JPH05303288A - Image forming mechanism - Google Patents

Abstract

PURPOSE:To reduce the number of the units of a full color copying machine, and to improve functionality, as well. CONSTITUTION:An intermediate transfer body cleaning device 31 and a transfer device 27 transferring a toner image from an intermediate transfer body 10 onto a form, are integrated into one body. As conditions for the integration, the length of the intermediate transfer body 10 is set total length or more, of the length of the longest form and a distance from the cleaning device 31 to the transfer device 27, so that both of them can be simultaneously, turned on/off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming mechanism such as a full color copying machine having an intermediate transfer member.

[0002]

2. Description of the Related Art Conventionally, in this type of image forming mechanism, a cleaning device for cleaning residual toner on an intermediate transfer member and a transfer device for transferring a toner image from the intermediate transfer member to a transfer paper are different units. And it was operating at individual timing.

That is, in the case of a full-color copying machine, since the intermediate transfer member is rotated a plurality of times (usually three rotations) and then transferred to the paper, the second transfer device and the intermediate transfer member for transferring from the intermediate transfer member to the paper during that time. Cleaning device can not be driven.

Moreover, if the cleaning device is also driven at the same time as the driving of the second transfer device, the toner image at the end of the image that has not been transferred to the paper is also removed, so that it has to be operated at different timings.

That is, the timing of turning on both of them is such that the transfer device first turns on at the position of the leading edge of the image on the intermediate transfer member to perform transfer, and then the position of the leading edge of the image reaches the position of the cleaning device. The cleaning device was turned on.

[0006]

However, in general,
An image forming mechanism having an intermediate transfer member has a larger number of parts than other image forming mechanisms, resulting in an increase in cost. In addition, since there are many units, the machine becomes complicated, the possibility of failure increases, and the maintenance service becomes complicated.

In view of the above, an object of the present invention is to reduce the number of units and improve the functionality thereof in an image forming mechanism such as a full color copying machine.

[0008]

A means for solving the problems according to claim 1 of the present invention is for cleaning the toner remaining on the intermediate transfer member 10 with a cleaning device 31 and for transferring the toner image from the intermediate transfer member 10 to the transfer paper 19. Transfer device 27
And are integrated.

According to a second aspect of the present invention, the peripheral length of the intermediate transfer member 10 is defined by the length of the longest transferable paper 19 for image formation and the length from the transfer device 27 to the intermediate transfer member cleaning device 31. The cleaning device 31 and the transfer device 27 are turned on / off at the same timing.
That is, it was turned off.

[0010]

In the above means for solving the problems, the transfer device 27 and the intermediate transfer member cleaning device 31 are turned on / off at a timing (within 200 msec) immediately before the tip of the toner image on the intermediate transfer member 10 comes onto the transfer roller 22. Turn on.

Then, the transfer roller 22 contacts the intermediate transfer member 10, and the blade 32 also contacts the intermediate transfer member 10. At this time, even if the A3 size toner image is visualized on the intermediate transfer body 10, the peripheral edge of the intermediate transfer body 10 is long, and therefore the trailing edge of the image is located in front of the blade 32. , The toner image is not removed.
Therefore, the transfer roller 22 and the cleaning blade 32 can be turned on at the same time.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an intermediate transfer member showing an embodiment of an image forming mechanism according to the present invention, FIG. 2 is a general block diagram of the image forming mechanism, and FIG. 3 is a state in which a transfer cleaning unit is OFF. Fig. 4 shows the O of the transfer cleaning unit.
It is a figure which shows the state at the time of N.

First, a basic structure and a basic operation of a color copying machine as an example of an image forming mechanism according to an embodiment of the present invention will be described with reference to FIG.

This color copying machine, as shown in FIG.
A transparent document placing table 1 is provided on the upper surface of the machine frame. An exposure optical system 2 is arranged below the original placing table 1, and the exposure optical system 2 includes a light source lamp 2a for irradiating the original 13 placed on the original placing table 1 with light. A plurality of reflecting mirrors 2b for guiding the reflected light from the original 13 onto the photoconductor 7 as shown by a chain line, an imaging lens 2c arranged on the optical path, and three primary colors of red, green, and blue. The color separation filter 2d having the color filter of

On the optical axis of the above-mentioned exposure optical system 2, a belt-shaped photoconductor 7 made of an organic photoconductor (OPC) to which a light image subjected to exposure scanning is irradiated is arranged. This photoconductor 7
Paper feed cassettes 8 and 9 accommodating a transfer paper 19 are disposed on the paper input direction side of. Each of these paper feed cassettes 8,
Paper feed rollers 23 and 24 are provided on the upper surface of the transfer paper 9 and the paper feed rollers 23 and 24, respectively.
9 is discharged from the paper feed cassettes 8 and 9 and is sent toward the intermediate transfer body 10.

A timing roller 25 is provided on the delivery side of the paper feed rollers 23 and 24 in the direction of the intermediate transfer body 10. The timing roller 25 rotates in synchronization with the intermediate transfer body 10. It is being done.

The intermediate transfer member 10 includes first to third rollers 18
It is driven to rotate by a, 18b, and 18c, and is in pressure contact with a driving roller 15 that rotationally drives the photoconductor 7. On the back surface side of the intermediate transfer body 10 at the portion where the drive roller 15 is pressed, the transfer charge 2
1 is arranged to configure the first transfer device 20.

On the other hand, a transfer roller 22 is disposed on the surface side of the intermediate transfer member 10 at the position where the third roller 18c is disposed, and a second transfer device 27 is formed. A peeling plate 28, a conveying belt 29, and a fixing device 30 are arranged in this order on the delivery side of the transfer roller 22.

The photoconductor 7 irradiated with the reflected light from the exposure optical system 2 is driven to rotate by the driven roller 14 and the driving roller 15.

A charging charger 16 for charging the photoconductor 7 and a discharge lamp 26 for discharging the photoconductor 7 are provided on the outer periphery of the photoconductor 7 on the side of the driven roller 14.

A cleaning device 17, which is a cleaning means for removing toner remaining on the photoconductor 7, is disposed below the photoconductor 7 in the vicinity of the charging charger 16. The cleaning device 17 is provided with a cleaning blade 17a made of urethane or the like. These cleaning blades 17a are pressed against the photoconductor 7 to scrape off, for example, toner remaining on the photoconductor 7.

In the vicinity of the central portion above the photoconductor 7, a black and white developing tank 3 which is not in contact with the photoconductor 7 is provided.
Color developing tanks 4 to 6 are provided, and yellow, magenta, and cyan color developers are individually stored in the color developing tanks 4 to 6.

Next, the operation of the color copying machine having the above construction will be described. First, the copy mode is executed by pressing a copy start switch (not shown). This copy mode has a copy cycle in which yellow, magenta, and cyan are developed and transferred to the intermediate transfer body 10. When the copy mode is executed, first, the yellow copy cycle is executed. become.

That is, the original 1 placed on the original table 1
3 is irradiated with light from the light source lamp 2a, and exposure scanning is performed. The reflected light from the original 13 is incident on the color separation filter 2d via the reflecting mirrors 2b ... And the imaging lens 2c, and is separated into color components by the color separation filter 2d.

The light for each color component transmitted through each color filter of the color separation filter 2d by the above-mentioned exposure scanning is irradiated onto the photoconductor 7 which is uniformly charged by the charging charger 16, and the photoconductor 7 is at the portion A. Exposed. As a result, the photoconductor 7
A yellow electrostatic latent image corresponding to the image of the original 13 is formed. After that, the above electrostatic latent images are separated into the color separation filters 2d.
In the facing portion of the developing tank 4 having the yellow developer which is the complementary color of the above, it is developed with the developer supplied from the developing magnet roller and is visualized to form a toner image. Then, this toner image is transferred to the intermediate transfer member 10 by the transfer charger 21.

Upon completion of the yellow copying cycle, the photoconductor 7 is cleaned by the cleaning device 17 and discharged by the discharge lamp 26. And
The magenta and cyan toner images are transferred to the intermediate transfer member 10 in the same copy cycle as described above.

When each of the above copy cycles is executed,
The toner image for each color component is transferred to the same position of the intermediate transfer member 10 by the transfer charger 21, and the toner for each color component is overlaid to form one completed toner image.

On the other hand, the transfer papers 19 accommodated in the paper feed cassettes 8 and 9 are fed one by one to the timing roller 25 by the paper feed rollers 23 and 24, and the timing roller 25 is fed.
Conveys the transfer paper 19 between the intermediate transfer body 10 and the transfer roller 22 in synchronization with the intermediate transfer body 10.

The transferred transfer paper 19 is transferred to the transfer roller 22.
After the toner image on the intermediate transfer body 10 is transferred by, the toner image is separated from the intermediate transfer body 10 by the peeling plate, and introduced into the fixing device 12 by the conveyor belt 11. Then, after the color toner image is fixed on the transfer paper 23 and then discharged to the outside, the one-time copy mode ends.

In the copying machine having the above-described structure and operation, in this embodiment, the transfer roller 22 portion is formed by integrating the second transfer device 27 and the intermediate transfer member cleaning device 31 as shown in FIG. Transfer / cleaning unit 33
And both are turned on / off at the same timing. The peripheral length of the intermediate transfer body 10 at this time is the length of the longest copy paper (A3) that can be copied by this machine and the transfer roller 22 to the intermediate transfer body cleaning blade 32.
The distance to and more than the sum.

Specific configurations of the second transfer device 27 and the intermediate transfer cleaning device 31 of the transfer / cleaning unit 33 will be described with reference to FIGS. 1, 3 and 4.

As shown in FIGS. 3 and 4, the second transfer device 27 includes a transfer / cleaning unit 33, and a transfer roller 22 disposed between the transfer roller 22 and a roller 18c located inside the intermediate transfer member 10. An L-shaped arm 36 is supported by the unit main body 33a via a shaft 35 so as to be in contact with or separated from the transfer body 10, and a swing means 37 for swinging the arm 36.

The swinging means 37 includes an eccentric cam 39 which is driven to rotate about a shaft 38 by a motor, a swinging lever 41 which abuts on the cam 39 and swings around a shaft 40, and the swinging lever 37. The tension spring 42 is provided between the tip of the arm 41 and the right end of the arm 36.

On the other hand, the intermediate transfer member cleaning device 3
1 includes a blade support portion 44 extending from the arm 36 along the intermediate transfer member 10, and the cleaning blade 32 fixed to the tip of the blade support portion 44.

The second transfer device 27 and the intermediate transfer member cleaning device 31 are integrated by a transfer cleaning unit 33 and are detachable from the front surface of the copying machine. In FIGS. 3 and 4, reference numeral 45 is a toner receiver.

Next, the operation of the transfer cleaning unit 33 will be described with reference to FIGS. ON / OFF of the second transfer device 27 and the intermediate transfer member cleaning device 31
Is turned on immediately before the leading edge of the toner image on the intermediate transfer member 10 comes onto the transfer roller 22 (within 200 msec).

Then, the eccentric cam 39 rotates and the swing lever 41 swings clockwise about the shaft 40, so that the right end of the arm 36 is pulled downward by the spring 42, and the arm 36 moves clockwise around the shaft 35. Rotate in the direction. Therefore, the transfer roller 22 comes into pressure contact with the roller 18c via the intermediate transfer body 10.

On the other hand, by swinging the arm 36, the blade supporting portion 44 integrated with the arm 36 also approaches the intermediate transfer body 10 as shown in FIG. 4, and the blade 32 also contacts the intermediate transfer body 10. At this time, even if the toner image of A3 is visualized on the intermediate transfer body 10, since the peripheral length of the intermediate transfer body 10 is long, the trailing edge of the image is located in front of the blade 32. Then, the transfer paper 19 is conveyed and transferred by the transfer roller 22.

After that, the residual toner remaining on the intermediate transfer member 10 is cleaned by the cleaning blade 32 which is turned on at the same time, and is turned off within 400 msec after the position of the trailing edge of the image reaches the position of the cleaning blade 32.

By performing the above operation, the second transfer device 27 and the cleaning device 31 can be integrated, the number of parts can be reduced, and the cost can be reduced.

The present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

[0042]

As is apparent from the above description, claim 1
According to the invention, since the transfer device and the cleaning device are integrated, it is effective in solving the problem of a large number of parts, which is a problem in a copying machine having an intermediate transfer member, and it is possible to reduce the number of parts. Therefore, the cost can be reduced.

Further, according to the invention of claim 2, the circumference of the intermediate transfer member is equal to or more than the sum of the length of the longest transfer paper capable of forming an image and the length from the transfer device to the intermediate transfer member cleaning device. Therefore, the cleaning device and the transfer device can be turned on at the same timing, the number of operations of the unit can be reduced, and the occurrence of troubles can be reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an intermediate transfer member section showing an embodiment of an image forming mechanism according to the present invention.

FIG. 2 is an overall configuration diagram of an image forming mechanism.

FIG. 3 is a diagram showing a state in which a transfer cleaning unit is OFF.

FIG. 4 is a diagram showing a state in which a transfer cleaning unit is ON.

[Explanation of symbols]

 3,4,5,6 developing tank 7 photoconductor 10 intermediate transfer member 22 transfer roller 27 second transfer device 31 intermediate transfer member cleaning device 32 cleaning blade 33 transfer / cleaning unit 36 arm 37 swinging means 39 eccentric cam 41 swinging Lever 42 Tension spring 44 Blade support

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuhiro Nagayama 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation

Claims (2)

[Claims] 1. An image forming mechanism having an intermediate transfer member, comprising: a cleaning device for cleaning residual toner on the intermediate transfer member; and a transfer device for transferring a toner image from the intermediate transfer member to a transfer paper. An image forming mechanism in which a transfer device and the cleaning device are integrated to form a transfer / cleaning unit. 2. The peripheral length of the intermediate transfer member according to claim 1, which is equal to or greater than the sum of the length of the longest transferable image forming paper and the length from the transfer device to the intermediate transfer member cleaning device. An image forming mechanism characterized in that the cleaning device and the transfer device are configured to be turned on / off at the same timing.