JPH0545698U - Original cover - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide an original pressing cover that does not create a gap between the original and the mat, can press the original securely, and does not deteriorate the image quality. [Structure] When the document pressing cover main body 1 is warped due to a temperature rise, a shape memory member 3 is applied to the document pressing cover main body 1 to apply a force for preventing the warp to the document pressing cover body 1 by the deformation due to the temperature increase. It is installed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a document holding cover used in an image forming apparatus, a document reading device, or the like.

[0002]

[Prior Art]

 Conventionally, as shown in FIG. 6, for example, a main body 10 of a copying machine is provided with a contact glass 12 on which an original 9 is placed. Further, in order to hold the original 9 placed on the contact glass 12 during copying, the original pressing cover main body 1 whose surface on the contact glass 12 side is formed into a flat surface is made of resin or the like. 11 is openably and closably connected. On the surface of the document holding cover main body 1 on the contact glass 12 side, a mat 2 formed of an elastic flat plate member such as urethane is attached so as to be stuck. The document pressing cover body 1 and the mat 2 constitute a document pressing cover.

When the document holding cover is closed to hold the document 9 placed on the contact glass 12, the surface of the mat 2 is covered by the flatness of the document holding cover body 1 and the elasticity of the mat 2. The original 9 can be securely pressed in close contact with the surfaces of the contact glass 9 and the contact glass 12.

[0004]

[Problems to be solved by the device]

 However, in the document pressing cover having the above-described configuration, since the document pressing cover main body 1 is made of resin, it is deformed by molding conditions or heat generated inside the copying machine main body 10 due to continuous use of the copying machine. Then, as shown in FIG. 7, since the supporting portion 11 side of the document holding cover body 1 is fixed, the opposite side of the document holding cover body 1 is lifted from the contact glass 12, and the mat 2 attached to the document holding cover body 1 is also The mat 2 is deformed and rises to the extent that it cannot be absorbed only by the elasticity of the mat 2 (the size of the deformation is exaggerated in the drawing). Therefore, there is a problem that a gap is created between the original 9 on the raised side and the mat 2, the original 9 cannot be reliably pressed, and the image quality is degraded.

The present invention, in consideration of such problems of the conventional document pressing cover, provides a document pressing cover capable of reliably pressing the document without forming a gap between the document and the mat and not deteriorating the image quality. The purpose is to do.

[0006]

[Means for Solving the Problems]

 According to the present invention, in a document pressing cover including a document pressing cover body, when the document pressing cover body warps due to a temperature rise, a force that prevents the warp is applied to the document pressing cover body by the deformation due to the temperature rise. The shape memory member to be added is the document pressing cover attached to the document pressing cover body.

[0007]

[Action]

 According to the present invention, the shape memory member attached to the document holding cover main body is provided with a force for preventing the warp due to the temperature rise of the document holding cover body due to the deformation due to the temperature rise, in addition to the document holding cover body. Minimize the warpage of the cover body.

[0008]

【Example】

 The present invention will be described below with reference to the drawings showing an embodiment thereof.

FIG. 1 is a perspective view of an original pressing cover according to an embodiment of the present invention. That is, the original pressing cover for pressing the original connected to the upper part of the copying machine main body is formed of elastic urethane or the like on the surface of the resin original pressing cover main body 1 on the contact glass side on which the original is placed. The mat 2 is attached, and on the opposite surface thereof, a pocket-shaped holder 4 is formed, and an end of a rectangular flat plate-shaped shape memory member 3 made of, for example, a shape memory alloy is inserted into the holder 4. The central part of the cover is attached so that the central part thereof is projected upward (therefore, the central part thereof is away from the surface of the document pressing cover body 1) due to the temperature rise. The side of the document pressing cover body 1 where the step is raised (upper side in the drawing) is the side connected to the copying machine body.

The other end of the shape memory member 3 is fixed by a metal stopper 5, and the stopper 5 is fixed to the document pressing cover body 1 by a screw 51. FIG. 2 is a sectional view taken along the line A-A. As shown in the figure, the mat 2, the document holding cover body 1, and the shape memory member 3 are arranged in order from the contact glass side (upper and lower sides of the drawing). It has a three-layer structure.

Next, the operation of the above embodiment will be described.

First, since the temperature rise of the contact glass due to the generated heat of the copying machine body is small or not used for a while after the copying machine is used, the deformation of the document holding cover body 1 due to the heat is not yet generated. The original pressing cover main body 1 is small, as shown in FIG. 2, and therefore the surface of the mat 2 is also flat. When the document pressing cover is closed here, the document on the contact glass can be reliably pressed by the surface of the mat 2 (see FIG. 6).

After that, when the copying machine is used for a certain period of time, the heat generated from the copying machine body, for example, generated by the exposure lamp or the heater of the fixing device rises to the upper side of the copying machine and the contact glass The temperature of the mat 2 and the document holding cover body 1 is further raised.

Then, heat is transferred from the lower side to the upper side, so that the temperature of the original document pressing cover body 1 made of resin is larger in the lower side than in the upper side, and as a result, the lower side of the original document pressing cover main body 1 is Since it extends more than the upper side, as shown in FIG. 3A, in the case of only the document holding cover main body 1, its end portion is curved in the direction of arrow B. That is, the central part is deformed so as to be convex with respect to the contact glass. In this case, the mat 2 provided on the lower surface of the document pressing cover body 1 is also deformed in the same manner.

On the other hand, as shown in FIG. 3B, the shape memory member 3 itself bends in the direction of arrow C due to its temperature rise (attached in such a direction as described above). ing). That is, the document pressing cover body 1 is curved in a direction opposite to the curved direction.

Therefore, if the document holding cover in which both ends of the shape memory member 3 are fixed to the document holding cover body 1 is used as described above, the deformation of the document holding cover body 1 is deformed by the shape memory member 3. It is possible to hold down the amount of deformation of the document pressing cover main body 1 that is obstructed by the force, keep the flatness of the mat 2 and press the document securely.

In the above embodiment, the shape memory alloy is used for the shape memory member 3, but the shape memory member 3 is not limited to this, and when attached to the document pressing cover body 1, the document pressing cover body 1 warps due to a temperature rise. Any member can be used as long as it can be curved in the opposite direction, and for example, shape memory plastic or the like may be used.

Further, in the above-mentioned embodiment, the shape memory member 3 is attached to the upper side surface of the document pressing cover body 1, but the invention is not limited to this, and it may be a portion that prevents the document pressing cover body 1 from warping. For example, as shown in FIG. 4, it may be attached between the document pressing cover body 1 and the mat 2. Alternatively, as shown in FIG. 5, it may be formed by being embedded in the document pressing cover body 1.

Further, in the above-described embodiment, the shape of the shape memory member 3 is a quadrangular flat plate shape, but the shape is not limited to this, and a force sufficient to prevent the warp of the document pressing cover body 1 is applied to the document pressing cover body. Any shape that can be added to 1 may be used.

Further, in the above-described embodiment, an example in which the invention is applied to a copying machine which is an image forming apparatus is shown, but the invention is not limited to this, and may be applied to, for example, a document pressing cover used in an image reading apparatus.

[0021]

[Effect of the device]

 As is clear from the above description, according to the present invention, when the document holding cover body warps due to the temperature rise, a force that prevents the warping is applied to the document holding cover body by the deformation due to the temperature rise. Since the shape memory member is attached to the main body of the document pressing cover, there is no gap between the document and the mat, so that the document can be securely pressed and the image quality is not deteriorated.

[Brief description of drawings]

FIG. 1 is a perspective view of an original pressing cover according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1 of the same embodiment.

FIG. 3A is a sectional view of a document pressing cover main body for explaining the operation of the embodiment, and FIG. 3B is a sectional view of a shape memory member.

FIG. 4 is a sectional view of another embodiment.

FIG. 5 is a cross-sectional view of another embodiment.

FIG. 6 is a side view of a conventional document pressing cover.

FIG. 7 is a side view when a conventional document pressing cover body is deformed by heat.

[Explanation of symbols]

 1 Original pressing cover main body 2 Mat 3 Shape memory member

Claims (2)

[Scope of utility model registration request] 1. In an original pressing cover having an original pressing cover body, when the original pressing cover body warps due to a temperature rise, a force for preventing the warping is deformed by the temperature rise, and the original pressing cover body is deformed. An original pressing cover, wherein a shape memory member added to the above is attached to the original pressing cover main body. 2. The document pressing cover according to claim 1, wherein the shape memory member is a member that deforms in a direction opposite to a warp direction of the document pressing cover body.