JPS631325Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for cleaning the surface of a drum-shaped photoreceptor in a transfer type electronic copying machine having a wet developing device.

Conventionally, in a transfer type electronic copying machine having a wet type developing device that copies an image of one document once by rotating a drum-shaped photoreceptor twice, FIGS.
As shown in the figure, an elastic blade 2 is arranged reciprocally rotatably near a drum-shaped photoreceptor 1 that is rotated in the direction of the arrow, and is brought into pressure contact with the photoreceptor 1 only during cleaning. A cleaning device for removing developer remaining on the photoreceptor 1 is known.

However, in this cleaning device, the upper surface of the elastic blade 2 rises as it moves away from the contact area between the photoreceptor 1 and the elastic blade 2.
Since the developer 3 may accumulate between the upper surface of the elastic blade 2 and the photoconductor 1, the accumulated developer 3 may re-adhere to the photoconductor 1 after cleaning and adversely affect the image. When the elastic blade 2 is separated from the photoreceptor 1, the elastic blade 2 pulls the developer 3, which has the disadvantage that the next image will be smudged.

An object of the present invention is to provide a cleaning device that can eliminate the above-mentioned drawbacks.

The cleaning device of the present invention is characterized in that the edge of the elastic blade is released toward the upstream side in the rotational direction of the photoreceptor from the normal line of the pressure contact point of the elastic blade of the photoreceptor.

The present invention will be explained in detail below based on the embodiments shown in FIGS. 3 to 7.

In FIG. 3, reference numeral 4 indicates a drum-shaped photoreceptor, and this photoreceptor 4 is rotated in the direction of arrow a. Near the photoreceptor 4, in addition to a cleaning device 5 and a squeeze roller 6 that is rotated in the direction of arrow b to adjust the amount of developer on the photoreceptor 4, there is also a charging device, an exposure device, and a wet developing device (not shown). , a transfer device, etc. are arranged, and one copy is performed while the photoreceptor 4 rotates twice.

The cleaning device 5 is arranged between a wet developing device and a squeeze roller 6, which are arranged below the photoreceptor 4.

A rotation shaft 7 rotatably supported is disposed near the photoreceptor 4, and a blade holding member 8 is fixed to the rotation shaft 7. An elastic blade 9 is fixed to this blade holding member 8.

An actuating member 10 is fixed to one end of the rotating shaft 7, and a solenoid 11 is disposed on the photosensitive member 4 side of the actuating member 10. This solenoid 11 is fixed to a holding plate 12 of the electronic copying machine as shown in FIG. A connecting plate 13 is fixed to the plunger 11a of the solenoid 11, and a long hole 13a is formed at the tip of the connecting plate 13. A connecting pin 10a is protruded from the end of the actuating member 10 remote from the rotation axis 7, and this connecting pin 10a is connected to the elongated hole 13 of the connecting plate 13.
a, and the actuating member 10 is slidably connected to the plunger 11a by a predetermined distance.

A shaft 14 is fixed to the opposite side of the operating member 10 from the solenoid 11, and a stop member 15 for stopping the operating member 10 is provided on the shaft 14.
This stop member 15 is made of a flexible material and also has a cushioning effect. Pin 10b and shaft 14 of actuating member 10
A tension spring 16 is provided between the
This spring 16 connects the actuating member 10 to the plunger 11a.
It is biased in the direction away from the A locking protrusion 10 is provided on the side of the body of the actuating member 10 facing the stop member 15.
c is formed.

FIG. 3 shows a case in which current is supplied to the solenoid 11, and FIG. 4 shows a case in which no current is supplied to the solenoid 11.

When no current is supplied to the solenoid 11, the tension of the spring 16 causes the actuating member 1 to
The locking protrusion 10c of 0 is in contact with the stop member 15, and the elastic blade 9 is stopped at a constant distance from the photoreceptor 4.

When electric current is supplied to the solenoid 11, the plunger 11a moves in a direction away from the stop member 15 by a predetermined distance and rotates the actuating member 10, thereby rotating the rotating shaft 7 integrated therewith. The elastic blade 9 rotates along with the moving shaft 7 and comes into pressure contact with the photoreceptor 4. The elastic blade 9 is attached to the photoreceptor 4
The surface of the photoreceptor 4 is cleaned by scraping off the developer from the surface of the photoreceptor 4 while in pressure contact with the photoreceptor 4.

Next, when the supply of current to the solenoid 11 is stopped, the plunger 11a moves by a certain distance in the direction of the stop member 15, and the plunger 11a
The operating member 10 is rotated in the direction of the stop member 15 by the pressing force of the spring 16, the tensile force of the spring 16, and the rotational force due to the weight of the blade holding member 8 and the elastic blade 9.
As the actuating member 10 rotates, the elastic blade 9 rotates in a direction away from the photoreceptor 4. When the locking protrusion 10c of the actuating member 10 comes into contact with the stop member 15, the actuating member 10 stops, and the rotating shaft 7 stops accordingly, so that the elastic blade 9 is separated from the photoreceptor 4 by a certain distance. and stop. When the elastic blade 9 slowly separates from the photoreceptor 4, the tip of the elastic blade 9 pulls the developer, causing liquid flow stains on the image. In order to prevent this staining, the tensile force of the spring 16 must be above a certain level. However, if the tensile force of the spring 16 is too strong, the force with which the operating member 10 collides with the stop member 15 is too large, so the tensile force of the spring 16 must be below a certain level. Therefore, the tensile force of the spring 16 needs to be adjusted within a predetermined range. The plunger 11a is connected to the actuating member 10 through the elongated hole 13a, so when the elastic blade 9 is rotated in a direction away from the photoreceptor 4, the plunger 11a moves by a certain distance to maintain a constant speed. Operating member 10
, the initial velocity at which the elastic blade 9 leaves the photoreceptor 4 can be made sufficiently large. Further, it is desirable that the elastic blade 9 is stopped at a position separated from the photoreceptor 4 by a sufficient distance.

When the actuating member 10 collides with the stop member 15, the spring 16 moves the actuating member 10 toward the stop member 15.
Since it is energized, the actuating member 10 hardly vibrates. Further, since the stop member 15 has a buffering effect, it reduces the collision force of the actuating member 10 and prevents the actuating member 10 from vibrating. Furthermore, although the plunger 11a vibrates when it stops, the vibration of the plunger 11a is not transmitted to the operating member 10 because the operating member 10 is slidably connected to the plunger 11a. Note that the stop member 15 may be made of a hard material, and the locking protrusion 10c of the actuating member 10 may be provided with a buffer member.

The elastic blade 9, as shown in FIG.
When pressed against the photoreceptor 4, the upper surface 9a of the elastic blade 9 is lowered as it moves away from the contact area between the photoreceptor 4 and the elastic blade 9. In other words, the upper surface 9a of the elastic blade 9 As it moves away from the base, it tilts downward by a predetermined tilt angle θ.

Further, the upper surface 9a of the elastic blade 9 is
As shown in the figure, the upper surface 9a of the elastic blade 9 is formed into a slope that descends from the contact area between the photoreceptor 4 and the elastic blade 9 as the distance from the photoreceptor 4 increases.
may be configured to be inclined downward by a predetermined inclination angle θ as the distance from the photoreceptor 4 increases with respect to the horizontal line A.

In the cleaning device of the present invention, when the elastic blade is pressed against the photoreceptor, the upper surface of the elastic blade is lowered as it moves away from the contact area between the elastic blade and the photoreceptor. Since the developer does not accumulate between the photoconductor and the photoreceptor, the developer does not adhere to the photoconductor again after cleaning, and the elastic blade does not pull the developer when separating the elastic blade from the photoconductor. There are no stains on the image.

[Brief explanation of drawings]

1 and 2 are front views showing the main parts of a conventional cleaning device, FIGS. 3 and 4 are front views showing the cleaning device of the present invention, and FIG. 5 is a slope showing the main parts of the same device. FIG. 6 is a front view showing the main parts of the same device, and FIG. 7 is a front view showing the main parts of another embodiment of the present invention. 4... Photoreceptor, 7... Rotating shaft, 9... Elastic blade, 10... Operating member, 11... Solenoid,
11a... Plunger, 15... Stopping member, 16
...Spring.

Claims (1)

[Utility Model Claims] 1. A cleaning device for removing developing solution on a photoconductor of a transfer type electronic copier, characterized in that the edge of the elastic blade is released toward the upstream side of the rotation direction of the photoconductor from the normal line at the pressure contact point of the elastic blade of the photoconductor. 2. The cleaning device according to claim 1, characterized in that the rotating shaft that holds the elastic blade is disposed downstream of the normal line in the rotation direction.