JP2551522Y2 - Document reading device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading apparatus such as a facsimile machine, a copying machine, and a scanner.

[0002]

2. Description of the Related Art A facsimile apparatus will be described as an example of a document reading apparatus. FIG. 2 shows the configuration of a facsimile apparatus, where 1 is a document set on a platen,
Denotes a feed roller, and 3 denotes a separation roller. The feed roller 2 and the separation roller 3 cooperate to separate and feed the document 1 one by one. Reference numerals 4 and 5 denote conveying rollers, which convey the fed document. 6 is a contact glass, 7 is a light source,
Illuminates the document passing over the contact glass. The light reflected from the document surface is guided by the mirror 8 and
An image is formed on the reading sensor 10 by the reading sensor 10, and the reading sensor 10 photoelectrically converts the read image to read a document image.

The receiving and recording section includes a platen roller 12 for transporting the thermal recording paper fed from the roll paper 11, a thermal head 13 for recording based on a received signal, and a cutter 14 for cutting the recorded paper for each page. And so on.

[0004] In a conventional facsimile apparatus and the like, a fluorescent lamp is used as the light source 7, but recently, it has been replaced with a Xe lamp in terms of cost and optical characteristics.

However, this Xe lamp has a small tube diameter of about 6 mm, and is therefore preferable in terms of miniaturization. However, since the light amount is as small as 1/10 or less of that of a fluorescent lamp, and further, the tube diameter is small. Warpage is likely to occur due to external force or the like. Therefore,
In order to compensate for the insufficient light amount, it is necessary to bring the Xe lamp itself close to the document surface and to precisely position the Xe lamp so that the distance between the Xe lamps is equal over the entire length of the lamp.

More specifically, the light intensity of the Xe lamp is about 10,000 Lx max when the distance from the center of the lamp to the document surface is 8 mm. On the other hand, in the case of a fluorescent lamp, the light intensity is 100,000 Lx or more, and the illuminance distribution (flatness of illuminance) in the longitudinal direction does not change much even if the distance between the tube and the document surface slightly varies. For example, even if it changes 1,000 Lx with a distance difference of 1 mm, it will be 1
% Change, whereas the Xe lamp is 1
It will be 0% change. With this alone, the white waveform flatness (white output flatness of the CCD) changes by 10%,
The tolerance of other parameters affecting the flatness will be stricter.

On the other hand, as shown in FIG. 3, a conventional method of mounting a Xe lamp mounts a socket portion 17 of a Xe lamp 16 on a base member 15, mounts a guide plate 18 thereon, and mounts the socket portion. The contact glass 6 was attached to the guide plate 18.

[0008]

According to the above-mentioned conventional mounting method, another member, that is, a socket portion 17, is provided between the Xe lamp 16 and the contact glass 6, that is, the original surface passing in contact with the upper surface thereof. The guide plate 18 is interposed, and the interval varies due to their tolerance.

The present invention solves such a problem of the prior art, and enables accurate positioning without influence of other members between the Xe lamp and the contact glass as much as possible. It is an object to provide a document reading device.

[0010]

In order to achieve this object, the present invention has a structure in which a socket of a light source and a contact glass are integrally held together with the light source.

[0011]

According to the above construction, the light source, that is, the Xe lamp, and the contact glass are integrally held in the same socket, so that the distance between the two can be made constant. Can be made uniform.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of the present invention, in which 6 is a contact glass, 16 is a Xe lamp as a light source for illumination,
7 is a socket part. Here, contact glass 6
Is fixed to the socket portion 17 in advance with a certain interval from the Xe lamp 16 and fixed.

In order to mount it on the reading device, a socket portion 17 is attached to a predetermined position of the base member and fixed, and a guide plate provided with an opening in a portion where the contact glass is located is put on the socket portion 17 from above. To

[0014]

As is clear from the above embodiments, according to the present invention, the Xe lamp can be brought as close as possible to the contact glass, and the Xe lamp and the contact glass are affected by the tolerance of other members. Since it is accurately positioned at regular intervals without receiving light, there is an effect that uniform illuminance can be given to the document surface passing over the contact glass.

[Brief description of the drawings]

FIG. 1 is a partial perspective view of a main part of an embodiment of the present invention.

FIG. 2 is a configuration diagram of a facsimile apparatus having a document reading device to which the present invention is applied;

FIG. 3 is an exploded perspective view illustrating a configuration of a conventional reading unit.

[Explanation of symbols]

6 ... contact glass, 16 ... Xe lamp, 17 ...
Socket part.

Claims (1)

(57) [Scope of request for utility model registration] 1. A document reading apparatus comprising: a light source for illuminating a document passing over a contact glass; means for guiding reflected light from the document to form an image; and a reading sensor for photoelectrically converting the formed light image. A document reading apparatus, wherein the contact glass is held integrally with a light source in a socket portion of the light source.