JP2509433Y2 - Electrophotographic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention provides a developing device that electrostatically attracts toner to the surface of a photoreceptor to visualize an electrostatic latent image, and a toner image thus visualized. The present invention relates to an electrophotographic apparatus including a transfer separation device that transfers a transfer paper.

2. Description of the Related Art As miniaturization of copiers, facsimiles, printers, etc. has progressed, each device inside the machine, such as a developing device, a photoconductor,
The layout of the transfer separation device is also changing. Conventionally, belts that use a belt-shaped photoreceptor are stretched horizontally with respect to the machine body, but as the size of the entire machine is reduced, the photoreceptor belt may be laid out diagonally from the conventional horizontal direction. I came. When the transfer paper is transferred while being vertically conveyed in such a layout, when the transfer paper is jammed, the paper may be sandwiched between the photoconductor and the transfer separation device. In order to remove this transfer paper, a method of releasing the transfer separation device is adopted. However, the transfer paper to be removed may fall obliquely downward along the surface of the photoconductor at the moment when the transfer separation device is released. Especially when a small size transfer paper drops, you will not notice that it has fallen, and you will not notice the problem until you operate the machine without noticing it.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention An object of the present invention is to solve the above-mentioned problems in an electrophotographic apparatus.

Means for Solving the Problems According to the present invention, a thin plate-shaped guide member having elasticity is provided in the vicinity of a surface of a photoconductor between a developing device and a transfer separation device so as to face the photoconductor surface. Will be solved by.

Further, the present invention proposes that the guide member includes a base portion made of polyester film and a tip portion made of polyurethane rubber which is close to the surface of the photosensitive member.

The present invention also proposes disposing a plurality of the guide members.

According to the present invention, by arranging the elastic thin plate-like guide member in the vicinity of the surface of the photoconductor so as to face it, it is possible to prevent the jammed transfer paper from dropping downward along the surface of the photoconductor.

EXAMPLE An outline of the copying machine shown in FIG. 1 will be described. A document sent by the automatic document feeder 1 is an illumination lamp 2 having a reflecting plate 2a, a first mirror 3, an imaging lens 4, and a second mirror. It is projected onto the photoconductor belt 6 via 5. Therefore, an electrostatic latent image is formed on the surface of the photoconductor belt 6 that has been uniformly charged by the main charger 7, and the electrostatic latent image on the surface of the photoconductor belt 6 is developed by the developing unit 8 to form a toner image. Created. This toner image is transferred to the transfer paper sent from the paper feeding device 9 through the registration roller pair 21 and transferred to the transfer separation unit.
20 is transferred by the electric field of the transfer charger unit 10. The transfer paper on which the toner image is transferred is separated from the photoconductor belt 6 by the separation charger unit 11 of the transfer separation unit unit 20, and the tip of the transfer paper is guided by the guide claw 12 to the transport belt 13 of the transfer separation unit unit. Then, while being sucked toward the conveyor belt 13 by the air suction unit 14, it is sent to the fixing unit 15 located above, where the toner image is fixed by the fixing unit 15, and the transfer paper is discharged onto the copy tray 16. The photoconductor belt 6
The toner remaining on the surface is cleaned by the cleaning unit 17 to enable the next image formation.

In the above structure, the transfer / separation unit section 20 integrally includes the transfer charger section 10, the separation charger section 11, the conveyor belt section 13, and the air suction section 14 on the unit frame body 19, and is generally shown in FIG. It is positioned at the right position. When a jam occurs on the transfer paper between the transfer / separation unit section 20 and the photoconductor belt 6, the transfer / separation unit 20 has an upper shaft portion 18 (FIG. 2) provided at a position to support one end of the transport belt 13. Is provided so as to be rotatable in a counterclockwise direction by a predetermined angle, the transfer charger unit 10 of the transfer separation unit 20 is separated from the photoconductor belt 6, and abuts against a stopper member (not shown) to stand still. be able to.

FIG. 3 shows a state in which the transfer paper 25 is jammed between the transfer separation unit 20 and the photosensitive belt 6. Further, a thin plate-shaped guide member 23 having elasticity is fixed to the bracket 22 fixed to the upper part of the registration roller pair 21 so that the tip end thereof comes close to the photosensitive belt 6.

FIG. 4 shows the transfer separation unit 20 with the upper shaft portion 18 provided at a position supporting one end of the conveyor belt 13 as a fulcrum to remove the jammed transfer paper 25 in FIG. It is shown that it rotates clockwise by a predetermined angle and is separated from the photoconductor belt 6. At this time, when the size of the transfer paper 25 is A3, double letter, etc. and the transfer paper is fed laterally, the transfer paper runs along the surface of the photoconductor belt 6 and the developing unit 8
It rarely falls in the direction of. But transfer paper
When 25 is laterally fed in the size of A4, letter, etc., it often happens that the transfer separation unit 20 drops along the surface of the photosensitive belt 6 toward the developing section 8 at the moment of separation.

However, as shown in FIG. 4, since the thin plate-shaped guide member 23 having elasticity is fixed and arranged so that its tip is close to the photoconductor drum 6, the transfer paper 25 has a small size such as A4 or letter. Even in the case of the size, it will not be caught by the guide member 23 and fall in the direction of the developing unit 8. Therefore, even if the transfer paper drops in the direction of the developing unit 8, the user does not notice that the transfer paper has fallen, and there is no inconvenience of noticing that an abnormality has occurred in an image or the like only after the copying is restarted.

In FIG. 5, the thin plate-shaped guide member 23 includes a base portion 23a and a tip portion 23b. The base portion 23a is fixed to the bracket 22,
A polyester film having lower rigidity than the bracket 22 is used. The tip portion 23b is located at a position where the tip portion faces the photoconductor belt 6 and uses a blade of polyurethane or EPDM having lower rigidity than the base portion 23a. When the transfer paper 25 hits the base portion or the tip end portion of the guide member 23, the guide member bends and the tip end portion 23b comes into contact with the photoconductor belt 6. Even in this case, since the rigidity of the tip portion 23b is low, the surface of the photosensitive belt 6 is not damaged.

In FIG. 6, a plurality of thin plate-shaped guide members 23 are attached to the bracket 22. Guide member tip 23b
Is placed close to the photoconductor belt 6, so it is difficult to mount a single wide guide member close to the photoconductor 6 in terms of part processing accuracy. Also, the guide member is functionally sufficient if it is installed within the width of the transfer paper that easily falls,
Therefore, as shown in FIG. 6, it is advantageous to divide the guide member into a plurality of parts.

Effect of the Invention The present invention prevents the transfer paper from dropping along the surface of the photoconductor, so that the inconvenient situation caused by restarting the copying without noticing that the transfer paper of a small size has dropped You can avoid it.

[Brief description of drawings]

FIG. 1 is an overall explanatory view of an electronic copying machine to which the present invention is applied, FIG. 2 is an enlarged view of a main part thereof, FIG. 3 is a view showing a transfer separation device portion when a jam occurs, and FIG. FIG. 5 is a diagram showing a transfer separation unit separated from the photoconductor belt and a fall state of a jammed transfer paper. FIG. 5 is a detailed view of a thin plate-shaped guide member.
FIG. 6 is a perspective view showing a modified example of the guide plate arrangement. 6 ... Photosensitive belt 8 ... Development part 10 ... Transfer charger 11 ... Separation charger 20 ... Transfer separation unit 23 ... Guide member 23a ... Guide member base 23b ... Guide member tip 25 ... Transfer paper

Claims (2)

(57) [Scope of utility model registration request] 1. A developing device for electrostatically attracting toner to the surface of a photoconductor to visualize an electrostatic latent image, a transfer separation device for transferring the visualized toner image onto a transfer paper, and In an electrophotographic apparatus provided with a guide member for preventing the transfer paper from falling near the surface of the photoconductor between the developing device and the transfer / separation device, the guide member is made of a polyester film. And an end portion made of polyurethane rubber which is close to the surface of the photosensitive member. 2. The electrophotographic apparatus according to claim 1, wherein a plurality of the guide members are arranged in a divided manner.