JP3069382B2 - Transfer material curling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a transfer material supply device of an image forming apparatus such as a printer or a copying machine, and imparts curl to a transfer material in order to improve the adhesion of the transfer material to a transfer body. The present invention relates to a transfer material curling device.

[0002]

2. Description of the Related Art Conventionally, in an electrostatic image forming method, in a process of transferring an image to a transfer material, a transfer sheet P as a transfer material is used as a transfer body as shown in FIGS. When the transfer paper P is mounted on the transfer drum 3, for example, when the transfer paper P is thick like a postcard or short, the leading end is gripped by a gripper 3a as shown in FIG. Although there is no problem, the rear end is not attached to the outer periphery of the transfer drum 3 at all, so that the front end comes off the gripper 3a during transfer, or the image is unevenly transferred, and color shift occurs in a color image. Problem.

Therefore, the electrostatic attraction force is improved by increasing the transfer output, or a sheet having a strong electrostatic attraction force is attached to the rear end portion of the transfer paper to improve the winding adhesion to the transfer drum. As disclosed in Japanese Patent Publication No. Sho 62-15870, a configuration has been proposed in which a number of rollers are provided around the transfer drum to correct the winding of the transfer paper.

[0004]

However, in the above-mentioned prior art, there is a limit in increasing the transfer output, and in the case of using a sheet having a strong electrostatic attraction,
Although the adsorptivity to the transfer drum is improved, it is necessary to attach and remove the sheet for each transfer sheet and the workability is poor. In the case where a large number of rollers are provided, a roller cleaning device is also required to maintain image quality, and there is a problem that the configuration is complicated and the cost is increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide a transfer material curling apparatus having a simple and inexpensive structure capable of reliably forming a curl for improving the tightness of winding around a transfer material with respect to a transfer material. To provide.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a transfer material feeding means for feeding a transfer material to a transfer material for transferring an image to the transfer material, and to transfer the transfer material to an end of the transfer material before putting the transfer material into the transfer material supply means. In a transfer material curling device for forming a curl for improving the adhesiveness of winding around, a deformation guide portion for imparting curl to an end portion of the transfer material, and movably disposed in the deformation guide portion. This is attained by providing a guide body including a transport guide unit. Specifically, for example, the transport guide portion is configured by a roller driven by a frictional force with the transfer material.

[0007]

The transfer material inserted from the insertion guide portion is curled at the end by the deformation guide portion, pulled out from the insertion guide portion, stored in the transfer material supply means, and fed to the transfer body. In other words, the curl imparting improves the winding adhesion of the transfer material to the transfer body. Further, when the transfer material is fed from the insertion guide portion to the deformation guide portion, for example, the transfer material can be smoothly guided without buckling by the transport guide portion configured by a rollable roller.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram schematically showing an electrophotographic color copying machine according to one embodiment of the present invention. The basic electrophotographic process is the same as that of a known electrophotographic process.

That is, the copying machine 1 comprises a photosensitive drum 2 rotatable in the direction of the arrow shown in the figure and a transfer drum 3 which can move in the same direction and at the same speed as the drum 2 in opposition to the photosensitive drum. 2, an exposing unit 5 is located above the drum 2, and a pre-charging unit 6, a developing unit 7, an erasing unit 8, a cleaning unit 9 and the like are located around the drum 2.
A transfer unit 1 is provided in a portion facing the photosensitive drum 2 inside the printer.
0 indicates a sheet feeding unit 11 in front of the transfer unit 10 in the rotation direction of the transfer drum 3, and a separation unit 12 behind the transfer unit 10 in the rotation direction of the transfer drum 3.

In the exposure section 5, an optical system having a light source and a plurality of reflecting mirrors reciprocates in a scanning direction with respect to the document table 14 with respect to the document table 14 made of a transparent body fixed to the upper surface of the main body. A plurality of exposure scans are performed on the document on the document table 14, and the reflection from the document is color-separated by the filter 15 and guided to the photosensitive drum 2 during each scan.

The pre-charging unit 6 is located in front of the exposure position in the rotation direction of the photosensitive drum 2, and uniformly charges the photoconductive layer of the photosensitive drum 2 with a predetermined polarity. .

On the other hand, the developing section 7 is located behind the exposure light irradiation position in the rotation direction of the photosensitive drum 2, and is a complementary color of three primary colors, cyan and magenta, separated by the filter 15 of the exposure section. , Three developer tanks containing the developers of the respective colors, and a developer tank containing the black developer, are installed near the outer periphery of the photosensitive drum 2.

The erasing section 8 has a light amount capable of removing charges remaining on the background of the photosensitive drum 2 in order to remove the developer adhering to the non-image area on the photosensitive drum 2 after development. And emit light.

The cleaning unit 9 is located behind the position facing the transfer drum 3 in the direction of rotation of the photosensitive drum 2, and is electrically charged between the charge on the photosensitive drum 2 by the charge elimination charger. The residual developer on the photosensitive drum 2 in which the sum is set is removed by a cleaning roller having the same structure as the developing sleeve described above, and the residual charge on the photosensitive drum 2 is removed by a quenching lamp. I do.

On the other hand, the transfer section 10 of the transfer drum 3
Has a charger 17 facing the photosensitive drum 2 across the peripheral wall of the transfer drum 3 inside the transfer drum 3 provided so as to be able to contact and separate from the photosensitive drum 2, and the transfer drum 3 At the time of the transfer approaching the drum 2, charging of a polarity opposite to that of the developer is performed. A paper feed unit 11 is located in front of the transfer unit 10 in the rotation direction of the transfer drum 3.

The separating section 12 includes a swingable separating claw located behind the transfer section 10 in the rotation direction of the transfer drum 3 and a moving direction of the sheet separated from the transfer drum 3 by the separating claw. It has a transport belt and a separation charger located behind the separation claw, and transports the sheet separated from the transfer drum 3 to the fixing device 16. The fixing device 16 includes a heating roller and a pressure roller that rotates in contact with the heating roller. The fixing device 16 thermally fixes an image on the sheet while nipping and conveying the sheet, and discharges the sheet.

The paper supply section 11 is provided on each of a plurality of conveyance rollers 20, a guide plate 21, a paper supply cassette (two in this example) 22 constituting transfer material supply means, and each paper supply cassette 22. And a feed roller curling device main body 24 to be described later, which is provided on the side of the paper feed cassette 22.

FIG. 2 is a perspective view of a main part of the curling device main body, and FIG. 3 is a longitudinal sectional view of the curling device main body. The curling device main body 24 includes an opening 25 through which the transfer paper P is put in and out, an insertion guide 26 having a horizontal path that does not deform the transfer paper P, and a curving path following the insertion guide 26. The transfer sheet P has a guide body 28 integrally formed with a deformation guide section 27 that forms a curl C at an end of the transfer sheet P. A reciprocating roller 29 for performing insertion and withdrawal is provided. Further, a groove 30 is formed in the insertion guide portion 26 so as to extend toward the outside, and a plate-shaped stopper which is a transfer material insertion position regulating means movable in the transfer paper insertion direction (the direction of arrow X) is formed in a deep portion of the groove 30. 31 are provided.

The stoppers 31 are provided on both sides of the upper and lower insertion guides 26 or at least one of them. Further, although various types of installation structures to the insertion guide portion 26 are conceivable, in this example, a screw 34 fixed to the insertion guide portion 26 is inserted into a long hole 33 provided in the stopper 31.
2 shows a structure for holding the connector in a loose fit.

Further, as shown in FIG.
A roller (conveyance guide portion) 36 rotatably supported by a shaft 35 is disposed therein, and is abutted against the leading end of the transfer paper P conveyed through the insertion guide portion 26 and rotates by itself. It guides the transfer paper P smoothly.

The guide member 28 moves the transfer paper P
In order to improve the adhesiveness of winding around the transfer drum 3,
It is used when the curl C is formed at the end of the transfer paper.
For example, when the transfer paper P which needs to be curled, such as thick paper or a postcard, is inserted from the reciprocating roller 29, the reciprocating roller 2
By the forward rotation of 9, the transfer paper P is guided from the opening 25 to the insertion guide portion 26, and further conveyed to the deformation guide portion 27 while being guided by the rollers 36 so as not to cause deformation such as buckling. Thereafter, by reversing the reciprocating roller 29,
The transfer paper P is pulled out to the outside, and as shown in FIG. 5, a state in which the curl C is attached to the rear end of the paper supply unit 11 in the paper supply direction (the direction of arrow A).

Since the reciprocating roller 29, which is a means for taking in and out the transfer paper P, and the operator's finger in the manual operation can be put in the groove 30, the transfer paper P is transferred to the deformation guide portion 27. The transfer paper P is inserted while being held by the reciprocating roller 29 or a finger, and there is no buckling or the like of the transfer paper P due to the action of the roller 36, so that smooth insertion and withdrawal become possible. Further, by controlling the position (the degree of insertion) of the transfer sheet P to be inserted into the deformation guide portion 27 by the stopper 31, the curling position of the transfer sheet P which varies depending on the paper quality can be controlled. The regulation of the insertion position is shown in FIG.
As shown in the perspective view of the main part of another embodiment of the guide body shown in FIG. 7, an insertion position regulating mark 32 is formed on the periphery of the groove 30 and the mark 32 can be used as a reference. . In the configuration shown in FIG. 4, a mark 32a for thin paper and a mark 32b for thick paper are formed.

The transfer paper P with the curl is stored in the paper supply cassette 22 and fed as shown in the explanatory view of FIG. 6, and the transfer drum 3 receives the transfer paper P as shown in FIGS. 7A and 7B. As shown in the figure, the front end is gripped by the gripper 3a, and the rear end with the curl C is in close contact with the outer periphery of the transfer drum 3 and is transferred by the photosensitive drum 2.

The transfer paper P is passed through the opening 25 of the guide body 24.
Can be manually operated by an operator without using the reciprocating roller 29. In this case, the front end of the transfer paper P is pinched and the transfer paper P
By moving the rear end into and out of the opening 25, the rear end is curled.

[0025]

As described above, claims 1 to 4
According to the invention described above, the transfer material inserted from the insertion guide portion is smoothly guided to the deformation guide portion by the transport guide portion, so that the transfer material is curled without buckling. And the adhesion to the transfer member can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing a copying machine to which the present invention is applied.

FIG. 2 is a perspective view of a main part of the curling device according to one embodiment of the present invention.

FIG. 3 is an overall vertical sectional view of the curling device.

FIG. 4 is a perspective view of a main part of another embodiment of the curling device.

FIG. 5 is a perspective view of the transfer sheet with a curl.

FIG. 6 is an explanatory diagram illustrating a storage state of transfer paper.

FIG. 7 is an explanatory diagram illustrating a state of close contact of a transfer sheet with a transfer drum.

FIG. 8 is an explanatory diagram illustrating a state of close contact of a transfer sheet with a conventional transfer drum.

[Explanation of symbols]

 Reference Signs List 3 transfer body 22 transfer material supply means 24 transfer material curling device main body 26 insertion guide section 27 deformation guide section 28 guide body 29 means for retrieving and removing transfer paper (reciprocating roller) 36 transport guide section P transfer material

Claims (4)

(57) [Claims] 1. An image forming apparatus comprising: a transfer material supply unit for feeding a transfer material to a transfer material for transferring an image to the transfer material; In a transfer material curling device for forming a curl for improvement, a guide including a deformation guide portion for imparting curl to an end portion of the transfer material and a transport guide portion movably disposed in the deformation guide portion. An apparatus for curling a transfer material, comprising a body. 2. The transfer material curling device according to claim 1, wherein the conveyance guide portion is driven by a frictional force between the transfer guide portion and the transfer material. 3. The transfer material curling device according to claim 1, wherein the transport guide portion is constituted by rollers whose both ends are rotatably supported. 4. The transfer material curling device according to claim 3, wherein the roller constituting the transport guide has at least a length in a width direction of the transfer material. .