JPH06337589A - Toner recycling device - Google Patents

Abstract

PURPOSE:To provide a toner recycling device which prevents a large stain and a firefly-like stain on an image in the case of development using recovered toner. CONSTITUTION:The toner recycling device is equipped with: a cleaner 5 which removes and recovers residual toner on an image carrier 1; a toner carrying part 7 which carries the recovered toner to a recovered toner supplying part 84; and a recovered-toner supplying roller 83 which supplies the recovered toner, carried to the recovered toner supplying part 84, to a developing tank 21. A mesh 85 is provided in contact with the recovered toner supplying roller 83, on the side of the developing tank 21.

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 which collects residual toner on an image bearing member, conveys it to a developing device, and reuses the collected toner. .

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, development is performed by attaching toner to an electrostatic latent image formed on an image carrier, and the toner image is transferred to a transfer paper to make a copy. However, the toner of this toner image is not 100% transferred to the transfer paper, and some remains on the image carrier. The residual toner on the image bearing member was removed and collected by a cleaning device arranged close to the image bearing member, and the toner was conveyed again to the developing device for reuse (toner recycling). At this time, since the collected toner contains toner that has aggregated and solidified, it is necessary to select reusable toner. Therefore, for example, a method of collecting the toner that has passed through the cage-type filter element that is rotationally driven into the developing device (Japanese Patent Laid-Open No. 59-59).
No. 104683), a method of separating a large toner from usable toner by vibrating a mesh slightly larger than the toner particle size (Japanese Utility Model Laid-Open No. 55-128060), and collecting toner is passed through a plurality of meshes for classification. The method (Japanese Patent Application Laid-Open No. 54-116937) is proposed.

[0003]

However, in the above-mentioned conventional toner recycling method, it is not sufficient to select reusable toners, and the aggregated toner in the recovered toner is not enough to form solid areas or half areas on the transferred image. A more effective method has been desired in that large-scale stains and firefly-like stains do not appear in the tone portion. Therefore, the present invention solves the above-mentioned conventional problems, and can prevent large-grained stains and firefly-like stains from appearing on an image when the collected toner is used for development. It is an object to provide the toner recycling device of.

[0004]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a cleaning device for removing and recovering toner remaining on an image carrier, and a toner for conveying the recovered toner to a recovered toner replenishing section of a developing device. In a toner recycle device including a conveying unit and a collected toner replenishing roller that replenishes the collected toner conveyed to the collected toner replenishing unit to a developing tank of a developing device, the collected toner replenishing roller is brought into contact with the developing tank side. A mesh is provided, and the collected toner replenishing roller slides on the mesh to crush the agglomerated toner and replenish it to the developing tank.

[0005]

Therefore, the residual toner removed from the image carrier by the cleaning device is conveyed by the toner conveying portion to the collected toner replenishing portion of the developing device, and is further replenished to the developing tank by the collected toner replenishing roller. At this time,
When the collected toner replenishing roller is slidably rotated in contact with the mesh, all the toner that has aggregated and solidified in the collected toner is crushed, crushed, passed through the mesh, and drops into the developing tank. As a result, the collected toner can be reused even if it contains agglomerated and solidified toner, and the image is not contaminated.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a photosensitive drum 1 which is an image carrier
A developing device 2, a transfer charger 3 for charging when the toner image on the photosensitive drum 1 is transferred to the transfer paper, a separation charger 4 for charging when the transfer paper is separated from the photosensitive drum 1, A cleaning device 5 for cleaning the residual toner on the photosensitive drum 1 and a main charger 6 for charging the photosensitive drum 1 are arranged.
Toner transport unit 7 that transports the collected toner from the developing device 2 to the developing device 2
Are provided so as to connect them.

The developing device 2 includes a toner replenishing section 8 having a toner cartridge 81 for replenishing toner, a developing tank 21 which is a developing tank having stirring screws 22 and 23 and a developing roller 20, and a recycled toner hopper 84. A first replenishing roller 82 for supplying toner to the developing tank 21 is provided at the bottom of the toner replenishing unit 8, and a recovery for supplying toner to the developing tank 21 is provided at the bottom of the recycled toner hopper 84. A second replenishing roller 83, which is a toner replenishing roller, and a mesh 85, which is in contact with the second replenishing roller 83, are provided on the developing tank 21 side. The cross-sectional shape of the second supply roller 83 is, for example, as shown in FIG. 2A, is a regular octagon, and the contact portion with the mesh 85 is large.

Further, the cleaning device 5 has a toner recovery chamber 52, a first toner carrying coil 53, which is a screw type rotating body rotatably supported on the front and rear side plates of the cleaning device 5, and a cleaning blade 51. And
A second toner carrying coil 71 having the same shape as the first toner carrying coil 53 is provided in the toner carrying section 7.
The cleaning device 5, the toner conveying unit 7, the recycled toner hopper 84, the second supply roller 83, and the mesh 85 constitute a toner recycling device.

The second replenishing roller 83 and the first replenishing roller 82, and the first toner conveying coil 53 and the second toner conveying coil 71 are respectively connected to a driving mechanism (not shown) which is rotationally driven. In the above structure, the photoconductor drum 1 rotates clockwise, and the photoconductor drum 1 is charged and exposed (not shown) by the main charger 6.
An electrostatic latent image is formed on the electrostatic latent image, and toner is attached to the electrostatic latent image by the developing device 2 to form a toner image. Next, the transfer charger 3 and the separation charger 4 are used to form the photosensitive drum 1.
After the upper toner image is transferred onto the transfer paper, the toner image is fixed by a fixing device (not shown), and the paper is discharged.

On the other hand, after the transfer operation is completed, the photosensitive drum 1
The toner remaining on the top is cleaned by the cleaning blade 51, and the removed toner is collected in the toner collecting chamber 5
Recovered to 2. The toner T collected in the toner collecting chamber 52 is carried to the recycled toner hopper 84 of the developing device 2 by the first toner carrying coil 53 and the second toner carrying coil 71, and is supplied to the developing tank 21 again via the mesh 85. To be done.

Next, details of the operation of the toner recycling device will be described with reference to FIGS. 1 and 3. The collected toner T collected by the cleaning blade 51 of the cleaning device 5 falls into the toner collection chamber 52, and the first toner transport coil 53 rotates, so that the collected toner T moves to the front side or the back side of the photosensitive drum 1. The collected toner T transported to the front side or the back side of the photosensitive drum 1 is transported to the recycled toner hopper 84 of the developing device 2 by the rotation of the second toner transport coil 53 of the toner transport unit 7, and falls to the bottom thereof. To do. Then, the collected toner T is supplied to the developing tank 21 by the rotation of the second supply roller 83. At this time, the second supply roller 83 has a large contact portion with the mesh 85 as described above (see FIG. 2), this rotates in sliding contact with the mesh 85 (rotates while coming into contact with it), whereby the aggregated toner in the collected toner T is crushed and finely supplied to the developing tank 21. As shown in FIG. 4, the shape of the second supply roller 83 may be a brush roller 86 in which brush bristles are planted on the entire surface, and the toner that is efficiently aggregated and solidified by the friction between the brush and the mesh 85 is crushed. You can do it. The driving of the second supply roller 83 is performed by the first supply roller 8
It is performed in synchronization with the driving of No. 2.

In this embodiment, the recycled toner hopper 84 is provided separately from the toner replenishing section 8. However, the recycled toner hopper 84 is included in the toner replenishing section 8 in the same room, and the toner replenishing section 8 is provided in the toner replenishing section 8. The collected toner T may be directly guided. Further, the shape of the second supply roller 83 is not limited to the above embodiment, but may be other shapes.

[0013]

As described above, according to the present invention, a mesh is provided on the developing tank side in contact with the collected toner replenishing roller, and the collected toner replenishing roller is slidably rotated on the mesh to collect the aggregated toner. Since the toner is replenished to the developing tank while being crushed, the aggregated toner contained in the collected toner is completely crushed, and the developing tank (developing tank)
It is possible to stably obtain a good image even when the recovered toner is replenished to the developing device and recycled to the developing device for recycling.

[Brief description of drawings]

FIG. 1 is an overall schematic configuration diagram showing an embodiment of a toner recycling device of the present invention.

FIG. 2 is an explanatory diagram showing the shape of a collected toner supply roller.

FIG. 3 is a schematic configuration diagram showing a main part of a toner recycling device.

FIG. 4 is a perspective view showing a brush-shaped collected toner supply roller.

[Explanation of symbols]

 1 Image Carrier 2 Developing Device 5 Cleaning Device 7 Toner Conveying Section 21 Developing Tank 83 Collected Toner Replenishing Roller 84 Collected Toner Replenishing Section 85 Mesh

Claims (2)

[Claims] 1. A cleaning device for removing and recovering toner remaining on an image carrier, a toner transporting part for transporting the recovered toner to a recovered toner replenishing part of a developing device, and a recovery for transporting the recovered toner replenishing part. In a toner recycling device including a recovery toner replenishing roller that replenishes toner to a developing tank of a developing device, a mesh is provided on the side of the developing tank in contact with the recovery toner replenishing roller, and the recovery toner replenishing roller is provided on the mesh. On the other hand, the toner recycle device is characterized in that it slides and rotates to crush the agglomerated toner and supply it to the developing tank. 2. The toner recycling apparatus according to claim 1, wherein the recovered toner supply roller is a brush roller having bristles all over.