DESCRIPTION OF THE PRIOR ART
[0001] Electrostatic copying apparatuses of various types have been suggested and come into
commercial acceptance in the past. In a typical electrostatic copying apparatus, a
rotating drum having a photosensitive member disposed on its peripheral surface is
provided, and around the rotating drum are located a charging zone, an exposure zone,
a developing zone, a transfer zone, a peeling zone and a cleaning zone in this order
in the rotating direction of the rotating drum. In the charging zone, the photosensitive
member is charged to a specified polarity by the action of a charging corona discharge
device, and in the exposure zone, the image of a document to be copied is projected
onto the photosensitive member, whereby the charge on the photosensitive member is
selectively eliminated and a latent electrostatic image is formed on the photosensitive
member. In the developing zone, a toner is applied to the latent electrostatic image
on the photosensitive member by, for example, a developing means of the magnetic brush
type to develop the latent electrostatic image into a toner image. In the transfer
zone, the toner image on the photosensitive member is transferred onto a copying paper
conveyed through the transfer zone. In the peeling zone, the copying paper contacted
with the photosensitive member in the transfer zone is peeled off from the photosensitive
member. In the cleaning zone, the toner remaining on the photosensitive member after
the transfer is removed by, for example, the action of a cleaning blade to be in contact
with the photosensitive member. In the meantime, the copying paper having the toner
image transferred thereto, which has been peeled from the photosensitive member in
the peeling zone, is passed through a fixing device such as a heat fixing device whereby
the toner image is fixed to the copying paper in the fixing device.
[0002] As is well known, the electrostatic copying apparatus described above frequently
has a semi-automatic document supplying and discharging device and a sorter annexed
thereto. The semi-automatic document supplying and discharging device feeds a document
inserted by hand into its document introducing section to a document supporting transparent
plate disposed on the upper surface of the housing of the main body of the electrostatic
copying apparatus. The sorter is actuated when multiple copies are to be formed from
each of a plurality of documents, and sorts the copying papers having a fixed toner
image which are discharged from the main body of the electrostatic copying apparatus.
[0003] The conventional electrostatic copying apparatus, however, has various inconveniences
or defects in regard to the following operations and devices which will be described
in detail hereinafter.
(1) Control of the positioning of the cleaning blade adapted to be selectively positioned
at its operating position at which it is brought into contact with the photosensitive
member and at its non-operating position at which it is moved away from the photosensitive
member, when the cleaning blade is used with the magnetic brush-type developing means;
(2) Control of continued delivery of copying papers in response to the copying process
performed continuously, when there is used a copying paper feed device loaded with
a copying paper cassette containing a plurality of stacked paper sheets;
(3) Displaying of the number of copying papers to be removed by hand (i.e., copying
papers present in and outside the paper conveying passage), when a trouble occurs
in the conveying of paper;
(4) Counting of the number of copying cycles when a trouble occurs in the transfer
of a document in a semi-automatic document supplying and discharging device annexed
to the electrostatic copying apparatus;
(5) Realization of interruption in the copying process when the semi-automatic document
supplying and discharging device is annexed to the electrostatic copying apparatus;
(6) Control based on the temperature of the surface or its vicinity of the photosensitive
member;
(7) Control of the energization or deenergization of an electric heating means when
a heat-fixing device containing the electronic heating means is used;
(8) Control of distributing an electric power when the heat-fixing device having the
electric heating means is used; and
(9) electrical detecting devices for temperature, etc.
[0004] In particular, conventional copying apparatuses have the following inconvenience.
If the apparatus is in a fault condition, the fault is steadily displayed. In addition
there are many other displays like selected original size, paper size, sorter, handler
etc. activated, hereby confusing an unskilled operator and embarassing him so that
he does not know which action is to be taken.
[0005] The general object of this invention is to remove this inconvenience.
[0006] An electrostatic copying apparatus in accordance with the invention is stated in
claim 1. Advantageous further embodiments of the invention are subject of the dependent
claims.
[0007] Various specific objects of this invention will become apparant from the following
detailed description of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008]
Figure 1 is a perspective view of one embodiment of the copying apparatus constructed
in accordance with this invention in a condition in which the a semi-automatic document
supplying and discharging device is held in its operating position;
Figure 2 is a perspective view of the copying apparatus of Figure 1 in a condition
in which the semi-automatic document supplying and discharging device is held in its
non-operating position;
Figure 3 is a simplified sectional view of the copying apparatus shown in Figure 1;
Figure 4 is a simplified partial sectional view showing a rotating drum and its vicinity
in the copying apparatus shown in Figure 1;
Figure 5 is a simplified partial sectional view showing a paper feed device in the
copying apparatus shown in Figure 1;
Figure 6 is a simplified partial view showing a panel in the copying apparatus shown
in Figure 1;
Figure 7 is a simplified block diagram showing processing means and various detecting
means for feeding signals thereto;
Figure 8 is a flow chart showing the manner of controlling cleaning in the copying
apparatus shown in Figure 1;
Figure 9 is a flow chart showing the manner of controlling the supply of a copying
paper in the copying apparatus shown in Figure 1;
Figures 10-A to 10-D are flow charts showing the manner of controlling trouble shooting
and display in the copying apparatus shown in Figure 1;
Figures 11-A to 11-D are simplified views showing examples of display means in the
copying apparatus shown in Figure 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0009] The invention will be described in detail with reference to the accompanying drawings.
General Outline of Copying Apparatus
[0010] The outline of the construction of one embodiment of an electrostatic copying apparatus
will be described.
[0011] With reference to Figures 1 and 2, the illustrated electrostatic copying apparatus
has a main body shown generally at 2 which includes a nearly rectangularly-shaped
housing 4. The copying apparatus further includes a semi-automatic document supplying
and discharging device shown generally at 6 and annexed to the upper surface of the
housing 4, a document holding mechanism shown generally at 8 and annexed similarly
to the upper surface of the housing 4, and a sorter shown generally at 10 and annexed
to one side surface of the housing 4.
[0012] The semi-automatic document supplying and discharging device 6 includes a stationary
support frame structure 14 mounted on the top of the housing 4 adjacent to one side
edge of the transparent plate 12 (Figure 3) disposed on the top of the housing 4,
and a movable main frame structure 16 mounted for free turning about an axis extending
along said one side edge of the transparent plate 12 and between an operating position
(the position shown in Figure 1) at which it covers the transparent plate 12 and a
non-operating position (the position shown in Figure 2 which is displaced about 90°
from the above operating position in a clockwise direction as viewed from the right
bottom in Figures 1 and 2) at which it brings the transparent plate 12 to view. On
the other hand, the document holding device 8 is mounted such that it is free to turn
between an operating position at which it covers the transparent plate 12 (the position
shown in Figure 2) and a non-operating position (the position shown in Figure 1 displaced
about 90° from the above operating position as viewed from the right top in Figures
1 and 2) at which it brings the transparent plate 12 to view, and about an axis extending
along the other side edge of the transparent plate 12 which extends substantially
at right angles to the pivot axis of the main frame structure 16 of the semi-automatic
document supplying and discharging device 6. In positioning a document to be copied
on the transparent plate 12 by utilizing the semi-automatic document supplying and
discharging device 6 in the above-illustrated electrostatic copying apparatus, the
document holding device 8 is brought to the non-operating position and the main frame
structure 16 of the semi-automatic document supplying and discharging device 6 is
brought to the operating position. When the document to be copied is to be positioned
on the transparent plate 12 by a manual operation without utilizing the semi-automatic
device 6 (for example, when the document is a thick one such as a book or one having
relatively high rigidity, such as a thick sheet of paper or a metal plate), the operator
brings the main frame structure 16 of the semi-automatic device 6 to the non-operating
position, then places the document on the desired site of the transparent plate 12,
turns the document holding device 8 to the above operating position, and thus covers
the transparent plate 12 and the document thereon with the document holding device
8. In withdrawing the document after the end of a copying cycle, the document holding
device 8 is turned to the non-operating position.
[0013] With reference to Figure 3, the main body 2 of the copying apparatus will be described.
The transparent plate 12 on which to place a document to be copied is disposed on
the upper surface of the housing 4. A cylindrical rotating drum 18 is rotatably mounted
substantially centrally at the lower part of the housing 4, and an endless photosensitive
member 20 is provided on the peripheral surface of the rotating drum 18. It is also
possible to use an endless belt element known to those skilled in the art in place
of the rotating drum 18 and to dispose the photosensitive member on the surface of
the endless belt element. With reference to Figure 4 together with Figure 3, around
the rotating drum to be rotated in the direction of an arrow 22 are located a charging
zone 24, an exposure zone 26, a developing zone 28, a transfer zone 30, a peeling
zone 32 and a cleaning zone 34 in this sequence as viewed in the rotating direction
of the rotating drum 18. The charging zone 24 and the exposure zone 26, taken together,
form a latent electrostatic image-forming zone 36. A charging corona discharge device
38 is disposed in the charging zone 24, and a developing means 40 of the magnetic
brush type in any desired form is disposed in the developing zone 28. A transfer corona
discharge device 42 is disposed in the transfer zone 30, and peeling corona discharge
devices 44 and 46 are disposed in the peeling zone 32. In the cleaning zone 34, a
cleaning blade 48 is provided.
[0014] A paper conveying means shown generally at 50 is provided in the lower portion of
the housing 4. A paper feed device 52 is disposed at the upstream end portion (the
right end portion in Figure 3) of the paper conveying means 50. With reference to
Figure 5 taken in conjunction with Figure 3, the paper feed device 52 includes a first
cassette-receiving section 54a and a second cassette-receiving section 54b located
above it. The first cassette-receiving section 54a receives a paper cassette 58a containing
a plurality of stacked copying paper sheets 56a, and the second cassette-receiving
section 54b receives a paper cassette 58b containing a plurality of stacked copying
paper sheets 56b. A first paper supply means 60a and a second paper supply means 60b
are provided respectively in the first cassette-receiving section 54a and the second
cassette-receiving section 54b. The first paper supply means 60a is comprised of a
support shaft 62a and a supply roller 64a fixed thereto, and the second paper supply
means 60b is comprised of a support shaft 62b and a supply roller 64b fixed thereto.
To the first cassette-receiving section 54a is annexed a first paper introducing passage
70a defined by a pair of guide plates 66 and 68. Likewise, a second paper introducing
passage 70b defined by a pair of guide plates 72 and 74 and a pair of guide plates
76 and 78 is annexed to the second cassette-receiving section 54b. A pair of supply
assisting rollers 80 and 82 are provided between the pair of guide plates 72 and 74
and the pair of guide plates 76 and 78. Further, with reference to Figure 3, a pair
of conveyor rollers 84 and 86 are provided at a point of junction of the first paper
introducing passage 70a and the second paper introducing passage 70b, and following
this pair of conveyor rollers 84 and 86, a pair of guide plates 88 and 90, a pair
of conveyor rollers 92 and 94 and a pair of guide plates 96 and 98 are provided. The
downstream end of the pair of guide plates 96 and 98 extend to the upstream end of
the transfer zone 30. A conveyor belt mechanism 100 is disposed downstream of the
peeling zone 32 as viewed in the paper conveying direction. A guide plate 102 is disposed
downstream of the conveyor belt mechanism 100, and a heat-fixing device 104 is disposed
downstream of the guide plate 102. The heat-fixing device 104 is comprised of a heating
roller 108 having an electrical heating means 106 therein, and a press-contact roller
110 cooperating with the heating roller 108. A pair of guide plates 112 and 114 are
disposed downstream of the heat-fixing device 104. In the paper conveying means 50
of the aforesaid construction, a copying paper is supplied through the first paper
introducing passage 70a from the paper cassette 58a in the paper feed device 52 or
through the second paper introducing passage 70b from the paper cassette 58b (the
paper feed device 52 will be described in more detail hereinafter), and conveyed to
the transfer zone 30 by the pair of conveyor rollers 84 and 86, the pair of guide
plates 88 and 90, the pair of conveyor rollers 92 and 94, and the pair of guide plates
96 and 98. The paper is brought into contact with the photosensitive member 20 on
the rotating drum 18 in the transfer zone 30, then peeled from the photosensitive
member 20 in the peeling zone 32, thereafter conveyed by the conveyor belt mechanism
100, introduced into the heat-fixing device 104
via the guide plate 102, and thereafter passed through the pair of guide plates 112 and
114 and discharged into the sorter 10.
[0015] In the upper portion of the housing 4, there is provided an optical unit generally
shown at 116 for scanning and exposing a document on the transparent plate 8 and projecting
its image onto the photosensitive member 20 on the rotating drum 18 in the exposure
zone 26. The optical unit 116 has a document illuminating lamp 118 for illuminating
the document placed on the transparent plate 8, a first reflecting mirror 120 for
projecting the reflected light from the document onto the photosensitive member 20,
a second reflecting mirror 122, a third reflecting mirror 124, a lens assembly 126
and a fourth reflecting mirror 128. During scanning and exposure, the document illuminating
lamp 118 and the first reflecting mirror 120 which are mounted on a common sup port
frame 130 are moved substantially horizontally at a predetermined speed V from their
initial position shown by the solid line to required positions (for example, maximum
scanning-exposure termination positions shown by the two-dot chain line), and the
second reflecting mirror 122 and the third reflecting mirror 124 which are mounted
on a common support frame 132 are moved at a speed one half of the aforesaid speed
(i.e., ½V) from their initial positions shown by the solid line to required positions
(for example, maximum scanning-exposure termination positions shown by the two-dot
chain line). At this time, the light reflected from the document illuminated by the
document illuminating lamp 118 is reflected successively by the first reflecting mirror
120, the second reflecting mirror 122 and the third reflecting mirror 124 and reaches
the lens assembly 126. Thereafter, it is reflected by the fourth reflecting mirror
126 and reaches the photosensitive member 20 in the exposure zone 26. When the scanning
exposure is terminated, the document illuminating lamp 118, the first relfecting mirror
120, the second reflecting mirror 122 and the third reflecting mirror 124 are returned
to their initial positions shown by the solid line.
[0016] In the main body 2 of the copying apparatus described above, while the rotating drum
is rotated in the direction of arrow 22, the charging corona discharge device 38 substantially
uniformly charges the photosensitive member 20 to a specified polarity in the charging
zone 24, and thereafter in the exposure zone 26, the optical unit 116 projects the
image of the document to eliminate the cahrge on the photosensitive member 20 selectively,
whereby a latent electrostatic image corresponding to the document is formed on the
photosensitive member 20. Thereafter, the developing means 40 applies a toner to the
latent electrostatic image on the photosensitive member 20 to develop the latent electrostatic
image to a toner image. Then, in the transfer zone 30, a copying paper conveyed by
the paper conveying means 50 is brought into contact with the photosensitive member
20, and by the action of the transfer corona discharge device 42, the toner image
on the photsensitive member 20 is transferred to the paper. Subsequently, in the peeling
zone 32, the copying paper is peeled from the photosensitive member 20 by the action
of the peeling corona discharge devices 44 and 46. The copying paper having the toner
image transferred thereto is then conveyed to the heat-fixing device 104 where the
toner image is fixed to the copying paper. The paper is then discharged into the sorter
10. In the meantime, the photosensitive member 20 continues to rotate, and the toner
remaining on the photosensitive member 20 after the transfer operation is removed
from it by the action of the cleaning blade 48 in the cleaning zone 34 or by the action
of the magnetic brush-type developing means 40 in the developing zone 28.
[0017] With reference to Figure 3, the semi-automatic document supplying and discharging
device 6 will be generally described. The semi-automatic device 6 includes the stationary
support frame structure 14 and the movable main frame structure 16, as already stated
above. As can be seen from Figure 3, the support frame structure 14 is mounted on
one end portion (the right end portion in Figure 3) of the top of the housing 4 adjacent
to one side edge of the transparent plate 12 fixed to the top of the housing 4. A
shaft 130 extending in the front and rear direction (a direction perpendicular to
the sheet surface in Figure 3) is rotatably mounted on the support frame structure
10. One end portion (the right end portion in Figure 3) of the main frame structure
16 is mounted pivotally on the shaft 130. The main frame structure 16 has an upper
plate 132 and a lower plate 134. The upper plate 132 defines a substantially flat,
document receiving surface 136 on the top side of the main frame structure 16. As
will be described below, the document receiving surface 136 receives the document
discharged from the main frame structure 16. Preferably, a restraining member 138
for restraining the leading edge of the document discharged onto the receiving surface
136 to put it in order is secured to the top side of the upper plate 132 in such a
manner that its position can be adjusted according to the size of the document. When
the main frame structure 16 is held at the operating position as shown in Figure 3,
the lower plate 134 defining the under side of the main frame 16 is positioned slightly
upwardly of, and substantially parallel to, the transparent plate 12 to define a main
portion 142 of a document conveying passage 140 between it and the top side of the
transparent plate 12. The document conveying passage 140 additionally has an introducing
portion 144 located upstream of the main portion 142 and a curved discharging portion
146 connecting the main portion 142 to the document receiving surface 136. The introducing
portion 144 is defined in the support frame structure 14, and the curved discharging
portion 146 is defined in the other end portion, i.e. the free end portion (the left
end portion in Figure 3) of the main frame structure 16. The introducing portion 144
of the document conveying passage 140 is defined between a lower guide plate 148 and
two upper guide plates 150 and 152. A document stand 154 is annexed to the upstream
side of the support frame structure 14. The surface of the document stand 154 defines
a guide surface 156 for manually positioning a document to be copied, which joins
the upstream end of the introducing portion 144 of the document conveying passage
140. On the surface of the document stand 154 is formed a guiding protrusion 158 which
restrains the position of one side edge of a document placed on the guide surface
156 for insertion into the introducing portion 144 of the conveying passage 140 and
thus restricts the position of the document in the widthwise direction. In the introducing
portion 144 of the document conveying passage 140, there are further provided a conveying
roller unit 160 for conveying the document inserted into the introducing portion 144
to the main portion 142 through the introducing portion 144 and a first regulating
member 162 for regulating the position of the document, which projects into the introducing
portion 144 at a position downstream of the conveying roller unit 160 and can arrest
the advancing of the document passing through the introducing portion 144. The conveying
roller unit 160 is comprised of a driven roller 164 and a follower roller 166. A solenoid
168 is provided in relation to the conveying roller unit 160 and the first regulating
member 162. When the solenoid 168 is in the deenergized state, the follower roller
166 is positioned below the lower guide plate 148 away from the driven roller 164,
and the first regulating member 162 projects into the introducing portion 144 through
an opening formed in the lower guide plate 148 to hamper the advancing of the document.
On the other hand, when the solenoid is energized, the follower roller 166 projects
into the introducing portion through the opening formed in the lower guide plate 148
and is pressed against the driver roller 164, and the first regulating member 162
moves away from the introducing portion 144 and is located below the lower guide plate
148 to permit the advancing of the document.
[0018] The semi-automatic document supplying and discharging device 6 further includes a
conveyor belt mechanism 170 for conveying the document, which has been sent to the
main portion 142 of the conveying passage 140 from the introducing portion 144, through
the main portion 142, further conveying it from there through the curved discharging
portion 146 and discharging it onto the document receiving surface 136. The conveyor
belt mechanism 170 has a plurality of laterally spaced endless belts 172 (only one
of which is shown on Figure 3) which are wrapped about a driven wheel 174 mounted
on the shaft 130 and follower wheels 180 and 182 mounted respectively on shafts 176
and 178 mounted on the free end portion (the left end portion in Figure 3) of the
main frame structure 16. A tension roller 184 and a tension rod 186 for maintaining
the endless belts 172 taut are also provided. The lower travelling section of the
endless belts 172 extends between the lower plate 134 and the transparent plate 12.
The shaft 130 on which the driven wheel 174 is mounted is drivingly connected to an
electric motor 188 mounted on the support frame structure 14, and rotated clockwise
in Figure 3 when the motor 188 is energized. In the intermediate portion of the main
portion 142 of the conveying passage 140 is provided a hemispherical pressing piece
190 projecting downwardly through an opening formed in the lower plate 134 for forcing
the endless belts 172 downwardly. The second regulating member 192 and a rotatably
mounted pressing roller 194 are provided in the downstream end portion of the main
portion 142. A solenoid 196 is provided in relation to the second regulating member
192 and the pressing roller 194. When the solenoid 196 is in the deenergized state,
the second regulating member 192 projects into the main portion 142 of the conveying
passage 140 through the opening formed in the lower plate 134 to hamper the advancing
of the document, and the pressing roller 194 is located above the lower plate 134.
On the other hand, when the solenoid 196 is energized, the second regulating member
192 moves away from the main portion 142 and is located above the lower plate 134,
while the pressing roller 194 projects downwardly through the opening formed in the
lower plate 134 to force the endless belts 172 downwardly. In the curved discharging
portion 146 of the conveying passage 140, a roller 198 located opposite to the wheel
180 and a roller 200 located opposite to the wheel 182 are rotatably mounted. The
rollers 198 and 200 cooperate with the endless belts 172.
[0019] Since the semi-automatic document supplying and discharging device 6 described above
is substantially the same as the semi-automatic document supplying and discharging
device disclosed in Japanese Laid-Open Patent Publication No. 161874/1982 (corresponding
to U. S. Patent Application Serial No. 361,236 and European Patent Application No.
82102455.1), the disclosure of the aforesaid Japanese Laid-Open Patent Publication
No. 161874/1982 is cited herein as reference in lieu of a detailed description of
the device 6.
[0020] The sorter 10 has a frame structure 202 having an open front side. The inside of
the frame structure 202 includes a plurality of vertically stacked bins 204 and a
moving means 206 for suitably moving the bins 204. When the copying process is to
be repeated a number of times for the same document, after a copy (i.e., a copying
paper having a fixed toner image) formed in a given copying cycle is received in the
lowermost bin 204, the moving means 206 immediately moves downwardly that bin 204
which exists immediately above the aforesaid bin so as to receive a copy to be formed
in the next copying cycle. After a copy in the final cycle of the copying process
is received in a specified bin 204, the moving means 206 raises those bins 204 excepting
the lowermost bin 204 to return them to the initial positions shown in Figure 3. The
sorter 10 itself may be substantially the same as the sorter disclosed in the specification
of Japanese Patent Application No. 162205/1981, and a detailed description of the
structure of the sorter 10 itself is omitted in this specification.
Detecting means, manually operable switches, display means, etc.
[0021] With reference to Figures 3 and 5, in the paper feed device 52 in the main body 2
of the electrostatic copying apparatus either one of three types of paper cassettes
containing copying paper sheets according to JIS standards A3, A4 and A5 is mounted
on the first cassette-receiving section 54a, and either one of three types of paper
cassettes containing paper sheets according to JIS standards B4, B5, and B6 is mounted
on the second cassettereceiving section 54b. In the first cassette-receiving section
54a and the second cassette-receiving section 54b, discriminating means 208a and 208b
are respectively provided for determining which of the three types of paper cassettes
has been mounted. Each of the discriminating means 208a and 208b may be comprised
of two reed switches disposed in spaced-apart relationship in the widthwise direction.
In this case, two permanent magnets (not shown) are fixed to the opposite sides of
the front surface of each of the A3 paper cassette containing paper sheets having
a size A3 and the B4 paper cassette containing paper sheets having a size B4, for
example; one permanent magnet is fixed to one side of the front surface of each of
the A4 paper cassettes containing paper sheets having a size A4 and the B5 paper cassette
containing paper sheets having a size B5; and one permanent magnet is fixed to one
side of the front surface of each of the A5 paper cassette containing paper sheets
having a size A5 and the B6 paper cassette containing paper sheets having a size B6
which side is opposite to said one side of the front surface of the A4 or B5 paper
cassette. Accordingly, when the A3 paper cassette is to be loaded on the first cassette-receiving
section 54a, both of the two reed switches consitituting the discriminating means
208a are closed. When the A4 paper cassette is to be loaded therein, one of the two
reed switches is closed. Furthermore, when the A5 paper cassette is to be loaded,
the other of the two reed switches is closed. Likewise, when the B4 paper cassette
is to be loaded in the second cassette-receiving section 54b, both of the two reed
switches constituting the discriminating means 208b are closed. When the B5 paper
cassette is to be loaded, one of the two reed switches is closed. Furthermore, when
the B6 paper cassette is to be loaded, the other of the two reed switches is closed.
[0022] Detecting means 210a and 210b for detecting the rotation or stopping of the shafts
62a and 62b are provided with respect to each of the shaft 62a fixed to the supply
roller 64a and the shaft 62b fixed to the supply roller 64b in the paper feed device
52. The detecting means 210a and 210b are comprised respectively of discs 212a and
212b fixed on one end portions of the shafts 62a and 62b and stationary photocouplers
214a and 214b consisting of light emitting elements located on one side of the discs
212a and 212b and light-receiving elements located on the other sides of the discs
212a and 212b. A number of cuts are formed at suitable intervals in the circumferential
direction in the circumferential edge portion of each of the discs 212a and 212b.
When each of the shafts 62a and 62b is at rest, a cut or a portion between cuts of
each of the discs 212a and 212b exists continuously between the light-emitting element
and the light-receiving element of each of the photocouplers 214a and 214b, and therefore
the light-receiving element of each of the photocouplers 214a and 214b is continuously
maintained in condition for receiving light from the light-emitting element or for
not receiving it. On the other hand, when each of the shafts 62a and 62b is rotated,
a cut and a portion between cuts of each of the discs 212a and 212b alternately pass
between the light-emitting element and the light receiving element of each of the
photocouplers 214a and 214b, and therefore, the light receiving element of each of
the photocouplers 214a and 214b is alternately maintained in condition for not receiving
light from the light emitting element and for receiving it.
[0023] As clearly shown in Figure 5, a paper detecting means 216 is provided in relation
to both of the first paper introducing passage 70a extending from the first cassette-receiving
section 58a and the second paper introducing passage 70b extending from the second
cassette-receiving section 58b. The detecting means 216 includes a microswitch 220
having an actuating arm 218, a detecting piece 224a mounted pivotally on a shaft 222a
and projecting into the first paper introducing passage 70a through an opening formed
in the guide plate 66, and a detecting piece 224b mounted pivotally on a shaft 222b
and projecting into the second paper introducing passage 70b through an opening formed
in the guide plate 76. When the leading edge of the copying paper 56a supplied to
the first paper introducing pasage 70a from the cassette 58a by the action of the
supply roller 64a rotated in the direction of the arrow comes into contact with the
nip position of the pair of conveyor rollers 84 and 86 and consequently the copying
paper 56a is bent as shown by the two-dot chain line, the detecting piece 224a is
caused to pivot counterclockwise from its normal position shown in the drawing, and
as a result, a projection 226 of the detecting piece 224a acts on the actuating arm
218 of the microswitch 220 to close the microswitch 220. When the leading edge of
the copying paper 56b supplied to the second paper introducing passage 70b from the
paper cassette 58b by the action of the supply roller 64b rotated in the direction
of the arrow and conveyed through the second paper introducing passage 70b by the
action of the pair of supply assisting rollers 80 and 82 rotated in the direction
of the arrow comes into contact with the nip position of the pair of conveyor rollers
84 and 86 and as a result, the copying paper 56b is bent as shown by the two-dot chain
line, the detecting piece 224b is caused to pivot clockwise from its normal position
shows in the drawing. As a result, a projection 228b of the detecting piece 224b acts
on the projection 228a of the detecting piece 224a to cause the detecting piece 224a
to pivot counterclockwise from its normal position shown in the drawings. Finally,
the projection 226 of the detecting piece 224a acts on the actuating arm 218 of the
microswitch 220 to close the microseitch 220. A copying paper detecting means 228
is further provided with regard to the second paper introducing passage 70b. The detecting
means 228 is constructed of a microswitch having an actuating arm 230 which projects
into the second paper introducing passage 70b through the opening formed in the guide
plate 74 upstream of the pair of supply assisting rollers 80 and 82. When the leading
edge of the copying paper 56b supplied to the second paper introducing passage 70b
from the copying paper cassette 58b acts on the actuating arm 230, the detecting means
228 is closed, and when the trailing edge of the paper 56b goes past the actuating
arm 230, the detecting means 228 is opened.
[0024] Again with reference to Figure 3, the main body 2 of the electrostatic copying apparatus
further includes paper detecting means 232, 234 and 236 which detect a copying paper
conveyed by the paper conveying means 50, at a position slightly downstream of the
pair of conveyor rollers 84 and 86, at a position slightly downstream of the peeling
zone and at a position slightly downstream of the heat-fixing device 104 (the downstream
end portion of the paper conveying passage in the main body 2). The detecting means
232, 234 and 236 respectively have actuating arms 238, 240 and 242 projecting into
the paper conveying passage, and are closed when the leading edge of the copying paper
acts on the actuating arms 238, 240 and 242 respectively and are opened when the trailing
edge of the copying paper goes past the actuating arms 238, 240 and 242.
[0025] With reference to Figures 3 and 4, there is provided a paper wrapping detecting means
244 which when a copying paper kept in contact with the photosensitive member 20 on
the rotating drum 18 in the transfer zone 30 wraps about the photosensitive member
20 without being peeled from the photosensitive member 20 in the peeling zone, detects
the wrapping paper. The detecting means 244 is comprised of a light emitting element
246 for irradiating light onto the photosensitive member 20 at a position slightly
downstream of the peeling zone as viewed in the rotating direction of the rotating
drum 18, a light receiving element for receiving the light reflected from the photosensitive
member 20, and a signal generator 250 electrically connected to the light receiving
element 248 for producing a paper wrapping signal when the intensity of light received
by the light receiving element is below a predetermined threshold value. The photosensitive
member 20 itself has a high reflectance, and therefore when the paper is not wrapped
about the photosensitive member 20, the light receiving element 248 receives light
having a sufficient intensity. However, when the paper wraps about the photosensitive
member, the light receiving element 248 receives light having an intensity below the
threshold value and the signal generator 250 produces a paper wrapping signal, because
the copying paper has a relatively low reflectance. Preferably, the distance ℓ₂ from
the peeling zone 32 to the detecting position of the detecting means 244 as viewed
in the rotating direction of the rotating drum 18 is substantially equal to the distance
ℓ₁ from the peeling zone 32 to the detecting position of the detecting means as viewed
in the moving direction of the copying paper.
[0026] With reference to Figure 3, the main body 2 of the electrostatic copying apparatus
further has disposed therein detecting means 252 and 254 for detecting the support
frame 132 on which the second reflecting mirror 122 and the third reflecting mirror
124 in the optical unit 116 are mounted. Each of the detecting means 252 and 254 may
be constructed of a reed switch to be actuated by a permanent magnet fixed to the
support frame 132. The detecting means 252 detects the support frame 132 when the
support frame 132 is at its initial position shown by the solid line. The detecting
means 254 detects the support frame 132 and is closed, when the support frame 132
moves from its initial position to a position displaced to the right by a predetermined
distance ℓ₃.
[0027] A detecting means 256 which may be of any known form is disposed in the sorter 10,
which when a trouble occurs (for example, when the bins 204 are not moved as required),
detects it and produces a signal.
[0028] In the semi-automatic document supplying and discharging device 6, there is provided
a document insertion detecting means 258 which detects a document at that position
of the introducing portion 144 of the conveying passage 140 which is slightly upstream
of the document advancing arresting position of the first regulating member 162. The
detecting means 258 may be comprised of a light emitting element 260 located above
the introducing portion 144 and a light receiving element 262 located below the introducing
portion 144. When a document is inserted by hand into the introducing portion 144,
light projected onto the light receiving element 262 from the light emitting element
260 is shut off by the document, whereupon the detecting means 258 produces a document
insertion signal. There is also provided a detecting means 264 which detects a document
at that position of the main portion 142 of the conveying passage 140 which is slightly
upsteam of the document advancing arresting position of the second regulating member
192. The detecting means 264 may be constructed of a light emitting element for projecting
light onto the transparent plate 12, a light receiving element for receiving light
reflected from the transparent plate 12, and a signal generator which produces a document
detection signal when the intensity of the light received by the light receiving element
falls below a predetermined threshold value. Since the transparent plate 12 itself
has a high reflectance, the light receiving element receives light of a sufficient
intensity when no document exists at the detecting position. On the other hand, because
the reflectance of the document is relatively low, when the leading edge of the document
arrives at the detecting position, the light receiving element receives light having
an intensity below the predetermined threshold value, and the signal generator produces
a document detection signal. When the trailing edge of the document goes past the
detecting position, the light receiving ele- ment again receives light having a sufficient
intensity and the above document detection signal disappears. Furthermore, a detecting
means 266 is provided which detects the document at the downstream end portion of
the curved discharging portion 146 of the conveying passage 140. The detecting means
266 is comprised of a microswitch 270 having an actuating arm 268, and a detecting
piece 272 mounted pivotally by a supporting pin 271. One end portion of the detecting
piece 272 projects into the curved discharging portion 146. When the leading edge
of the document acts on one end portion of the detecting piece 272, the detecting
piece 272 is caused to pivot counterclockwise from its normal position shown in the
drawing. As a result, the other end portion of the detecting piece 272 acts on the
actuating arm 268 of the microswitch 270 to close the microswitch 270. When the trailing
edge of the document goes past the one end portion of the detecting piece 272, the
detecting piece 272 returns to its normal position shown in the drawings, and the
microswitch 270 is opened.
[0029] In the illustrated copying apparatus, there are further provided known suitable detecting
means (inclusively designated by numeral 275) which detect a disorder in various other
constituent elements such as the document illuminating lamp 118 (Figure 3), the electrical
heating means 106 (Figure 3) in the heat-fixing means, and the electrical heating
means 273 (Figure 4) for heating the photosensitive member 20. The electrical heating
means 273 (Figure 4) for heating the photosensitive member 20 will be described further
hereinafter. In the illustrated copying apparatus, a temperature detecting means 277
(Figure 3) for detecting the temperature of the heat-fixing device 104 and a temperature
detecting means 279 (Figure 4) for detecting the temperature of the surface or its
vicinity of the photosensitive member 20 are further provided. Detecting devices 281
and 283 respectively including the temperature detecting means 277 and 279 produce
not only a temperature signal but also a signal showing a disorder which occurs in
the temperature detecting means 277 and 279, as will be described in detail hereinbelow.
[0030] With reference to Figures 1 and 2, a key card inserting section 274 is provided at
the front end portion of the upper surface of the housing 4 of the main body 2 of
the copying apparatus. A given key card 276 is inserted into the key card inserting
section by an operator. In the key card inserting section 274 is provided a signal
producing means 278 which when the key card 276 is inserted, detects it and produces
a copying process performance permission signal (Figure 7). As will be described hereinafter,
in the illustrated electrostatic copying machine, the copying process cannot be performed
unless the operator inserts the key card 276 into the key card inserting section 274
thereby producing the aforesaid signal for the permission of the performance of the
copying process, as will be described in more detail hereinafter. This prevents any
unauthorized person from operating the copying apparatus and obtaining copies. Adjacent
to the key card inserting section 274, a panel 280 is disposed at the front end portion
of the upper surface of the housing 4. Referring to Figure 6, the panel 280 has arranged
thereon a power switch 282, a print switch 284, a paper selection switch 286 and an
interruption switch 288. When the power switch 282 is closed by a manual operation,
the copying apparatus is connected to a suitable power supply such as a commercial
alternate-current power supply, and when the power switch 282 is opened, the copying
apparatus is cut off from the power supply. When the print switch 284 is instantaneously
closed by a manual operation, a signal for starting the copying process is produced.
The paper selection switch 286 is maintained in one of two conditions. When it is
maintained in one condition, the supply roller 64a in the paper feed device 52 is
set in an operable condition (therefore, a copying paper is ready for supplying from
the paper cassette 58a loaded in the first cassette-receiving section 54a). When it
is maintained in the other condition, the supply roller 64b in the paper feed device
52 is set in an operable condition (therefore, a copying paper is ready for supplying
from the paper cassette 58b loaded in the second cassette receiving section 54b) (Figures
3 and 5). The interruption switch 288 is manually closed when so-called "interrupting
copying" is to be performed, as will be described hereinafter. An operating knob 289
for controlling the amount of light exposure on the photosensitive member 20 is also
disposed on the panel 280. The panel 280 further includes ten input keys from 0 to
9 for inputting the number of copies to be produced from each document and a clear
key 292 for cleaning the input numeral set by these input keys 290. The panel 280
further has a key card lamp 294 for showing that the key card 276 has not been inserted
into the key card inserting section 274 and the copying process performance permission
signal has not yet been produced; a waiting display lamp 296 for showing that the
heat-fixing device 104 has not yet attained the required temperature; a service man
call lamp 298 showing that a disorder has occured in a constituent element in the
copying apparatus and a service man is required for inspection and repair; and a trouble
lamp 300 which shows that a trouble has occured in the conveying of a copying paper
in the main body 2 of the copying apparatus, a trouble has occured in the conveying
of a document in the semi-automatic document supplying and discharging device, or
a trouble has occurred in the sorter 10. A first display means 302 and a second display
means 304 are also arranged on the panel 280. Each of the first display means 302
and the second display means 304 has two light emitting segments having the shape
of the arabic figure 8. The mode of display by the first and second display means
302 and 304 will be described in more detail hereinafter.
Basic operating procedure of the copying apparatus
[0031] The operations of the copying apparatus as described hereinabove is controlled by
a processing means 306 including microprocessors constituting various control and
discriminating means.
[0032] With reference to Figures 3 and 7, when the power switch 282 (Figure 6) is manually
closed, power is applied to the copying apparatus, whereby a waiting flag 308 included
in the processing means 306 is set at logic "1" and the electrical heating means 106
of the heat fixing device 104 and the electrical heating means 273 (Figure 4) for
heating the photosensitive member 20 are energized (the controlling of the energization
and deenergization of the heating means 106 and the heating means 273 will be described
in more detail hereinafter). When the waiting flag 308 is set at logic "1", the waiting
display lamp 296 (Figure 6) is energized to indicate that the copying apparatus is
in a preparatory condition, and the copying apparatus is prevented from performing
the copying process described below. When the temperature of the heat fixing device
104 detected by the temperature detecting means 277 exceeds a predetermined value
as a result of heating by the heating means 106, the waiting flag 308 is reset at
logic "0", and the waiting display lamp (Figure 6) is deenergized.
[0033] The operator manipulates ten input keys 290 to input the number of copies to be produced
from the same document. As a result, a copy number setting counter 310 included in
the processing means 306 is set at a predetermined number, whereby a continuity flag
312 included in the processing means 306 is set at logic "1". The logic "1" of the
continuity flag 312 shows that the copying process should be continuously performed.
When the number of copies to be produced from the same document is only one, it is
not necessary to operate the input keys 290. In this case, the continuity flag 312
is set at logic "1" when the operator instantaneously closes the print switch 284
(Figure 6).
[0034] When the semi-automatic document supplying and discharging device 6 is not utilized,
a document is placed by hand on the transparent plate 12, and the document holding
device 8 is brought to its operating position (the position shown in Figure 2). Then,
the operator instantaneously closes the print switch 284 (Figure 6) by a manual operation,
whereupon a copying process performance signal is produced. If at this time, an inhibition
flag 314 included in the processing means 306 is not set at logic "1" (the setting
of the inhibiting flag 314 will be described hereinafter) and therefore the copying
process can be performed, the rotation of the rotating drum 18 and the operation of
the developing means 40 are started in response to the copying process performance
signal, and a copying paper is delivered from one of the paper cassettes 58a and 58b
in the paper feed device 52 (from which of the cassette 58a or 58b the paper is delivered
depends upon the condition of the paper selection switch 286 described hereinabove).
When the paper 56a is delivered from the paper cassette 58a, the supply roller 64a
is rotated. When the leading edge of the copying paper 56a delivered by the supply
roller 64a abuts against the nip position of the pair of stationary conveyor rollers
84 and 86 and the copying paper 56a is bent as shown by the two-dot chain line in
Figure 5, the detecting means 216 is closed to thereby stop the rotation of the supply
roller 64a. When the copying paper 56b is delivered from the paper cassette 58b, the
pair of supply assisting rollers 80 and 82 are rotated together with the supply roller
64b. When the leading edge of the copying paper 56b delivered by the supply roller
64b is detected by the detecting means 228, a first counter 316 for paper conveyance
included in the processing means 306 starts to count clock pulses supplied from a
clock pulse supply soruce 318. When the counter 316 has counted a predetermined number,
the rotation of the supply roller 64b is stopped, and the delivered copying paper
56b is fed by the pair of supply assisting rollers 80 and 82. The aforesaid predetermined
number counted by the counter 316 is set at a value corresponding to the time sufficient
for the leading edge of the copying paper 56b to reach the nip position of the pair
of supply assisting rollers 80 and 82. When the leading edge of the copying paper
56b fed by the pair of supply assisting rollers 80 and 82 abuts against the nip position
of the pair of stationary conveyor rollers 84 and 86 and the copying paper 56b is
bent as shown by the two-dot chain line in Figure 5, the detecting means 216 is closed
to thereby stop the rotation of the pair of supply assisting rollers 80 and 82.
[0035] When the above-described paper supplying action is terminated and the detecting means
216 is closed, the counted numbers of a copying cycle counter 320 and a copying paper
counter 322 included in the processing means 306 are increased by one. When the countered
number of the copying cycle counter 320 becomes equal to that of the copy number setting
counter 310, the continuity flag 312 is reset at logic "0". The paper counter 322
will be described further hereinafter.
[0036] At the same time, when the copying process performance signal is produced, the document
illuminating lamp 118 is energized, and a timing counter 324 included in the processing
means 306 starts to count clock pulses supplied from the clock pulse supply source
318. When the counter 324 has counted a first predetermined number, the supporting
frames 130 and 132 of the optical unit 116 begin to move to the right in Figure 3
from their initial positions shown by the solid line in Figure 3. Thereafter, when
the counter 324 has counted a second predetermined number, the charging corona discharge
device 38 is energized. Thus, a latent electrostatic image is formed on the photosensitive
member 20, and then developed into a toner image.
[0037] When the support frame 132 of the optical unit 116 has moved a predetermined distance
ℓ₃, the detecting means 254 detects it. As a result, the pair of conveyor rollers
84 and 86 (and the pair of supply assisting rollers 80 and 82) are rotated, and at
the same time, the pair of conveyor rollers 92 and 94, the conveying belt mechanism
100 and the rollers 108 and 110 of the heat-fixing device 104 are rotated. Thus, the
conveying of the copying paper having its leading edge located at the nip position
of the pair of conveyor rollers 84 and 86 is started.
[0038] When the detecting means 232 has detected the leading edge of the copying paper,
a first counter 326 for transfer included in the processing means begins to count
clock pulses supplied from the clock pulse supply source 318. When the counter 362
has counted a predetermined number, the transfer corona discharge device 42 is energized.
Thus, the toner image on the photosensitive member 20 is transferred to the copying
paper in the transfer zone. Thereafter, in the peeling zone 32, the copying paper
is peeled off from the photosensitive member 20 by the action of the peeling corona
discharge devices 44 and 46. By the copying process performance signal, the peeling
corona discharge devices 44 and 46 begin to be energized as soon as the rotating drum
18 begins to rotate, and are deenergized when the rotation of the rotating drum 18
is stopped after the termination of the copying process.
[0039] When the copying paper is further conveyed, and the detecting means 232 detects the
passage of the trailing edge of the copying paper past the de- tecting position of
the detecting means 232, the charging corona discharge device 38 and the document
illuminating lamp 18 are deenerigized, and furthermore, the supporting frames 130
and 132 of the optical unit 116 stop moving to the right in Figure 3 and begin to
move to the left in Figure 3. At the same time, a second counter 328 for transfer
included in the processing means 306 begins to count clock pulses supplied from the
clock pulse supply source 318. When the counter 328 has counted a predetermined number,
the transfer corona discharge device 42 is deenergized.
[0040] The copying paper is further conveyed by the conveying belt mechanism 100 and the
rollers 108 and 110 of the heat fixing device 104, and discharged into the sorter
10. When at this time, the continuity flag 312 is set at logic "1", one bin 204 of
the sorter 10 is moved downwardly when a second paper conveyance counter 330, which
begins to count clock pulses supplied from the clock pulse supply source 318 when
the trailing edge of the copying paper has gone past the deetecting position of the
detecting means 236, has counted a predetermined number. Simultaneously, the counted
number of the paper counter 322 is decreased by one.
[0041] When the support frames 130 and 132 of the optical unit 116 moving to the left in
Figure 3 reach their initial positions shown by the solid line in Figure 3, the detecting
means 252 detects it. When the continuity flag 312 is reset at logic "0", the support
frames 130 and 132 of the optical unit 116 are stopped at the intital positions. On
the other hand, when the continuity flag 312 is set at logic "1", the support frames
130 and 132 of the optical unit 116 begin to move to the right in Figure 3 for the
next cycle of copying simultaneously with (or as will be described below, after the
lapse of a predetermined period of time from) the stopping of their leftward movement
in Figure 3. At this time, the paper delivery action for the next copying cycle has
already ended, and the leading edge of a copying paper for the next copying cycle
stops in abutment against the nip position of the pair of stationary conveyor rollers
84 and 86. How the action of deliverying paper for the next copying cycle is started
will be described in detail hereinafter.
[0042] When the continuity flag 312 is set at logic "1", the rotating drum 18 continues
to rotate for the next copying cycle. But when the continuity flag 312 is reset at
logic "0", the rotating drum 18 is stopped at a suitable time after it has undergone
the cleaning action of the cleaning blade 48 or the cleaning action of the developing
means 40 (this feature will be described further hereinafter).
[0043] When the semi-automatic document supplying and discharging device 6 is utilized,
the main frame structure 16 is brought to its operating position shown in Figures
1 and 3. The operator manually introduces a document into the introducing portion
144 of the conveying passage 140. As a result, the detecting means 258 detects the
inserted document to produce a document insertion signal. When the document insertion
signal is produced, the print switch 284 (Figure 6) is instantaneously closed, and
quite the same procedure as in the case of producing the aforesaid copying process
performance signal is performed in the main body 2 of the copying apparatus.
[0044] On the other hand, in the semi-automatic document supplying and discharging device
6, the motor 188 is energized upon the production of the document insertion signal,
thereby rotating the driven roller 164 of the conveying roller unit 160 and the conveying
belt mechanism 170. At the same time, the solenoid 168 is energized to press the follower
roller 166 of the conveying roller unit 160 against the driven roller 164 and simultaneously
cause the first regulating member 162 to move away from the introducing portion 144
thereby permitting advancing of the document. Thus, the inserted document is conveyed
to the main portion 142 from the introducing portion 144.
[0045] When the detecting means 258 has detected the passage of the trailing edge of the
inserted document past the detecting position of the detecting means 258, a first
counter 332 for the document conveyance included in the processing means 306 begins
to count clock pulses supplied from the clock pulse supplying source 318. When the
counter 332 has counted a predetermined number, the solenoid 168 is deenergized.
[0046] When the detecting means 264 detects the leading edge of the document conveyed by
the conveying belt mechanism 170, the motor 188 is deenergized. But the document further
advances owing to inertia, and stops when its leading edge makes contact with the
second regulating member 192. Thus, the document is positioned as required on the
transparent plate 12.
[0047] The motor 188 is energized when the detecting means 232 has detected the passage
of the trailing edge of the copying paper past the detecting position of the detecting
means 232 after the copying process is performed in the main body 2 of the copying
paper through a predetermined number of cycles and the continuity flag 312 is reset
at logic "0" (namely, when the exposure of the document in the final cycle of the
copying process has ended). Simultaneously, the solenoid 196 is energized to cause
the second regulating member 192 to move away from the main portion 142, thereby permitting
advancing of the document. Thus, the document is discharged by the conveying belt
mechanism 170 from the main portion 142 through the curved discharging portion 146.
[0048] When the detecting means 266 has detected the passage of the trailing edge of the
document past the detecting position of the detecting means 266, a second counter
334 for document conveyance included in the processing means 306 begins to count clock
pulses supplied from the clock pulse supply source 318. When the counter 334 has counted
a predetermined number, the motor 188 and the solenoid 196 are deenergized.
[0049] When the next document has been introduced into the introducing portion 144 by hand
before the previous document is discharged from the transparent plate 12, the aforesaid
procedure is not immediately performed even when the detecting means 258 has detected
the document and produced a document insertion signal. The aforesaid procedure is
performed when the previous document has been completely discharged (i.e., after the
counter 334 has counted a predetermined number).
Dectection of troubles in the conveying of the copying paper and the document
[0050] In the main body 2 of the copying apparatus, conveying troubles such as jamming of
the copying paper are detected in the following instances.
(1) When the delivery of a copying paper by the supply roller 64a or 64b is started,
a first paper jam counter 336 included in the processing means 306 begins to count
clock pulses supplied from the clock pulse supply cource 318, but the counter 336
has counted a predetermined number without being reset by the detection of the leading
edge of the copying paper by the detecting means 232.
(2) When the detecting means 232 has detected the leading edge of the copying paper,
a second paper jam counter 338 included in the processing means 306 begins to count
clock pulses supplied from the clock pulse supply source 318, but the counter has
counted a predetermined number without being reset by the detection of the leading
edge of the copying paper by the detecting means 234.
(3) The detecting means 244 has detected the wrapping of the copying paper about the
photosensitive member 20.
(4) The detecting means 244 has detected the wrapping of the copying paper about the
photosensitive member 20 and the detecting means 234 has detected the copying paper
(this means that two sheets of copying paper are delivered simultaneously, and one
of them wraps about the photosensitive member 20).
(5) When the detecting means 234 has detected the leading edge of the copying paper,
a third paper jam counter 340 included in the processing means 306 begins to count
clock pulses supplied from the clock pulse supply source 318, but the counter 340
has counted a predetermined number without being reset by the detection of the leading
edge of the copying paper by the detecting means 236.
(6) When the detecting means 236 has detected the leading edge of the copying paper,
a fourth paper jam counter 342 included in the processing means 306 begins to count
clock pulses supplied from the clock pulse supply source 318, but the counter 324
has counted a predetermined number without being reset by the detection of the trailing
edge of the copying paper by the detecting means 236.
[0051] In the semi-automatic document supplying and discharging device 6, jamming of a document
is detected in the following instances.
(1) When the motor 188 is energized for supplying the inserted document to the transparent
plate 12, a first document jam counter 344 included in the processing means 306 begins
to count clock pulses supplied from the clock pulse supply source 318, but the counter
344 has counted a predetermined number without being reset by the detection of the
leading edge of the document by the detecting means 264.
(2) When the motor 188 is energized for discharging the document from the transparent
plate 12, a second document jam counter 346 begins to count clock pulses supplied
from the clock pulse supply source 318, but the counter 346 has counted a predetermined
number without being reset by the detection of the leading edge of the document by
the detecting means 266.
(3) When the detecting means 266 has detected the leading edge of the document, a
third document jam counter 348 included in the processing means 306 begins to count
clock pulses supplied from the clock pulse supply source 318, but the counter 348
has counted a predetermined number without being reset by the detection of the trailing
edge of the document by the detecting means 266.
Control of the positioning of the cleaning blade
[0052] As already stated with reference to Figures 3 and 4, in the main body 2 of the copying
apparatus, a cleaning blade 48 made of suitable flexible material such as synthetic
rubber is disposed for removing the residual toner from the photosensitive member
20 in the cleaning zone 34 located around the rotating drum 18. The cleaning blade
48 is supported by a blade supporting mechanism 354 known
per se including a solenoid 352 as illustrated in a simplified form in Figure 4. When the
solenoid 352 is energized, the cleaning blade 48 is held at its operating position
shown by the solid line in Figure 4. When it is deenergized, it is held at its non-operating
position shown by the two-dot chain line in Figure 4. At the operating position shown
by the solid line in Figure 4, the cleaning blade 48 is pressed elastically against
the photosensitive member 20 on the rotating drum 18. On the other hand, at the non-operating
position shown by the two-dot chain line in Figure 4, the cleaning blade 48 is away
from the photosensitive member 20 on the rotating drum 18.
[0053] As already stated hereinabove, a magnetic brush type developing means 40 is disposed
in the developing zone 28 around the rotating drum 18 in the main body 2 of the copying
apparatus. As is well known to those skilled in the art, the magnetic brush-type developing
means 40 can be used not only for developing a latent electrostatic image formed on
the photsensitive member 20 but also, as a cleaning means, for removing the residual
toner from the photosensitive member 20 after the transfer. When the magnetic brush-type
developing means 40 is used as a cleaning means, the rotating drum 18 should additionally
be kept rotating even after the transfer so that that area of the photosensitive member
on which the toner remains after the transfer (i.e., that area where the toner image
is formed) passes through the developing zone 28 and thus undergoes the cleaning action
of the magnetic brushtype developing means 40; and then the next cycle of the copying
process should be started. Hence, the copying time necessarily becomes longer.
[0054] It will be easily understood on the other hand that when the residual toner on the
photosensitive member 20 is removed by using the cleaning blade 48, it is not necessary
to keep the rotating drum 18 rotating additionally, and therefore, the time required
for copying can be minimized. In the case of removing the residual toner from the
photosensitive member 20 by means of the cleaning blade 48, the photosensitive member
and/or the cleaning blade 48 tends to be degraded relatively early because the cleaning
blade 48 is pressed against the photosensitive member 20.
[0055] In the main body 2 of the copying apparatus, paper cassettes containing copying paper
sheets of various sizes are selectively mounted on the first cassette receiving section
54a and the second cassette receiving section 54b of the paper feeding device 52,
and copying paper sheets of various sizes are selectively delivered and conveyed through
the transfer zone 30. Some of these sizes are longer than the total length of the
photosensitive member 20, and the others are equal to, or smaller than, the photosensitive
member 20. As will be understood from the foregoing description about the basic operating
procedure of the copying apparatus, the length of a toner image formed on the photosensitive
member 20 is substantially equal to the length of a copying paper delivered.
[0056] In view of the aforesaid fact, when a copying paper conveyed through the transfer
zone 30 is a long one having a length larger than the total length of the photosensitive
member 20, the cleaning blade 48 is positioned at the aforesaid operating position
and thus performs its cleaning action. When a copying paper conveyed through the transfer
zone 30 is a short one having a length equal to, or smaller than, the total length
of the photosensitive member 20, the cleaning blade 48 is held at its non-operating
position, and the magnetic brush-type developing means 40 performs a cleaning action.
[0057] When the copying paper conveyed through the transfer zone 30 is a short one the cleaning
blade 48 is held at its non-operating position and is away from the photosensitive
member 20. Hence, the life of the photosensitive member 20 and/or the cleaning blade
48 becomes correspondingly longer. When the copying paper conveyed through the transfer
zone 30 is a long one, the cleaning of the residual toner is carried out by utilizing
the magnetic brush-type developing means 40. It is necessary therefore to rotate the
rotating drum 18 additionally after the transfer, and the copying time becomes correspondingly
longer. However, as will be understood from the foregoing description of the basic
operating procedure of the copying apparatus, when the copying paper conveyed through
the transfer zone 30 is a long one, the basic copying time, i.e., the time other than
the time during which the rotating drum 18 is additionally rotated is relatively short.
Hence, the prolongation of the copying time owing to the additional rotation of the
rotating drum 18 does not give rise to any practical problem.
[0058] With reference to Figure 8 showing a flow chart of controlling of positioning of
the cleaning blade 48 by the processing means 306 taken in conjunction with Figures
3, 4 and 7, it is judged in step n1-1 whether the aforesaid copying process performance
signal has been produced by the instantaneous closing of the print switch 284 (Figure
6), or the aforesaid document insertion signal has been produced by the detection
of the inserted document by the detecting means 258. Then, step n1-2 sets in. When
the aforesaid copying process performance signal or the document insertion signal
which induces the start of rotation of the rotating drum 18 is produced, it is judged
in step n1-2 whether the copying paper to be delivered is a long paper, namely whether
the length of the copying paper delivered is longer than the total length of the photosensitive
member 20. This judgement is made by (a) determining in which of the two conditions
the paper selection switch 286 (Figure 6) is (therefore which of the supply roller
64a and the supply roller 64b is actuated), and at the same time, (b) recognizing
the paper cassette 58a loaded in the first cassette receiving section 54a on the basis
of a signal from the discriminating means 208a, or recognizing the paper cassette
58b loaded in the second cassette receiving section 54a on the basis of a signal from
the discriminating means 208. When the copying paper delivered is a long one, step
n1-3 sets in. In step n1-3, the solenoid 352 is energized, and consequently, the cleaning
blade 48 is held at its operating position shown by the solid line in Figure 4. Then,
in step n1-4, the copying process described hereinabove is performed. When in step
n1-2, the delivered copying paper is a short one, step n1-4 sets in subsequent to
step n1-2, and therefore the solenoid 352 is maintained in the deenergized state and
the cleaning blade 48 is held at its non-operating position shown by the two-dot chain
line in Figure 4. In step n1-5, it is judged whether the transfer corona discharge
device 42 has been deenergized as above. When the transfer corona discharge device
42 is deenerigized, step n1-6 sets in. In step n1-6, it is judged whether the continuity
flag 312 is set at logic "1" and therefore the next cycle of the copying process is
successively carried out. When the continuity flag 312 is set at logic "1", step n1-7
sets in. In step n1-7, it is again judged whether the copying paper is a long paper
or not. When the copying paper is a long one, step n1-4 again sets in. When the copying
paper is a short one, step n1-8 sets in. In step n1-8, a cleaning counter 356 included
in the processing means 306 begins to count clock pulses supplied from the clock pulse
supply source 318. In step n1-9, it is judged whether the cleaning counter 356 has
counted a predetermined number. After the cleaning ounter 356 has counted the predetermined
number, step n1-4 again sets in. Before the cleaning counter 356 has counted the predetermined
number, the rotating drum 18 keeps rotating while the charging corona discharge device
38 and the transfer corona discharge device 42 are in the deenergized state. During
this time, the magnetic brush-type developing means 40 removes a toner remaining on
the photosensitive member 20 after the transfer. The aforesaid predetermined number
of the cleaning counter 356 is set such that the time from the beginning of counting
by the cleaning counter 356 becomes equal to the time required for the rotating drum
18 to rotate through at least one turn after the rear edge of that area of the photosensitive
member 20 in which the toner image is formed, i.e. that area of the photosensitive
member 20 with which the copying paper is brought into contact in the transfer zone,
has gone past the developing zone 28. When it is determined in step n1-6 that the
continuity flag 312 is reset at logic "0', step n1-6 is followed by step n1-10 in
which the cleaning counter 356 begins counting. In step n1-11, it is judged whether
the cleaning counter 356 has counted a predetermined number (this predetermined number
may be equal to, or larger than, the predetermined number in step n1-9). During the
time from the starting of counting by the cleaning counter 356 to the counting of
the aforesaid predetermined number, the rotating drum 18 keeps rotating while the
charging corona discharge device 38 and the transfer corona discharge device 42 are
maintained in the deenergized state. During this time, the residual toner is removed
from the photosensitive member 20 by the cleaning bladed 48 (in the case of a long
copying paper) or the magnetic brush-type developing means 40 (in the case of a short
copying paper). When the cleaning counter has counted the predetermined number, step
n1-12 sets in. In step n1-12, the solenoid 352 is deenergized if it is in the energized
state. Furthermore, in step n1-13, the rotation of the rotating drum 18 is stopped.
Control of continued delivery of the copying paper
[0059] With reference to Figures 3 and 5, in the copying apparatus described hereinabove,
when the next cycle of the copying process is performed successively after the previous
copying cycle, it is desired to start delivery of a copying paper for the next copying
cycle as early as possible after the paper delivery in the previous copying cycle.
On the other hand, the delivery of a copying paper in the next cycle of copying should
be started (a) in order to prevent overlapping of the trailing edge portion of the
copying paper fed in the previous copying cycle with the leading edge of the copying
paper delivered fed in the next cycle of copying in the first paper introducing passage
70a or the second paper introducing passage 70b, after the copying paper delivered
in the previous copying cycle and abutting at its leading edge against the nip position
of the pair of stationary conveyor rollers 84 and 86 begins to be conveyed by the
pair of conveyor rollers 84 and 86 whose rotation has been started, and (b) after
the trailing edge of the copying paper delivered in the previous copying cycle has
departed from the paper cassette 58a or 58b. As stated hereinabove, various paper
cassettes are selectively mounted on the first and second cassette receiving sections
54a and 54b, and the length of a copying paper to be delivered is various. When a
copying paper of a relatively large length is delivered, the trailing edge of the
copying paper departs from the paper cassette only after the lapse of a relatively
long period of time from the starting of conveying of the delivered paper by the pair
of conveyor rollers 84 and 86. When a relatively short copying paper is delivered,
the trailing edge of the copying paper departs from the paper cassette after the lapse
of a relatively short period of time from the starting of the conveying of the delivered
copying paper by the pair of conveyor rollers 84 and 86. When a copying paper is to
be delivered from the paper cassette 58b loaded in the second cassette receiving section
54b, the length of the copying paper may sometimes be shorter than the length of the
second paper introducing passage 70b extending from the paper cassette 58b to the
pair of conveyor rollers 84 and 86. Hence, it sometimes happens that when the leading
edge of the delivered copying paper has arrived at the nipping position of the conveyor
rollers 84 and 86, the trailing edge of the copying paper has already departed from
the paper cassette 58b.
[0060] In conventional copying apparatuses, the starting of delivery of a copying paper
in the next copying cycle is controlled on the basis of the longest copying paper
in order to meet the requirements (a) and (b) described above. Specifically, the delivery
of a copying paper in the next copying cycle is started after a period of time required
for the trailing edge of the longest copying paper to depart from the paper cassette
or a longer period of time after the initiation of rotation of the pair of conveyor
rollers 84 and 86 and therefore the initiation of conveying of the previous copying
paper. Such a conventional copying apparatus suffers from the inconvenience that if
the copying paper to be delivered is relatively short, the starting of delivery of
the copying paper in the next copying cycle becomes undesirably slow. It is important
that the leading edge of the copying paper in the next copying cycle should reach
the nip position of the pair of conveyor rollers 84 and 86 before the support frames
132 (and 130) of the optical unit 116, which have moved to the right in Figure 3 and
then to the left in Figure 3 in the previous copying cycle and thus have returned
to their initial positions, again begin to move to the right in Figure 3 for the next
cycle of copying and have advanced over the predetermined distance ℓ₃. Otherwise,
it would be impossible to perform the scanning exposure of the document and the conveyance
of the copying paper in synchronism. In contrast, when the copying paper is relatively
short, the reciprocating distance of the support frame 132 of the optical unit 116
in the previous copying cycle is relatively short, and therefore, the support frame
132 returns to its initial position relatively early. Hence, when the reciprocal movement
of the support frame 132 is started for the next copying cycle simultaneously with
or immediately after the returning of the support frame 132 to its initial position,
the copying paper delivered in the next copying cycle does not reach the nip position
of the pair of conveying rollers 84 and 86 before the support frame 132 moves the
predetermined distance ℓ₃. To avoid the occurrence of such a situation, the starting
of the reciprocation of the support frame 132 in the next copying cycle should be
delayed, and consequently, the copying time becomes longer than necessary.
[0061] The following improvement has been made in order to avoid the aforesaid disadvantage
of the conventional copying apparatus.
[0062] With reference to Figure 9 showing a flow chart of controlling the delivery of a
copying paper by the processing means 306 taken in conjunction with Figure 5, it is
judged in step n2-1 whether the aforesaid copying process performance signal has been
produced by the instantaneous closing of the print switch 284 (Figure 6), or whether
the aforesaid document insertion singal has been produced by the detection of the
inserted document by the detecting means 258. When the aforesaid copying process performance
signal or the document insertion signal has been produced, step n2-2 sets in. In step
n2-2, it is judged whether the paper selection switch 286 is in a first or a second
condition. When the paper selection switch 286 is in the first condition, step n2-3
sets in, and the supply roller 64a is rotated and the delivery of a copying paper
from the paper cassette 58a is started. Then, in step n2-4, it is judged whether the
detecting means 216 is closed or not. When the detecting means 216 is closed, step
n2-5 sets in, and the rotation of the supply roller 64a is stopped. Then, step n2-6
sets in and in this step, it is judged whether the detecting means 254 (Figure 3)
has been closed as a result of detecting the suport frame 132 of the optical unit
116. When the detecting means 254 is closed, step n2-7 sets in, and the pair of conveyor
rollers 84 and 86 are rotated to start the conveying of the copying paper. Then, step
n2-8 sets in, and it is judged whether the continuity flag 312 is set at logic "1".
In other words, it is judged whether the copying process is to be performed further.
When the continuity flag 312 is set at logic "1", step n2-9 sets in, and it is judged
whether the detecting means 232 has been closed as a result of detecting the leading
edge of the copying paper. When the detecting means 232 is closed, step n2-10 sets
in. In step n2-10, it is judged whether the shaft 62a having the supply roller 64a
fixed thereto is rotating. Such a judgement is made by determining whether the light
receiving element of the detecting means 210a alternately assumes a condition in which
it does not receive light and a condition in which it receives light and therefore
the production and dispearance of a signal are alternately repeated (when the shaft
62a is rotating), or the light receiving element of the detecting means 21a is continuously
maintained in a condition in which it does not receive light or a condition in which
it receives light and therefore the production or disappearance of a signal is continuously
maintained (when the shaft 62a is at rest). When the trailing edge portion of the
copying paper which has begun to be conveyed by the pair of conveyor rollers 84 and
86 is still in contact with the supply roller 64a, the supply roller 64a and the shaft
62a are rotated following the movement of the trailing edge of the copying paper being
conveyed [the shaft 62a having the supply roller 64a fixed thereto is connected to
a drive source by a suitable clutch means (not shown) such as an electromagnetic clutch
when it is rotated, but when the clutch means is in an inoperative condition and cut
off from the drive source, the shaft 62a can freely rotate at least in the delivery
direction, i.e. in the clockwise direction in Figure 5]. However, when the trailing
edge of the copying paper being conveyed leaves the supply roller 64a, the rotation
of the supply roller 64a and the shaft 62a comes to a stop. When the rotation of the
shaft 62a stops, step n2-11 sets in, and a delivery counter 358 included in the processing
means 306 begins to count clock pulses supplied from the clock pulse supply source
318. Thereafter, in step n2-12, it is judged whether the delivery counter 358 has
counted a predetermined number. When the delivery counter 358 has counted the predetermined
number, step n2-2 again sets in, and the delivery of a copying paper for the next
copying cycle is started. The above predetermined number of the delivery counter 358
is set such that the time required for the counter 358 to count the predetermined
number after the starting of counting is substantially equal to, or slightly longer
than, the time required for the trailing edge of the copying paper to leave the paper
cassette 58a after leaving the supply roller 64a.
[0063] On the other hand, when in step n2-2 the paper selection switch 286 is in the second
condition, n2-13 sets in, and the supply roller 64b and the pair of supply assisting
rollers 80 and 82 are rotated, and the delivery of a copying paper from the paper
cassette 58b is started. Then, in step n2-14, it is judged whether the detecting means
228 has been closed as a result of detecting the leading edge of the copying paper.
When the detecting means 228 is closed, step n2-15 sets in. In step n2-15, the first
paper conveyance counter 316 begins to count clock pulses supplied from the clock
pulse supply source 318. Then, it is judged in step n2-16 whether the counter 316
has counted a predetermined number. When the counter 316 has counted the predetermined
number, step n2-17 sets in and the rotation of the supply roller 64b is stopped (but
the delivery roller 64b is kept rotating incident to the movement of the copying paper
being conveyed). Thereafter, it is judged in step n2-18 whether the detecting means
216 is closed. When the detecting means 216 is closed, step n2-19 sets in, and the
rotation of the pair of supply assisting rollers 80 and 82 is stopped. Step n2-20
then sets in, and it is judged whether the detecting means 254 (Figure 3) has been
closed as a result of detecting the support frame 132 of the optical unit 116. When
the detecting means 254 is closed, step n2-21 sets in, and the pair of conveyor rollers
84 and 86 are rotated and simultaneously the pair of supply assisting rollers 80 and
82 are rotated. Thus, the conveyance of the copying paper is started. Then, step n2-22
sets in, and it is judged whether the continuity flag 312 is set at logic "1". When
the continuity flag 312 is set at logic "1", step 2-23 sets in, and it is judged whether
the detecting means 232 has been closed as a result of detecting the leading edge
of the copying paper. When the detecting means 232 is closed, step n2-24 sets in.
In step n2-24, it is judged whether the shaft 62b having the supply roller 64b fixed
thereto is rotating. Such a judgement is made on the basis of a signal from the detecting
means 210b as is the case with the judgement in step n2-10. When the rotation of the
shaft 62b is stopped, step n2-25 sets in, and the delivery counter 358 begins to count
clock pulses supplied from the clock pulse supply source 318. Then, in step n2-26,
it is judged whether the delivery counter 358 has counted a predetermined number.
This predetermined number may be the same as the predetermined number in step n2-12.
When the delivery counter 358 has counted the predetermined number, step n2-2 again
sets in, and the delivery of the copying paper for the next copying cycle is started.
[0064] According to the above-described control of continued delivery of a copying paper,
when the requirements (a) and (b) for starting the delivery of the next copying paper
are met, the delivery of the next copying paper is started without any substantial
delay irrespective of the length of the copying paper. Thus, the aforesaid disadvantage
in the conventional copying apparatus can be avoided.
[0065] In the illustrated embodiment, the departing of the copying paper from the paper
cassette 58a or 58b is detected by utilizing the detecting means 210a and 210b for
detecting the stopping of the rotation of the shafts 62a and 62b having the supply
rollers 64a and 64b fixed thereto and the delivery counter 358 associated with the
detecting means 210a and 210b. If desired, instead of this, the departing of the cop
ying paper from the paper cassette 58a or 58b can be detected by providing a suitable
paper detecting means capable of detecting a copying paper immediately below the paper
cassette 58a or 58b and detecting the passing of the trailing edge of the copying
paper past the detecting position of such detecting means.
Control of interrupting copying
[0066] When the semi-automatic document supplying and discharging device 6 is not used,
so-called "interruping copying" is possible without any problem in conventional apparatuses,
too. No technique, however, has been established to date which makes interrupting
copying possible without any problem even when the semi-automatic document supplying
and discharging device 6 is used. In contrast, in the copying apparatus interrupting
copying can be formed without any problem even in the case of using the semi-automatic
document supplying and discharging device 6.
[0067] This improvement achieved by this invention will be described with reference to Figure
10 showing a flow chart of controlling the semi-automatic document supplying and discharging
device 6 by the processing means 306 taken in conjunction with Figures 3 and 7. In
step n3-1, it is judged whether the detecting means 258 has produced a document insertion
signal by detecting a document inserted into the document inserting portion. When
the document insertion signal has been produced, the rotation of the rotating drum
18 and the delivery of a copying paper are started in the main body 2 of the copying
apparatus as already stated. When the detecting means 216 has been closed by the delivered
copying paper, the counted number of the copying process counter 320 included in the
processing means 306 is increased by one. On the other hand, as regards the semi-automatic
document supplying and discharging device 6, step n3-2 sets in when the document insertion
signal is produced. As a result, the motor 188 and the solenoid 168 are energized
to start conveying of the inserted document. Then, in step n3-3, it is judged whether
the document insertion signal has disappeared as a result of the passage of the trailing
edge of the document past the detecting position of the detecting means 258. When
the document insertion signal disappears, step n3-4 sets in, and the first counter
332 for document conveyance begins to count clock pulses supplied from the clock pulse
supply source 318. In step n3-5, it is judged whether the counter 332 has counted
a predetermined number. When the counter 332 has counted the predetermined number,
step n3-6 sets in, and the solenoid 168 is deenergized. Then, in step n3-7, it is
judged whether the detecting means 264 has been closed as a result of detecting the
leading edge of the document. When the detecting means 264 is closed, step n3-8 sets
in, and the motor 188 is deenergized. Thus, as stated hereinabove, the document is
positioned as required on the transparent plate 12. Then, in step n3-9, it is judged
which of an interrupting signal (logic "1") or a non-interrupting signal (logic "2")
the signal producing means 360 (Figure 7) is producing in response to the operation
of the interruption switch 288. When the operator has no intention of performing interrupting
copying, and therefore a non-interupting signal is produced, step n3-10 sets in. In
step n3-10, it is judged whether the continuity flag 312 is reset at logic "0". Step
n3-11 sets in when the counted number of the copying process counter 320 which is
increased one by one every time the delivery of the copying paper is performed in
the main body 2 of the copying paper (and therefore, every time the copying cycle
is performed) becomes equal to the counted number of the copy number counter 310 set
by the operator, and therefore, the copying process is performed through the desired
number of cycles and the continuity flag 312 is reset at logic "0". In step n3-11,
it is judged whether the detecting means 232 has detected the passing of the trailing
edge of the copying paper past the detecting position of the detecting means 232,
namely whether exposure in the final copying cycle has ended. When the exposure has
ended, step n3-12 sets in, and the motor 188 and the solenoid 196 are energized. As
a result, the discharging of the document from the transparent plate 12 is started.
Thereafter, in step n3-13, it is judged whether the detecting means 266 once closed
has been opened as a result of its detection of the passage of the trailing edge of
the document past the detecting position of the detecting means 266. When the detecting
means 266 is opened, step n3-13' sets in, and solenoid 196 is deenergized. Thereafter,
step n3-14 sets in, and it is judged whether the detecting means 258 has produced
a document insertion signal as a result of its detection of the insertion of the next
document. When no document insertion signal is produced, step n3-15 sets in, and the
motor 188 is deenergized. When the document insertion signal is produced, step n3-2
again sets in, and the conveying of the next document is started.
[0068] On the other hand, when the operator intends to perform interrupting copying and
operates the interuption switch 288 (Figure 6), the signal producing means 360 (Figure
7) produces an interrupting signal. When the signal interrupting signal is produced,
the addition of a count number to the copying process counter 320 is inhibited, even
if the delivery of a copying paper is performed in the main body 2 of the copying
apparatus and the detecting means 216 is closed. Step n3-19 is thus followed by step
n3-16. In step n3-16, it is judged whether the detecting means 232 has detected the
passage of the trailing edge of the copying paper past the detecting position of the
detecting means 232, namely whether exposure in the copying process at the time of
producing the interrupting signal has ended. When the exposure comes to an end, steps
n3-17, n3-18 and n3-19 which are the same as the steps n3-12, n3-13, and n3-15 are
performed, and thus, the document located on the transparent plate 12 at the time
of producing the interrupting signal is discharged. Then, step n3-20 sets in, and
it is judged whether a document insertion signal has been produced as a result of
the insertion of a document for interrupting copying before the discharging of the
aforesaid document. When the document insertion signal is produced, step n3-21 sets
in, and the print switch 284 is manually closed and step n3-23 sets in. This is for
the purpose of making the operator fully aware that it is the performance of interrupting
copying. If desired, in step n3-21, it is possible to energize a suitable display
lamp or the like so as to urge the operator to close the print switch 284 by hand.
On the other hand, when no document insertion signal is produced in step n3-20, step
n3-22 sets in, and it is judged whether a document insertion signal has been produced
as a result of the insertion of a document after the discharging of the aforesaid
document. When the document insertion signal is produced, the aforesaid step n3-23
sets in. In this step n3-23 and the following steps n3-24, n3-25, n3-26, n3-27, n3-28
and n3-29, the same processings as in steps n3-2, n3-3, n3-4, n3-5, n3-6, n3-7 and
n3-8 are carried out. As a result , the document for interrupting copying is positioned
as required on the transparent plate 12. On the other hand, in the main body 2 of
the copying machine, in step n3-20, the starting of the rotation of the rotating drum
18 and the delivery of a copying paper are inhibited, and the rotation of the rotating
drum 18 and the delivery of the copying paper are started for the first time in step
n3-23. Step n3-29 is followed by step n3-20. In step n3-20, it is judged whether the
detecting means 232 has detected the passage of the trailing edge of the copying paper
past the detecting position of the detecting means 232, namely whether exposure in
the interrupting copying process has ended. When the exposure comes to an end, step
n3-31 sets in, and it is judged whether an interrupting signal has been produced.
When the interrrupting signal is produced, steps n3-32, n3-33, n3-33', n3-34 and n3-35
which are the same as the above steps n3-12, n3-13, n3-13', n3-14 and n3-15 are performed,
and the document for interrupting copying is discharged from the transparent plate
12. When the step n3-34, a document insertion signal is produced as a result of the
insertion of the next document for interrupting copying, step n3-23 again sets in.
In step n3-36 following step n3-35, it is judged whether an interrupting signal has
been produced. When the interrupting signal is produced, step n3-22 again sets in.
On the other hand, when the operator has ended interrupting copying and operated the
interruption switch 288 (Figure 6) in order to return to ordinary copying whereby
the signal producing means 360 (Figure 7) produces a non-interrupting signal, step
n-3-36 is followed by step n3-1. Thus, when the document used before the interrupting
copying is inserted by hand, it is supplied to the transparent plate 12, and the copying
process is performed through the remaining number of cycles for this document.
[0069] On the other hand, when the operator operates the interruption switch 288 (Figure
6) before the step n3-31 whereby the signal producing means 360 (Figure 7) produces
a non-interrupting signal, the step n3-31 is followed by step n3-37. In step n3-37
and the following steps n3-38, n3-38', n3-39 and n3-40, the same processings as in
steps n3-12, n3-13, n3-13', n3-14 and n3-15 are carried out, and the document for
interrupting copying is discharged from the transparent plate 12. When in step n3-39,
a document insertion signal is produced as a result of the insertion by hand of the
document before interrupting copying, the above step n3-2 again sets in. Thus, the
document used before the interrupting copying is delivered to the transparent plate
12, and the copying process is automatically repeated for this document through the
remaining number of cycles.
Troubleshooting and display
[0070] This subject will be described with reference to Figures 10-A to 10-D which are flow
charts showing the controlling of the processing means 306 relating to troubles taken
in conjunction with Figures 3 and 7. In step n4-1, it is judged whether a trouble
has occurred in various constituent elements of the copying apparatus (for example,
the document illuminating lamp 118, the electrical heating means 106 of the heat fixing
device 104, the electrical heating element 273 for heating the photosensitive member
20, the temperature detecting means 277 for detecting the temperature of the heat
fixing device 104, and the detecting means 279 for detecting the temperature of the
surface or its vicinity of the photosensitive member 20). When a trouble such as wire
breaks has occurred in the temperature detecting means 277 and the temperature detecting
means 279, detecting devices 281 and 283 respectively supply trouble indicating signals
to the processing means 306 (this will be further described hereinafter). Furthermore,
when a trouble has occurred in other consituent elements, the detecting means 275
supplies a trouble indicating signal to the processing means 306. When a trouble has
occurred in the constituent elements in step n4-1, the details of the trouble (i.e.,
which of the constituent elements gets out of order) are stored in a trouble memory
362, and thereafter in step n4-3, the inhibition flag 314 is set at logic "1" (hence,
the operation of the copying machine is stopped). Thereafter, step n4-66 sets in.
[0071] When it is judged in step n4-1 that no trouble has occurred in the constituent elements,
step n4-4 sets in. In step n4-4, it is judged whether the key card 276 is inserted
in the key card inserting section 274 (Figures 1 and 2) (i.e. whether the signal producing
means 278 has produced a copying process performance permission signal). When the
key card 276 is not inserted, the fact that the key card 276 is not inserted is stored
in a key card memory 364 included in the processing means 306 in step n4-5, and thereafter
in step n4-6, the inhibition flag 314 is set at logic "1". Then, step n4-66 sets in.
[0072] When the key card 276 is inserted in step n4-4, step n4-7 sets in, and in step n4-7
it is judged whether the first document jam counter 344 is set (namely, whether it
is in condition for counting). When the counter 344 is set, the counter 344 performs
counting in step n4-8 and thereafter in step n4-9, it is judged whether the counter
344 has counted a predetermined number. When the counter 344 has counted the predetermined
number (namely when a document inserted by hand in the semi-automatic document supplying
and discharging device 6 has jammed during its feeding to the transparent plate 12),
the fact that the document jammed during feeding is stored in a document trouble memory
366 included in the processing means 306 in step n4-10. In step n4-11, the continuity
flag 312 is reset at logic "0", and in step n4-12, the counted number of the copying
process counter 320 is reduced to zero. Thereafter, in step n4-13, the inhibition
flag 314 is set at logic "1". Then, step n4-66 sets in.
[0073] The following fact must be noted with regard to the step n4-12. When the detecting
means 258 detects the document inserted by hand in the semi-automatic document supplying
and discharging device 6, the supplying of the document toward the transparent plate
12 is started, and simultaneously, the paper feeding operation of the paper feed device
52 is started in the main body 2 of the copying apparatus. When the detecting means
216 is closed by the copying paper supplied, the counted number of the copying process
counter 310 for indicating the number of copying cycles performed in the main body
2 of the copying apparatus is increased by one. This increment in the copying process
counter 310 is achieved before the counter 344 has counted the predetermined number.
Accordingly, when the document inserted by hand in the semi-automatic document supplying
and discharging device 6 jams during supplying to the transparent plate, the counted
value of the copying process counter 310 becomes zero in spite of the fact that no
copy is obtained because of document jamming. Accordingly, in the copying apparatus
improved in accordance with this invention, the counted number of the copying process
counter 320 is brought to zero in step n4-12, and thus the occurrence of the above
inconvenience is avoided.
[0074] When the counter 344 is not set in step n4-7, and when the counter 344 has not counted
the predetermined number in step n4-9, step n4-14 sets in. In step n4-14, it is judged
whether the first copying paper jam counter 336 is set. When the counter 336 is set,
the counter 366 performs counting in step n4-15, and thereafter in step n4-16, it
is judged whether the counter 336 has counted a predetermined number. When the counter
336 has counted the predetermined number (namely, when the copying paper jams upstream
of the detecting means 232), the fact that the copying paper jammed upstream of the
detecting means 232 is stored in a paper trouble memory 368 included in the processing
means 306 in step n4-17. Then, in step n4-18, the continuity flag 312 is reset at
logic "0", and thereafter in step n4-19, it is judged whether the counted value of
the copying paper counter 322 is 2 or more. If the counted number of the paper counter
322 is not 2 or more, step n4-20 sets in. In step n4-20, the inhibitor flag 314 is
set at logic "1", and thereafter, step n4-66 sets in. When the counted value of the
paper counter 322 is 2 or more, after the delay of a predetermined period of time
in step n4-21, the inhibition flag 314 is set at logic "1" in step n4-22. Then, step
n4-66 sets in.
[0075] With regard to these steps n4-19 to n4-22, the following fact should be noted. As
stated hereinabove, the paper counter 322 counts up by one as a result of the closing
of the detecting means 216 by the copying paper fed to the first or second paper instroducing
passage 70a or 70b from the paper feed device 52, and counts down by one when the
trailing edge of the copying paper has passed the detecting position of the detecting
means 236 disposed at the discharge end portion of the paper conveying passage (in
more detail, after the laspe of a predetermined period of time defined by the predetermined
number of the second paper conveyance counter 330 from the aforesaid time of passage).
Accordingly, the counted number of the paper counter 322 indicates the number of copying
paper sheets present in the first paper introducing passage 70a, the second paper
introducing passage 70b and the paper conveying passage. The fact that the counted
value of the paper counter 322 is 1 or 0 when the copying paper jams upwardly of the
detecting means 232 means that no copying paper exists downstream of the detecting
means 232. In such a case, the inhibition flag 314 is set at logic "1" in step n4-20
to stop the operation of the copying apparatus immediately. On the other hand, the
fact that the counted value of the paper counter 322 is 2 or more when the copying
paper jams upstream of the detecting means 232 means that a separate copying paper
different from the jamming paper exists downstream of the detecting means 232. In
such a case, a delay of a predetermined period of time is provided in step n4-21 to
continue the operation of the copying apparatus for a required period of time, and
the separate copying paper existing downstream of the detecting means 232 is discharged
into the sorter 10. Thereafter, in step n4-22, the inhibition flag 314 is set at logic
"1" to stop the operation of the copying apparatus.
[0076] When the counter 336 is not set in step n4-14, and when the counter 336 has not counted
the predetermined value, step n4-23 sets in, and in step n4-23, it is judged whether
the second paper jam counter 338 is set. When the counter 338 is set, the counter
338 performs counting in step n4-24, and thereafter, in step n4-25 it is jedged whether
the counter 338 has counted a predetermined number. When the counter 338 has counted
the predetermined number (namely, when the copying paper jams in a path from the detecting
means 232 to the detecting means 234 and/or the copying paper wraps about the photosensitive
member 20), step n4-26 sets in. In step n4-26, it is judged whether the detecting
means 244 detects the copying paper. When the detecting means 244 detects the copying
paper (namely, when the counting of the predetermined number by the counter 338 in
step n4-25 is attributed to the wrapping of the copying paper about the photosensitive
member 20), the wrapping of the paper about the photosensitive member 20 is stored
in the paper trouble memory 368 in step n4-27, and in step n4-28, the continuity flag
312 is reset at logic "0". Thereafter, in step n4-29, the inhibition flag 314 is set
at logic "1", and then step n4-66 sets in. When the detecting means 244 does not detect
the copying paper in step n4-26 (namely, when the counting of the predetermined number
by the counter 338 in step n4-25 is attributed to the jamming of the copying paper
in a path from the detecting means 232 to the detecting means 234), the jamming of
the copying paper between the detecting means 232 and the detecting means 234 is stored
in the paper trouble memory 368 in step n4-30, and in step n4-31, the continuity flag
312 is reset at logic "0". Thereafter, in step n4-32, the inhibition flag 314 is set
at logic "1", and then step n4-66 sets in.
[0077] When the counter has not counted the predetermined number in step n4-25, step n4-33
sets in. In step n4-33, it is judged whether the detecting means 244 detects the copying
paper. The detection of the copying paper by the detecting means 244 in step n4-33
means that the detecting means 244 has detected the wrapping of the copying paper
about the photsensitive member in spite of the fact that because of the detection
of the copying paper by the detecting means 234, the counter 338 has not counted the
predetermined number in step n4-25. Hence, this means that two sheets of copying paper
are fed simultaneously, and one of them wraps about the photosensitive member and
the other exists in the conveying passage. In such a case, the counted value of the
paper counter 322 is increased by 1 in step n4-34. As a result, the counted number
of the paper counter 322 is made equal to the number of copying paper sheets which
exist in the main body 2 of the copying apparatus and should therefore be removed
before resuming the copying process. Then, in step n4-35, the above fact is stored
in the paper trouble memory 368, and thereafter in step n4-36, the continuity flag
312 is reset at logic "0". Then, in step n4-37, the inhibition flag 314 is set at
logic "1", and thereafter step n4-66 sets in.
[0078] When the counter 338 is not set in step n4-23 and when the detecting means 244 does
not detect the copying paper in step n4-33, step n4-38 sets in. In step n4-38, it
is judged whether the third paper jam counter 340 is set. When the counter 340 is
set, the counter 340 performs counting in step n4-39, and thereafter, in step n4-40,
it is judged whether the counter 340 has counted a predetermined number. When the
counter 340 has counted a predetermined number (namely, when the copying paper has
jammed between the detecting means 234 and the detecting means 236), the fact that
the copying paper has jammed between the detecting means 234 and the detecting means
236 is stored in the paper trouble memory 368 in step n4-41. Then, in step n4-42,
the continuity flag 312 is reset at logic "0", and in step n4-43, the inhibition flag
314 is set at logic "1". Therafter step n4-66 sets in.
[0079] When the counter 340 is not set in step n4-38, and when the counter 340 has not counted
a predetermined number in step n4-40, step n4-44 sets in. In step n4-44, it is judged
whether the fourth paper jam counter 342 is set. When the counter 342 is set, the
counter 342 performs counting in step n4-45, and thereafter in step n446, it is judged
whether the counter 342 has counted a predetermined number. When the counter 342 has
counted the predetermined number (namely, when the copying paper has jammed during
the time from the arrival of the leading edge of the copying paper at the detecting
position of the detecting means 236 to the passage of its trailing edge past this
detecting position), this fact is stored in the paper trouble memory 368 in step n4-47.
Then, in step n4-48, the continuity flag 312 is reset at logic "0", and in step n4-49,
the inhibition flag 314 is set at logic "1". Thereafter, step n4-66 sets in.
[0080] When the counter 342 is not set in step n4-44 and when the counter 342 has not counted
the predetermined number in step n4-46, step n4-50 sets in. In step n4-50, it is judged
whether a trouble has occurred in the sorter 10. When a trouble has occurred in the
sorter 10, a signal showing this fact is fed from the detecting means 256 into the
processing means 306. When a trouble has occurred in the sorter 10, the occurrence
of the trouble in the sorter 10 is stored in a sorter trouble memory 370 included
in the processing means 306 in step n4-51, and in step n4-52, the continuity flag
312 is reset at logic "0". Then, the inhibition flag 314 is set at logic "1" in step
n4-53, and thereafter step n4-66 sets in.
[0081] When no trouble has occurred in the sorter 10 in step n4-50, step n4-54 sets in,
and in this step, it is judged whether the second document jam counter 346 is set.
When the counter 346 is set, the counter 346 performs counting in step n4-55, and
thereafter, in step n4-56, it is judged whether the counter 346 has counted a predetermined
number. When the counter 346 has counted the predetermined number (namely, when the
document moved away for discharge from the transparent plate 12 in the semi-automatic
document supplying and discharging device 6 has jammed before it reaches the detecting
device 266), the jamming of the discharged document before reaching the detecting
means 266 is stored in the document trouble memory 366 in step n4-57. After the delay
of a predetermined period of time in step n4-58, the inhibition flag 314 is set at
logic "1" in step n4-59, and thereafter step n4-66 sets in. The delay of a predetermined
period of time in step n4-58 permits the discharging of the copying paper conveyed
in the main body 2 of the copying apparatus.
[0082] When the counter 346 is not set in step n4-54, and when the counter 346 has not counted
the predetermined number in step n4-56, step n4-60 sets in. In step n4-60, it is judged
whether the third document jam counter 348 is set. When the counter 348 is set, the
counter 348 performs counting in step n4-61 and it is judged in step n4-62 whether
the counter 348 has counted a predetermined number. When the counter 348 has counted
the predetermined number (namely, when the document has jammed during the time from
the arrival of the leading edge of the discharged document at the detecting position
of the detecting means 266 to the time of passage of its trailing edge past this detecting
position), this fact is stored in the document trouble memory 366 in step n4-63. Then,
after the delay of a predetermined period of time in step n4-64, the inhibition flag
314 is set at logic "1" in step n4-65. Thereafter, step n4-66 sets in.
[0083] When the counter 348 is not set in step n4-60, and when the counter 348 has not counted
the predetermined number in step n4-62, step n4-66 sets in.
[0084] In step n4-66, it is judged whether a signal for the performance of the copying process,
i.e. the aforesaid copying process peformance signal produced by momentarily closing
the print switch 284 (Figure 6) by hand or the aforesaid document insertion signal
produced by the detection of the manually inserted document by the detecting means
258 in the semi-automatic document supplying and discharging device 6, is produced.
When the above signal is produced in step n4-66, step n4-67 sets in, and it is judged
whether the inhibition flag 314 is set at logic "1". When the inhibition flag 314
is not set (namely, when the copying process is ready for performance), step n468
sets in. In step n4-68, the continuity flag 312 is set at logic "1". Then, in step
n4-69, the counted number of the copy number setting counter 310 is displayed, and
in step n4-70, the counted number of the copying process counter 320 is displayed.
The counter number of the copy number setting counter 310 is displayed digitally in
the first display means 302 (Figure 6), and the counted number of the copying process
counter 320 is displayed digitally in the second display means 304 (Figure 6). When
the aforesaid signal is not produced in step n4-66, the process directly goes to step
n4-69 and n4-70.
[0085] On the other hand, when the inhibition flag 314 is set at logic "1" in step n4-67
(namely when the performance of the copying process is impossible), step n4-71 sets
in. In step n4-71, it is judged whether a trouble has occurred in the various constituent
elements of the copying apparatus. When a trouble has occurred in the constituent
elements, the datum stored in the trouble memory 362 is displayed in step n4-72. Such
displaying may include the energization of the serviceman call lamp 298 (Figure 6)
and the indication in the first display means 302 (Figure 6) of a specific constituent
element which has got out of order. Such a display in the first display means 302
may be "L1" as shown in Figure 11-A when such an element is the document illuminating
lamp 118.
[0086] When no trouble has occurred in the constituent elements in step n4-71, step n4-73
sets in. In step n4-73, it is judged whether the key card 276 (Figures 1 and 2) is
inserted in the key card inserting section 274 (Figures 1 and 2). When the key card
276 is not inserted, the datum stored in the key card memory 364 is displayed in step
n4-74. Such a displaying may be the energization of the key card lamp 294 (Figure
6).
[0087] When the key card 276 is inserted in step n4-73, step n4-75 sets in. In step n4-75,
it is judged whether a trouble has occurred in the conveying of the document in the
semi-automatic document supplying and discharging device 6. When a trouble has occurred
in the conveying of the document, the datum stored in the document trouble memory
366 is displayed in step n4-76. Such a displaying may include the energization of
the trouble lamp 300 and the displaying in the first display means 302 (Figure 6).
The display in the first display means 302 may, for example, be "D1" which is a combination
of "D" showing the document and the number "1" indicating the place of jamming (meaning
the upstream side of the detecting means 264), as illustrated in Figure 11-B.
[0088] When no trouble has occurred in the conveying of the document in step n4-75, step
n4-77 sets in. In step n4-77, it is judged whether a trouble has occurred in the conveying
of the copying paper in the main body 2 of the copying apparatus. When a trouble has
occcurred in the conveying of the copying paper, the datum stored in the paper trouble
memory 368 is displayed in step n4-78, and in step n4-79, the counted number of the
paper counter 322 is displayed. Displaying of the datum stored in the paper trouble
memory 368 may include the energization of the trouble lamp 300 (Figure 6) and displaying
in the first display means 302 (Figure 6). The display in the first display means
302 may be a combination of "P" showing the paper and the number "2" indicating the
place of jamming (or wrapping) (the number 2 means a place between the detecting means
232 and the detecting means 234). The counted number of the paper counter 322 is digitally
displayed in the second display means 304 (Figure 6), as shown in Figure 11-C. The
counted number, such as "2", of the paper counter 322 displayed digitally in the second
display means 304 means the number of copying paper sheets which exist in the main
body 2 of the copying apparatus and should be removed before resuming the copying
process.
[0089] When no trouble has occurred in the conveying of the copying paper in step n4-77,
step n4-80 sets in, and the datum of the sorter trouble memory 370, which relates
to the trouble in the sorter 10, is displayed. Such displaying may include the energization
of the trouble lamp 300 (Figure 6) and displaying in the first display means 302 (Figure
6). The display in the first display means 302 may, for example, be "S" which means
the sorter, as illustrated in Figure 11-D.
[0090] By the invention, as will be easily appreciated by reference to steps n4-66 and n4-67,
troubles are displayed only after the operation of the operator, i.e. the manual operation
of the print switch 284 (Figure 6) or the manual insertion of the document, and the
inconvenience of the conventional copying apparatuses can be avoided.
[0091] While the present invention has been described hereinabove with reference to the
accompanying drawings showing the preferred embodiments of the copying apparatus constructed
in accordance with this invention, it should be understood that the present invention
is no way limited to these specific embodiments, and various changes and modifications
are possible without departing from the scope of this invention as claimed.