JPH0552496B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Subject of the Invention] The present invention relates to a cleaning mechanism for an electrophotographic copying machine, and relates to a cleaning mechanism suitable for reliably removing residual toner adhering to the surface of a photoreceptor drum without damaging the photoreceptor drum. Regarding the mechanism.

[Background of the invention]

Conventionally, various types of cleaning mechanisms using blades have been proposed for electrophotographic copying machines. For example, as shown in FIG. 1, the tip of a resilient blade 1 is pressed against the photoreceptor drum 2 in a direction opposite to the rotating direction of the photoreceptor drum 2, and the toner 3 remaining on the photoreceptor drum 2 is removed. What is called the counter blade cleaning method, which scrapes with the tip of blade 1.
Alternatively, as shown in FIG. 2, the tip of an elastic blade 1 is pressed against the photoreceptor drum 2 in the same direction as the rotation direction of the photoreceptor drum 2, and the toner 3 remaining on the photoreceptor drum 2 is scraped off. What is called the trailing blade cleaning method,
Furthermore, there are intermediate ones shown in FIGS. 3 and 4.

In all of the above, the blade 1 is always in pressure contact with the photoreceptor drum 2 in the same or opposite direction to the rotating direction of the drum, and when the power is turned off, the blade 1 is moved from the photoreceptor drum 2 by means such as a solenoid.
However, when the blade 1 is pressed in such a direction, although a cleaning effect can be expected, there is a drawback that the surface of the photoreceptor drum is likely to be damaged. That is, as shown in FIG. 5, in the conventional holding means for the blade 1, the position of the holder 4 is fixed, and the holder 4 rotates at most about one point in parallel to the photoreceptor drum axis. Regardless of the state of sliding contact between the photosensitive drum 2 and the blade 1, the blade 1 is pressed against the surface of the photosensitive drum 2 with the same pressure. Therefore, depending on the setting condition of the blade 1, the surface of the photoreceptor drum 2 may be damaged, and after many years of use, parts of the blade 1 that do not come into contact with the surface of the photoreceptor drum 2 may appear, causing damage to the photoreceptor drum. There are drawbacks such as the residual toner of No. 2 solidifying.

[Purpose of the invention]

The present invention has been made in view of the above points, and an object of the present invention is to provide a cleaning mechanism that reliably removes residual toner adhering to the surface of a photoreceptor drum and does not damage the surface of the photoreceptor drum. do.

[Summary of the invention]

The gist of the present invention is to achieve the above-mentioned objects.
A holding member that holds the blade is made to be able to rotate in the horizontal direction, and both ends of the holding member are made to be independently movable in the front and rear directions so as to absorb all of the force of the photoreceptor drum either in the vertical or longitudinal direction or in the diagonal direction. , the tip of the blade is always in contact with the surface of the photoreceptor drum with uniform pressure.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described based on the drawings.

6 is a side view of a cleaning mechanism constituting an embodiment of the present invention, FIGS. 7a and 7b are perspective views for explaining the present invention, and FIG. 7a is a photosensitive drum 11 and a blade. 18 relationships, and the 7th
Figure b is a perspective view of the blade 18 seen from the opposite direction to Figure 7a. FIG. 8 is a plan view with a part of the frame omitted. In the figure, a paper feed guide 12 and a cleaning mechanism 1 are located around the photoreceptor drum 11.
3, a charger 14, a transfer corona discharger 15, etc. are arranged, and the photosensitive drum 1 is placed on the copy paper 17 fed from the registration roller through the paper feed guide 12
The visible toner image formed on 1 is transferred by a transfer corona discharger 15 and sent through a roller 16 to a fixing device (not shown). There is no problem if all the toner in the visible toner image formed on the surface of the photoreceptor drum 11 is transferred to the copy paper 17 during transfer, but in reality, toner remains on the photoreceptor drum 11. This residual toner is removed by a cleaning mechanism 13.

The cleaning mechanism 13 includes a blade 18 whose tip is in contact with the surface of the photoreceptor drum 11, a holding member 19 that holds the blade 18, and a holding member 19.
The blade 18, the holding member 19, the supporting member 20, and a frame 21 that enclose the blade 18, the holding member 19, the supporting member 20, and the like. blade 18
is synthetic rubber such as urethane, nitrile, silicone, etc.
Alternatively, it is an elastic plate-like body made of natural rubber, the tip of which is in contact with the surface of the photoreceptor drum 11,
The rear end is adhesively fixed to the front part of a holding member 19 made of a plate-like member using an adhesive or the like. The support member 20 is also made of a plate-like member, and is pivotally connected to the holding member 19 at the center by a screw 22 so as to be freely rotatable. Engagement pieces 20a and 20b are integrally formed with the support member 20 at the rear end side thereof with a notch, and
The tip of a guide 23 that engages with the engagement pieces 20a, 20b and guides the support member 20 is fitted into the notch formed by the engagement pieces 20a, 20b and the support member 20, and the support member 20 is guided in the front-rear direction while supporting its both ends. The shape of the guide 23 is such that the side surface is bent into a dogleg shape, and the supporting members 26, 27
It is supported so that it can rotate clockwise or counterclockwise around the center, and the tip fits into the notch formed by the engaging pieces 20a, 20b and the support member 20 as described above, and the rear end has two protrusions 23a, 23
b is provided. The other ends of springs 24 and 25, which have one end engaged with the projections 21a and 21b of the frame body 21, are engaged with the projections 23a and 23b.

With the above configuration, if the axis of the photoreceptor drum 11 is shifted as shown by the dotted line in FIG. 8 for some reason, the supporting member 2
0 rotates clockwise around the screw 22 as shown by arrow A, and rotates as shown by arrows B and C against or due to the elasticity of springs 24 and 25 that bias the guide 23. Move back and forth. In other words, even if the central axis of the photoreceptor drum 11 is shifted up and down, back and forth, or diagonally, the support member 20
is moved back and forth or diagonally by the guide 23, and the holding member 19 is rotated clockwise or counterclockwise about the screw 22.
Therefore, the holding member 19 is attached to the front end of the supporting member 20.
The entire surface of the tip of the blade 18 fixed thereon is always in contact with the surface of the photoreceptor drum 11 evenly and with a constant pressure.
The toner remaining on the photosensitive drum 11 is reliably removed, and there is no fear that the surface of the photosensitive drum 11 will be scratched.

〔Effect of the invention〕

As explained above, the cleaning mechanism according to the present invention allows the holding member that holds the blade to rotate in the horizontal direction, and also allows both ends of the holding member to independently move in the front and back direction. The tip of the blade always contacts the surface of the photoreceptor drum with uniform pressure, which absorbs all the displacement of the photoreceptor drum in the vertical and longitudinal directions or in the diagonal direction. It has an extremely excellent effect of being able to be removed without damaging the surface.

[Brief explanation of the drawing]

1 to 4 are diagrams showing a schematic configuration of a conventional cleaning mechanism, FIG. 5 is a diagram showing a contact state between a photosensitive drum and a blade of a conventional cleaning mechanism, and FIG. 6 is an embodiment of the present invention. 7a and 7b are perspective views for explaining the present invention. FIG. 8 is a partially omitted plan view. In the figure, 11... Photosensitive drum, 12... Paper feed guide, 13... Cleaning mechanism, 14... Charger, 15... Transfer corona discharger, 16... Roller, 17... Copy paper, 18 ...Blade, 19
... Holding member, 20 ... Supporting member, 21 ... Frame, 22 ... Screw, 23 ... Guide, 24, 25
...Spring, 26, 27...Support member.

Claims (1)

[Scope of Claims] 1. A blade for removing toner attached to the surface of a photoreceptor drum, a holding member for holding the blade, and a support member for supporting the holding member, wherein the holding member and the support member are In the cleaning mechanism which is rotatably connected to each other approximately in the center, a guide means is disposed in the longitudinal direction between the support member and the cleaning mechanism main body, and one end of the guide means is provided with both ends of the support member. A pair of engaging portions are provided at the other end to engage with a notch provided in the cleaning mechanism main body, and a pair of protrusions are provided at the other end to engage with a biasing means secured to the cleaning mechanism main body. The structure is configured to be rotatable about a support shaft of the guide means, and the biasing force of the biasing means applied to both ends of the guide means and the engagement state between the guide means and the support member at both ends in the longitudinal direction of the guide means are configured to be rotatable about the support shaft of the photoreceptor drum. A cleaning mechanism characterized in that it is capable of following fluctuations of the blade contact position back and forth and up and down.