JPH10254268A - Image forming device - Google Patents

Abstract

An object of the present invention is to provide an image forming apparatus capable of uniformly fixing an entire toner image forming one print image by a simple fixing device heat source temperature control. SOLUTION: A toner image carried on a toner image carrier 1 stretched by a plurality of rollers in a direction perpendicular to the transport direction of the print paper is transferred by a transfer opposing roller 8 in a direction Y perpendicular to the transport direction X of the print paper 7. An image forming apparatus of an orthogonal transfer system in which the toner image transferred to the printing paper is fixed by a fixing device 13 and the fixing device is connected to a transfer opposing roller by a connecting member 14.

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 an orthogonal transfer system for transferring a toner image onto a print sheet in a direction perpendicular to a conveying direction of the print sheet.

[0002]

2. Description of the Related Art In recent years, toner-type image forming apparatuses capable of forming clear images with high resolution, such as laser printers, have become widespread. Among such toner-type image forming apparatuses, as proposed in Japanese Patent Application No. 7-328600, the toner image carrier is moved while moving the toner image carrier in a direction orthogonal to the printing paper conveyance direction. An orthogonal transfer type image forming apparatus that rubs on a printing paper and transfers a toner image in small steps one by one is very suitable for promoting miniaturization of a product due to its configuration.

Hereinafter, a conventional image forming apparatus using such an orthogonal transfer system will be described. FIG. 2 is a structural view showing a conventional image forming apparatus of the orthogonal transfer system, and FIG. 3 is a perspective view of a main part showing a main part of the conventional image forming apparatus of the orthogonal transfer system. 2 and 3, reference numeral 1 denotes a toner image carrier formed of a photosensitive belt, 2 denotes a charger, 3 denotes a developing device, 3a denotes a toner, 3b denotes a developing roller, 3c denotes a toner image, 4 denotes a cleaning device, and 5 denotes a cleaning device. Static eliminator, 6 is an exposure unit, 7 is printing paper, 8
Is a transfer opposing roller, 9 is a displacement roller, 10 is a transfer plate, 1
1 is a fixing device, and 12 is a paper discharge roller.

The arrangement, operation, and the like of the image forming apparatus configured as described above will be described. As shown in FIG. 2, the toner image carrier 1 whose surface is coated with a layer of an organic photoconductive material is stretched by a plurality of rollers in a direction perpendicular to the transport direction X of the printing paper 7 (see FIG. 3). Yes,
At the time of image formation, a toner image is formed on the surface of the toner image carrier 1 by rotating in the direction of arrow A. Around the toner image carrier 1, a cleaning device 4, a static eliminator 5, a charging device 2, and a developing device 3 are sequentially arranged in the rotation direction of the toner image carrier 1 (the direction of arrow A). An exposing device 6 for irradiating a laser beam 6a is disposed on the upper part of the device 1.

When the toner image carrier 1 rotates in the direction (transfer direction) Y orthogonal to the transport direction X of the printing paper 7 as shown by the arrow A, the portion passing through the charger 2 is charged, and based on the image signal. An electrostatic latent image is formed on a portion irradiated with the laser beam 6a by the exposure device 6.

The toner 3 is applied to the portion where the electrostatic latent image is formed.
a is pressed by the developing roller 3b, the toner image carrier 1
The toner images 3c that have become visible images appear one after another. Next, when the transfer opposing roller 8 is moved in the direction Y orthogonal to the transport direction X of the printing paper 7, the toner image 3 c is
Is transferred to

In a conventional parallel transfer type image forming apparatus using a photosensitive drum or the like, the conveying direction of the photosensitive drum and the printing paper is the same, and it is necessary to form one image. What is necessary is just to develop and transfer one page. However, in the image forming apparatus of the orthogonal transfer system, development and transfer are not for one page, but for the width in which toner can be placed on the photosensitive belt, that is, for the width of the developing device 3. Therefore, in order to form an image for one page, a plurality of development and transfer operations are required, and when one development and transfer operation is completed, the printing paper 7 is conveyed by the width of the developing device 3. Need to stop. Therefore, a method of fixing a toner image by providing a heat roller or the like used in a parallel transfer type image forming apparatus in a direction Y orthogonal to the transport direction X of the printing paper 7 (a heat roller contact fixing method) is orthogonal. When used in a transfer type image forming apparatus, the printing paper 7 repeatedly conveys and stops for each width of the developing device 3, so that the printing paper 7 comes into contact with the heat roller for a long time,
Excessive fixing due to prolonged contact causes problems such as deterioration of image quality and warpage of the printing paper 7.

As a countermeasure, in a conventional image forming apparatus of the orthogonal transfer type, a non-contact fixing device 11 having a heating element therein is provided at a position as shown in FIG. 3 to fix a toner image. In this fixing method, since the fixing device 11 does not come into contact with the printing paper, problems such as image quality deterioration due to excessive fixing are less likely to occur as compared with a heat roller contact fixing method used in a parallel transfer type image forming apparatus.

[0009]

However, in the above-mentioned conventional image forming apparatus, the problem of image quality deterioration due to excessive fixing is unlikely to occur, but since the heat source is always above the toner image on the printing paper 7, the heat source There was a problem that temperature control was difficult. That is, if the temperature of the heat source is too high, excessive fixing may occur, and if the temperature of the heat source is too low, insufficient fixing may occur. Therefore, the entire toner image forming one print image is uniformly formed. There is a problem that it is necessary to control the rise and fall of the temperature of the heat source very finely according to when the printing paper 7 is being conveyed and when it is stopped.

In this image forming apparatus, it is required that the entire toner image forming one print image be uniformly fixed by a simple fixing device heat source temperature control.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus capable of uniformly fixing an entire toner image forming one print image by simple control of a fixing device heat source temperature.

[0012]

SUMMARY OF THE INVENTION In order to solve this problem, an image forming apparatus according to the present invention is directed to a toner carried on a toner image carrier stretched by a plurality of rollers in a direction perpendicular to a conveying direction of a printing paper. An orthogonal transfer type image forming apparatus in which an image is transferred to printing paper in a direction orthogonal to the conveying direction of the printing paper by a transfer facing roller, and the toner image transferred to the printing paper is fixed by a fixing device. A structure is provided in which the transfer member is connected to the transfer opposing roller by a connecting member.

Thus, an image forming apparatus capable of uniformly fixing the entire toner image forming one print image by simple temperature control of the fixing device heat source can be obtained.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to a first aspect of the present invention is directed to a roller for transferring a toner image carried on a toner image carrier stretched by a plurality of rollers in a direction perpendicular to the conveying direction of the printing paper. Is an image forming apparatus of an orthogonal transfer system in which a toner image transferred to the printing paper is fixed by a fixing device by transferring the toner image onto the printing paper in a direction orthogonal to a conveying direction of the printing paper by a fixing member. When the print paper is conveyed and stopped, the fixing unit waits at a place other than above the print paper to transfer the toner image carried on the toner image carrier onto the print paper. Only the transfer roller moves on the printing paper together with the transfer opposing roller.

According to a second aspect of the present invention, in the first aspect of the present invention, the fixing unit has a fixing width equal to the developing unit width. This has the effect that the fixing device does not move again above the fixed toner image.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 is a perspective view showing a main part of an image forming apparatus according to Embodiment 1 of the present invention. In FIG. 1, a toner image carrier 1, a developing unit 3, an exposing unit 6, a printing paper 7, a transfer opposing roller 8, a displacement roller 9, and a discharge roller 1
2 is the same as that of FIG. 3, and therefore, is denoted by the same reference numerals and description thereof is omitted. Reference numeral 13 denotes a fixing device having a fixing width W equal to the width of the developing device 3, and reference numeral 14 denotes a connecting member for connecting the fixing device 13 to the transfer opposing roller 8.

The developing operation of the image forming apparatus configured as described above is the same as the developing operation of the conventional image forming apparatus, and the toner image carrier 1 formed of a photoreceptor belt is orthogonal to the conveying direction X of the printing paper 7. In the direction of transfer (transfer direction) Y, and a portion charged by the charger 2 (see FIG. 2) is irradiated with laser light 6a (see FIG. 2) by the exposure device 6 to form an electrostatic latent image. The developing device 3 rubs the toner on the portion where the electrostatic latent image is formed to form a toner image. When the developing operation is completed, the transfer opposing roller 8 is moved in a direction Y orthogonal to the conveying direction X of the printing paper 7 in order to transfer the toner image formed on the toner image carrier 1 to the printing paper 7, and the printing is performed. The transfer to the paper 7 is performed. The movement of the transfer opposing roller 8 is a linear movement without rotation.

When the transfer opposing roller 8 moves, the fixing device 13 integrally connected to the transfer opposing roller 8
Moves in the direction Y orthogonal to the transport direction X of the printing paper 7 in accordance with the moving operation of. The fixing device 13 needs to generate heat in order to fix the toner image transferred on the printing paper 7. However, when the printing paper 7 is transported and stopped, the transfer opposing roller 8 is at a standby position and is integrally connected. Fixing unit 1
Since the printing paper 3 does not exist above the printing paper 7, the printing paper 7 is not excessively fixed.
A non-contact type in which fixing is performed in a non-contact manner with the printing paper 7 may be used. As a contact type, there is a type using a heat roller or the like, and as a non-contact type, a type using a halogen lamp or the like is used. Since it does not stop on the print paper 7 and moves on the printing paper 7 at a constant speed, an excessively fixed portion or an insufficiently fixed portion does not occur. Further, the temperature of the fixing device 13 may be kept constant, and the temperature control of the fixing device 13 is facilitated.

The fixing width W of the fixing device 13 is
In this manner, the width of one transfer of the printing paper 7 and the fixing width W of the fixing device 13 become the same, so that the fixing device 13 fixes the toner image once fixed. It does not pass over again, so that excessive fixing can be prevented.

As described above, according to the present embodiment, since the fixing device 13 is integrally connected to the transfer opposing roller 8, the fixing device 13 stops or moves together with the transfer opposing roller 8, and Since it does not stop immediately and moves on the printing paper 7 at a constant speed, an excessively fixed portion or an insufficiently fixed portion does not occur. Further, since the temperature of the fixing unit 13 may be kept constant, the temperature control of the fixing unit 13 is facilitated. Further, the fixing device 13
Is made the same as the width of the developing device 3, so that excessive fixing can be prevented more reliably.

[0021]

As described above, according to the image forming apparatus of the present invention, the toner image carried on the toner image carrier stretched by the plurality of rollers in the direction perpendicular to the conveying direction of the printing paper is transferred to the opposite roller. Is an image forming apparatus of an orthogonal transfer system in which a toner image transferred to the printing paper is fixed by a fixing device by transferring the toner image onto the printing paper in a direction orthogonal to a conveying direction of the printing paper by a fixing member. By being combined with the rollers, the fixing device stands by at a place other than above the printing paper when the printing paper is transported and stopped, and is opposed to only when transferring the toner image carried on the toner image carrier onto the printing paper. Since it moves on the printing paper at a constant speed together with the rollers, there is no occurrence of an excessively fixed portion or an insufficiently fixed portion, and the temperature of the fixing unit may be kept constant at all times. In an advantageous effect that the temperature control of the fixing unit becomes easy is obtained.

Further, since the fixing device has the same fixing width as that of the developing device, the fixing device does not pass over the toner image once fixed again, so that excessive fixing is more reliably performed. This has the advantageous effect of being able to prevent this.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an image forming apparatus according to a first embodiment of the present invention;

FIG. 2 is a configuration diagram showing a conventional image forming apparatus of an orthogonal transfer system.

FIG. 3 is a perspective view of a main part showing a main part of a conventional image forming apparatus of an orthogonal transfer system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Toner image carrier 2 Charging device 3 Developing device 3a Toner 3b Developing roller 3c Toner image 4 Cleaning device 5 Static eliminator 6 Exposure device 7 Printing paper 8 Transfer opposed roller 9 Displacement roller 10 Transfer plate 12 Discharge roller 13 Fixing device 14 Connection Element

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Masashi Ogawa 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yusuke Shiihara 1006 Kadoma Kadoma, Osaka Pref.Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] A transfer roller for transferring a toner image carried on a toner image carrier stretched in a direction perpendicular to a direction in which the printing paper is transported by a plurality of rollers in a direction perpendicular to the direction in which the printing paper is transported; And an image forming apparatus of an orthogonal transfer type wherein the toner image transferred to the printing paper is fixed by a fixing device, wherein the fixing device is connected to the transfer opposing roller by a connecting member. apparatus. 2. The image forming apparatus according to claim 1, wherein the fixing device has a fixing width equal to a developing device width.