JP3199614B2 - Residual toner recovery device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a printer, a facsimile, and a copying machine, and more particularly to an improvement of a residual toner collecting apparatus using such an electrophotographic method.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus using an electrophotographic system is widely known, and includes charging, exposure, development, transfer,
An image is formed as a series of steps of cleaning. As shown in FIG. 3, the cleaning device of the image forming method scrapes off the untransferred residual toner adhered to the surface of the photoreceptor drum 10 with the cleaning blade 30 and the rubbing roller 40 in the cleaning device 20 and then removes the photosensitive drum. When the toner is conveyed in the direction orthogonal to the photosensitive drum 10 by the rotation force of the elliptical or polygonal conveyance roller 50 arranged on the upstream side in the rotation direction of the body drum shaft, and the residual toner is sent to the screw 60 disposed there, A configuration is known in which the residual toner is conveyed in the axial direction of the photosensitive drum by a screw 60 and the residual toner is fed into the toner container 8.

[0003]

However, in such a configuration, the scraped residual toner accumulates under the cleaning blade 30, leaks from a toner receiver disposed below the cleaning device 20, scatters downward, and contaminates the image. In some cases, printing failures such as the above may occur, and improvement in such a point has been desired. In particular, in a color electrophotographic apparatus using an intermediate transfer member, it is necessary to reliably eliminate toner leakage to the intermediate transfer member in order to enhance the gradation of an image. As described above, a device is conceivable in which a magnet or the like faces the photosensitive drum to reliably catch and forcibly discharge residual toner, but there are various problems to be solved such as a complicated device and an increase in manufacturing cost. Was.

The present invention has been made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide a low-cost cleaning apparatus that does not cause the scattering of residual toner.

[0005]

SUMMARY OF THE INVENTION In order to achieve the object of the present invention, the present invention removes residual toner on a photosensitive drum by rubbing the photosensitive drum with the photosensitive drum. A cleaning member, a transport roller disposed upstream of the photosensitive drum in the rotation direction and transporting the residual toner removed by the cleaning member, and a free end rubbing the transport roller to collect the residual toner. And a residual toner conveying plate arranged so as to be conveyable toward a screw member for conveying and collecting the toner. The conveying roller has an elliptical shape.
And a potential that is opposite to the charging potential of the residual toner is applied.

[0006] The transport roller may be formed of a conductive roller, and a voltage may be applied to the transport roller so that the potential of the transport roller is opposite to the charged potential of the residual toner.

Further, the transport roller may be made of a charge-series material that is charged to a potential opposite to that of the residual toner by frictional charging with the residual toner transport plate. In this case, it is preferable that the shape of the transport roller is an elliptical shape.

The residual toner scraped off by the blade is applied with a voltage or the residual toner floating is attracted by a transport roller frictionally charged with a transport plate, and the absorbed residual toner is transported by the transport roller. It is scraped off by the conveying member facing and is sent to the screw.
In this case, the elliptical conveyance roller increases the conveyance force more.

[0009]

1 and 2 show an embodiment of the present invention.
1 is a photosensitive drum, around which a charging device a, an exposure device b, a developing device c, and a transfer device d
Are disposed, the toner that has not been transferred by the transfer device d is cleaned by the cleaning device 2 through the charging, exposure, development, and transfer processes, and the process of forming an image again is repeated.

Reference numeral 3 denotes a cleaning blade, which is configured to be capable of contacting the photosensitive drum 1 for cleaning by a counter method. Reference numeral 4 denotes a rubbing roller, which is configured to scrape off toner that cannot be completely cleaned by the cleaning blade 3.

Reference numeral 5 denotes a transport roller, which is generally made of an insulating material. In particular, a material having a different charging potential and a different charging series from the residual toner is selected due to friction with a transport plate (residual toner transport plate) 7 described below. Thereby, the floating toner in the cleaning device 2 can be adsorbed to prevent toner scattering.

On the other hand, as shown in FIG. 3, an external electrode 5a may be connected to the conveying roller 5 so that the floating toner can be adsorbed. In this case, a conductive roller is used as the transport roller 5, and an elliptical shape can further impart a transport force.

Reference numeral 7 denotes a transport plate, which is configured so as to be in contact with the transport roller 5 so as to frictionally charge the transport roller 5 and to scrape off residual toner adsorbed on the transport roller 5. In addition, it has a function of conveying toner to the screw 6 described below. A film such as Mylar is used as a material of the transport plate 7, but is not limited thereto.

Reference numeral 6 denotes a screw. It is formed so as to extend in the axial direction, and conveys the residual toner sent from the conveying roller 5 in the axial direction and collects in the toner container 8.

With the above configuration, the residual toner completely scraped off from the photosensitive drum 1 by the cleaning blade 3 and the rubbing roller 4 is attracted to the transport roller 5 to which a voltage is applied or which is frictionally charged with the transport plate 7. The residual toner that has been further absorbed is scraped off by the transport plate 7 that is in contact with the transport roller 5 and is sent to the screw 6, and the screw 6 transports the residual toner in the axial direction of the photosensitive drum.
The toner is sent to the toner container 8.

[0016]

According to the present invention, as described above, there are provided a cleaning member, a screw member for collecting the residual toner into a collecting container, a conveying roller, and a residual toner conveying plate.
The transport roller and the residual toner transport plate are configured to be in contact with each other, and the transport roller is configured to have a potential opposite to that of the charged electrode of the residual toner. In addition to being eliminated, a toner recovery device with a simple configuration can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a residual toner collecting device according to the present invention.

FIG. 2 is a schematic diagram showing another embodiment of the present invention.

FIG. 3 is a schematic diagram showing a conventional residual toner collecting device.

[Explanation of symbols]

 1: photosensitive drum 2: cleaning device 3: cleaning blade (cleaning member) 4: rubbing roller 5: transport roller 6: screw (screw member) 7: residual toner transport plate 8: toner container

Claims (3)

(57) [Claims] A cleaning member disposed parallel to a photosensitive drum axis for removing residual toner on the photosensitive drum by rubbing with the photosensitive drum; and a cleaning member disposed upstream of a rotation direction of the photosensitive drum. A transport roller for transporting the residual toner removed by the cleaning member, and a residual toner transport arbitrarily arranged so as to be transported toward a screw member having a free end rubbing against the transport roller and transporting and collecting the residual toner to a collection container. A residual plate, wherein the transport roller has an elliptical shape and is configured to apply a potential that is opposite to a charging potential of the residual toner. 2. The apparatus according to claim 1, wherein said transport roller is formed of a conductive roller, and a voltage can be applied to said transport roller so that the potential of said transport roller is opposite to the charged potential of said residual toner. 2. The residual toner collecting device according to 1. 3. The residual roller according to claim 1, wherein said transport roller is made of a material of a charging series which is charged to a potential opposite to a charged potential of said residual toner by frictional charging with said residual toner transport plate. Toner collection device.