JPH0566701A - Cleaning device of electrophotographic copying machine for wet processing - Google Patents

Abstract

PURPOSE:To provide the cleaning device of the electrophotographic copying machine for wet processing which prevents the liquid dropping from a cleaning blade parted from a photosensitive drum from sticking onto a transfer paper transportation guiding plate and staining the transfer paper. CONSTITUTION:A developer is supplied by driving of a main motor to a developing unit and a cleaning unit 1. The cleaning unit has a cleaning roller 3 which comes into contact with the photosensitive drum 2, a distribution plate 4 which is turnable between a supply position for supplying the developer to the cleaning roller 3 and a stop position for stopping the supply, and the cleaning blade 5 which is provided attachably and detachably to and from the photosensitive drum 2 and is parted from the photosensitive drum 2 after the end of a copying stage. The distribution plate is turned to the stop position before the start of the final copying stage of a continuous copying mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device in a wet electrophotographic copying machine.

[0002]

2. Description of the Related Art An outline of a conventional wet electrophotographic copying machine to which the cleaning device of the present invention is applied as described above is shown in FIG. Is erased, and the erase 12 removes the charge potential of the non-image portion. Then, the original document illuminated by a halogen lamp (not shown) is projected onto the photosensitive drum 2 by the optical system, and an electrostatic latent image is obtained by the intensity of the light. Toner electrostatically charged by the developing roller 14 of the developing unit 13 adheres to the electrostatic latent image to form a visible image. Since a large amount of toner adheres to the photosensitive drum 2 that has passed through the developing roller 14, the squeeze roller 15 squeezes off excess toner. The transfer paper 17 is transferred to the photosensitive drum 2 by the registration roller 16.
The transfer charger 18 is supplied from the back side of the transfer paper 17.
Transfer is performed by giving a positive charge by. Then, the toner remaining on the photosensitive drum 2 is removed by the cleaning unit 1, and the residual charge is erased by the discharging lamp 19.

Since most of the cleaning unit 1 is similar to the embodiment of the present invention shown in FIG. 1, it will be described with reference to this. By driving a main motor (not shown), the developing solution is transferred to the developing unit 13,
The cleaning unit 1 is supplied to the cleaning unit 1, and the cleaning unit 1 is rotatable between a cleaning roller 3 that contacts the photosensitive drum 2 and a supply position for supplying the developing solution to the cleaning roller 3 and a stop position for stopping the supply. And a cleaning blade 5 that is provided so as to be able to come into contact with and separate from the photosensitive drum 2, and that is separated from the photosensitive drum 2 after the copying process is completed. In addition, 7 is a developer distribution solenoid, 8 is a cleaning solenoid, and 9
Indicates a scraper, and 10 indicates a squeeze shaft.

[0004]

FIG. 5 shows a timing chart of the above-mentioned thing. A main switch (not shown) is turned on to start driving the main motor, and 5 seconds later, the cleaning solenoid 8 is turned on. Then, the cleaning roller 3 and the cleaning blade 5 come into contact with the photosensitive drum 2, and the main motor stops when idling ends. When a start key (not shown) is turned on, the main motor restarts driving, and the developing solution and the cleaning solution are supplied from the developing solution tank (not shown). A registration clutch (not shown) that controls the rotation of the registration roller 16 is turned off after supplying the final sheet, and 0.6 seconds after that, the developer distribution solenoid 7 is turned on, and the distribution plate 4 is rotated counterclockwise as shown by an arrow. It rotates in the direction and moves to the stop position, and the supply of the cleaning liquid to the cleaning roller 3 is stopped. In this way, after the developer distribution solenoid 7 is turned on and the supply of the cleaning solution is stopped,
After 6 seconds, the cleaning solenoid 8 is turned off for 0.3 seconds, the cleaning blade 5 is separated from the photosensitive drum 2,
Then, by turning on again, the cleaning blade 5 comes into contact with the photosensitive drum 2 and the cleaning blade 5
The foreign matter adhering to the tip of the photosensitive drum 2 is removed by the impact force at the time of contact with the photosensitive drum 2. Further, 4.1 seconds later, the developer distribution solenoid 7 is turned off, the distribution plate 4 rotates clockwise and moves to the supply position,
The supply of the cleaning liquid to the cleaning roller 3 is restarted. By the way, as described above, after the developer distribution solenoid 7 is turned on to move the distribution plate 4 to the stop position,
The time until the cleaning blade 8 is separated from the photosensitive drum 2 after the cleaning solenoid 8 is turned off is 0.
Since it is as short as 6 seconds, a large amount of liquid adheres to the cleaning blade 5, and when the cleaning solenoid 8 is turned off, that is, when the cleaning solenoid 8 is separated from the photosensitive drum 2, the liquid drops from the tip of the cleaning blade 5, and this dropped liquid Is attached to the transfer paper conveyance guide plate to stain the transfer paper.

Therefore, an object of the present invention is to solve the problems of the conventional cleaning device as described above, and the liquid is dropped from the tip of the cleaning blade separated from the photosensitive drum, and the dropped liquid is the transfer paper. Another object of the present invention is to provide a cleaning device that does not adhere to the transport guide plate and stain the transfer paper.

[0005]

In order to achieve the above-mentioned object, the present invention drives a main motor to supply a developing solution to a developing unit and a cleaning unit, and the cleaning unit is cleaned. A roller, a distribution plate rotatably provided between a supply position for supplying the developing solution to the cleaning roller and a stop position for stopping the supply of the developing solution, and a cleaning blade provided so as to come in contact with and separate from the photosensitive drum. In an electrophotographic copying machine that has a cleaning roller and a cleaning blade separated from the photosensitive drum by the time the main motor stops after the copying process, at least before the start of the final copying process in the continuous copying mode. In addition, the distribution plate should be rotated to the stop position to stop the liquid supply to the cleaning roller. It is an butterfly. In the 1-copy mode, the distribution plate is set to the supply position from the start of the main motor drive to the start of the copying process, and when the copying process starts, the distribution plate is rotated to the stop position to the cleaning roller. Stop the supply of liquid. The distribution plate is rotated to the stop position to stop the supply of the developing solution a predetermined time before the end of the copying process.

[0006]

In the above-mentioned cleaning device, in the continuous copying mode, the distribution plate is moved to the stop position after the feeding of the transfer sheet one sheet before the final sheet is finished, and the main motor is stopped after the copying process is finished. In the meantime, the cleaning roller and the cleaning blade are separated from the photosensitive drum. Further, in the one-copy mode, the distribution plate is placed in the supply position from the start of the driving of the main motor to the start of the copying process, and then the distribution plate is rotated to the stop position.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiments of the present invention shown in the drawings, the same parts as those of the conventional one are designated by the same reference numerals, and the description thereof will be omitted. Figure 2
Shows a time chart in the continuous copying mode in this embodiment, which is 0.6 when the resist clutch is turned off after the supply of at least one transfer sheet before the final sheet is completed.
For a second, the developer distribution solenoid 7 is turned off and the distribution plate 4 is placed at the supply position. After that, the developer distribution solenoid 7 is turned on to move the distribution plate 4 to the stop position, and then the registration clutch is turned on and the final position is reached. After 1.2 seconds from the end of supplying the transfer paper and turning it off, the cleaning solenoid 8 is turned off and the cleaning blade 5 is separated from the photosensitive drum 2 in the same manner as in the conventional one. Figure 3
Shows a time chart in the single copy mode in this embodiment. The developer distribution solenoid 7 is turned off and the distribution plate 4 is supplied for 2 seconds after the start key is turned on and the main motor starts driving. Then, the developer distribution solenoid 7 is turned on to move the distribution plate 4 to the stop position,
Then, after a considerable amount of time has passed, the cleaning solenoid 8 is turned off and the cleaning blade 5 is separated from the photosensitive drum 2 in the same manner as described above. In this way, in both the continuous and single copy modes, the distribution plate 4 is moved to the stop position and the liquid is supplied to the cleaning roller 3 long before the cleaning blade 5 is separated from the photosensitive drum 2. Therefore, the amount of the liquid adhering to the cleaning roller 3, that is, the amount of the liquid adhering to the cleaning blade 5 is reduced, and the liquid does not drop from the tip.

[0008]

As described above, according to the present invention, the developing solution is supplied to the developing unit and the cleaning unit by driving the main motor, and the cleaning unit stops the supplying position and the supplying position of the developing solution to the cleaning roller. The distribution plate rotatably provided between the main motor and the stop position after the copying process is completed. , The cleaning roller and the cleaning blade are separated from the photosensitive drum, the distribution plate is rotated to the stop position at least before the start of the final copying process in the continuous copying mode, and the main motor is driven in the single copy mode. From the start of the copying process to the start of the copying process, place the distribution plate at the supply position and start the copying process. By rotating the plate to the stop position, the cleaning blade separates from the photosensitive drum much faster than the conventional cleaning device in any case, and the liquid supply to the cleaning roller is stopped. Since the amount of the liquid adhering to the cleaning roller at the time of the separation is small, that is, the amount of the liquid adhering to the cleaning blade is small, the liquid does not drop from the tip of the cleaning blade. There is an effect that it does not adhere to the transfer guide plate and stain the transfer paper.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a time chart in the same continuous copying mode.

FIG. 3 is a time chart in the same single copy mode.

FIG. 4 is a schematic diagram of a wet electrophotographic copying machine to which the cleaning device of the present invention is applied.

FIG. 5 is a time chart of a conventional cleaning device.

[Explanation of symbols]

 1 Cleaning Unit 2 Photosensitive Drum 3 Cleaning Roller 4 Distribution Plate 5 Cleaning Blade 7 Developer Distribution Solenoid 8 Cleaning Solenoid 13 Development Unit 16 Registration Roller

Claims (3)

[Claims] 1. A main motor is driven to supply a developing solution to a developing unit and a cleaning unit, and the cleaning unit includes a cleaning roller and a cleaning roller.
The cleaning roller includes a distribution plate rotatably provided between a supply position for supplying the developer and a stop position for stopping the supply of the developer, and a cleaning blade provided so as to come in contact with and separate from the photosensitive drum. In an electrophotographic copying machine in which the cleaning roller and the cleaning blade are separated from the photosensitive drum before the main motor is stopped after the copying process is completed, the distribution is performed at least before the start of the final copying process in the continuous copying mode. A cleaning device characterized by rotating the plate to a stop position to stop the supply of the liquid to the cleaning roller. 2. In the single copy mode, the distribution plate is set to the supply position from the start of the main motor drive to the start of the copying process, and the distribution plate is rotated to the stop position when the copying process starts. The cleaning device according to claim 1, wherein the supply of the liquid to the cleaning roller is stopped. 3. The cleaning device according to claim 1, wherein the supply of liquid is stopped by rotating the distribution plate to a stop position a predetermined time before the end of the copying process.