JP6682588B2 - Image reading apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an image reading apparatus such as an image scanner and an image forming apparatus provided in an image forming apparatus such as a copying machine, a facsimile machine, and a multi-function peripheral.

  2. Description of the Related Art Conventionally, in image forming apparatuses such as copiers, facsimile machines, and multi-function machines, generally, a document placed on a transparent plate of a document platen having a transparent plate such as transparent glass is surely placed on the document platen. A document pressing device is provided so as to obtain an image of good quality by bringing them into close contact with each other.

  The document pressing device includes a pressing member that covers and presses the document. The pressing member usually includes a document pressing member and an elastic member provided on the document pressing side of the document pressing member to press the document. The document pressing device has a function of uniformly pressing the elastic member against the document placed on the transparent plate of the document table.

  However, in the conventional document pressing device, when an image of a document (especially, a document having gloss such as a photo document) is read, if the pressing force of the elastic member against the document is increased, a gap between the document and the transparent plate is generated. Interference of the light waves reflected on both sides (so-called Newton's ring) causes spots on the read image of the original, and if the pressing force of the elastic member on the original is weakened in order to prevent the spots due to this interference, the original is pressed against the transparent plate. There is an inconvenience that the floating causes a shadow in the read image of the document.

  In this regard, in Patent Document 1, in the surface of the original pressing plate (original pressing member) facing the contact glass (transparent plate of the original placing table), the central portion of this surface is formed to have the maximum thickness, and By arranging the elastic member whose thickness around the central portion is successively or linearly formed to be successively thin, the document pressing plate (document pressing member) is in an open state in Patent Document 2. It has been proposed that a plurality of elastic members that protrude when the document is closed and that closely contact the document when the document is closed prevent misalignment and winding of the document when the document pressing member is opened and closed.

  Further, in Patent Document 3, at least one of the compression amount and the elastic modulus of the pressing member is gradually reduced from the side closer to the hinge portion to the side farther from the hinge portion. It has been proposed to prevent floating.

JP-A-5-27339 Japanese Utility Model Publication No. 62-91635 JP, 2008-152185, A

  However, the inventions described in Patent Documents 1 and 2 prevent the displacement and winding of the document when the document pressing member is opened and closed, and in the invention described in Patent Document 3, the opening and closing side end portion of the document pressing member floats. However, in any case, the spots that may occur in the read image of the original due to the interference of light waves in the gap between the original and the transparent plate, and the read image of the original due to the floating of the original against the transparent plate. No consideration is given to preventing both of the shadows that can occur in the.

  In view of the above, according to the present invention, both spots that may occur in the read image of the document due to interference of light waves in the gap between the document and the transparent member, and shadows that may occur in the read image of the document due to floating of the document on the transparent member. It is an object of the present invention to provide an image reading apparatus and an image forming apparatus capable of effectively preventing the above.

  In order to solve the above-mentioned problems, the present inventor has conducted extensive studies and, as a result, has conducted a plurality of types of prescribed sizes (for example, A3 size, B4 size, A4 size) mounted on a transparent member of a document mounting table having a transparent member. Size, B5 size, A5 size, 2L size, B6 size, A6 size, L size), in an image reading apparatus equipped with a document pressing device for pressing a plurality of types of specified size documents, In the non-document pressing area of the pressing member having the non-document pressing area outside the document pressing area, the pressing force of the document in the document pressing area is partially restricted (decreased), so that the document pressing area of the pressing member is reduced. The pressing force of can be made moderate both in the part regulated by the regulation member and in the non-regulated portion, whereby the light wave in the gap between the document and the transparent member can be suppressed. Spots that may occur in the document image read by Wataru, and found that can effectively prevent both the shadow that may occur in the document image read by the floating of the document to the transparent member, and completed the present invention.

  The present invention is based on such knowledge and provides the following image reading apparatus and image forming apparatus.

(1) Image Reading Device An image reading unit including an original placing table having a transparent member on which an original is placed, an original pressing device provided with an original pressing member for pressing the original placed on the transparent member , An image reading apparatus including: a rotation supporting portion that supports the original document holding device so as to be openable and closable with respect to the image reading portion, wherein the image reading portion includes a non-original document placed outside the transparent member. A loading area is provided, and the document pressing device is provided with a contact piece that partially contacts the non-document loading area when the document pressing apparatus is closed. An image reading apparatus provided within a width of the document pressing member in a direction orthogonal to a rotation axis direction of the unit.

(2) Image forming apparatus An image forming apparatus including the image reading apparatus according to the present invention.

According to the present invention, the contact piece can partially restrict (reduce) the pressing force of the document pressing area on the document in the non-document pressing area. Therefore, the pressing force in the document pressing area can be made appropriate both in the part regulated by the contact piece and in the part not regulated by the contact piece, whereby the document and the transparent member can be separated from each other. It is possible to effectively prevent both spots that may occur in the read image of the document due to interference of light waves in the gap and shadows that may occur in the read image of the document due to floating of the document with respect to the transparent member. .

  In addition, the original pressing area can be made to be an area for pressing the maximum size of the original among the specified sizes, whereby not only the predetermined size smaller than the maximum size can be applied but also the maximum size of the maximum size can be applied. It can also be applied to the original document. These are particularly effective when the original is an original having gloss (for example, a glossy original) such as a photo original.

In the present invention, it is possible to exemplify a mode in which a plurality of the contact pieces are provided in a region corresponding to the non-document placement region on one side with the transparent member in between in the rotation axis direction.

In the present invention, it is possible to exemplify a mode in which the contact pieces are respectively provided in regions corresponding to the non-document placement region on one side and the other side with the transparent member in between in the rotation axis direction.

In the present invention, prior to the contact piece which contacts the Kihi document placing area is central by remote the pivot support portion in said document pressing member in the direction perpendicular to the rotation axis direction of the rotation supporting portion It can be exemplified embodiments are provided.

In the present invention, the sheet presser, in the orthogonal direction, the rotation first and sheet presser provided on the supporting portion side, a second sheet presser, which is freely bent with respect to the first sheet presser And the contact piece is provided in the first document pressing device.

  In the present invention, it is possible to exemplify a mode in which the rotation support portion is supported so as to be movable in the vertical direction with respect to the image reading portion.

In the present invention, provided in the sheet presser includes an elastic member for pressing the original document, the contact piece can be exemplified embodiment is a projection shape having a hard property.

  As described above, according to the present invention, the spots that may occur in the read image of the original due to the interference of the light waves in the gap between the original and the transparent member, and the floating of the original with respect to the transparent member It is possible to effectively prevent both shadows that may occur in the read image of the document.

FIG. 1 is a schematic cross-sectional view of an image forming apparatus including an image reading device according to an embodiment of the present invention when viewed from the front. FIG. 2 is a schematic plan view of the image reading apparatus mounted on the image forming apparatus shown in FIG. 1, as viewed from above. FIG. 3 is a schematic sectional view of the image reading device shown in FIGS. 1 and 2 as viewed from the front. FIG. 4 is a schematic perspective view of an open state of the document pressing device of the image reading device shown in FIGS. 1 to 3 as viewed obliquely from above the front. FIG. 4 is a schematic cross-sectional view showing a contact glass, a supporting portion, and a regulating member portion when the document pressing device of the image reading device shown in FIGS. 1 to 3 is closed. FIG. 4A is a schematic cross-sectional view showing a regulating member portion provided in the image reading apparatus, and FIG. 6A is a diagram showing a state where the document is not pressed at a portion where the pressing force is not regulated by the regulating member; FIG. 6 is a diagram showing a state in which a document is pressed by an elastic member via a contact member in a portion where the pressing force is not regulated by the regulating member, and FIG. 6C is a portion where the pressing force is regulated by the regulating member. FIG. 4D is a diagram illustrating a state in which the original is not pressed, and FIG. 6D is a diagram illustrating a state in which the document is pressed by the elastic member via the contact member at the portion where the pressing force is restricted by the restriction member. FIG. 3 is a schematic bottom view of the document pressing device according to the first embodiment of the present embodiment as viewed from the bottom surface. FIG. 8 is a schematic plan view of a state in which the document pressing device shown in FIG. 7 is pressing a document as viewed from above. FIG. 9 is a schematic cross-sectional view showing a state in which the document pressing device shown in FIG. 7 is separated from the image reading device main body, FIG. 8A is a diagram showing a state seen from the direction A shown in FIG. 8, and FIG. FIG. 9 is a diagram showing a state viewed from the direction B shown in FIG. 8. FIG. 9 is a schematic bottom view of the document pressing device according to the second embodiment of the present embodiment as viewed from the bottom surface. FIG. 11 is a schematic plan view of a state in which the document pressing device shown in FIG. 10 is pressing a document as viewed from above. FIG. 11 is a schematic cross-sectional view showing a state in which the document pressing device shown in FIG. 10 is separated from the image reading device main body, FIG. 11A is a diagram showing a state seen from the direction A shown in FIG. 11, and FIG. FIG. 12 is a diagram showing a state viewed from the direction B shown in FIG. 11. FIG. 9 is a schematic bottom view of the document pressing device according to the third embodiment of the present embodiment as viewed from the bottom surface. FIG. 14 is a schematic plan view of a state in which the document pressing device shown in FIG. 13 presses a document, as viewed from above. FIG. 15 is a schematic cross-sectional view showing a state in which the document pressing device shown in FIG. 13 is separated from the image reading device main body, and is a diagram showing a state viewed from the direction A shown in FIG. 14. FIG. 3A is a schematic view showing a state in which the regulating member is a rigid protrusion-shaped member in the document pressing device, and the pressing member is closed. FIG. FIG. 6B is a diagram showing an example provided, FIG. 6B is a diagram showing an example in which the regulation member is provided on the support portion in the outer region of the document placing table, and FIG. FIG. 6 is a diagram showing an example provided in both the non-document pressing region of the member and the supporting portion in the region outside the document placing table. Evaluation of spots that can occur in the scanned image of the document due to interference of light waves in the gap between the document and the contact glass, and the state of generation of shadows (fogging) that can occur in the scanned image of the document due to floating of the document on the contact glass It is a chart showing a result.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below is an example in which the present invention is embodied, and does not limit the technical scope of the present invention.

  FIG. 1 is a schematic sectional view of an image forming apparatus 400 including an image reading apparatus 100 according to an embodiment of the present invention as viewed from the front.

  An image forming apparatus 400 shown in FIG. 1 records an image of a document G on an image reading device 100 and an image of the document G read by the image reading device 100 or an image received from the outside in a color or a single color such as plain paper. The image forming apparatus main body 400d for recording and forming on a sheet is provided, and the image reading apparatus 100 is mounted on the upper surface of the image forming apparatus main body 400d.

[Overall Configuration of Image Forming Apparatus]
The image forming apparatus main body 400d includes an exposure device 1, a developing device 2 (2a, 2b, 2c, 2d), a photosensitive drum 3 (3a, 3b, 3c, 3d) acting as an image carrier, and a charger 5 (5a, 5b, 5c, 5d), a cleaner device 4 (4a, 4b, 4c, 4d), an intermediate transfer belt device 8 including an intermediate transfer roller 6 (6a, 6b, 6c, 6d) acting as a transfer portion, a fixing device 12, The sheet transport device 50 includes a sheet feeding tray 10 that functions as a sheet feeding unit, and a sheet discharging tray 15 that functions as a sheet discharging unit.

  The image data handled by the image forming apparatus main body 400d corresponds to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y), or a single color (for example, black). It corresponds to a monochrome image using. Therefore, the developing device 2 (2a, 2b, 2c, 2d), the photosensitive drum 3 (3a, 3b, 3c, 3d), the charger 5 (5a, 5b, 5c, 5d), the cleaner device 4 (4a, 4b, 4c, 4d) and four intermediate transfer rollers 6 (6a, 6b, 6c, 6d) are provided so as to form four types of images corresponding to the respective colors, and a of the end symbols a to d is a. Is associated with black, b is associated with cyan, c is associated with magenta, and d is associated with yellow, thus forming four image stations. In the following description, the trailing symbols a to d will be omitted.

  The photoconductor drum 3 is disposed substantially at the center of the image forming apparatus main body 400d in the vertical direction. The charger 5 is a charging unit for uniformly charging the surface of the photoconductor drum 3 to a predetermined potential, and includes a contact type roller type or brush type charger, and a charger type charger. .

  Here, the exposure device 1 is a laser scanning unit including a laser diode and a reflection mirror, and exposes the surface of the charged photosensitive drum 3 according to image data, and the surface thereof is electrostatically charged according to the image data. Form a latent image.

  The developing device 2 develops the electrostatic latent image formed on the photosensitive drum 3 with (K, C, M, Y) toner. The cleaner device 4 removes and collects the toner remaining on the surface of the photosensitive drum 3 after development and image transfer.

  The intermediate transfer belt device 8 arranged above the photoconductor drum 3 includes, in addition to the intermediate transfer roller 6, an intermediate transfer belt 7, an intermediate transfer belt driving roller 21, a driven roller 22, a tension roller 23, and an intermediate transfer belt cleaning. A device 9 is provided.

  Roller members such as the intermediate transfer belt driving roller 21, the intermediate transfer roller 6, the driven roller 22, and the tension roller 23 stretch and support the intermediate transfer belt 7 and support the intermediate transfer belt 7 in a predetermined sheet conveyance direction (in the figure). Move in the direction of the arrow).

  The intermediate transfer roller 6 is rotatably supported inside the intermediate transfer belt 7, and is pressed against the photosensitive drum 3 via the intermediate transfer belt 7.

  The intermediate transfer belt 7 is provided so as to be in contact with each of the photoconductor drums 3, and the toner images on the surface of each photoconductor drum 3 are transferred to the intermediate transfer belt 7 so as to be sequentially superposed and transferred. Toner image) is formed.

  The transfer of the toner image from the photosensitive drum 3 to the intermediate transfer belt 7 is performed by the intermediate transfer roller 6 that is in pressure contact with the inside (back surface) of the intermediate transfer belt 7. A high-voltage transfer bias (for example, a high voltage having a polarity (+) opposite to the charging polarity (−) of the toner) is applied to the intermediate transfer roller 6 in order to transfer the toner image.

  The image forming apparatus main body 400d further includes a secondary transfer device 11 including a transfer roller 11a that functions as a transfer portion. The transfer roller 11a is in contact with the opposite side (outside) of the intermediate transfer belt 7 to the intermediate transfer belt drive roller 21.

  As described above, the toner images on the surfaces of the photoconductor drums 3 are stacked on the intermediate transfer belt 7 to form a color toner image indicated by the image data. The toner images of the respective colors thus stacked are conveyed together with the intermediate transfer belt 7 and transferred onto the recording sheet by the secondary transfer device 11.

  The intermediate transfer belt 7 and the transfer roller 11a of the secondary transfer device 11 are pressed against each other to form a nip area. Further, the transfer roller 11a of the secondary transfer device 11 has a voltage (for example, a polarity (+) opposite to the charging polarity (-) of the toner), for transferring the toner image of each color on the intermediate transfer belt 7 to the recording sheet. High voltage) is applied.

  Further, the secondary transfer device 11 removes and collects the residual toner remaining on the intermediate transfer belt 7 without completely transferring the toner image onto the recording sheet. The intermediate transfer belt cleaning device 9 is provided with, for example, a cleaning blade that comes into contact with the intermediate transfer belt 7 as a cleaning member, and this cleaning blade can remove and collect residual toner.

  The paper feed tray 10 is a tray for storing recording sheets, and is provided below the image forming unit 110 of the image forming apparatus main body 400d. Further, the paper discharge tray 15 provided on the upper side of the image forming unit 110 is a tray for placing printed recording sheets face down.

  Further, the image forming apparatus main body 400d is provided with a sheet conveying device 50 for feeding the recording sheet of the paper feed tray 10 to the paper discharge tray 15 via the secondary transfer device 11 and the fixing device 12. The sheet conveyance device 50 has an S-shaped sheet conveyance path S, and along the sheet conveyance path S, the pickup roller 16, the first separation roller 14a, the second separation roller 14b, each conveyance roller 13, and the pre-registration roller. Conveying members such as the roller pair 19, the registration roller pair 106, the fixing device 12 and the paper discharge roller 17 are arranged.

  The pickup roller 16 is a pickup roller that is provided at the downstream end of the sheet feeding tray 10 in the sheet conveying direction and supplies recording sheets from the sheet feeding tray 10 to the sheet conveying path S one by one. The first separation roller 14a passes the recording sheet between the first separation roller 14a and the second separation roller 14b, separates the recording sheets one by one, and conveys them to the sheet conveyance path S. Each of the transport rollers 13 and the pair of pre-registration rollers 19 are small rollers for promoting and assisting the transport of the recording sheet. Each conveyance roller 13 is provided at a plurality of locations along the sheet conveyance path S. The pre-registration roller pair 19 is provided immediately upstream of the registration roller pair 106 in the sheet conveyance direction, and conveys the recording sheet to the registration roller pair 106.

  The fixing device 12 includes a heat roller 31 and a pressure roller 32. The heat roller 31 and the pressure roller 32 sandwich and convey the recording sheet.

  The heat roller 31 is temperature-controlled so as to have a predetermined fixing temperature, and the recording sheet is thermocompression bonded together with the pressure roller 32, so that the toner image transferred to the recording sheet is melted, mixed, and pressure-contacted to the recording sheet. On the other hand, it has the function of heat fixing. Further, the fixing device 12 is provided with an external heating belt 33 for heating the heat roller 31 from the outside.

  The recording sheet on which the toner images of the respective colors have been fixed is discharged onto the discharge tray 15 by the discharge rollers 17.

  It is also possible to form a monochrome image using at least one of the four image forming stations and transfer the monochrome image to the intermediate transfer belt 7 of the intermediate transfer belt device 8. This monochrome image is transferred to the recording sheet from the intermediate transfer belt 7 and fixed on the recording sheet, like the color image.

  Further, when not only the front (front) surface of the recording sheet but also both sides of the image are formed, after fixing the image on the surface of the recording sheet by the fixing device 12, the recording sheet is ejected from the sheet discharge path 17 of the sheet conveying path S. While the sheet is being conveyed, the paper discharge roller 17 is stopped and then rotated in the reverse direction, the recording sheet is passed through the front / back reversing path Sr to reverse the front and back of the recording sheet, and then the recording sheet is again transferred to the registration roller pair 106. The image is recorded and fixed on the back surface of the recording sheet in the same manner as the front surface of the recording sheet, and the recording sheet is discharged to the paper discharge tray 15.

  It should be noted that, in the image reading apparatus 100 shown in FIG. 1, the reference numerals not described among the attached reference numerals will be described later.

[Overall configuration of image reading device]
FIG. 2 is a schematic plan view of the image reading apparatus 100 mounted on the image forming apparatus 400 shown in FIG. FIG. 3 is a schematic sectional view of the image reading apparatus 100 shown in FIGS. 1 and 2 as viewed from the front. In addition, in FIG. 1 and FIG. 3, a regulating member 370 described later is omitted.

  As shown in FIGS. 2 and 3, the image reading apparatus 100 is an image reading apparatus of a reduction optical system type, and a document G (for example, in addition to a general normal document, glossiness is added by a document fixing method). The original is fixed and the original image is read. The image reading apparatus 100 includes a plurality of types of specified sizes (here, A3 size and B4 size) mounted on the contact glass 201a of the document table 201 having the image reading apparatus main body 100d and the contact glass 201a which is an example of a transparent plate. A document holding device 300 for holding a document G of size, A4 size, B5 size, A5 size, 2L size, B6 size, A6 size, L size) is provided. Here, the 2L size and the L size are sizes mainly used for photographic originals, the 2L size is 127 mm (5 inches) × 178 mm (7 inches), and the L size is 89 mm (3.5 inches) × 127 mm ( 5 inches).

  As shown in FIG. 3, the image reading apparatus main body 100d illuminates an original document G placed on the contact glass 201a through the contact glass 201a while moving the light source unit 210 in the one side Y1 of the sub scanning direction Y. The document reading unit 200 reads the document image by scanning the reflected light from the document G illuminated by the light source unit 210 in the main scanning direction X orthogonal to both the sub-scanning direction Y and the vertical direction Z.

  Specifically, the document reading unit 200 includes a contact glass 201a, a light source unit 210 acting as a scanning body, an optical system driving unit (not shown) for moving the light source unit 210, a mirror unit 203, a condenser lens 204, and photoelectric conversion. An element (here, CCD) 205 is provided, and these members are housed in a metal frame body 202. The light source unit 210 includes a light source 211 that irradiates the original G with light, and a first mirror 230 that guides the reflected light from the original G to the mirror unit 203. The light source 211 includes two light emitting element rows 212a and 212b in which a plurality of light emitting elements are arranged in the main scanning direction X, and light source substrates 213a and 213b on which the two light emitting element rows 212a and 212b are mounted, respectively.

  The contact glass 201a on which the original G is placed is made of a transparent glass plate, and both ends in the main scanning direction X are placed on the frame 202. The document pressing device 300 includes an opening / closing axis Q1 (see FIG. 7, which will be described later) and is located at one end side (specifically, the image reading device body 100d or the image forming apparatus body 400d (here, the image reading device body 100d)). The operation side of the image reading apparatus main body 100d where the operation unit 101 (see FIG. 2) is provided, the front side (front side) is opposite to the other end side (specifically, the operation side is openable and closable). Are pivotally supported by the opening / closing shaft Q1 on the opposite side and the back side (back side). The document pressing device 300 will be described later in detail with reference to FIGS. 4 to 16.

  The mirror unit 203 includes a second mirror 203a, a third mirror 203b and a support member (not shown). The support member supports the second mirror 203a so that the light from the first mirror 230 in the light source unit 210 is reflected and guided to the third mirror 203b. Further, the support member supports the third mirror 203b so as to reflect the light from the second mirror 203a and guide it to the condenser lens 204. The condenser lens 204 condenses the light from the third mirror 203b on the light receiving surface 205d of the photoelectric conversion element 205. The photoelectric conversion element 205 repeatedly scans the light (original image light) from the condenser lens 204 in the main scanning direction X, and outputs an analog signal of one scanning line each time.

  Further, the optical system driving section is provided with a scanner motor (not shown) and a moving mechanism such as a pulley and a wire (not shown) here, and the light source unit 210 is moved at a constant speed in the sub-scanning direction Y by these scanner motor and moving mechanism. And the mirror unit 203 is also moved in the sub-scanning direction Y at a moving speed half the moving speed of the light source unit 210.

  In the image reading apparatus 100 described above, the light source unit 210 irradiates the original G placed on the contact glass 201a of the original placing table 201 with the light from the light source 211 through the contact glass 201a and keeps the light constant. The mirror unit 203 moves to one side Y1 of the sub-scanning direction Y at a speed to scan the image of the document G, and at the same time, the mirror unit 203 moves at half the moving speed of the light source unit 210 to the one side of the sub-scanning direction Y at the same time. Move to Y1.

  The reflected light that is illuminated by the light source unit 210 and reflected from the original G is reflected by the first mirror 230 provided in the light source unit 210, and then is reflected by the second mirror 203a and the third mirror 203b of the mirror unit 203. ° Optical path is changed. The light reflected from the third mirror 203b forms an image on the light receiving surface 205d of the photoelectric conversion element 205 via the condenser lens 204, where the image light of the original is read and converted into an analog signal.

  In the present embodiment, the image reading apparatus main body 100d is provided with an automatic document feeder which automatically conveys the document G and also serves as the document pressing device, instead of the document pressing device 300. The original G is moved by a moving method to read the original image. In this case, the image reading apparatus 100 causes the original reading unit 200 to read the original G conveyed on the one side Y1 in the sub-scanning direction Y so as to pass over the original reading glass 201b by the automatic original feeding apparatus (original reading). A light source unit 210 located below the glass 201b) scans light reflected from the document G illuminated by the light source unit 210 in the main scanning direction while illuminating the document reading glass 201b through the document reading glass 201b to read a document image. You can

[Document holding device]
The document pressing device 300 includes a pressing member 360 that covers and holds the document G of a plurality of types of specified sizes (here, A3, B4, A4, B5, A5, 2L, B6, A6, and L sizes). ing. The pressing member 360 includes a document pressing member (specifically, a document pressing plate) 310, and an elastic member 320 that is provided on the document pressing side of the document pressing member 310 and presses the documents G of a plurality of prescribed sizes. There is.

  It should be noted that, in the document pressing device 300 shown in FIGS. 2 and 3, the reference numerals not described among the attached reference numerals will be described later.

  4 to 16 are schematic diagrams for explaining the document pressing device 300 in the image reading device 100. 4 to FIG. 16, FIG. 4 shows a schematic perspective view of the image reading apparatus 100 shown in FIGS. Note that, in FIG. 4, the position of the regulating member 370 is the position of Example 1 described later. Further, FIG. 5 is a schematic cross-sectional view showing the contact glass 201a, the supporting portion 340, and the regulating member 370 when the document pressing device 300 of the image reading apparatus 100 shown in FIGS. 1 to 3 is closed. .

  In the document pressing device 300 shown in FIGS. 4 to 16, the document pressing member 310 is a plate-shaped housing member and is made of a resin material such as ABS (Acrylonitrile Butadiene Styrene). The document pressing member 310 supports the elastic member 320, and has a size larger than the maximum size (here, A3 size) of the document G placed on the contact glass 201a. Specifically, the document pressing member 310 includes a document pressing member main body 311 (see FIG. 5 and the like), and a plurality of ribs 312 to 312 (see FIG. 5 and the like) erected from the document pressing member main body 311 to the document pressing side. Is equipped with. The ribs 312 to 312 extend along the sub-scanning direction Y, and the elastic members 320 are provided on the ribs 312 to 312. The document pressing member body 311 and the ribs 312 to 312 are integrally formed.

  The document pressing member 310 is pivotally supported by an opening / closing shaft Q1 on the back side so that the front side can be opened and closed.

  In the present embodiment, the document pressing device 300 further includes a hinge part 330 that functions as a rotation support part that supports the document pressing member 310 in an openable and closable manner.

  The hinge section 330 is a pair provided on one side Y1 and the other side Y2 of the sub-scanning direction Y, and main body side members provided on the back side (back side) of the image reading apparatus main body 100d, respectively. 331, and a document pressing member 332 that is provided on the back side (back side) of the document pressing member 310 and that rotates in the opening / closing direction W (see FIG. 9, etc.) with respect to the main body member 331.

  The document pressing member 310 is provided on the image reading apparatus main body 100d such that the opening / closing axis Q1 is movable in the vertical direction Z.

  Specifically, the main body side member 331 is provided so as to be freely inserted into and removed from the image reading apparatus main body 100d. The document pressing side member 332 is rotatably supported by the main body side member 331 by an opening / closing shaft Q1 along the sub-scanning direction Y. Specifically, the main body side member 331 is a rod-shaped member that is inserted into an insertion hole 206 (see FIG. 9 and the like) provided in the image reading apparatus main body 100d along the vertical direction Z. The document pressing member 332 is fixedly provided on the document pressing member 310. The document pressing side member 332 and the document pressing member 310 may be integrally formed.

  Further, the hinge portion 330 is configured to bias the document pressing member 310 toward the document pressing side by a biasing member such as a coil spring. Note that a conventionally known configuration can be used as a configuration for urging the document pressing member 310 toward the document pressing side, and a detailed description thereof will be omitted here.

  In the document pressing device 300 having such a configuration, the main body side member 331 of the document pressing member 310 is inserted into the insertion hole 206 (see FIG. 9 and the like) of the image reading device main body 100d and attached to the image reading device main body 100d. As a result, when the main body side member 331 rotates with respect to the original document pressing side member 332 in a state where the original document pressing member 310 is mounted on the image reading device main body 100d, the original document pressing member 310 opens and closes on the front side with respect to the image reading device main body 100d. be able to. Then, in the document pressing device 300, the pressing member 360 including the document pressing member 310 and the elastic member 320 is applied to the contact glass 201 a of the document placing table 201 by the urging force of the hinge portion 330 to the document pressing side of the document pressing member 310. It can be pressed toward.

  Further, in the present embodiment, the pressing member 360 has the central portion of the document pressing area α1 (see the hatched portion in FIG. 4) in the direction from the front side to the back side (here, the main scanning direction X in the closed state). Alternatively, it has a two-fold structure in which it is foldable around a substantially central portion (here, central portion C, see FIG. 4). Here, the document pressing region α1 is a region (specifically, the elastic member 320) that presses the document G of each specified size (specifically, the maximum size among the specified sizes, here, A3 size).

  More specifically, the pressing member 360 includes a central portion or a substantially central portion (here, the central portion) in the direction (here, the main scanning direction X in the closed state) of the document pressing member 310 from the front side to the back side of the document pressing area α1. It has a bent structure with the section C) as a boundary. Specifically, the document pressing member 310 includes a first document pressing member 310a (see FIG. 4 and the like) located on the back side and a second document pressing member 310b (see FIG. 4 and the like) located on the front side. ing. The first document pressing member 310a is provided with a document pressing side member 332 in the hinge portion 330, and is opened and closed on the front side by the hinge portion 330 with respect to the image reading apparatus main body 100d. The second document pressing member 310b is vertically bendable around a rotation axis Q2 (see FIG. 4 and the like) along the sub-scanning direction Y with respect to the front end of the first document pressing member 310a. The elastic member 320 is provided on the first document pressing member 310a and the second document pressing member 310b so as to straddle with the central portion or the substantially central portion (here, the central portion C) as the center. The bending angle of the second document pressing member 310b with respect to the first document pressing member 310a may be, for example, about ± 45 °.

  Further, in the present embodiment, the document mounting table 201 has the first side (short side) G1 and the first side (short side) G1 along the direction from the front side to the back side of the document G of the specified size placed on the contact glass 201a. A support portion 340 (see FIG. 4 etc.) that supports a second side (long side) G2 (see FIG. 4 etc.) orthogonal to the side G1 (see FIG. 4 etc.) and a frame body 202 (see FIG. 4) constituting the document placing table 201. 3 and 5) (see FIG. 3 and the like), and an exterior cover member 380 (see FIG. 4 and the like) located outside the supporting portion 340. The outer cover member 380 is made of a resin material such as ABS.

  On the supporting portion 340, characters indicating the size of the document G (here, A3, B4, A4, B5, A5, 2L, B6, A6, and L sizes) are displayed (in FIG. 8 and the like). Reference numeral S1) is provided. Note that, in FIG. 8 and the like, illustration of the size display of the column B is omitted.

  Further, the supporting portion 340 is provided with an arrow (see reference numeral S2 in FIG. 8 and the like) indicating the intersection at the position indicating the intersection of the first side (short side) G1 and the second side (long side) G2. There is.

  More specifically, the supporting section 340 contacts the first side G1 of the document G and contacts one side of the document G along the second side G2, specifically, the other side Y2 in the sub-scanning direction Y (here, document reading start). Side) and a first support portion 341 for restricting movement to the second side G2, and one side in a direction along the first side G1 by contacting the second side G2 of the document G, specifically, the other side in the main scanning direction X. The second support portion 342 for restricting the movement toward X2 (here, the rear side) is provided. Accordingly, the supporting unit 340 can support the document G on the basis of the other side Y2 in the sub-scanning direction Y (here, the document reading start side) and the other side X2 in the main scanning direction X (here, the back side).

  Then, the first support portion 341 and the second support portion 342 are provided with a character S1 indicating the size of the document G, and the first support portion 341 has the first side (short side) G1 and the second side (long side). An arrow S2 indicating the intersection of the side G2 is provided.

  In the present embodiment, the first support portion 341 not only restricts the movement of the document G toward one side in the direction along the second side G2, but also causes the first side of the contact glass 201a to abut against the first side. The second support portion 342 also serves as a support portion that restricts movement toward one side in the direction along the second side orthogonal to the one side, and the second support portion 342 moves to one side in the direction along the first side G1 of the document G. Not only the movement of the contact glass 201a but also the support of the second side of the contact glass 201a in contact with the second side of the contact glass 201a. Further, the supporting portion 340 abuts the third side opposite to the first side of the contact glass 201a to the other side in the direction along the second side, specifically, the one side Y1 in the sub-scanning direction Y (here Then, the third support portion 343 that restricts the movement toward the document reading end side) and the fourth side facing the second side of the contact glass 201a are brought into contact with each other, and the other side in the direction along the first side, specifically, Is provided with a fourth support portion 344 that restricts movement in one side X1 (here, the front side) of the main scanning direction X.

  Further, in the present embodiment, the document pressing device 300 has a sheet-shaped contact member 350 (see FIG. 4 and the like) that comes into contact with the document G placed on the contact glass 201a when the elastic member 320 is pressed against the document G. Is further equipped. The contact member 350 is a member having a predetermined color, which is a white member here.

  The contact member 350 is formed of a resin film material such as polypropylene. The elastic member 320 is provided (specifically, affixed) on the document pressing side of the document pressing member 310, and has the same size as the elastic member 320. The contact member 350 has a uniform thickness (here, 0.1 mm).

  Further, the document pressing member 310, the elastic member 320, and the contact member 350 have the same rectangular shape (rectangular shape) as the document G.

  The pressing member 360 has an original pressing area α1 (see FIG. 4) for pressing the specified size original G and a non-original pressing area α2 outside the original pressing area α1 (see the hatched portion in FIG. 4). are doing. Here, the non-document pressing area α2 is an area inside (front side) of the portion supporting the document pressing member 310 by the hinge portion 330. The document pressing device 300 further includes a restricting member 370. The restricting member 370 partially applies the pressing force F (see FIG. 9 and the like) of the document pressing region α1 to the document G in the non-document pressing region α2 of the pressing member 360. Are regulated. Specifically, the restriction member 370 is an outer region outside the non-original document pressing region α2 of the pressing member 360 and the document region β1 (see the hatched portion in FIG. 4) corresponding to the document pressing region α1 of the document placing table 201. In the overlapping area (overlapping area) γ (see the shaded area in FIG. 8) with β2 (see the shaded area in FIG. 4) (area not involved in the pressing of the original G by the pressing member 360), the original pressing area α1 The pressing force F (see FIG. 9 and the like) on the document G is partially restricted.

  More specifically, the regulation member 370 includes the outer region β2 of the document placing table 201 (here, the support portion 340 located in the outer region β2) and the non-document pressing region α2 of the pressing member 360 (here, the elastic member of the document pressing member 310). The area other than 320).

  FIG. 6 is a schematic cross-sectional view showing a regulating member 370 portion provided in the image reading apparatus 100. FIG. 6A shows a state in which the document G is not pressed at a portion where the pressing force F is not restricted by the restriction member 370. FIG. 6B shows a state in which the original G is pressed by the elastic member 320 via the contact member 350 at a portion where the pressing force F is not restricted by the restriction member 370. FIG. 6C shows a state in which the document G is not pressed at the portion where the pressing force F is restricted by the restriction member 370. FIG. 6D shows a state in which the original G is pressed by the elastic member 320 via the contact member 350 at the portion where the pressing force F is restricted by the restriction member 370.

  In the present embodiment, the restriction member 370 is a support piece that partially supports the non-original document pressing area α2 of the pressing member 360 (specifically, the overlapping area γ of the non-original document pressing area α2 and the outer area β2). There is. Specifically, the regulation member 370 presses the original pressing area α1 against the original G on the back side of the non-original pressing area α2 (specifically, the overlapping area γ) (specifically, the inner side of the central portion C). F is partially regulated.

  Specifically, the regulation member 370 has a predetermined thickness h1 (see FIGS. 6C and 6D), and is a cubic member here. The regulation member 370 has a length d1 (see FIG. 7) in the vertical direction (main scanning direction X in the closed state) of the regulation member 370 of 20 mm, and a length d2 in the lateral direction (sub-scanning direction Y) of the regulation member 370. (See FIG. 7) is 20 mm, and the thickness h1 (h1a, see FIG. 6C) of the regulating member 370 is 6.75 mm in a non-compressed state (a state in which the document G is not pressed).

  Further, the distance D (see FIG. 6A) between the upper surface of the contact glass 201a and the upper surface of the supporting portion 340 is set to 1.4 mm, and the thickness t (FIG. 6A) of the original document (here, a photographic original document) is set. Is 0.2 mm and the total thickness h2 (h2a, see FIGS. 6A and 6C) of the elastic member 320 and the contact member 350 is not compressed (original G). Is 8.3 mm when is not pressed.

  The thickness h1 (h1b, see FIG. 6D) of the regulating member 370 is 6.7 mm (when the document G is pressed by the elastic member 320 via the contact member 350) in a compressed state ( The compression distance is 0.05 mm, and the total thickness h2 of the thickness of the elastic member 320 and the thickness of the contact member 350 is in a compressed state (the original G is pressed by the elastic member 320 via the contact member 350). (State), the portion where the pressing force F is not regulated by the regulating member 370 (thickness h2b, see FIG. 6B) is 7.9 mm (compression distance 0.4 mm), and the pressing force F is regulated by the regulating member 370. In the regulated portion (thickness h2c, see FIG. 6D), it is set to 8.1 mm (compression distance 0.2 mm).

  The restriction member 370 may be provided between the exterior cover member 380 and the document pressing member 310.

  The elastic member 320 is a mat-shaped member, and is made of a foamed resin material such as urethane foam or a porous resin material having a porous shape. Here, F-2 (manufactured by Inoac Corporation) urethane foam is used as the elastic member 320. The elastic member 320 is attached (specifically, affixed) to the document pressing side of the document pressing member 310, is smaller than the size of the document pressing member 310, and is the document G placed on the contact glass 201a. Is about the maximum size (here, A3 size) or larger than the maximum size (here, A3 size). The elastic member 320 has a uniform thickness.

  The regulation member 370 can be formed of a foamed resin material such as urethane foam or a porous resin material having a porous shape. Here, as the regulating member 370, urethane foam of L-32 (manufactured by Rogers Inoac Co., Ltd.) is used.

  In the document pressing device 300 according to the present embodiment, the restricting member 370 is provided at a position facing at least two sides (here, two sides) of the document G placed on the contact glass 201a of the document placing table 201. ing. A plurality of regulating members 370 may be provided along the side of the document G.

  The restriction member 370 is provided so as to include a position where a side of the document G having a predetermined size (here, 2L size) faces. That is, the regulation member 370 is provided at a position facing the side of the document G of at least a predetermined size (here, 2L size). Here, the position facing the side of the document G is a region having a predetermined width m1 (see FIG. 8) outward from the side of the document G. The area on the far side of the width m1 is an area inside the opening / closing axis Q1.

  Next, details of the document pressing device 300 (300A to 300C) according to Examples 1 to 3 of the present embodiment will be described with reference to FIGS. 7 to 15.

(Example 1)
7 to 9 are schematic diagrams for explaining the document pressing device 300 (300A) according to the first embodiment of the present embodiment. FIG. 7 is a schematic bottom view of the document pressing device 300 (300A) according to the first embodiment of the present embodiment as viewed from the bottom. FIG. 8 is a schematic plan view of the original pressing device 300 (300A) shown in FIG. Further, FIG. 9 is a schematic cross-sectional view showing a state where the document pressing device 300 (300A) shown in FIG. 7 is separated from the image reading device main body 100d. 9A shows a state viewed from the A direction shown in FIG. 8, and FIG. 9B shows a state viewed from the B direction shown in FIG.

  In the first embodiment illustrated in FIGS. 7 to 9, the restricting member 370 includes a first restricting member 371 provided on the second side G2 side among positions facing the first side G1 and a position facing the second side G2. Of these, a second regulating member 372 provided on the side of the third side G3 opposite to the first side G1 is provided. Here, the second side G2 side is a position closer to the second side G2 side than the center in the main scanning direction X. This also applies to Examples 2 and 3 described later. The third side G3 side is a position closer to the third side G3 side than the center in the sub scanning direction Y.

  In the example shown in FIGS. 7 to 9, the first restricting member 371 and the second restricting member 372 are provided on the document pressing member 310 so as to be located on the upper surfaces of the first supporting portion 341 and the second supporting portion 342, respectively. However, the first restriction member 371 may be provided at a position outside the first support portion 341 (specifically, so as to be located on the upper surface of the exterior cover member 380), or the second restriction member 371. The restriction member 372 may be provided at a position outside the second support portion 342 (specifically, so as to be located on the upper surface of the exterior cover member 380).

(Example 2)
10 to 12 are schematic views for explaining the document pressing device 300 (300B) according to the second embodiment of the present embodiment. FIG. 10 is a schematic bottom view of the document pressing device 300 (300B) according to the second embodiment of the present embodiment as viewed from the bottom. FIG. 11 is a schematic plan view of a state in which the document pressing device 300 (300B) shown in FIG. 10 is pressing the document G as viewed from above. Further, FIG. 12 is a schematic cross-sectional view showing a state where the document pressing device 300 (300B) shown in FIG. 10 is separated from the image reading device main body 100d. 12A shows a state viewed from the A direction shown in FIG. 11, and FIG. 12B shows a state viewed from the B direction shown in FIG.

  In Example 2 shown in FIGS. 10 to 12, the restricting member 370 includes a third restricting member 373 provided on the second side G2 side of the position facing the third side G3 opposite to the first side G1. A fourth restricting member 374 provided on the first side G1 side among the positions facing the second side G2 is provided. Here, the first side G1 side is a position closer to the first side G1 side than the center in the sub-scanning direction Y.

  In the examples shown in FIGS. 10 to 12, the third restricting member 373 and the fourth restricting member 374 are provided on the document pressing member 310 so as to be located on the upper surfaces of the third supporting portion 343 and the second supporting portion 342, respectively. However, the third restriction member 373 may be provided at a position outside the third support portion 343 (specifically, so as to be located on the upper surface of the exterior cover member 380), or the fourth restriction member 373. The restriction member 374 may be provided at a position outside the second support portion 342 (specifically, so as to be located on the upper surface of the exterior cover member 380).

(Example 3)
13 to 15 are schematic views for explaining the document pressing device 300 (300C) according to Example 3 of the present embodiment. FIG. 13 is a schematic bottom view of the document pressing device 300 (300C) according to the third embodiment of the present embodiment as viewed from the bottom. FIG. 14 is a schematic plan view of the original pressing device 300 (300C) shown in FIG. 15 is a schematic cross-sectional view showing a state in which the document pressing device 300 (300C) shown in FIG. 13 is separated from the image reading device main body 100d, and FIG. 15 is viewed from the direction A shown in FIG. It shows the state.

  In the third embodiment shown in FIGS. 13 to 15, the restricting member 370 faces the first restricting member 371 provided on the second side G2 side of the position facing the first side G1 and the first side G1. The third regulation member 373 provided on the second side G2 side among the positions facing the third side G3 is provided.

  In the example shown in FIGS. 13 to 15, the first restricting member 371 and the third restricting member 373 are provided on the document pressing member 310 so as to be located on the upper surfaces of the first supporting portion 341 and the third supporting portion 343, respectively. However, the first restricting member 371 may be provided at a position outside the first supporting portion 341 (specifically, so as to be located on the upper surface of the exterior cover member 380), or the third restricting member 371. The 373 may be provided at a position outside the third support portion 343 (specifically, so as to be located on the upper surface of the exterior cover member 380).

(Configuration common to Examples 1 to 3)
In Examples 1 to 3 of the present embodiment, the regulation member 370 (the first regulation member 371, the second regulation member 372, the third regulation member 373, and the fourth regulation member 374) has a higher density than the elastic member 320. Alternatively, the physical property value is such that hardness is high.

  More specifically, examples of the physical property value include density and hardness as well as the expansion ratio of the foamed resin material. Here, as the hardness, a value of Asker C (ASKER C) indicating hardness defined in the Japan Rubber Association Standard (SRIS0101) can be exemplified. Further, the expansion ratio can be a ratio of the volume of the expandable material before foaming to the volume of the foamable material before foaming.

  Then, at least one of the hardness and the density of the regulating member 370 (371 to 374) can be made larger than the physical property value of the elastic member 320 corresponding thereto. Alternatively / additionally, the expansion ratio of the elastic member 320 can be made smaller than that of the restriction member 370 (371 to 374). For example, the density of the elastic member 320 can be set to 23 kg / m3 to 27 kg / m3, and the density of the regulating member 370 (371 to 374) can be set to 320 kg / m3.

  In the first to third embodiments, the regulation member 370 (371 to 374) may be attached to at least one of the outer region β2 of the document placing table 201 and the non-document pressing region α2 of the pressing member 360. Further, the regulation member 370 (371 to 374) may be integrally formed with at least one of the outside area β2 of the document placing table and the non-document pressing area α2 of the pressing member 360. Specifically, the restriction member 370 (371 to 374) may be attached to the document pressing member 310 via an adhesive member (for example, an adhesive or a double-sided adhesive sheet), or the document pressing member 310 and the restriction member. The members 370 (371 to 374) may be integrally formed. Alternatively / additionally, the regulating member 370 (371 to 374) is an adhesive member (for example, an adhesive or a double-sided adhesive sheet) to a member that constitutes the outer region β2 of the document placing table 201 such as the support portion 340 and the exterior cover member 380. May be adhered to each other, or the members forming the outer region β2 of the document placing table 201 such as the supporting portion 340 and the exterior cover member 380 and the regulating member 370 (371 to 374) may be integrally formed. .

(About this Embodiment)
As described above, according to the present embodiment, the regulation members 370 (the first regulation member 371, the second regulation member 372, the third regulation member 373, and the fourth regulation member 374) each regulate size (specifically, Is an original pressing area α1 for pressing an original G (for example, an original having glossiness such as a photographic original) of the maximum size among the specified sizes, here A3 size, and a non-original pressing outside the original pressing area α1. In the non-document pressing area α2 of the pressing member 360 having the area α2 (specifically, in the non-document pressing area α2 of the pressing member 360 and the overlapping area γ of the outside area β2 of the document placing table 201), the document of the document pressing area α1 The pressing force F on G can be partially restricted (reduced). Therefore, the pressing force of the pressing member 360 in the original pressing area α1 can be made appropriate in both the portion regulated by the regulating member 370 and the portion not regulated, whereby the original G and the contact glass. Both the spots that may occur in the read image of the original G due to the interference of the light waves in the gap with the 201a and the shadow that may occur in the read image of the original G due to the floating of the original G with respect to the contact glass 201a are effectively prevented. can do. In addition, the original pressing area α1 can be an area for pressing the maximum size (here, A3 size) of the original G of the specified size, and as a result, a predetermined size (here, A3 size) smaller than the maximum size (here, A3 size) can be set. However, the present invention can be applied not only to the document B of B4 size or smaller) but also to the document G of the maximum size (A3 size in this case). These are particularly effective when the original G is an original having gloss (for example, a glossy original) such as a photographic original.

  Further, in the present embodiment, the regulating member 370 is provided outside the area β2 (here, the supporting portion 340) of the document placing table 201 and the non-document pressing area α2 (here, the elastic member 320 of the document pressing member 310) of the pressing member 360. (A region) and is a supporting piece that partially supports the non-document pressing region α2 of the pressing member 360, so that the outside region β2 of the document placing table 201 and the non-document pressing of the pressing member 360 are pressed. It is possible to partially secure a space between the region α2 and the region α2, and thereby to reliably partially regulate the pressing force F of the document pressing region α1 (here, the elastic member 320) of the pressing member 360. You can

  By the way, when the pressing member 360 is configured such that the front side is openably and closably supported by the opening / closing shaft Q1 on the back side as in the present embodiment, the pressing force is applied on the back side of the document pressing area α1. F tends to increase.

  In this respect, in the present embodiment, even if the pressing member 360 is configured such that the front side can be opened / closed and is supported by the opening / closing shaft Q1 on the back side, the restriction member 370 does not push the non-document pressing area α2 (specifically, Specifically, by partially restricting the pressing force F of the original pressing area α1 on the original G on the inner side of the overlapping area γ) of the non-original pressing area α2 and the outer area β2, The pressing force F, which tends to increase, can be reliably regulated (weakened) on the inner side, and thus both spots and shadows can be effectively prevented.

  Further, in the case where the pressing member 360 has a two-fold structure in which the pressing member 360 is foldable with the central part or substantially central part (here, central part C) of the document pressing region α1 as a boundary, as in the present embodiment. In addition, the pressing force F in the document pressing area α1 is likely to be larger on the back side than on the front side.

  In this respect, in the present embodiment, the pressing member 360 has a two-fold structure in which the pressing member 360 can be bent at the center or substantially the center (here, the center C) of the document pressing area α1 as a boundary. The restricting member 370 partially restricts the pressing force F of the document pressing area α1 on the document G on the inner side of the non-original document pressing area α2 (specifically, the overlapping area γ), so that it is deeper than the front side. The pressing force F in the document pressing area α1 that tends to increase on the side can be reliably regulated (weakened) on the back side, and both spots and shadows can be effectively prevented.

  Further, in the pressing member 360, when the opening / closing axis Q1 is movable in the vertical direction Z as in the present embodiment, the pressing force F in the document pressing area α1 is on the back side rather than the front side. Easy to grow.

  In this regard, in the present embodiment, in the pressing member 360, even if the opening / closing axis Q1 is movable in the vertical direction Z, the regulating member 370 has the non-document pressing area α2 (specifically, the overlapping area γ). By partially restricting the pressing force F on the document G in the document pressing area α1 on the back side, the pressing force F on the document pressing area α1 that tends to be larger on the back side than on the front side is surely set on the back side. It can be regulated (weakened), and thus both spots and shadows can be effectively prevented.

  Further, in the present embodiment, since the regulating member 370 is provided at a position facing at least two sides of the document G placed on the contact glass 201a, the pressing force of the pressing member 360 on the document pressing area α1 is set. F can be partially restricted on the back side of at least two sides of the document G, whereby the pressing force F on the document pressing area α1 (here, the elastic member 320) of the pressing member 360 is partially restricted. Can be done stably.

  Specifically, in the first embodiment, the first restricting member 371 is provided on the second side G2 side of the positions facing the first side G1, and the third restricting member 372 is the third position of the position facing the second side G2. Since it is provided on the side of the side G3, the pressing force F on the document pressing area α1 (here, the elastic member 320) of the pressing member 360 is the second of the positions facing the first side G1 by the first restricting member 371. Not only can it be partially regulated on the side of the side G2, but it can also be partially regulated on the side of the third side G3 of the positions facing the second side G2 by the second regulating member 372, and that much of the pressing member 360. Partial regulation of the pressing force F in the document pressing area α1 can be stably performed.

  In the second embodiment, the third restricting member 373 is provided on the second side G2 side of the positions facing the third side G3, and the fourth restricting member 374 is the first side of the positions facing the second side G2. Since it is provided on the G1 side, the pressing force F on the document pressing area α1 (here, the elastic member 320) of the pressing member 360 is the first side of the positions facing the second side G2 by the fourth restricting member 374. Not only can it be partially restricted on the G1 side, but it can also be partially restricted on the second side G2 side of the position facing the third side G3 by the third restricting member 373, and that is the original of the pressing member 360. The partial restriction of the pressing force F in the pressing area α1 can be stably performed.

  In the third embodiment, the first restricting member 371 is provided on the second side G2 side of the position facing the first side G1, and the third restricting member 373 is the second side of the position facing the third side G3. Since it is provided on the G2 side, the pressing force F on the document pressing area α1 (here, the elastic member 320) of the pressing member 360 faces the first side G1 by the first restricting member 371. Not only can it be partially regulated on the G2 side, but it can be partially regulated on the second side G2 side of the position facing the third side G3 by the third regulation member 373. The partial restriction of the pressing force F in the pressing area α1 can be stably performed.

  By the way, the document G (in particular, a document having a glossiness such as a photographic document) placed on the contact glass 201a of the document placing table 201 is generally smaller than the maximum size (here, A3 size) of the specified sizes. Frequently small size originals.

  In this regard, in the present embodiment, the regulating member 370 is provided so as to include the position facing the side of the document of a predetermined size (for example, 2L size), so that the document pressing region α1 (elasticity in this case) of the pressing member 360 is reduced. The pressing force F on the member 320) can be partially restricted by the restriction member 370 on the side of the side of the document G of a predetermined size (for example, 2L size), and thus the document pressing area α1 of the pressing member 360 can be controlled. Partial regulation of the pressing force F in the area for pressing the document G of a predetermined size (for example, 2 L size) can be surely performed.

  Here, the regulating member is provided in at least one of the outer region β2 (here, the supporting portion 340) of the document placing table 201 and the non-document pressing region α2 (here, the region other than the elastic member 320 of the document pressing member 310) of the pressing member 360. 370 can be provided. That is, when the regulating member 370 is provided only in the non-original document pressing area α2 of the pressing member 360, when the regulating member 370 is provided only in the outer area β2 of the document placing table 201, and when the outer area β2 and the pressing member of the document placing table 201 are provided. The case where the regulating member 370 is provided in both of the non-document pressing area α2 of 360 can be exemplified. When the restricting member 370 is provided only in the non-document pressing area α2 of the pressing member 360, when the pressing member 360 is closed, the restricting member 370 provided in the non-document pressing area α2 is provided outside the document table 201. It can be brought into contact with β2. When the restricting member 370 is provided only in the outer area β2 of the document placing table 201, when the pressing member 360 is closed, the restricting member 370 provided in the outer area β2 becomes the non-original pressing area α2 of the pressing member 360. Can be brought into contact. When the regulating member 370 is provided in both the non-document pressing area α2 of the pressing member 360 and the outer area β2 of the document placing table 201, it is provided in the non-document pressing area α2 when the pressing member 360 is closed. The regulating member 370 and the regulating member 370 provided in the outer region β2 can be brought into contact with each other.

  Here, the regulation member 370 is at least in the outside area β2 (here, the supporting portion 340) of the document placing table 201 and the non-document pressing area α2 (here, the area other than the elastic member 320 of the document pressing member 310) of the pressing member 360. When it is provided on the outer side area β2 of the document placing table 201, the regulating member 370 becomes an obstacle when an operator such as a user places the document G on the contact glass 201a of the document placing table 201. However, it causes inconvenience such as peeling or damage.

  In this respect, as in the present embodiment, the restricting member 370 causes the outside area β2 (here, the supporting portion 340) of the original document table 201 and the non-original pressing area α2 of the pressing member 360 (here, the elastic member of the original pressing member 310). When the original G is placed on the contact glass 201a of the original placing table by an operator such as a user, the regulating member is provided only in the non-original pressing area α2 of the pressing member 360 of the area other than 320). It is possible to suppress the occurrence of inconveniences such as the 370 being an obstacle, peeling off, or being damaged.

  Further, in the present embodiment, since the regulating member 370 is made of an elastic material, damage to the mating side of the regulating member 370 (here, the support portion 340) when the pressing member 360 is closed. Can be suppressed.

  By the way, when the density of the regulating member 370 is the same as or smaller than the density of the elastic member 320, or the hardness thereof is the same as or smaller than the hardness of the elastic member 320, the original pressing area α1 of the elastic member 320. It becomes difficult to partially regulate the pressing force F at.

  In this respect, as in the present embodiment, the restriction member 370 has a physical property value that has a higher density or hardness than the elastic member 320, so that the pressing force of the elastic member 320 in the original pressing area α1 is increased. Partial regulation of F can be surely performed.

  In the present embodiment, the regulating member 370 may be a protrusion-shaped member having hardness (for example, a hard resin member). In this case, the regulating member 370 can be formed of a member similar to the exterior cover member 380 and the document pressing member 310, for example, a resin material such as ABS.

  FIG. 16 is a schematic diagram showing a state in which the regulating member 370 in the document pressing device 300 (300A to 300C) is a protrusion-shaped member having hardness and the pressing member 360 is closed. FIG. 16A shows an example in which the regulation member 370 is provided in the non-document pressing area α2 of the document pressing member 310. FIG. 16B shows an example in which the regulation member 370 is provided on the support portion 340 in the outer region β2 of the document placing table 201. 16C shows an example in which the regulating member 370 is provided on both the non-document pressing area α2 of the document pressing member 310 and the support portion 340 in the outer area β2 of the document mounting table 201.

  As shown in FIGS. 16 (a) to 16 (c), since the regulation member 370 is a protrusion-shaped member having hardness, the regulation member 370 has a size as small as possible, Partial regulation of the pressing force F on the document pressing area α1 of the document pressing member 310 can be reliably performed. Further, the regulation member 370 and at least one of the non-document pressing area α2 of the document pressing member 310 and the supporting portion 340 in the outer area β2 of the document placing table 201 can be easily integrally formed. In the example shown in FIG. 16, the shape of the tip of the regulating member 370 is a planar shape, but a space is secured between the outer region β2 of the document placing table 201 and the non-document pressing region α2 of the document pressing member 310. It may have any shape as long as it can be formed, and may have, for example, a convex curved surface shape.

  In the present embodiment, the centimeter type configuration has been described, but of course, the inch type configuration may be used.

[Evaluation of spots and shadows]
Next, in Examples 1 to 3 of the present embodiment, spots that may occur in the read image of the original G due to interference of light waves in the gap between the original G and the contact glass 201a, and the original G on the contact glass 201a. Since the generation state of a shadow (fogging) that may occur in the read image of the document G due to the floating of the paper is examined, it will be described below together with a comparative example in which the regulating member 370 is not provided.

  17A and 17B show spots that may occur in the read image of the document G due to interference of light waves in the gap between the document G and the contact glass 201a, and the floating of the document G with respect to the contact glass 201a causes the read image of the document G. It is a chart showing the evaluation result of the generation state of the obtained shadow (fog). In FIG. 17, “⊚” indicates that a sufficiently acceptable read image was obtained, “◯” indicates that an acceptable read image was obtained, and “x” indicates This indicates that the read image is unacceptable.

  The spot and shadow (fogging) evaluations in Examples 1 to 3 and Comparative Example of the present embodiment are based on images read in a photographic mode using a white photographic paper having a thickness of 0.2 mm as the original G. It was carried out by confirming the printed image printed on.

  As shown in FIG. 17, in the comparative example, both the spots and the shadows (fogs) resulted in unacceptable read images, whereas in Examples 1 to 3 of the present embodiment, the spots and the shadows (fogs) In both cases, the read image was sufficiently or acceptable.

100 image reading device 201 original placing table 201a contact glass (an example of a transparent plate)
300 document pressing device 310 document pressing member 320 elastic member 330 hinge part 340 support part 341 first support part 342 second support part 350 contact member 360 pressing member 370 restriction member 371 first restriction member 372 second restriction member 373 third restriction Member 374 Fourth regulating member 400 Image forming apparatus C Central portion F Pressing force G Original document G1 First side G2 Second side G3 Third side Q1 Opening / closing axis Q2 Rotating axis S1 Character S2 Arrow X Main scanning direction Y Sub-scanning direction Z Vertical direction α1 Original pressing area α2 Non original pressing area β1 Original area β2 Outside area γ Overlap area

Claims (8)

An image reading apparatus including an image reading unit including an original placing table having a transparent member on which an original is placed, and an original pressing device including an original pressing member for pressing the original placed on the transparent member. And
The image reading unit is provided with a rotation support unit that supports the document pressing device so as to be openable and closable,
The image reading unit is provided with a non-document placement area outside the transparent member ,
The document pressing device is provided with a contact piece that partially contacts the non-document placement region when the document pressing device is closed,
The image reading apparatus, wherein the contact piece is provided within a width of the document pressing member in a direction orthogonal to a rotation axis direction of the rotation support portion. The image reading device according to claim 1,
The image reading apparatus is characterized in that a plurality of the contact pieces are provided in an area corresponding to the non-document placement area on one side with the transparent member in between in the rotation axis direction. The image reading device according to claim 1 or 2, wherein
The image reading apparatus is characterized in that the contact pieces are respectively provided in regions corresponding to the non-document placement regions on one side and the other side with the transparent member in between in the rotation axis direction. The image reading device according to any one of claims 1 to 3 ,
The contact piece that comes into contact with the non-original document placement area is provided closer to the rotation support portion than the center of the document pressing member in the direction orthogonal to the rotation axis direction of the rotation support portion. Characteristic image reading device. The image reading device according to any one of claims 1 to 4 ,
The sheet presser, in the perpendicular direction, is composed of the round first and document pressing device provided to the moving support part side, a second sheet presser, which is freely bent with respect to the first sheet presser ,
The image reading device, wherein the contact piece is provided in the first document pressing device. The image reading device according to any one of claims 1 to 5 ,
The image reading device, wherein the rotation support portion is supported so as to be vertically movable with respect to the image reading portion. The image reading device according to any one of claims 1 to 6 ,
An elastic member provided on the document pressing device for pressing the document;
The image reading apparatus, wherein the contact piece has a protrusion shape having hardness. An image forming apparatus comprising the image reading device according to any one of claims 1 to 7 .

Images