JPH04159943A - Paper feeder for image forming device - Google Patents

Abstract

PURPOSE:To reduce generation of erroneous feeding of paper by moving, a specified distance along the face of recording paper, a static electricity removing means brought into contact with the uppermost part of a paper feed cassette through operation of a static electricity removing means driving system by a control part every time when recording paper sheets are fed one by one. CONSTITUTION:A static electricity removing means 120 and a drive system therefor are arranged just on the upper part of a paper feed tray 109. The means 120 grounded to an image forming device main body is fixedly locked at a proper position of a wire 130 laid endlessly by pulleys 131, 131, and advanced or retreated to a terminal position E from a home position while driven to rotate by a specified amount by a stepping motor 132. The sweep operation is set by a program of a control part so that recording paper is fed one by one. The means 120 removes static electricity on the recording paper P on the tray 109 while moves to the reverse direction to the paper feed direction at the time point when the rear end of the paper P remains behind a pickup roller 125 by a specified length.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a paper feeding device that can eliminate paper feeding failures caused by charging of recording paper.

(Prior Art) Image forming apparatuses such as copying machines and printers take out recording sheets one by one from a paper feed cassette, feed them to an image forming section centered on a photoreceptor, and print them onto the recording sheets. Transfer toner image,
A series of image forming steps are carried out by discharging the image after it has been fixed.

By the way, in machines such as high-speed copying machines that are equipped with a paper feeding mechanism that allows recording paper to be fed at short intervals, if the recording paper stored in the cassette is continuously fed, the previously fed recording paper will be Feeding of the succeeding recording paper is started before static electricity generated on the succeeding recording paper due to friction with the paper is naturally discharged and removed. Therefore, adhesion due to static electricity occurs between the subsequent recording paper and the recording paper immediately after it, and paper feeding failures such as jams and non-feeding are likely to occur.

(Object of the Invention) The present invention has been made in view of the above, and an object of the present invention is to provide a paper feeding device that prevents recording sheets from coming into close contact with each other due to charging, thereby reducing the occurrence of paper feeding failures. The purpose is

(Structure of the Invention) In order to achieve the above object, the present invention provides an image forming apparatus equipped with a paper feeding mechanism that takes out recording paper stored in a paper feeding cassette from the top and feeds the paper to an image forming section. The apparatus includes a static eliminator that contacts the uppermost recording paper to remove static electricity, a static eliminator drive mechanism that moves the static eliminator along the surface of the recording paper, and a paper feeding mechanism that feeds one recording paper. The present invention is characterized by comprising a control section that operates the drive mechanism to move the charge eliminating means a predetermined distance along the surface of the recording paper each time.

Further, another embodiment of the present invention is characterized in that a snow removal brush is used as the static eliminating means.

Furthermore, another embodiment of the present invention is characterized in that the static elimination brush is grounded.

Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a schematic diagram illustrating the configuration of a copying machine to which the paper feeding device of the present invention is applied. There is.

The copy processing unit A includes an automatic document feeder 101 that automatically arranges a plurality of set originals at a predetermined value 1, a lamp 102 and a mirror 103 that optically scan the documents sequentially placed at predetermined positions by the automatic document feeder 101. .104 and lens 105, and the optical image information from the optical system is exposed to 7%! The photoreceptor belt 106 that forms an image and the photoreceptor bell l-106 are
A charger 107 that performs M1i processing, a developer 108 that develops an electrostatic latent image formed after exposing the charged photoreceptor belt 106, and feeds the image developed by the developer 108. The record conveyed from tray 109! ! A transfer device 110 that transfers onto paper, a cleaning section 111 that cleans the photoreceptor belt 106 after a series of copying processes in preparation for the next copying process, and a fixing device 112 that fixes the transferred image transferred onto the recording paper. An output tray 113 that outputs and stacks the recording paper conveyed after the fixing process, a detection unit 118 (for example, a counter) that detects the loading amount of the output tray 113, and a paper feed cassette (
It is comprised of paper feeding mechanisms 115a to 115c, such as feed rollers, which pick up the recording paper on a paper feeding tray 109, which consists of a tray, etc., and feed it to a transfer device 110.

Next, the large-volume paper feed unit B has the same configuration as the paper feed mechanism including the paper feed tray l○9 described above, and includes a storage unit 114 that stores a large amount of recording paper in order to cope with the large consumption of recording paper. The paper feeding mechanism 115d conveys the recording paper stored in the storage section 114 in accordance with the transfer processing timing of the copy processing section A.

In this embodiment, a static eliminating brush (static eliminating means) 12o is provided directly above each paper feed tray 109, and a driving mechanism 12 for the static eliminating brush is provided.
The structure in which 1 is arranged is characteristic.

Next, the recording paper post-processing section C transfers the ejected recording paper to a predetermined tray section 11 after the copy processing section A has finished a series of copying processes.
6, and a detection unit 119 (for example, a counter) that detects the loading amount of the tray unit 116.

FIG. 2 is an explanatory diagram showing the operating principle of the static elimination brush 120, and the brush 120, which is grounded to the main body of the image forming apparatus, has a drive mechanism consisting of an endless wire mechanism as shown in FIG. 121, it is configured to be able to freely move forward and backward along the paper feeding direction.

After the recording paper P is taken out by the pickup roller 125, it is guided to the nip portion between the separation roller 126 and the conveyance roller 127, and is fed to the image forming section.

The static eliminating brush 120 has a rear end portion of the preceding recording paper P1 that is a predetermined length (for example, 5 to 20 m) longer than the pickup roller 125.
m) When it remains at the rear, it moves in the opposite direction to the paper feeding direction as shown by fbl, and charges are removed from the recording paper P on the paper feeding tray 109.

The drive mechanism shown in FIG. 3 uses pulleys 131 and 131 to fixedly fix the neutralizing brush 120 to the appropriate position of the wire 130 stretched in an endless manner, and rotates one of the boots by a predetermined amount by a stepping motor 132. By driving, the static eliminating brush 120 is advanced and retreated from the home position HP shown by the dotted line in FIG. 2 (bl) to the terminal position E shown by the solid line.

A program in a ROM constituting a control section (microcomputer) is set so that the sweeping operation by the static eliminating brush is executed every time a sheet of recording paper is fed.

This sweeping action of the static elimination brush makes it possible to forcibly remove static electricity from the recording paper P on the paper feed tray 109, thereby preventing the occurrence of paper feeding failures due to electrostatic adhesion between the recording papers. It becomes possible. In particular, it is possible to improve paper feeding performance by eliminating frictional charging and spontaneous discharge defects that tend to occur in image forming apparatuses with short paper feeding intervals, such as high-speed copying machines.

If a static elimination brush is used as the static elimination means, it is possible to simplify the device configuration, reduce costs, and facilitate maintenance. Furthermore, the static elimination performance can be improved by grounding the static elimination brush to the device main body side.

In the above embodiment, a static eliminating brush is used as an example of the static eliminating means, but static eliminating means other than the brush, such as a static eliminating pad, a static eliminating roller, etc., can also be used.

(Effects of the Invention) As described above, according to the present invention, it is possible to reduce the occurrence of paper feeding failures by preventing the occurrence of 3rd place between recording sheets due to charging between recording sheets and faulty discharge of charged recording sheets. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the overall configuration of an image forming apparatus to which the present invention is applied; FIG. 2 is an explanatory diagram showing the operating principle of the static elimination brush; and FIG. It is a diagram. 101...Automatic document feeder l○9...Paper feed tray 115a-115c...Paper feed mechanism 120...Static elimination brush 121...Drive mechanism 131...Pulley 1
32...Stepping motor

Claims (3)

[Claims] (1) In an image forming apparatus equipped with a paper feeding mechanism that takes out recording paper stored in a paper feeding cassette from the top and feeds the paper to an image forming section, the image forming apparatus contacts the top recording paper. a static eliminator for removing static electricity; a static eliminator drive mechanism for moving the static eliminator along the surface of the recording paper; 1. A paper feeding device for an image forming apparatus, comprising: a control section for moving means by a predetermined distance along the surface of the recording paper. (2) The sheet feeding device for an image forming apparatus according to claim 1, wherein a static eliminating brush is used as the static eliminating means. (3) The paper feeding device for an image forming apparatus according to claim (2), wherein the static elimination brush is grounded.