JP2002046920A - Sheet guide means at sheet discharge part in electrophotographic printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate problems of deflected stack of printed sheets, or attachment of them to a plastic sheet guide member due to static electricity by electrification of the plastic sheet guide member and the printed sheets by friction when the printed sheets get in contact in the plastic sheet guide member installed for improving arrangement performance. SOLUTION: This guide member at a sheet discharge part to discharge the printed sheets is composed as a conductive sheet type guide member of plastic of thickness of 0.25-0.1 mm, and it is grounded, so that static electricity by friction is not generated in getting in contact, and that static electricity of the sheets generated during carry is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to paper guide means for a paper discharge section of an electrophotographic printing apparatus.

[0002]

2. Description of the Related Art In an electrophotographic printing apparatus which prints characters and images created and processed by a computer, an electrostatic latent image is developed, and the electrostatic latent image is transferred and fixed in order to collect printed paper. A paper compartment is attached. The paper output storage section is attached to the top or side of the printer and can be used to store discharged paper under its own weight. There are devices and the like that are integrated in the shape storage unit. The latter is often used in laser printers that perform continuous mass printing. With the recent increase in printing speed,
The discharge speed is also high. Correspondingly, a contrivance has been made to accumulate printed sheets with good alignment without jamming. As means therefor, there is a method of providing a guide and a stopper.

[0003] As shown in Fig. 3, a sheet-like guide member made of a thin elastic plastic (for example, polyester) is attached, and the discharged printed paper is brought into contact with the sheet and pushed downward by a moderate force by elastic force. Thereby, the alignment is improved without scattering the printed paper.

[0004]

In the conventional method, when the printed sheet comes into contact with the plastic sheet guide member during discharge, the plastic sheet guide member and the printed sheet are charged by friction. For this reason, the printed paper is attracted by the static electricity charged to the plastic sheet guide member, and the printed paper is displaced and accumulated to disturb the alignment, or is stuck to the plastic sheet guide member and is not normally accumulated. There is a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to release static electricity generated upon contact with a printed sheet, prevent the sheet guide member made of plastic from being charged, and eliminate the deviation of the printed sheet due to the static electricity.

[0006]

The above object can be attained by using a conductive sheet-like guide member provided with a carbon coating on the guide member to prevent electrification.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, taking a laser printer as an example.

FIG. 1 is a schematic diagram showing a main body of an electrophotographic apparatus such as a laser printer and a paper discharge unit. The image forming means of the electrophotographic apparatus has a generally known configuration.

In the electrophotographic apparatus main body, although not shown, a printed paper 11 on which an electrostatic latent image such as a character or an image written on a photoreceptor is developed by a laser, and transferred and fixed is processed. The sheet is conveyed to the paper discharge section. And in the paper output section,
The printed paper 11 passes through the paper guide 1 and is transported by the idler roller 2. Then, the printed paper 11
Contacts the conductive sheet-shaped guide member 4 attached to the guide member 3 with the conductive aluminum foil tape 5. The conductive sheet-like guide member 4 has elasticity and hangs down by its own weight, and the printed sheet 11 is pushed down by an appropriate force of the sheet by its elastic force. At this time,
The tray 10 moves up and down according to the number of sheets stacked, and the position from the top sheet 12 stacked is controlled. Next, the printed paper 11 passes between the press wire 7 and the tray 10, is conveyed by the floating paddle 8 for further adjusting the alignment, hits the retract stopper 9, and
Will be integrated. The press wire 7 moves up and down with the force of sending the printed paper 11 and maintains the alignment. The above operation is performed continuously.

Conventionally, since the sheet guide member 13 made of an insulating material is made of plastic, the printed paper 11 and the sheet guide member 13 made of plastic are charged by static electricity generated at that time, and the printed sheet 11 is made of a plastic sheet. It stuck to the shape guide member 13 or shifted. In the present invention, since a plastic sheet (for example, polyester or the like) having a carbon coating of 8 μm is used and grounded, no static electricity is generated, and even if the printed paper 11 is charged during transportation, Static electricity is removed by transmitting and escaping the ground sheet 6 attached to the conductive sheet guide 4 from the conductive sheet guide member 4 and grounded, thereby improving the alignment of the printed paper 11 and enabling stable integration.

It has been found by experiments that the conductive sheet-like guide member 4 peels off if the carbon coating is less than 3 μm. When the coating is peeled off, conductivity cannot be maintained and static electricity is generated. Then, the printed paper 11 sticks or shifts to the conductive sheet-shaped guide member 4 from which the coating has been peeled off. However, in the present invention, since the coating is 3 μm or more, the coating is not peeled off, the conductivity is maintained, and stable integration is enabled.

[0012]

According to the present invention, an excellent effect of eliminating static electricity generated upon contact with printed paper, eliminating static electricity charged during conveyance, eliminating deviation of printed paper, and improving alignment. Have.

[Brief description of the drawings]

FIG. 1 is a structural diagram showing one embodiment of a paper guide unit of a paper discharge unit of the present invention.

FIG. 2 is an enlarged view of a guide member of a paper guide unit of a discharge unit according to the present invention.

FIG. 3 is an enlarged view of a guide member of a conventional paper guide unit of a discharge unit.

[Explanation of symbols]

1: paper guide, 2: idler roller, 3: guide member, 4: conductive sheet guide member, 5: conductive aluminum foil tape, 6: ground sheet, 7: press wire, 8:
Floating paddle, 9: retract stopper, 1
0: tray, 11: printed paper, 12: top paper, 1
3: Plastic sheet guide member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Manabu Suzuki 1060 Takeda, Hitachinaka-shi, Ibaraki Prefecture Inside Hitachi Koki Co., Ltd. ) Inventor Hidehisa Shibasaki 1060 Takeda, Hitachinaka-shi, Ibaraki F-term in Hitachi Koki Co., Ltd.

Claims (3)

[Claims] A guide member that contacts a printed sheet and presses down and aligns the printed sheet with an appropriate force by an elastic force in a discharge section of an electrophotographic printing apparatus that accumulates the printed sheet. 0.25
A sheet guide means for a sheet discharge section, which is a conductive sheet-like guide member having an elasticity of about 0.1 mm, and wherein a contact portion of the conductive sheet with the sheet is grounded. 2. A sheet guide means for a sheet discharge section, wherein the conductive sheet-shaped guide member is made of plastic having a surface coated with carbon. 3. A sheet guide means for a sheet discharge section, wherein a thickness of a carbon coat is 3 μm or more in the conductive sheet-like guide member.