JPH02110445A - Original placing plate - Google Patents

Abstract

PURPOSE:To hold glass G under a state in which the glass G has the minimum deflection by holding the glass of the title large original placing plate with a structural member having either upward bending or a rib and subsidiarily supporting the lateral direction of the glass. CONSTITUTION:While the lower surface of the glass G is held by bending one part of a front side plate 1 to hold the glass G upward, the strength of the glass G is heightened by providing a part 1b parallel to the direction of the thickness of the glass, namely, orthogonal to the holding part. For the back side of the original placing plate, the glass G is held by laying a channel 10 between a left side plate 9 and a right side plate the shape of the channel is made into a shape having a part 10a higher than the lower surface of the glass, and the strength of the glass is heightened by giving a height directional beam 10b to the back side. It can be prevented that the original placing plate is bent because of the weight of the glass G and an out-of-focus picture is obtained by providing the bending of one part of the holding members 1 and 10 for the glass G in the direction of the thickness of the glass and heightening the strength in the above-mentioned manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an original AM table used in an original reading device such as a copying machine.

[Conventional technique ml] Conventionally, in a document reading device, a document glass G is placed on the front plate L and rear plate 2, which are structural members, as shown in FIG. System 4, lens L
, the CCD reads the original 0. The original O is pressed against the glass G using a white board sheet 7, a sponge 6, and a rubber plate 5 so as not to float.

[Problem B that the invention seeks to solve] In conventional A3-sized reading devices that have been put into practical use, a thin glass of about 3''' is used because the strength of the glass G is not required to be very strong. Therefore, since it was light, the part that held the glass did not need to be strong.

However, in a device that reads large manuscripts such as A1 size, when a thick book is placed on the glass, or when the center of a double-page book is held down so that it does not float, the glass should be 518 to 8" in order to reduce the amount of deflection. It is necessary to use glass with a thickness of about 8 mm. In this case, with the conventional holding method as shown in FIG. 2, the cantilever of the back plate 2, into which the illumination part 4 of the optical system and the scanning table 3 are inserted, becomes long and bends due to the weight of the glass G. As a result, the distance between the glass G and the lens L becomes narrow, resulting in an out-of-focus image.In particular, the lighting system 4 is placed close to the glass in order to obtain a sufficient amount of light, and may collide with the glass or the overhang of the back panel. .

[Means for Solving the Problems (and Effects)] In order to solve the above-mentioned drawbacks of the conventional glass, in the present invention, a part of the glass holding member is bent in the thickness direction of the glass to increase its strength. .

[Example] In FIG. 1, a part of the front plate l holding the glass G is bent upward to hold the lower surface of the glass G and a part 1b parallel to the thickness direction of the glass, that is, perpendicular to the holding part.
The strength has been increased. On the back side, the channel lO is passed between the left side plate 9 and the right side plate (not shown) to hold the glass, and the channel is shaped to have a portion 10a higher than the lower surface of the glass, and has a beam lOb in the height direction to increase strength. There is.

In addition, with this channel shape, in the case of a large original O that protrudes from the glass G, when pressed with the original pressure plate 5°6.7, the upper surface la of the front plate is almost the same surface as the glass G, so the original It won't break, but the back side will bend almost at a right angle, damaging the original. Therefore, the third
In the example shown in the figure, the rear plate holding the rear glass from near the top surface of the glass G is bent diagonally 2b so that it becomes higher as it moves away from the glass, which prevents the original from bending and also reduces the strength by 1. The configuration is such that this is not allowed.

In the example shown in FIG. 3, the front plate does not protrude much, so there is little bending, so upward bending is not required. or,
Although the back side has been explained using the back side plate 2, it may be a separate structural member as shown in FIG.

Also, if the document pressure plate is made relatively small enough, it is thought that bending of the document can be prevented, but if the maximum document size to be placed is fixed, the glass will have to be made larger, which will reduce the holding strength and increase the size of the machine. This will lead to

Although the above explanation has been about the deflection of the glass holding member, a holding method for reducing the deflection of the glass will be described.

FIG. 4 is a perspective plan view of the original Jim table according to the present invention. The glass is held with sufficient strength in the longitudinal direction by the front plate 1 and the rear plate 2, but this allows the glass to easily bend downward as shown by the dotted chain line in Figure 2. Since it is necessary to maintain a flat state with the lens L with a predetermined precision, in the document mounting table according to the present invention, only the center portions 8a and 9b of the right side plate and the left side plate are placed.

To help hold the glass, the glass G is held in the lateral direction with lower strength than in the longitudinal direction. This is to prevent this phenomenon, since if it is held with strength in the transverse direction, it is necessary to achieve precision on the four sides, and it is difficult to achieve the same horizontal flatness on the four sides, resulting in wobbling.

Also, when inspecting the inside of the machine or cleaning the glass G,
Notches 8b and 9b for inserting hands may be provided to facilitate removal, as long as deflection of the glass G in the lateral direction can be prevented by elastically holding it.

The left and right side plates may be made of spring material, but since they have little deflection, even iron plates used for general structures can be used in an elastic range that does not cause permanent deformation, so there is no need to use any special material.

Fig. 5 is a perspective view for better understanding the structure of Fig. 4, and shows the state in which the rubber plate 5, etc. that constitutes the document pressure plate is open, and is placed over the glass G in actual use. .

Further, in a large-format reading device, the glass G is large and heavy, or it is necessary to remove the glass to inspect the inside of the machine or clean the glass. In the reading device according to the present invention, a slider 11 made of polyethylene or the like is embedded in the back side plate 2 by taking advantage of the fact that the back side plate is higher than the lower surface of the glass, the glass is slid onto this part, and the slider 11 is moved backward as shown in FIG. , the inside of the machine can be inspected without lifting or removing the glass. Moreover, since the back plate in which the slider 11 is embedded is a strong structure, the glass will not slip off due to unstable vibrations or the like.

[Effects of the Invention] As detailed above, it is possible to bend the glass G by bending the glass of the stand upward or by holding it with a structural member having ribs and supporting it in the lateral direction. It can be maintained in a state with less

Furthermore, by making the shape of the structural member oblique as it moves away from the glass, it is possible to read large originals without creating creases.

Also, the heavy glass has to be moved aside to inspect the interior.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the original document mounting table according to the present invention, and FIG. 2 is the original v4J! of the conventional example. ! FIG. 3 is a sectional view of another embodiment of the document mounting table A according to the present invention. 4 is a plan view of the embodiment shown in FIG. 3, FIG. 5 is a perspective view of the embodiment shown in FIG. 3, and FIG. 6 is a sectional view of another embodiment. The front plate 2 is the rear plate lO, the channel 11 is the slider J, Figure 2, Figure 4.

Claims (1)

[Scope of Claims] 1. A document mounting table comprising a glass on which a document is placed and a glass holding means configured such that the upper surface of the structural member that holds the glass is higher than the lower surface of the glass. 2. The document mounting table according to claim 1, wherein the glass holding means has an inclined surface that becomes higher in the direction away from the glass, and is higher than the upper surface of the glass. 3. The document mounting table according to claim 2, further comprising a document pressure plate for pressing the document from above in the vicinity of the structural member having an inclined surface. 4. A document mounting stand characterized by a fixed glass on which a document is placed, and a longitudinal direction of the glass held on a strong structural member, and a transverse direction held on a flexible structural member. 5. The document mounting table according to claim 4, wherein the surface of the holding member in the lateral direction that contacts the glass is a region near the center. 6. The document mounting table according to claim 1, wherein a projection (for sliding the glass) is provided on the upper surface of the structural member.