JPH1152788A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transport un-transferred toner into a developing device for re-use as a developer with a simple constitution, without providing a complicated mechanism such as a spiral screw connecting a cleaning device and the developing device. SOLUTION: In this device, un-transferred toner remaining on a photoreceptor 12 without being transferred to a transfer material is recovered by a cleaning device 26. This untrasferred toner is transported to a non-image area vicinity of the photoreceptor 12 by a paddle screw 30. Then, the un-transferred toner, carried on the non-image area of the photoreceptor 12, is lead to a developing device 18 in accordance with rotation of the photoreceptor 12. Moreover, the un-transferred toner on the photoreceptor 12 is captured by a wiping member 36 disposed so as to be held in contact with a surface of the photoreceptor 12, and is contained in a container 18b.

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,
In particular, the image forming apparatus is applied to, for example, a copying machine or a printer using an electrophotographic method, collects untransferred toner remaining on a photoconductor without being transferred to a transfer material, and reuses the untransferred toner as a developer. Related to the device.

[0002]

2. Description of the Related Art In a conventional image forming apparatus using an electrophotographic system, as shown in FIG. 4, an electrostatic latent image formed on the surface of a photoreceptor 1 is developed with toner by a developing device 2 and a transfer material 3 is developed. The transfer material 3 is charged from the back side of the photoconductor 1 to electrically transfer the toner image on the photoconductor 1 to the transfer material 3. At this time, the untransferred toner remaining on the photoconductor 1 without being transferred to the transfer material 3 is captured by the cleaning device 5 arranged downstream of the transfer device 4 in the rotation direction of the photoconductor 1. Then, the untransferred toner is stored in a predetermined container and then discarded together with the container.

[0003] On the other hand, Japanese Patent Application Laid-Open No. 7-253741 [G03G 21 /
10, 15/08], as shown in FIG. 5, a conveying unit (spiral screw) 6 for conveying the untransferred toner captured by the cleaning device 5 to the developing device 2 is provided, and The toner is reused as a developer.

[0004]

The former method is not preferable from the viewpoint of environmental protection because the container made of synthetic resin or the like is discarded together with the untransferred toner. In addition, since a space for installing the container is required, there is a problem that the entire apparatus becomes large. On the other hand, in the latter case, the untransferred toner can be regenerated and the running cost of the toner can be reduced. However, the conveying means 6 having a relatively large number of parts and requiring a large installation space must be provided. However, problems such as an increase in manufacturing cost and an increase in the size of the apparatus cannot be avoided.

SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide an image forming apparatus which can reuse collected untransferred toner as a developer with a simple structure.

[0006]

SUMMARY OF THE INVENTION The present invention includes a photosensitive member having a displaceable surface, on which an electrostatic latent image is formed, and a container for accommodating a developer. Developing means for developing the image, transfer means for transferring a developer image developed by applying a bias voltage having a polarity opposite to that of the developer to a transfer material, and cleaning for removing the developer remaining on the photoreceptor after transfer In the image forming apparatus provided with the means, the developer removed by the cleaning means is carried on the non-image area of the photoreceptor where the electrostatic latent image is not formed, and the developer is guided to the container according to the displacement of the surface. An image forming apparatus characterized by having the above configuration.

[0007]

The untransferred toner remaining on the surface of the photoreceptor without being transferred to the transfer material is captured by the cleaning means. The untransferred toner is guided to the vicinity of the non-image area of the photoconductor by the conveying unit, and then carried on the non-image area of the photoconductor. More specifically, a regulating member made of a conductive material is provided so as to contact a non-image area where an electrostatic latent image is not formed, and a bias voltage having the same polarity as the developer is applied to the regulating member. The non-transferred toner is electrostatically adhered to the non-image area of the photoreceptor. Further, if the non-image area is charged to the opposite polarity to that of the developer by the transfer means, the untransferred toner can be easily attached to the non-image area. The untransferred toner carried on the non-image area of the photoreceptor is guided to the developing unit in accordance with the displacement of the photoreceptor surface, is separated from the photoreceptor by the wiping member, and is stored in the container.

[0008]

According to the present invention, the recovered non-transferred toner is carried in the non-image area where the electrostatic latent image is not formed, that is, the surplus part which always occurs in the manufacturing method of the photoconductor, and Since the untransferred toner is guided to the developing unit in accordance with the displacement, a conveying unit such as a spiral screw for connecting the cleaning unit and the developing unit is unnecessary.
Therefore, the collected untransferred toner can be reused as the developer without increasing the manufacturing cost and increasing the size of the apparatus.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus 10 according to this embodiment shown in FIGS.
And the photoconductor 12 is, for example, an organic photoconductor (O
(PC) applied to a conductive substrate made of an aluminum tube. In this embodiment, a drum-shaped photoconductor is used, but a belt-shaped or plate-shaped photoconductor may be used.

A charger 14 is disposed above the photoconductor 12, and the surface of the photoconductor 12 is uniformly charged by the charger 14. Then, the original optical image formed by the exposure device 16 on the charged photoconductor 12 is incident via a mirror (not shown) or the like, and an electrostatic latent image is formed on the photoconductor 12. On the left side of the photoreceptor 12, a developing device 18 as a developing means is provided. The developing device 18 comes into contact with the surface of the photoreceptor 12 and contacts the photoreceptor 12 with a developer (hereinafter referred to as “toner”). ) Is provided. In addition, a container 18b in which toner is stored or stored is provided in association with the developing roller 18a.

A transfer device 20 as a transfer means is disposed below the photoconductor 12, and the transfer device 20 transfers the photoconductor 1 onto a transfer material 24 such as paper conveyed by conveyance rollers 22.
2 is electrostatically attracted to the toner image. That is, a bias voltage having a polarity opposite to that of the toner is applied to the transfer roller 22 from a power supply device (not shown), and the toner on the photoconductor 12 is electrically transferred to the transfer material. At this time, the untransferred toner remaining on the photoconductor 12 without being transferred to the transfer material 24 is captured by a cleaning device (cleaning unit) 26 disposed on the right side of the photoconductor 12. That is, the cleaning device 26 includes a cleaning blade 26a that elastically contacts the surface of the photoconductor 12, and the untransferred toner on the photoconductor 12 is collected in the container 26b by the cleaning blade 26a. Then, a static elimination lamp 28 disposed upstream of the charger 14 and downstream of the cleaning device 26 in the rotation direction of the photoconductor 12.
As a result, the residual charges on the photoconductor 12 are eliminated.

In such an image forming apparatus 10, a well-known electrophotographic process is repeatedly performed around the photoconductor 12. In this embodiment, the untransferred toner captured by the cleaning device 26 is carried on the non-image area (A) of the photoconductor 12 where no electrostatic latent image is formed, and is guided to the developing device 18. It is composed. That is, as shown in FIG. 3, a paddle screw 30 having a spiral paddle 30a that rotates around the axis O and is provided substantially at the center of the container 26b that stores the untransferred toner. The untransferred toner captured by the cleaning blade 26a and stored in the housing 26b by rotating the shaft 30 around the axis O is
The photoconductor 12 is conveyed to the vicinity of the non-image area (A). The non-image area (A) is a surplus part that always occurs in the manufacturing method of the photoconductor 12 in which the photosensitive layer is coated on a metal tube such as aluminum. In this embodiment, one of the outer peripheral surfaces of the photoconductor 12 is used. It is formed in an annular shape on the end side. That is, the paddle screw 30 conveys the untransferred toner to one end of the photoconductor 12.

The untransferred toner conveyed near the non-image area (A) of the photoconductor 12 is carried by the paddle screw 30 in the non-image area (A) of the photoconductor 12. That is, as can be clearly understood from FIGS.
2 so as to elastically contact the non-image area (A),
A film (regulating member) 32 in which a conductive material such as carbon black is mixed into an elastic body such as a urethane film.
And a bias voltage having the same polarity as that of the toner is applied to the film 32. The untransferred toner guided to the vicinity of the film 32 by the transport fins (not shown)
The thickness of the film 32 is regulated and thinned by the film 32, and a charge having the same polarity as that of the toner is given. As a result, the untransferred toner in the container 26a is
2 will be electrostatically attached.

Similarly, a film 34 made of an elastic material such as a urethane film is provided on the upstream side of the film 32 in the rotation direction of the photoconductor 12 so as to come into contact with the surface of the photoconductor 12. By
The untransferred toner captured by the cleaning blade 26a is prevented from leaking from the container 26b. The untransferred toner carried on the non-image area (A) of the photoconductor 12 is rotated by the rotation of the photoconductor 12 (displacement of the surface of the photoconductor).
Although it passes through the charge removing lamp 28 and the charger 14, the portion where the untransferred toner is carried corresponds to a region where the potential does not fluctuate, and is guided to the developing device 18 without being affected by the electrostatic.

The untransferred toner carried on the non-image area (A) of the photoreceptor 12 is collected in the developing device 18. That is, the developing device 18 includes a sponge-like wiping member 36 that comes into contact with the non-image area (A) of the photoconductor 12,
The untransferred toner on the photoconductor 12 is collected by the wiping member 36, and is stored in the storage body 18b. Further, on the same axis of the developing roller 18a, as shown in FIGS. 2 and 3, there is provided a transport fin 38 which rotates together with the developing roller 18a, and the transport fin 38 is captured by the wiping member 36. The untransferred toner is mixed with the unused toner in the container 18b. The wiping member 36 is not limited to a sponge-like member, and may be a plate (blade) formed of synthetic rubber, for example, or a brush-like member.

As described above, the untransferred toner collected by the cleaning device 26 is carried on a surplus portion (non-image area A) which always occurs in the manufacturing method of the photoconductor 12, and the photoconductor 12
Since the untransferred toner is conveyed to the developing device 18 in accordance with the displacement of the surface, the conveying device such as a spiral screw for connecting the cleaning device and the developing device is not provided as in the related art. The transfer toner can be guided to the developing device and reused. The non-image area (A) carrying the untransferred toner only needs to have a distance of about 5 mm in the axial center (longitudinal) direction of the photoconductor 12, so that the size of the apparatus and the manufacturing cost increase. Will not be invited.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is an illustrative view showing a configuration of a main part of the embodiment in FIG. 1;

FIG. 3 is a perspective view showing a configuration of a main part of the embodiment in FIG. 1;

FIG. 4 is an illustrative view showing a conventional technique;

FIG. 5 is an illustrative view showing a conventional technique;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus 12 ... Photoreceptor 18 ... Developing device 20 ... Transfer device 26 ... Cleaning device 30 ... Paddle screw 32 ... Film 36 ... Wiping member A ... Non-image area

Claims (6)

[Claims] A developing device for developing the electrostatic latent image with the developer, the photoconductor having a displaceable surface, an electrostatic latent image formed on the surface, and a housing housing a developer; Means for transferring a developer image developed by applying a bias voltage having a polarity opposite to that of the developer to a transfer material, and cleaning means for removing the developer remaining on the photoconductor after transfer. In the image forming apparatus, the developer removed by the cleaning unit is carried on a non-image area of the photoconductor on which the electrostatic latent image is not formed, and the developer is applied in accordance with the displacement of the surface. An image forming apparatus, wherein the image forming apparatus is guided to a container. 2. The image forming apparatus according to claim 1, further comprising a transport unit configured to transport the developer removed by the cleaning unit to a position near a non-image area of the photoconductor. 3. The image forming apparatus according to claim 1, further comprising a regulating member that regulates a thickness of the developer attached to the non-image area in contact with the non-image area. 4. An image forming apparatus according to claim 3, wherein said regulating member is formed of a conductive material, and a bias voltage having the same polarity as said developer is applied to said regulating member. 5. The image forming apparatus according to claim 1, further comprising a wiping member for wiping the developer adhered to the non-image area in contact with the non-image area, and storing the wiped developer in the housing. The image forming apparatus according to any one of the above. 6. The non-image area is charged by the transfer unit with a charge having a polarity opposite to that of the developer.
6. The image forming apparatus according to any one of claims 1 to 5,