JPS5948748A - Original pressing plate - Google Patents

Abstract

PURPOSE:To press and support an original tightly by using a relatively lightweight pressing plate, by arranging high specific gravity parts and low specific gravity parts dispersedly over the entire surface, and forming an original pressing surface flatly. CONSTITUTION:The original pressing plate for pressing and holding an original placed on the platen of a picture forming device has a top flat plate part and the numbers of high specific gravity members 2 projecting downward in parallel. Those high specific gravity members 2 are made of metal, hard resin, etc., and recessed parts between the parallel downward projecting parts are charged with low specific gravity members 3 formed of elastic materials made of foamy bodies such as foamed polyurethane, etc.; and a white member 4 is attached to its under surface in one body and the pressing plate abuts on the exposure glass plate 5 of a copying machine uniformly on the whole. Pressing operation depends mainly upon the high specific gravity members 2, so the original is pressed tightly even if the pressure plate itself is relatively light in weight, so preventing a shift of the original as much as possible.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Object of the Invention The present invention relates to a document mounting die for an image forming apparatus such as a copying machine or a printing machine, and particularly to a document pressure bonding plate thereof.

In the above-mentioned image forming apparatus, especially when processing notebook-shaped originals, if the original document itself is light and the document pressure plate that presses and holds the document in a fixed position is lightweight, the document on the pressure bonding plate will be The document may be misaligned due to insufficient holding force. This problem often occurs, especially in copying machines where the document mounting mill moves, and the position of the image relative to the transfer paper changes as a large number of copies are made continuously.
From time to time, we experience not being able to obtain copies of new images.

In order to avoid such inconveniences, it is immediately conceivable to increase the M amount of the original pressure bonding plate, but this will impair the operability of the pressure bonding plate and should not be used if the document mounting table is still moved. There are disadvantages such as having to drive heavy objects.

A method has also been proposed in which a large number of small concave and convex portions are formed on the document pressing surface of a folded document pressure bonding plate, and the convex portions locally press the document so that the pressing effect per unit area is uniform for everyone. This ridge means is not suitable if the original is smaller than the transfer paper, or if the original is transparent, since shadows from the convex portions will appear.

The present invention has been made in view of the above-mentioned drawbacks of the known manuscript pressure bonding plates. At the same time, the area in contact with the original is formed into a uniform flat surface, and if necessary, a thin white layer is formed at the core to suppress the weight of the pressure bonding plate and to hold the original. It is an object of the present invention to provide a document pressure bonding plate that has a large effect and does not cause document displacement.

(B) Structure of the Invention Embodiments of the present invention will be explained with reference to the accompanying drawings. FIG. 1 is a perspective view showing the case where the present invention is applied to a copying machine.
3, and an original pressing plate 1 whose opposing edges 1111I open and close in the direction of arrow A is attached.

FIG. 2 is an enlarged view schematically showing the document pressure bonding plate 1 shown in FIG. 1 as viewed from the direction of arrow X in the figure. The pressure bonding plate 1 is provided with a high specific gravity member 2 consisting of a flat top portion and a number of portions falling downward in parallel from the top flat portion. Third
The figure shows a partially oblique view of the high specific gravity member viewed diagonally from below. This high specific gravity member shall be constructed of metal, hard synthetic resin, etc., and shall have a concave r between the falling parts arranged in parallel.
Jr is filled with a low specific gravity member 3 made of an elastic material made of foam such as polyurethane foam, polystyrene, polyethylene, vinyl chloride, nitrile rubber, etc., and a white member 4 is integrated on the lower surface of the member. The pressure bonding plate is attached uniformly to the exposure glass plate 5 of the copying machine as a whole.

Since the document pressure bonding plate according to the present invention has the above-mentioned configuration, it is possible to use a high-specific gravity material, especially for a sheet-like document placed on the glass plate 5, which is the original placement surface. Since the pressure bonding plate 2 has a pressing action, the pressure plate itself is relatively small in weight and strongly presses the document even if it is moved, so that the displacement of the document during operation of the copying machine can be minimized.

Furthermore, since the lower surface of the pressure bonding plate is formed flat as a whole and is made of a white material, it is possible to prevent shadows from appearing on the transfer paper due to the difference in size between the original and the transfer paper.

FIGS. 4 to 6 show other configurations of the document pressure bonding plate according to the present invention, and each of them shows the configuration of the high specific gravity member like FIG. 3.

In the case shown in FIG. 4, the high specific gravity members 2 are arranged in parallel in the same way as in the case shown in FIG. It is getting bigger according to With this configuration, an extremely large force is applied to the document at the high specific gravity member portion, and a greater force and support effect can be obtained.

The high specific gravity member shown in FIG. 5 is formed in a cylindrical shape projecting downward, and in FIG. 6, the high specific gravity member is formed in a tapered truncated conical shape.

These items are similar to those shown up to Figure 4,
It is easy to understand that this has a great effect of suppressing manuscripts.

In addition, in the case shown in FIGS. 4 to 6, the gap between the high specific gravity members (or the low ratio M member similar to that shown in FIG. Of course it's a thing
It is lliii.

(C) Purpose of the Invention As described above, the document pressure bonding plate according to the present invention is arranged such that the high specific gravity member and the low specific gravity member are dispersed and mixed over the entire surface of the notebook-like document (2 (distributed) so as to apply ψ pressure. Overall, the relatively lightweight crimp plate can be used to firmly press and support the original, making it easy to operate, and even in equipment where the original table is moved, it does not increase the criminal force. It is possible to effectively prevent document misalignment with a simple configuration.

Since the document contacting surface of the crimping plate is flat and coated with white material, unsightly shadows will not be produced on the recording material due to the difference in size between the document and the recording material.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the case where the present invention is applied to a copying machine, Fig. 2 is a side view showing the structure of the original pressure bonding plate according to the invention, and Fig. 3 is a view showing only the high specific gravity paulownia part. FIGS. 4 to 6 are perspective views of -gB, which do not show other embodiments of the present invention and show the structure of the raised part. DESCRIPTION OF SYMBOLS 1... Original pressure bonding plate, 2... High specific gravity member, 3... Low specific gravity member, 4... White member, 5... Transparent glass plate.

Claims (1)

[Claims] In order to suppress and hold the original placed on the original placing table of an image forming apparatus, a document pressure bonding method has high specific gravity parts and low specific gravity parts distributed over the entire surface, and the original pressing surface is formed in a flat shape. Board.