JPS638157A - After-separation conveyor - Google Patents

Abstract

PURPOSE:To keep off any trouble in conveyance, by installing a roller, having plural kick-out projections on the circumferential surface, in the point midway in where the paper transferred with an image from an image bearer is separated from this image bearer and conveyed, and giving conveying force to the paper. CONSTITUTION:The paper P transferred with an image by a transfer charger 11 in contact with an image bearer drum 12 is separated from this image bearer 12 and conveyed by a conveyor belt 15, heading for fixing rollers 20a and 20b. In and around the spot where the paper P is separated from the image bearer 12, there is provided with a kick-out roller 30 having plural kick-out projections 31 and kick-out parts 31a in the circumderential direction. The kick-out roller 30 is rotated in an arrow direction, and a rear end of the paper P is pushed by the kick-out part 31a. With this constitution, positive conveying force is given to the paper P, and thereby any slip in the paper P and its admission failure into these fixing parts 20a and 20b are all prevented from occurring.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image forming apparatus such as a copying machine or a printer, and particularly to a post-separation conveying means for conveying sheets 1 to 10 separated from an image carrier. It is related to.

[Prior Art and Problems] A diagram of a conventional device is shown in FIG. The relationship between the post-separation conveyance roller 13 and the conveyance belt 15 is such that a conveyance guide 21 is provided between them, and after the transfer, the separated sheet material P is conveyed and the leading edge is bitten by the fixing rollers 20a and 20b. Since the sheet material P is along the conveyance guide 21 and the conveyance belt 15, the shock of the plunge into the fixing rollers 20a and 20b is transmitted to the rear end of the sheet material P as shown by the arrow, and the sheet material is There was a problem that P was affected and transfer misalignment occurred.

Furthermore, since the conventional post-separation and withdrawal roller 13 has a circular cross-sectional shape, the length of the sheet material P is longer than that of the fixing rollers 20a and 2.
When the distance between the image bearing drum 12 and the image 11 is longer than the distance between the image bearing drum 12 and the image bearing drum 12, the fixing roller 20a is pushed out by the image bearing drum 12.
However, if the length of the transfer paper is short or the paper is stiff, the fixing density guide 19, the fixing roller 20a,
When the leading edge of the sheet material hits 20b, the sheet material P slips on the conveying roller 13 after being separated, and the fixing roller 20a,
There was a drawback that it did not get caught in 20b (Fig. 7).

Furthermore, in the case of thick core size paper such as business cards, cards, postcards, etc., when the rear end of the sheet material P remains on the rear roller 13, the leading edge of the sheet material P is placed on the fixing roller 20a.
, 2Ob, when the fixing roller 2
There were drawbacks such as the paper stopping because it did not enter the nip portions 0a and 20b properly.

[Configuration for Solving Problems] The present invention has been accomplished to solve the above-mentioned problems, and has the following configuration. That is, the post-separation conveying means conveys the sheet material separated from the image bearing member after the image on the image bearing member is transferred in the transfer section, and is located near the downstream side of the separation position in the sheet material conveying direction. It is provided,
This is a post-separation conveying device characterized by having a kicking means having a kicking part on the circumferential surface and moving endlessly to apply a kicking force to the sheet material.

[Example] Fig. 1 is a diagram of the post-separation conveyance device according to the invention, and Fig.
The figure is a sectional view of a copying machine using this. An image is formed on the surface of the sheet material P between the image carrier drum 12 and the transfer charger 11, and the electric charge is removed by the charge eliminating needle 24, and the image is removed from the image carrier drum 12 by 1 minute! III. Thereafter, the rear end of the sheet material P is pushed by the kicking roller 30, passes through the conveyor belt 15, the fixing entrance guide 19-, and is fixed by the fixing rollers 20a and 20b.

In the post-separation conveyance device of this embodiment, the top of the h-cutting roller 30 is connected to the roller 2 that supports the conveyance belt 15.
It is desirable that the height be about 6 to 15 mm higher in the vertical direction than the top of 3a. Further, as shown in FIG. 2, the cross-sectional shape of the kicking roller 30 has a kicking protrusion 31 on the circumferential surface, and at its front end in the direction of rotation shown by the arrow, a kicking part 31a that pushes the rear end of the sheath material. There is.

As shown in FIG. 5, by setting the level difference H between the top of the kicking roller 30 and the top of the roller 23a that supports the conveyor belt 15 to 6 to 15 mm, as shown in FIG. When the material P enters between the fixing rollers 20a and 20b, the shock is generated by the kicking roller 30 and the conveyor belt 15.
It is absorbed by the loop portion of the sheet material P formed between the sheet material P, and has the effect of preventing transfer displacement due to shock of the sheet material P entering the fixing rollers 20a and 20b.

Further, by providing a kicking portion 31a on the circumferential surface of the kicking roller 30, the rear end of the sheet material is pushed and the sheet material P such as thick small size paper hits the fixing entrance guide 19 and the fixing rollers 20a and 20b and stops. It is possible to prevent this from happening. (FIG. 5) Also, regarding the positional relationship between the kicking roller 30 and the image carrier tram 12, the line connecting the center of curvature +2a of the image carrier drum 12 and the charging wire 11a of the transfer charger 11 is the image carrier drum. It is desirable that the top of the kicking roller 30 be located at a position 0 to 3 mm away from the image carrier drum 12 side from the tangent M that touches the image carrier drum 12 at a point T that intersects on the circumference of the image carrier drum 12.

[Effects of the Invention] As explained above, by adopting the structure of the invention, a reliable conveying force is applied to the separated sheet material, and the sheet material does not slip on the conveying means, or the fixing roller on the downstream side It is possible to solve the inconvenience of not being able to enter a pair.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a post-separation conveyance device using the present invention;
Fig. 2 is a cross-sectional view of the fitted one-out roller, Fig. 3 is a cross-sectional view of a copying machine using the present invention, Fig. 4 is an explanatory diagram showing the state in which the sheet material forms a loop, and Fig. 5 is a thick An explanatory diagram showing a state in which sheet material is pushed out, and FIGS. 6 and 7 are cross-sectional views showing a conventional separation and conveyance device. 11-m-Transfer charger 12--11 Image carrier drum 15-m-Transport belt 20a, 20b--Constant fixing roller 24-m-Charge removal needle 30-11 Kick-out roller 31-11 Kick-out protrusion 31a--Kick out section

Claims (1)

[Scope of Claims] Post-separation conveying means for conveying a sheet material separated from the image bearing member after the image on the image bearing member is transferred in the transfer section, the sheet material conveying unit at the separation position. 1. A post-separation conveyance device characterized by having a kicking means provided near the downstream side in the direction, having a kicking part on the circumferential surface and moving endlessly to apply a kicking force to the sheet material.