BACKGROUND OF THE INVENTION
[0001] This invention relates to an image formation apparatus having a unit to develop electrostatic
latent images formed on an image carrier and a mechanism to recover waste toner.
[0002] In image formation equipment such as electronic photocopying equipment, an electrostatic
latent image is formed on a photosensitive agent which is the image carrier and this
latent image is developed by a developer. The toner used for this developing method
has been generally black. Recently, however, mono-color developing using where red,
blue and other toners are used by changing the developing unit for installation to
the main body of the equipment has been increasing. However, a compact image forming
unit which including a developing system has not been developed.
SUMMARY OF THE INVENTION
[0003] The object of this invention is to decrease the size of the unit which includes the
developing equipment irrespective of the life of the image carrier by configuring
the image formation unit with a first unit containing an image carrier and a second
unit consisting of a developer and a waste toner recovery container.
[0004] Especially, this investigation is intended for the easy replacement of the developing
unit and discarding of the waste toner by just replacing the second unit which includes
the developer.
[0005] Briefly described, in accordance with the present invention, an image formation apparatus
having a first unit consisting of an image carrier and at least a cleaner being held
to one supporter and a second unit consisting of a developer to develop an electrostatic
latent image formed on the image carrier, the said first and second unit being installed
removably to the image formation apparatus, is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The present will become more fully understood from the detailed description given
hereinbelow and the accompanying drawings which are given by way of illustation only,
and thus are not limitative of the present invention and wherein:
Fig. 1 is a schematic side sectional view of the electronic photocopying system according
to this invention, Fig. 2 is a general perspective view of the second unit, Fig. 3
is a general perspective view of the first unit, Fig. 4 is a perspective view of the
copying machine with no second unit installed, and Fig. 5 is a perspective view of
the copying machine with the second unit installed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0007] Fig. 1 is a schematic sectional view of an electronic photocopier according to this
invention.
[0008] At the approximate centre of the copying machine 1, a drum-shaped photosensitive
device 2 formed to generate a copied image is provided. The photosensitive device
2 is held with a drive mechanism, not shown, for rotation. Around the photosensitive
device 2, a charger 3, light focuser/transmitter 4, developer 5, transferer 6, and
cleaner 7 are arranged along the rotating direction to form the copying image. In
this copying machine 1, at least the photosensitive device 2, charger 3, and cleaner
7 are held in one case to configure the first unit 8. This first unit 8 is held with
a guide supporter, not shown, on the equipment main body side and can be taken out
or reinstalled by any one by using the mounting handle on the unit.
[0009] An original stand 9 which is used to set the original and expose it with the exposure
light source 10 is movably positioned on the copying machine 1. This original stand
9 is scanned in the lateral direction with a drive unit, not shown. The optical image
obtained by the irradiation with the exposure light source 10 is projected on the
optical conductive layer on the surface of the photosensitive device by the light
focuser/transmitter 4. By this, an electrostatic latent image is formed on the photosensitive
device 2 according to the image of the original and this latent image is visualized
by the developer 5, which is the second unit.
[0010] Then, the image visualized by the said developer 5 (image of the toner) is transferred
onto the transfer paper which is carried from the paper feeder at the proper time
by the transfer 6. At this time, about 20% of the toner remains on the surface of
the drum of the photosensitive device 2. In order to remove this toner and use the
drum for the next image forming process, a cleaner 7 is provided. This cleaner 7 pushes
an elastic cleaning blade 70 to the surface of the photoelectric device 2 to scrape
off the remaining toner on the rotating photosensitive device 2. The toner scraped
off with the cleaning blade 70 is received by the waste toner receiver 7a positioned
under the cleaning blade. At the position of this waste toner receiver 7a, a waste
toner feeder 7b is provided for rotation. The waste toner feeder 7b carries the toner
dropped to the waste toner receiver 7s in the direction of the rotating axis of the
photosensitive device to the one side of the first unit. On the one side, a feeder
7c to carry the toner whose carrying direction as shown in Fig. 3 makes a right angle
to the previous carrying direction is provided in connection with the above described
waste toner carrier 7b. This carrier 7c faces the waste toner recovery container 56
which is provided in a single unit with the developer 5 described later.
Especially, the outlet port provided in the carrier 7c and the opening of the waste
toner recovery container 56 are positioned to face each other.
[0011] On the other hand, the transfer paper which was sent to the transfer position is
separated from the surface of the drum of the photosensitive device 2 with the separator
11 after the transfer of the image and sent to the overheat fixer 13 along the feeding
guide 12. In the fixer 13, the image of the toner powder on the transfer paper is
fixed by heat and pressure and the transfer paper after fixing is discharged to the
paper discharger 14.
[0012] Fig. 2 is a general perspective view of the second unit consisting of the developer
5 and waste toner recovery container 56. When the second unit is mounted to the main
body of the copying machine, the cover 51 over the developing opening is separated
to expose the magnetic brush of the toner generated on the developing sleeve and to
mount it to the mounting position of the main body of the copying machine holding
the second unit mounting handle 52. Number 54 indicates a positioning boss to be locked
to the positioning hole 8a provided on the side of the first unit 8 and number 53
is a locking claw to hold the developer 5 when it is installed to the main body of
the copying machine.
Number 55 indicates the color of the toner at the time of mono-color copying and can
be seen from the indicating window 1b at the front cabinet 1a. Number 56 is a vessel
for recovering waste toner which is carried from the first unit and held in one unit
with the developing system 5. They are replaced at the same time. Number 57 is the
cover for the waste toner receiving port which is opened in the direction of the arrow
when the second unit is mounted. It prevents the waste toner from overflowing when
the unit is taken out. It is designed so that, when the above-described cover 57 is
opened, this opening becomes coincident with the discharge port of the feeder 7c of
the first unit.
[0013] Fig. 3 is a general perspective view of the first unit 8 on the main body of the
copying machine so as to be demounted from, or remounted to a main body of the copying
machine. The first unit 8, in at least one case as described above, has a drum of
photosensitive agent and a cleaner 7 to remove toner remaining on the surface of the
photosensitive device. The waste toner removed from the surface of the photosensitive
device 2 by the cleaner 7 is carried to the one side of the first unit by the feeder
7b, and then discharged from the discharge port by the feeder 7c. This feeder 7c is
provided with cover 7d which moves in the direction of the arrow to open or close
the discharge port. When the waste toner recovery container 56 provided in the second
unit reaches a specified position, the cover 7d is opened opening the discharge port.
The discharge port of the feeder 7c is provided so as to be coincident with the opening
of the waste toner recovery container 56 of the second unit.
[0014] Here, the second unit cannot be installed unless the first unit 8 is installed to
the main body of the copying machine. When the first unit 8 is installed to the main
body of the equipment, a guide for the second unit is configured. For this purpose,
the first unit 8 is provided with a guide 8b as shown in Fig. 3. This guide 8b provided
on the first unit 8 not only guides the second unit, but also serves to position the
developing magnetic brush precisely to the surface of the drum of the photoelectric
together with the positioning boss 54 provided in the second unit. Fig. 4 shows the
condition that the said first unit is mounted.
[0015] Mounting procedure for the second unit is shown below. The first unit 8 is mounted
to the main body of the copying machine 1. The second unit is inserted to the main
body of the copying machine with its bottom part advancing along the guide 1c formed
by a part of the frame of the main body of the copying machine. Thus the second unit
is led to the inner part by the guide 8b provided in the first unit 8 and connected
to the image unit driver, not shown, in the inner part of the main body of the copying
machine. At the same time, the positioning boss 54 of the second unit is fitted to
the positioning hole 8a of the first unit 8 and locked. Since it is not restrained
and may jump out, it is hitched to the catch 1d of the guide 1c of the frame of the
main body of the copying machine with the locking claw 53 provided on the unit.
[0016] Upon the completion of the second unit, the covers 7d and 57 provided respectively
at the discharge port of the feeder 7c to carry the waste toner on the first unit
8 and the opening of the waste toner recovery container 56 are opened so that the
discharge port and receiving port align with each other and the recovery of waste
toner to recovery container 56 becomes possible. Fig. 5 shows the condition where
the second unit is installed.
[0017] By the above configuration, the second unit is positioned to the first unit 8, and,
while the main body of the copying machine is working, the toner remaining on the
photosensitive device 2 is carried through each feeder and recovered to the recovery
container 56 held in the second unit. When the life of the second unit including the
developer 5 has expired, for instance, when the toner of the developer 5 has been
exhausted, only the second unit needs to be replaced. Therefore it is not necessary
to increase the volume of the second unit including the developer 5 as a consequence
of the life of the photosensitive device 2 in the first unit 8.
Therefore, the second unit needs not correspond to the first unit and can be small.
[0018] The recovery container 56 has no relation with the first unit 8 either and therefore
its size can be freely determined. It is advisable to determine the size of the waste
toner recovery container 56 based on the capacity of the developer 5 to contain the
toner. For instance, the capacity may be determined so that the toner of the developer
5 of the second unit is exhausted before the life of the photosensitive device 2 has
expired and the waste recovery container becomes almost filled with waste toner when
the second unit is replaced. In other words, the size of the recovery container 56
may be determined so that the recovery container 56 is almost filled with waste toner
when the first unit is replaced. Therefore, the service life does not have to be considered
when the second and first unit are replaced. Especially, the first unit can be designed
freely and can be small.
[0019] As described above, in the system according to this invention, when the toner has
been exhausted and the unit with a developer is replaced, the vessel to recover the
waste toner which was recovered while the said unit was working is also replaced and
therefore replacement is made in a short time and done easily. The image former is
divided into two unit which have extremely different lives and as a result, each unit
can be used effectively until its life has expired and can be small.
While only certain embodiments of the present invention have been described, it will
be apparent to those skilled in the art that various changes and modifications may
be made therein without departing from the spirit and scope of the present invention
as claimed.
[0020] There are described above novel features which the skilled man will appreciate give
rise to advantages. These are each independent aspects of the invention to be covered
by the present application, irrespective of whether or not they are included within
the scope of the following claims.
1. An image formation apparatus having a first unit comprising at least a cleaning
system held to one supporter and a second unit comprising a developing system to develop
electrostatic latent images formed on an image carrier, the said first and second
unit being able to be mounted to and demounted from the said image formation apparatus;
a feeder to carry developing agent used to remove toner from said image carrier being
provided on the said first unit side, and a recovery container to recover the used
developing agent carried by the said feeder provided in the said second unit.
2. The image formation apparatus of claim 1, wherein said feeding means is rotated
by rotation means so as to feed waste toner to said a side of said first unit.
3. The image formation apparatus of claim 1, wherein said feeding means feeds the
waste toner to an opening of said recovery compartment means.
4. The image formation apparatus of claim 1, wherein said first and second unit means
are removable from the body of said image formation apparatus.
5. The image formation apparatus of claim 1, wherein said first unit means is necessarily
positioned within the body of said image formation apparatus before said second unit
means is positioned within the body of said image formation apparatus.
6. The image formation apparatus pf claim 5, wherein said first unit means comprises
guid means through which said second unit means is positioned within the body of said
image formation apparatus.
7. An image formation apparatus comprising:
Image formation means for forming image corresponding to an original; first unit means
for visualizing the image using toner;
second unit means for recovering waste toner after used with said first unit means;
said first unit means being removable from the body of the image formation apparatus
independetly from both the volume of waste toner stored in said second unit means
and the life time of an image visualizing member of said first unit means;
so that said first unit means become compact irrespective of the property of said
second unit means.
8. The image formation apparatus of claim 7, wherein the volume of said second unit
means is independent from the volume of recovery compartment means of said second
unit means for receiving waste toner.
9. The image formation apparatus of claim 7, wherein the volume of said waste toner
recovery compartment means corresponds to the full volume of waste toner which is
waste from the toner provided from the said first unit means.
10. An image recording apparatus including
developing means for developing a latent image formed on an image carrier using a
toner material;
cleaning means for removing excess toner from said image carrier; and
container means for receiving residual toner removed by said cleaning means;
characterised in that said developing means and said container means are included in a common unit which
is removably mounted within the body of the apparatus.
11. An apparatus according to claim 10, characterised in that said cleaning means is arranged to remove said excess toner from said image carrier
after transfer of the developed image onto a recording medium, said image carrier
and cleaning means being included in a further unit which is removably mounted within
said body.
12. An apparatus according to claim 11 characterised in that said further unit includes a toner transfer device for transferring toner from said
further unit to said first-mentioned unit, and conveying means which is operable to
convey the removed toner to said toner transfer device.