JPS62157082A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent the overfriction wear of a blade by providing a recovery means which recovers a toner, which is wiped away with a fur brush, from the fur brush and making the quantity of toner recovery of the recovery means different between an image part and a non-image part. CONSTITUTION:In case of cleaning of the image part, a flicker bar 13 is placed in the operating position indicated by a continuous line, and the toner gathered by a fur brush 9 is knocked off by the flicker bar 13 and is recovered from a brush part 9a. The toner remaining after cleaning due to the fur brush 9 is scraped by a blade 10. In case that a cleaning device 7 cleans the non-image part, the flicker bar 13 is moved to a separate position with a shake shaft 14 as the center, and the toner gathered by the fur brush 9 is returned to a position, where it is brought into contact with a drum 1, and is stuck to the drum again and is scraped by the blade 10. In this case, the quantity of toner remaining after transfer is small because of the non-image part, and this part is cleaned sufficiently by only the blade 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention also relates to a cleaning device for cleaning toner remaining on the image bearing member after one transfer by sequentially arranging cleaning blades.

Conventional technology Cleaning devices of the type described above are well known.

In this type of cleaning device, all remaining toner and foreign matter such as paper dust is wiped off from the image bearing member after transfer, such as the photosensitive drum V, with a fur brush, and then the slight amount of remaining toner is scraped off with a blade. It is composed of many parts. Therefore, the toner remaining on the photoreceptor drum is almost completely cleaned, making it a cleaning device with excellent cleaning effects.However, cleaning with a blade may result in too much residual toner or poor cleaning. .

In addition, blade wear may occur due to a very small amount of residual toner, and toner firming may occur on the photoreceptor drum due to toner adhesion.

Therefore, in cleaning By using the fur brush and blade, if the fur brush has almost completed cleaning, the latter problem described above will occur during blade cleaning. This problem almost always occurs when cleaning the non-image area, which is the outside of small-sized paper, between sheets, and for this reason, even in the non-image area, toner is intentionally removed. Other methods have also been proposed, such as attaching .

An object of the present invention is to solve the above-mentioned conventional problems and provide a cleaning device that can prevent excessive friction of the blade even when cleaning is performed using the entire fur brush and blade V in the non-image area. do.

Structure This object has been achieved by the present invention having a collection means for collecting toner wiped with the fur brush from the fur brush, and by changing the amount of toner collected by the collection means between the image area and the non-image area.

The real tM sequence of the present invention will be explained below with reference to the accompanying drawings.

FIG. 1 is a diagram schematically showing the main parts of a copying machine, and numeral 1 in the figure is an image carrier configured as a photosensitive drum. When the main body of the copying machine V is rotated in the direction of arrow A, the charger 2
The drum surface is charged, and this charged portion is cut into a predetermined range by the eraser 3 and is irradiated with light from a document (not shown) as shown by arrow B, thereby forming an electrostatic latent image on the drum surface. . When this latent image passes through the developing device 4, it is developed by toner powder, and the toner image thus formed is transferred onto the transfer sheet 5 fed in the direction of arrow C. The transfer sheet 5, which has been completely transferred, is separated from the drum 1 and sent to a fixing device (not shown). Reference numerals 6 and 6a are chargers used during the above-mentioned transfer and separation operations, respectively.

It is inevitable that a small amount of residual toner will adhere to the surface V of the photoreceptor drum after the transfer has been completed as described above, and after the residual toner is neutralized by the pre-cleaning charger 6b,
It is cleaned by a cleaning device 7. The drum portion that has been cleaned is again neutralized by the static elimination charger e6 cV, and one copying cycle is completed.

The cleaning device 7 has a casing 8 that extends along the photoreceptor drum 1 as shown in FIGS. A fur brush 9 contacts the surface of the rotating drum 1 to wipe off the toner, a blade 1o contacts the surface of the rotating drum 1 with its tip to scrape off the toner, and the toner cleaned by the fur brush 9 and the blade 10 is removed from the entire casing. A collection coil 11 for conveying the toner to the toner, and a sealing member 12 fixedly arranged on the casing to prevent the toner from leaking out of the casing, and the fur brush 9 and the blade 1o are arranged sequentially in the drum rotation direction A. has been done.

The fur brush 9 is made up of a brush part 9a made up of a rotary tube 9b with countless tails, and the blade 10 is made of an elastic material, such as rubber, formed into an elongated shape. (It is configured so that it can come into contact over its entire length.)

The cleaning device 7 configured in this manner first wipes off the toner remaining after transfer and foreign matter such as paper dust with the fur brush 9, then scrapes off the slight amount of toner remaining with the blade 10, and removes the remaining toner with the drum l. removed from

Here, when the amount of toner entering the cleaning device 7 is small, that is, when a non-image area such as between m images or the outer part of a small size transfer paper reaches the cleaning device 7,
Most of the toner is wiped off by the fur brush 9.

Therefore, the contact area of the blade 1° is in a state where the toner, which had been acting as a moisturizer and an activator, is gone, and the blade 1
As previously explained, the frictional force between the drum 1 and the drum 1 suddenly increases, causing various problems.

Therefore, the present invention takes the following measures.

When the fur brush 9 wipes residual toner from the photoreceptor drum 1, it traps the toner in the brush portion a. And if the captured toner remains as it is,
Since the fur brush 9 reattaches to the photosensitive drum 1 without rotation C, when the fur brush 9 moves to a position away from the photosensitive drum 1, it is collected from the brush portion by various collecting means.

The present invention takes advantage of the above phenomenon, and a preferred embodiment thereof will be described below.

In FIG. 2, the fur brush 9 has a collection coil 1]
Retrieval means constructed as a flicker bar 13 are provided near the V to enter into the brush portion a. The flicker bar 13 has a long bar that comes into contact with the entire area of the brush portion 9a, and has an elongated elliptical cross section.
Its upper part protrudes into the brush g (S9a).A swing shaft 14 is fixed to the lower part of both ends of the flicker bar 13, and the swing shaft 14 is rotated at a certain angle by a driving means (not shown). By operating the swing shaft 14, the flicker bar 13 swings between the operating position shown by the solid line where the upper part of the flicker bar 13 protrudes into the brush part 9a and the separated position shown by the chain line where the flicker bar 13 separates from the brush part 9a. It is configured to move.

The cleaning device 7 configured as described above is used for normal cleaning, that is, when cleaning the image area, the cleaning device 7 eliminates flicker.
The bar 13 is located at the operating position V shown by the solid line. Therefore 1
The tatoner collected by the fur brush 9 is knocked off by the flicker bar 13 and collected from the tephra part 9a. After cleaning the fur brush 9, a lot of toner remains, and the toner is scraped off by the blade 1o.

Next, when the cleaning device 7 cleans the non-image area, the flicker bar 13 is moved to the separated position via the swing shaft 14 by the driving means. Therefore, as the fur brush 9 rotates, the toner captured by the fur brush 9 returns to the position where it comes into contact with the drum 1 again and is reattached to the drum. Then, it is scraped off by the blade 10. In this case, since it is a non-image area, the amount of toner remaining after transfer is small, and cleaning can be performed sufficiently with only the blade 10.

In this way, when cleaning the non-image area, the blade 10 and the drum 1 are used to clean the non-image area.
This prevents the frictional force from increasing. Note that the detection of the image area and the non-image area can be obtained from an appropriate detection means such as detection of the front edge or rear edge of the transfer paper or an operation signal of the eraser 3, and the flicker bar 13 is oscillated by the signal. Just let it happen.

Further, as a driving means for swinging the shaft 14 of the flicker bar 13, a solenoid, a cam, or the like can be used.

The width of the photosensitive drum 1 is the width of the maximum document size that can be copied by the copying machine, and when copying onto transfer paper 5 of a size smaller than the maximum size, the unused portion in the width direction of the drum 1 is arise.

Since the charge on this unused portion is removed by the eraser 3, it becomes a non-image portion.

Therefore, as shown in FIG. 3, the flicker bar 13 is divided into a plurality of pieces according to the size of the transfer paper 5.

In the example shown, the maximum size to be copied is A3 size, and the original (not shown) is made using a contact glass (not shown).
This is a copying machine in which one end is set at t2 with reference to all ends. In this case, the flicker bar 13 having the same length as the width of the A3 size is cut off from the left end at each width position of the B5 size, A4 size, and B4 size, and the flicker bar 13 has the same length as the width of the A3 size. It is divided into 18 parts. And each part 15, 16, 17, 18 is a swing axis 1
4, and each part is configured to swing independently. An example of this would be to provide an actuating piano wire belonging to each section in the hollow swing shaft, so that each section 15, 16 can be moved by actuating the piano wire.

17.18″f: They can be swung individually, or four hollow operating shafts with different diameters can be fitted loosely into concentric soil and moved individually (l).

With this configuration, for example, an image (
Also includes reduced images. ) of the flicker bar 13, the portion 15 of the flicker bar 13 is in the full working position and the portions 16, 17 .
By locating each of the 18 fully separated positions, it is possible to prevent the frictional force between the blade 1o and the drum from increasing completely. For example, when using A3 size transfer paper, the flicker bar]3 between each part 15, 16, 17, 18 V
C: It is conceivable that there will be a problem between colleagues and that the toner collection process will be hindered during that time. However, if the spacing is set to about 0.2 to 0.3 cylinders, the brushes may also extend in the axial direction, and the above problem will not occur.

In the above embodiment, the toner is mechanically collected from the fur brush 9V, but it is also possible to collect the toner mechanically.
The entire M column is shown in FIG.

In this example, the photosensitive drum 1 is positively charged, developed with negative toner, and is further negatively charged by a pre-cleaning charger 6b. This cleaning device 7 is equipped with the brush F'HS of the fur brush 9.
9a is composed of conductive fibers made by dispersing acrylic resin V or carbon. and,
A toner collecting means consisting of a bias roller 2o and a scraper 21 brought into contact with the surface of the bias roller 20 is provided on the opposite side of the fur brush 9 from the dirt on the drum 1.

The bias roller 20 has a (3 to 500V) DC power supply 2.
2 are connected, and the DC 1 pressure full bias roller 2
By applying 0, the toner captured by the brush portion 9a is made to adhere to the bias roller 20. A switch 23 is provided between the bias roller 20 and the power source 22.

In the cleaning device 7 thus configured, when the full DC voltage is applied to the bias roller 20, toner adheres to the bias openings to 20 as described above, and the attached toner is scraped off from the bias roller 20 by the scraper 21. Ru. Further, when the applied voltage is turned off by operating the switch 23, the toner captured by the fur brush 9 is removed from the bias roller 2.
Does not shift to 0. Therefore, when cleaning the non-image area, if the switch 23 is turned off, cleaning by the fur brush 9 is not substantially performed as in the previous embodiment, and the toner is scraped off by the blade 10V. Therefore, the friction between the blade 10 and the ram 1 does not increase.

It should be noted that the above switch 23 may be omitted and the voltage applied to the Habia roller 20 may be controlled to be the full Ov in the non-image area.゜Divide the entire transfer paper according to its size and control the voltage applied to each part. Can be turned on and off.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be modified in various ways. For example, the flicker bar is the size of the transfer paper V.
When cleaning the image area, the number of flicker bars corresponding to the transfer paper may be provided so as to be inserted into the fur brush. According to this configuration, there is no cut in the flicker bar. Similarly, a plurality of bias rollers may be provided.

In addition, the image carrier is not limited to the photoreceptor drum, but the belt
Various materials may be used as long as they support a toner image to be transferred, such as a photoreceptor or a transfer drum.

Note that the present invention is naturally applicable not only to cleaning devices for copying machines but also to cleaning devices for facsimile machines, other image recording devices, and the like.

Effects The cleaning device according to the present invention is configured as described above, and since the blade cleans even the non-image area, excessive friction between the blade and the image carrier can be completely prevented.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a double punching machine to which the present invention is applied, FIG. 2 is an enlarged view of the cleaning section in FIG. 1, FIG. 3 is an explanatory diagram showing an example of a flicker bar, and FIG. The figure is an enlarged explanatory diagram showing another embodiment of the present invention. 1... Photosensitive drum, 7... Cleaning device, 9
...Fur brush, 10...Blade, 13...
Flicker bar, 20... bias roller, 21... scraper Figure 1 Figure 3

Claims (3)

[Claims] (1) In a cleaning device that sequentially arranges a fur brush and a blade in the moving direction of the image carrier and cleans the toner remaining on the image carrier after transfer, the toner wiped off by the fur brush is collected from the fur brush. The cleaning device is characterized in that the cleaning device has a collecting means, and the amount of toner collected by the collecting means is changed between an image area and a non-image area. (2) The cleaning device according to claim 1, wherein the collecting means is a flicker bar inserted into a brush portion of a fur brush. (3) The cleaning device according to claim 1, wherein the collecting means includes a bias roller that comes into contact with the brush portion of the fur brush, and a scraper that comes into contact with the bias roller.