JPS61100770A - Color copying device - Google Patents

Abstract

PURPOSE:To prevent a photosensitive body from quick deterioration by separating the wall surface of a transfer body from the photosensitive surface when a color copying device is stopped or waited. CONSTITUTION:When a spacer is arranged between a photosensitive drum 27 and a transfer drum 38 in accordance with the rotation of the drum, the transfer drum 38 is separated like an arc around a supporting shaft 90. The contact surface of the drum 27 contacted with the spacer 110 is the ground part of the drum body separated from the photosensitive body 28 and the contact surface does not exert influence upon the photosensitive body 28. Tapers are fitted to both the ends of the spacer 110 to load/unload the spacer 110 between the drums 27 and 28 smoothly on the basis of the rotation of both the drums 27, 38. To prevent the photosensitive surface from constant contact with a mylar, the spacer 110 has a home mark for detecting a home position of the photosensitive drum so as to be positioned between both the drums 27 and 38 also at the stop or wait of the copying device.

Description

[Detailed description of the invention] ■Field of invention The present invention relates to a transfer device in a color copying machine.

■Conventional technology In color copying machines, the original image is converted into three primary colors of paint,
In other words, it is exposed separately for yellow, magenta, and cyan.
Full-color coloring is achieved through additive color mixing, in which each color is developed and superimposed. This is for example.

First, an original image is exposed to light on a photosensitive surface through a blue filter, which is a complementary color to yellow, to form an electrostatic latent image corresponding to the strength of the yellow component. Transfer to. Next, the original image is exposed to light on the photosensitive surface through a green filter, which is a complementary color to magenta, to form an electrostatic latent image corresponding to the strength of the magenta component, which is then developed with magenta toner and visualized.
Transfer the yellow toner image onto the same recording paper.

Furthermore, through a red filter, a cyan toner image is similarly transferred onto the same recording paper, overlapping the yellow and magenta toner images.

Therefore, in order to obtain one full-color copy, three exposures and one transfer process are required, but the additive color mixture of these three color toner images was originally the same. Since the original image is separated into each component, they must be transferred to exactly the same position. Therefore, this type of color copying apparatus uses a transfer body to fix the recording paper. Generally, a transfer drum is used in which recording paper is wound and fixed around a cylindrical wall whose circumferential length is equal to the circumferential length of the photoreceptor of the photoreceptor drum. The photosensitive surface of the photosensitive drum and the recording paper of the transfer drum are in light contact with each other at the transfer position, so that the transfer onto the recording paper can be performed while rotating synchronously in opposite directions. A suitable level of contact pressure is required at this transfer position because there are problems such as insufficient transfer resulting in poor transfer, or excessive pressure contact and damage to the photoreceptor. Therefore, a flexible dielectric film was held in a cylindrical shape, and a transfer drum (Japanese Patent Application Laid-open No. 19752-1981) that obtains contact pressure by the elasticity of this film was developed.
No. 2) has been proposed. However, this transfer drum does not have a means for adjusting contact pressure, so it is not possible to obtain a contact pressure corresponding to one paper thickness.

As a solution to these inconveniences, the
There is 3351. In this case, the transfer drum is rotatably supported on one side of a support that is rotatable around a fixed axis, and tension of a spring is applied to the other side, and the above contact pressure is obtained by a moment around the fixed axis. . According to this, a substantially constant contact pressure can be obtained by the spring tension regardless of the paper thickness. Further, even if carrier or the like gets mixed in during transfer, the transfer drum retracts around the fixed shaft, so the photoreceptor and the wall surface of the transfer drum will not be damaged.

However, the contact of the transfer drum wall surface with the photosensitive surface is necessary only when transferring a toner image, and is harmful at other times, such as when the copying apparatus is on standby or stopped. When the copying apparatus is not used for a long period of time, the wall surface of the transfer drum is in pressure contact with the photosensitive surface of the photoreceptor, causing the photosensitive layer in that area to change in quality, resulting in band-like unevenness or the like in the copied image.

On the other hand, this type of transfer drum is equipped with a clamper that clamps the end of the recording paper in order to securely wrap and fix the recording paper. If this clamper protrudes from the peripheral surface of the transfer drum, it causes various problems such as damage to the photosensitive surface and peeling of the photosensitive member.

Therefore, conventionally, this clamper is embedded so that it does not protrude from the wall surface of the transfer drum. FIG. 6 is a sectional view showing this state. 1 is a recording paper that is wound and fixed. 72 is a support frame that supports a flexible dielectric in a cylindrical shape, 76 is a flexible dielectric, and 78 is a clamper, which opens and closes around a clamper shaft 78a.

This clamper is embedded in a groove provided in the support frame and does not protrude from the surface of the transfer drum. but.

Because there is a step or angle between the surface where the recording paper is clamped by the clamper and the surface where it is wrapped around the transfer drum wall surface, the elasticity of the recording paper causes the portion that does not follow the transfer drum wall surface and forms a mountain. 2 may occur. This mountainous portion 2 may be crushed and wrinkled during transfer, or may gradually stretch and cause color shift.

(Objective of the Invention) It is an object of the present invention to provide a copying apparatus that is provided with a separating means for separating the wall surface of the transfer member from the photosensitive surface when the above-mentioned contact is not required, thereby preventing early deterioration of the photoreceptor.

■Structure of the Invention In order to achieve the above object, in the present invention, the support body that rotatably supports the transfer drum is made rotatable around a fixed axis, and a spring tension or the like is used as a moment around the axis to expose the photosensitive material. In a copying apparatus configured to obtain contact pressure of the transfer drum wall surface against the surface; a protrusion protruding from the circumferential surface is provided at a predetermined position on the end of the transfer drum, and this protrusion is inserted between the photoreceptor drum and the photoreceptor surface. and the wall surface of the transfer drum. At this time, the surface of the photosensitive drum that is pressed by the protrusion is a surface other than the photosensitive surface that does not affect image formation.

In a preferred embodiment of the present invention, a clamper is installed so that the recording paper can be clamped on substantially the same surface as the transfer drum wall surface, and the projection is provided at a position where the clamper can be separated from the photosensitive surface.

As another example, the tiIIIM! by means of spring tension or the like by solenoid energization/deenergization control! A moment is applied to cancel the remote moment, and the transfer drum wall surface is separated from the photosensitive surface at a predetermined time.

4. Embodiment of the Invention FIG. 1 shows a schematic structure of a color copying apparatus embodying one embodiment of the present invention. A color copying machine separates an M* color image into yellow, magenta, and cyan components and develops each color individually, so it takes about three times as many copying steps as a normal monochrome (black) copying machine. Complete a copy of the sheet. For this reason, the developing section is composed of approximately three times as many elements as the monochrome copying apparatus.

This will be explained below with reference to the drawings.

In FIG. 1, reference numeral 12 denotes a contact glass on which a document is placed, and the document is viewed from above by a presser plate 10.

Below the contact glass 10, an exposure lamp 14 is mounted on the same carriage. Scanner 1 including a first mirror 16 etc.
5; second mirror 18; lens 20; third mirror 22; fourth mirror 24 and a filter unit 26. The filter unit 26 includes a blue filter plate 26B and a green filter plate 26G.
, a red filter plate 26R, an end plate supporting these filter plates, a shaft, a drive solenoid, a filter position sensor, etc.
One of B, 26G, and 26H is selectively positioned within the exposure optical path.

27 is a photoreceptor drum having a photoconductive photoreceptor 28 attached to the drum wall. Circulating around the photosensitive drum 27, there are a static elimination corona generator (static elimination charger) 30, a charging corona generator (static charger) 32, an erase lamp 34.
Yellow developer 36Y, magenta developer 36M, cyan developer 36c, transfer drum 38. A cleaning unit 39 and the like are arranged. Each developing device is equipped with a developing sleeve, etc., and a cleaning unit 39
It is equipped with a carrier collection magnet and a blade for cleaning residual toner using a trailing method.

The transfer drum 38 is a cylindrical wall with the same diameter as the photoreceptor drum, which is made of a metal molded support frame and a transparent flexible dielectric material (mylar) attached thereto.The transfer drum 38 is a cylindrical wall having the same diameter as the photoreceptor drum, and records are recorded using electrostatic attraction and a clamper that clamps the end. The paper is wrapped and fixed, and detailed explanation will be given later. Inside the transfer drum, there is a transfer corona generator (
transfer charger) 40 and precharge corona generator (precharger) 64. Mylar static elimination corona generator (
It is equipped with a Myra charger) 66. The buri charger 64 and the mylar static elimination charger 66 are configured to vibrate,
In order to prevent the generation of noise, etc., the corona generators are double corona generators, so they are paired with cylindrical walls sandwiched between them.

44 is the paper feed force cent, and the paper feed roller 42. Resist/
The roller 46 and the like are a paper feeding system.

A fixing device 50 is provided with a runner roller 60 having a built-in heater therein.

48 is a paper feed motor, 54 is a main motor, 56 is a developing motor, 58 is an optical system drive motor, 60 is a fixing motor,
68 is a fan motor.

An outline of the operation will be explained.

The original set on the contact glass 12 is sequentially scanned by the scanner 15 in the horizontal direction of the figure, and the reflected light is sent to the first mirror 16 . Second mirror 18. lens 20
．． Third mirror 22. Fourth mirror 24 and filter
An image is formed on the surface of the photoreceptor 28 (hereinafter referred to as a photoreceptor surface) mounted on the photoreceptor drum 27 via the filter plate C of the unit 26 (26B in the drawing). In scanning by the scanner 15, from the reflection position 13 of the document to the photosensitive surface 28
The second mirror is driven in the scanning direction at half the speed of the scanner 15 so that the optical path length is always constant. Scanner 15 and second mirror 18
is return-driven by the optical system drive motor 58 after the scan is completed.

After the photosensitive surface is neutralized by a neutralizing charger 30, it is charged to a constant potential by a charging charger 32.

Further, the erase lamp 34 removes the electric charge in the area outside the width of the recording paper.

The photosensitive drum 27 is a rotary drum provided on the rotating shaft.
The speed is detected by an encoder (not shown) and the scanner 1
5 (counterclockwise in the figure), and the photosensitive surface is exposed. When the photosensitive surface is irradiated with reflected light from the original, the surface potential changes depending on the intensity of the light, so I?
? An electric latent image is formed. This electrostatic latent image is visualized (hereinafter referred to as a toner image) using the respective toner in one of the yellow developer 36Y, magenta developer 36M, and cyan developer 36G. In FIG. 1, since the filter plate 26B is inserted into the exposure optical path, the yellow developer 36Y is selected and yellow toner is deposited and visualized.

Since the photosensitive drum 27 and the transfer drum are engaged by gears 82 and 83 as shown in FIG. 2, they rotate at equal speeds and in opposite directions. When a pulse of a rotary encoder (not shown) of the photoconductor drum rotation axis is detected and a predetermined timing is reached, the recording paper is fed out from the paper feed cassette 44 by the paper feed roller 42 and sent to the registration roller 46 at a constant speed. . When a paper sensor (not shown) provided near the registration roller detects the arrival of this recording paper, the paper feed motor 48 moves the recording paper to the registration roller 46.
is driven, and the recording paper is accelerated to twice the speed.

At this point, the clamper provided on the transfer drum 38 has a clamper opening/closing mechanism and a hook pushing plate (not shown).
It is mechanically opened by the action of , and the recording paper collides with it and is clamped. Acceleration of the paper by registration rollers 46 makes this clamp reliable.

At this time, if two or more sheets of paper are fed in an overlapped manner (multiple feeding), they will be deposited on the wall surface or photosensitive surface of the transfer drum 38.

This may cause scratches, mechanical distortion, or paper jams due to tearing of the recording paper. Therefore, a sensor (not shown) for detecting double feed is installed on the conveyance path leading to the recording paper transfer drum 38.
is installed, and when double feeding is detected, paper feeding is stopped.

The fed recording paper is loosened by a paper winding roller (not shown), and is tightly wound and fixed to the transfer drum wall surface by electrostatic attraction.

The toner image on the photosensitive surface is transferred to the recording paper on the transfer drum at the transfer position. Directly below the transfer charger 40 is the transfer position.

Describe the high-level copy process.

This copying apparatus is equipped with a monochrome copy mode in which yellow, magenta, and cyan are designated for copying in a full-color copy mode. First, regarding monochrome copying: For example, when monochrome copying of cyan is specified, the filter plate drive solenoid is energized, and the filter plate 2SR of red, which is the complementary color, is set in the exposure optical path. That is, the photosensitive surface 28 is exposed to light reflected from the original through the red filter plate 26R, and an electrostatic latent image is formed. Since the cyan developing device 36C is energized, the electrostatic latent image is developed with cyan toner and transferred onto the recording paper wound around the transfer drum. The recording paper on which the cyan toner image has been transferred is neutralized by a Mylar static elimination charger 66 that also functions to eliminate static electricity from Mylar and the recording paper, and when the clamper is opened by a hook-up plate (not shown), it is transferred to the transfer drum by a separating claw (not shown). The toner is then peeled off and sent to the fixing device 50 by a conveyance roller (not shown). In the fixing device 50, the cyan toner image on the recording paper is heated and fixed by a fixing roller 62 having a built-in heater, and then the cyan toner image is discharged onto the copy tray 52 via a paper discharge roller (not shown).

After the toner (cyan) image is transferred, the photoreceptor drum 27 rotates one more time for cleaning, and detects the home mark of a rotary encoder provided on the photoreceptor drum rotation shaft (not shown) in order to perform the next copying process. This becomes the home position.

Next, a case where full color copy mode is specified will be explained.

When a copying execution command is input, the first exposure - development - is carried out.
In the transfer process: The filter plate drive solenoid is blue filter plate 26B.
Select. As the photosensitive drum 27 rotates, the photosensitive surface is continuously charged with a static eliminating charger 30, uniformly charged with a charger 32, and exposed through an erase lamp 34. A yellow (complementary color to blue) electrostatic latent image is formed by the light reflected from the original, visualized with yellow toner at 36Y, and transferred to recording paper. Cleaning, neutralization, charging, and erasing are performed in the order starting from the photosensitive surface to which the yellow toner image has been transferred, followed by the second exposure-development-transfer process.

4 For the second time, the filter plate drive solenoid selects the green filter plate 26G, and the reflected light from the original passes through the filter plate, and in the same continuous process, an electrostatic latent image of magenta (complementary color of green) is formed on the photosensitive surface. , 36M
The image is visualized with magenta toner and transferred onto the recording paper on which the yellow toner image has been transferred. Cleaning, neutralizing, charging.

After erasing, a third exposure-development-transfer process is performed in a further continuous process.

The third time, red filter plate 26R was selected,
An electrostatic latent image of cyan, the complementary color of red, is formed on the photosensitive surface by the light reflected from the original document. The toner image visualized by the cyan toner in the cyan developing device 36G is superimposed on the recording paper 4 on which the yellow and magenta toner images have been transferred, and a full-color image is created by adding and mixing these yellow, magenta, and cyan toner images. It becomes a toner image.

Starting from the end of the recording paper, the recording paper is peeled off from the transfer drum by the separation charger 66 and the separation claw, fixed in the fixing device 50, and discharged to the copy tray 52 via the paper discharge roller.

The photoreceptor drum rotates one more time and is cleaned.

After the static electricity has been removed, it becomes the home position for the first copying process.

Incidentally, FIG. 2 shows a schematic perspective view of the vicinity of the transfer device, centering on the transfer drum 38, according to the present invention. This will be explained with reference to FIG.

Reference numeral 70 denotes a transfer drum support frame having a cylindrical shape with a cutout, leaving an annular portion 72 and a connecting portion 74 formed by aluminum molding or the like. A Mylar film (100μ) 76 is attached to this support frame 70 as a flexible dielectric material, and a cylindrical transfer drum 38 is formed.
is formed. The connecting portion 74 is provided with a clamper 78 that clamps the end of the recording paper, and the clamper 78 is rotatably fixed to a ramper shaft 78a. Clamper shaft 7
The end of 8a is a clamper opening/closing hook 78b, and the clamper 78 is opened by pushing this up with a hook pushing plate (not shown). The hook push-up play l- is provided on the support body 88 so as to be movable forward and backward, and acts on the clamper opening/closing hook at a predetermined timing. Further, the clamper 78 is pressed against the connecting portion 74 by a leaf spring 80 in order to clamp the recording paper with a predetermined force.

Since the transfer drum 38 is rotatably supported by supports 88 provided on both sides of the transfer drum 38, the gear 8 of the photoreceptor drum 27 is transferred via a gear 84 attached to one side of the ring portion 72.
2 and can rotate synchronously. These gears 82 and 84 have sufficiently high teeth and are engaged even when the transfer drum 38 is separated from the photosensitive drum 27, so that synchronization does not occur.

The left side view of FIG. 2 is shown in FIG. 3a. The support body 88 has three support rollers 86a, 86b, and 86c, and supports the end portion 72 so as to push it apart from the inside.

The supports 88 on both sides are coupled by a central shaft 87, and the coupling shaft 87 has a transfer charger 40. Blicharger 64.
A charger arm is attached to fix the mylar static elimination charger 66, and each charger is fixed by sandwiching this arm.

88a is a notch for maintenance, and a predetermined charger can be replaced by fixing the center shaft and rotating the charger arm. Therefore, the support roller 86
a, 86b, and 86c have suitably short lengths.

The support body 88 is rotatable around a support shaft 90,
The support 90 is held by a bearing 92 that is adjustable and semi-fixed to a slider guide 98 that is fixed to the main body of the copying machine. A slider 96 is engaged with the slider guide 98 so as to be horizontally movable, and the first limit hole 9δ
a, first limit pin 96a and second limit pin 98b.

It is limited in the horizontal direction by the second limit hole 96b. The clearance hole 96c provided in the center of the slider 96 is
A working pin 88a provided at the bottom of the support 88 is received. The play hole 96c is slightly larger than the working pin 88a,
Even if the working pin 88a draws an arc around the support shaft 90 in the drive range of the slider 9!3, it can be received in the play hole. The spring 100 is the slider 86
1 on the right (5 in Figure 2, this is the front; the same applies hereafter) Direction number 3 Keep tense.

That is, the tension of the spring 100 acts on the working pin 88a through the play hole 86e of the slider 86, and the support shaft 9
By generating a moment around 0, the transfer drum 3
8 is pressed toward the photosensitive drum 27. This pressing is the contact pressure of the recording paper against the photosensitive surface at the transfer position. Also, carriers mixed between the photosensitive surface and the recording paper during transfer are affected by the elasticity of Mylar 76 and the spring 100.
It is absorbed by the buffering effect of , protecting the photosensitive surface and mylar.

By the way, in the perspective view of FIG. 2 and the side view of FIG.
Please pay attention to 0.

In this embodiment, the clamper 78 is mounted near the wall so that the recording paper is tightly wrapped around the wall of the transfer drum. Therefore, the height of the clamper including the temporary spring 80 is higher than the wall surface, and there is a risk of contacting the photosensitive surface and damaging it. Therefore, a spacer 110 is provided to separate it from the photosensitive surface. The separation mechanism is the same as described above, and when the spacer 110 intervenes between the photosensitive drum 27 and the transfer drum 38 by one rotation, the transfer drum 38 is separated in an arc shape about the support shaft 90. The contact surface of the photoreceptor drum 27 that the spacer 110 comes into contact with is the bare surface of the drum body where the photoreceptor 28 does not exist, and there is no influence on the photoreceptor 28 . Further, as shown in the side view of FIG. 3a, both ends of the spacer 110 are tapered, so that the spacer 110 can be inserted and removed smoothly between the photosensitive drum 27 and the transfer drum 38 due to rotation of both. It is now possible to do this. Note that the spacer 110 sets the home mark for detecting the home position of the photoreceptor drum described above so that the spacer 110 can intervene even when the copying machine is stopped or on standby in order to avoid constant contact between the photoreceptor surface and Mylar. (hereinafter referred to as the stop position).

The position of the clamper is the transfer start position on the recording paper,
The transfer drum requires approximately one rotation from the stop position to the transfer position. On the other hand, since the photoreceptor drum rotates approximately 3/4 from the time it is cleaned to the time it is transferred,
When a copy execution command is input, the photosensitive drum 27 and the transfer drum 38 perform an idle rotation of about 90 degrees. FIG. 7 is a diagram showing the state of the transfer drum 38 at this time. This will be explained with reference to FIG. When a copy execution command is input at point A, idle rotation is performed by arrow a. The photosensitive surface is cleaned, charged, and erased between arrows a', and exposure starts at point B. The transfer drum clamps the recording paper at point C, but the photosensitive surface is being developed between arrows S and C. Transfer of the yellow toner image starts from point D1 and is performed between arrows d1. Since the photosensitive surface passes point B and starts the next exposure, magenta and cyan toner images are similarly transferred at points D2 + D3. During the cyan toner image transfer, at point E, the recording paper is separated from the transfer drum. It rotates further and reaches the stop position F.

Figure 3b is a side view of another embodiment of the invention. The basic mechanism in Figure 3b is the same as in Figure 3a, but
Mylar is separated from the photosensitive surface by energizing a solenoid. This will be explained with reference to FIG. 3b.

102 is a first link, and 104 is a second link.

The link is engaged with the drive shaft of the solenoid 106. 1
08 is a spring. The first link has a slider 96
A clearance hole similar to clearance hole 96c is provided to receive the first limit pin 96a.

One end of this first link is rotatably engaged with the slider guide 98, so when the solenoid 106 is energized, the drive shaft is retracted to the left in the figure and moves the slider 96 to the left via the link mechanism. Slide to . The clearance hole 96c of the slider 96 acts on the working pin 88a to apply a moment around the support shaft 90 to the support 88, and the wall surface of the mylar 76 of the transfer drum 38 is separated from the photosensitive surface of the photoreceptor 28. A control system (not shown) detects the home mark and controls the solenoid 106 to be energized or deenergized. In this embodiment, the separation may be achieved by deenergizing the solenoid. In this case, the positions of the spring 10''8 and the solenoid are reversed.

FIG. 4 shows an example of application of the present invention to a belt-shaped transfer body (hereinafter referred to as a transfer belt).

In FIG. 4, reference numeral 112 is a transfer belt made of a flexible dielectric material to which recording paper is attached and fixed, and is stretched by rollers 114a and 114b.

The rollers 114a, 114b and the transfer charger 40 are supported by a support mechanism (not shown), and the roller 1
It is rotatable around the rotation axis of 14a. roller 114
The bearing 116 of b is connected to the balance 120 via a spring 118.
is engaged with. The balance 120 is rotatable around a balance shaft 122, and a solenoid 12.6 is engaged with the other end via a link 124.

When transferring the toner image on the photosensitive surface, contact pressure between the photosensitive surface and the recording paper is required, so the solenoid 126 is energized and the balance 120 is at the position shown by the solid line in the figure.

The transfer belt 112 is tensioned by the spring 118 to be at the position shown by the solid line in the figure.

When the copying apparatus is stopped or on standby, the transfer surface of the transfer belt 112 is separated from the photosensitive surface.

Since the solenoid 126 is deenergized, the balance 120 is at the position of the virtual line, the tension of the spring 118 is released, and the transfer belt 112 is separated from the photosensitive surface by its own weight. The support structure 81 of the transfer belt 112 (not shown) has a limiter, so that it does not fall below the imaginary line in the figure.

Another example of the application of the present invention is spacing in which a flexible dielectric belt is pressed down by a spacer such as the one described above that protrudes from the circumferential surface of a photoreceptor drum. FIG. 5 shows this schematic structure. In this case, the spacer can be controlled to protrude and retract from the circumferential surface of the photoreceptor drum. For example, by using a transfer belt whose circumference is longer than the circumference of the photoreceptor belt, it is possible to cope with transfer to roll paper and repeat (simultaneous copying of multiple sheets) processing. In Figure 5, 12
8 is a solenoid, 130a and 130b are springs, and 132 is a spacer. The spacer 132 is held so as to be able to reciprocate in the diametrical direction of the side surface of the photoreceptor drum, and one end of the spacer 132 is fixed to the side surface of the photoreceptor drum by a spring 130a.
and 130b apply a centrifugal force. Further, the spacer 132 is coupled to a drive shaft of a solenoid 128 fixed to the side surface of the photoreceptor drum. When the solenoid 128 is energized by a control device (not shown), a centripetal force is applied to the spacer 132 and the spacer 132 is drawn inward from the circumferential surface of the photoreceptor drum 27. When the solenoid 128 is deenergized, the spring 132
It is pushed out by 0a and 130b and protrudes from the circumferential surface of the photosensitive drum 27. When the spacer 132 protrudes at the position where it contacts the transfer belt, the transfer belt is pushed down and separated from the photosensitive surface as shown by the imaginary line.

In the application example of the present invention shown in FIGS. 4 and 5, the developed toner images of the respective colors are first transferred to a transfer belt j- for color mixing, and then transferred to another transfer machine n (not shown). ) may be used as a transfer belt that transfers the image onto the recording paper. Even in this case, it is necessary to maintain a separation between the transfer belt and the photosensitive surface.
This separation can be achieved by exactly the same mechanism as described above.

■Effects of the Invention As described above, according to the present invention, the wall surface of the transfer body can be separated from the photosensitive surface when the color copying apparatus is stopped or on standby, so that unnecessary Early deterioration of the photoreceptor can be prevented without pressure contact. Further, if the present invention is applied to a portion of a clamper or the like having a convex portion, only that portion can be separated from the photosensitive surface, so that the photosensitive surface will not be damaged.

[Brief explanation of drawings]

FIG. 1 is a front view showing a schematic configuration of a color copying apparatus embodying one embodiment of the present invention. 2 is a perspective view showing the photosensitive drum and transfer drum of FIG. 1. FIG. Figures 3a and 3b are side views showing an embodiment of the present invention. FIG. 4 is a side view showing an application example of the present invention. FIG. 5 is a side view showing another example of application of the present invention. FIG. 6 is a sectional view showing a conventional clamp. 1 FIG. 7 is a timing diagram showing the operation of the transfer drum in FIG. 3a. lO: Holding plate 12: Contact glass 14:
Exposure lamp 15: Scanner 20: Lens 16, 18, 22, 24: Mirror 26:
Filter unit 27: Photoreceptor drum 28: Photoreceptor (charge carrier) 30
: Static neutralization charger 32: Static charger 34: Erase lamps 36Y, 36M, 36C: Developing device 38: Transfer drum (transfer body) 40: Transfer charger 42: Paper feed roller 44: Paper feed cassette 46: Registration roller 48.54 .56,5
8, 60, 68: Motor 50: Fixing device 52:
Copy tray 64: Precharger 66: Mylar static elimination charger 70: Support frame 72: Ring portion 74: Connecting portion 76: Mylar 78: Clamper 82, 84: Gear 88: Support body 90: Support shaft 94: Working pin 110.132 Ni spacer (protrusion) 106.126,128: Solenoid 112: Transfer belt (belt-shaped transfer body) Error 47 Child 5 figure Child 6 error 77

Claims (5)

[Claims] (1) Form electrostatic latent images on the photoconductor multiple times according to different color components of the original, and each time the electrostatic latent image according to each color component is formed, use a developer of the color corresponding to the color component. In a color copying machine that visualizes and transfers the developed image to a recording medium: A photoconductor and an object facing the photoconductor, such as a transfer drum or a transfer belt, are provided. A color copying apparatus characterized by being equipped with a separating means for relatively separating an object facing a photoreceptor. (2) The color copying apparatus according to claim 1, wherein the separating means is mounted so as to be movable forward and backward and is coupled to the forward and backward drive means. (3) The object facing the photoreceptor is a transfer drum, and the separation means is attached to the transfer drum and is located on the side of the outer peripheral surface of the transfer drum away from the surface that is used for visualization of the photoreceptor. A color copying apparatus according to scope (1). (4) The color copying apparatus according to claim (3), wherein the separating means is located at a position of a clamper that grips an edge of the recording medium. (5) The photoreceptor is located at a position where both edges of the circumferential surface of the photoreceptor drum are removed, and the separating means is located at a part of the both edges of the photoreceptor drum.
A color copying apparatus according to claim 1, wherein the color copying apparatus is mounted so as to be movable forward and backward and coupled to a forward and backward drive means.