JPH06222682A - Transfer and separation device - Google Patents

Abstract

PURPOSE:To obtain a transfer and separation, device where there is no trouble such as occurrence of an abnormal image, faulty transfer, faulty separation and leakage by providing a 1st insulating guide member at the aperture part of a separation destaticizer and a 2nd guide member on the downstream side of the separation destaticizer. CONSTITUTION:The separation destaticizer 9 is provided with a corona wire 17 consisting of a metallic material such as tungsten inside, the 1st insulating guide member 10 preventing transfer paper 16 from entering the inside of the destaticizer 9 at the aperture part, and the 2nd guide member 11 consisting of a rotating body supporting the transfer paper 16 while rotating in contact with the back surface of the transfer paper following it and having a saw-toothed peripheral surface on the downstream side of the member 10; and it is arranged so that the transfer paper 16 is separated from a photosensitive body 1. The transfer paper 16 is fed to the member 11 along the member 10 and progresses to a fixing stage in a state where it is supported while it rotates the member 11 by its back surface. Therefore, the abnormal image caused by triboelectrification is prevented from occurring, and transfer and separation is performed without spoiling the contact of the transfer paper 16 with the photosensitive body 1.

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 using corona discharge separation.

[0002]

2. Description of the Related Art The transfer paper is neutralized by corona discharge,
The separation static eliminator that separates the transfer paper from the surface of the image carrier,
A method of providing a guide member in order to prevent the transfer paper from entering the inside of the separation charge eliminator is known.

[0003]

A conventional guide member for preventing transfer paper intrusion is composed of an insulating member, and when the transfer paper is conveyed while being in strong contact with the guide member, friction between the transfer paper and the guide member is caused. Due to the charging, there is a problem that the toner transferred onto the transfer paper is scattered and an abnormal image is generated. As a means for solving this problem, it is introduced that the height of the guide member is made lower than that of the conventional one so that the frictional force acting between the transfer paper and the guide member is weakened, but the transfer paper vibrates. As a result, poor adhesion between the image carrier and the transfer paper occurs at the transfer section, resulting in poor image transfer. Therefore,
Japanese Unexamined Patent Publication No. 1-304480 discloses a method in which a conductive member is provided on the side of the guide member that contacts the transfer paper.

In the method of providing the guide member with the conductive member, the conductive member is provided in the corona discharge region.
There is a risk of leakage due to high-voltage discharge, and corona discharge is not sufficiently performed due to the leakage and there is a problem such as improper separation of transfer paper or ignition. The present invention solves these problems,
It is an object of the present invention to provide a transfer / separation device without the risk of transfer failure, separation failure, or leak.

[0005]

A transfer / separation apparatus of the present invention is an image forming apparatus of the type in which an electrostatic latent image formed on the surface of an image carrier is developed and the resulting toner image is electrostatically transferred onto a transfer paper. 2. A transfer separation device including a separation charge eliminator for removing charge from a transfer paper on which a toner image has been transferred to separate the transfer paper from the surface of the image carrier, and has an insulating first guide member and a second guide member.

The first guide member is provided at the opening of the separation charge eliminator to prevent the transfer paper from entering the separation charge eliminator. The second guide member is in contact with the back surface of the transfer paper and supports and guides the transfer paper on the downstream side of the separation charge eliminator in the transfer paper conveyance direction while being driven to rotate. According to a second aspect of the present invention, there is provided the transfer / separation device according to the first aspect, wherein the peripheral surface of the second guide member has a sawtooth shape.

According to a third aspect of the present invention, there is provided a transfer / separation device in which an electrostatic latent image formed on the surface of an image bearing member is developed and a toner image obtained is electrostatically transferred onto a transfer paper.
A transfer separation device comprising a separation charge eliminator for removing charge from a transfer paper on which a toner image has been transferred to separate it from the surface of an image carrier.
It has a guide member. The guide member is provided in the opening of the separation static eliminator to prevent the transfer paper from entering the separation static eliminator, and to have a conductive material or conductive treatment outside the discharge area of the separation static eliminator and on the contact side of the transfer paper. It is characterized by having a part given.

[0008]

The transfer paper on which the toner image on the surface of the image carrier is electrostatically transferred by the transfer charger is separated from the surface of the image carrier by the separation charge eliminator and is guided to the second guide member along the first guide member. . Thereafter, the transfer sheet is supported and conveyed to the fixing device without causing the second guide member to rotate on its rear surface, that is, without causing triboelectric charging. According to the third aspect of the present invention, the transfer paper separated from the surface of the image carrier is guided by the conductive portion provided on the guide member, and is conveyed without causing triboelectric charging.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 2, the photoconductive photosensitive drum 1 as an image carrier is indicated by an arrow A by a rotation driving means (not shown).
Rotates at a constant speed in the direction of. The photoconductor drum 1 is formed by forming a photoconductive layer on the surface of a conductive support. The surface of the photoconductor drum 1 is uniformly charged by a charging device 2 and exposed at an exposure position to form an electrostatic latent image. It

The toner supplied by the developing device 3 electrostatically adheres to the electrostatic latent image moved to the developing position by the rotation of the photosensitive drum 1, and a toner image is formed on the surface of the photosensitive drum. A registration roller pair 4, a paper feed roller pair 5, a paper distribution roller 6, and a paper feed cassette 7 are arranged at a predetermined distance from the photoconductor 1. The transfer sheets stacked in the paper feed cassette 7 are distributed by the paper distribution roller 6 toward the paper feed roller pair 5. The registration roller pair 4 sends the transfer paper conveyed by the paper feed roller pair 5 to the transfer position where the transfer charger 8 is arranged in synchronization with the movement of the toner image on the photoconductor 1.

The toner image moves to the transfer position by the rotation of the photosensitive member 1 and is transferred to the transfer paper by the transfer charger 8. On the downstream side of the transfer charger 8, a separation charge eliminator 9 that removes charge from the transfer paper and separates it from the photoconductor 1 is arranged. In the opening of the separation static eliminator 9, a plurality of insulating first guide members 10 elongated in the moving direction of the transfer paper for preventing the transfer paper from entering the separation static eliminator 9 are formed in a direction crossing the separation static eliminator 9. It is provided. Further, on the downstream side of the first guide member 10, a second guide member 11 composed of a rotating body that is in contact with the back surface of the transfer paper and is driven to rotate and supports the transfer paper is disposed. The transfer paper on which the toner image has been transferred is de-charged and separated from the photoconductor 1 by the de-electrifier 9, and the first guide member 1
It is guided to the second guide member 11 along 0. afterwards,
The transfer sheet is supported while rotating the second guide member 11 on the back surface thereof, and is transported to the fixing device 13 by the transport belt 12.

The fixing device 13 has a heating roller 14 having a heating means (not shown) such as a heater therein, and a pressure roller 15 in pressure contact with the heating roller 14. The heating roller 14 heats the toner image on the transfer paper. Fixing is performed by fusing the transfer paper. The transfer paper on which the image is fixed is conveyed to a tray (not shown). On the other hand, the photoconductor 1 is cleaned by the cleaning device 19 of residual toner and the like remaining on the photoconductor 1 for the next image formation.

The separation static eliminator 9 will be described in more detail below with reference to FIGS. 1 and 3. Hereinafter, the same members as those in FIG. 2 are designated by the same reference numerals. The separation static eliminator 9 has therein a corona wire 17 made of a metal material such as tungsten, an insulating first guide member 10 for preventing the transfer paper 16 from entering the inside of the separation static eliminator 9 in its opening, 1 guide member 10
And a second guide member 11 having a sawtooth-shaped peripheral surface for supporting the transfer paper 16 while being driven to rotate in contact with the back surface of the transfer paper on the downstream side of the transfer paper 16. It is arranged to separate from 1.

The first guide member 10 is, as shown in FIG.
Separating wall 9 for separating the static eliminator 9 and the transfer charger 8
It is arranged so as to bridge the upper end of the a and the upper surface 9b of the downstream end of the separation static eliminator 9. The second guide member 11 has a saw-toothed peripheral surface, and is rotatably supported by a shaft 11j provided on the shoulder 10a of the first guide member 10.
In addition, in this embodiment, two first guide members 10 and two second guide members 11 are arranged in the separation charge eliminator 9, but the number is not limited to two.

The movement of the transfer paper 16 in this embodiment will be described. The transfer paper 16 is conveyed to the gap between the transfer charger 8 and the photoconductor 1 by the conveying means,
Thus, the toner image on the photoconductor 1 is transferred by receiving corona discharge having a polarity opposite to that of the toner. At this time, the transfer paper 16 is attracted to the surface of the photoconductor 1 by electrostatic force. Next, the transfer paper 16 is neutralized by the corona discharge of the separation static eliminator 9, and the electrostatic force acting between the photoconductor 1 and the transfer paper 16 is weakened and separated from the photoconductor 1. After that, the transfer paper 16 is conveyed to the second guide member 11 along the first guide member 10, is supported while rotating the second guide member 11 on its back surface, and proceeds to the fixing step. Therefore, an abnormal image due to frictional charging between the first guide member 10 and the transfer paper 16 does not occur,
Further, transfer separation can be performed without impairing the close contact between the transfer paper 16 and the photoconductor 1 during transfer.

Next, an embodiment of the transfer separation device according to the third aspect will be described with reference to FIG. The separation static eliminator 9 has a corona wire 17 made of a metal material such as tungsten inside, and a guide member 101 for preventing the transfer paper 16 from entering the inside of the separation static eliminator 9 in its opening. It is arranged to separate 16 from the photoconductor 1. As shown in FIG. 4, the separation member 101 is arranged so as to bridge the upper end of the partition wall 9a that divides the separation charge eliminator 9 and the transfer charger 8 and the upper surface 9b of the downstream end of the separation charge eliminator 9. The separating member 101 is composed of an insulating member, a part of which is
That is, the conductive portion 1 is located outside the discharge area of the separation static eliminator 9 at the downstream end with respect to the transfer paper transport direction and on the side in contact with the transfer paper 16.
It is composed of 8. The transfer paper 16 on which the toner image on the surface of the photoconductor 1 has been transferred is neutralized by the corona discharge of the separation charge eliminator 9, and the electrostatic force acting between the photoconductor 1 and the transfer paper 16 is weakened and separated from the photoconductor 1. It After that, the transfer paper 16 is conveyed to the fixing process along the guide member 101. Therefore, in the portion where the transfer paper 16 is in strong contact with the guide member 101, no abnormal image is generated without being triboelectrically charged.

[0017]

As described above, according to the present invention,
Since the insulating first guide member is provided at the opening of the separation charge eliminator and the second guide member is provided at the downstream side of the separation charge eliminator, there is a risk of abnormal image generation, transfer failure, separation failure, and leakage. It is possible to provide a transfer separation device that does not have a transfer unit.

[Brief description of drawings]

FIG. 1 is a side view of a transfer separation device showing an embodiment of the present invention.

FIG. 2 is a front view of a copying machine to which the transfer separation device of the present invention is applied.

FIG. 3 is a perspective view showing a transfer separation device.

FIG. 4 is a diagram showing a characteristic part of one embodiment of the transfer separation device according to the third aspect of the invention.

[Explanation of symbols]

 1 Photoreceptor 3 Developing Device 8 Transfer Charger 9 Separating Charger 10 First Guide Member 11 Second Guide Member 13 Fixing Device 16 Transfer Paper 17 Corona Wire 18 Conductive Part 101 Guide Member

Claims (3)

[Claims] 1. An image forming apparatus of a system in which an electrostatic latent image is formed on a surface of an image carrier that is cyclically moved, the electrostatic latent image is developed, and the obtained toner image is electrostatically transferred onto a transfer paper. A transfer separation device equipped with a separation charge eliminator for removing charge from a transfer paper on which a toner image has been transferred to separate it from the surface of an image carrier, wherein the transfer paper is provided in an opening of the separation charge eliminator, Insulating first guide member for preventing invasion into the electric device, and second guide for supporting and guiding while contacting the back surface of the transfer paper while being driven to rotate downstream of the separation static eliminator in the transfer paper conveyance direction. And a transfer separating device. 2. The transfer separating apparatus according to claim 1, wherein the peripheral surface of the second guide member is serrated. 3. An image forming apparatus of the type in which an electrostatic latent image is formed on the surface of an image carrier that moves cyclically, the electrostatic latent image is developed, and the resulting toner image is electrostatically transferred onto a transfer paper. A transfer separation device equipped with a separation charge eliminator for removing charge from a transfer paper on which a toner image has been transferred to separate it from the surface of an image carrier, wherein the transfer paper is provided in an opening of the separation charge eliminator, and the transfer paper is separated and removed. A transfer member having a guide member provided with a conductive material or a portion subjected to a conductive treatment outside the discharge area of the separation static eliminator and on the contact side of the transfer paper. Separation device.