JPH03263076A - Fur brush cleaner - Google Patents

Abstract

PURPOSE:To restrain toner from scattering from a cleaner by providing a means capable of preventing the occurrence of toner powder smoke even in the case of rotating a fur brush at the time of non-cleaning. CONSTITUTION:The cleaner is provided with a shutter 13 as a means for preventing the occurrence of the toner powder smoke for substantially closing the open part of a fur brush cleaner 7 at the time of non-cleaning, and a roller 9 which is arranged on the downstream side lower than the contact part with an image carrier in the rotating direction of the brush 8 so as to come into contact with the leading end of the fur brush at the time of cleaning and for rotating in the same circumferential speed direction at the circumferential speed equal to or exceeding the circumferential speed at the leading end of the fur brush. And the cleaner is also provided with a means for controlling the fur brush rotating motor so that the rotating speed of the fur brush at the time of non-cleaning may be lower than at the time of cleaning. Then, the open part of the cleaner is closed by the shutter 13 at the time of non-cleaning, and also the roller 9 is rotated in the same circumferential speed direction at the speed equal to or exceeding the speed of the brush 8. Thus, the toner can be restrained from scattering from the cleaner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fur brush cleaner for image forming apparatuses such as copying machines and printers.

[Conventional technology]

In an image forming apparatus such as a copying machine or a printer, an image bearing member such as a photosensitive drum itself, an intermediate transfer belt, an intermediate transfer drum, or a transfer drum around which a transfer material is wound is rotated multiple times. Combine a plurality of toner images and transfer the combined toner image all at once, that is, transfer it onto a transfer material, or if the transfer material is wrapped around a drum, remove the transfer material from the drum and transfer it after the transfer. It is known that the residual toner on the image carrier is cleaned using a fur brush cleaner.

This fur brush cleaner is normally provided so that it comes into contact with the image carrier during cleaning and is spaced from the image carrier when not cleaning.

The toner captured by the fur brush of the cleaner is collected on a collection roller that contacts the fur brush,
It is scraped off from above the collection roller by a blade.

In such a fur brush cleaner, it is desirable to rotate the fur brush to collect toner from the brush even when the fur brush is not being cleaned, that is, when the fur brush is separated from the image carrier.

[Problem to be solved by the invention]

However, when the fur brush in the above-mentioned fur brush cleaner is rotated when it is away from the image carrier and is not being cleaned, the front surface of the cleaner is open.
There is a problem in that the toner is scattered from the cleaner due to the rotation of the fur brush or collection roller and becomes dust, which contaminates the transfer material and the inside of the image forming apparatus.

Therefore, in the fur brush cleaner described above, even when the fur brush is rotated during non-cleaning when the fur brush is separated from the image carrier, toner scattering from the cleaner is significantly suppressed compared to the conventional method. The purpose of the present invention is to provide a fur brush cleaner for cleaning.

[Means to solve the problem]

In order to achieve the above object, the present invention combines a plurality of toner images on an image carrier while the image carrier rotates a plurality of times, and transfers the composite toner images all at once. A fur brush cleaner that cleans residual toner on an image bearing member after image transfer, and the fur brush is provided so that it comes into contact with the image bearing member during cleaning and is separated from the image bearing member when not cleaning. In the brush cleaner, during the non-cleaning time,
The present invention provides a fur brush cleaner characterized in that it is equipped with a means for preventing the generation of toner powder smoke even when the fur brush is rotated.

The means for preventing the generation of toner powder smoke includes: (1) a shutter that substantially closes the opening of the fur brush cleaner during non-cleaning; (2) a cleaning portion of the fur brush, that is, a portion that contacts the image carrier during cleaning; a roller disposed on the downstream side in the rotation direction of the fur brush, which contacts the tip of the fur brush, and is rotated in the same circumferential speed direction at a circumferential speed equal to or higher than the circumferential speed of the tip of the fur brush;
For example, the fur brush rotation motor may be controlled so as to be lower during the non-cleaning period than during the cleaning period.

When the dust smoke prevention roller is employed, the roller may be grounded, or a voltage having the same polarity as the toner to be cleaned may be applied to the roller.

[For production]

According to the fur brush cleaner of the present invention, when the shutter is employed, the cleaner opening is closed by the shutter during non-cleaning, and when the dust smoke prevention roller in contact with the fur brush is employed, the roller is closed. By rotating in the same peripheral speed direction as the brush at or above the same speed, toner scattering from the cleaner and generation of powder smoke are prevented. When the dust smoke prevention roller is used, if it is grounded or a voltage of the same polarity as the toner is applied to it, toner adhesion to the roller is suppressed to that extent.

In addition, when the rotation speed of the fur brush rotation motor is lowered by the rotation speed of the fur brush rotation motor during non-cleaning periods, the centrifugal force applied to the toner on the brush is reduced, thereby preventing toner from scattering from the cleaner and generating dust. .

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

First, one embodiment of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 shows a schematic configuration of a color copying machine using an embodiment of the cleaner.

This copying machine is equipped with a photosensitive drum 1.
A main charger (not shown), an optical system, first, second, and third developing devices each having a different developed color, an intermediate transfer belt 2 (not shown), and a cleaning device, an eraser, etc. (not shown) are provided around the main charger, an optical system, and the like. ing.

As shown in the drawing, the intermediate transfer belt 2 is wound around pulleys 21 to 24 arranged at fixed positions, and is given an appropriate tension by a tension pulley 26, and is moved in the direction of arrow a in the drawing by a pulley drive motor (not shown). Rotationally driven.

On the back side of the portion of the transfer belt 2 facing the photoreceptor drum 1, a primary transfer charger 3 and a secondary static elimination charger 4 are installed.
A secondary transfer charger 5 and a secondary separation charger 6 are provided outside the large pulley 21 on the lower side.

Furthermore, a fur brush cleaner 7 is arranged opposite to which pulley 22 . The fur brush cleaner is
A roller-shaped fur brush 8 that can come into contact with the intermediate transfer belt 2 passing over the pulley 22, a collection roller 9 that comes into contact with the fur brush, a cleaning blade 10 that comes into contact with the collection roller, and a toner transport screw 12 that transports the collected toner. The fur brush 8 rotates around the lower support shaft 11 to a position away from the position where the fur brush 8 contacts the transfer belt 2 (the position shown in Figs. 1 and 3) (see Fig. 4). It can be rotated back and forth.

As shown in FIGS. 1 and 2, in the cleaner 7, the fur brush 8 is moved against the intermediate transfer belt 2 by a spring 17.
A force is applied in the direction of moving away from the On the other hand, the solenoid 1 is attached to the arm 160 fixed to the cleaner casing C.
When the solenoid is turned on, the entire cleaner 7 rotates counterclockwise in FIG. 1 against the spring 17, and the fur brush 8 assumes a position where it contacts the transfer belt 2. Further, when the solenoid 16 is turned off, the spring 17 pulls the entire cleaner clockwise in FIG. 1, thereby separating the fur brush 8 from the belt 2.

According to the color copying machine shown in Fig. 1, charging occurs on the photoreceptor.
The first layer toner image visualized by the first developing device through the exposure and development process is electrostatically transferred by the primary transfer charger 3 onto the intermediate transfer belt 2 which has been cleaned by the contact and drive of the far plan cleaner 7. transcribed. Immediately before the leading edge of the first layer toner image transferred onto this belt reaches the fur brush 8, the fur brush cleaner is separated from the intermediate transfer belt 3 about the support shaft 11 by turning off the solenoid 16, thereby causing the The upper toner image again reaches the part 3 during the primary transfer charge without being disturbed. On the other hand, a second layer toner image is formed on the photoreceptor drum 1 after the first layer toner image using a second developing device, and this second layer toner image is formed on the first layer toner image. The image is transferred onto the transfer belt 2 superimposed on the image.

Similarly, a third layer toner image formed on the photosensitive drum 1 by the third developing device is transferred onto the transfer belt 2 from above the first and second layer toner images.

The composite toner image on the intermediate transfer belt 2, which has been completely composited by overlapping the third layer toner image, is transferred onto a transfer material (not shown) arriving at the secondary transfer charger 5, and The transfer material is separated from the intermediate transfer belt 2 by a secondary separation charger 6 and sent to a fixing device (not shown), where the composite toner image is fixed.

After the secondary transfer by the secondary transfer charger 5 has been completed in this way, the intermediate transfer belt 2 is cleaned by contact with the fur brush 8 by turning on the solenoid 16 in the cleaner 7, and is prepared for the next copying process.

Now, in the fur brush cleaner 7, the fur brush 8 is moved at a circumferential speed of about 230 m++ by a motor (not shown).
/sec, the circumferential speed of the collection roller 9 is approximately 150km/sec.
It is rotated counterclockwise in FIG. 1 at c. Further, the toner conveyance screw 12 is also driven by a motor (not shown).

In this example, the fur brush 8 is a conductive brush with a DC current of -50
0V is applied, and residual toner after toner image transfer is electrostatically attracted from the belt 2 to clean the belt. The collection roller 9 is an aluminum pipe roller to which -1200V is applied, rotates in contact with the fur brush 8, and collects the toner in the brush 8 by adsorption at the contact portion. A cleaning blade 10 that contacts the collection roller 9 is made of urethane rubber, scrapes off the toner adhering to the collection roller 9, and causes the toner to fall onto the conveyance screw 12.

The conveyance screw 12 conveys the falling residual toner to a bottle (not shown).

The cleaner 7 also includes a shutter 13 having an arcuate cross section, and both ends of the shutter are supported by a pair of arms 131 rotatably connected to the cleaner casing C.
Both ends are connected to the rear part of the cleaner casing C by a pair of springs 14 and receive a tensile force there.

A fixed shaft 15 fixed to the copying machine frame is disposed near a pair of arms 131 that support the shutter 13.

When the fur brush 8 is in contact with the belt 2 due to the solenoid 16 being turned on, the shutter support arm 131 is
4, the arm comes into contact with the fixed shaft 15 and stops. In this state, the shutter 13 moves above the cleaner 7, as shown in FIG. 3, and opens the front surface of the cleaner. On the other hand, when the solenoid 16 is turned off and the spring 17 moves the entire cleaner 7 backward, the fixed shaft 15 pushes the shutter support arm 131, and the arm 131 moves counterclockwise in the figure, as shown in FIG. The shutter 13 closes the front opening of the cleaner's fur brush. Thus, even if the fur brush 8 is rotated while the cleaner 7 is in its retracted position and the work of collecting the toner on the fur brush onto the collection roller 9 continues,
Toner scattering and powder smoke generation from the cleaner are effectively prevented.

In place of the fur brush cleaner 7, a fur brush cleaner as shown in FIG. 5 may be used.

A cleaner 70 shown in FIG. 5 includes a fur brush roller 8, a collection roller 9, a toner conveying screw 12, and
Each is equipped with In this cleaner, a powder smoke prevention roller 18 is provided on the downstream side of the cleaning portion of the fur brush 8, that is, the region 80 where the fur brush 8 contacts the belt 2 in the direction of rotation of the brush.

The powder smoke prevention roller 18 comes into contact with the tip of the fur brush 8, and is driven to rotate at or above the circumferential speed of the fur brush 8 in the same circumferential speed direction as the fur brush $, that is, clockwise in the figure. The rotation of the roller 18 is performed by the drive motor of the fur brush 8.

Furthermore, a sealing member 19 made of maltplane or the like is provided between the roller 18 and the casing wall to fill the gap. The roller 18 is grounded or a voltage of the same polarity as the toner is applied, so that toner adhesion to the roller 18 is suppressed as much as possible.

The reason why the roller 18 is provided in this way is that when the fur brush 8 and the collection roller 9 are rotated when the cleaner 7 is separated, the part A and the blade that receive and transfer the collected toner from the fur brush 8 to the collection roller 9 are used. This is because powder smoke is particularly generated in the portion B where toner is scraped off from the collection roller 9 by the brush 8, and the powder smoke generated here flows out of the cleaner through the gap between the brush 8 and the cleaner casing wall. There is an idea that it is sufficient to simply arrange a sealing member in this part, but if the sealing member is arranged here, there is a problem that powder smoke is newly generated due to contact between the sealing member and the brush 8.

Next, still another embodiment will be described based on FIG.

The embodiment cleaner 700 shown in FIG. 6 has substantially the same structure as the cleaner 7 shown in FIG. 1 except that the shirt stopper 13 is not provided. However, a rotation speed switching device 22 that switches the rotation speed of the motor between high and low speeds is connected to the motor 20 that drives the brush 8 and the collection roller 9, and the switching device is connected to a microcomputer CPU that controls the operation of the entire copying machine. motor 20 based on instructions from
Switch the rotation speed. The solenoid 16 also operates based on instructions from the computer.

That is, when the fur brush 8 is in contact with the transfer belt 2 due to the solenoid 16 being turned on, the switching device 22 causes the fur brush 8 to have a circumferential speed of 2301II/sec.
When the motor 20 is rotated so that the collection roller rotates at a circumferential speed of 150x/sec, and the fur brush 8 takes the retracted position where it retreats from the transfer belt 2 by turning off the solenoid 16, the rotational speed of the motor is reduced to about half. The brush 8 is rotated at a circumferential speed of about 110 s/sec, and the collection roller is rotated at a circumferential speed of 73 s/sec. Thus, when the fur brush 8 is retracted, the fur brush 8 and collection roller 9 rotate at a low speed, and the centrifugal force applied to the toner adhering to them is reduced accordingly, making it possible to perform good toner collection without toner scattering.

Although omitted in FIG. 6, the computer CP
Various elements such as a photoreceptor drum drive motor are connected to U.

Although the embodiment described above is a cleaner for an intermediate transfer belt of a color copying machine, the present invention can also be applied to a printer, etc., and can also be applied to a cleaner for a photoreceptor of a drum overlapping type, or a cleaner for a transfer drum of a type that wraps transfer paper. It can also be applied to cleaners.

Furthermore, two or more of the above embodiments may be combined.

〔Effect of the invention〕

According to the present invention, an image after the toner image transfer in an image forming apparatus that combines a plurality of toner images on an image bearing member while the image bearing member rotates a plurality of times and transfers the combined toner images at once. A fur brush cleaner for cleaning residual toner on a carrier, the fur brush being provided so as to come into contact with the image carrier during cleaning and to be spaced from the image carrier during non-cleaning, Even when the fur brush is separated from the image carrier and the fur brush is rotated during non-cleaning, toner scattering from the cleaner is significantly suppressed compared to conventional methods. There is an advantage that these can be collected and removed without fear of contaminating the transfer material or the inside of the image forming apparatus.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a color copying machine employing a cleaner according to an embodiment of the present invention, FIG. 2 is a perspective view of the cleaner shown in FIG. 1, and FIGS. 3 and 4 are views of the cleaner shown in FIG. 1. FIG. 5 is a schematic sectional view of another embodiment of the present invention, and FIG. 6 is a perspective view of still another embodiment of the present invention. 2...Intermediate transfer belt 7.70,700...Fur brush cleaner 8...
Fur brush 9...Recovery roller 13...Shutter 14...Spring 15...Fixed shaft 18...Powder smoke prevention roller 19...Seal member 22...Rotation speed switching device CPU... Microcomputer Applicant Minolta Camera Co., Ltd. 2...Intermediate transfer belt 8...Fur brush 13...Shutter 7...Fur brush cleaner 9...Recovery roller 14...Spring Figure Figure 15 ... Fixed shaft 70 ... Fur brush cleaner 18 ... Powder smoke prevention roller 19 ... Seal member

Claims (5)

[Claims] (1) Image carrier after toner image transfer in an image forming apparatus that combines a plurality of toner images on the image carrier while the image carrier rotates a plurality of times and transfers the composite toner images all at once. A fur brush cleaner for cleaning residual toner on the image carrier, the fur brush being provided so as to come into contact with the image carrier during cleaning and to be separated from the image carrier during non-cleaning. A fur brush cleaner comprising: a means for preventing toner powder smoke generation even when the fur brush is rotated. (2) The fur brush cleaner according to claim 1, wherein the toner powder smoke generation prevention means is a shutter that substantially closes an opening of the fur brush cleaner when the cleaning is not performed. (3) The toner powder smoke generation prevention means is disposed downstream of the cleaning section of the fur brush in the direction of brush rotation, contacts the tip of the fur brush, and moves around the same circumferential speed at or above the circumferential speed of the tip of the fur brush. The fur brush cleaner according to claim 1 or 2, wherein the fur brush cleaner is a powder smoke prevention roller that is rotated in a fast direction. (4) The fur brush cleaner according to claim 3, wherein the dust smoke prevention roller is grounded, or a voltage having the same polarity as the toner to be cleaned is applied to the roller. (5) Claim 1, 2, 3, or 4, wherein the toner powder smoke generation prevention means is a means for controlling the fur brush rotation motor so that the number of rotations of the fur brush is lower during the non-cleaning period than during the cleaning period. Fur brush cleaner as described.