JP2001346000A - Image reading device - Google Patents

Abstract

(57) An object of the present invention is to provide an image reading device capable of preventing fine particles of paper powder and toner from adhering to a reading glass and a platen roller and reading an image with good image quality. An image reading apparatus includes a reading glass facing an optical scanning system for reading a document, and a platen roller facing the reading glass. Then, the surface of the reading glass 5 is conductively grounded, and the platen roller 7 is brought into contact with the grounded neutralizing brush 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus such as a scanner and, more particularly, to an image reading apparatus which can read a good image without being affected by scattering of paper dust or toner on a sheet at an image reading section. It relates to a reader.

[0002]

2. Description of the Related Art Among scanners, an original moving scanning type supplies an original sheet mounted on a hopper or the like to a reading line, and the original is scanned by an optical scanning unit when passing through a reading glass arranged on the reading line. The image is read.
The reading glass is transparent and is disposed corresponding to the optical scanning unit, and is incorporated so as to face the conveyance line of the document sheet. A platen roller that guides the original paper is disposed at a position facing the reading glass.

In such a document moving scanning type scanner, an image is read by an optical scanning unit and converted into data while a document sheet is supplied to a transport line and passes between a reading glass and a platen roller.

[0004]

However, since the manuscript paper is supplied at a relatively high speed, paper dust is easily scattered from the manuscript paper and minute particles of toner on the surface of the manuscript paper are easily peeled off. Such fine particles of paper powder and toner adhere to the surface of the reading glass or platen roller due to static electricity. For this reason, when an image is read from a document sheet, black lines or white spots appear in the read image due to the influence of the fine particles of the paper dust and the toner, which causes a great decrease in the read image quality. .

As described above, in the conventional image reading apparatus,
Inevitably, fine particles of paper powder and toner adhere to the reading glass and the platen roller, and the image quality of the read image deteriorates.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image reading apparatus capable of preventing fine particles of paper dust and toner from adhering to a reading glass and a platen roller and reading an image with good image quality.

[0007]

According to the present invention, a reading glass facing an optical scanning system for reading the original is arranged in the middle of a transport path on which the original is transported, and a platen arranged to face the reading glass. In an image reading apparatus provided with a roller, the surface of the reading glass is conductively grounded, and a grounding neutralizing brush is brought into contact with the platen roller.

According to the present invention, there is provided an image reading apparatus capable of preventing fine particles of paper dust and toner from adhering to a reading glass and a platen roller and reading an image of good quality.

[0009]

According to a first aspect of the present invention, a reading glass facing an optical scanning system for reading the original is arranged in the middle of a conveying path through which the original is conveyed, and is arranged so as to face the reading glass. An image reading device provided with a platen roller, wherein the surface of the reading glass is conductively grounded, and the platen roller is brought into contact with a grounded neutralizing brush. Since the glass surface is conductive and grounded, there is no electrostatic attraction of paper dust and toner particles, and the platen roller is also grounded by a neutralization brush, thus eliminating electrostatic attraction of paper powder and toner particles as well. It has the effect of being able to.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view showing a main part of an image reading apparatus according to the present invention.

In FIG. 1, a pair of guide frames 1a and 1b to which original sheets are supplied from a hopper (not shown) on which original sheets are mounted in the direction of the arrow in FIG. A pair of transport rollers 2a, 2b is arranged along the guide frames 1a, 1b. Also,
Downstream of the guide frames 1a, 1b, the transport rollers 3a,
3b are arranged, and the original paper is
The paper is supplied in the paper discharge direction while being nipped by the pair of a and 3b.

An optical scanning unit 4 is disposed above the guide frames 1a and 1b, and a reading glass 5 is disposed on the guide frame 1a in correspondence with the optical path of the optical scanning unit 4. Light source 6a, 6b
Is provided. Below the reading glass 5, a platen roller 7 that contacts and feeds the document paper is arranged.

FIG. 2 is a longitudinal sectional view showing a main part of the reading glass 5 and the platen roller 7.

The surface of the reading glass 5 is subjected to conductive treatment, and the conductive treated surface is formed of a metallic guide frame 1a.
It is conducting. The guide frame 1a is electrically connected to a chassis (not shown) built in the main body of the image reading apparatus and is grounded. The conductive treatment of the surface of the reading glass 5 is as follows.
This is performed by forming a transparent metal film 5a on the surface by a vacuum evaporation method or a CVD method.

The platen roller 7 is made of metal, and a frame 8 which is electrically connected to the chassis of the main body of the image reading apparatus and is grounded is disposed in the vicinity of the metal. Have been. The leading end of the charge removing brush 9 contacts the peripheral surface of the platen roller 7, and the charge carried by the platen roller 7 is released to the ground by the charge removing brush 9.

In the above configuration, the original paper P from the hopper is fed between the guide frames 1a and 1b in the direction of the arrow as shown in FIG. When passing between the reading glass 5 and the platen roller 7, the optical scanning unit 4 reads an image on the document sheet P.

Since the surface of the reading glass 5 is grounded via the guide frame 1a after the surface of the reading glass 5 is electrically conductive, the charge caused by static electricity on the surface of the reading glass 5 is quickly released to the ground side. Therefore, fine particles of paper dust and toner generated when the document paper P passes do not adhere to the reading glass 5 due to static electricity, and the platen roller 7 is also grounded by the neutralizing brush 9. Similarly, there is no adhesion of fine particles of paper powder or toner due to static electricity. As described above, even when the document paper P passes, the reading glass 5 and the platen roller 7
There is no adhesion of paper dust or toner particles to the image, no black line or white spots appear on the read image, and good image reading becomes possible.

[0019]

According to the present invention, since paper dust and toner particles do not adhere to the reading glass and platen roller due to static electricity, the original image can be read clearly, and good image reading can be performed without deterioration in image quality due to foreign matter adhesion. .

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a main part of an image reading apparatus according to the present invention.

FIG. 2 is a longitudinal sectional view showing a main part of a reading glass and a platen roller part.

[Explanation of symbols]

 1a, 1b Guide frame 2a, 2b Transport roller 3a, 3b Transport roller 4 Optical scanning unit 5 Reading glass 5a Metal film 6a, 6b Light source 7 Platen roller 8 Frame 9 Static elimination brush P Original paper

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Junichi Suematsu 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. (Reference) 2H108 AA14 CB01 JA02 5B047 AA01 BA01 BB02 BC14 BC30 5C072 AA01 BA20 LA18 NA10 XA01

Claims (1)

[Claims] 1. An image reading apparatus comprising: a reading glass facing an optical scanning system for reading an original; and a platen roller disposed opposite to the reading glass. An image reading apparatus wherein the surface of the reading glass is conductively grounded, and the platen roller is brought into contact with a grounded neutralizing brush.