JPH04125673A - Transfer sheet separating mechanism - Google Patents

Abstract

PURPOSE:To prevent the damage of a photosensitive body by fixing a separation guide which guides a transfer sheet separated from the photosensitive body by a peeling pawl to a paper discharging side, at the main body of a copying machine so as not to be concerned in the rotating operation of the peeling pawl. CONSTITUTION:This device is equipped with a peeling pawl 3 whose top end is abutted to a photosensitive body 11 at the time of rotating in one direction, and whose top end is detached from the photosensitive body 11 at the time of rotating in the other direction, and a separation guide 4 which guides a transfer sheet 12 separated from the photosensitive body 11 to the paper discharging side. Then, the separation guide 4 is fixed to the main body of the copying machine so as not to be concerned in the rotating operation of the peeling pawl 3. That is, the separation guide 4 is fixed to the main body of the copying machine in a state in which the separation guide 4 is not concerned in the rotating operation of the peeling pawl 3. Because of this, even when a pressing force is added to the separation guide 4 by the transfer sheet 12, this force is not transmitted to the peeling pawl 3. Therefore, the peeling pawl 3 can be prevented from being pressed by the photosensitive body 11 than needed. Thus, the friction of the photosensitive body 11 can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field This invention is a method for separating the transfer sheet electrostatically attracted onto the photoreceptor from the photoreceptor after transferring the toner image on the photoreceptor to the transfer sheet. This invention relates to a transfer sheet separation mechanism.

(b) Prior Art FIG. 4 is a diagram showing the structure of the three components of a conventional transfer sheet.

A toner image is formed on the surface of the photoreceptor 110 by a charger, a developing device, etc. (not shown).

A transfer sheet 12 is fed to this photoreceptor from a paper feeding section (not shown) by a conveyance roller 22 or the like. Around the photoconductor 11, there is a transfer charger 13 that generates a corona discharge with a polarity opposite to the charged potential of the toner and transfers the toner image on the photoconductor 11 onto a transfer sheet 12, and a transfer charger 13 that generates a bipolar corona discharge with an AC power source. Peeling charger 1 that removes static electricity from the transfer sheet
4. A peeling claw 15, etc., which is rotatably supported and whose tip abuts against the photoreceptor 11 when necessary, is disposed. Transfer sheet 1
The toner image on the photoconductor 2 is transferred by a transfer charger 13 to the photoconductor 11, and is normally separated from the photoconductor 11 by a peeling charger 13. However, depending on the environmental conditions, the conditions of the transfer sheet, the process speed of image formation, etc., separation by the peeling charger 13 may not be possible, and in that case, separation is performed by the peeling claw 15.

FIG. 3 is a perspective view of the vicinity of the peeling claw 15.

The peeling claw 15 is fixedly held on a shaft 16 and is rotatable as the shaft 16 rotates. A rotation mechanism including a solenoid 17 and actuators 18 and 19 is provided at one end of the shaft 16. When the solenoid 17 is turned on, the actuators 18 and 19 operate to rotate the shaft 16,
The peeling claw 15 fixed to this shaft 16 is rotated.

When the solenoid 17 is turned on, the peeling claw 15 rotates in the direction of arrow B, and the tip of the peeling claw 5 separates from the photoreceptor 11.

By the way, the transfer sheet 12 separated from the photoreceptor 11 is conveyed on a suction belt 20 and sent to a fixing section (not shown). At this time, a peeling guide 21 was attached to the peeling claw 15 so that the transfer sheet 12 separated from the photoreceptor 11 would be reliably sent in the direction of the suction belt 20. The peeling guide 21 is made of a resin plate such as PET (polyethylene terephthalate), is attached in a rib shape, and functions to send the transfer sheet separated from the photoreceptor 11 toward the suction heald.

(c) Problems to be Solved by the Invention However, the above-described conventional peeling guide mechanism sometimes suffers from the following problems.

The transfer sheet 12 separated from the photoreceptor 11 hits the peeling guide 21 and is sent in the direction of the suction belt 20 by the rebound, but at this time, a force in the transport direction is applied to the transfer sheet 12 by the transport roller 22 etc. It is being This force in the conveying direction is in the same direction as the direction in which the peeling claw 15 comes into contact with the photoreceptor 11 . Therefore, a force is applied to the peeling guide 21 and the peeling claw 15 to which the peeling guide 21 is fixed in the direction of contacting the photoreceptor. As a result, the peeling claw 15 is subjected to more contact force than necessary against the photoreceptor 11, and the frictional force between the photoreceptor 11 and the peeling claw 15 increases, which tends to cause streak-like scratches on the surface of the photoreceptor 11. Was.

In particular, if a jam occurs at the position of the peeling claw 15, the transfer sheet 12 may fold into the peeling guide 21 as shown in FIG. The force could become so great that it could instantly cause large scratches on the surface of the photoreceptor 11.

Such scratches appear as streaky image gaps in the formed image,
This will reduce the image quality.

In view of these problems, an object of the present invention is to provide a transfer sheet peeler that prevents the photoreceptor from being damaged by preventing the peeling claw from being pushed up even when the peeling guide is pushed up by the transfer sheet. The purpose is to provide a guide mechanism.

(Means for Solving Problem d1) The present invention is a transfer sheet separation mechanism for separating a transfer sheet adsorbed onto the surface of a photoreceptor from the surface of the photoreceptor, which is rotatably supported and rotates in one direction. A peeling claw whose tip comes into contact with the photoreceptor when rotated, and detaches from the photoreceptor when rotated in the other direction, and guides the transfer sheet separated from the photoreceptor to the paper ejection side by the peeling claw. and a separation guide, wherein the separation guide is fixedly arranged on the copying machine main body so as not to be involved in the rotational movement of the peeling claw.

(e) Function In the present invention, the peeling guide is fixedly arranged on the copying machine main body without being involved in the rotational movement of the peeling claw at all. Therefore, even if a pressing force is applied to the peeling guide by the transfer sheet, this force will not be transmitted to the peeling claw. Therefore, the peeling claw is not pressed against the photoreceptor more than necessary.

(f) Embodiment FIG. 2 is a diagram showing the structure of a transfer sheet in the vicinity of a peeling guide mechanism according to an embodiment of the present invention, and FIG. 1 is a perspective view of the same guide mechanism. Note that in the figures, parts similar to those in the conventional configuration are indicated by the same numbers, and explanations thereof will be omitted.

A frame steel plate 2 is attached to a frame l of the main body of the copying machine. The frame steel plate 2 is provided above the peeling claw 3 along the axial direction of the photoreceptor 11. The frame steel plate 2 supports the peeling guide 4 on the side of the peeling claw 3. The peeling guide 4 is made of PET or the like and is formed into a thin plate shape, and is fixed to the lower surface of the frame steel plate 2 so as to protrude in a rib shape. Looking at the peeling guide 4 from the front side,
As shown in FIG. 2, the transfer sheet is shaped to draw a gentle curve so that it is fed downward along the conveyance direction (direction of arrow C) of the transfer sheet. therefore,
The transfer sheet 12 is slowly fed to the suction belt 20 along this peeling guide 4. On the other hand, peeling claw 3
No peeling guide is attached to the , and the peeling claw 3 can only be moved up and down by the operation of the solenoid 17 (as shown by arrows A and B).
direction).

The operation of the transfer sheet peeling guide mechanism configured as described above will be explained. When the transfer sheet 12 on the photoreceptor 11 is peeled off, the peeling claw 3 is rotated in the direction of arrow A and comes into contact with the photoreceptor 11 . Then, the leading edge of the transfer sheet 12 is scraped off from the surface of the photoreceptor 11 by the peeling claw 3. The transfer sheet 12 then hits the peeling guide 4 and is sent toward the suction belt 20 by the rebound force. At this time, a pressing force is applied to the peeling guide 4 by the conveying force of the conveying roller 22 and the like. However, this pressing force is not transmitted to the peeling claw 3, and no extra pressing force is applied to the peeling claw 3. Therefore, no extra frictional force is generated between the photoreceptor 11 (and wear of the photoreceptor 11 is not accelerated).

This is also the case when the transfer sheet 12 jams at the position of the peeling claw 3. Even if the jammed transfer sheet 12 applies a large pressing force to the peeling guide 4, this may cause the peeling claw 3 to The photoreceptor 11 will not be adversely affected.

(As described above, in this invention, the conveyance force of the transfer sheet exerts a pressing force on the peeling guide, but this pressing force is not transmitted to the peeling claw, and the peeling claw does not have more force than necessary.) Power,
In other words, a force that presses the photoreceptor more than necessary is not applied. This reduces wear on the photoconductor and prevents the life of the photoconductor from being shortened.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a transfer sheet peeling guide mechanism according to an embodiment of the present invention, and FIG. 2 is a diagram showing the main part configuration of an image forming apparatus equipped with the same mechanism. Furthermore, Fig. 3 is a perspective view of the main parts of a conventional peeling guide mechanism, Fig. 4 is a configuration diagram of the conventional peeling guide mechanism, and Fig. 5 shows a state in which a jam occurs in the peeling claw part in the conventional mechanism. It is a diagram. 2-Frame steel plate, 3-Peeling claw, 4-Peeling guide,
11-Photoreceptor, 12-Transfer sheet, 13-Transfer charger, 4-Peeling charger. Dekujin Sharp Co., Ltd.

Claims (1)

[Claims] (1) A transfer sheet separation mechanism that separates the transfer sheet adsorbed to the photoreceptor surface from the photoreceptor surface, which is rotatably supported and when rotated in one direction, the leading end touches the photoreceptor. A peeling pawl whose tip portion comes into contact with the photoconductor and separates from the photoconductor when rotated in the other direction, and a separation guide that guides the transfer sheet separated from the photoconductor by the peeling pawl to the paper ejection side, A transfer sheet separation mechanism characterized in that a guide is fixedly arranged on a copying machine body so as not to be involved in the rotational movement of a separation claw.