JP2003066545A - Document pressure plate, image reading device, and image forming device - Google Patents

Abstract

(57) Abstract: A document pressure plate, an image reading device, and an image forming device for uniformly pressing a contact portion of a contact glass and a document pressure plate and reducing stress on an adhesive surface between the press portion and a frame portion during an opening operation. Provide equipment. A sheet member (18) in contact with a document placed on a contact glass, an elastic member (11) disposed between the sheet member (18) and a frame portion (8), and an elastic member (11) A plurality of flexible films 17 which are arranged between the frame portion 8 and extend in a direction perpendicular to the opening / closing direction (or A direction) of the frame portion 8; Removable tapes (surface fasteners) 12 and 19 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document pressure plate mounted on a copying machine, a facsimile machine, an image scanner, etc., an image reading apparatus and an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, a document pressure plate of this type has a frame portion for covering a contact glass surface, a hinge portion for connecting the frame portion and the main body of the image reading apparatus in an openable and closable manner, and an adhesive tape or the like for the frame portion. An elastic member (such as a sponge) fixed by the pressure member, and a pressing portion (including a white sheet) attached to the pressing surface side of the elastic member (the side facing the contact glass at the upper part of the main body of the image reading apparatus), When the hinge part was attached, the pressing part was adjusted so as to be in close contact with the contact glass.

As described above, since the pressing portion for pressing the original surface on the contact glass is fixedly joined to the frame portion and the elastic member with an adhesive tape or the like, even if the hinge portion is attached to the main body of the apparatus, the position may be a little. If it is misaligned, the entire surface of the pressing part will not come into close contact with the contact glass, and the document position reference member (hereinafter called the scale) provided on the side surface of the contact glass.
Will interfere with. As a result, the document position reference member is not sufficiently pressed at the edge of the read document, and the leading edge of the document rises from the contact glass in the created gap, so that the document at the edge cannot be accurately read and outside light is not emitted from the gap. enter,
That portion is printed in black, which is not desirable as a read image.

Therefore, in order to solve such a problem, a surface fastener (velcro tape (registered trademark)) is attached to an elastic member such as sponge and a frame portion so that the pressing surface does not ride on the scale and the contact glass It has been proposed that the elastic member and the pressing portion can be easily finely adjusted so that the entire surface of the pressing portion can be brought into close contact with the pressing member (JP-A-10-1538).
No. 89). Here, surface fasteners are attached to the four corners of the elastic member.

However, according to the conventional method,
If the contact glass and the entire pressing portion can be brought into close contact with each other without interfering with the scale, the following problems occur.

For example, considering the case of reading a small-sized original, the contact area between the pressing portion and the contact glass becomes large, and therefore the contact glass and the pressing portion have a high degree of contact due to static electricity generated during reading. As a result, when the document pressure plate is opened after reading the document, the pressing portion and the contact glass are in close contact with each other, and a force is required to open the document pressure plate. When force is applied to open the document pressure plate in this way, the document moves in close contact with the pressing portion while floating upward, so that if the document moves to the hinge side, it may be pinched by the document pressure plate and the main body and damaged. . Further, since the surface fastener is attached to the sponge portion, when such adhesion is generated, stress may be applied to the adhesive surface between the frame portion and the pressing portion, and the adhesive surface of the sponge portion may be damaged. Furthermore, the contact glass is placed on the mounting part of the main body and adhered with double-sided tape or the like, and the scale is pressed from the top so as to interfere with the side surface of the contact glass, and attached to the main body with screws. Therefore, if the degree of close contact between the original pressure plate and the contact glass is high, the contact glass on the operator side may be slightly lifted. In this case, dust may enter through the gap and
If the degree of uplift is large, a large impact may be applied to the contact glass.

In order to deal with such a problem, a structure has been proposed in which a step member is provided on the opposite side of the contact glass from the pressure plate rotating shaft to reduce the degree of contact between the contact glass and the pressure plate (actual fairness 07- No. 034425).
With this structure, a gap is formed between the pressing portion and the contact glass, so that the pressure plate can be easily opened.

Further, in this type of apparatus, the white sheet included in the pressing portion of the original pressure plate is formed of a conductor sheet having an uneven shape on the surface, and the book original of the book original caused by the charging of the pressing portion of the original pressure plate is formed. Some have prevented breakage or damage (Japanese Patent Laid-Open No. 7-128932).

In addition to the above-mentioned publications, those related to this type of apparatus include Japanese Utility Model Publication No. 4-22346, JP-A-6-313930, and JP-A-7-953.
No. 68, No. 7-191419, No. 8
-201935 is available.

[0010]

However, if the step member of the technique disclosed in Japanese Utility Model Publication No. 07-034425 is provided, the sheet cannot be completely adhered to the contact glass, and the original pressing force becomes uneven. A problem occurs. In addition, since light leaks through the gap between the contact glass and the pressure plate caused by the step, outside light enters through this gap, and this portion is printed in black, which is not desirable as a read image. Further, the above-mentioned JP-A-7
In the technique disclosed in Japanese Patent Laid-Open No. 128932, the conductor sheet is interposed between the carriage and the device frame and wound around the take-up roller, so that the device configuration becomes complicated and a special conductor is used. The processing of the sheet may increase costs.

The present invention has been made in order to solve such a problem. The contact glass and the pressing portion of the original pressure plate are brought into close contact with each other evenly, and the adhesive surface between the pressing portion and the frame portion is opened during the opening operation. An object of the present invention is to provide a document pressure plate, an image reading device, and an image forming device that reduce stress. Further, the present invention has been made to solve such a problem, and it is possible to easily open the original while reducing the impact of the contact glass during the opening operation while closely adhering the original. An object is to provide a pressure plate, an image reading device, and an image forming device.

[0012]

According to a first aspect of the present invention, there is provided a document pressure plate which is openably and closably connected to a main body of an image reading apparatus and which is divided vertically into an opening and closing direction, and the image. A pressing unit for pressing a document placed on the contact glass of the main body of the reading device and an attaching / detaching means for attaching / detaching the pressing unit to / from the frame unit are provided, and the pressing unit is divided into a plurality of parts. In addition, an elastic member is provided on which a sheet member that contacts the original placed on the contact glass is mounted. With this configuration, the divided elastic members follow the thickness and shape of the document pressed against the sheet member, and the document is evenly and closely attached to the contact glass.

According to a second aspect of the present invention, in the first aspect, the elastic member has a structure in which the elastic member is divided corresponding to the division position of the frame portion. With this configuration, the elastic member of the frame portion follows the bending of the divided frame portion due to the thickness and shape of the original, and makes the original evenly adhere to the contact glass.

According to a third aspect of the present invention, in the second aspect of the present invention, in the second aspect, the elastic member is divided vertically to the opening / closing direction of the frame portion. With this configuration, the bending of the frame portion divided as described above due to the thickness and shape of the original is also followed, and the original is brought into close contact with the contact glass evenly.

A document pressure plate according to a fourth aspect of the present invention is the document pressure plate according to the second aspect, wherein a length from a connecting end of the frame portion to a division position of the frame portion is from the division position of the frame portion to the frame portion. It has a configuration set to be shorter than the length to the open / close end. With this configuration,
Since the area of the first pressing portion mounted on the first frame portion on the connecting end side is smaller than the area of the second pressing portion mounted on the second frame portion on the opening / closing end side, for example, a scale The first pressing portion is pressed against the end of the book original positioned on the connecting end side to elastically deform, and then the second pressing portion uniformly presses the book original from above against the contact glass surface. It will be.

According to a fifth aspect of the present invention, in the original pressure plate according to the second aspect, the hardness of the elastic member provided from the connecting end of the frame portion to the division position of the frame portion is
It has a configuration that is set to be softer than the hardness of the elastic member provided from the divided position of the frame portion to the open / close end of the frame portion. With this configuration, for example, the soft first pressing portion is pressed and elastically deformed by the end portion on the connecting end side of the book original positioned by the scale, and then the hard second pressing portion raises the book original upward. Therefore, the surface of the contact glass is pressed evenly.

According to a sixth aspect of the present invention, there is provided a document pressure plate which is openably and closably connected to a main body of an image reading device and which is divided vertically into an opening and closing direction and a contact of the main body of the image reading device. A pressing portion for pressing the original placed on the glass and a plurality of attaching / detaching means for attaching / detaching the pressing portion to / from the frame portion are provided, and the pressing portion is placed on the contact glass. A plurality of flexible members disposed between the elastic member and the frame portion, and a plurality of flexible members disposed between the sheet member and the frame portion. Each of the flexible members has a configuration in which the plurality of attaching / detaching means are attached. With this configuration, in the document pressure plate, a flexible member (flexible film, flexible sheet, etc.) having a smaller elastic force in the direction perpendicular to the pressing surface than the elastic member on both sides of the elastic member of the pressing portion, and a sheet member. By respectively providing the flexible member and the frame portion so as to be detachable by a surface fastener or the like, the original on the contact glass can be uniformly and surely pressed by the sheet member. Further, by making the adhesion between the flexible member and the attachment / detachment means such as the surface fastener larger than the adhesion between the contact glass and the sheet member when opening the original pressure plate, the pressing portion contacts. The force pulled to the glass side is weakened, and the opening operation of the document pressure plate becomes easy. Further, since a plurality of the flexible members are arranged to extend in a direction perpendicular to the opening / closing direction of the document pressure plate, a plurality of flexible members are uniformly tensioned during the opening operation of the document pressure plate. It will be. Even if the contact force between the contact glass and the sheet member is increased by the opening operation of the document pressure plate as compared with the pressing force, the flexible member and the elastic member are not separated from each other.

According to a seventh aspect of the present invention, there is provided a document pressure plate according to the sixth aspect, wherein the flexible member is divided at division positions of the frame portion. With this configuration, the flexible member of the pressing portion can follow the deformation of the elastic member due to the thickness and shape of the document pressed against the sheet member.

According to an eighth aspect of the present invention, there is provided a document pressure plate according to the seventh aspect, wherein the flexible member is divided perpendicularly to an opening / closing direction of the frame portion. With this configuration, the flexible member of the pressing portion can follow the deformation of the elastic member due to the thickness and shape of the document pressed in contact with the sheet member, and the amount of use of the flexible member can be saved. .

According to a ninth aspect of the present invention, there is provided a document pressure plate which is openably and closably connected to a main body of an image reading device and which is divided perpendicularly to the opening and closing direction, and a contact of the main body of the image reading device. A pressing portion for pressing the original placed on the glass and a plurality of attaching / detaching means for attaching / detaching the pressing portion to / from the frame portion are provided, and the attaching / detaching means are provided at six locations excluding the four corners of the pressing portion. It has the configuration arranged as described above. With this configuration, as compared with the case where the attachment / detachment means is provided at the four corners of the pressing portion, air is easily introduced between the pressing portion and the contact glass from the end portion of the pressing portion to reduce the pressure during the opening operation of the document pressure plate. In addition, the adhesive force between the contact glass and the pressing portion can be appropriately reduced to facilitate the opening operation of the document pressure plate.

According to a tenth aspect of the present invention, in the document pressure plate according to the ninth aspect, the attaching / detaching means is arranged at a central portion excluding the four corners of the pressing portion. With this configuration, since air easily enters between the pressing portion and the contact glass as described above during the opening operation of the original pressing plate, the contact force between the contact glass and the pressing portion is appropriately reduced to reduce the original pressing plate's force. This will facilitate the opening operation.

According to an eleventh aspect of the present invention, in the document pressure plate according to the ninth or tenth aspect, the attaching / detaching means has the hook portion of the surface fastener adhered to the frame portion and the hook portion adhered to the pressing portion. A loop portion of a surface fastener is provided, and the area of the hook portion and the area of the loop portion are set to be different from each other. With this configuration, the adhesiveness and the ease of peeling are improved by changing the areas where the hook portion and the loop portion face each other. For example, it is possible to flexibly deal with variations in parts and to reliably position and attach the pressing portion. Furthermore, the cost required for maintenance can be reduced by reducing the area of the loop portion on the pressing portion side, which is frequently replaced for maintenance, compared to the hook portion on the frame portion side, for example.

A document pressure plate according to a twelfth aspect of the present invention is the document pressure plate according to the eleventh aspect, wherein the pressing portion includes a sheet member that comes into contact with a document placed on the contact glass, and the sheet member and the frame portion. A plurality of elastic members that are arranged between the elastic members and the frame portion and that are arranged between the elastic members and the frame portion; A plurality of flexible members that are vertically divided with respect to the opening / closing direction of the frame portion at a position, and the loop portion of the surface fastener is attached to each of the plurality of flexible members. ing. With this configuration, the loop portion of the surface fastener is attached to the flexible member having a smaller elastic force in the vertical direction with respect to the pressing surface than the elastic member as compared with the case where the loop portion of the surface fastener is directly bonded to the elastic member of the pressing portion. In this case, even if the contact force between the contact glass and the sheet member is increased by the opening operation of the document pressing plate as compared with the pressing force, the flexible member and the elastic member are not separated from each other.

A document pressure plate according to a thirteenth aspect of the present invention is the document pressure plate according to the twelfth aspect, wherein the area of the loop portion of the surface fastener is set to be smaller than the area of the flexible member, and The loop portion has a configuration arranged in the central portion of the flexible member except for the four corners.
With this configuration, the opening operation of the document pressure plate causes the sheet member to bend near the divided position of the frame portion, and the elastic member adhered to this sheet member is elastically deformed following this and adhered to this elastic member. When the flexible member is bent, the loop portion of the surface fastener is bonded to the central portion of the flexible member, so that the displacement of the loop portion due to the bending of the flexible member is suppressed, It becomes difficult for the loop portion to be peeled from the flexible member.

A document pressing plate according to a fourteenth aspect of the present invention is the elastic member according to any one of the eleventh to thirteenth aspects, wherein the hook portion of the surface fastener is mounted on the bottom surface of the frame portion facing the pressing portion. Is provided. With this configuration, the variations of the pressing portion, the frame portion, and the components of the surface fastener are adjusted, and the loop portion is reliably attached to the hook portion of the surface fastener.

According to a fifteenth aspect of the present invention, in the document pressure plate according to the fourteenth aspect, the height of the elastic member is such that the hook portion of the surface fastener projects from the end face of the rib provided on the frame portion. It has a set configuration.
With this configuration, since only the hook portion projects from the rib end surface of the frame portion, the hook portion is pressed against the loop portion adhered to the flexible member of the pressing portion with an appropriate contact pressure. Further, the height of the pressing portion can be made uniform by the flexible member of the pressing portion and the rib of the frame portion.

According to a sixteenth aspect of the present invention, in the original pressure plate according to any one of the first to fifteenth aspects, the sheet member has a structure in which a surface in contact with the contact glass is roughly processed. With this configuration, a gap is formed between the sheet member and the contact glass by a simple roughing process on the surface of the sheet member (including the white sheet), so that the contact force between the contact glass and the pressing portion is appropriately reduced. This facilitates the opening operation of the document pressure plate.

According to a seventeenth aspect of the present invention, in the sixteenth aspect of the present invention, in the sixteenth aspect, the surface roughness of the sheet member is different between the connecting end side and the opening / closing end side of the frame portion. With this configuration, the surface roughness of the sheet member (including the white sheet) is set so that the opening / closing end side of the frame portion becomes rougher than the opening / closing end side (rotating shaft side to be described later). It is possible to reduce the adhesion force of the document to facilitate the opening operation of the document pressure plate and prevent the incidence of external light.

An image reading apparatus according to the eighteenth aspect of the present invention has a structure provided with the document pressure plate according to any one of the first to seventeenth aspects. With this configuration, as described above, since the opening operation of the document pressing plate is easy and the quality reliability is high, it is possible to realize the image reading apparatus having excellent operability and high image quality.

An image forming apparatus according to a nineteenth aspect of the present invention has a structure provided with the document pressure plate according to any one of the first to seventeenth aspects. With this configuration, as described above, since the opening operation of the document pressure plate is easy and the quality reliability is high, it is possible to realize an image forming apparatus having excellent operability and high image quality.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] As shown in FIG. 1, an image reading apparatus according to a first embodiment of the present invention has a contact glass 20 (see FIG. (Shown in FIG. 2) a sheet member 1 in contact with a document 1 placed thereon
8, an elastic member 11 arranged between the sheet member 18 and the frame portion 8, and the elastic member 11 and the frame portion 8
A plurality of flexible films 17 arranged in a direction perpendicular to the A direction, and a surface fastener (velcro tape (registered trademark)) 12 for attaching and detaching the flexible films 17 and the frame portion 8, And 19 are provided. The hook-and-loop fastener has a loop portion 12 in which a pile surface is formed.
And a hook portion 19 in which a hook-shaped projection is formed,
A detachable tape that can be attached and detached.

In FIG. 2, light is emitted from the lamp 2 toward the original 1 placed on the contact glass 20, and the reflected light passes through the first mirror 3, the second mirror 4, and the third mirror 5. The light is focused by the lens 6 and the image of the original 1 on the contact glass 20 is formed on the CCD 7. Also,
When reading in the sub-scanning direction, the lamp 2 and the first
By moving the second mirror 4 and the third mirror 5 by "1/2" while the mirror 3 moves by "1" to the right side in FIG.
The scanning is performed while keeping the optical path length of the lens 6 constant. A document pressure plate (shown in FIG. 3) is provided on the contact glass 20 so as to be opened and closed by a connecting member such as a hinge.

In FIG. 3, a pressing portion 9 for pressing the original is detachably attached to the frame portion 8 of the original pressing plate. Further, the document pressure plate includes a frame portion 8
By the hinge part 10 that connects the main body of the image reading device with
It is mounted so that it can be opened and closed with respect to the contact glass surface (original surface) on the top of the main body. By opening the frame portion 8 with respect to the document surface, the document is placed on the contact glass,
Or you can remove it from the contact glass,
By closing the frame portion 8 with respect to the document surface, the document can be pressed against the contact glass surface. The frame portion 8 and the pressing portion 9 may be one component or may be formed by combining a plurality of components. Further, in the present embodiment, although the frame portion 8 and the pressing portion 9 are of the type that bends in the middle, they may be of the type that does not bend.

Further, as shown in FIG. 1, the pressing portion 9 is
A sheet member 18 for pressing a document, and this sheet member 18
The elastic member 11 has a smaller area by a predetermined amount, a plurality of flexible films 17, and loop portions 12 of the surface fastener provided at a plurality of positions on the flexible film 17. Here, the sheet member 18 is formed of polyethylene terephthalate (PET) resin or the like, and is a white member so that the periphery of the document is not printed black when reading the document. The elastic member 11 is made of a material having high elasticity such as sponge, and is attached to the sheet member 18 with a double-sided tape. Further, the elastic member 11 is provided not to have the same area as the sheet member 18 but to be slightly smaller. The flexible film 17 is made of a material (e.g., mylar) having a smaller elastic force than the elastic member 11 due to the force in the direction perpendicular to the pressing surface against the frame portion 8.
The sheet is not a single-sided sheet like the sheet member 18 or the sheet member 18, but is a film sheet divided perpendicularly to the opening / closing direction (A direction) of the frame portion 8, and each flexible film 17 has a predetermined shape. Elastic member 1 so as to be adjacent at intervals
It is affixed on top of 1 with double-sided tape.

Since the flexible film 17 has a predetermined elastic force, when one film sheet is attached to the entire surface of the elastic member 11 without being divided as in the present embodiment, the frame portion is not formed. When a force is applied in the direction of removing the elastic member 11 from 8 (indicated by the arrow in FIG. 5), a force is generated to return the one film sheet to the frame portion 8 side (the direction opposite to the arrow in FIG. 5). However, it cannot be easily removed. Further, if the adhesive force of the surface fastener (including the loop portion 12 and the hook portion 19) is larger than the elastic force of the one film sheet when the one film sheet is forcibly peeled off, the one sheet film is removed. Since the film sheet of No. 2 is bent, the one film sheet is formed in a "V" shape, and it becomes impossible to uniformly press the entire document surface on the contact glass.

On the other hand, as in this embodiment, by dividing the flexible film 17 perpendicularly to the direction A, a plurality of loop portions 12 of the surface fastener arranged in each divided piece.
Can be sequentially and reliably removed from the frame open end side opposite to the hinge side. Further, the plurality of loop portions 12 are attached on the flexible film 17 so as to be aligned with the positions of the plurality of hook portions 19 attached to the frame portion 8. Here, the area of the hook portion 19 on the side of the frame portion 8 may be the same as that of the loop portion 12 on the side of the pressing portion 9 or may be different from the position of the loop portion 12 due to an attachment error of (velcro tape (registered trademark)). The area of either the hook portion 19 or the loop portion 12 may be increased in consideration of the case where they do not match. Further, the hook portion 19 may be provided on the flexible film 17 side and the loop portion 12 may be provided on the frame portion 8 side. Further, by disposing the plurality of loop portions 12 evenly distributed with respect to the pressing portion 9, it is possible to disperse the setting force of the frame portion 8 and the pressing portion 9, so that the impact due to the opening / closing operation of the frame portion 8 or the like is prevented. Even when the pressing portion 9 is received, the pressing portion 9 is prevented from peeling off locally, and when the pressing portion 9 is removed, strong stress is not locally applied. Further, even when the attachment / detachment is repeated for maintenance, it is possible to surely attach / detach without damaging the elastic member 11 and without uneven bias of the adhesive force.

Next, a method for attaching and detaching the frame portion 8 and the pressing portion 9 will be described with reference to FIGS. 4 and 5. First, a method of mounting the pressing portion 9 on the frame portion 8 will be described.
As shown in FIG. 4, when the pressing portion 9 is attached to the frame portion 8, first, the pressing portion 9 is placed on the contact glass 20 and moved in the A direction and the B direction, and the scale in each direction is moved. 13 and the gap is secured. Then, while pressing the front side (right side in the drawing) of the pressing portion 9 with one hand, the frame portion 8 is lowered toward the contact glass 20 from the position shown in FIG. 4, and the side of the frame portion 8 on the hinge portion 10 side. Hook-and-loop fastener (including hook part 19)
When it is confirmed that is closely attached to the surface fastener (including the loop portion 12) on the pressing portion 9 side, the hand holding the front portion of the pressing portion 9 is released, and further the frame portion 8 is lowered to press the frame portion 8 and The portion 9 is completely brought into close contact (closed state), and the pressing portion 9 is attached to the frame portion 8 by all surface fasteners. According to this method, displacement is less likely to occur as compared with the method of directly attaching the pressing portion 9 to the frame portion 8, the pressing portion 9 does not interfere with the scale 13 when the document pressure plate is closed, and the scale 13 It can be pressed without a gap between the side surface and the pressing portion 9.

In particular, on the pressing portion 9 side, the elastic member 1
Since the loop portion 12 of the hook-and-loop fastener is attached onto the flexible film 17 via the flexible film 17, the frame portion 8 can be received by the sheet surface of the flexible film 17, as described above.

When the loop portion 12 of the surface fastener is directly attached to the elastic member 11 according to the conventional technique, when the frame portion 8 is pressed against the loop portion 12 on the elastic member 11, the The loop portion 12 is pressed against the contact glass 20 side. Here, the elastic member 1
Since the pushing back force of No. 1 toward the frame portion is small, the hook portion 19 on the frame portion 8 side cannot be reliably attached.
Therefore, after pressing the entire surface of the frame part 8 against the pressing part 9,
If the original pressure plate is opened and is not pushed into the frame portion 8 from the sheet member 18 side by hand, the hook-and-loop fastener may not be surely attached.

Next, a method for removing the pressing portion 9 from the frame portion 8 will be described. First, as shown in FIG. 5A, the loop portion 12 side of the uppermost surface fastener is pulled in the direction of the arrow in FIG. In the pressing portion 9 of the present embodiment, since the flexible film 17 is divided and arranged on the elastic member 11 as described above, it can be easily peeled off. Here, since the sheet member 18 has an elastic force that can withstand the bending of the pressing portion 9, it does not bend when the pressing portion 9 is removed.

As described above, the hinge portion 10 is arranged from the highest position thereafter.
The hook-and-loop fastener can be reliably and safely peeled away toward and the pressing portion 9 can be reliably removed from the frame portion 8 (FIGS. 5A, 5B, and 5C).

In the prior art, for example, the loop portion 12 of the surface fastener is directly attached to the elastic member 11, so that when the loop portion 12 is removed, the elastic force of the elastic member 11 is more than the suction force of the loop portion 12. Is small, the loop portion 12 may leave the elastic member 11 and remain held on the hook portion 19 side. Further, when the original pressure plate is to be opened from the closed state, as described in the above-mentioned conventional technique, the contact force between the contact glass 20 and the pressing portion 9 causes the pressing portion 9 to be pulled toward the contact glass 20 side. However, since the frame portion 8 moves away from the contact glass 20, stress is generated in the loop portion 12 and the hook portion 19 of the adhesive portion. As a result, a similar phenomenon occurs, and the loop portion 12 of the pressing portion 9 is peeled off and held by the hook portion 19 of the frame portion 8.

On the other hand, in this embodiment, since the flexible film 17 is interposed, it is possible to prevent the loop portion 12 from peeling from the flexible film 17 even under the above-mentioned operating conditions. Moreover, since the flexible film 17 is a sheet member extending in the direction perpendicular to the A direction, tension is applied not only to the loop portion 12 but also to the entire sheet, and the flexible film 17 is peeled off from the elastic member 11. Can also be prevented.

As described above, in the image reading apparatus of this embodiment, the sheet member 18 in contact with the document 1 placed on the contact glass 20, the sheet member 18, and the sheet member 18 and the frame unit are provided on the pressing portion 9 of the document pressing plate. Elastic member 1 arranged between 8
1, a plurality of flexible films 17 arranged between the elastic member 11 and the frame portion 8 and extending in a direction perpendicular to the A direction, and attachment / detachment for attaching / detaching the flexible film 17 and the frame portion 8 Since the tapes (including hook-and-loop fasteners) 12 and 19 are provided, the contact glass 20 and the pressing portion 9 are evenly adhered to each other, and the stress on the adhesive surface between the elastic member 11 and the frame portion 8 is reduced during the opening operation. In addition, the impact of the contact glass 20 can be reduced and the contact glass 20 can be easily opened.

[Second Embodiment] FIG. 6 shows a main portion of an image reading apparatus according to a second embodiment of the present invention. This is different from the first embodiment in that the surface of the pressing portion 9 of the original pressing plate is roughly processed, and this surface is contact glass 20.
The difference lies in that a sheet member 18 in contact with the original 1 placed above and an elastic member 11 arranged between the sheet member 18 and the frame portion 8 are provided. With this configuration,
A space 21 is provided between the contact glass 20 and the sheet member 18.
Therefore, the effect of facilitating the opening operation of the document pressure plate by appropriately reducing the adhesive force between the contact glass 20 and the pressing portion 9 is obtained.

As shown in FIG. 6, polishing is performed on the entire pressing side of the sheet member 18, and voids 21 are formed on the surface of the sheet member 18 by this polishing process. The gap 21 allows air to enter the gap between the contact glass 20 and the sheet member 18, so that the sheet member 18 can be prevented from coming into close contact with the contact glass 20 when the document pressure plate is opened. Here, if the space 21 is too large, the space 21 may be shaded when reading a document. Conversely, if it is too small, it is difficult for air to enter and the sheet member 18 may adhere to the contact glass 20. Therefore, it is preferable to perform the polishing process so that the shadow does not appear when the document is read.

By thus focusing on the sheet member 18 in contact with the contact glass 20, when the original pressure plate is opened, the pressing portion 9 is brought into close contact with the contact glass 20 side as in the conventional case, and the pressing portion 9 side. It is possible to prevent application of a force that leaves the loop portion 12 on the frame portion 8 side.
Therefore, unlike the first embodiment, the original document pressure plate can be easily opened without attaching the loop portion 12 on the elastic member 11 via the flexible film 17, and the original document pressure plate having high reliability is also provided. Can be realized. For example, the loop portion 12 may be directly attached to the elastic member 11.

In the first embodiment, attention is paid to the adhesion and elastic force between the pressing portion 9 of the original pressure plate and the frame portion 8 so that the opening operation can be easily performed even when the original pressure plate is in close contact with the contact glass 20. Although the configuration is adopted, the flexible film 17 of the first embodiment may be applied to the second embodiment. With this configuration, the original can be reliably brought into close contact with the contact glass 20 when reading the original.

Further, since the contact glass 20 on the frame open end side in the direction opposite to the hinge portion 10 side is outside the normal document reading range, the polishing process of the sheet member 18 for the outside of the document reading range is performed on the document reading range. The roughening may be performed more coarsely, and the polishing process may be performed within the original reading range according to the second embodiment. With this configuration, the load at the beginning of opening is reduced, so that the document pressure plate can be opened more easily.

[Third Embodiment] FIG. 7 shows a third embodiment of the present invention.
2 shows a main part of the image reading apparatus according to the embodiment. here,
(A) shows the pressing portion 9 attached to the frame portion 8 of the document pressure plate, and (b) shows the structure of the frame portion 8 of the document pressure plate. This is different from the first embodiment in that the pressing member 9 of the original pressure plate is divided into a plurality of parts, and an elastic member 11a is attached with a sheet member 18 that comes into contact with the original placed on the contact glass 20, The difference is that 11b is provided. With this configuration, the divided elastic members 11a and 11
In order for b to follow the thickness and shape of the original pressed against the sheet member 18, the contact glass 20
As a result, it is possible to obtain an effect that the original can be closely attached without unevenness. It should be noted that this embodiment has substantially the same configuration as that of the first embodiment.

In FIGS. 7 and 8, a pressing portion 9 for pressing the original is detachably attached to the frame portion 8 of the original pressing plate according to the first embodiment. The original pressure plate is mounted so as to be openable / closable with respect to the contact glass 20 surface (original surface) on the upper portion of the main body by a hinge portion 10 (shown in FIG. 8) connecting the frame portion 8 and the main body of the image reading apparatus. There is. Further, the frame portion 8 is divided into a first frame portion 8a and a second frame portion 8b, and the first frame portion 8a is configured to be rotatable in the ab direction by a connecting member such as a hinge. By opening the frame portion 8 with respect to the original surface of the contact glass, the original can be placed on the contact glass or removed, and by closing the frame portion 8 with respect to the original surface,
The original can be pressed against the contact glass. Here, the rotation fulcrum 32 of the first frame portion 8a is rotated more than the center of the open end (left side in FIG. 8) of the frame portion 8 and the rotation fulcrum 10a of the hinge portion 10. Support point side (connecting end side)
Is set to. By doing so, the second frame portion 8b bends when a cut and pasted original or book original is pressed against the contact glass, and the pressing on the rotation fulcrum side is smaller than the pressing on the open end side. According to the shape of the cut-and-pasted original or book original, it can be pressed evenly. A rib for reinforcing the frame strength is provided on the bottom surface of the frame portion 8 (the surface facing the contact glass when pressing the document). Further, a cubic elastic member 31 made of sponge or the like is joined to the bottom surface so as to face a loop portion 12 of a surface fastener described later, and at least one surface of the elastic member 31 is in contact with the rib. Further, a hook portion (hook-shaped projection portion of the surface fastener) 19 of the surface fastener (velcro tape (registered trademark)) 19 is adhered to each of the surfaces of the elastic member 31 facing the loop portion 12 of the surface fastener described later. ing. The hook portion 19 has the same area as the adhesive surface of the elastic member 31, and is set to have a predetermined area larger than that of the loop portion 12 of the surface fastener provided on the flexible member 17, which will be described later. This is because the hook portion 19 of the surface fastener is superior to the loop portion 12 in durability, and the pressing portion 9 is replaced in maintenance, so that the hook portion 19 having excellent durability is provided on the frame portion 8 side. In addition, in order to flexibly cope with variations in parts, the area of the hook portion 19 is set to the loop portion 12
It is a predetermined amount larger than the area. The thickness of the elastic member 31 is set to such an extent that the hook-shaped projection protrudes from the rib end surface when the hook portion 19 of the surface fastener is bonded. This is to prevent an excessive contact pressure (pressure) when the hook portion 19 and the loop portion 12 of the surface fastener are in contact with each other.

The sheet member 18 of the pressing portion 9 is made of PE.
It is formed of T or the like, and when reading a document, a white one is used so that the periphery of the document is not printed black. In addition, the sheet member 18 has a predetermined amount and area smaller than that of the sheet member 18 and is divided into elastic members 11.
a and 11b are adhered. This elastic member 11a, 1
1b is made of a highly elastic material such as sponge, and is attached to the sheet member 18 with a double-sided tape. Further, the divided positions of the elastic members 11a and 11b correspond to the position of the rotation fulcrum 32 of the frame portion 8a and follow the bending of the frame portions 8a and 8b (a direction and b direction in FIG. 8). There is. Here, the length L ₂ from the rotation fulcrum 10a of the frame portion 8 to the bending position (divided position) of the frame portion 8b, and the frame portion 8
The relationship with the length L ₁ from the bent position of b to the open end of the frame portion 8 is set so that L ₁ > L ₂ . With such a configuration, the pressing portion 9 is made into the frame portion 8
After being attached to the frame, since the position of the original is moved while the pressing portion 9 is pressing the original, the frame portion 8a is moved to b.
When it is rotated in the direction, air is gradually introduced from the open end side of the frame portion 8 between the contact glass 20 and the sheet member 18 to reduce the pressure, so that the contact force between the contact glass 20 and the pressing portion 9 is increased. If necessary, reduce the number to facilitate the movement of the document.

Further, the other surface of the elastic members 11a and 11b (the surface facing the frame portion 8) which is not joined to the sheet member 18 has a predetermined amount and a smaller area than the elastic members 11a and 11b. And flexible material (including flexible film) consisting of film sheets divided into strips
17 is glued. The longitudinal direction of the plurality of flexible films 17 is perpendicular to the opening / closing direction of the frame portion 8.
The longitudinal direction of the plurality of flexible films 17 may be horizontal to the opening / closing direction of the frame portion 8. Alternatively,
The plurality of flexible films 17 may be arranged so as to be adjacent to each other at a predetermined interval in the horizontal direction and the vertical direction. Further, the plurality of flexible films 17 are made of a material (for example, mylar) having a smaller elastic force due to a force in the direction perpendicular to the pressing surface against the frame portion 8 than the elastic member 11. Further, the respective flexible films 17 are attached to the elastic member 11 with a double-sided tape or adhered with an adhesive so as to be adjacent to each other at a predetermined interval.

Further, each of the flexible films 17 described above is provided with a plurality of loop portions (portions forming the pile surface of the surface fastener) 12 of the surface fastener (velcro tape (registered trademark)). This loop part 12
Is set to be smaller than the flexible film 17 by a predetermined amount and area, and smaller than the hook portion 19 of the surface fastener provided on the rib surface of the frame portion 8 by a predetermined amount and area. As described above, since the loop portion 12 is supported by the flexible film 17, the loop portion 12 is prevented from being peeled off or damaged when being attached to or detached from the hook portion 19. In addition, directly on the elastic member 11 softer than the flexible film 17,
When the loop portion 12 is joined, the elastic member 11 may be damaged when the loop portion 12 is detached from the hook portion 19. Here, as compared with the frame portion 8, a loop portion 12 of a surface fastener, which is easily worn and deteriorated, is provided on the pressing portion 9 side where components are frequently replaced, and the area of the loop portion 12 is set smaller than that of the hook portion 19. Therefore, we are trying to reduce the maintenance cost. Further, in the flexible film 17, the loop portion 12 is
A plurality of them are arranged closer to the center than the ends (four corners) in the vertical and horizontal directions. This is because when the document pressure plate rotates in the d direction and when the frame portion 8a rotates in the b direction,
This is to prevent the four sides of the elastic member 11, that is, the ends of the flexible film 17 from being pulled and peeled off from the elastic member 11 due to the contact force between the contact glass 20 and the pressing portion 9. A plurality of loop portions 12 are arranged closer to the center than the four corners of the elastic member 11 via the flexible film 17. This is to prevent a strong stress from being locally applied by the opening / closing operation of the document pressure plate. Further, this is because when the pressing portion 9 is detached from the frame portion 8 for maintenance or the like, the elastic member 11 is surely attached and detached without being damaged and the adhesive force is not biased.

The method of attaching and detaching the frame portion 8 and the pressing portion 9 is almost the same as that of the first embodiment. That is, when the pressing portion 9 is mounted on the frame portion 8, the pressing portion 9 is placed on the contact glass to secure the gap with the scale 13 for positioning. Next, the frame portion 8 is lowered, and the hook portion 1 of the surface fastener on the frame portion 8b side
When the loop portion 12 and 9 are in close contact, the frame portion 8
A is lowered to completely bring the frame portion 8 and the pressing portion 9 into close contact (closed state). According to this method, the pressing portion 9 does not interfere with the scale 13 when the original pressure plate is closed, and the pressing can be performed without a gap between the side surface of the scale 13 and the pressing portion 9. Further, when removing the pressing portion 9 from the frame portion 8, the original pressure plate is opened, and the upper surface fastener is sequentially peeled downward. Here, since the plurality of flexible films 17 are arranged on the divided elastic members 11a and 11b, they can be easily peeled off. Further, since the sheet member 18 has an elastic force sufficient to withstand the bending of the pressing portion 9, it does not bend when the pressing portion 9 is removed. Further, by interposing the flexible film 17, it is possible to prevent the loop portion 12 of the surface fastener from peeling off from the pressing portion 9 and dropping off. Further, since the flexible film 17 extends in the direction perpendicular to the opening / closing direction of the frame portion 8, when the pressing portion 9 is removed, tension is uniformly applied to the entire sheet-shaped flexible film 17, and the flexible film 17 is flexible. Film 17 is elastic member 11
It can also be prevented from peeling off. Further, the loop portion 12 adhered to the flexible film 17 is pressed against the hook portion 19 protruding from the rib formed on the frame portion 8, so that the pressing portion 9 has a uniform height.

Further, in the present embodiment, the case where the frame portion 8 and the pressing portion 9 are composed of a combination of a plurality of parts has been described, but in the present invention, in addition to this, the frame portion 8 and the pressing portion 9 are one part. Even when configured, the same effect can be obtained. Further, in the present embodiment, the type in which the frame portion 8 and the pressing portion 9 are bent in the middle has been described, but the present invention is not limited to this, and the same effect can be obtained even in the type in which the frame portion 8 and the pressing portion 9 are not bent. Is obtained.

Further, in the present embodiment, the length L ₂ from the rotation fulcrum 10a of the frame portion 8 to the bent position (divided position) of the frame portion 8b and the open end of the frame portion 8 from the bent position of the frame portion 8b. The case where the relationship with the length L ₁ is set so that L ₁ > L ₂ has been described. However, the present invention also includes the elastic member 11a.
The relationship between the hardness H ₂ of the elastic member 11b and the hardness H ₁ of the elastic member 11b is H
The same effect can be obtained by setting ₁ > H ₂ . Here, the elastic member 11a and the elastic member 1
For the hardness test of 1b, for example, a spring type hardness tester standardized by "SRIS 0101" of the Japan Rubber Association standard is used, and the spring load measured in this hardness test is applied to the hardness H ₁ mentioned above. , H ₂ .

Further, in each of the above-described embodiments, the case where the present invention is applied to the image reading apparatus has been described, but the present invention can be applied to an image forming apparatus in addition to the same effect. . In this case, the image reading device is further provided with an image forming unit. In this image forming unit, a drum-shaped photosensitive member is centered, and a charging charger, a writing unit, a developing unit, a transfer charger, a separation charger, etc. are arranged around the photosensitive member in the order of steps of the electrophotographic process. ing. The writing unit constitutes a laser writing optical system including a laser output unit (including a laser diode and a polygon mirror), an imaging lens, a mirror and the like.

The flexible film 17 or the sheet member 18 is included in the flexible member, and the surface fastener (including the loop portion 12 and the hook portion 19) is included in the attaching / detaching means.

[0060]

As described above, according to the present invention, the pressing portion for pressing the original placed on the contact glass of the main body of the image reading apparatus is divided into a plurality of parts and is placed on the contact glass. An elastic member provided with a sheet member that comes into contact with the placed original is provided, and the divided elastic member is deformed according to the thickness and shape of the original pressed by the sheet member, whereby the contact glass and the (EN) Provided are a document pressure plate, an image reading device, and an image forming apparatus, which have an excellent effect that the pressing parts can be brought into close contact with each other without unevenness and stress on an adhesive surface between the pressing part and the frame part can be reduced during the opening operation. Is something that can be done.

[Brief description of drawings]

FIG. 1 is an exploded view of a document pressure plate according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of a main part of the image reading apparatus according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a main part of the image reading apparatus according to the first embodiment of the present invention.

FIG. 4 is a perspective view of a main part of the image reading apparatus according to the first embodiment of the present invention (when a document pressure plate is attached).

FIG. 5 is a diagram showing a method of removing a pressing portion of a document pressure plate according to the first embodiment of the present invention.

FIG. 6 is a side sectional view of a main part of an image reading apparatus according to a second embodiment of the present invention.

FIG. 7 is a perspective view of a main part of an image reading apparatus according to a third embodiment of the present invention.

FIG. 8 is a side sectional view of an essential part of an image reading apparatus according to a third embodiment of the present invention.

[Explanation of symbols]

1 manuscript 8, 8a, 8b Frame part 9 Pressing part 10 Hinge part 11, 11a, 11b Elastic member 12, 19 Detachable tape (velcro fastener) 13 scale 17 Flexible film 18 sheet members 20 contact glass 21 void

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshiaki Nagao             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh F-term (reference) 2H012 CB02 CB03                 5C062 AA05 AB02 AB17 AD02 AD06                 5C072 AA01 BA13 LA02 LA07 LA20                       XA01

Claims (19)

[Claims] 1. A frame unit which is openably and closably connected to a main body of an image reading apparatus and which is vertically divided with respect to an opening and closing direction, and an original placed on a contact glass of the main body of the image reading apparatus is pressed. And a pressing unit for attaching and detaching the pressing unit to and from the frame unit. The pressing unit is divided into a plurality of sheets and is in contact with the original placed on the contact glass. An original pressure plate comprising an elastic member having a member attached thereto. 2. The manuscript pressure plate according to claim 1, wherein the elastic member is divided corresponding to a dividing position of the frame portion. 3. The elastic member is divided perpendicularly to the opening / closing direction of the frame portion.
Document pressure plate described in. 4. The length from the connecting end of the frame portion to the dividing position of the frame portion is set to be shorter than the length from the dividing position of the frame portion to the open / close end of the frame portion. The original platen according to claim 2, which is characterized in that. 5. The hardness of the elastic member provided from the connecting end of the frame portion to the divided position of the frame portion is the elastic member provided from the divided position of the frame portion to the open / close end of the frame portion. The original pressure plate according to claim 2, wherein the original pressure plate is set to be softer than the hardness of the original. 6. A frame portion that is openably and closably connected to the main body of the image reading apparatus and is divided perpendicularly to the opening and closing direction, and an original placed on a contact glass of the main body of the image reading apparatus is pressed. And a plurality of attaching / detaching means for attaching / detaching the pressing portion to / from the frame portion, and the pressing portion includes a sheet member in contact with the original placed on the contact glass, and the sheet member. An elastic member disposed between the elastic member and the frame portion and a plurality of flexible members disposed between the elastic member and the frame portion are provided, and each of the plurality of flexible members includes the plurality of flexible members. A manuscript pressure plate having a detaching means attached thereto. 7. The document pressure plate according to claim 6, wherein the flexible member is divided at division positions of the frame portion. 8. The document pressure plate according to claim 7, wherein the flexible member is divided perpendicularly to the opening / closing direction of the frame portion. 9. A frame part that is openably and closably connected to the main body of the image reading device and is divided perpendicularly to the opening and closing direction, and a document placed on the contact glass of the main body of the image reading device is pressed down. And a plurality of attaching / detaching means for attaching / detaching the pressing portion to / from the frame portion. The attaching / detaching means are arranged at six or more locations excluding the four corners of the pressing portion. Document pressure plate. 10. The document pressure plate according to claim 9, wherein the attaching / detaching means is arranged in a central portion of the pressing portion excluding four corners. 11. The attachment / detachment means is provided with a hook portion of a surface fastener adhered to the frame portion and a loop portion of the surface fastener adhered to the pressing portion, and the area of the hook portion and the loop. The document pressure plate according to claim 9 or 10, wherein the areas of the parts are set to be different from each other. 12. A sheet member, which is in contact with an original placed on the contact glass, is arranged between the sheet member and the frame portion, and the frame portion is disposed at a division position of the frame portion. A plurality of elastic members that are vertically divided with respect to the opening / closing direction, and are arranged between the elastic members and the frame portion, and are vertically divided with respect to the opening / closing direction of the frame portion at division positions of the frame portion. The original pressing plate according to claim 11, wherein a plurality of flexible members are provided, and the loop portion of the surface fastener is mounted on each of the plurality of flexible members. 13. The area of the loop portion of the surface fastener is
It is set to be smaller than the area of the flexible member,
The original pressing plate according to claim 12, wherein the loop portion of the surface fastener is arranged in a central portion of the flexible member excluding the four corners. 14. The original document according to claim 11, wherein an elastic member to which a hook portion of the surface fastener is attached is provided on a bottom surface of the frame portion facing the pressing portion. Pressure plate. 15. The original document according to claim 14, wherein the height of the elastic member is set so that the hook portion of the surface fastener projects from the end surface of the rib provided on the frame portion. Pressure plate. 16. The surface of the sheet member, which is in contact with the contact glass, is rough-processed.
16. The document pressure plate according to any one of items 1 to 15. 17. The document pressure plate according to claim 16, wherein the surface roughness of the sheet member is different between the connecting end side and the opening / closing end side of the frame portion. 18. An image reading apparatus provided with the original pressure plate according to claim 1. 19. An image forming apparatus comprising the document pressure plate according to claim 1.