JP4852010B2 - Image reading apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an image reading apparatus and an image forming apparatus provided with the image reading apparatus.

  As shown in FIG. 6, the conventional image reading apparatus 100 places the document G on the contact glass 101, butts the document edge g against the document abutting surface 105 of the outer cover 103, and places the document G on the pressure plate 107. The original G is brought into close contact with the contact glass 101 by pressing from above with the provided background plate 109.

  In such an image reading apparatus 100, the background plate 109 is attached to the pressure plate 107 so that a gap L is left between the document abutting surface 105 and the background plate 109 when the pressure plate 107 is closed. Is prevented from interfering with the document abutting portion 103 having the document abutting surface 105. However, the document edge g existing in the gap L between the document abutting surface 105 and the background plate 109 cannot be pressed against the contact glass 101 by the background plate 109. g rises and cannot be brought into close contact with the contact glass 101. As a result, the image quality deteriorates, such as an image on the document edge g being blurred.

  With respect to such a problem, in Patent Document 1, a background plate is detachably provided on the pressure plate, the background plate removed from the pressure plate is placed against the original abutting surface and placed on the contact glass, and then the pressure plate is pressed down. Thus, the background plate is attached to the pressure plate by bonding with a planar fastener. By thus positioning and attaching the background plate to the pressure plate with high accuracy, no gap is generated between the document abutment surface and the background plate when the document is pressed by the background plate.

Japanese Patent No. 3677726

  However, in Patent Document 1, a work process for accurately positioning the background plate on the pressure plate with respect to each device is required, and since the background plate is detachable, the background of the pressure plate with repeated opening and closing of the pressure plate is required. There is a possibility that the position of the board is displaced and the position of the background board needs to be adjusted each time.

  The present invention can improve image quality by preventing the edge of the document placed on the contact glass from floating from the contact glass without requiring accuracy in positioning the background plate with respect to the pressure plate. It is an object of the present invention to provide an apparatus and an image forming apparatus provided with the image reading apparatus.

  In order to solve the above-mentioned problem, the invention described in claim 1 is characterized in that a document edge is abutted against the document abutting portion, the document is placed on the contact glass, and the document is placed on the contact glass with a background plate provided on the pressure plate. An image reading apparatus that reads an image by pressing to an elastic member that movably connects the background plate to the pressure plate along the pressure plate surface, an operation unit that moves the background plate, and the moved background plate is locked. And a locking portion, and after pressing the document with the background plate, the background plate is moved by the operation of the operation portion and brought into contact with the document abutting portion so that the document edge is brought into close contact with the contact glass.

  According to the second aspect of the present invention, an image is read by placing a document on the contact glass with the document abutting portion abutted against the document abutting portion, and pressing the document against the contact glass with a background plate provided on the pressure plate. An elastic member for connecting the background plate to the pressure plate movably along the pressure plate surface, and a guide for guiding the background plate to a position where the background plate comes into contact with the document abutting portion when the document is pressed by the background plate. And the guide is locked at a position where the background plate is brought into contact with the document abutting portion.

  In the invention described in claim 3, in the invention described in claim 2, the guide is an engaging portion provided on one of the exterior cover or the background plate for holding the contact glass, and the engaging portion has an inclined surface. And the engaged portion provided on the other side moves along the inclined surface to move the background plate toward the document abutting portion.

  In the invention described in claim 4, in the invention described in claim 2, the guide is an inclined surface provided in the document abutting portion, and the inclined surface is inclined with the center side of the contact glass facing downward. The background plate is guided to the end surface of the document abutting portion while the edge of the background plate is in contact with the inclined surface.

    A fifth aspect of the present invention is an image forming apparatus provided with the image reading apparatus according to any one of the first to fourth aspects.

  According to the present invention, when the original is pressed with the background plate, the background plate is moved to the position where it abuts against the document abutting portion and is locked. Hold down. Therefore, even if the background plate is not accurately positioned with respect to the pressure plate, the edge of the document can be pressed against the contact glass with the background plate. Since the entire surface of the original can be brought into close contact with the contact glass without the edge of the original rising from the contact glass, the image quality can be improved. In addition, since the background plate is moved as necessary to contact the document abutting portion when reading the document, it is not necessary to accurately position the background plate with respect to the pressure plate.

  The first embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1A is a longitudinal sectional view showing a state before the background plate of the image reading apparatus according to the present embodiment is moved, and FIG. 1B is a longitudinal section showing the operation of the operation unit according to the present embodiment. FIG. 1C is a longitudinal sectional view showing a state after the background plate of the image reading apparatus according to the present embodiment is moved, and FIG. 2 is a plan view of the image reading apparatus according to the present embodiment. FIG. 3 is a longitudinal sectional view showing a schematic configuration of the image forming apparatus according to the present embodiment.

  As shown in FIG. 3, the copying machine (image forming apparatus) 12 according to the present embodiment includes a recording unit 1 that records on a sheet (recording medium) 61, a sheet feeding unit 55 that supplies the sheet 61, and a sheet. A paper discharge unit 57 for discharging and an image reading device 7 for reading an image of the original G are provided, and an image of the original read by the image reading device 7 is recorded on the paper 61 by the recording unit 1.

  As shown in FIG. 1, the image reading device 7 includes a contact glass 1, a document abutting surface 3 that abuts the document edge, a document abutting portion 8 having the document abutting surface 3, and a document abutting portion 8. The provided exterior cover 2 and a cover 11 (see FIG. 3) that covers the contact glass 1 are provided. The document abutting portion 8 is provided on the exterior cover 2 and protrudes on the contact glass 1. The document abutting surface 3 is an end surface of the document abutting portion 8.

  The cover 11 includes a pressure plate 32, a background plate 43, a coil spring (elastic member) 5 that connects the pressure plate 32 and the background plate 43, an operation lever (operation unit) 45 that moves the background plate 43, and an operation lever 45. And a planar fastener (locking portion) 47 for locking the.

  The pressure plate 32 is supported on the exterior cover 2 by a hinge 6 so as to be freely opened and closed, and includes a guide hole portion 49 that guides the movement of the operation lever 45. The background plate 43 is connected to the pressure plate 32 by a coil spring 5.

  The coil spring 5 has one end 9 a attached to the upper surface 13 of the background plate 43 and the other end 9 b attached to the lower surface 15 of the pressure plate, and connects the background plate 43 and the pressure plate 32. Four identical coil springs 5 are arranged at a predetermined distance from each other between the background plate 43 and the pressure plate 32, and the background plate 43 is movable along the pressure plate surface of the pressure plate 32.

  As shown in FIG. 1, the operating lever 45 has an L-shaped longitudinal section, and includes a first portion 17 that is erected and a second portion 19 that extends along the pressure plate, and the second portion 19. Extends to the side away from the background plate 43.

  As shown in FIG. 1B, the planar fastener 47 includes a locked portion 29 provided on the lower surface of the second portion 19 of the operation lever 45 and a locking portion 31 provided on the upper surface of the pressure plate 32. It is configured. The locked portion 29 is locked when it comes into contact with the locking portion 31, and it is possible to unlock the planar fastener 47 by picking up and lifting the second portion 19 of the operation lever 45. It can be done.

  Accordingly, the background plate 47 can be locked to the initial position (position before the movement of the background plate) 37 by the planar fastener 47 and moved to the initial position 37 by moving the operation lever 45 against the elastic force of the coil spring 5. The background plate 43 can be locked by the planar fastener 47 after the background plate 43 is moved to a position 39 where it abuts against the document abutting surface 3. Furthermore, when the latch of the planar fastener 47 is released, the background plate 43 returns to the initial position 37 by the elastic force of the coil spring 5.

  Here, the operation of the copying machine 12 according to the present embodiment will be described with reference to FIGS. The document edge is abutted against the document abutting surface 3, the document G is set on the contact glass 1, and the pressure plate 32 is closed (see FIG. 1A). Unlocking the planar fastener 47 (see FIG. 1B) moves the operating lever 45 to bring the one end surface 33 of the background plate 43 into contact with the document abutting surface 3. After the background plate is locked by the planar fastener 47, the image of the document 5 is read by the image reading unit 59 (see FIG. 3) of the image reading device 7 (see FIG. 1 (c)). On the other hand, a sheet (recording medium) 61 is supplied from the sheet feeding unit 55, conveyed to the recording unit 1 to record an image, and discharged to the sheet discharge unit 57 (see FIG. 3). Thereafter, the image of the original G is read, and the locking of the surface fastener 47 is released, and the background plate 43 is returned to the initial position 37.

  Below, the effect of 1st Embodiment of this invention is demonstrated. According to the present embodiment, after the original G is pressed by the pressure plate 32, the background plate 43 is moved to the position 39 in contact with the original abutting surface 3 by the operation lever (operation part) 45, and the surface fastener (engagement). The original plate G is pressed while the background plate 43 is in contact with the original abutting surface 3. Therefore, since the document edge g can be pressed against the contact glass 1 by the background plate 43, the document edge g of the document G does not rise from the contact glass 1, and the entire surface of the document G is brought into close contact with the contact glass, thereby improving the image quality. Can be made.

  Since the background plate 43 is moved and brought into contact with the document abutting surface 3, it is not necessary to accurately position the background plate 43 with respect to the pressure plate 32 in order to bring the background plate 43 into contact with the document abutting surface 3.

  Since the background plate 43 can be locked to the initial position 37 by the planar fastener 47, the background plate 43 can be prevented from interfering with the document abutting portion 8, and the engagement with the locking portion 31 of the planar fastener 47 can be prevented. Since it is easy to unlock the stopper 29, the background plate 43 can be easily locked and released.

  The image reading apparatus 7 according to the present embodiment can be provided in a copying machine (image forming apparatus) 12.

  Next, another embodiment of the present invention will be described. In the following description, parts having the same operational effects as those of the first embodiment described above are denoted by the same reference numerals, and the parts thereof are described. Detailed description will be omitted, and the following description will mainly focus on differences from the first embodiment described above.

  The second embodiment of the present invention will be described below. In the present embodiment, as shown in FIG. 4A, the background plate 43 includes a tapered convex portion (engaged portion) 53, and the exterior cover 2 is a concave portion that guides the tapered convex portion 53 ( (Engagement part, guide) 69 is provided.

  The tapered convex portion 53 is a triangular prism having a triangular longitudinal section, and the top 73 of the tapered convex portion 53 is in contact with the inclined surface 75 of the concave portion 69 on the contact glass 1 side when the pressure plate 32 is closed. The taper-shaped convex part 53 and the recessed part 69 are arrange | positioned at the background board and the exterior cover so that it may move to the direction of the arrow of the partial enlarged view of (b). In addition, the taper-shaped convex part 53 and the recessed part 69 fit.

  Here, the operation of the image reading apparatus according to the second embodiment will be described. When the pressure plate 32 is closed, first, the top 73 of the tapered convex portion 53 comes into contact with the inclined surface 75 of the concave portion 69 on the contact glass 1 side (see FIG. 4B). The top 73 moves along the inclined surface 75 of the concave portion 69 against the elastic force of the coil spring 5 while being in contact with the inclined surface 75, and the tapered convex portion 53 and the concave portion 69 are in a state where the pressure plate 32 is completely closed. Are fitted (see FIG. 4A). On the other hand, the one end surface 33 of the background plate 43 is moved and locked from the initial position 37 to the position 39 contacting the document abutting surface 3 with the movement of the tapered convex portion 53. Thereafter, when the image of the original G is read and the pressure plate 32 is opened, the background plate 43 returns to the initial position 37 by the elastic force of the coil spring 5.

  According to the present embodiment, when the document G is pressed by the background plate 43, the background plate 43 is guided and locked to the position 39 that contacts the document abutting surface 3 by the recess (engagement portion) 69. Then, the original G is pressed while being in contact with the original abutting surface 3. Therefore, since the document edge g can be pressed against the contact glass 1 by the background plate 43, the entire surface of the document G is brought into close contact with the contact glass 1 without raising the document edge g from the contact glass 1, thereby improving the image quality. Can do. In addition, the background plate 43 can be guided to the position 39 in contact with the document abutting surface 3 with a simple configuration.

  Since the background plate 43 moves and contacts the document abutting surface 3, it is not necessary to position the background plate 43 with respect to the pressure plate 32 with high accuracy in order to bring the background plate 43 into contact with the document abutting surface 3.

  The third embodiment of the present invention will be described below. In the present embodiment, as shown in FIG. 5, the document abutting portion 8 is inclined to guide the end surface 33 of the background plate 43 to a position where it abuts against the document abutting surface (the end surface of the document abutting portion 8) 3. A surface (guide) 75 is provided.

  The inclined surface 75 is continuous with the upper end 79 of the document abutting surface 3 and is inclined with the center side of the contact glass 1 facing down. The background plate 43 is attached to the pressure plate 32 so that the corner 81 of the background plate 43 contacts the inclined surface 75 when the pressure plate 32 is closed.

  Here, the operation of the image reading apparatus according to the third embodiment will be described. When the pressure plate 32 is closed, first, the corner portion 81 of the background plate 43 at the initial position 37 contacts the inclined surface 75, and the corner portion 81 contacts the inclined surface 75 and resists the elastic force of the coil spring 5. Then, it is guided to the upper end 79 of the document abutting surface 3 (see FIG. 5B). When the pressure plate 32 is completely closed, the one end surface 33 of the background plate 43 comes into contact with the document abutting surface 3 and is locked while being urged toward the document abutting surface 3 by the elastic force of the coil spring 5. (See FIG. 5 (a)). Thereafter, when the image of the original G is read and the pressure plate 32 is opened, the background plate 43 returns to the initial position 37 by the elastic force of the coil spring 5.

  According to the present embodiment, it is possible to guide the background plate 43 to the position 39 in contact with the document abutting surface 3 with a simpler configuration than the second embodiment.

  The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the scope of the invention.

In the first embodiment, the planar fastener (locking portion) 47 includes the locking portion 31 and the locked portion 29, but instead of this, the first of the operating lever 45 is provided. A magnet is attached to one end face 41 of the portion 17 and one end face 51 of the pressure plate 32 facing the guide hole 49, and a magnetic material such as iron is attached to the other, and the operation lever 45 is moved to the guide hole 49. The one end surface 51 of the facing pressure plate may be detachable.
In the second embodiment, the tapered convex portion 53 (engaged portion) is provided on the background plate 43 and the concave portion (engagement portion) 69 is provided on the exterior cover 2. The tapered convex portion 53 may be provided on the exterior cover 2, and the concave portion 69 may be provided on the background plate 43.

  In the above embodiment, the coil spring 5 is used as an elastic member, but instead of this, a rubber or resin plate or the like may be used.

(A) is a longitudinal cross-sectional view which shows the state before the movement of the background board of the image reading apparatus which concerns on 1st Embodiment, (b) is a longitudinal cross-sectional view which shows operation | movement of the operation part which concerns on this Embodiment. FIG. 4C is a longitudinal sectional view showing a state after the background plate of the image reading apparatus according to the first embodiment is moved. 1 is a plan view of an image reading apparatus according to a first embodiment. 1 is a longitudinal sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment. (A) is a longitudinal cross-sectional view which shows the state after the movement of the background board of the image reading apparatus which concerns on 2nd Embodiment. (B) is a longitudinal cross-sectional view which shows the movement state of the background board of the image reader which concerns on 2nd Embodiment. (A) is a longitudinal cross-sectional view which shows the state after the movement of the background board of the image reading apparatus which concerns on 3rd Embodiment. (B) is a longitudinal cross-sectional view which shows the movement state of the background board of the image reading apparatus which concerns on 3rd Embodiment. It is a longitudinal cross-sectional view of a state in which a pressure plate of a conventional image reading apparatus is closed.

Explanation of symbols

1 Contact glass 2 Exterior cover 3 Document abutting surface (end surface of the document abutting portion)
5 Coil spring (elastic member)
7 Image reading device 8 Document abutting portion 12 Image forming device 32 Pressure plate 33 One end surface of the background plate (end surface of the background plate)
37 Initial position 43 Background plate 45 Operation lever (operation unit)
47 Surface fastener (locking part)
53 Tapered convex part (engaged part)
69 Recess (engagement part) (guide)
75 Inclined surface (guide)
100 Copying machine (image forming device)
G Document g Document edge

Claims (5)

  An image reading apparatus for reading an image by placing a document on a contact glass with a document abutting portion and placing the document on a contact glass and pressing the document against the contact glass with a background plate provided on the pressure plate. An elastic member movably coupled along the pressure plate surface, an operation portion for moving the background plate, and a locking portion for locking the moved background plate. An image reading apparatus characterized in that a background plate is moved by operation and brought into contact with a document abutting portion so that a document edge is brought into close contact with a contact glass.   An image reading apparatus for reading an image by placing a document on a contact glass with a document abutting portion and placing the document on a contact glass and pressing the document against the contact glass with a background plate provided on the pressure plate. And a guide for guiding the background plate to a position where the background plate comes into contact with the document abutting portion when the document is pressed by the background plate. An image reading apparatus, wherein the image reading apparatus is locked at a position where it abuts against the abutting portion.   The guide is an engagement portion provided on one of the exterior cover or the background plate that holds the contact glass, and the engagement portion has an inclined surface, and the engaged portion provided on the other moves along the inclined surface to move the background. The image reading apparatus according to claim 2, wherein the plate is moved toward the document abutting portion.   The guide is an inclined surface provided in the document abutting portion, and the inclined surface is inclined with the center side of the contact glass facing down, and the background plate is brought into contact with the inclined surface while the edge of the background plate is in contact with the inclined surface. The image reading apparatus according to claim 2, wherein the image reading apparatus is guided to an end surface of the image reading apparatus.   An image forming apparatus provided with the image reading apparatus according to claim 1.

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