JPH053525A - Document scanning device - Google Patents

Abstract

PURPOSE:To improve the wearing resistance of a sliding member by providing a plane faced to a travel guide at the sliding member and making it freely turnable around a shaft provided on a pedestal. CONSTITUTION:A light source 1 and a mirror 2 or the like are mounted on a pedestal 3, two thrust bearings 11 are pressurized and fixed near one edge of the pedestal, and they are the sliding members in the case of reciprocatively moving a traveling optical system on a shaft 10 held and fixed at an image exposing device. A pedestal round axis part 3' is formed near the other edge of the pedestal 3, on the other side, and a sliding member 13 is held freely turnably around the round axis part 3' and slid in the case of reciprocatively moving the traveling optical system on a plate rail 12. The sliding member 13 is composed of a hole part faced to the round axis part 3' and a plane part in contact with the plate rail 12. Therefore, since the round axis part 3' is provided on one point contact part side of the pedestal 3 and the round axis part 3' is equipped with the sliding member 13 held freely turnably around the round axis and in contact with the plate rail 12 with the plane faced to the plate rail 12, the wearing resistance of a manually operating member is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention illuminates a document placed on a document table such as glass with a light source, and causes the reflected image light to be reflected by a mirror to form an image on a line image sensor or a photoconductor. Further, the present invention relates to a document scanning device for scanning the traveling optical system including a light source, a mirror and the like to scan the document.

[0002]

2. Description of the Related Art Conventionally, as an image exposure device for inputting image information, a device for inputting the upper part of an image, such as a copying machine, an OCR (optical character recognition device) or a computer input device, has been known. It has a schematic configuration as shown in. In the figure, 101 is a light source, 102 is a mirror, 1
Reference numeral 03 is a base, and V ₁ is a light source unit composed of these. V ₂ is the two mirrors 104 and 105,
It is a mirror unit including a base 106 and the like. (Hereinafter, V ₁ and V ₂ are collectively referred to as a traveling optical system.) Original 10
7 is irradiated by a light source 101, and reflected image light thereof is reflected by mirrors 102, 104 and 105 and imaged by a focusing lens 108 on a line image sensor 109 which is a light receiving member. In the above optical path, the light source unit V ₁ and the mirror unit V ₂ are moved and scanned in the direction of the arrow at a speed ratio of 1: 1/2 based on the principle of the moving pulley to keep the optical path length from the original to the line image sensor constant. Since it is dripping, the original can be read uniformly.

By the way, the movement scanning of the light source unit V ₁ and the mirror unit V ₂ is usually performed along a traveling guide provided near both longitudinal ends of the bases 103 and 106. Indirect contact is made via another member at a total of three points, one at two points and the other at one point. Figure 7
Is a detailed view of the light source unit base, but the most common is the shaft 110 on the two-point side and two thrust bearings 111 fixed to the base, and the plate-shaped member on the one-side as shown in the figure. (Hereinafter, referred to as a plate rail.) 112 and a sliding member 113 that slides on the plate rail.

In the conventional example shown in FIG. 7, the base is supported at three points by thrust bearings and sliding members, and the base itself needs to have rigidity. In recent years, however, resin materials have been used with the progress of resin materials. I came to see the base. The present applicant has proposed a structure of a base using a flexible material such as a resin material in Japanese Patent Laid-Open No. 63-313959. The proposed light source unit will be described with reference to FIG.

In the figure, in order to keep the mounting position accuracy of the mirror 123 constant against deformation such as twisting of the base 122 using a flexible material such as a resin material, a straight surface 124 and an arc are formed. A mirror is attached to the surface 125 formed in a shape, a shaft 126 centering on the arc center 0 of the arc-shaped mounting surface 125 is provided from the base, and this shaft is placed on the traveling guide. With this configuration, the mirror 123 can maintain the flat state by absorbing the torsional displacement of the base on the arcuate mounting surface. Here, a resin containing glass is often used for the base 122 in order to secure the rigidity. Therefore, the shaft 12 is conventionally used for the reason of abrasion of the sliding surface and reduction of the friction coefficient.
A hollow shaft-shaped resin member was provided around 6.

[0006]

However, in the above-mentioned conventional structure, the hollow shaft-shaped member is in linear contact with the plate rail and is generally made of a resin material having a low coefficient of friction. There is no problem when the surface is smooth, but when the surface roughness of the plate rail is rough, the sliding portion of the hollow shaft member with the plate rail may be worn. When this wear occurs, there is a problem in that the height of the traveling optical system changes in the longitudinal direction and the positional accuracy of the image to be read deteriorates.

[0007]

In view of the above-mentioned conventional problems, the present invention provides a structure in which a sliding member is provided with a flat surface facing a running guide and is rotatably held with respect to a base. By doing so, the wear resistance of the sliding member is improved without cost up.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment FIGS. 1 to 3 show a first embodiment of the present invention, FIG. 1 is a perspective view of a light source unit, and FIG. 2 is a side view of a light source unit.
FIG. 3 is a front view of the light source unit. In the present embodiment, the document scanning device has substantially the same configuration as the conventional example, and different parts will be described in detail below.

In FIG. 1, 1 is a light source, 2 is a mirror, 3 is a base, 10 is a shaft, 11 is a thrust bearing, 1
Reference numeral 2 is a plate rail, and 13 is a sliding member. A light source 1, a mirror 2 and the like are mounted on a base 3, and a traveling optical system reciprocates on a shaft 10 which is press-fitted and fixed to two thrust bearings 11 near one end of the base and held and fixed in an image exposure device. It is a sliding member when moving. On the other hand, a base round shaft portion 3'is formed near the other end of the base, and the sliding member 13 is rotatably held around the round shaft portion 3'and the traveling optical system reciprocates on the plate rail 12. Sliding when exercising. Sliding member 13
Is composed of a hole portion facing the round shaft portion 3'and a flat portion in contact with the plate rail. (A retaining member for a sliding member (not shown) is provided on the round shaft portion.) That is, two points are provided between the thrust bearing and the shaft shaft, and one point is provided between the sliding member and the plate rail. Are in contact.

As a result, as shown in FIG. 2, even if the base 3 changes as indicated by the chain double-dashed line, the sliding member 13 comes into surface contact with the plate rail 12, so that wear of the sliding member is reduced. The flexible structure of the base can be utilized as in the conventional case. This configuration is the same for the mirror unit,
The description is omitted.

Therefore, according to this embodiment, a round shaft portion is provided on the one-point contact side of the traveling optical system base, and the round shaft portion is rotatably held around the round shaft and faces the plate rail. The wear resistance of the manual member is improved by providing the sliding member whose surface is flat and is in surface contact with the plate rail. Further, for example, even when the shaft 10 'is used instead of the plate rail as shown in FIG. 3, the contact between the sliding member and the shaft is a line contact, which is larger than the point contact of the conventional hollow shaft-shaped sliding member. Increases and wear resistance improves.

Second Embodiment FIGS. 4 and 5 show a second embodiment of the present invention. FIG. 4 is a side view of the traveling optical system, and FIG. 5 is a detailed view of the traveling optical system base. In the present embodiment, only the shape of the sliding member and the shape of the portion of the base that holds the sliding member are different from the first embodiment, and the same members will be denoted by the same reference numerals. To do.

FIG. 4 shows a light source unit U ₁ in the traveling optical system.
1 is a side view of the light source, 1 is a light source, 2 is a mirror, 3 is a base, and 1
2 is a plate rail, and 23 is a sliding member. A sliding member 23 is rotatably held around the round shaft 3'on the round shaft 3'formed on the base and slides on the plate rail 12 when the traveling optical system reciprocates. (Even in this embodiment, a retaining member for a sliding member (not shown) is provided on the round shaft portion.) The sliding member 23 has substantially the same curvature as the round shaft contacting the round shaft portion 3 '. There is a flat part that comes into contact with the plate rail and the plate rail, and is roughly U-shaped as shown in the figure.

As a result, as in the first embodiment, the base is 2
Even if the sliding member 23 and the plate rail 12 are in surface contact with each other even if they are changed as indicated by the dotted line, wear of the sliding member can be reduced. Since the structure of this embodiment is the same as that of the mirror unit, its explanation is omitted.

Further, since the sliding member is substantially U-shaped, the sliding member does not necessarily have to be held by the round shaft. For example, as shown in FIG. It is also possible to form a straight line on the upper side up to the light source of the base and the mounting portion 53 of the mirror, leaving the arc-shaped portion in contact with the sliding member from the round shaft. As a result, when the round shaft portion of the base is molded by the slide mold, the slide mold becomes unnecessary. Further, in the case where the molds are joined and separated in the vertical direction in FIG. 5 and the mold escapes are provided in the placing portion 53, the mold escapes can be eliminated, so that the mold structure of the base can be simplified. That is, if the portion in contact with the sliding member has an arc shape so that the sliding member can rotate, the other portions can have free shapes. Therefore, it is possible to realize the downsizing and the improvement of the rigidity of the base together with the simplification of the mold structure of the base.

Therefore, according to the present embodiment, the sliding member that slides on the plate rail is formed into a flat surface on the surface facing the plate rail, and is brought into surface contact with the plate rail to form a substantially U-shape. Not only the wear resistance of the moving member is improved, but also the mold structure of the base can be simplified.

[0017]

As described above, according to the present invention, the sliding member is provided with the flat surface facing the running guide and is rotatably held with respect to the base. It is possible to obtain an image exposure device having improved abrasion resistance.

Further, by making the sliding member substantially U-shaped, in addition to the above effects, it is possible to simplify the mold structure of the base of the traveling optical system, downsize the base, and improve the rigidity. is there.

[Brief description of drawings]

FIG. 1 is a perspective view of a light source unit according to a first embodiment of the present invention.

FIG. 2 is a side view of the light source unit according to the first embodiment of the present invention.

FIG. 3 is a front view of the light source unit according to the first embodiment of the present invention.

FIG. 4 is a side view of a light source unit according to a second embodiment of the present invention.

FIG. 5 is a detailed view of a light source unit according to a second embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a conventional image exposure apparatus.

FIG. 7 is a detailed view of a conventional light source unit base.

FIG. 8 is a detailed view of another conventional light source unit base.

[Explanation of symbols]

1 light source 2 mirror 3 bases 12 plate rails 13 Sliding member

Claims (2)

[Claims] 1. A light source for illuminating a document placed on a document table, a mirror for guiding image light from the document to a light receiving member, a traveling optical system having a base on which the above members are mounted, and a traveling system. A traveling guide member disposed in the apparatus near both ends in the longitudinal direction of the optical system and substantially parallel to the optical axis of the traveling optical system, and a sliding member that slides on the traveling guide attached to the base. In a document scanning device that scans a document by moving and scanning, the sliding member has a flat surface facing a running guide, and is rotatably held with respect to a shaft provided on the base. Document scanning device. 2. The document scanning device according to claim 1, wherein the sliding member has a substantially U shape.