BACKGROUND OF THE INVENTION
[0001] The present invention relates to an image recording apparatus wherein toner images
are transferred onto a recording sheet and then fixed thereon through an electrophotographic
method, and more particularly to an image recording apparatus capable of producing
even glossy images.
[0002] With regard to an image recording apparatus wherein toner images are transferred
onto a recording sheet and then fixed thereon through an electrophotographic method,
image recording apparatuses capable of forming color images have spread in addition
to those forming black and white images.
[0003] Even in a field of a recording sheet, formation of images on a transparent film has
spread in addition to that on an ordinary paper. A transparent light transmission
sheet on which images of graphics and graphs are formed by means of black or colored
toners is used in an overhead projector (OHP) so that the images thereon are projected
on a screen.
[0004] However, a light transmission sheet on which colored toner images are copied and
fixed by means of an ordinary electrophotographic copying machine has failed, when
projected by an OHP, to offer sharp projected color images. The reason why sharp projected
color images can not be obtained is that there are fine irregularities on the surface
of color toners deposited on a transparent film and the irregularities cause projected
light to be subjected to diffusion or diffused reflection and thereby color toner
portions are projected on a screen as a shade. A light transmission sheet that offers
sharp projected color images can be obtained by smoothing the surface of color toners
deposited on the sheet.
[0005] For the purpose of preparing a light transmission sheet that offers a sharp color
image, a light transmission sheet ejected from a copying machine after being subjected
to transferring and fixing of color toner images onto its transparent film in the
copying machine has been fixed again in an image quality improving apparatus provided
with a built-in heater and a pair of rollers for improving light transmitting property
and glossiness prepared separately in a way that the light transmission sheet passes
through the rollers while being sandwiched therebetween with a toner image surface
facing a thin film.
[0006] Even when color toners are transferred onto an ordinary paper and fixed thereon,
glossy color toner images can be obtained when the ordinary paper having thereon color
toner images passes through the aforementioned image quality improving apparatus with
toner images facing a thin film.
[0007] The aforementioned image quality improving apparatus prepared separately from a copying
machine is of a structure similar to that of a fixing unit provided in the copying
machine. It is therefore extremely desirable that a light transmitting property can
be enhanced or a gloss can be increased by feeding a light transmission sheet or a
color copy ejected from a copying machine again into the copying machine. However,
it is impossible to realize this easily because it is necessary to feed the light
transmission sheet or the color copy so that a thin film may be placed on the surface
of the light transmission sheet or the color copy.
① When a light transmission sheet is caused to pass through a feeding-out member and
a double-feed preventing member by using sheet feeding means of an image recording
apparatus again, creases are caused on a thin film, resulting in unevenness of gloss
and light transmitting property of the light transmission sheet.
② In the vicinity of a transfer unit in a conveyance path, there is positioned an
image carrier (a photoreceptor drum), and residual electric charges remaining after
image formation cause creases and dog-ears on a thin film, when it passes therethrough,
resulting in jam troubles and unevenness of a gloss and a light transmitting property.
③ In order for the toner image surface and a thin film to be fed together while they
face each other, fixed recording materials are fed again while they are sandwiched
between the thin film applied by a film applying unit and a film support. However,
depending upon a way of feeding, dog-ears or creases are generated, resulting in jam
troubles or unevenness of a gloss and a light transmitting property.
④ When a toner image surface and a thin film pass through a fixing unit while they
face and are in contact each other, a pair of rollers facing each other which lack
elasticity neither give smoothness to toners nor improve glossiness and light transmitting
property.
⑤ When a toner image surface and a thin film pass through a fixing unit while they
face and are in contact each other, creases are generated and uniform gloss and light
transmitting image screen can not be obtained if the relation of the hardness between
an upper roller and a lower roller is not established pertinently.
⑥ When feeding again recording materials facing a thin film by using sheet feeding
means of an image recording apparatus again, it is not possible to fix again due to
troubles in conveyance caused when the thin film and recording materials pass through
a transfer unit facing an image carrier.
⑦ When enhancing light transmitting property and glossiness by using again a fixing
unit which has fixed toner images, the conveyance speed for recording materials in
fixing which is too low fails to improve smoothness of an adhering toner surface.
⑧ In re-fixing whose purpose is to enhance a light transmitting property and glossiness,
satisfactory conditions for re-fixing need to be that a temperature on the surface
of a roller facing a thin film is within a range of 100°C - 160°C and a rubber hardness
of the roller is not more than 90° in surface hardness ASKER C. However, fixing conditions
for forming matted images through an ordinary high speed copying do not satisfy the
conditions mentioned above. Therefore, it is not possible to use, without taking any
action, the fixing unit which has formed fixed toner images.
SUMMARY OF THE INVENTION
[0008] An object of the invention is to solve the problems ① - ⑧ mentioned above and to
provide an image recording apparatus wherein it is possible to improve a gloss and
a light transmitting property by feeding thereinto again a light transmission sheet
or a color copy which has been subjected to fixing.
[0009] The invention is to provide an image recording apparatus solving the aforementioned
problems, and the first invention which has solved the problem described in the above-mentioned
item ① is to provide an image recording apparatus comprising a sheet feeding means,
an image forming means that transfers toner images formed on an image carrier onto
a recording material fed by the sheet feeding means and a fixing means that fixes
the recording material having thereon transferred toner images, wherein the recording
material is fed again in a manner that a toner surface of fixed recording material
is caused to face a thin film and is sandwiched between the thin film and a film support,
and the film support is caused to face a feed-out member of the sheet feeding means
and the thin film is caused to face the double-feed preventing means, so that the
recording material may pass through the fixing means again for smoothing the toner
images.
[0010] The second invention which has solved the problem described in the above-mentioned
item ② is to provide an image recording apparatus comprising a sheet feeding means,
an image forming means that transfers toner images formed on an image carrier onto
a recording material fed by the sheet feeding means and a fixing means that fixes
the recording material having thereon transferred toner images, wherein a toner surface
of the aforementioned fixed recording material is sandwiched between a thin film and
a film support in a way that the toner surface faces the thin film, and the aforesaid
sheet feeding means is driven again with the film support facing the image carrier
mentioned above so that the recording material may pass through the fixing means again
for smoothing the toner images.
[0011] The third invention which has solved the problem described in the above-mentioned
item ③ is to provide an image recording apparatus comprising a sheet feeding means,
an image forming means that transfers toner images formed on an image carrier onto
a recording material fed by the sheet feeding means and a fixing means that fixes
the recording material having thereon transferred toner images, wherein a toner surface
of the fixed recording material is sandwiched between a thin film applied by a film
applying unit and a film support in a way that the toner surface faces the thin film
and the above-mentioned sheet feeding means is driven again with the aforementioned
film-applied portion taking the lead so that the recording material may pass through
the fixing means again for smoothing the toner images.
[0012] The fourth invention which has solved the problem described in the above-mentioned
item ④ is to provide an image recording apparatus comprising a sheet feeding means,
an image forming means that transfers toner images formed on an image carrier onto
a recording material fed by the sheet feeding means and a fixing means that fixes
the recording material having thereon transferred toner images, wherein a toner surface
of the aforementioned fixed recording material is sandwiched between a thin film and
a film support in a way that the toner surface faces the thin film, and the above-mentioned
sheet feeding means is driven again with the aforementioned thin film facing an elastic
fixing member of the fixing means so that the recording material may pass through
the fixing means again for smoothing the toner images.
[0013] The fifth invention which has solved the problem described in the above-mentioned
item ⑤ is to provide an image recording apparatus comprising a sheet feeding means,
an image forming means that transfers toner images formed on an image carrier onto
a recording material fed by the sheet feeding means and a fixing means that fixes
the recording material having thereon transferred toner images, wherein a toner surface
of the aforementioned fixed recording material is sandwiched between a thin film and
a film support in a way that the toner surface faces the thin film, and the above-mentioned
sheet feeding means is driven again so that the recording material may pass through
the aforementioned fixing means having upper and lower conveyance members which are
different in hardness in a way that a conveyance member which comes in contact with
the film support is harder to be not less than 90° in surface hardness ASKER C at
the surface again, for smoothing the toner images.
[0014] The invention is to provide an image recording apparatus wherein the aforementioned
problems have been solved and, the sixth invention which has solved the problem described
in the above-mentioned item ⑥ is to provide an image recording apparatus comprising
a sheet feeding means, an image forming means that transfers toner images formed on
an image carrier onto a recording material fed by the sheet feeding means and a fixing
means that fixes the recording material having thereon transferred toner images, wherein
the sheet feeding means and the fixing means are operated while the image forming
means is kept to be out of operation, and a toner surface of the aforementioned fixed
recording material is sandwiched between a thin film and a film support in a way that
the toner surface faces the thin film, and the above-mentioned sheet feeding means
is driven again so that the recording material may pass through the fixing means again
for smoothing the toner images.
[0015] The seventh invention which has solved the problem described in the above-mentioned
item ⑦ is to provide an image recording apparatus comprising a sheet feeding means,
an image forming means that transfers toner images formed on an image carrier onto
a recording material fed by the sheet feeding means and a fixing means that fixes
the recording material having thereon transferred toner images, wherein the sheet
feeding means and the fixing means are operated in a way that each of a conveyance
speed of the sheet feeding means and a conveyance speed of the fixing means is lower
than that in image forming, and a toner surface of the aforementioned fixed recording
material is sandwiched between a thin film and a film support in a way that the toner
surface faces the thin film, and the aforesaid sheet feeding means is driven again
so that the recording material may pass through the fixing means again for smoothing
the toner images.
[0016] In the eighth invention which has solved the problem described in the above-mentioned
item ⑧, the surface of a thin film is caused to face a roller with rubber hardness
of not more than 90° in surface hardness ASKER C whose fixing temperature is within
a range of 100°C - 160°C by sandwiching a toner image surface in fixing upside down
for re-fixing considering the features of a thin film surface. The invention provides
an image recording apparatus comprising a sheet feeding means, an image forming means
that transfers toner images formed on an image carrier onto a recording material fed
by the sheet feeding means and a fixing means that fixes the transferred toner images
on the recording material, wherein the sheet feeding means and the fixing means are
operated, and then the sheet feeding means is driven again with fixing roller conditions
(roller materials, load, nips etc.) of the fixing means set identical to those in
image forming and with a toner surface of the fixed recording material being sandwiched
between a thin film applied by a film applying unit and a film support in a way that
the toner surface faces the thin film, so that the recording material may pass through
the fixing means for re-fixing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Fig. 1 is a structural diagram showing an example of an image recording apparatus
of the invention. Fig. 2 is an illustration showing how a recording material to be
fed again is caused to face a thin film, Fig. 3 is an illustration showing re-feeding
conditions at a manual sheet-insertion section, Fig. 4 is an illustration showing
re-feeding conditions at a transfer section and Fig. 5 is an illustration showing
re-feeding conditions at a fixing section. Fig. 6 is an illustration showing conditions
before re-feeding (a) and those after re-feeding (b) for a light transmission film
(a transparency). Fig. 7 is a block diagram showing the control system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] An image recording apparatus of the invention which will be explained as follows
referring to examples is a color image recording apparatus having a function in which
transparency and glossiness of toner images are improved when a recording material
ejected after being fixed is fed again from a manual sheet-insertion section with
a toner image surface on the recording material facing a thin film prepared separately,
keeping step with function of the image recording apparatus for recording color images.
[0019] Construction of a color image recording apparatus of the invention and how color
images are formed will be explained as follows, referring to Fig. 1.
[0020] In the figure, the numeral 30 is an image carrier in a drum shape that is to say
a photoreceptor drum having OPC photoreceptor coated on a drum and being ground and
rotated clockwise. The numeral 35 is a scorotron charging unit that gives electric
charges to the photoreceptor on the surface of the photoreceptor drum 30, the numeral
40 is an area for imagewise exposure where a laser beam is projected so that it is
focused on the surface of the photoreceptor drum 30 by means of an optical system
for exposure.
[0021] A laser writing unit, for example, may be used for the optical system for exposure.
After color signals outputted from an image-reading unit are inputted in the laser
writing unit, a laser beam emitted from an unillustrated semiconductor laser is subjected
to rotational scanning by means of polygon mirror 41 in the laser writing unit, and
then is deflected by reflection mirror 43 through fϑ lens to be projected on the surface
of the photoreceptor drum 30 charged uniformly by the charging unit 35 mentioned above.
[0022] When scanning is started, on the other hand, the laser beam is detected by an index
sensor, modulation of the laser beam by means of the first color signals is started,
and modulated laser beam starts scanning the surface of the photoreceptor drum 30.
Therefore, both the primary scanning by means of the laser beam and the sub-scanning
by means of a rotation of the photoreceptor drum 30 start forming a latent image for
the first color on an image area on the photoreceptor drum 30. The latent image is
then subjected to reversal development under non-contact conditions in developing
means 36 (Y) containing, for example, yellow (Y) toners as the first color, thus,
a yellow toner image is formed on the surface of the photoreceptor drum 30. The toner
image obtained on the image area, while it is held on the surface of the photoreceptor
drum 30, passes under transferring means 37 and cleaning means 39 both of which are
staying away from the surface of the photoreceptor drum 30. After that, the next copy
cycle is started.
[0023] Namely, the photoreceptor drum 30 is charged again by the charging unit 35, then,
the second color signals outputted from a signal processing unit are inputted in the
writing unit mentioned above and writing on the surface of the photoreceptor drum
30 by means of the second color signals is conducted in the same manner as in the
case of the first color signals mentioned above, thus, a latent image is formed. This
latent image is subjected to reversal development under non-contact conditions in
developing means 36 (M) containing, for example, magenta (M) toners as the second
color, thus, a magenta toner image is formed. This magenta toner image is formed to
be superposed on the yellow toner image which has been formed already.
[0024] The toner image thus obtained on the image area, while it is held on the surface
of the photoreceptor drum 30, passes under transferring means 37 and cleaning means
39 both of which are staying away from the surface of the photoreceptor drum 30. After
that, the next copy cycle is started.
[0025] In the same manner as in the foregoing, writing by means of the third color is conducted
and a latent image is formed. This latent image is subjected to reversal development
under non-contact conditions in developing means 36 (C) containing, for example, cyan
(C) toners as the third color.
[0026] The cyan toner image is formed to be superposed on the yellow toner image and the
magenta toner image so that a color image may be obtained. Developing means 36 (BK)
containing black toners is further provided, and when a black toner image is further
formed to be superposed in the same manner as in the foregoing, a color image with
high image quality can be obtained.
[0027] As described above, charging by means of charging unit 35 provided around photoreceptor
drum 30 and itself, exposure by means of a laser writing unit for each color and development
processing by means of developing means 36 (Y), (M), (C) and (BK) are conducted for
each color, namely four times in total for forming a color toner image which is obtained
by superposing each color image on the image area on the surface of the photoreceptor
drum 30.
[0028] The numerals 61 and 62 represent conveyance paths through which a recording material
is conveyed one sheet by one sheet. With regard to recording materials loaded in sheet
feeding cassette 50, leading edges thereof are lifted by an unillustrated sheet lifting
plate, the uppermost sheet is fed out by feed-out roller 51 and then is conveyed,
after being separated by double-feed-preventing rollers 52a and 52b, through conveyance
paths 61 and 62 to the point of registration rollers 53a and 53b where the recording
material stops provisionally.
[0029] The registration rollers 53a and 53b feed out the recording material synchronizing
with a toner image on the photoreceptor drum 30 so that the toner image may be transferred
onto the recording material at the transferring means 37.
[0030] The transferring means 37 in the present example is composed of endless belt 373
spread over rotating rollers 371 and 272 and charging means 374 for image-transferring
provided at the position that is behind the belt 373 and faces the transferring area.
When transferring images, the transferring means presses the recording material that
moves while keeping in contact with the belt 373 onto the photoreceptor drum 30 and
the charging means 374 positioned behind transfers toner images onto the recording
material. The recording material on which image-transferring has been finished is
separated from the belt 373 by roller 372, conveyed to fixing means 70 through conveyance
belt 63 and ejected from the apparatus after being fixed.
[0031] On the other hand, blade 39A of the cleaning means 39 keeps in contact with the surface
of the photoreceptor drum 30 from which the recording material has been separated,
and removes toners staying thereon. After completion of removal of residual toners,
the blade is moved away from the surface of the drum again for the following process
of color image forming.
[0032] The transferring means 37 which has finished transferring is moved away from the
photoreceptor drum 30 to the position shown with dotted lines.
[0033] When improving light transmitting property and glossiness of an image on the recording
material ejected after the above-mentioned process, the recording material is conveyed
again as follows.
[0034] Fig. 2 shows a means for causing a recording material to be conveyed again to face
a thin film, and the means is prepared separately as sandwiching means F wherein thin
film F1 such as, for example, a polyester film or a polyimide film having a thickness
of not more than 50 µm and heat resisting property causing less toner deposition and
film support F2 such as a sheet of paper or a resin sheet having a thickness greater
than that of F1 and heat resisting property are included and an edge of the thin film
F1 and that of the film support F2 are pasted together at joining portion F3. Recording
material T to be conveyed again is sandwiched in the sandwiching means F with a toner
image surface facing the thin film F1.
[0035] For conveying again in an image recording apparatus in the present example, when
a re-feeding selection button provided on an operation panel of the image recording
apparatus is pressed, an image forming mode (copy mode) explained previously may be
changed to a re-feeding mode.
[0036] In the re-feeding mode, operations such as charging, imagewise exposure and developing
are not performed but feeding operation by means of a sheet feeding means from a manual-insertion
portion and fixing operation by means of a fixing means only are performed.
[0037] Fig. 3 shows how a recording material is fed again in a manual sheet insertion portion,
wherein recording material T sandwiched in sandwiching means F is inserted into a
manual sheet insertion portion with joining portion F3 as a leading edge, namely in
a way that the joining portion F3 hits a sheet feeding means, and with film support
F2 touching feed-out roller 64.
[0038] When a copy start button is pressed under the condition that sandwiching means F
is detected by sensor S1 provided on the manual sheet insertion portion, a sheet feeding
means starts operating and re-feeding is conducted by the rotation of feed-out roller
64. Since the re-feeding is conducted with joining portion F3 as a leading edge, it
is avoided that an edge of thin film F1 is dog-eared or folded to create creases.
[0039] Since the turning force of the feed-out roller 64 is transferred only to the film
support F2 which is in contact with the feed-out roller and thereby sandwiching means
F is moved along the conveyance path, no load is applied on the thin film F1 and thereby
no crease is created thereon.
[0040] The sandwiching means F fed out by the feed-out roller 64 is transported to double-feed-preventing
rollers 65a and 65b and further to registration rollers 53a and 53b in succession
to be transported. Even in this case, film support F2 is in contact with roller 65a
which is a driving roller in double-feed-preventing rollers 65a and 65b and thin film
F2 is in contact with stationary roller 65b which is connected to a torque limiter
and prevents double feeding. Therefore, no crease is created on the thin film F1 though
the force for pulling the thin film is applied on it.
[0041] In a re-feeding mode, registration rollers 53a and 53b have only the function for
feeding and film support F2 is in contact with driving roller 53a among registration
rollers 53a and 53b, while thin film F1 is in contact with driven roller 53b. Therefore,
the thin film F1, when it passes through the area of the registration roller 53a,
is neither be creased nor be dog-eared.
[0042] Fig. 4 is an illustration showing the state of re-feeding at the transferring portion.
[0043] In a re-feeding mode, transferring belt 373 is positioned at the point (shown with
dotted lines in Fig. 1) that is away from the photoreceptor drum 30 and rotates. Sandwiching
means F is transported while keeping in contact with the transferring belt 373 and
passes through the transferring section to move to adjoining conveyance belt 63. When
the sandwiching means F passes through the transferring section, film support F2 faces
the photoreceptor drum 30. If the sandwiching means F passes through the transferring
section with thin film F1 facing the photoreceptor drum 30, the thin film F1 is attracted
on an electrostatic manner to the charged photoreceptor drum 30, causing creases or,
in the worst case, conveyance troubles caused by the attraction of the thin film.
[0044] When the sandwiching means F sandwiching and holding recording material T passes
through the transferring section with its film support F2 facing the photoreceptor
drum 30 as in the invention, it is free from the troubles mentioned above and can
be transported normally.
[0045] Fig. 5 is a key portion diagram showing how a toner image is smoothed while sandwiching
means F holding recording material T is being pinched and transported by rotating
fixing rollers 70a and 70b in the fixing means 70.
[0046] Upper roller 70a of the fixing means in the present example is an aluminum tube with
a thin wall having therein an infrared lamp as a heat source at the center thereof,
whose external surface is covered with a PFA tube, and surface temperature of the
upper roller is controlled to be at about 195°C by means of a sensor.
[0047] On the other hand, lower roller 70b is a roller having a superficial layer made of
rubber material such as silicone rubber having a thickness of about 5 mm, and the
surface of the lower roller is coated with Teflon. The lower roller rotates while
being in pressure-contact, through its rubber hardness of not more than surface hardness
ASKER C 90°, with the upper roller 70a. Heat is conducted from the upper roller 70a
to the lower roller 70b whose surface temperature is thereby kept at about 130°C.
[0048] When the sandwiching means F is sandwiched and re-fixed in the fixing means 70 as
described above, it was observed that the smoothness on the surface of a toner image
portion was changed for the better and thereby light transmitting property and glossiness
were improved.
[0049] Fig. 6 shows that the smoothness of the toner surface is improved after (b) re-feeding
compared with (a) before re-feeding, and thereby, when illuminated, light is transmitted
through toners and sharp color images are projected on a screen.
[0050] The inventors of the invention made tests changing conditions variously about the
upper and lower rollers of a fixing means in which the sandwiching means F is subjected
to re-fixing while being sandwiched. As a result, it was observed that the surface
hardness of the roller facing the film support F2 needs to be harder than that of
the roller facing the thin film F1, and the desirable condition for the hardness of
the roller facing the thin film F1 is 90° or less in surface hardness ASKER C. The
sandwiching means F, after being subjected to re-fixing, is ejected and then cooled,
and recording material T therein becomes available after being separated from the
thin film F1.
[0051] Another example of the invention will be explained next as follows.
[0052] In an image forming apparatus in the present example, an operation mode is changed
from an image forming mode (copy mode) explained previously to a re-fixing mode when
a re-fixing selection button provided on an operation panel of the apparatus is pressed.
[0053] A block diagram shown in FIg. 7 indicates a control circuit for the foregoing wherein,
when the re-fixing selection button is pressed, image forming means such as charging,
exposure, developing, transferring and cleaning means are caused to be out of operation,
while only feeding operation through a manual insertion portion performed by a sheet
feeding means and fixing operation of a fixing means are conducted. Programming is
established so that sheet feeding speed and fixing speed in the re-fixing mode may
be lower than those in the copy mode with regard to the sheet conveyance speed.
[0054] In the sheet feeding portion where F3 hits a sheet feeding means, sandwiching means
F fed out by feed-out roller 64 is conveyed along conveyance path 62 through double-feed-preventing
rollers 65a and 65b as well as registration rollers 53a and 53b. In this case, the
registration rollers 53a and 53b have only the function of feeding in the re-fixing
mode, and these feeding rollers rotate at a low speed to convey the sandwiching means
F to a transferring means.
[0055] In a re-fixing mode, transferring belt 373 is positioned at the point that is away
from the photoreceptor drum 30 and rotates. Sandwiching means F is transported while
keeping in contact with the transferring belt 373 and passes through the transferring
section to move to adjoining conveyance belt 63. In the re-fixing mode, image forming
means are out of operation and photoreceptor drum 30 is suspended to be on a non-charged
state. Further, charging means 374 for transferring is also out of operation. Therefore,
the sandwiching means F is not contaminated by toners and others.
[0056] The thin film F1 is attracted in an electrostatic manner to the charging means, causing
creases or, in the worst case, conveyance troubles caused by the attraction of the
thin film. However, since image forming means are out of operation as in the invention,
the sandwiching means F in which recording material T is sandwiched and held can be
conveyed normally without causing the problems mentioned above.
[0057] In the fixing means 70 in a copy mode, rollers rotate at the linear speed of about
140 mm/sec and a toner image is conveyed thereby with its surface facing upper roller
70a for satisfactory fixing.
[0058] In the re-fixing mode, on the other hand, a toner image faces a fixing means in a
manner contrary to that in a copy mode, and a linear speed of rollers is switched
to the low speed of about 20 mm/sec. Therefore, when thin film F1 passes through the
elastic lower roller 70b while touching it in the occasion that sandwiching means
F is ejected after being subjected to re-fixing, it was observed that the smoothness
on the toner surface of a toner image was changed for the better and light transmitting
property and glossiness were improved.
[0059] Further, speed of revolution of the motor was varied in many ways for the tests.
[0060] As a result, it was observed to be necessary to use, in a re-fixing mode, the linear
speed of a roller which is lower than that in a copy mode.
[0061] The examples mentioned above were conducted based on the results of the tests mentioned
above wherein excellent fixing was carried out at a high speed in a copy mode, while
uniform gloss was obtained in a re-fixing mode by turning the toner image surface
upside down and by changing the fixing speed.
[0062] Owing to the invention, it has become possible to enhance light transmitting property
and glossiness of an image fixed on a recording material by feeding the recording
material again in the image recording apparatus of the invention and by peeling off
a thin film of a sandwiching means from the recording material, consequently, an apparatus
prepared separately for enhancing light transmitting property and glossiness has fallen
into disuse.
1. An apparatus for refixing a toner image on a recording sheet, comprising
means for feeding a recording sheet;
image carrying means having an imaging surface on which a toner image is formed;
transferring means for receiving the sheet from the feeding means and for transferring
the toner image from the image carrying means onto the sheet;
fixing means for receiving the sheet from the transferring means and for fixing
the toner image on the sheet;
a carrier member including a thin film member and a film supporting member which
are so constructed to sandwich the sheet having the toner image therebetween; and
means for controlling the feeding means, the image carrying means, the transferring
means and the fixing means so that the carrier means is conveyed together with the
sheet having the toner image from the feeding means to the fixing means through the
transferring means and that the toner on the sheet is refixed by the fixing means.
2. The apparatus of claim 1, wherein the sheet is inserted between the thin film member
and the film supporting member so that the toner image on the sheet faces the thin
film member.
3. The apparatus of claim 2, wherein the film member and the film supporting member are
jointed at their one side, and the carrier member is so conveyed that the jointed
side become a leading edge.
4. The apparatus of claim 3, wherein the feeding means comprises a double feed prevention
means including a rotating roller and stop roller which are arranged in contact with
each other, and the carrier means is conveyed between the rotating roller and the
stop roller so that the thin film member faces the stop roller and the film supporting
member faces the rotating roller.
5. The apparatus of claim 3, wherein, when the carrier member is conveyed together with
the sheet, the control means controls the transferring means and the image carrying
means so that between the transferring means and the image carrying means is provided
a space to allow the sheet to pass therethrough.
6. The apparatus of claim 5, wherein the carrier means is so conveyed between the transferring
means and the image carrying means that the film supporting member faces the image
carrying means.
7. The apparatus of claim 3, wherein the fixing means comprises a fixing roller having
a rigid cylindrical surface and an elastic roller having an elastic surface made of
rubber which are arranged in contact with each other, and the carrier means is conveyed
between the fixing roller and the elastic roller so that the thin film member faces
the elastic roller.
8. The apparatus of claim 3, wherein the rotation speed of the fixing roller in the timer
of refixing is made slower than that in the time of ordinarily fixing to fix a toner
image at the first time.