JPH04329582A - Method and device for cleaning latent image carrier - Google Patents

Abstract

PURPOSE:To provide a cleaning device where a cleaining blade can be brought into contact/uncontact with a photosensitive body without using a self-holding type or great capacity solenoid as a cleaning-blade driving solenoid. CONSTITUTION:A rack bar 2 which is attracted when a solenoid 1 is energized is connected to a spring 3. A gear 4 which turns by the movement of the rack bar 2 is provided on an axis 5. A cam 8 for driving displacing of the claning blade 11 is integrally provided on the same axis. A unidirectional rotary clutch 13 is provided between the gear 4 and the shaft 5. The clutch 13 is used for not transmitting the turning of the gear 4 to the shaft 5 in order to maintain the abutting condition of the cleaning blade 11 enven when the solenoid 1 is turned off.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for cleaning a latent image carrier.

0002

2. Description of the Related Art In image forming apparatuses such as electronic copying machines, printers, and facsimile machines, an electrostatic latent image is formed on the surface of a latent image carrier, and this latent image is visualized as a toner image.
In so-called electrophotographic or electrostatic recording systems, after the toner image is transferred to a transfer material such as plain paper, toner remains on the surface of the latent image carrier, so it is necessary to clean it. I have to.

Generally, for such cleaning, a cleaning blade made of an elastic material such as rubber is brought into contact with the surface of the latent image carrier, and the residual toner is scraped off with the cleaning blade. Cleaning equipment is often used.

When the image forming apparatus is, for example, an electronic copying machine, if the cleaning blade is left in contact with a latent image carrier such as a photoreceptor, the edge of the cleaning blade may be damaged. To avoid deformation, excessive abrasion of the edges, or shortening of the life of the photoconductive layer on the surface of the photoreceptor, it is separated from the latent image carrier after the copying operation is completed. .

Solenoids are commonly used to bring the cleaning blade into contact with or away from the photoreceptor, but normally, when the solenoid is energized, When the cleaning blade is brought into contact with the surface of the photoreceptor and the copying operation is completed, the excitation of the solenoid is released and the cleaning blade is separated from the photoreceptor by the force of a spring or the like.

In such a configuration, the solenoid remains energized while the cleaning blade is in contact with the photoconductor, which increases power consumption and also causes the solenoid itself to become hot. , which also causes the cabin temperature to rise. The higher the temperature of the solenoid, the weaker its suction force becomes, so in order to obtain a predetermined pressing force for the cleaning blade, it is necessary to design a solenoid with a large capacity that takes this into consideration.

[0007] Therefore, a technique disclosed in Japanese Unexamined Patent Publication No. 1-210984 has been proposed in which a self-holding solenoid is used to drive the cleaning blade. In a cleaning device that uses such a self-holding solenoid, during suction (when energized),
At the time of return (when de-energizing), it is only necessary to momentarily flow current through the solenoid, which has the advantage of reducing power consumption and not causing a rise in temperature.

However, when an instantaneous current is applied to a self-holding cleaning blade, there is a
The direction in which the current flows must be changed, which tends to make the circuit system for controlling the solenoid etc. complicated. Furthermore, since the self-holding solenoid itself is expensive, it also causes an increase in the cost of the image forming apparatus.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for cleaning a latent image carrier, which eliminates the above-mentioned conventional drawbacks.

Another object of the invention is to provide a cleaning device for a latent image carrier that eliminates the above-mentioned conventional drawbacks.

[0011]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for cleaning the latent image by displacing a cleaning blade located at a distance from the latent image carrier to a position where it comes into contact with the latent image carrier. In a method for cleaning a latent image carrier in which toner remaining on the latent image carrier is cleaned by a cleaning blade after the toner image on the carrier is transferred to a transfer material, a cleaning blade for driving the displacement of the cleaning blade is used. By energizing the solenoid, a moving member connected to the solenoid is moved, and a rotating member that rotates in conjunction with this movement is rotated in one direction, thereby displacing the cleaning blade through a one-way rotation clutch. The member is driven to displace the cleaning blade from the separated position to the contact position, and after this displacement, the excitation of the solenoid is released, and after this release, the movable member is moved back in the opposite direction by the biasing member, and this The rotating member is idly rotated in a direction opposite to the one direction by the action of a one-way rotation clutch so that the drive transmission relationship from the rotating member to the cleaning blade displacement imparting member is severed when returning to the movement. This paper proposes a cleaning method for a latent image carrier.

Another aspect of the invention is that the toner image on the latent image carrier is movable between a position in contact with the latent image carrier and a position away from the latent image carrier, and the toner image on the latent image carrier is moved at the contact position. In a latent image carrier cleaning device equipped with a cleaning blade that cleans toner remaining on the latent image carrier after being transferred to a transfer material, the cleaning blade is excited to displace the cleaning blade from a remote position to a contact position. ,
A solenoid that is de-energized after the displacement, a moving member that is moved by the excitation, a rotating member that is rotated in one direction in conjunction with the movement of this moving member, and a rotation of this rotating member. a cleaning blade displacement imparting member that displaces and drives the cleaning blade from a separated position to a contact position in conjunction with the movement of the cleaning blade; a biasing member that moves and returns the moving member in the opposite direction after the solenoid is deenergized; and a cleaning blade that returns the cleaning blade to the contact position. When displacing the cleaning blade, the drive transmission relationship from the rotating member to the cleaning blade displacement imparting member is linked, and when the movable member returns to movement, the drive transmission relationship is severed and the rotating member is moved in the opposite direction to the one direction. A cleaning device for a latent image carrier is proposed, which is provided with a one-way rotational clutch for causing idle rotation.

The moving member is a rack rod, the rotating member is a gear that meshes with the rack rod, the cleaning blade displacement member is a cam that rotates by the rotation of the gear, and the one-way rotation clutch is It is effective to use a one-way rotational clutch interposed between the gear and a shaft provided with a gear and a cam, respectively.

[0014]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 100 indicates a drum-shaped photoreceptor, which is an example of the structure of a latent image carrier, and is rotatably driven in the direction of arrow a by a drive device (not shown). During this rotation, as is already well known, charging, exposure, development, etc. are performed in sequence, and a toner image is formed on the surface of the photoreceptor 100. This toner image is transferred to a transfer material (not shown) such as plain paper.

After such transfer, toner that did not contribute to the transfer remains on the surface of the photoreceptor 100, but this residual toner is scraped off by a cleaning blade 11. It is.

The cleaning blade 11 is made of an elastic material such as rubber, and has a long strip shape in the axial direction of the photoreceptor 100. Attached to the free end. At this time, the cleaning blade 11 may be immovably fixed to the blade mounting member 10, or the longitudinal center portion of the cleaning blade 11 may be fixed to the blade mounting member 10.
The blade 11 may be pivotally attached to the center of the blade 11 so that the blade 11 can swing around the center thereof.

Reference numeral 1 designates a solenoid for driving the displacement of the cleaning blade, and one end of a moving member 2 is connected to this plunger 1A. A rotating member 4 is provided on a shaft 5 that is horizontally suspended so as to be parallel to the axis of the photoreceptor 100 .

As will be described later, the cleaning blade 11 has a position remote from the photoreceptor 100 and a position separated from the photoreceptor 100.
It is movable to each position between the contact position and the contact position, and the residual toner is cleaned as described above at the contact position.

[0020] Now, returning to the original explanation, solenoid 1
is energized to displace the cleaning blade 11 from the remote position to the contact position, and the excitation is immediately released after the displacement. The moving member 2 is
The excitation causes it to move in the excitation direction. The rotating member 4 is rotated in one direction in conjunction with the movement of the moving member 2.

In this embodiment, the movable member 2 is located in the rack section 2A.
The rotating member 4 is a gear that meshes with the rack portion 2A. Reference numeral 8 denotes a cleaning blade displacement imparting member for displacing and driving the cleaning blade 11 from the separated position to the contact position as the gear 4 rotates. The applying member 8 is a cam that rotates together with the gear 4.

Such a cam 8 is provided on the shaft 5 together with the first gear 4, and the latter cam 8 is integrally fixed to the shaft 5. Further, a one-way rotation clutch (one-way clutch) 13 is interposed between the gear 4 and the shaft 5.

After de-energizing the solenoid 1, the rack rod 2
In this example, a biasing member for moving and returning the motor in a direction opposite to the excitation direction is hung between the stationary pin 14 and the rack rod 2 as a tension spring 3 shown by reference numeral 3.

Here, FIG. 1 shows a cleaning blade 1
1 is shown in contact with the photoconductor 100, but when the cleaning blade 11 is separated from the photoconductor 100, the solenoid 1 is not energized and the rack rod 2 is in contact with the tension elasticity of the spring 3. It is placed above the position shown in the figure. Further, the cam 8 is located at a position a half turn from the position shown in the figure, and its short diameter circumferential surface is in contact with the projecting portion 10a of the blade attachment member 10.

Now, assuming that the image forming apparatus is an electronic copying machine, when a print button (not shown) is pressed to start a copying operation, the solenoid 1 is energized by being energized. There is. With this excitation, the plunger 1A is connected to the rack rod 2.
and move it in the direction of the arrow.

With this movement, the gear 4 meshing with the rack portion 2A is rotated in one direction. That is, arrow b
It can be rotated in the direction. At this time, the one-way rotation clutch 13 connects the drive transmission relationship between the gear 4 and the shaft 5, and rotates the latter shaft 5 integrally with the gear 4 in the same direction as the gear 4. Along with this, the left cam 8 also rotates together, and at this time, the cam 8 pushes and moves the overhanging portion 10a to rotate the blade mounting member 10 around the pivot shaft 12 in the direction of arrow c.

The cam 8 has a long-diameter circumferential surface 8a cut flat as shown in the figure, and this portion forms an overhanging portion 10.
The cleaning blade 11 comes into contact with the surface of the photoreceptor 100 in a state where it is in contact with a. The blade attachment member 10 has a spring 9 suspended between it and a stationary member (not shown).
When the cleaning blade 11 is biased to rotate in a direction away from the photoreceptor 100, and when the blade mounting member 10 rotates in the direction in which the cleaning blade 11 comes into contact with the photoreceptor, such rotation is caused by the force of the spring. It is carried out against the elastic force of 9.

The cam 8 thus serves as a cam for pressurizing the cleaning blade. This cam 8 is
As described above, since the long diameter circumferential surface portion 8a is cut, when this cut portion is in contact with the overhanging portion 10a, the blade mounting member 10 does not move around the pivot 12, and the cleaning blade 10 is held in contact with the photoreceptor 100 with a stable pressing force.

Here, a cam 6 is fixedly provided on the shaft 5 to detect the contact state of the cleaning blade 11, and when the cleaning blade 11 contacts the photoreceptor 100, The long-diameter circumferential surface of the detection cam 6, which rotates integrally with the shaft 5, pushes the actuator 7a of the contact detection switch 7, which is arranged in a mutual positional relationship with the cam, thereby turning off the switch 7. When this switch is turned off, the energization to the solenoid 1 is turned off and its excitation is released, and as a result, the rack rod 2 is moved in the direction away from the solenoid 1 due to the elasticity of the spring 3. It will be done. That is, the rack rod 2 is moved back to the position before the solenoid 1 was energized.

At this time, the gear 4 meshing with the rack rod 2 is rotated in the direction opposite to the direction of arrow b. At this time, since the one-way rotation clutch 13 is installed so that the drive transmission relationship between the gear 4 and the shaft 5 is broken, the gear 1
3 only idles in that direction, the shaft 5 does not rotate, the position of the cam 8 does not change, and the cleaning blade 11 is held in contact with the photoreceptor 100.

After the copying operation is completed and a certain period of time has elapsed, current is again applied to the solenoid 1, and the solenoid is energized. Accordingly, the rack rod 2, which had returned to a position above the position shown in the figure, is pulled toward the solenoid 1, and at this time, the gear 4 is rotated in the direction of arrow b. Then, the shaft 5 rotates in the same direction via the one-way rotation clutch 13, and the cam 8 rotates together with this shaft.
The cleaning blade 11 is placed at a remote position away from the photoreceptor 100 with the cam 8 turning exactly half a turn from the position shown in the figure. In this way, the cleaning blade 11 is separated from the photoreceptor 100.

FIG. 2 is a timing chart corresponding to this embodiment, and in this chart, the drive motor is a motor that serves as a drive source for rotationally driving the photoreceptor 100 and the like. Further, the detection switch is a switch 7 that is turned on and off by the detection cam 6 shown in FIG. In addition, when the cleaning blade pressure is turned on, it means that the cleaning blade 11 comes into contact with the photoreceptor 100, and when it is turned off, it means that it is separated from the photoreceptor 100.

As understood from the above explanation, the cam 8
constitutes an example of the configuration of a cleaning blade displacement imparting member for displacing and driving the cleaning blade 11 from the separated position to the contact position, and the one-way rotation clutch 13 displaces the cleaning blade 11 to the contact position. When the cleaning blade is moved, from the gear 4, which is an example of a rotating member, to the cam 8, which is an example of a cleaning blade displacement member.
When the rack rod 2, which is an example of a configuration of a moving member, returns to movement, the drive transmission relationship is severed, and the gear 4, which is an example of a configuration of a rotating member, is connected to the solenoid 1.
The rotation direction is opposite to the direction of rotation during excitation.

[0034] In this way, the one-way rotation clutch 13 is
It has an important function of idling the gear 4, and due to this function, even if the solenoid 1 is de-energized, the shaft 5 will not rotate, and the cam 8 will not rotate unless the solenoid 1 is energized next.
It continues to be held in the position shown in FIG.

According to such a cleaning method, the solenoid is not continuously energized during the copying operation, so power consumption is reduced and the temperature does not rise. If the solenoid does not reach high temperatures, it will be possible to suppress the rise in internal temperature of the machine. Also, when the solenoid becomes hot, this suction force weakens, so it is necessary to use a solenoid with a corresponding capacity, but with this cleaning method, it is not necessary to use a solenoid with a large capacity. . Furthermore, since there is no need to use an expensive self-holding type solenoid, the cost of the image forming apparatus can be reduced accordingly. The cleaning device of this example can achieve these various functions with a simple configuration.

[0036]

According to the cleaning method according to claim 1, the power consumption for operating the solenoid can be minimized, and the solenoid does not become high temperature, so that it is possible to form an image. One factor that increases the temperature inside the device can be eliminated. Furthermore, there is no need to use a relatively expensive self-holding solenoid to drive the cleaning blade, and an ordinary low-cost solenoid can be used, making it possible to reduce the cost of the image forming device. Become.

According to the cleaning device according to the second aspect, the power consumption for operating the solenoid can be minimized, and since the solenoid does not become high temperature, the inside of the image forming apparatus can be One factor that increases temperature can be cut off. Furthermore, there is no need to use a relatively expensive self-holding solenoid to drive the cleaning blade, and an ordinary low-cost solenoid can be used, making it possible to reduce the cost of the image forming device. Become. Such effects can be obtained with a simple configuration.

According to the cleaning method or device according to claims 3 and 4, since the gear rotates in precise synchronization with the movement of the rack rod, the position of the cam for displacing the cleaning blade is accurately determined, and the position of the cam for displacing the cleaning blade is accurately determined. The contact force can be set precisely.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a cleaning device according to an embodiment of the present invention.

FIG. 2 is a timing chart corresponding to the above embodiment.

[Explanation of symbols]

1 Solenoid 2 Rack rod as a moving member 3 Spring as a biasing member 4 Gear as a rotating member 8 Cam 11 as a cleaning blade displacement member Cleaning blade 13 One-way rotation clutch

Claims (4)

[Claims] Claim 1: A cleaning blade located at a distance from the latent image carrier is moved to a position where it comes into contact with the latent image carrier, and after the toner image on the latent image carrier is transferred to the transfer material, the cleaning blade is removed from the latent image carrier. In a method for cleaning a latent image carrier in which toner remaining on the image carrier is cleaned by a cleaning blade, a moving member connected to the solenoid is moved by excitation of a solenoid for driving the displacement of the cleaning blade. By rotating the rotating member that rotates in conjunction with this movement in one direction, the cleaning blade displacement imparting member is driven via the one-way rotation clutch, and the cleaning blade is brought into contact with the cleaning blade from the remote position. position, and after this displacement, the excitation of the solenoid is released, and after this release, the movable member is moved back in the opposite direction by the biasing member, and at the time of this return to movement, the cleaning blade displacement imparting member is removed from the rotating member. A method of cleaning a latent image carrier, wherein the rotary member is idly rotated in a direction opposite to the one direction by the action of a one-way rotation clutch so that a drive transmission relationship between the rotation member and the rotation member is severed. 2. It is movable between a position in contact with the latent image carrier and a position away from the latent image carrier, and in the contact position, the toner image on the latent image carrier is transferred to the transfer material. In a latent image carrier cleaning device equipped with a cleaning blade that cleans toner remaining on the latent image carrier after cleaning, the cleaning blade is excited to displace the toner from the separation position to the contact position, and after the displacement, ,
A solenoid that is de-energized, a moving member that is moved by the excitation, a rotating member that is rotated in one direction in conjunction with the movement of the moving member, and a rotating member that is rotated in one direction in conjunction with the rotation of the rotating member. a cleaning blade displacement imparting member for displacing and driving the cleaning blade from a separated position to a contact position; a biasing member for moving and returning the movable member in the opposite direction after the solenoid is deenergized; and when displacing the cleaning blade to the contact position; A drive transmission relationship from the rotating member to the cleaning blade displacement imparting member is linked, and when the movable member returns to movement, the drive transmission relationship is severed and the rotating member is idled in the opposite direction to the one direction. A cleaning device for a latent image carrier, comprising a one-way rotation clutch. 3. The movable member is a rack rod, the rotating member is a gear that engages with the rack rod, the cleaning blade displacement member is a cam that rotates by rotation of the gear, and the one-way rotation clutch comprises: 2. The method of cleaning a latent image carrier according to claim 1, wherein the cleaning method is a one-way rotating clutch interposed between a shaft provided with a gear and a cam, and the gear. 4. The movable member is a rack rod, the rotating member is a gear that meshes with the rack rod, the cleaning blade displacement member is a cam that rotates by rotation of the gear, and the one-way rotation clutch comprises: 3. The cleaning device for a latent image carrier according to claim 2, wherein the device is a one-way rotating clutch interposed between the gear and a shaft provided with a gear and a cam, respectively.