JP2000066526A - Transfer device and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a transfer device by which even a recording medium having unevenness and a difference in level is brought into close contact with an image carrier and a transferred image whose quality is excellent can be obtained by constituting a part of the abutting part of a transfer guide on a recording medium of a flexible material. SOLUTION: A part of the abutting part of a transfer guide on a recording medium is constituted of a flexible material. Recording paper 20 is transferred in the direction of an arrow A along the transfer guide 12 at a transfer process of a developed image at this device. In this case, since an upper guide 10 is constituted of the flexible material, it is deformed in accordance with the difference in the level of the recording paper 20 and both the thick port part 14 and the thin port part 15 of the recording paper 20 are brought into close contact with a photoreceptive drum. At this time, the upper guide 10 is deformed without being affected a little by the areas where each part is adjacent in the width direction of the recording paper 20. Therefor, each part of the recording medium is uniformly brought into close contact with a photoreceptive drum through it is the recording medium having a difference in level in the width direction such as the recording medium 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transfer device that can be suitably used in an image forming apparatus such as an electrophotographic apparatus and a printing machine.

[0002]

2. Description of the Related Art Generally, in an electrophotographic apparatus, a latent image formed on a photosensitive drum is developed with toner, and then the image is transferred onto a recording paper and fixed. In the transfer step, a transfer roller and a transfer guide are used to bring the recording paper and the photosensitive drum into close contact.

In order to improve the quality of a transferred image, it is necessary to improve the adhesiveness between the recording paper and the photosensitive drum and to uniformly adhere the respective portions of the recording paper. However, if the recording paper has irregularities or steps, the adhesion may be uneven, resulting in poor transfer or uneven transfer. This is because the transfer roller and the transfer guide are usually made of a harder material than the recording paper, for example, stainless steel, so that they do not deform smoothly following the shape of the paper, and the adhesion at the convex portion of the recording paper is poor. This is because the adhesiveness becomes high and the adhesion becomes insufficient in the concave portion.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and to make the recording medium having irregularities or steps adhere to the image carrier. An object of the present invention is to provide a transfer device capable of obtaining a transfer image of excellent quality.

Another object of the present invention is to provide an image forming apparatus and an image forming method using the above-described transfer device.

[0006]

In order to achieve the above object, the present invention provides a transfer device for transferring an image on an image carrier onto a recording medium, the transfer device being in contact with the recording medium and being transferred to the recording medium. A transfer guide in which at least a part of a contact portion of the transfer guide that contacts the image carrier with the recording medium is made of a flexible material.

A transfer device for transferring an image on an image carrier onto a recording medium, wherein a transfer guide for contacting the recording medium and bringing the recording medium into contact with the image carrier is provided between the transfer guide and the recording medium. Provided is a transfer device in which at least a part of an abutting portion is divided into a plurality in the width direction of a recording medium, and each of the divided portions can be elastically deformed and / or displaced.

Here, it is preferable that the transfer guide is composed of a plurality of members.

Further, the present invention provides an image forming apparatus and an image forming method using the above-described transfer device.

[0010]

FIG. 1 is a schematic front view of an electrophotographic apparatus provided with a transfer device of the present invention.

The electrophotographic apparatus 1 includes a light source 3, a developing device 4, a transfer guide 12, a transfer charger 5, a separation charger 6, a cleaner 7, a static elimination lamp 8, around a photosensitive drum 2 (image carrier).
The recharger 9 is arranged in this order, and the fixing device 30 is arranged.

The transfer guide 12 is a lower guide 11 for guiding the recording paper 20 (recording medium) onto the photosensitive drum 2.
And an upper guide 10 for bringing the recording paper 20 into close contact with the photosensitive drum 2.

FIG. 2 is a schematic perspective view showing the transfer guide portion.

The transfer guide 12 includes a lower guide 11 and an upper guide 10 made of a flexible material. The recording paper 20 has a thick mouth portion 14 having a laminated structure and a thin mouth portion 15 having a smaller thickness, and is arranged along the arrow A which is the transport direction. The direction of arrow B is the width direction of the recording medium.

FIG. 3 is a schematic perspective view of the recording paper 20 described above.

In the figure, the direction of arrow A indicates the direction of conveyance of the recording medium, and the direction of arrow B perpendicular thereto indicates the width direction of the recording medium.

In FIG. 1, the latent image formed on the photosensitive drum 2 by the light source 3 is developed in the developing device 4, and a developed image is formed on the photosensitive drum 2. Recording paper 2
0 is extruded by a conveying roller or the like, closely adheres to the photosensitive drum 2 at a transfer position 13 along a transfer guide 12, and a developed image is transferred to a recording paper 20 by a transfer charger 5.
The recording paper 20 to which the developed image has been transferred is separated from the photosensitive drum 2 by the separation charger 6, and after the developed image is fixed by the fixing device 30, the recording paper 20 is discharged out of the electrophotographic apparatus. After transferring the developed image, the photosensitive drum 2 physically removes paper dust and remaining toner from the recording paper 20 by the cleaner 7, passes through the neutralization by the neutralization lamp 8 and the electrification by the recharger 9, and returns to the latent image again. Provided for image formation.

In the transfer step of the developed image, the recording paper 2
0 is conveyed along the transfer guide 12 in the direction of arrow A in the figure as shown in FIG. At that time, the upper guide 10
Since the recording paper 20 is made of a flexible material, the recording paper 20 is deformed in accordance with the step, and the thick paper 14 and the thin paper 15
Are brought into close contact with the photosensitive drum 2. At this time, the upper guide 10 is deformed in the width direction of the recording paper 20 with almost no effect of adjacent areas. For this reason, even in the case of a recording medium having a step in the width direction like the recording paper 20, each part of the recording medium uniformly adheres to the photosensitive drum 2.

As the flexible material, an elastic material,
For example, urethane rubber, neoprene rubber or sponge can be used. In order to improve transfer quality, these materials may be provided with conductivity.

FIG. 4 shows another embodiment in which the contact portion of the transfer guide with the recording medium is divided into a plurality.

The transfer guide 17 includes an upper guide 16 and a lower guide 11. As the upper guide 16, the one shown in FIG. 5 was used. The slit 18 is provided in a flat plate of stainless steel (SUS304) having a thickness of 0.1 mm. The slit 18 is formed substantially parallel to the recording medium transport direction A, and is arranged along the width direction B of the recording medium. The length of the slit is 10 mm, the width is 0.5 mm, and the interval is 3 mm.

In FIG. 4, the recording paper 20 is conveyed in the direction of arrow A. At this time, the divided portions of the upper guide 16 are elastically displaced according to the thickness of the recording paper 20. For this reason, both the thick portion 14 and the thin portion 15 of the recording paper 20
The upper guide 16 makes close contact with the photosensitive drum 2.

When the slits are provided as described above, the width of each slit is 1 mm or less, more preferably 0.6 mm or less. The length of the slit is 2-3
0 mm, more preferably 5 to 1 mm.
5 mm. By forming in this manner, each part of the recording medium can be uniformly brought into close contact with the photosensitive drum 2. When the slits are arranged at equal intervals, the intervals are preferably 2 to 20 mm, more preferably 3 to 6 mm. The intervals at which the slits are arranged may be arbitrarily changed between the slits.

When the transfer guide is composed of a plurality of members, a plurality of plate members are arranged in the width direction to form the slit structure as described above, or a plurality of flexible materials are formed in the width direction. , And each can be independently deformed.

It is not necessary to provide the transfer guide divided in the width direction or a portion made of a flexible material over the entire width direction. For example, the transfer guide may be provided only at both ends or only at the center. Good.

The transfer device as described above is usually used for an image forming apparatus such as an electrophotographic apparatus and a printing machine.

[0027]

According to the present invention, at least a part of the contact portion of the transfer guide with the recording medium is made of a flexible material, or each part of the recording medium is elastically deformed or displaced. Because it is divided into multiple parts in the width direction,
It is possible to obtain a transfer device capable of obtaining a transfer image with excellent image quality even on a recording medium having irregularities or steps.

Further, by providing the above-described transfer device, it is possible to obtain an image forming device capable of obtaining a high-quality transfer image.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing an electrophotographic apparatus provided with a transfer device of the present invention.

FIG. 2 is a schematic perspective view showing one embodiment of a transfer guide in the transfer device of the present invention.

FIG. 3 is a schematic perspective view showing a form example of a recording medium.

FIG. 4 is a schematic perspective view showing another embodiment of the transfer guide in the transfer device of the present invention.

FIG. 5 is a schematic plan view showing an upper guide of a transfer guide shown in FIG. 4;

[Explanation of symbols]

 1. Electrophotographic device 2. 2. Photosensitive drum (image carrier) Light source 4. Developing device 5. Transfer charger 6. Separation charger 7. Cleaner 8. 8. Static elimination lamp Recharger 10. Upper guide 11. Lower guide 12. Transfer guide 13. Transfer position 14. Thick mouth 15. Thin mouth 16. Upper guide 17. Transfer guide 18. Slit 20. Recording paper (recording medium) 30. Fuser

Claims (5)

[Claims] 1. A transfer device for transferring an image on an image carrier onto a recording medium, wherein a transfer guide for contacting the recording medium and bringing the recording medium into contact with the image carrier is provided. A transfer device, wherein at least a part of the contact portion is made of a flexible material. 2. A transfer device for transferring an image on an image carrier onto a recording medium, wherein a transfer guide for contacting the recording medium and bringing the recording medium into contact with the image carrier is provided. A transfer device, wherein at least a part of the contact portion is divided into a plurality of pieces in the width direction of the recording medium, and each of the divided portions can be elastically deformed and / or displaced. 3. The transfer device according to claim 1, wherein said transfer guide is constituted by a plurality of members. 4. An image forming apparatus comprising the transfer device according to claim 1. 5. An image forming method using the transfer device according to claim 1 to transfer an image formed on an image carrier to a recording medium.