JPH01195471A - Wire cleaning device for electrifying device - Google Patents

Abstract

PURPOSE:To exactly execute the cleaning of a wire by moving first and second cleaning members while tracting it, cleaning a charge wire and grid wire and separating the cleaning members with a separating member from the respective wires after the cleaning is finished. CONSTITUTION:When the number of sheets of copies set in advance is achieved, a motor M is energized and a cleaning means 21 is slided in a left direction. The cleaning means 21 is energized in a counterclockwise by a traction means 24 and charge wire cleaning parts 212a-212d are pressed and brought into contact with a charging wire 22. Then, the charging wire 22 is cleaned just like being 'stripped-off' by cleaning cloths 214a-214d. A grid wire cleaning part 217 is pressed and brought into contact with a grid wire 23 and the grid wire 23 is cleaned just like being 'stripped-off' by an elastic member 217a. After the cleaning, the charge wire 22 and grid wire 23 are separated from cleaning members 21a and 21b by a separating member 25. Thus, the respective wires can be cleaned without fail by one cleaning means.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a wire cleaning device for a charging device that cleans a wire stretched across a charging device used in an electrostatic recording device or the like.

[Conventional technology]

2. Description of the Related Art Various types of discharge charging devices using elongated wire-like electrodes are used in image forming units of electrostatic recording devices such as electrophotographic copying machines. These charging devices apply a high voltage to a tungsten wire electrode tens of microns in thickness stretched inside a back plate formed in the shape of a long and thin frame, and apply a charge to the photoreceptor by the corona discharge, or apply a reverse voltage. It is used for the purpose of eliminating static electricity by applying alternating voltage or alternating current voltage to erase the charge on the photoreceptor. In some cases, a grid wire is provided in which a plurality of wires are stretched across the back plate opening of the charging device at regular intervals, and a voltage is applied to the wires to control the corona discharge. As is well known, toner powder, paper powder, or solid matter such as oxide film easily adheres to these electrodes and wires, and when these deposits accumulate, for example, in the case of charged electrodes, the strength of the charge on the photoreceptor decreases. The distribution becomes non-uniform, resulting in uneven density in the copied image. For this reason, since the charging device in particular has a large influence on the image, various cleaning devices are prepared for cleaning the electrodes and wires.

[Problems to be solved by the invention]

Regarding such a cleaning device, proposals have been made in Japanese Patent Publication No. 54-8102 and Japanese Utility Model Publication No. 21-1830. The method proposed in Japanese Utility Model Publication No. 47-30458 has the disadvantage that the charging device must be removed from the body before cleaning, which makes handling complicated and time-consuming. A common drawback of each of the above-mentioned proposals is that the cleaning member is configured to press or press the wire even during charging, so toner powder tends to accumulate on the wire, causing leakage and lowering the potential and changing the electrode position. This has had problems such as biasing the charge distribution and making the charge distribution non-uniform. In addition, if a charging device has a structure in which multiple grid wires are stretched across the opening of the back plate, even if you try to clean the charging wire stretched inside the back plate with your fingers or an alternative tool, the charging device will not be able to hold the grid wires in the opening. There were drawbacks such as the installed grid wires becoming an obstacle and making it difficult to clean thoroughly.

[Means to solve the problem]

The present invention has been made to solve the above-mentioned problems, and provides a wire cleaning device for a charging device that can accurately clean the wire and can separate the cleaning member from the wire during charging. This is the purpose. The above object is to provide a charging device comprising a back plate having a U-shaped cross section, a charge wire surrounded by the back plate, and a grid wire stretched over an opening of the back plate. In the wire cleaning device for a charging device, the wire cleaning device includes a cleaning member that cleans the charging wire by slidingly contacting the charging wire, a first cleaning member that cleans the charging wire, a second cleaning member that cleans the grid wire, and a cleaning member that cleans the grid wire. A sliding guide groove formed on the back surface, a holding member that holds the two cleaning members and moves along the sliding guide groove, and the first and second cleaning members that have moved to the end of the charging device. A separating member that separates the cleaning member from the charge wire and the grid wire, and a drive pulling member that moves the first and second cleaning members are provided, and the first and second cleaning members are pulled and moved to charge the cleaning member. The wire and the grid wire are cleaned, and the first and second cleaning members returned to the end of the charging device after cleaning are separated from the charge wire and the grid wire by a spacing member. This is achieved by a wire cleaning device of the charging device.

【Example】

An embodiment of the present invention is shown in FIGS. 1 to 8. FIG. 2 is a sectional view of a main part of a copying machine equipped with a charging device according to the present invention. In the figure, reference numeral 1 denotes a photosensitive drum that is pivotally supported on the main body of the copying machine. A photoconductive photosensitive layer is provided on the outer peripheral surface of the photosensitive drum 1, and a copy image is formed by passing through each process while rotating the photosensitive drum 1. Around the photoreceptor drum L, there is a charging device 2 that applies an electric charge to the photoreceptor drum L, and a light beam from a light source lamp L is applied to the document on the document platen glass 3, and the photoreceptor layer is exposed to the reflected light and statically charged. A mirror 4.5.6.8 and a lens 7 for forming an electrostatic latent image, a developing device 9 for adhering toner to the electrostatic latent image by electrostatic adsorption, and a transfer device 10 for transferring the toner image onto recording paper. , a separator 11 for separating the recording paper after transfer from the photoreceptor drum 1, and a cleaning section 12 for scraping off toner remaining on the photoreceptor drum l after the transfer, and feeding the recording paper to the transfer device lO. The apparatus includes a paper feeding mechanism (not shown), a fixing device (not shown) for recording paper after transfer and separation, and a paper ejecting mechanism (not shown). FIG. 1 is a perspective view of a main part of a charging device showing an embodiment of the present invention. The figure shows the configuration of the main parts of the charging device of the present invention with the charging surface facing upward. In the figure, 20 is a back plate formed into a rectangular gutter shape. The back plate 20 is made of a steel plate with a thickness of about lff1 m and has a U-shaped cross section, and has a sliding guide groove 20a bored in its back surface. 21 is a cleaning means, and the cleaning means 21 includes a first cleaning member 21a that cleans the charge wire, a second cleaning separation member 21b that cleans the grid wire, and these first and second cleaning members 21b.
and a holding member 21c that holds the cleaning member and moves along the sliding guide groove 20a. 22 is a charge wire, and the charge wire 22 is made of a tungsten wire with a thickness of several tens of microns. The charging wires 22 are stretched over substantially the entire length of the charging device in the longitudinal direction so as to be located near the center of the U-shaped cross section of the back plate 20. 23 is a grid wire, and the grid wire 23 is made of a tungsten wire with a thickness of several tens of microns. A plurality of grid wires 23 are stretched at regular intervals over almost the entire length of the charging device in the longitudinal direction so as to be located near the opening 20b on the side of the charging surface of the back plate 20. 24 is a pulling member of the cleaning means 21, and the pulling member 24 is made of aramid yarn 5upER313 (manufactured by Nippon Weed Co., Ltd.). The traction means 24 is
It acts to pull the cleaning means 21 in conjunction with a drive motor which will be described later. Reference numeral 25 denotes a spacing member, and the spacing member 25 is a guide protrusion integrally formed on a wire block member provided at the end of the charging device. The second cleaning member 21b of the cleaning means 21 engages with this spacing member 25. The second cleaning member 21b is provided with a positioning part 211 consisting of a funnel guiding part and a positioning hole following the guiding part,
When the spacing member 25 engages with the positioning portion 211, the charge wire 22 and the grid wire 23 are separated from the first and second cleaning members. FIG. 3 is an exploded perspective view of the cleaning means 21. 21a is a first cleaning member, and the first cleaning member 21a1
, m ha f yard wire cleaning parts 212a, 212b,
212c and 212d are formed in a protruding manner. Cleaning cloths 214a, 214b, 214c, and 214d are fixed to the contact portions between the charge wire cleaning portions and the charge wire. Further, a support protrusion 213 is formed protrudingly on the first cleaning member 21a and is fitted to support a coil spring 26 that biases a second cleaning member 21b (described later) in a direction to move away from the -1st cleaning member 21a. The first cleaning member 21a
A locking convex portion 215 that engages with a holding member 21c, which will be described later, is formed protruding from the bottom surface of the holding member 21c. Furthermore, the second cleaning member 21
A pair of engagement wings 216a and 216b are provided for engaging the first cleaning member 21a and the first cleaning member 21a. 21b is a second cleaning member, and the second cleaning member 21b
A grid wire cleaning section 217 is provided, and an elastic member 217a is fixed to the sliding contact portion between the grid wire cleaning section 217 and the grid wire 23. Second cleaning member 21
At both ends of b, bifurcated guide clamping parts 218a and 218b that gently engage with the pair of engagement wings 216a and 216b of the first cleaning member 21a are provided.
The cleaning member 216b is provided to face the cleaning member 216b, and after the cleaning members are engaged, the cleaning members can move toward and away from each other in one direction. A projection 219 is provided at the center of the back surface of the grid wire cleaning section 217 of the second cleaning member 21b.
The support protrusion 213 of the first cleaning member 21a is protruded from the support protrusion 213 of the first cleaning member 21a. The first cleaning member 21 is attached to the protrusion 219.
One end of a coil spring 26 that urges the second cleaning member 21a and the second cleaning member 21b apart from each other is engaged, and the engagement ring 24a of the traction means 24 is fitted. The order of attaching these members is to first fit the retaining ring 24a into the protrusion 219, then attach the coil spring 2.
The protrusion 21 is attached to one end of the 6 so as to press the retaining ring 24a.
Attach it to 9. 21c is a holding member, and the holding member 21c is made of a synthetic resin having a relatively low coefficient of friction, such as polyacetal resin. A holding hole 271 is bored in the center of the holding member 21c, and the holding hole 271 and the engagement convex portion 215 of the first cleaning member 21a are loosely fitted. The total length of the retaining convex portion 215 is slightly longer than the total thickness of the retaining member 21c, and the first cleaning member 21a and the retaining member 21c are connected to each other through the sliding guide groove 20a of the back plate 20. Even if the screws 272 are engaged and tightened to the engagement protrusion 215, the first cleaning member 21a and the holding member 21c
is slidable with respect to the back plate 20. The second cleaning member 21a engages with the first cleaning member 21a so as to be able to approach and separate in the vertical direction in the figure, and the first cleaning member 21a and the holding member 21c are engaged with each other by the screw 272, as described above. Since the first and second cleaning members are slidable on the back plate 20, they are held by the holding member 21c and are configured to be movable along the sliding guide groove 20a of the back plate 20. FIG. 4 is a plan sectional view of the charging device of the present invention, showing how the cleaning means 21 is pulled and moved along the sliding guide groove 20a of the back plate 20. A motor M and a worm gear W connected to the motor M are installed on the outside of one end of the back plate 20, and a traction means 24 with a cleaning means 21 attached to a pulley Pi coaxially integrated with the worm gear G. is wound several times. The other end of the traction means 24 is hooked up to a pulley P2. When the number of copies reaches a preset number, the motor M is energized to rotate the worm gear G counterclockwise and slide the cleaning means 21 to the left. FIG. 5 is a plan cross-sectional view showing the cleaning state of the charge wire. This figure is a partially enlarged view of FIG. 4. The traction means 24 urges the cleaning means 21 counterclockwise when pulling the cleaning means 21 to the left by passing around the attachment ring 24a outside the charge wire cleaning parts 212a, 212c; Charge wire cleaning section 212a to 2
12d is pressed into contact with the charge wire 22, and the cleaning cloth 21 is fixed to the charge wire cleaning portion.
The charge wire 22 is "squeezed" by the sliders 4a to 214d, and the charge wire 22 is cleaned by the sliding action. In addition, in FIG. 4, the cleaning means 21 is connected to the sliding guide groove 2.
When it reaches the left end of 0a and stops, a change in the current value applied to the motor M is detected and the energizing circuit is switched.As a result, the motor M rotates in the reverse direction and pulls the cleaning means 21 to its initial position, the right end of the charging device. It reaches the right end and stops. Then, the change in the current value accompanying the stop is detected again, and the motor M
Power is cut off. As shown in FIG. 5, the vicinity of the engagement ring of the pulling means 24 is passed through the outside of the charge wire cleaning section 212a, so when the cleaning means 21 is pulled back to the initial position, The cleaning means 21 is biased clockwise, and the charge wire cleaning sections 212a to 212d are released from the charge wire 22 and no cleaning is performed. The reason why the cleaning means 21 is biased as described above when returning to the initial position is to ensure that the cleaning means 21 is secured to the spacing member 25. Figure 1'6 is a side view in a central cross-sectional view showing the cleaning state of the grid wire. The engaging ring 24a of the traction means 24 is fitted into the protrusion 219 of the second cleaning means 21b, and the coil spring 26 is engaged with the surface of the engaging ring 24a, which presses the grid wire cleaning unit 217 into contact with the grid wire 23. In this way, the grid wire 23 is "squeezed" by the elastic member 217a fixed to the grid wire cleaning section 217, and the cleaning means 21 is slid by the pulling means 24, and the grid wire 23 is cleaned by a sliding action. FIG. 7 is a plan sectional view of the cleaning means showing a state in which the cleaning means 21 is in a standby position (initial position) near the end of the charging device and the charge wire is released from the charge wire cleaning section. The cleaning means 21 completes the cleaning and moves to the traction means 24.
When the wire block 28 is pulled to the right and approaches the standby position, first, as shown in FIG. The funnel-shaped guiding part of the provided positioning part 211 is reached, and the inclined surface of the guiding part is guided by the spacing member 25, so that the separating member 25 and the positioning part 211
It engages and stops so that they fit together. When the cleaning means 21 engages with the spacing members 25, it is slightly rotated clockwise and engaged so that the pair of spacing members 25 and the pair of positioning parts 211 become parallel. In such a locked state, the charge wire cleaning parts 212a to 212d of the first cleaning member 21a also rotate clockwise, so that the charge wire cleaning parts 212a to 212
d are each spaced apart from the charge wire 22. FIG. 8 is a side sectional view of the cleaning means showing a state in which the cleaning means 21 is in a standby position (initial position) near the end of the charging device and the grid wire 23 is released from the grid wire cleaning section. When the cleaning means 21 finishes cleaning and is pulled to the right by the traction means 24 and approaches the standby position, the cleaning means 21 first moves between a pair of spacers integrally provided on the wire block 28 as shown in FIG. The tip of the member 25 is a positioning portion 211 provided on the second cleaning member 21b.
The funnel-shaped guide part is reached, and the inclined surface of the guide part is guided by the spacing member 25, and the spacing member 25 and the positioning part 2
11 are engaged and stopped. Cleaning means 2
1 is moved slightly downward when engaging with the spacing member 25, and engaged so that the -pair of the spacing members 25 and the pair of positioning portions 211 are parallel to each other. In such an engaged state, the grid wire cleaning section 217 of the second cleaning member 21b also pushes down the coil spring 26 and moves downward, so that the grid wire cleaning section 217 and the elastic member 217a are separated from the grid wire 23. be done.

【Effect of the invention】

According to the wire cleaning device for a charging device of the present invention, one cleaning device can be pulled by the traction device and the charge wire and grid wire can be cleaned at the same time, so that the charge wire and the grid wire are always in a clean state. Moreover, since it is possible to separate the cleaning means from the charge wire and the grid wire during the charging operation, the position of the charge wire and the grid wire is also stable, and as a result, a strong and uniform force is applied to the photoreceptor. It has now become possible to provide a wire cleaning device for a charging device that can apply electric charge and obtain stable copied images without image unevenness.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts of a charging device showing an embodiment of the present invention, FIG. 2 is a configuration diagram of essential parts of a copying machine equipped with the charging device of the present invention, and FIG. 3 is a cleaning means according to the present invention. Exploded perspective view of 4th
The figure is a plan sectional view of the charging device showing the state in which the cleaning means is pulled;
FIG. 5 is a plan sectional view of the cleaning means showing the charge wire cleaning state, FIG. 6 is a central sectional view of the cleaning means showing the grid wire cleaning state, and FIG. 7 is a state where the charge wire and the cleaning means are separated. FIG. 8 is a plan sectional view of the cleaning means showing
The figure is a side sectional view of the cleaning means showing a state in which the grid wire and the cleaning means are separated. 2...Charging device 20...Back plate 2
0a...Sliding guide groove 20b...Opening 21...
・Cleaning means 21a...first cleaning member 21b・
... Second cleaning member 21c... Holding member 22... Charge wire 23... Grid wire 24... Traction means 24a... Engagement ring 25... Separation member 26... Coil spring 28 ... Wire block 211 ... Positioning parts 212a, 21
2b, 212c, 212d...Charge wire cleaning part 213...Support protrusion 215...Matching convex part 21
6a, 216b - engaging wing portion 217...grid wire cleaning section 218a, 218b...guiding clamping section M...motor W...two-ohm gear device

Claims (1)

[Claims] The charge wire and the grid wire are brought into sliding contact with a charging device consisting of a back plate having a U-shaped cross section, a charge wire surrounded by the back plate, and a grid wire stretched over an opening of the back plate. A wire cleaning device for a charging device configured to include a cleaning member that cleans the charging wire, a first cleaning member that cleans the charge wire, a second cleaning member that cleans the grid wire, and a hole formed on the back surface of the back plate. sliding guide groove,
A holding member that holds the two cleaning members and moves along the sliding guide groove, and the first and second cleaning members that have moved to the end of the charging device are separated from the charge wire and the grid wire. and a driving traction member that moves the first and second cleaning members,
The first and second cleaning members are towed and moved to clean the charge wire and the grid wire, and the first and second cleaning members, which have returned to the end of the charging device after cleaning, are charged by the spacing member. A wire cleaning device for a charging device, characterized in that it is configured to be separated from a wire and a grid wire.