JPH03134679A - Automatic cleaning device for charger - Google Patents

Abstract

PURPOSE:To enable automatic cleaning sufficiently over the whole periphery of a charging wire by turning a rotation supporting member, which is reciprocatively moved while housing a cleaning member to crimp a charging wire, through an arm guide. CONSTITUTION:In a rotation supporting member 14, two cleaning members 13 are provided to execute cleaning while crimping a charging wire 2a of the charger and this member 14 is reciprocatively moved along the wire 2a. The member 14 is turned at 90 deg., etc., by arm guides 24 and 25 of a rotating means provided in a reciprocative moving end and an arm part 12a of the rotating means, etc., and the whole periphery of the changing wire is sufficiently automatically cleaned without remained parts.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic cleaning device for a charger of an image forming apparatus that employs electrophotography, such as a copying machine or a printer.

(Prior Art) For example, around a photosensitive drum, which is an image bearing member of a copying machine, there is a primary charger for uniformly charging the photosensitive drum, and a primary charger for transferring a toner image formed on the photosensitive drum onto transfer paper. Transfer charger etc. are installed.

A charging device such as a forming charger or a transfer charger has a charging wire installed in a space surrounded by a shield, and by applying a voltage to the charging wire, a corona is directed toward the photosensitive drum. This generates a discharge and gives a positive or negative charge to the photosensitive drum.

If toner, oil mist, dust, etc. scattered within the apparatus adhere to the charging wire of the charger, normal discharge cannot be performed, and it becomes difficult to form an image properly with this charger. Therefore, it becomes necessary to clean the dirt attached to the charging wire, and for this purpose, the charging wire generally has a seventh
As shown in the figure, the charging wire 100 is sandwiched between a pair of cleaning members 101 and 101, and the cleaning members 101 and 101 are moved along the charging wire lOO to clean the charging wire lOO. An automatic cleaning device is installed.

(Problem to be Solved by the Invention) However, the charged wire 100 is connected to a pair of cleaning members 101.
101, a pair of cleaning members 101.101
A peeling portion is generated by the charged wire 100 at the seam 102 of
Therefore, spaces 103, 103 are created in the charging wire ZOO@, and there are portions where the cleaning member 101, 101 and the charging wire lOO do not come into contact. Therefore, if there is a deposit 110 around the charged wire 100 as shown in FIG.
00, some of the deposits 110 remain as shown in FIG. 8(b), and there is a problem in that proper image formation cannot be performed using such a charger.

The present invention has been made in view of the above problems, and an object thereof is to provide an automatic cleaning device for a charger that can sufficiently clean the entire circumference of a charging wire.

(Means for Solving Problem 71) In order to achieve the above object, the present invention provides a cleaning member made of a flexible member that clamps a charged wire to a support member that automatically reciprocates along the charged wire. In an automatic charger cleaning device that cleans the outer periphery of a charging wire with the pair of cleaning members, when the supporting member comes to at least one end of the charging wire, the supporting member is moved around the charging wire by a predetermined amount. The invention is characterized in that it is provided with a rotating means that rotates by .

(Function) When the cleaning member pair and its supporting member come to at least one side of the charged wire, the supporting member and the cleaning member pair are rotated by a predetermined amount around the charged wire, so that the cleaning member moves along the charged wire. With this pair of cleaning members, the outer periphery of the charging wire can be cleaned without leaking. That is, for example, even if a non-contact part is created between the cleaning member pair and the charged wire during the first cleaning and the charged wire is not sufficiently cleaned, the cleaning by the cleaning member pair after the second cleaning after the cleaning member pair rotates. Accordingly, it is possible to eliminate non-contact portions of the pair of cleaning members with respect to the charging wire, and the charging wire can be sufficiently cleaned.

(Example) Examples of the present invention will be described below with reference to the accompanying drawings, taking a copying machine as an example.

First, an outline of the image forming operation by a copying machine will be explained with reference to FIG. 1. In the figure, 1 is a photosensitive drum which is an image bearing member, and around the photosensitive drum 1 there is a primary charger 2. A developing device 3, a transfer charging device 4, and a cleaning device 5 are provided. That is, when the photosensitive drum 1 uniformly charged by the primary charger 2 is exposed to only image light from a document (not shown), an electrostatic latent image is formed on the photosensitive drum 1 according to the image light. The electrostatic Ns image moves toward the developing device 3 as the photosensitive drum 1 rotates, is developed with toner in the developing device 3, and is visualized and converted into a toner image. This toner image is then transferred via a transfer charger 4 onto a transfer paper P that is conveyed from a paper feed system (not shown).The transfer paper P carrying the 0-order toner image is transferred to a fixing device (not shown). The toner image is fixed as a permanent image on the transfer paper P, and the photosensitive drum L after the transfer is cleaned of residual toner by the cleaning device 5, and the same operation is repeated successively. An image is formed on the transfer paper P.

Now, the primary charger 2 and the transfer charger 4 generate a corona discharge toward the photosensitive tram l by applying voltage to the charging wires 2a and 4a surrounded by the shield.
It gives a positive or negative charge to the photosensitive drum l,
If toner, oil mist, dust, etc. scattered inside the device adhere to the charging wires 2a and 4a of these chargers 2.4, normal discharge will no longer be possible and the charger will no longer be able to function satisfactorily. becomes. Therefore, many chargers are generally equipped with an automatic charging wire cleaning device.

Therefore, the automatic charging device cleaning device according to the present invention will be explained by taking the negative charger 2 as an example.

First, a first embodiment of the present invention will be explained with reference to FIGS. 2 to 5.

FIG. 2 shows a perspective view of the primary charger 2, in which the left and right charging blocks 10 and 11 are U-shaped shield members 1.
2, and a charging wire 2a is disposed in tension between the left and right charging blocks 10 and 11 in the shield member 12. As shown in FIG. 3, the charged wire 2a is sandwiched between cleaning members 13.13 made of a pair of flexible members, and the charging is removed by the movement of the cleaning member 13.13 along the charged wire 2a. The outer periphery of the wire 2a is cleaned by the cleaning member 13.13. The pair of cleaning members 13.13 are attached to a grip portion 14a provided at the center of the rotating support member 14, which has a substantially cylindrical shape with a portion open.
13 are pressed against each other by the gripping portion 14a and are placed in a pressurized state so as to wrap around the charging wire 2a.

The lower half of the rotary support member 14 is held rotatably around the charged wire 2a in an anti-cylindrical holding table 15 whose lower half is sealed at both ends. 15 Arm portion 14b outward along charging wire 2a
protrudes, and therefore, due to the weight of the arm portion 14b, the rotary support member 14 is supported on the holding base 15 in a rotated state until the arm portion 14b is horizontally supported by the upper end portion 12a of the shield member 12. There is. Therefore, in this case the cleaning member 13.13 is connected to the charging wire 2, as shown in FIG.
A is sandwiched from both the front and rear sides.

The lower part of the holding table 15 has horizontal upper and lower guide parts 15b and 15c.
It has a horizontally shaped (H) shape with vertical sliding parts 15a connecting the parts, and the bottom part 12b of the shield member 12.
A guide hole 12 formed along the charging wire 2a in the center of the
The sliding part 15a of the holding base fits into b-1, and the bottom part 12b of the shield member 12 is inserted into the upper and lower guide parts 15b and 15c.
are sandwiched from above and below, and the holding stand 15 is supported on the shield member 12 so as to be slidable along the guide hole 1zb-i.

Further, as shown in FIG. 4, a pulley 21 is attached to the drive shaft on the lower side of the left charging block lO. ：Li connected stepping motor 20 is supported, and the right charging block l
A pulley 22 corresponding to the pulley 21 is also pivotally supported on the pulley 1, and an endless timing belt 23 is wound between the pulleys 21 and 22. As shown in FIGS. 3 and 4, a part of the timing belt 23 is connected to the upper guide portion 15b of the holding stand 15, so that the holding stand 15 is moved from the shield member 12 by the rotation of the slapping motor 20. It moves between the left and right charging blocks to and ti along the guide hole 12b-1.

Further, as shown in FIG. 2, arm portions of the rotation support member 14 are located near the left and right charging blocks 10.11 when the rotation support member 14 moves to the vicinity of the left and right charging blocks 10.11. 14b to rotate this rotational support member 14.
Left and right arm guides to rotate by 90 degrees 24.25
is attached on the shield member 12. As shown in FIG. 3, the right arm guide 25 lifts the outer end of the arm portion 14b of the rotary support member 14, which is moving horizontally over the upper end portion 12a of the shield member 12, upward and moves the rotary support member 14 by 90 degrees counterclockwise in FIG.
The state of the figure! A guide surface such as t4) is formed on the upper part. Further, the left arm guide 24 is also formed with a guide surface similar to the right arm guide 25, and the arm portion 14b of the rotation support member 14 positioned upward is connected to the shield member 1.
It has the function of rotating 90 degrees clockwise in FIG. 5 up to the upper end 12a of FIG.

Thus, a voltage is applied to the charging wire 2a of the negative charger 2,
While the primary charger 2 uniformly charges the photosensitive drum 1 by causing corona discharge through the charging wire 2a, the holding table 15 having the rotary support member 14 is mounted on the left arm near the left charging block in FIG. It is positioned close to the guide 24.

Therefore, in this case, the rotation support member 14 has its arm portion 14b.
The left arm has been rotated by 24 until it is in a horizontal position as shown in FIG.

The pair of cleaning members 13, 13 sandwich the charging wire from both the front and rear sides.

To start cleaning the charging wire 2a, the stepping motor 20 is rotated forward and the timing belt 23 is moved clockwise as shown in FIG.
The rotary support member 14 in the holding metalwork 5 is also placed on both ends of the holding stand 15 and moves together with the holding stand 15. Therefore, due to the movement of the rotation support member 14, the charging wire 2a has its front and rear surfaces facing the cleaning member 13.13.
It will be cleaned by.

When the holding table 15 moves toward the right charging block 11 and the arm portion 14b of the rotation support member 14 begins to move on the guide surface of the right arm guide 25, the arm portion 14b is lifted upward and the rotation support member 14 is moved toward the right charging block 11. 14 is 90 until the arm part 14b is in the state shown in FIG. 5 located on the upper side.
Rotate degrees. In this case, the cleaning member 13.13 is the charged wire 2a.
are sandwiched from above and below. Also, the arm portion 14
When b is facing upward, no rotational torque acts on the rotation support member 14, so if there is a certain amount of frictional resistance between the rotation support member 14 and the holding table 15, the rotation support member 14 will move into the holding table 15. It will be supported in a stable state.

When the arm portion 14b of the rotation support member 14 reaches the upper part,
The stepping motor 20 once stops and then reverses to move the holding table 15 toward the left charging block 10. Therefore, the rotation support member 14 also moves toward the left arm guide 24, and the charging wire 2a is cleaned by the cleaning member 13.13 from above and below. Then, when the arm portion 14b of the rotation support member 14 begins to engage with the guide surface of the left arm guide 24, the arm portion 14b returns to the horizontal state as shown in FIG. 3, and the entire rotation support member 14 is rotated by 90 degrees. The cleaning members 13, 13, etc. are returned to their original states.

In this way, the charging wire 2a is cleaned by the gI sweeping members 13.13 moving forward, backward, upward and downward.

Due to the nature of the flexible cleaning member 13.13, its entire circumference is cleaned along its length.

Next, a second embodiment of the present invention will be described with reference to FIG. 6 and the like. Components having the same functions as those in the first embodiment are designated by the same reference numerals, and their explanations will be omitted.

In this embodiment, the rotary support member 14 does not have an arm portion 14b, and the rotary support member 14 has a complete cylindrical shape.
It is rotatably supported inside. Therefore, the left and right arm guides 24.25 are placed near the left and right charging blocks 10.11.
The rotation of the zero-rotation support member 14, which is not provided, is controlled by the second stepping motor 30 provided on one side of the holding table 15, and the rotation of the second stepping motor 30 is controlled by the rotation support member 1.
This is done by two friction pulleys 31 and 32 that transmit the signal to the 4.

That is, the holding table 15 is moved from the vicinity of the left charger block 10 to the right charger block 11 by the rotation of the stepping motor 20.
At the stage of moving toward the charging wire 2a, the charging wire 2a is cleaned from the front and rear directions by a cleaning member 13.13, as shown in FIG. 6, for example. When the holding table 15 moves to the vicinity of the right charging block 11, the second stepping motor 30
rotates, and the rotational support member 14 rotates by a certain amount (this amount may be arbitrary) via the two friction pulleys 31 and 32, and the second stepping motor 30 stops, and the stepping motor 20 The holding table 15 is reversely moved toward the left charging block 10. This allows the cleaning member 13.13 to clean the charged wire 2 from two fixed directions.
A will be cleaned. When the holding table 15 comes close to the left charging block 10, the rotation support member 14 is rotated by a certain amount again via the second stepping motor 30, and then the stepping motor 20 is returned to normal rotation and the same operation is repeated. By repeating the above steps, the charged wire 2a will be connected to the cleaning member 13.
．． 13, cleaning is performed from various directions.

As described above, in this embodiment, since the amount of rotation of the rotation support member 14 can be determined arbitrarily, the charging wire 2 of the holding base 15
By moving along the line a multiple times, the m electric wire 2a is sufficiently cleaned by the cleaning member 13.13 from multiple directions.

(Effects of the Invention) As is clear from the above description, according to the present invention, after cleaning the charged wire by moving the cleaning member that clamps the charged wire along the charged wire, the cleaning member is moved through the support member. Since the cleaning member rotates around the charging wire and performs similar cleaning, the outer peripheral portion of the charging wire can be thoroughly cleaned.

Therefore, since the charging wire can be cleaned without leaving any deposits on the charging wire, proper image formation can be performed using such a charger.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the outline of image forming work by a copying machine, FIG. 2 is a perspective view of a primary charger equipped with an automatic charger cleaning device according to the first embodiment, and FIG. A- in Figure 2
4 is an explanatory diagram of the moving mechanism of the holding table of the automatic cleaning device of the same charger, FIG. 5 is an explanatory diagram of the operation of the automatic cleaning device of the same charger, and FIG. 6 is a diagram of the second A vertical cross-sectional view of a primary charger equipped with an automatic charger cleaning device according to an embodiment, and FIGS. 7 and 8 are explanatory diagrams of the prior art. 2a, 4a...Charging wire, 12a...Arm part (rotation means), 13...Cleaning member, 14...Rotation support member (support member), 24.25...Arm guide (rotation means) ), 30...second stepping motor (rotating means)
.

Claims (1)

[Claims] A pair of cleaning members made of flexible members that sandwich the charged wire is attached to a support member that automatically reciprocates along the charged wire, and the cleaning member pair cleans the outer periphery of the charged wire. An automatic cleaning device for a charger, characterized in that the cleaning device is provided with a rotation means for rotating the support member by a predetermined amount around the charging wire when the support member comes to at least one end side of the charging wire.