JPH10186811A - Cleaning device for discharge wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To completely remove the stains sticking to a discharge wire and to prolong the exchange period of the discharge wire by providing the device with cleaning members contactable with the discharge wire and incorporating a polishing agent into these cleaning members. SOLUTION: A shaft part parallel with the discharge wire 503 is formed at a slider body 510b and first and second rotating members 520, 521 are respectively rotatably fitted to the shaft part. Cleaning member supporting plates 520a, 521a which are respectively contactable with both flanks of the discharge wire 503 are formed on the cylindrical surfaces of the first and second rotating members 520, 521. The cleaning members 525 contg. the polishing agent are mounted at the surfaces of the cleaning member supporting plates 520a, 521a which face the discharge wire 503. Particulates of silicon carbide and aluminum carbide are used for the polishing agent. Foamed urethane contg. the polishing agent and nonwoven fabrics adhered with the polishing agent by using adhesives are used as the cleaning members.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning member which slides along a discharge wire such as a transfer / separation electrode of an electrophotographic image forming apparatus, and thereby removes dirt such as oxide adhering to the discharge wire. The present invention relates to a device for cleaning a discharge wire to be removed.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile, a discharge wire is used as a charging device for performing corona discharge on a photosensitive member or a transfer sheet.

[0003] The discharge wire is liable to be contaminated by oxides and the like generated during discharge. When such dirt adheres to the discharge wire, the discharge efficiency is reduced and the life of the wire is shortened, so that periodic cleaning is necessary.

Therefore, a cleaning device as shown in FIGS. 14 and 15 is used. FIG. 14 shows a conventional discharge wire
FIG. 15 is a cross-sectional view taken along section line AA in FIG. 14.

In these figures, reference numeral 1 denotes a discharge wire provided in a back plate (shield plate) 10 provided in parallel with the generatrix of the photoconductor 2, and 4 denotes a discharge wire provided in parallel with the discharge wire 1, not shown. It is a screw rod that is driven to rotate by a motor. The nut 3a and the slider body 3
The nut portion 3a of the slider 3 composed of the screw member b is screwed.

On the bottom surface of the back plate 10, an elongated hole 10a parallel to the discharge wire 1 is formed. Slider 3
The slider body 3b extends into the back plate 10 from above the nut portion 3a through the elongated hole 10a of the back plate 10. Discharge wire 1 is placed on slider body 3b.
Cleaning member mounting plates 5 and 6 so that the
Is provided.

On the surfaces of the cleaning member mounting plates 5, 6 facing the discharge wires 1, cleaning members 8, 9 such as velvet or the like (the cleaning member 8 is not shown) are provided which come into contact with the discharge wires 1. .

Next, the operation of the above configuration will be described. When the cleaning device is stopped, the slider 3 is located at one end of the discharge wire 1. Then, at a predetermined frequency (for example, every 500 image formations or every time the main power supply of the apparatus is turned on), a motor (not shown) is driven, and when the screw rod 4 rotates, the back plate 1 is rotated.
The slider 3 whose rotation is prohibited by the 0 long hole 10a moves along the screw rod 4. Then, when the slider 3 reaches the other end of the discharge wire 1, the motor (not shown) rotates in the opposite direction to the previous direction, and the slider 3 returns to the original position.

When the slider 3 moves along the screw rod 4, the cleaning members 8, 9 slide on the discharge wire 1, and
Dirt attached to the discharge wire 1 is removed.

[0010]

However, the cleaning device for a discharge wire configured as described above has the following problems.

(1) A cleaning member such as a velvet cannot remove stains such as oxides firmly adhered to the discharge wire 1, changes discharge characteristics, and shortens the replacement cycle of the discharge wire 1. (2) Since the cleaning members 8 and 9 are in contact with the discharge wire 1 on both the outward path and the return path, the stain on the discharge wire 1 removed on the outward path may adhere to the discharge wire 1 on the return path.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a cleaning device for a discharge wire which can completely remove dirt attached to the discharge wire and has a long replacement cycle of the discharge wire. It is in.

[0013]

According to a first aspect of the present invention, there is provided a slider movably provided along a discharge wire, and a driving means for reciprocatingly driving the slider along the discharge wire. And a cleaning member provided on the slider and capable of contacting the discharge wire, wherein the cleaning member contains an abrasive.

The abrasive contained in the cleaning member scrapes and removes dirt such as oxide firmly adhered to the discharge wire. Since the dirt is completely removed, the replacement cycle of the discharge wire becomes longer.

Here, examples of the abrasive include fine particles of silicon carbide and aluminum oxide. Also, as a cleaning member,
There are foamed urethane containing an abrasive, and a nonwoven fabric to which an abrasive is attached using an adhesive.

It is desirable that the cleaning member be provided so as to contact the side of the discharge wire, to which dirt is most likely to adhere, on the side facing the photosensitive member. According to a second aspect of the present invention, there is provided a discharge wire cleaning apparatus according to the first aspect, wherein the cleaning member comes into contact with the discharge wire on an outward path and separates from the discharge wire on a return path.

The cleaning member abuts on the discharge wire only on the outward path to remove the stain on the discharge wire, and is separated from the discharge wire on the return path, so that the stain removed on the outward path does not adhere to the discharge wire on the return path. .

The distance between the cleaning member and the discharge wire in the separated state is preferably a distance at which no leak occurs through the cleaning member when the discharge wire is discharged, that is, at least 1 mm or more, preferably 2 mm or more.

According to a third aspect of the present invention, there is provided a dirt collecting member which is located at a rear portion of the cleaning member and which comes into contact with the discharge wire when the slider of the first or second aspect of the present invention moves in a forward movement direction. A cleaning device for a discharge wire.

The dirt collecting section collects dirt adhering to the discharge wire from dirt on the discharge wire shaved by the cleaning member. Examples of the material of the dirt collecting section include flocked fibers and foamed silicone rubber.

[0021]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 9 is an overall configuration diagram of a copying machine provided with a discharge wire cleaning device according to the present embodiment, and FIG. 10 is an enlarged view around an image forming unit in FIG.

First, the overall configuration of the copying machine will be described with reference to FIG. The copier scans the original D on the platen glass 101 with slit-shaped light over the entire surface, and
The light information reflected from the photoconductor 121 is guided to a drum-shaped photoconductor 121 via a mirror, a lens, and the like, and a scanning exposure unit 110 that forms an electrostatic latent image on the photoconductor 121 is formed. An image forming unit 120 that visualizes using the toner (developer) T and transfers the image to the transfer paper P;
Feeding unit 130 that feeds the transfer paper P, a transport unit 140 that transports the transfer paper P, a fixing unit 150 that fixes the toner on the transfer paper P, a discharge switching unit 160, a plurality of paper feed cassettes 170, and duplex copying. And a paper re-feeding device (ADU device) 180.

Next, the image forming unit 120 will be described with reference to FIG. Around the photoreceptor 121, a band electrode 12 that uniformly charges the surface of the photoreceptor 121 by corona discharge
2, a developing unit 123 that visualizes the electrostatic latent image on the photoconductor 121 using toner, and a pre-transfer exposure unit (a pre-transfer exposure unit that lowers the potential by light so that the toner does not adhere to the non-image area on the photoconductor 121) PTL) 124 and photoreceptor 1 by corona discharge
A transfer pole 129a for transferring the toner on the transfer paper 21 to the transfer paper P;
Transfer / separation pole 129 comprising separation pole 129b for separating transfer paper P attached to photoconductor 121 by AC discharge
A separating mechanism 125 for separating the transfer paper P from which the transfer is completed from the photoconductor 121, a static eliminator 126 for removing charges on the photoconductor 121 by corona discharge, and a cleaning unit for removing residual toner on the photoconductor 121. 127 and a pre-charging exposure device (PC) for removing residual charges on the photoconductor 121 by light.
L) 128 are provided.

A discharge wire is provided for the band electrode 122 for performing corona discharge, the transfer / separation electrode 129, and the static eliminator 126. In this embodiment, a discharge wire cleaning device as shown in FIGS. 1 to 6 is provided in order to remove stains such as oxides generated when the discharge wire is discharged.

FIG. 1 is a perspective view of a main part of an apparatus for cleaning a discharge wire of a transfer pole according to an embodiment of the present invention. FIG. 2 is a sectional view of FIG.
3 is an exploded perspective view of a main part in FIG. 1, FIG. 4 is a right side view in FIG. 2, FIG. 5 is a perspective view of a main part of a block 501 in FIG. 4, and FIG. 6 is a block 502 in FIG. FIG. In the present embodiment, a description will be given of a cleaning device for a discharge wire of the transfer pole 129a as an example.

In FIG. 2 and FIG. 4, reference numeral 500 denotes a back plate which is disposed in parallel with the generatrix of the photoreceptor 121 and has a U-shaped cross section in which the surface facing the photoreceptor 121 is open. Blocks 501 and 502 are provided at both ends of the back plate 500, and these two blocks 50 and 502 are provided.
A discharge wire 503 is stretched between 1,502 so as to be parallel to the generatrix of the photoconductor 121.

Below the bottom surface of the back plate 500,
One end is rotatably supported by a bearing 506, and the other end is provided with a screw rod 505 connected to a motor 507. The screw rod 505 has a nut 510 of the slider 510 including a nut 510a and a slider body 510b.
a is screwed.

An elongated hole 500a parallel to the discharge wire 503 is formed on the bottom surface of the back plate 500, and a slider body 510b of the slider 510 has a nut portion 510a.
And extends into the back plate 500 through the elongated hole 500a.

Next, in FIGS. 1 and 3, a shaft portion 510c parallel to the discharge wire 503 is formed on the slider body 510b. In the shaft portion 510c,
A cylindrical first rotating member 520 and a first rotating member 52;
0 and the adjacent second rotating member 521 are rotatably fitted to each other.

A cleaning member support plate 520a is formed on the cylindrical surface of the first rotating member 520 so as to be in contact with one side surface of the discharge wire 503, and a discharge member is formed on the cylindrical surface of the second rotating member 521. A cleaning member support plate 521a that can contact the other side surface of the wire 503 is formed.

Cleaning member support plates 520a, 521a
Cleaning members 525 and 526 containing an abrasive are attached to a surface facing the discharge wire 503. In the present embodiment, fine particles of silicon carbide or aluminum oxide are used as the abrasive, and urethane foam containing the abrasive or a nonwoven fabric to which the abrasive is attached using an adhesive is used as the cleaning member. Using.

The intermediate portion is wound around the cylindrical surface of the first rotating member 520, and one end portion is wound around the first rotating member 52.
0 of the cleaning member support plate 520a of the second rotating member 521.
The cleaning member support plate 520a of the first rotating member 520 is provided by the torsion coil spring 523 locked to the first rotation member 520a.
And the cleaning member support plate 52 of the second rotating member 521
1a is urged in a direction to clamp the discharge wire 503. The urging force of the screw coil spring 523 is set to be about 3 to 30 gf at the cleaning member support plates 520a and 521a.

A groove 521b extending in the axial direction is formed on the cylindrical surface of the second rotating member 521. Reference numeral 524 denotes a lock member having a hole 524a into which the cylindrical surface of the second rotating member 521 fits and a projection 524b engaging with the groove 521b of the second rotating member 521. Therefore, the locking member 52
4 is prohibited from rotating with respect to the cylindrical surface of the second rotating member 521, and is movable only in the axial direction of the second rotating member 521. Further, the lock member 524 is engaged with the respective opposing surfaces of the cleaning member support plate 520a of the first rotating member 520 and the cleaning member support plate 521a of the second rotating member 521, and the cleaning support plates 520a,
Lock claws 524c and 524d are formed at positions where 1a is charged and separated from the discharge wire 503, and prohibit further movement of the discharge wire 503 in the clamping direction.

As shown in FIG. 5, the block 501 of the back plate 500 extends in the same direction as the direction in which the discharge wire 503 extends, and the first and second rotating members 520, 5
A first guide plate 530 having a pointed tip 530a formed at the distal end thereof, which can be fitted between the cleaning support plates 520a and 521a of FIG. 21 and whose width gradually decreases toward the distal end; It extends in the same direction as the extending direction, can be fitted between the cleaning support plates 520a, 521a of the first and second rotating members 520, 521, and can contact the lock claws 524c, 524d of the lock member 524. First and second lock release bars 531 and 532 are provided.

The block 5 of the back plate 500
6, the first and second rotating members 52 extend in the same direction as the direction in which the discharge wire 503 extends, as shown in FIG.
A second guide plate 540 having a pointed head 540a which can be inserted between the cleaning support plates 520a and 521a of the first and second cleaning support plates 520a and 521a, and whose width gradually decreases toward the front end portion; 503 extends in the same direction as the extension direction of the lock member 524 (block 502).
A lock plate 541 is provided which can abut on the opposite surface.

Next, the operation of the above configuration will be described with reference to FIGS. 7 and 8, the torsion coil spring 523 is omitted. Further, in the present embodiment, the block 501 side is set as the home position.

(1) When the slider 510 is at the home position (see FIG. 7) The first guide plate 530 is used as the cleaning support plate 520.
a, 521a, and the cleaning member support plates 520a, 521a, which are urged by the torsion coil spring 523 in the direction of sandwiching the discharge wire 503,
Of the discharge wire 5
It is located far enough from 03.

The first and second unlocking bars 53
1, 532 are lock claws 524c, 52 of the lock member 524.
4d, the lock claw 524c of the lock member 524 is pressed.
Reference numeral 524d is in a disengaged position with the cleaning member support plates 520a and 521.

(2) Block 502 from home position
When the control unit (not shown) drives the motor 507 in the normal rotation direction, the screw rod 505 rotates, and the slider 510 whose rotation is prohibited by the elongated hole 500 a of the back plate 500.
Starts moving along the threaded bar 505 toward the block 502.

At this time, the cleaning member supporting plates 520a and 521a pressed against the side surface of the first guide plate 530 by the torsion coil spring 523 move while sliding on the side surface of the first guide plate 530, and are cleaned. When the member support plates 520a and 521a pass the pointed head 530a of the first guide plate 530, the first and second cleaning member support plates 520a and 521a pinch the discharge wires 503 by the urging force of the torsion coil spring 523. In the direction of the block 502 while the cleaning members 525 and 526 sandwich the discharge wire 503.

Then, the abrasive contained in the cleaning members 525 and 526 removes dirt such as oxide firmly adhered to the discharge wire 503 by removing it. (3) Arriving at the block 502 (see FIG. 8) When the slider 510 moves to the vicinity of the block 502,
First, the cleaning member supporting plate 520 in which the point 540a of the second guide plate 540 is urged by the torsion coil spring 523 in the direction to sandwich the discharge wire 503.
a and the cleaning member support plate 521a. When the slider 510 continues to move in the direction of the block 502, the cleaning member supporting plates 520a, 521
a is guided by the side surface of the second guide plate 540 and moves in a direction away from the discharge wire 503.

Then, the lock plate 541 pushes the back surface of the lock member 524, and the lock member 524 is
24c and 524d are cleaning member support plates 520a and 52
It moves to a position where it can engage with 1.

When the load current of the motor 507 increases due to the slider 510 hitting the block 502 and exceeds a certain value, a control unit (not shown) drives the motor 507 in the reverse direction.

(4) Return from Block 502 to Home Position When the motor 507 rotates in the reverse direction, the slider 510 starts moving in the direction of the block 501 (home position).

The cleaning member support plates 520a and 521a pressed against the side surface of the second guide plate 540 by the torsion coil spring 523 move while slidingly contacting the side surface of the second guide plate 540, and the cleaning member support plate is moved. 520a and 521a are the second guide plate 54
0, the torsion coil spring 52
3, the first and second cleaning member support plates 520a and 521a try to move in the direction of holding the discharge wire 503, but the lock claws 524c and 524d of the lock member 524 are moved by the cleaning member support plates 520a and 520a. 5
Since the first and second cleaning member support plates 520a and 521a have been moved to the position where they can be engaged with the lock member 21, the first and second cleaning member support plates 520a and 521a engage with the lock claws 524c and 524d of the lock member 524, and further movement is prohibited. You. That is, the cleaning member 52
5,526 is separated from the discharge wire 503,
The slider 510 returns to the home position.

(5) Arriving at the home position When the slider 510 moves to the vicinity of the block 501,
First, the pointed portion 530a of the first guide plate 530 enters between the cleaning member support plate 520a and the cleaning member support plate 521a, and the first and second lock release bars 531 and 532 are connected to the lock member 524. Press the claw and lock member 524 is locked claw 524c, 524d
Is pushed to the position where it does not engage with the cleaning member support plates 520a and 521a.

When the engagement between the lock claws 524c and 524d and the cleaning member support plates 520a and 521a is released, the cleaning member support plates 520a and 521a are moved by the first guide plate by the urging force of the torsion coil spring 523. 530.

Then, the slider 510 is moved to the block 501.
When the load current of the motor 507 rises and exceeds a certain value, the control unit (not shown) stops driving the motor 507 and ends a series of operations.

According to the above configuration, the cleaning members 525, 52
6 contains an abrasive so that the abrasive is
Dirt such as oxide firmly adhered to 3 can be scraped off and dirt can be removed.

Since the dirt is completely removed, the replacement cycle of the discharge wire 503 becomes longer. Also, the cleaning member 5
The cleaning members 525 and 526 abut the discharge wire 503 only in the forward path to remove dirt from the discharge wire by contacting the discharge wire 503 in the outward path and separate from the discharge wire 503 in the return path. The contaminated dirt does not reattach to the discharge wire on the return path.

The present invention is not limited to the above embodiment. In the above-described embodiment, the cleaning member is sandwiched from the left and right directions of the discharge wire 503 as shown in FIG. 11A. However, as shown in FIG. That is, a configuration may be adopted in which a portion of the discharge wire 503 facing the photoconductor 121 is sandwiched.

In the above embodiment, as shown in FIG. 12A, the cleaning members 525 and 526 are provided so as to face each other with the discharge wire 503 interposed therebetween. However, as shown in FIG. They may be arranged shifted from the traveling direction.

Further, as shown in FIG. 13, on the slider body 510b, a dirt collecting portion 600 which contacts the discharge wire 503 may be provided. According to such a configuration, the dirt collection unit 600 is located at the rear of the cleaning members 525 and 526 when the slider 510 moves in the forward path, and the cleaning members 525 and 526 are located.
Among the dirt on the discharge wire 503 shaved by 526, the dirt attached to the discharge wire 503 can be collected.

[0054]

As described above, according to the first aspect of the present invention, the cleaning member contains an abrasive, so that the abrasive removes dirt such as oxides firmly adhered to the discharge wire, Dirt can be removed.

Since the dirt is completely removed, the replacement cycle of the discharge wire becomes longer. According to the second aspect of the present invention, the cleaning member according to the first aspect of the present invention abuts on the discharge wire on the outward path and separates from the discharge wire on the return path, so that the cleaning member contacts the discharge wire only on the outward path. The contact wire removes dirt from the discharge wire and separates from the discharge wire on the return path, so that the dirt removed on the outward path does not adhere to the discharge wire on the return path.

According to the third aspect of the present invention, when the slider of the first or second aspect of the present invention moves in the forward path, the dirt collecting member which is located at the rear of the cleaning member and abuts on the discharge wire is provided on the slider. , The dirt collecting unit can collect the dirt attached to the discharge wire among the dirt on the discharge wire shaved by the cleaning member.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a device for cleaning a discharge wire of a transfer pole according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along section line BB of FIG. 1;

FIG. 3 is an exploded perspective view of a main part of FIG.

FIG. 4 is a right side view in FIG.

FIG. 5 is a perspective view of a main part of a block 501 in FIG. 4;

FIG. 6 is a perspective view of a main part of a block 502 in FIG.

FIG. 7 is a diagram illustrating an operation.

FIG. 8 is a diagram illustrating an operation.

FIG. 9 is an overall configuration diagram of a copying machine provided with a discharge wire cleaning device of the present embodiment.

FIG. 10 is an enlarged view around an image forming unit in FIG. 9;

FIG. 11 is a diagram illustrating another embodiment.

FIG. 12 is a diagram for explaining another embodiment.

FIG. 13 is a diagram illustrating another embodiment.

FIG. 14 is a configuration perspective view of a conventional discharge wire (transfer electrode) cleaning device.

FIG. 15 is a sectional view taken along a cutting line AA in FIG. 14;

[Explanation of symbols]

 503 Discharge wire 510 Slider 525, 526 Cleaning member

Claims (3)

[Claims] 1. A slider movably provided along a discharge wire, driving means for reciprocatingly driving the slider along the discharge wire, and a slider provided on the slider and capable of abutting on the discharge wire. An apparatus for cleaning a discharge wire, comprising: a cleaning member, wherein the cleaning member includes an abrasive. 2. The discharge wire cleaning apparatus according to claim 1, wherein the cleaning member comes into contact with the discharge wire on the outward path and separates from the discharge wire on the return path. 3. The discharge according to claim 1, wherein a dirt collecting member that is located at a rear portion of the cleaning member when the slider moves in a forward direction and is in contact with the discharge wire is provided on the slider. Wire cleaning device.