JPH0553456A - Cleaning device for transfer roller of electrophotographic device - Google Patents

Abstract

PURPOSE:To provide a cleaning device for a transfer roller which has few component parts, is economical, and has a small installation space on an electrophotographic device. CONSTITUTION:An electrostatic latent image is formed on the outer periphery of a photosensitive drum 1, a toner image is formed on the outer periphery of the photosensitive drum 1 by a developing device 3, the recording paper (p) is pinched between a transfer roller 4 and the photosensitive drum 1 and conveyed, voltage is applied to transfer the toner image on the photosensitive drum 1 to the recording paper (p) in an electrophotographic device, and a device 10 removing the toner stuck on the outer periphery of the transfer roller 4 is constituted of a toner removing member 13 brought into contact with the outer periphery of the transfer roller 4 to scrape off the toner stuck on the outer periphery of the transfer roller 4, an elastic member 12 fitted with the toner removing member 13 to press it to the transfer roller 4, and a toner receiving member 11 fitted with the elastic member 12 to receive the toner scraped from the transfer roller 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer roller cleaning device provided in an electrophotographic apparatus having a transfer roller.

[0002]

2. Description of the Related Art In an electrostatic type electrophotographic apparatus used in a copying machine, a facsimile machine, a laser printer, etc., a photosensitive drum is rotated so that an outer peripheral surface of the photosensitive drum is charged by a charging device and then exposed. An electrostatic latent image is formed on the outer peripheral surface of the photoconductor drum by a device, and then a electrostatic latent image on the photosensitive drum is developed by a developing device to form a toner image. The toner image is transferred onto recording paper.

In this electrophotographic apparatus, as a transfer device, a transfer roller is brought into direct contact with the back surface of the recording paper to sandwich and convey the recording paper between the photosensitive drum and the transfer roller, and the transfer roller has a polarity opposite to that of the toner. There is a roller system in which an electric charge is applied to perform transfer. The electrophotographic apparatus provided with this roller type transfer device is provided with a cleaning device for removing the toner adhering to the outer peripheral surface of the transfer roller.

For example, when a jam occurs in the recording paper conveying path of the electrophotographic apparatus, the position is located on the outer peripheral surface of the photosensitive drum between the contact point with the developing sleeve and the contact point with the transfer roller. The remaining toner image remains on the recording paper without being transferred. When the stopped recording paper is removed from the recording paper transport path and recording is started again, the photosensitive member is fed before the recording paper fed from the recording paper cassette reaches between the photosensitive drum and the transfer roller. When the drum and the transfer roller rotate, the outer peripheral surface of the photosensitive drum on which the toner image remains may come into contact with the outer peripheral surface of the transfer roller, and the toner may adhere to the outer peripheral surface of the transfer roller.

For this reason, the outer peripheral surface of the transfer roller is soiled with the toner, and when the recording paper is sandwiched between the photosensitive drum and the transfer roller and transferred, it adheres to the outer peripheral surface of the transfer roller. The remaining toner adheres to the back of the recording paper and the back of the recording paper becomes dirty. Therefore, it is necessary to remove the toner attached to the outer peripheral surface of the transfer roller.

Conventionally, as a transfer roller cleaning device, there is a system that mechanically removes toner adhering to the outer peripheral surface of the transfer roller. FIG. 5 shows a recording process section of an electrophotographic apparatus provided with a cleaning device of a type that mechanically removes toner. As a recording process unit, a charging device 2, an exposure device (not shown), a developing device 3, and a transfer roller 4 are provided around the photosensitive drum 1. The photoconductor drum 1 has a photoconductive layer on its outer peripheral surface, and is rotated in the direction of arrow A by a rotation driving device (not shown).
The charging device 2 is provided, for example, on the upper side of the photoconductor drum 1 so as to face the photoconductor drum 1, and is charged by corona discharge.
The outer peripheral surface of is charged. The exposure device is the charging device 2
On the other hand, the outer peripheral surface of the photosensitive drum 1 is selectively exposed by being provided in the latter stage of the recording process. The developing device 3 is provided on the latter stage side of the recording process with respect to the exposure device, and is provided with a tank 3a for storing toner and a rotatable developing sleeve 3b carrying a toner layer, and the developing sleeve 3b is supplied with a voltage having the same polarity as the toner. While applying, the developing sleeve 3b is rotated in the direction of arrow B to supply toner to the photosensitive drum 1 to form a toner image on the outer peripheral surface of the drum.

The transfer roller 4 is provided on the downstream side of the developing process with respect to the developing device 3, and is brought into contact with the outer peripheral surface of the photosensitive drum 1 by an urging means (not shown), such as a spring, and a rotary driving device (not shown). It is rotated in the direction of arrow C. The transfer roller 4 is conveyed together with the photoconductor drum 1 in the direction of the arrow D with the recording paper p interposed therebetween, and a voltage having a polarity opposite to that of the toner is applied by a circuit (not shown) to form a toner image on the outer peripheral surface of the photoconductor drum 1. Transfer to the recording paper p.

In order to continuously execute the recording process, the cleaner 21 for removing the toner remaining on the outer peripheral surface of the photosensitive drum 1 after the transfer and the photosensitive drum 1 before the charging.
A static elimination lamp 22 is provided to eliminate the potential on the outer peripheral surface of the.

A cleaning device for the transfer roller is provided below the transfer roller 4. This cleaning device is composed of a horizontally long plate member having a length corresponding to the transfer roller 4, a supporting member 5 arranged along the transfer roller 4, and a supporting member 5 provided along the transfer roller 4 for rotatably supporting the supporting member 5. A shaft 6, a toner removing member 7, which is attached to one end of the supporting member 5 and is made of an elastic material that comes into contact with the outer peripheral surface of the transfer roller 4 and scrapes off the toner that comes into contact with the outer peripheral surface,
The toner removing member 7 is provided along the axial direction of the transfer roller 4 and the spring 8 that applies a spring force in the direction of arrow E to the supporting member 5 so as to press the toner removing member 7 against the outer peripheral surface of the transfer roller 4. 4 is provided with a toner receiving member 9 for receiving the toner scraped off from the outer peripheral surface.

[0010]

As described above, since the conventional transfer roller cleaning device has many components, the cost is high and the size is large, and a large space is required to be provided inside the electrophotographic apparatus. There's a problem.

The present invention has been made in view of the above circumstances, and provides a cleaning device for a transfer roller of an electrophotographic apparatus, which has a small number of constituent parts and can reduce the space for installation inside the electrophotographic apparatus. It is intended.

[0012]

In order to achieve the above object, a cleaning device for a transfer roller of the present invention forms an electrostatic latent image on the outer peripheral surface of a photoconductor, and then a developing device forms the outer peripheral surface of the photoconductor. Of the electrostatic latent image to form a toner image, and then transfer the toner image on the outer peripheral surface of the photoconductor to the recording paper while conveying the recording paper while sandwiching the recording paper between the transfer roller and the photoconductor. In an electrophotographic apparatus, a device for removing toner adhering to the outer peripheral surface of the transfer roller, and a toner removing member that comes into contact with the outer peripheral surface of the transfer roller and scrapes off the toner adhering to the outer peripheral surface of the transfer roller, An elastic member for attaching the toner removing member and pressing it against the transfer roller, and a toner receiving member for attaching the elastic member and receiving the toner scraped off from the outer peripheral surface of the transfer roller are provided. And it is characterized in that formed by Bei.

[0013]

The constituent parts are only the toner receiving member, the elastic member and the toner removing member, and the number of parts is small. For this reason,
The cost of the cleaning device can be kept low and the size is small, and the space for installing the cleaning device inside the electrophotographic apparatus can be made smaller than in the conventional case.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a transfer roller cleaning device in an electrophotographic apparatus of the present invention will be described with reference to the drawings. An embodiment of the present invention will be described with reference to FIGS.

FIG. 2 shows a transfer roller cleaning device 10.
FIG. 3 is a diagram showing a state in which the electrophotographic apparatus is equipped with the. The electrophotographic apparatus shown in FIG. 2 is the same as the electrophotographic apparatus shown in FIG. 5 as a conventional example, and the same parts as those in FIG. That is, in FIG. 2, 1 is a photosensitive drum, 2 is a charging device, 3 is a developing device, and 4 is a transfer roller. The cleaning device 10 is provided below the transfer roller 4 like the conventional cleaning device. The cleaning device 10 has the configuration shown in FIG. In FIG. 1, 11 is a toner receiving member, 12 is an elastic member, and 13 is a toner removing member.

The toner receiving member 11 is made of, for example, metal and has a gutter shape having the same length in the axial direction as the transfer roller 4, and both ends thereof are closed. The toner receiving member 11 is arranged along the axial direction of the transfer roller 4 with its open portion facing upward, and is supported by a support member (not shown) provided in the main body of the electrophotographic apparatus.

The elastic member 12 is made of, for example, a thin metal plate having elasticity and has the same length as the transfer roller 4 in the axial direction. The elastic member 12 is arranged in the opening portion of the toner receiving member 11 along the length direction thereof, the lower edge thereof is in contact with the side edge of the toner receiving member 11, and there is an interval in the length direction of the toner receiving member 11. It is fixed to the side edge of the toner receiving member 11 by the screws 14 at a plurality of points. In this state, the elastic member 12 exerts an elastic force toward the outer peripheral surface of the transfer roller 4.

The toner removing member 13 is made of an elastic material such as rubber as a material capable of scraping off the toner adhering to the outer peripheral surface of the transfer roller 4 without damaging the outer peripheral surface. Specifically, it is made of silicon rubber or urethane rubber and has a blade shape attached to the upper edge of the elastic member 12. Then, the toner removing member 13 described above causes the transfer roller 4 to move by the elastic force of the elastic member 12.
Is pressed against the outer peripheral surface of the entire axial direction thereof.

The area and angle of the portion where the toner removing member 13 contacts the transfer roller 4 are set so that the toner adhering to the outer peripheral surface of the transfer roller 4 can be efficiently scraped off.

The cleaning device 1 thus constructed
0 is located below the transfer roller 4 inside the main body of the electrophotographic apparatus and is detachably mounted. Specifically, the toner receiving member 11 is detachably supported by a supporting member provided inside the main body of the electrophotographic apparatus. The toner removing member 13 attached to the elastic member 12 is pressed against and contacts the outer peripheral surface of the transfer roller 4. Therefore, when the transfer roller 4 rotates when the electrophotographic apparatus performs recording, the toner removing member 13 comes into sliding contact with the transfer roller 4.

For example, as described in the section "Prior Art", the outer peripheral surface of the photosensitive drum 1 on which the toner image remains remains in contact with the outer peripheral surface of the transfer roller 4, and the toner adheres to the outer peripheral surface of the transfer roller 4. In this case, the toner removing member 13 that is in sliding contact with the outer peripheral surface of the transfer roller 4 scrapes off the toner attached to the outer peripheral surface of the transfer roller 4 over the entire axial direction of the transfer roller 4. Toner receiving member 11 located below the transfer roller 4
Receives the toner scraped off by the transfer roller 4 over the entire axial direction of the transfer roller 4.

In the cleaning device 10 of this embodiment,
Since the elastic member 12 is directly attached to the toner receiving member 11, the elastic member 12 is provided separately from the toner receiving member 11 with only the toner receiving member 11, the elastic member 12 and the toner removing member 13 as the constituent parts. Compared with the case, the number of parts is small. Therefore, the cleaning device 10
The cost can be kept low and the size can be reduced, and the space for installing the cleaning device 10 inside the electrophotographic apparatus is smaller than the conventional one.

By the way, the toner removing member 13 continues to be in sliding contact with the outer peripheral surface of the transfer roller 4, so that the toner removing member 13 is worn and its thickness is reduced. Therefore, as the time when the toner removing member 13 slides on the outer peripheral surface of the transfer roller 4 accumulates, it becomes gradually difficult to scrape off the toner adhering to the outer peripheral surface of the transfer roller 4 due to abrasion. In this state, the toner removing member 13 becomes unusable and needs to be replaced.

In this embodiment, since the elastic member 12 to which the toner removing member 13 is attached is attached to the toner receiving member 11, the toner receiving member 11 is removed from the supporting member that supports the toner receiving member 11. 13 can be integrally removed. And screw 1
By removing 4, the toner removing member 13 can be easily replaced. FIG. 3 shows another embodiment.
3, the same parts as those in FIG. 1 are designated by the same reference numerals.

In this embodiment, the toner removing member 15 is replaced by a blade-shaped member and a kamaboko-shaped member is used as the elastic member 1.
It is attached to No. 2 by adhesion. Also in this embodiment, the area and the angle of the portion of the toner removing member 15 in contact with the transfer roller 4 are set so that the toner attached to the outer peripheral surface of the transfer roller 4 can be efficiently scraped off.

FIG. 4 shows another different embodiment. 4, the same parts as those in FIG. 1 are designated by the same reference numerals. In this embodiment, the side wall of the toner receiving member 16 is extended and used as the elastic member 17, and the toner removing member 13 is attached to this portion.

[0027]

As described above, according to the cleaning device for the transfer roller of the electrophotographic apparatus of the present invention, the toner removing member for contacting the outer peripheral surface of the transfer roller and scraping off the toner adhering to the outer peripheral surface of the transfer roller. Since it is composed of a few parts such as an elastic member that attaches this toner removing member and presses it against the transfer roller, and a toner receiving member that attaches this elastic member and receives the toner scraped off from the outer peripheral surface of the transfer roller, It is possible to obtain the effects that the apparatus cost is low, the economy is good, the apparatus is small, and the space to be provided for the electrophotographic apparatus is small.

[Brief description of drawings]

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

FIG. 2 is a diagram showing a schematic configuration of an electrophotographic apparatus provided with the cleaning device of the embodiment.

FIG. 3 is a diagram showing another embodiment of the cleaning device.

FIG. 4 is a perspective view showing another embodiment of the cleaning device.

FIG. 5 is a diagram showing a schematic configuration of an electrophotographic apparatus including a conventional cleaning device.

[Explanation of symbols]

11 ... Toner receiving member, 12 ... Elastic member, 13 ... Toner removing member.

Claims (1)

[Claims] 1. An electrostatic latent image is formed on an outer peripheral surface of a photoconductor, and then a developing device develops the electrostatic latent image of the photoconductor to form a toner image. Then, a transfer roller and the photoconductor form the image. In an electrophotographic apparatus of a type in which a toner image on the outer peripheral surface of the photoconductor is transferred to the recording paper while being conveyed while sandwiching the recording paper, a device for removing toner adhering to the transfer roller, A toner removing member that comes into contact with the outer peripheral surface and scrapes off the toner adhering to the outer peripheral surface of the transfer roller; an elastic member that attaches the toner removing member and presses the transfer roller; A cleaning device for a transfer roller of an electrophotographic apparatus, comprising: a toner receiving member for receiving the toner scraped off from the outer peripheral surface.