JPH05289585A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent the scattering of toner, etc., by carrying the toner in a cleaning device without using a rotary driving means. CONSTITUTION:A toner receiving/carrying plate part A including places where residual toner scratched by a blade 3 is dropped, and almost horizontally formed, a vertical plate part B extending from the end part of the toner receiving/ carrying plate part A opposite to a photosensitive body 1, toward a vertical lower side, and a toner housing part bottom plate part C extending in a direction away from the photosensitive body 1, from the bottom end part of the vertical plate part B, are formed on the bottom wall part of a casing member 4 to which the blade 3 of the cleaning device 2 is attached. The toner receiving/ carrying plate part A is constituted of an electrostatic actuator member constituted in such a manner that plural electrodes 5b are buried in a stator 5a composed of an insulator. A prescribed voltage is applied to electrode terminals 6a, 6b, and 6c, so that driving force is generated by the mutual action of the charges of the toner and the driving electrodes 5b to carry the toner to a toner housing part side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile or a printer, and more specifically, a cleaning member for removing residual toner on an image carrier after transferring a toner image on a transfer material. The present invention relates to a cleaning device having.

[0002]

2. Description of the Related Art A conventional cleaning device has a rotating member for feeding the toner into a tank after cleaning the residual toner on the image carrier with a blade as a cleaning member. The rotary member is configured to receive drive from an external drive source. It is also known that the toner in the tank is transported to an external tank or a developing device by using a screw and a spring that are rotationally driven.

[0003]

However, according to the above construction, since the drive source is provided outside, the cleaning unit vibrates, and the blade contacting the photosensitive member vibrates and the cleaning unit vibrates. -There is a problem that the toner scatters from the inside of the cleaning tank to the outside due to the occurrence of defective cleaning and the rotation member. Further, in the case where a screw or the like which is driven to rotate is used as a means for conveying toner into an external tank or a developing device, the toner is scattered or the toner agglomerates to lock the screw, or the agglomerated toner However, there was a problem in that the toner could not be sufficiently agitated in the developing device, a charging failure occurred, and the background was stained.

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 capable of solving the above problems.

[0005]

To achieve the above object, the invention of claim 1 has a cleaning member having a cleaning member for removing the residual toner on the image carrier after transferring the toner image onto the transfer material. The apparatus is characterized in that an electrostatic actuator for conveying toner in a predetermined direction is provided on a casing wall that receives toner that has been removed from the image carrier by the cleaning member and dropped.

According to a second aspect of the present invention, in the cleaning device according to the first aspect, the cleaning member is supported by the casing of the cleaning device.

According to a third aspect of the present invention, in the cleaning device according to the first aspect, an electrostatic actuator that conveys the toner conveyed by the electrostatic actuator member to the developing device is provided. is there.

[0008]

In the present invention, the electrostatic actuator is used to convey the toner removed by the cleaning member and dropped from the image bearing member into the casing, or to convey the toner from the casing into the developing device. , Toner is conveyed without causing vibration or toner aggregation.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a cleaning device of an electrophotographic copying machine (hereinafter referred to as copying machine) which is an image forming apparatus will be described below. FIG. 1 is a schematic configuration diagram of a cleaning device according to this embodiment. In the figure, reference numeral 1 denotes a photoconductor drum which is an image carrier, and around the photoconductor drum 1, a charger, an exposure optical system, a developing device, a transfer / transfer device, which are not shown, for executing a well-known electrophotographic process. A separation device or the like is provided. The cleaning device 2 of the present embodiment is arranged so as to face the surface of the photoconductor 1 after the toner image obtained by visualizing the electrostatic latent image by the developing device is transferred to the transfer paper. .. The elastic blade 3 that abuts the photoconductor 1 and the photoconductor 1 that supports the blade 3
It has a casing member 4 forming a tank for storing the toner scraped from above. This casing member 4
The bottom wall portion of the toner receiving / conveying plate portion A includes a portion where the residual toner scraped off by the blade 3 falls and is formed substantially horizontally, and the photoreceptor 1 of the toner receiving / conveying plate portion A. Is a vertical plate portion B that extends vertically downward from the opposite end
And a toner accommodating portion bottom plate portion C extending from the lower end of the vertical plate portion in a direction away from the photoconductor 1. Then, the toner receiving / conveying plate portion A is used for the next electrostatic actuator.
Or a transfer member provided so that the conveying force of the electrostatic actuator member reaches the surface of the toner receiving / conveying plate portion A.

Now, the structure and operation of the electrostatic actuator member will be described in detail. As shown in FIG. 4A, this electrostatic actuator member is configured by embedding a plurality of electrodes (hereinafter referred to as drive electrodes) 5b in a stator 5a made of an insulator. This plurality of drive electrodes 5b
Each have an elongated strip shape in the axial direction of the photoconductor drum 1, and any of the first to third electrode terminals 6a, 6b, 6c in which adjacent electrodes are different from each other as shown in FIG. 4A. It is connected to the crab and forms three drive electrode groups. The arrangement pitch of the drive electrodes 5b may be set to, for example, about 10 to 20 μm so that the toner particles having a diameter of about 10 μm adhere to one drive electrode 5b in a line. The width and pitch in the same circumferential direction may be set to be large so that the toner particles adhere to one drive electrode in a plurality of rows. Then, by applying a voltage to these electrode terminals 6a, 6b, 6c as described later, a driving force is generated by the interaction between the electric charge of the toner and the electric charge of the drive electrode 5b, and the toner is conveyed.

Now, the principle of operation for carrying the toner by the electrostatic actuator member 3 will be described with reference to FIG. Here, it is assumed that the toner frictionally charged to + by the charging roller 4 is conveyed rightward in FIG. 4 on the electrostatic actuator member 3. As shown in FIG. 4A, when no voltage is applied to any of the electrode terminals 6a, 6b, 6c, there is no charge in the drive electrode 5b. On the other hand, the toner has a positive charge, but the stator 5
Since there is no charge on the side a, it is not controlled by the drive electrode 5b, and the toner is not transported. At this time, the toner is floating near the peripheral surface of the stator 5a or adheres to the stator 5a by some force. From this state, as shown in FIG. 4B, a positive voltage is applied to the first electrode terminal 6a, a negative voltage is applied to the second electrode terminal 6b, and a third voltage is applied.
0V is applied to the electrode terminal 6c. Then, the toner is attracted to the drive electrode to which a voltage having a polarity opposite to the charging polarity is applied. That is, + toner adheres to the surface of the developing roller on the drive electrode 5b to which −V is applied. At this time, the drive electrode 5b to which the + V voltage having the same polarity as the toner is applied and the drive electrode 5b to which the applied voltage is not applied
No toner is attracted to the top. Next, as shown in FIG. 4C, each applied voltage is applied to the second drive electrode group below the adhered toner by the same polarity + V as the toner.
To the third electrode group, which is adjacent to the second drive electrode in the toner conveying direction (right side in this example), has a polarity opposite to that of the toner by −V.
And to apply + V, which has the same polarity as the toner, to the first drive electrode group that is opposite to the toner transport direction of the second drive electrode. As a result, the electric charge of the toner and the electric charge of the drive electrode immediately below have the same polarity,
A repulsive force is generated and a levitation force is generated with respect to the toner, and the third drive electrode group in the toner transport direction changes from 0 to −V and has the same polarity as the toner. The electric charge of the upper left attracts the toner on the upper left, and the electric charge of the first drive electrode group opposite to the toner carrying direction has the same polarity as the toner, so the toner on the upper right is repelled and the right Directional driving force is generated. The levitation force reduces the friction between the toner and the surface of the developing roller, and the driving force by the electric charges causes the toner to move about one pitch of the driving electrode. Next, the voltage of the pattern for repulsing and driving the toner (FIG. 4C, FIG.
In order to shift (d) by one, each applied voltage is switched as shown in FIGS. 4 (e) and 4 (f). Thereafter, in the same manner, by applying the driving electrodes while shifting them one by one, the toner is continuously moved. Here, the switching of the applied voltage to each drive electrode group from FIG. 4 (b) to FIG. 4 (f) and after that is summarized in Table 1. The steps in the table are shown in FIG. 4B, the steps in FIGS. 4C and 4D, and the steps in FIG. 4E.
And (f) correspond. In the step, + V, −V, and + V are applied to each of the first to third drive electrode groups, and the voltage of the pattern for performing repulsion and driving of the toner is shifted from the step by one to the right in the toner transport direction. is there. After that, by repeating steps 1 to 3, the voltages of the patterns for repulsing and driving the toner are shifted one by one. (Hereafter, margin)

[Table 1] Note that, for example, in FIG. 4C (step), if the voltage applied to the third drive electrode group is made positive and the first drive electrode group is made negative, it is possible to drive in the opposite direction. When the toner to be conveyed has a negative charging polarity, a voltage having a polarity opposite to the above example may be used as the drive electrode applied voltage.

In the present embodiment, the residual toner scraped off from the surface of the photosensitive member 1 by the blade 3 and dropped onto the toner receiving / transporting plate portion A by the above-described transporting principle is used as the toner receiving / transporting plate portion. On A, the toner is conveyed to the toner accommodating section bottom plate C side and dropped on the toner accommodating section bottom plate C. Here, the toner that can be conveyed by the electrostatic actuator member includes both high resistance and medium resistance as long as they can be triboelectrically charged. However, in the case of the medium resistance toner, the toner is instantly attached to the surface of the developing roller above the drive electrode at the moment when the polarity of the voltage applied to the drive electrode is switched, and the charge of the drive electrode after the switching instantly If an electric charge having a polarity opposite to the triboelectric charge polarity is induced in the lower part of the toner, it may be attracted by the electric charge of the drive electrode and a sufficient repulsive force may not be obtained. Therefore, a resistor having a resistance that can obtain a sufficient repulsive force when the polarity of the voltage applied to the drive electrode is switched is used.

Next, a cleaning device according to another embodiment of the present invention will be described. FIG. 2 is a schematic configuration diagram thereof. The cleaning device 2 of the present embodiment is different from the cleaning device of FIG. 1 in that the toner accommodating portion bottom plate portion C of the casing 4 is also formed of the electrostatic actuator member, or the electrostatic actuator member has a conveying force. It is provided so as to extend to the surface of the toner receiving / conveying plate portion A. In this example, the electrostatic actuator member of the toner accommodating portion bottom plate portion C is arranged in the axial direction of the photosensitive drum 1 as shown by an arrow 7. It is configured to be conveyed to one side along with. Another toner storage tank (not shown) is connected to the end of the casing 4 on the downstream side in the toner conveying direction,
The toner conveyed by the electrostatic actuator member is stored in the toner storage tank.

Next, a cleaning device according to another embodiment of the present invention will be described. FIG. 3 is a schematic configuration diagram thereof. The cleaning device 2 of this embodiment is different from the cleaning device of FIG. 2 in that the electrostatic actuator member of the toner container bottom plate C of the casing 4 is replaced by the cleaning device 2
The toner collected from the photoconductor 1 is recycled to the inside of the developing device by extending the inside of the connecting portion 9 connecting the developing device 8 and the inside of the developing device 8. Arrow 10
Indicates the direction of toner conveyance from the inside of the connecting portion 9 into the inside of the developing device 8. The drive electrode 5b of the electrostatic actuator member in the recycling path is provided so as to be perpendicular to the toner carrying direction on the recycle path.

[0015]

According to the cleaning device of the first aspect of the present invention, there is no rotary member for conveying in a predetermined direction, for example, the inside of the toner accommodating portion or a drive source for driving the rotary member, and the electrostatic actuator means, that is, Since the toner is conveyed by changing the polarity of the voltage applied to the electrodes, it has an excellent effect of preventing the trouble of vibration due to external driving and the scattering of the toner by the rotating member.

In the cleaning device of claim 2,
Bracing a casing member having electrostatic actuator means.
Since the blade is attached, it is not affected by the vibration due to external driving, so there is no cleaning failure due to chattering of the blade due to the vibration of the cleaning device itself.
In addition, the device is simple and has an excellent effect of miniaturization.

In the cleaning device of claim 3,
An electrostatic actuator for transferring the toner in the tank to the outside.
Since the toner means is used, the toner does not aggregate when the toner is conveyed to the outside by the rotating member, and the toner does not block due to the toner sticking on the conveyance path (due to the aggregate toner). -Because aggregation does not occur, the chargeability of the toner entering the developing tank is improved, and there is an excellent effect that the background stain due to poor charging does not occur.

[Brief description of drawings]

FIG. 1 is a front view showing a schematic configuration of a cleaning device according to an embodiment.

FIG. 2 is a perspective view showing a schematic configuration of a cleaning device according to another embodiment.

FIG. 3 is a perspective view showing a schematic configuration of a copying machine that employs a cleaning device according to another embodiment.

4A to 4F are explanatory views of the operating principle of an electrostatic actuator member used in the cleaning device of each embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor drum 2 Cleaning device 3 Blade 4 Casing 5a Stator 5b Driving electrode 6a First electrode terminal 6b Second electrode terminal 6c Third electrode terminal 8 Developing device 9 Connecting part

Claims (3)

[Claims] 1. A cleaning device having a cleaning member for removing residual toner on an image carrier after transferring a toner image onto a transfer material, the toner being removed from the image carrier by the cleaning member and falling. A cleaning device, wherein an electrostatic actuator for conveying toner in a predetermined direction is provided on a casing wall. 2. The cleaning member is supported by a casing of the cleaning device.
Cleaning device. 3. The cleaning device according to claim 1, further comprising an electrostatic actuator that conveys the toner conveyed by the electrostatic actuator member to a developing device.