JPH01164986A - Cleaning device for photosensitive body - Google Patents

Abstract

PURPOSE:To maintain cleaning performance at a high level extending over a long period by providing a power source to impress a voltage on a conductive brush and a dust absorbing device in the neighborhood of the conductive brush. CONSTITUTION:A toner scraped from the surface of a photosensitive material 1 by a cleaning blade 2 is stirred mechanically by a toner stirring means 10, and also, the voltage is applied, and the toner from which an attractive force by an electrostatic force is eliminated, then, drops. Since a dropped toner is collected immediately by the dust absorbing device 7 arranged extending over entire length in a longitudinal direction in the neighborhood of the conductive brush 10 that is a stirring means, no toner is accumulated at a wedge part formed between the photosensitive material 1 and the cleaning blade 2. Therefore, no toner remains on the cleaning blade 2 at the time of separating the cleaning blade 2 from the photosensitive material 1, and also, no toner is attached on the blade extending over the long period. In such a way, the cleaning performance can be stabilized and maintained at the high level.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cleaning device for a photoreceptor in a photoreceptor, and more particularly to a photoreceptor cleaning device of a type in which a cleaning blade is brought into pressure contact with a rotating photoreceptor. .

[Prior Art] Conventionally, as a means for cleaning the toner after transfer from the image forming body of an electrophotographic page mount, that is, a photoreceptor, a blade cleaning type 11, which has a simple structure and high cleaning efficiency, has been used. It is being FIG. 6 is a diagram schematically showing the blade cleaning method.

In the figure, 1 is a cylindrical photoreceptor, u2 rotates in the direction of the arrow, a cleaning blade made of polyurethane, etc., and 3 is a recovery roller.

For cleaning (1), the cleaning blade 2 is advanced toward the right in the figure, and the end corner is brought into contact with the surface of the photoreceptor 1 as shown by the dotted line to scrape off the toner remaining on the surface. 11? lL, When the 1-toner images (first color toner image, second color toner image, etc.) that are being formed pass, these toner images must not be disturbed, so the position shown by the solid line is Evacuate and retreat.

During cleaning, the toner scraped off by the cleaning blade 2 falls downward and is collected by the toner collection roller 3 located below toward the toner reservoir.

However, in such a configuration, when the cleaning blade 2 is retracted, a portion of the toner scraped up by the cleaning blade 2 may pass through the cleaning device while remaining attached to the photoreceptor 1.
Toner that has been picked up by the cleaning blade 2 and is falling often adheres to the surface of the photoconductor 1 between the position where the cleaning blade 2 was in contact and the position facing the toner collection roller, and the cleaning blade 2 Since it is in the retracted state, this may cause a cleaning failure in which it passes through the cleaning half without being scraped off.

The toner that could not be completely cleaned moves with the rotation of the photoconductor 1 and spreads or scatters to other parts of the photoconductor surface, causing the charger and developer disposed around the photoconductor 1 to be damaged. This may stain peripheral devices such as a transfer device and a separator, thereby hindering the formation of high-quality images.

Therefore, the present inventors have invented a means for cleaning the toner that has slipped through without being scraped off by the cleaning blade 2 during the retracting operation of the cleaning blade 2, and the applicant of the present application is currently applying for a patent. (Special application 1986-233
019) FIG. 7 is a schematic diagram showing the invention of the above application.

The difference from FIG. 6 is that a cleaning roller 4 with sponge jaws is newly provided.

The cleaning roller 4 is made of urethane foam rubber,
While rotating in the same direction as the rotation direction of the photoreceptor 1 (movements at the contact portion are in opposite directions), contact the surface of the photoreceptor 1,
The residual toner that has passed through the cleaning blade 2 is cleaned by wiping it. Of course, like the cleaning blade 2, this cleaning roller 4 is also designed to move when a toner image that is being formed passes therethrough. Toner that has been wiped off by the cleaning roller 4 and adhered to the surface of the king is scraped off by a scraper 5.

Since the cleaning roller 4 is provided for the above purpose, after the cleaning blade 2 is retracted, it comes into contact with the photoreceptor 1 before the accumulated toner adhering to the photoreceptor 1 arrives, and the cleaning blade 2 is retracted. At the time M, the contact state continues until the portion of the photoreceptor 1 facing the toner collection roller 3 passes the cleaning roller 4, and then retreats.

Cleaning row 54 in actual image forming V & setting
Considering the spacing between the cleaning blade 2 and the toner collection roller 3 and the circumferential distance of the photoreceptor 1, the cleaning roller 4 comes into contact with the photoreceptor 1 immediately after the cleaning blade 2 is retracted, and is retracted in a short time.

[Problem to be solved by the invention 1 The cleaning device described above (Patent No. 11r160-2
No. 33019) discloses a method of thoroughly cleaning the accumulated dirt adhering to the photoreceptor when the cleaning blade is retracted.

However, in addition to the toner recovery device using the toner recovery roller, the mechanism becomes complicated due to the provision of a toner recovery device based on the cleaning roller, and the need for space to dispose the cleaning roller downstream of the cleaning blade. Further, there are other problems such as an instantaneous increase in driving load due to the sponge rubber material coming into contact with the surface of the image forming member.

The present invention has been made in order to solve the above-mentioned problems.In a photoconductor cleaning device having a cleaning blade formed in a drum shape and pressed against the circumferential surface of a rotating photoconductor, the present invention improves cleaning performance, which is the main function for cleaning gutter. To provide a cleaning device for an image forming apparatus that maintains high quality for a long period of time, prevents staining of various devices installed around an image forming body, forms high quality images for a long period of time, and that is clean. What is the purpose?

Means for Solving Problem L] In order to achieve the above object, the present invention provides a photoconductor cleaning device having a cleaning blade formed in a drum shape and pressed against the circumferential surface of a rotating photoconductor. A conductive brush serving as a toner agitating means inserted into a wedge-shaped space formed by a cleaning blade and a photoreceptor and moving relative to the cleaning blade and the photoreceptor; a power source for applying a voltage to the conductive brush; A feature is that a dust suction device is provided near the conductive brush.

[Function] The toner scraped off from the surface of the photoreceptor by the cleaning blade is mechanically disturbed by the toner disturbance means and a voltage is applied to remove the adhesion force due to electrostatic force, causing it to fall. Falling toner is instantly collected by a dust suction device that is placed along the entire length of the hand near the conductive brush that is the toner agitating means, so toner does not accumulate on the photoreceptor and the cleaning blade pattern. .

Therefore, when the cleaning blade leaves the photoreceptor, no toner remains on the photoreceptor or on the cleaning blade, and the area around the image forming member is not contaminated. In addition, since toner does not adhere to the cleaning blade for a long period of time, the cleaning performance remains stable and high. Good quality images can be obtained over a period of time.

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

FIG. 1 is a cross-sectional view showing the main parts of a color copying machine to which the present invention is applied, and FIG. 2 is an enlarged cross-sectional view showing the cleaning device in FIG. 1 with the drive section removed.

In the figure, reference numeral 1 denotes a photoreceptor made of 17 optical conductors (OPC) laminated on a cylindrical l1% body drum, which forms a color toner image while rotating in the direction of the arrow shown in the figure.

That is, the photoreceptor 1 cleaned by the cleaning device 11
The surface of is uniformly charged by a charger 8, and laser exposure 9 is applied to the kiln opening 1 so that a charged latent image corresponding to each color toner image is formed, and the toner of that color is transferred to the developing device 12 (13).
, 14). The above-mentioned charging exposure and development are repeated once for each color (in the case of three colors, it is repeated three times). Charged latent images corresponding to yellow, magenta, and cyan images are formed on the image sensor, and the image information for modulating the laser exposure is provided by a conventionally known color separation image reading device and image processing device. A color toner image is formed on the photoreceptor 1, and to explain the time course, during the first rotation of the photoreceptor 1, a charged latent image corresponding to the yellow toner created by the laser exposure 9 is transferred to the yellow toner developing device 12. By applying a direct current to the developing roller 12-, a yellow toner image is developed on the surface of the photoreceptor 1. In the second rotation of the photoreceptor 1, a magenta toner developing device is activated in the same manner. Magenta toner is adhered to the surface of the photoreceptor 1 by the developing roller 13' of the photoreceptor 1. Further, cyan toner is applied by the developing roller 14' of the cyan toner developing device 14 during the third rotation of the photoreceptor.

The color image thus formed on the surface of the photoreceptor is transferred by a transfer device 16 onto recording paper fed from a paper feeder 15. The transferred recording paper is separated by a separation 317 and then sent to the fixing device 18, where the three color images are fixed on the recording paper. Since the three-color images are combined on the photoreceptor 1 and transferred onto the recording paper in one step, a good image quality b without color shift is obtained. In the above process, the photoreceptor first passes through the cleaning device 11 while carrying a yellow toner image, and then passes through the cleaning device 11 while carrying a yellow toner image and a magenta toner image. In this manner, when an untransferred image passes, the cleaning device 11 is deactivated, and the cleaning device 11 is activated only in other cases. The cleaning device will be explained below with reference to FIG. Reference numeral 2 denotes a cleaning blade constituting the main cleaning means, which is held by a holding device 20 that is driven to rotate about a shaft 19, and is brought into and out of pressure contact with the photoreceptor 1.

10 is a conductive brush material serving as a toner agitating means;
It is held by a member 21, and the holding member 21 is driven to make a linear movement in the depth direction of the apparatus, and is also driven to press against and retreat from the surface of the photoreceptor. Further, the conductive brush material 10 is configured to be applied with an AC voltage of 500 V to 700 V.

Reference numeral 23 denotes a brush squeezing member, which is a means for sufficiently sustaining the function of the brush.

Reference numeral 24 denotes a succincipe pipe, which is connected to a dust collection device and a vacuum pump (not shown).

Reference numeral 6 denotes a suction port having an opening extending over the entire length in the longitudinal direction near the conductive brush 10 and the photoreceptor 1, and is connected to the succincipe pipe over the entire length in the longitudinal direction.

The suction pipe 24, the vacuum pump and the suction port constitute the dust suction device 7.

Next, to explain the operation of the cleaning device, as mentioned above, the cleaning device does not operate as long as an untransferred toner image passes, so the cleaning blade 2
It is held at a distance from the Additionally, the vacuum pump has stopped and the dust suction device does not operate.

Immediately before the residual toner after transfer reaches the opposite position of the cleaning blade 2 of the cleaning device, the cleaning blade 2 is pressed against the photoreceptor 1 by the operation of the holding device. In addition, a vacuum pump was started in the building and the dust suction device was in operation fJ+ state. This state is maintained throughout the passage of the imaged portion. In this way, the residual toner is peeled off from the surface of the photoreceptor by the cleaning blade 2, and is sucked and collected by the dust suction device as shown by the arrow in the figure.

Next, in this device, the cleaning blade is separated from the photoconductor after the transferred residual toner has passed, but at that time, the toner that had accumulated between the cleaning blade and the photoconductor remains on the photoconductor. Before the blade leaves the photoreceptor, the 29 electric brush material 10 enters toward this toner storage part, and the mechanical peeling force due to the gutter disturbance operation of the linear movement II operation and the alternating current voltage are applied. The combined effect with the electric force disturbs and eliminates the toner that remains on the Hti, thereby almost completely removing dirt from the surface of the photoreceptor and the surface of the cleaning blade. Of course, the removed toner is collected by a dust suction device.

The rib where the brush is inserted into the pattern space between the cleaning blade and the photoconductor may be inserted at any time after the blade is pressed into contact with the brush, and even when the brush is withdrawn, it does not affect the leading edge of the toner image in the next copying process. Any time is acceptable as long as it is within the specified time. Also, the voltage application can be turned on and off according to the process.

However, when the conductive brush is inserted toward the toner retention portion, a voltage is applied, and when it is away from the photoreceptor, no voltage is applied.

Although this embodiment uses electric force based on alternating current voltage, the invention is not limited to this, and may also use a superimposed force of direct current and alternating current.

Brush materials include carbon fiber, conductive acrylic fiber, conductive rayon, conductive polynisdel, etc., with a resistance value of 10-3-1010 Ωcm Pj! B
are particularly suitable for use.

Next, the drive mechanism of the holding member 21 of the brush material 10 will be explained with reference to FIGS. 3 to 5.

The flat brush holding member 21 is supported by a sling 1- provided in the casing 22 of the cleaning device so that it can freely move on a flat surface.

Advance J3 and retreat of the holding member 21 in the direction of the photoreceptor 1!
11 ft is achieved by the action of solenoid 42 and spring 53.53. When the solenoid 42 is not energized, the link 51 supported by the shaft 52 is pulled by the spring 53 and is in the position rotated in the rotational direction h1, and is inserted into the elongated hole of the holding member 21. The portion shown is at a position moved to the left, and therefore the brush material 10 held by the holding portion 4121 is at a position separated from the photoreceptor 1.

When the solenoid 42 is energized, the solenoid 42 moves the holding member toward the photoreceptor 1 through a series of links. However, the link 44 supported by the shaft 45 is pulled through the link 43 and rotates in one direction. Link 44 further rotates links 47 and 49, which are supported by shafts 718 and 50, respectively, through pin 46 in the counterclockwise direction and in the counterclockwise direction, respectively. Links 47 and 4
9 also engages links 51.51'' and rotates them in the counter-chronological direction shown in FIG. 5. Links 51.51
- engages with the holding member 21 through a long hole provided therein, and moves it toward the photoreceptor.

Next, a driving mechanism for linear movement of the holding member 21 in the longitudinal direction will be described. The motor 30 rotates an eccentric disc cam 33 integrated with the worm wheel 32 via a worm 31 and a worm wheel 32. The link 35, which is supported by the guides 36 and 36' so as to be able to reciprocate, is pulled by a spring 41 hung between the guide 36' and the pin 37 fixed to the link 35, and the roller 34 which is pivoted to the link 35 is pulled. is in pressure contact with the cam 33, and the cam.

It reciprocates as 33 rotates. A roller 39 attached to a shaft 38 hanging from one end of the link 35 is attached to the holding member 21 via a U-shaped member 40 fixed to the holding member 21.
Therefore, the brush material 10 is linearly reciprocated in the longitudinal direction. In this way, the brush material is brought into contact with and released from the photoreceptor by the operation of the solenoid 42, and linear reciprocating movement in the longitudinal direction is performed by the operation of the motor 30.

Although the present embodiment is configured as described above, the invention is not limited to this and various modifications are possible.

For example, in this embodiment, a trail type is used in which the internal angle formed by the cleaning blade and the photoconductor is an acute angle, but the present invention can also be applied to a counter type in which the internal angle is an obtuse angle. In this embodiment, the vacuum pump of the dust suction device is turned on and off as the dust suction 127 starts and stops, but the vacuum pump is constantly operated and the solenoid valve installed between the vacuum pump and the suction vibrator is used to suck dust. Operation of the device may also be controlled.

[Effects of the Invention] As explained above, in the cleaning device of the present invention, the J3 is provided in the wedge-shaped space between the cleaning blade and the photoreceptor.
The moving brush disturbs and removes the accumulated toner, which removes the accumulated toner at the cleaning point that adversely affects the repeatability of the copying process, and removes toner filming and paper dust. This prevents contamination, extends the life of the cleaning blade as a consumable item, and reduces damage to the photoreceptor.

Further, as an effect of toner removal by the brush, the vicinity of the edge contact portion of the cleaning blade is also cleaned at the same time, which is highly effective in improving and maintaining cleaning performance.

Furthermore, in the case of the present embodiment in which the cleaning blade is released from the pressure bond, there is no need to provide a second toner collecting means, resulting in a compact and inexpensive device configuration, and the load on the mechanical drive is also reduced.

In addition, in the present invention, toner is collected by the 6-type suction system, so compared to mechanical collection methods or electrical collection methods, the reliability against toner spillage is higher, the stability of the device is increased, and the toner is not disturbed and falls. In addition to the toner, toner that adheres to the W3 electric brush and would even harm the disturbance action is also removed, thereby enhancing the toner disturbance removal action of the IS electrical brush.

In this way, the present invention provides a cleaning device that can obtain high-quality images over a long period of time using the conventional blade cleaning method that is easy to use, has high stability, and has good cleaning efficiency.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the main parts of a color copying machine to which the present invention is applied, FIG. 2 is an enlarged sectional view showing the cleaning device 11 in FIG. 1 excluding the drive section, and FIG. FIG. 4 is a front view of the drive mechanism of the tonneau-disturbing brush support member in cleaning device 11 J3, FIG. 5 is a sectional view taken along line A-Δ in FIG. 4, and FIG. FIG. 7 is a sectional view showing an improved prior art cleaning device. 1... Photoreceptor, 2... Cleaning blade, 3...
...Naction pipe, 4...Cleaning roller,
6... Suction port, 7... Dust suction device, 8... Charger, 9... Ray+J'' exposure, 10... Brush material, 1
DESCRIPTION OF SYMBOLS 1...Cleaning device, 12...Yellow 1-toner developing device, 15...Paper feeding device, 16...Transfer device,
17... Separator, 18... Determiner, 19... Axis,
20... Holding device, 21... Maintenance 14i department month, 22.
··casing. t5 1st I M Tea 5 Figure

Claims (1)

[Claims] In a photoconductor cleaning device having a cleaning blade formed in a drum shape and pressed against the circumferential surface of a rotating photoconductor, the cleaning blade is inserted into a wedge-shaped space formed by the cleaning blade and the photoconductor, and the cleaning blade and the photoconductor are inserted into a wedge-shaped space formed by the cleaning blade and the photoconductor. A photoreceptor cleaning device comprising: a conductive brush as toner agitating means that moves relative to the body; a power source for applying voltage to the conductive brush; and a dust suction device provided near the conductive brush.