JP2011130233A - Image reading apparatus and image forming apparatus with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus capable of quickly detecting a tilt of a document carrier, and to provide an image forming apparatus with the same. <P>SOLUTION: Decision charts 77a and 77b are attached to both back and forth ends of a device body in a lower surface part 73a of a carrier guide 73 provided to a document carrier device 27 of the image reading apparatus 6. Upon detecting the tilt, first and second carriage 68 and 69 scan along a reading line Ls while being stopped under the decision charts 77a and 77b, and detect the tilt of the document carrier device 27 by detecting a displacement with a CCD sensor 67 between a straight line L1 connecting an intersection point A1 of the decision chart 77a and an intersection point A2 of the decision chart 77b, and a reading line Ls. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus used for a digital copying machine, an image scanner, and the like, for scanning and reading an original, and an image forming apparatus including the image reading apparatus. It relates to the device.

  2. Description of the Related Art Conventionally, in an image reading apparatus mounted on a multifunction machine using an electrophotographic process, a document is conveyed so that a sheet-like document is sequentially sent to a document placing table and discharged from the document placing table after the reading is completed. Some have an apparatus (Automatic Document Feeder). In such an image reading apparatus, a sheet-through method in which a document is automatically conveyed and read by a document conveying device while the document press is closed, and the document press is opened and closed each time reading is performed on a document placement table (contact glass). Two types of reading methods are possible: a document fixing method in which the original is replaced one by one and the optical system (scanning means) is moved to read the original. In the former sheet-through method, the optical system in the image reading apparatus is scanned and moved while being held at a predetermined image reading position. On the other hand, in the latter document fixing method, A reading operation is performed while the optical system scans and moves.

  In an image reading apparatus having such a sheet-through method, when a document is conveyed obliquely, the read image is also inclined. Therefore, for example, in Patent Document 1, the moving unit (scanning unit) is operated in a state where the document feeding unit (document feeding unit) does not feed the document, and the document feeding unit is fixedly read by the reading unit. By creating information about the tilt of the document feeder using the fixed reading results, the accuracy of measuring the tilt adjustment amount of the automatic document feeder is remarkably increased, and the adjustment of the mounting angle can be performed quickly and easily with high accuracy and low cost. A method of completing is disclosed.

  In Patent Document 1, the scanning unit is moved, and a white platen roller, a white sheet, and a scraping sheet arranged on the lower surface of the document conveying unit are read in this order. As a result, the read image includes a white belt (platen Roller), black belt (gap between platen roller and white sheet), white belt (white sheet), black belt (shadow on scraped sheet edge), and white belt (scraping sheet) appear in order, so The position (distance) of the two black belt images is measured on the front side (front side) and the back side (rear side) of the image, and the inclination of the document conveying means is adjusted so that the positions coincide with each other. .

JP 2008-61058 A

  However, in the method of Patent Document 1, in order to detect the inclination of the document conveying unit, it is necessary to read the lower surface of the document conveying unit while moving the scanning unit. For this reason, it is necessary to wait while the scanning unit moves while reading an image, and it may take time to detect the tilt. Further, since the inclination of the document conveying means cannot be corrected (adjusted) unless such detection is completed, it may take time to adjust the inclination accordingly.

  SUMMARY An advantage of some aspects of the invention is that it provides an image reading apparatus capable of quickly detecting the inclination of an original conveying unit and an image forming apparatus including the image reading apparatus.

  In order to achieve the above object, the present invention provides a contact glass disposed on the upper surface of the apparatus main body, a document conveying means that can be opened and closed upward with respect to the contact glass, and conveys a document to the upper surface of the contact glass; The document conveying means is disposed along a direction perpendicular to the document conveying direction, is opposed to the upper surface of the contact glass at a predetermined interval, and guides the document, and below the contact glass An image reading apparatus comprising: an image reading unit disposed; and a scanning unit that irradiates a document with light from below the contact glass and guides reflected light to the image reading unit, wherein the scanning unit is the contact The image reading unit reads the lower surface portion while stopping at a position facing the lower surface portion of the guide member with the glass interposed therebetween, thereby detecting the inclination of the document conveying means. It is characterized in that.

  The present invention is also characterized in that detection patterns are provided at both ends of the lower surface portion in the vertical direction, and the inclination is detected by the image reading unit reading the detection pattern.

  In the invention, it is preferable that the detection pattern is arranged along the transport direction, and has an intersection at the center of the detection pattern in the transport direction, and the lower surface portion toward the upstream side from the intersection. The first end portion side in the vertical direction is widened, and the second end portion side opposite to the first end portion side is widened toward the downstream side. It is characterized by.

  In the invention, it is preferable that the detection pattern is attached to the lower surface portion.

  Further, the invention is characterized in that the detection patterns are arranged on both outer sides in the vertical direction with respect to the image reading region.

  In addition, the present invention is characterized in that a display means for displaying the result of detection of the tilt by the image reading unit is provided.

  Further, the present invention is arranged at both ends in the transport direction on the one end side in the vertical direction of the document transport means, supports the document transport means so as to be openable and closable, and adjusts the positions of the both ends along the vertical direction. A possible position adjusting means is provided.

  According to the present invention, the position adjusting means includes a hinge member, a position adjusting member to which the document conveying means is fixed via the hinge member, and an upper surface of the apparatus main body with the position adjusting member interposed therebetween. A first fixing member that slidably holds the position adjusting member along the vertical direction with the upper surface of the apparatus main body and can be fixed to the upper surface of the apparatus main body at a predetermined position; and A position adjusting screw for connecting the position adjusting member to the fixing member so as to be movable along the vertical direction is provided.

  Further, the present invention is fixed to the upper surface of the apparatus main body and disposed below the first fixing member with the position adjusting member interposed therebetween, and the vertical adjustment member sandwiching the position adjusting member with the first fixing member. A second fixing member is provided that can be slidably moved in a direction and can position the first fixing member with respect to the upper surface of the apparatus main body.

  Further, the present invention is characterized in that the inclination can be adjusted by the position adjusting means based on the detection result of the inclination by the image reading unit.

  The present invention is also an image forming apparatus on which the image reading apparatus is mounted.

  According to the first configuration of the present invention, the image reading unit reads the lower surface while the scanning unit is stopped at a position facing the lower surface of the guide member with the contact glass interposed therebetween. Since the inclination is detected, it is not necessary to detect the inclination of the document conveying means while moving the scanning means, and it is possible to quickly detect the inclination of the document conveying means. Further, it is possible to detect the inclination of the document conveying means without conveying the document.

  According to the second configuration of the present invention, in the image reading apparatus of the first configuration, the detection patterns are provided at both ends in the vertical direction on the lower surface, and the image reading unit tilts by reading the detection patterns. By detecting this, it is possible to more reliably detect the inclination of the document conveying means.

  According to the third configuration of the present invention, in the image reading apparatus having the second configuration, the detection pattern is arranged along the transport direction, and at the center of the detection pattern in the transport direction. A second end portion having an intersection and having a width that is wider toward the first end side in the vertical direction of the lower surface portion toward the upstream side from the intersection point, and opposite to the first end side toward the downstream side By forming the side so as to be wide on the side, it is possible to easily and reliably detect the tilt direction and the tilt amount of the document conveying means.

  Further, according to the fourth configuration of the present invention, in the image reading apparatus having the second or third configuration, the detection pattern can be easily formed on the lower surface by attaching the detection pattern to the lower surface. In addition, the detection pattern can be removed or replaced as necessary, which is effective.

  Further, according to the fifth configuration of the present invention, in the image reading apparatus having any one of the second to fourth configurations, the detection patterns are arranged on both outer sides in the vertical direction with respect to the image reading area. It is possible to detect the inclination of the document conveying means without affecting the image reading.

  According to the sixth configuration of the present invention, in the image reading apparatus having any one of the first to fifth configurations, the display unit that displays the detection result of the tilt by the image reading unit is provided. The inclination of the document conveying means can be adjusted while checking the inclination with the means, and the inclination can be adjusted easily and efficiently, so that the detection of the inclination becomes more effective.

  According to the seventh configuration of the invention, in the image reading apparatus having any one of the first to sixth configurations, the document conveying means is provided at both ends in the conveying direction on the one end side in the vertical direction of the document conveying means. By providing position adjustment means that can be opened and closed and the positions of both ends can be adjusted along the vertical direction, the tilt can be adjusted by simply changing the positions of both ends in the vertical direction. In addition, the inclination of the document conveying means can be adjusted efficiently.

  According to the eighth configuration of the invention, in the image reading apparatus having the seventh configuration, the position adjustment means includes a hinge member and a position adjustment member to which the document conveying means is fixed via the hinge member. The position adjusting member is disposed above the upper surface of the apparatus main body, and can be slidably held along the vertical direction with the upper surface of the apparatus main body and fixed to the upper surface of the apparatus main body at a predetermined position. By providing a first fixing member and a position adjusting screw for connecting the position adjusting member to the first fixing member so as to be movable along the vertical direction, both end portions can be obtained simply by rotating the position adjusting screw. Therefore, the inclination of the document conveying means can be adjusted more easily and efficiently.

  According to the ninth configuration of the present invention, in the image reading apparatus having the seventh or eighth configuration, the image reading apparatus is fixed to the upper surface of the apparatus main body and disposed below the first fixing member with the position adjustment member interposed therebetween. And a second fixing member capable of positioning the first fixing member with respect to the upper surface of the apparatus main body while sandwiching the position adjusting member with the first fixing member so as to be slidable in the vertical direction. Thus, the accuracy of adjusting the inclination of the document conveying means can be increased.

  According to the tenth configuration of the present invention, in the image reading apparatus having any one of the seventh to ninth configurations, the tilt can be adjusted by the position adjusting unit based on the tilt detection result by the image reading unit. By doing so, it is possible to quickly perform from the detection of the inclination of the document conveying means to the adjustment, which is more efficient and effective.

  Further, according to the eleventh configuration of the present invention, an image defect caused by the inclination of the document conveying means is obtained by employing the image forming apparatus on which the image reading apparatus having any one of the first to tenth configurations is mounted. It is possible to perform image formation in which the image is prevented.

1 is a side sectional view showing an overall configuration of an image forming apparatus including an image reading apparatus according to an embodiment of the present invention. Side surface sectional view showing the internal structure around the document conveying device used in the image reading apparatus according to the present embodiment Side surface sectional view showing the internal structure of the image reading apparatus according to the present embodiment Partial expanded sectional view which shows the periphery of the conveyance guide of FIG. 2, and the glass for automatic reading View of the transport guide as viewed from the direction A in FIG. FIG. 6A is a diagram schematically showing the relationship between the arrangement of the document conveying device used in the image reading apparatus according to the present embodiment and the CCD output value, and FIG. 6A shows a state where the document conveying device is not tilted. 6B is a diagram illustrating an example of a state in which the document conveying device is tilted, and FIG. 6C is a diagram illustrating another example of a state in which the document conveying device is tilted. FIG. 7A is a diagram schematically illustrating the relationship between the arrangement of the document conveying device used in the image reading apparatus according to the present embodiment and the scanned image, and FIG. 7A is a diagram illustrating the document, and FIG. ) Is a diagram showing a read image when the document conveying device is tilted to the state of FIG. 6B, and FIG. 7C is a diagram of the document conveying device being tilted to the state of FIG. 6C. Showing the scanned image FIG. 3 is a schematic perspective view showing the periphery of the position adjustment mechanism in the image forming apparatus including the image reading apparatus according to the present embodiment from the back side. Schematic perspective view showing the position adjustment mechanism before assembly from the back side Schematic perspective view showing the position adjustment mechanism before assembly from the front side FIGS. 11A and 11B are views showing a state in which a position adjusting member used in the position adjusting mechanism has moved to the front side, FIG. 11A being a perspective view, and FIG. 11B being BB ′ in FIG. FIG. 11 (c) is a cross-sectional view taken along the arrow CC ′ of FIG. 11 (b). It is a figure which shows the state which the position adjustment member used for a position adjustment mechanism moved to the back side, Comprising: Fig.12 (a) is a perspective view, FIG.12 (b) is DD 'of Fig.12 (a). FIG. 12 (c) is a cross-sectional view taken along the arrow EE ′ of FIG. 12 (b). FIGS. 13A and 13B are diagrams illustrating a state in which the position adjusting member is fixed to the apparatus main body, FIG. 13A is a schematic perspective view, and FIG. 13B is a periphery of the first fixing screw in FIG. Partial enlarged perspective view showing

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus including an image reading apparatus according to an embodiment of the present invention. In FIG. 1, in the image forming apparatus 100 (here, a digital multi-function peripheral is shown as an example), when performing a copying operation, image data of a document is read and converted into an image signal by an image reading apparatus 6 described later. On the other hand, in the image forming unit 3 in the MFP main body 2, the photosensitive drum 5 rotating in the direction A in the figure is uniformly charged by the charging unit 4, and is based on the document image data read by the image reading device 6. An electrostatic latent image is formed on the photosensitive drum 5 by a laser beam from an exposure unit (laser scanning unit or the like) 7, and a developer (hereinafter referred to as toner) is attached to the electrostatic latent image by the developing unit 8. An image is formed. The toner is supplied to the developing unit 8 from the toner container 9.

  The sheet is conveyed from the sheet feeding mechanism 10 to the image forming unit 3 via the sheet conveying path 11 and the registration roller pair 12 toward the photosensitive drum 5 on which the toner image is formed as described above. 3, the toner image on the surface of the photosensitive drum 5 is transferred to the sheet by the transfer roller 13 (image transfer unit). The sheet onto which the toner image has been transferred is separated from the photosensitive drum 5 and conveyed to a fixing unit 14 having a fixing roller pair 14a to fix the toner image. The paper that has passed through the fixing unit 14 is sent to a paper conveyance path 15 that branches in a plurality of directions, and is fed by a path switching mechanism 21, 22 having a plurality of path switching guides provided at branch points of the paper conveyance path 15. The transport directions are sorted, and the sheets are discharged as they are (or after being sent to the sheet transport path 16 and double-sided copying) to the sheet discharge section including the first discharge tray 17a and the second discharge tray 17b.

  Although not shown, a static elimination device that removes residual charges on the surface of the photosensitive drum 5 is provided on the downstream side of the cleaning device 18. Further, the paper feed mechanism 10 is detachably attached to the multifunction machine main body 2 and includes a plurality of paper feed cassettes 10a and 10b for storing paper, and a stack bypass (manual feed tray) 10c provided above the paper feed cassettes 10a and 10b. These are connected to the image forming unit 3 including the photosensitive drum 5 and the developing unit 8 by the paper transport path 11.

  An image reading device 6 is disposed on the upper portion of the apparatus main body, and a platen (document pressing member) that holds and holds a document placed on the contact glass 25 (see FIG. 2) of the image reading device 6 on the upper surface of the apparatus main body. ) 24 (see FIG. 1) is provided so as to be openable and closable, and a document conveying device 27 is provided on the platen 24.

  Specifically, the sheet conveyance path 15 first branches into a left and right fork on the downstream side of the fixing roller pair 14a, and one path (a path branching rightward in FIG. 1) communicates with the first discharge tray 17a. It is configured as follows. The other path (the path that branches in the left direction in FIG. 1) is bifurcated via the conveying roller pair 19, and the other path (the path that branches in the left direction in FIG. 1) is the second discharge tray 17b. It is comprised so that it may communicate with. On the other hand, the other path (the path that branches downward in FIG. 1) is configured to communicate with the sheet conveyance path 16.

  FIG. 2 is a side sectional view showing the internal structure around the document conveying device used in the image reading apparatus according to the first embodiment of the present invention. The document transport device 27 includes a document feed tray 29 provided with a document guide 29 a for aligning and stacking a plurality of documents, and a reversing tray 30 provided below the document feed tray 29. Each member of the paper tray 29 and the reverse tray 30 is attached to the frame of the document conveying device 27. Further, a cover member 31 is supported so as to be openable and closable with one end (lower left in the figure) as a rotation fulcrum with respect to the frame of the document conveying device 27, and a document discharge tray 32 is disposed on the side of the cover member 31. It is formed directly on a part of the upper surface. A document transport path d from the document feed tray 29 to the document discharge tray 32 is formed in the cover member 31. By opening the cover member 31, the document transport path d is opened, and jamming can be performed. ing.

  In the cover member 31, a pickup roller 33, a paper feed belt 34 and a separation roller 35, a registration roller pair 36, a conveyance roller pair 37, 38, 39, and 40, a CIS roller 41, a reverse roller along the document conveyance path d. A document conveying member including a pair 42, a discharge roller pair 43, and the like is provided. The paper feed belt 34 is wound around a driving roller 44a and a driven roller 44b, and a separation roller 35 is in contact with the roller at a predetermined pressure from below. The separation roller 35 has a built-in torque limiter, which rotates in the opposite direction to the paper feed belt 34 only when the rotational load is lower than a predetermined torque, and is driven to rotate with the paper feed belt 34 when the rotational load exceeds a predetermined torque. It is supposed to be. Above the pickup roller 33, an upper surface detection sensor 50 for detecting the upper surface position of the document is disposed.

  The contact glass 25 includes an automatic reading glass 25a and a manually placed original glass 25b. A white reference plate for shading correction disposed opposite to the automatic reading glass 25a, and a white reference plate above the white reference plate. A document pressing portion (none of which is shown) for pressing the reference plate toward the automatic reading glass 25a is provided. The document conveyance path d is curved so as to be reversed between the registration roller pair 36 and the automatic reading glass 25a. A plurality of paper detection sensors including a paper feed sensor S1 and a discharge sensor S2 for detecting the presence / absence or passage of a document are provided at appropriate positions on the document conveyance path d.

  Next, a sheet-through type document conveying operation using the document conveying device 27 will be described. In the sheet-through method, after a plurality of documents are set on the document feed tray 29 with the image surface facing upward, the copy start button on the operation panel (display unit) 75 (see FIG. 1) of the image forming apparatus 100 is turned on. Then, the lift plate 45 lifted by the lifting mechanism (not shown) pushes up the pickup roller 33 through the document, and the weight of the frame (not shown) including the pickup roller 33 is added to the lift plate 45. As a result, the upper surface of the document is pressed against the pickup roller 33 with a predetermined pressure (feed pressure).

  Here, the pickup roller 33, the drive roller 44a, the driven roller 44b, and the paper feed belt 34 are arranged in a frame not shown. The pickup roller 33 is connected to a drive roller 44a by a gear (not shown). When the drive roller 44a is rotated by a roller drive motor (not shown), the pickup roller 33 is stretched by the drive roller 44a and the driven roller 44b. The paper belt 34 is driven to rotate, and the pickup roller 33 is also driven to rotate.

  The document set on the document feed tray 29 is usually fed to the nip portion between the feed belt 34 and the separation roller 35 by a pickup roller 33. Only the uppermost one of the plurality of documents is separated by the separation roller 35 and conveyed toward the registration roller pair 36. At that time, after the leading edge of the document is detected by the sheet feed sensor S1, the document is conveyed by a predetermined distance, and then the rotation drive of the pickup roller 33 and the sheet feed belt 34 is stopped by stopping the operation of the roller drive motor. Paper feeding ends. The document that has been primarily fed is stopped in a state where the leading end of the document is bent at the nip portion of the registration roller pair 36.

  Secondary feeding is started after a predetermined time has elapsed since the completion of primary feeding. That is, the registration roller pair 36 is rotationally driven by the operation of a secondary paper feed drive motor (not shown). The original is conveyed by the registration roller pair 36, the conveyance roller pairs 37 to 39, and the CIS roller 41 through the automatic reading glass 25a toward the discharge roller pair 43, and finally the original is discharged by the discharge roller pair 43. It is discharged onto the tray 32. At this time, the completion of image reading of one original is detected by detecting passage of the rear end of the original by the discharge sensor S2.

  Here, the discharge sensor S2 has a count function for counting the number of documents every time the document conveyance is completed. If the paper feed sensor S1 detects a subsequent document, the second and subsequent document conveyance is performed as described above. Will continue as well. When the original passes through the automatic reading glass 25a, the original is conveyed while being lightly pressed toward the automatic reading glass 25a from above by contacting the conveyance guide 73, and the image of the original is automatically read glass. The image is read by the image reading device 6 (see FIG. 1) through 25a. Details of the conveyance guide 73 will be described later.

  When reading a double-sided document, a contact image sensor 51 provided opposite to the CIS roller 41 reads an image on the back side of the document, and an automatic reading glass 25a reads an image on the surface of the document. After reading the image on the surface of the document with the reading glass 25a, the document is distributed to the reversing tray 30 by the branching claws 47a, 47b and 47c, the reversing roller pair 42 is reversed, and again with the back side of the document facing up. There is a two-stage reading method in which the image is conveyed to the upstream side of the registration roller pair 36 and the image on the back side of the document is read by the automatic reading glass 25a.

  Reading by the contact image sensor 51 can shorten the reading time, but is inferior in image quality as compared with reading by the automatic reading glass 25a. For this reason, a one-step reading method using the contact image sensor 51 is used for text originals, and a two-step reading method using the reversing tray 30 is used when high-quality and high-definition reading is required for photo originals. It is preferable.

  When the two-stage reading method is used, when the original after reading is sequentially discharged to the original discharge tray 32 as it is, the discharged original is stacked with the reverse side of the state set on the original feed tray 29. It will be. Therefore, after the image on the back side of the document is read by the automatic reading glass 25 a, the branching claws 47 a to 47 c are swung to introduce the document again onto the reverse tray 30, and the pair of conveyance rollers 40 and the discharge roller pair 43 are used. The document is discharged to the document discharge tray 32. As a result, the front and back of each document are reversed again before being discharged, so that they can be stacked on the document discharge tray 32 while maintaining the state of being set on the document feed tray 29.

  Next, the configuration of the image reading device 6 for reading an image of a document as an electric signal will be described. FIG. 3 is a side sectional view showing the internal structure of the image reading apparatus according to this embodiment. In the frame 6a of the image reading device 6, a lamp (light source) 61 that irradiates light toward the image surface of the document, and a reflecting plate 62 for efficiently applying light from the lamp 61 to the image surface of the document. The first mirror 63 that directly receives and reflects the original reflected light, the second mirror 64 that receives and reflects the reflected light from the first mirror 63, and the reflected light that is received from the second mirror 64 and reflected. A third mirror 65 is disposed.

  Further, a lens barrel 66 holding a lens group (not shown) for introducing and collecting the reflected light from the third mirror 65, and the original reflected light collected by the lens group of the lens barrel 66 are received. A line-type CCD (photoelectric conversion member) sensor (image reading unit) 67 including a photoelectric conversion element that converts an electric signal is disposed on the base plate 70. The optical path of the original reflected light is indicated by a one-dot chain line.

  Here, the lamp 61, the reflector 62 and the first mirror 63 are integrally fixed on the first carriage 68, and the second mirror 64 and the third mirror 65 are integrally fixed on the second carriage 69. ing. These first and second carriages 68 and 69 constitute scanning means and are reciprocally movable in cooperation with each other although they are independent of each other.

  That is, when the original image reading operation is performed by the sheet through method, the first carriage 68 is moved and held immediately below the first image reading region (image reading region) R1 of the automatic reading glass 25a. At the same time, the second carriage 69 is held at a predetermined position. On the other hand, in the original fixing method, the first carriage 68 and the second carriage 69 maintain the optical path length of the original reflected light with respect to each other for a manually placed original. The glass 25b is reciprocated (scanned) below the second image reading region R2. The first carriage 68 and the second carriage 69 are driven by a carriage drive motor (not shown). The first and second carriages 68 and 69 have a home position directly below a white reference plate (not shown).

  Under such a configuration, the document reflected light irradiated from the lamp 61 and reflected by the image surface of the document is reflected by the first mirror 63 to the third mirror 65 and introduced into the lens group in the lens barrel 66. The light is condensed by the lens group and formed on the CCD sensor 67. The CCD sensor 67 performs photoelectric conversion processing, and the document image is read as an electrical signal.

  4 is a partially enlarged cross-sectional view showing a configuration around the conveyance guide and the automatic reading glass in FIG. 2, and FIG. 5 is a view of the conveyance guide as viewed from the direction A in FIG. FIG. 6 is a diagram schematically showing the relationship between the arrangement of the document conveying device and the CCD output value, and FIG. 6A is a diagram showing a state where the document conveying device is not tilted. 6B is a diagram illustrating an example of a state where the document conveying device is tilted, and FIG. 6C is a diagram illustrating another example of a state where the document conveying device is tilted.

  FIG. 7 is a diagram illustrating the relationship between the arrangement of the document conveying device and the read image. FIG. 7A is a diagram illustrating the document, and FIG. 7B is a diagram illustrating the document conveying device. FIG. 7C is a diagram illustrating a read image when the document conveying device is tilted to the state of FIG. 6C. is there. Portions common to those in FIG. 2 are denoted by common reference numerals and description thereof is omitted.

  As shown in FIG. 4, the conveyance guide 73 is perpendicular to the document conveyance direction (the direction of the white arrow in the figure) at the position facing the automatic reading glass 25 a from above (the direction perpendicular to the paper surface in the figure). Are arranged along the automatic reading glass 25a to form a part of the document transport path d with the automatic reading glass 25a. Further, the lower surface portion 73a of the conveyance guide 73 is formed in white.

  A predetermined interval is provided between the lower surface portion 73a and the automatic reading glass 25a. When the document passes over the automatic reading glass 25a, the lower surface portion 73a contacts the upper surface of the document from above. This restricts the upward movement of the document. Thus, as described above, the original can be guided downstream while the lower surface of the original is in contact with the automatic reading glass 25a, and the original can be reliably read.

  As shown in FIG. 5, the lower surface portion 73 a has both ends of the longitudinal direction of the image reading device 6 body (hereinafter referred to as the device body) in the front-rear direction (vertical direction with respect to the conveyance direction, left-right direction in the drawing) For example, determination charts (detection patterns) 77a and 77b colored in black are attached.

  The determination chart 77a is affixed to the front side end portion (right end portion in the figure) of the apparatus main body with respect to the front-rear direction of the lower surface portion 73a, and the determination chart 77b is affixed to the rear side end portion (left end portion in the figure). Further, the determination charts 77a and 77b are arranged on both outer sides in the front-rear direction from the first image reading region R1 (shown by hatching in the drawing).

  In the determination chart 77a, the base is arranged along the transport direction (the direction of the white arrow in FIG. 5), and the vertex (intersection A1) formed by the base and the hypotenuse is in contact (intersection) with each other, and the hypotenuse is relative to the base. Are formed from two right triangles arranged on opposite sides. Further, the two right triangles have substantially the same shape, and are arranged so as to be rotated by 180 ° about the intersection A1 and overlap (point symmetry).

  That is, the determination chart 77a is arranged along the transport direction and has an intersection A1 at the center of the determination chart 77a in the transport direction, and the front side (here, the first side) from the intersection A1 toward the upstream side. Is formed so that the width increases toward the downstream side, and the width increases toward the rear side (here, the second end side) toward the downstream side.

  Further, the determination chart 77b has the same shape as the determination chart 77a, and is horizontally reversed with respect to the straight line L0 passing through the center in the front-rear direction of the lower surface portion 73a (parallel to the determination direction). ). That is, the determination chart 77b is arranged along the transport direction, and has an intersection A2 at the center of the determination chart 77b in the transport direction, and the back side (here, the first) from the intersection A2 toward the upstream side. Is formed so that the width increases toward the downstream side, and the width increases toward the front side (here, the second end side) toward the downstream side.

  Thereby, the straight line L1 passing through the intersections A1 and A2 of the two determination charts 77a and 77b is arranged along the front-rear direction. Further, when the document conveying device 27 is inclined on the upper surface of the apparatus main body, the lower surface portion 73a is also inclined accordingly, so that the straight line L1 is also inclined at the same time.

  On the other hand, when detecting the inclination of the document conveying device 27, the first carriage 68 (see FIG. 3) is set in advance so that the light of the lamp 61 reads the intersections A1 and A2 of the determination charts 77a and 77b. It moves to (detection position). As a result, when the document conveying device 27 is not inclined, as shown in FIG. 6A, the reading line Ls of the CCD sensor 67 (see FIG. 3) coincides with the straight line L1 passing through the intersections A1 and A2. .

  In this case, when scanning along the reading line Ls, only the two intersections A1 and A2 are read in addition to the lower surface portion 73a, so the output value (CCD output value, detection result) of the CCD sensor 67 is The reading result of the lower surface portion 73a is represented as a base line, and the intersection points A1 and A2 are represented as substantially linear peaks protruding downward from the base line. At this time, for example, when a document as shown in FIG. 7A is read, a read image having no inclination can be obtained. In addition, let the upper side in FIG. 7 be a conveyance direction (open arrow of a figure).

  However, as shown in FIG. 6B, for example, the back side (left side in the figure) end of the document conveying device 27, that is, the lower surface part 73a is the downstream side (lower side in the figure) in the conveyance direction (white arrow in the figure). 6A, the intersection A2 moves downward from FIG. 6A, and the straight line L1 tilts counterclockwise around the intersection A1. In this case, in the determination chart 77a, the intersection point A1 overlaps the reading line Ls, so that the CCD output value is represented as a linear peak as in FIG. 6A.

  On the other hand, in the determination chart 77b, since the reading line Ls is arranged above the intersection A2, the upper right triangle portion in the determination chart 77b is defined from the base (substantially equivalent to the intersection A2 in the reading line Ls). Cross to the left side over the hypotenuse. Therefore, for the determination chart 77b, the CCD output value protrudes downward from the base line from the intersection A2 to the left side.

  That is, it is represented as a rectangular wave-shaped peak with the intersection A2 as one side on the right side and the width corresponding to the inclination of the lower surface portion 73a as the peak width. At this time, the read image A is inclined as shown in FIG.

  Further, for example, as shown in FIG. 6C, when the rear side (left side in the figure) end of the lower surface part 73a is inclined upstream (upper side in the figure) in the transport direction (white arrow in the figure) The intersection A2 moves upward from FIG. 6A, and the straight line L1 is inclined clockwise with respect to the intersection A1. In such a case, in the determination chart 77a, the intersection A1 overlaps the reading line Ls as in FIG. 6B, so that the CCD output value is represented as a linear peak as in FIG. 6A.

  On the other hand, in the determination chart 77b, since the reading line Ls is arranged below the intersection A2, the lower right triangular portion in the determination chart 77b is substantially equivalent to the base (the intersection A2 in the reading line Ls). ) To the right side from the hypotenuse. Therefore, for the determination chart 77b, the CCD output value protrudes downward from the base line from the intersection A2 to the right side.

  That is, the intersection A2 is represented as a rectangular wave peak having the left side and the width corresponding to the inclination of the lower surface portion 73a as the peak width. At this time, the read image B is inclined as shown in FIG.

  Thus, by detecting the CCD output value at the detection position, the tilt amount can be detected by the tilt direction and the peak width of the document conveying device 27 based on the peak appearance position from the intersection A2. Here, as an example, the case where only the back side (intersection A2 side) of the lower surface portion 73a is tilted is shown, but even when only the front side (intersection A1 side) is tilted, the front side and the back side In the same manner, the tilt direction and the tilt amount of the document conveying device 27 can be detected from the appearance position and peak width of the peak from the intersections A1 and A2 in the CCD output value.

  The CCD output value at the time of tilt detection is transmitted to a control unit (not shown) and displayed on the operation panel 75. A storage unit (not shown) stores in advance a CCD output value when the document conveying device 27 is not tilted as shown in FIG. 6A as a reference output value. The reference output value is displayed on the operation panel 75 together with the CCD output value.

  While the reading line Ls is being read by the CCD sensor 67, the position of the document conveying device 27 is changed so that the CCD output value displayed on the operation panel 75 matches the reference output value. The inclination of the conveying device 27 can be adjusted. In this way, the tilt can be adjusted while visually confirming the CCD output value displayed on the operation panel 75, so that the tilt can be easily adjusted. Note that the control unit and the storage unit can be provided in the image reading apparatus 6 or in the image forming apparatus 100.

  As described above, the CCD sensor 67 reads the lower surface portion 73a with the first and second carriages 68 and 69 stopped at a position facing the lower surface portion 73a of the conveyance guide 73 with the contact glass 25 interposed therebetween. Since the inclination of the document conveying device 27 is detected, it is not necessary to detect the inclination of the document conveying device 27 while moving the first and second carriages 68 and 69. Thereby, it is possible to quickly detect the inclination of the document conveying device 27. It is also possible to detect the inclination of the document conveying device 27 without conveying the document.

  Here, the determination charts 77a and 77b are provided at both ends in the front-rear direction of the lower surface portion 73a, and the CCD sensor 67 detects the inclination by reading the determination charts 77a and 77b. Tilt can be detected. As long as the inclination of the lower surface portion 73a can be detected, the determination charts 77a and 77b are not provided, and the uneven portion formed when the lower surface portion 73a is molded can be read by the CCD sensor 67.

  In addition, here, the determination charts 77a and 77b are arranged along the transport direction, and the intersections A1 and A2 are provided at the center of the determination charts 77a and 77b in the transport direction, and the lower surface from the intersection toward the upstream side. The width and width of the front and rear sides of the portion 73a are widened and the width of the back side and the front side is widened toward the downstream side. Can be detected.

  However, the determination charts 77a and 77b are not particularly limited as long as the inclination of the document conveying device 27 can be detected. In addition, for example, the determination charts 77a and 77b may not be arranged symmetrically as described above, and the same shape as the determination chart 77a may be used as it is in the determination chart 77b, or the same shape as the determination chart 77b may be used as it is as the determination chart 77a. .

  In addition, for example, the determination charts 77a and 77b may be formed in a linear shape that is inclined with respect to the conveying direction, or may be a rectangular shape that is elongated in a direction that is inclined with respect to the conveying direction. Even in such a case, the inclination direction and the inclination amount of the document conveying device 27 can be detected by comparing the peak represented by the CCD output value with the peak of the reference output value.

  Here, since the determination charts 77a and 77b are affixed to the lower surface portion 73a, the determination charts 77a and 77b can be easily formed on the lower surface portion 73a, and the determination charts 77a and 77b are removed or replaced as necessary. Can be effective.

  In addition, if the mark for positioning the determination charts 77a and 77b, such as the recessed part formed in the substantially same shape as these, is formed in the lower surface part 73a, the determination charts 77a and 77b can be affixed accurately. Moreover, the formation method of the determination charts 77a and 77b on the lower surface portion 73a is not particularly limited to the above, and can be formed by printing or the like.

  Here, since the determination charts 77a and 77b are arranged on both outer sides in the front-rear direction with respect to the first image reading region R1 of the automatic reading glass 25a, the inclination of the document conveying device 27 is detected without affecting the image reading. Is possible. However, the arrangement of the determination charts 77a and 77b is not particularly limited as long as the inclination of the document conveying device 27 can be detected. For example, when the image is formed in the first image reading region R1, the determination charts 77a and 77b can be peeled off before the image is read after the tilt adjustment.

  Here, since the operation panel 75 for displaying the CCD output value from the CCD sensor 67 is provided, the inclination of the document conveying device 27 can be adjusted while confirming the inclination on the operation panel 75, and the inclination adjustment is easy and easy. It becomes possible to be efficient. Thereby, the detection of inclination becomes more effective. In addition, since the straight line L1 passing through the intersections A1 and A2 is set as the reading line Ls here, the inclination can be easily detected. However, the reading line Ls is more upstream or downstream in the transport direction than the intersections A1 and A2. It can also be set to the side.

  Further, the CCD output value is not necessarily displayed on the operation panel 75, and can be confirmed by printing the CCD output value on a sheet stored in the sheet feeding mechanism 10. Although the CCD output value is represented as a peak here, it can be displayed as a numerical value as will be described later.

  Next, a method for adjusting the inclination of the document conveying device 27 will be described. FIG. 8 is a schematic perspective view illustrating the periphery of the position adjustment mechanism in the image forming apparatus including the image reading apparatus according to the present embodiment from the back side. FIG. 9 is a schematic perspective view showing the position adjustment mechanism before assembly from the back side of the apparatus main body, and FIG. 10 is a schematic perspective view showing from the front side. Portions common to those in FIG. 1 are denoted by common reference numerals and description thereof is omitted.

  As shown in FIG. 8, on the back side of the image forming apparatus 100 and the image reading apparatus 6, a position adjustment mechanism (position adjustment) is provided at the downstream end of the upper surface of the image reading apparatus 6 in the document transport direction (arrow direction in the figure). Means) 80 is provided. A position adjusting mechanism 80 is also provided at the upstream end (see FIGS. 1 and 13). Since the position adjustment mechanisms 80 provided at the upstream end and the downstream end have the same configuration, the position adjustment mechanism 80 on the downstream side in the transport direction will be described below.

  As shown in FIGS. 9 and 10, the position adjustment mechanism 80 roughly includes a hinge member 81, a position adjustment member 83, a first fixing plate (first fixing member) 85, and a second fixing plate. (Second fixing member) 87 and a position adjusting screw 89 are provided.

  The hinge member 81 is made of metal, and includes a first hinge portion 81a to which the document conveying device 27 is fixed, and a second hinge portion 81b that is rotatably connected to the position adjustment member 83 together with the first hinge portion 81a. And a support shaft 81c that rotatably couples the first hinge portion 81a and the second hinge portion 81b to the position adjusting member 83. The document feeder 27 is fixed to a fixing portion 81aa provided in the first hinge portion 81a and a fixing portion (not shown).

  The position adjusting member 83 is formed by bending a metal plate-like member, and roughly includes a bottom surface portion 83a, a side surface portion 83b, and a back surface portion 83c. The bottom surface portion 83a has a substantially rectangular shape and is sandwiched between a first fixed plate 85 and a second fixed plate 87, which will be described later. In addition, a protruding piece 83aa (see FIGS. 11 and 12) protruding to the front surface side is formed at the front surface side end of the bottom surface portion 83a.

  A first fixing screw 97 (see FIG. 11 and FIG. 12), which will be described later, passes through the bottom surface portion 83a along the front-rear direction (a direction perpendicular to the white direction), and the first fixing screw 97. An elongated hole portion 83ab is formed to enable the position adjusting member 83 to move in the front-rear direction in a state where the through hole penetrates. A first opening 83ac is formed at the center of the bottom surface portion 83a. Such first opening 83ac can prevent the position adjusting member 83 from interfering with a second fixing screw 99 (see FIG. 13) described later.

  The side surface portion 83b protrudes upward from both ends of the bottom surface portion 83a in the conveying direction (in the direction of the white arrow), and the support shaft 81c passes therethrough.

  The back surface portion 83c protrudes upward from the back surface side end portion of the bottom surface portion 83a, and both end portions in the transport direction of the back surface portion 83c are connected to the two side surface portions 83b. Further, a position adjusting screw 89 made of a male screw is passed through the rear surface portion 83c from the rear surface side toward the front surface side and is rotatably supported.

  Specifically, the head of the position adjusting screw 89 is rotatably supported by a recess formed in the back surface portion 83c. In addition, a restriction member 95 is attached to the screw portion from the front side of the back surface portion 83a, and movement of the position adjusting screw 89 in the front-rear direction with respect to the back surface portion 83c is restricted. Thus, when the position adjusting screw 89 moves in the front-rear direction, the position adjusting member 83 moves accordingly (see FIGS. 11 and 12).

  The first fixed plate 85 has a shape in which a metal plate-like member is bent, and roughly includes a support portion 85a and a protruding portion 85b. The support portion 85a has a substantially rectangular shape, is disposed above a second fixing plate 87 described later, and can slidably hold the bottom surface portion 83a of the position adjustment member 83 with the second fixing plate 87. Yes.

  Further, the support portion 85a is formed with a fixing hole portion 85aa disposed on the elongated hole portion 83ab of the position adjusting member 83 and having substantially the same diameter as the first fixing screw 97 (see FIGS. 11 and 12). Has been. Further, the fixing hole 85aa is formed at a position where it overlaps with the elongated hole 83ab even when the position adjusting member 83 moves to the foremost side or the backmost side.

  A first fixing screw 97, which will be described later, passes through the fixing hole 85aa, so that the movement of the first fixing plate 85 is regulated. When fixed to the upper surface of the main body, the position adjusting member 83 is fixed as will be described later.

  Further, both ends in the transport direction of the support portion 85 a are formed along the inner surfaces of the side surface portions 83 b of the position adjusting member 83. Thereby, when the position adjustment member 83 moves in the front-rear direction, both side surface parts 83b can slide with respect to the both ends of the support part 85a, and the position adjustment member 83 is guided in the front-rear direction. Further, the movement of the position adjusting member 83 in the transport direction is restricted, and the position with respect to the first fixed plate 85 is determined in the transport direction.

  The support 85a is formed with a second opening 85ab having a length in the transport direction that is substantially the same as that of the first opening 83ac and that is longer than the first opening 83ac in the front-rear direction. The second opening 85ab is formed across the support portion 85a and the protruding portion 85b. The second opening 85ab prevents the first fixing plate 85 from interfering with a second fixing screw 99 (see FIG. 13) to be described later, like the first opening 83ac of the position adjusting member 83. Can do.

  The protruding portion 85b protrudes upward from the rear side end of the support portion 85a, and a position adjusting screw hole portion 85ba made of a female screw into which the position adjusting screw 89 is screwed is formed in the protruding portion 85b. When the position adjustment screw 89 is screwed into the position adjustment screw hole 85ba and rotates in the direction in which the position adjustment screw 89 is tightened, the position adjustment member 83 approaches the first fixing plate 85 in the front-rear direction and moves to the front side. When it is rotated in the loosened direction, the position adjusting member 83 can be moved away from the first fixed plate 85 and moved to the back side in the front-rear direction (see FIG. 12).

  The second fixing plate 87 has a shape in which a metal plate-like member is bent, and roughly includes a substrate portion 87a and a guide portion 87b. The board portion 87a is fixed to the upper surface of the apparatus main body by a second fixing screw 99 (see FIG. 13) and a screw (not shown).

  The substrate portion 87a is disposed below the support portion 85a of the first fixing plate 85 with the bottom surface portion 83a of the position adjustment member 83 interposed therebetween, so that the bottom surface portion 83a can be slidably held between the support portion 85a. It has become. Further, the board portion 87a is formed with a locking portion 87aa composed of a cut and raised piece in which a part of the board portion 87a is cut and raised in a substantially L shape on the upper side and on the back side. The locking portion 87aa is formed at a position where the protruding piece 83aa of the position adjusting member 83 can be engaged.

  The upward movement of the position adjustment member 83 can be restricted by engaging the protruding piece 83aa with the locking portion 87aa. Accordingly, the position adjusting member 83 can be easily moved even in a temporary assembly state to be described later, and the position adjusting member 83 and the first fixing plate 85 can be more reliably fixed to the upper surface of the apparatus main body during the main assembly. The engaging portion 87aa is formed so as to be able to engage with the protruding piece 83aa even when the position adjusting member 83 is moved to the most back side or the most front side.

  Further, a groove portion 87ab communicating with the rear side end portion of the opening from which the locking portion 87aa is cut out is formed in the substrate portion 87a. The groove portion 87ab is formed to have substantially the same length as the fixing hole portion 85aa of the first fixing plate 85 in the transport direction, and is formed to have a shape substantially coincident with the fixing hole portion 85aa on the back surface side.

  Accordingly, the first fixing screw 97 (see FIGS. 11 and 12) is passed through the fixing hole 85aa, the long hole 83ab of the position adjusting member 83, and the groove 87ab in this order from above, and is twisted on the upper surface of the apparatus main body. Can be included. Further, by setting the first fixing screw 97 in a temporary assembly state in which the first fixing screw 97 is loosely screwed into the upper surface of the apparatus main body, the position adjusting member 83 can be moved, and the first fixing plate 85 is obtained by fastening and performing the main assembly. In addition, the position adjustment member 83 can be fixed to the upper surface of the apparatus main body.

  The guide portion 87b protrudes upward from the upstream end portion in the transport direction of the substrate portion 87a. The guide portion 87b is formed along the outer surface of the side surface portion 83b on the upstream side in the transport direction of the position adjusting member 83, and the upstream side surface portion 83b can slide on the guide portion 87b. With the guide portion 87b, the position adjusting member 83 can be guided in the front-rear direction along with the upstream side edge of the first fixed plate 85 in the transport direction. Further, the position adjusting member 83 is positioned along the guide portion 87b, and the position of the first fixed plate 85 with respect to the upper surface of the apparatus main body is also determined.

  Next, an assembling method and an inclination adjusting operation of the document conveying device 27 will be described. FIG. 11A is a perspective view showing a state in which a position adjustment member used in the position adjustment mechanism has moved to the front side, and FIG. 11B is a cross-sectional view taken along the line BB ′ in FIG. FIG. 11 (c) is a cross-sectional view taken along the CC ′ arrow in FIG. 11 (b).

  12A is a perspective view showing a state in which the position adjusting member has moved to the back side, and FIG. 12B is a cross-sectional view taken along the DD ′ line in FIG. (C) is EE 'arrow sectional drawing of FIG.12 (b). 13A is a schematic perspective view showing a state in which the position adjusting member is fixed to the image reading apparatus main body, and FIG. 13B is a view around the first fixing screw 97 in FIG. 13A. FIG. Portions common to FIGS. 9 and 10 are denoted by common reference numerals and description thereof is omitted.

  First, at the time of production, for example, the second fixing plate 87 is fixed to the upper surface of the apparatus main body with a second fixing screw 99 (see FIG. 13) or the like. On the other hand, the first and second hinge portions 81a and 81b are rotatably connected to the position adjustment member 83 by the support shaft 81c, and the position adjustment screw 89 is attached to the back surface portion 83c of the position adjustment member 83 by the restriction member 95. .

  Further, the support portion 85 a of the first fixing plate 85 is placed on the bottom surface portion 83 a of the position adjustment member 83, and the position adjustment screw 89 supported by the back surface portion 83 c of the position adjustment member 83 is used to adjust the position of the first fixing plate 85. The position adjusting member 83 and the first fixing plate 85 are coupled so that the elongated hole portion 83ab of the position adjusting member 83 overlaps the fixing hole portion 85aa of the first fixing plate 85. Then, the document feeder 27 is fixed to the fixing portion 81aa of the first hinge portion 81a and the fixing portion (not shown).

  Next, the bottom surface portion 83a of the position adjusting member 83 is placed on the substrate portion 87a of the second fixing plate 87, and the first fixing screw 97 is fixed from above to the fixing hole portion 85aa and the bottom surface portion of the support portion 85a. The long hole 83ab of 83a and the groove 87ab of the second fixing plate 87 are passed through in this order, and loosely screwed into a screw hole (not shown) formed on the upper surface of the apparatus main body to perform temporary assembly. Further, for example, after shipment, the user or service person can be in a temporarily assembled state by loosening the first fixing screw 97.

  Then, as shown in FIG. 11, the position adjustment screw 89 is tightened in the position adjustment screw hole 83ba by rotating the position adjustment screw 89 in one direction (for example, clockwise in FIG. 9). With the movement of the position adjusting screw 89, the position adjusting member 83 moves in the front-rear direction (the left-right direction in FIGS. 11B and 11C) so as to approach the first fixing plate 85 (see FIG. To the left). As a result, the downstream end portion in the transport direction of the document transport device 27 together with the hinge portion 81 can be moved to the front side.

  On the other hand, as shown in FIG. 12, the position adjustment screw 89 is loosened from the position adjustment screw hole 85ba by rotating the position adjustment screw 89 in the opposite direction to FIG. 11 (for example, counterclockwise in FIG. 9). . With the movement of the position adjusting screw 89, the position adjusting member 83 is separated from the first fixing plate 85 in the front-rear direction (the left-right direction in FIGS. 12B and 12C). To the right). As a result, the downstream end of the document conveying device 27 in the conveying direction can be moved to the back side together with the hinge portion 81.

  Note that the upstream end of the document transport device 27 is also moved to the front side and the back side by the position adjusting mechanism 80 disposed at the upstream end of the document transport device 27 in the transport direction. Can do. After moving the document conveying device 27 in this manner, as shown in FIG. 13, the first fixing screw 97 is fastened, whereby the position adjusting member 83 is moved to the first fixing plate 85 and the second fixing plate 87. And the position adjusting member 83 and the first fixing plate 85 can be fixed to the apparatus main body.

  Next, an inclination adjustment operation of the document conveying device 27 based on the above-described inclination detection result of the document conveying device 27 will be described.

  When the position adjustment mechanism 80 is temporarily assembled by a user, serviceman, manufacturer, or the like (hereinafter referred to as a user) and the tilt detection mode is selected on the operation panel 75, the first carriage 68 is moved from the home position. The intersections A1 and A2 are moved to the readable position immediately below the determination patterns 77a and 77b, and the second carriage 69 is moved in accordance with the movement of the first carriage 69.

  When the lamp 61 is irradiated along the reading line Ls and the reflected light is read by the CCD sensor 67 with the first and second carriages 68 and 69 stopped at the detection position, the CCD output value is displayed on the operation panel 75. Is done. For example, the CCD output value shown in FIG. 6A is set as the reference output value, and the reference output value is displayed on the operation panel 75 together with the CCD output value.

  The user or the like visually observes the CCD output value displayed on the operation panel 75, and when the document conveying device 27 is tilted as shown in FIG. 6B or FIG. At least one position adjusting screw 89 of the position adjusting mechanism 80 provided on the upstream side and the downstream side is rotated to move at least one of the upstream side and downstream side end portions of the document conveying device 27 in the front-rear direction.

  Then, when the peak appearance position and peak width of the CCD output value match the peak appearance position and peak width of the reference output value on the operation panel 75, the rotation of the position adjusting screw 89 is stopped. Thereby, the inclination of the document conveying device 27 can be adjusted. Thereafter, the main assembly is performed by fastening the first fixing screw 97. When the document conveying device 27 is not tilted in the temporary assembly state and the CCD output value matches the reference output value, the first fixing screw 97 is fastened and the main assembly is performed.

  Here, the inclination of the document conveying device 27 is displayed by the peak waveform of the CCD output value and the reference output value, but these can also be displayed as numerical values. In such a case, for example, the peak appearance position and peak width of the reference output value are stored as reference numerical values in a storage unit (not shown), and the control unit (not shown) shifts the peak appearance position of the CCD output value from the reference output value ( For example, the calculation result can be calculated by calculating as the inclination direction and the deviation amount of the peak width (for example, expressed in millimeters) as the inclination amount.

  In such a case, the relationship between the tilt direction and the rotation direction of the position adjustment screw 89 and the relationship between the tilt amount and the rotation amount of the position adjustment screw 89 are also stored in the storage unit in advance, and the calculation result by the control unit is used. The rotation direction and the rotation amount of the position adjusting screw 89 can be displayed on the operation panel 75. In addition, a scale corresponding to the displayed rotation amount can be formed on the position adjustment screw 89, which makes it easier to adjust the inclination of the document conveying device 27.

  In addition, by performing automatic document conveyance in a state where the inclination of the document conveying device 27 is adjusted as described above, it is possible to prevent the reading image from being inclined due to the inclination of the document conveying device 27.

  As described above, the document adjustment device 80 is provided at both ends in the conveyance direction on the back side so that the document conveyance device 27 can be opened and closed, and the positions of the both ends in the conveyance direction can be adjusted along the front-rear direction. The inclination of the document conveying device 27 can be adjusted only by changing the positions of both ends in the conveying direction of the conveying device 27 in the front-rear direction. Thereby, the inclination of the document conveying device 27 can be adjusted easily and efficiently.

  Further, here, the position adjustment mechanism 80 is provided with a hinge member 81, a position adjustment member 83 to which the document feeder 27 is fixed via the hinge member 81, and above the upper surface of the apparatus main body with the position adjustment member 83 interposed therebetween. The first fixing plate 85 and the first fixing plate 85 that are disposed and slidably hold the position adjusting member 83 with the upper surface of the apparatus main body along the front-rear direction and can be fixed to the upper surface of the apparatus main body at a predetermined position. On the other hand, since the position adjusting screw 89 for connecting the position adjusting member 83 so as to be movable in the front-rear direction is provided, the positions of both ends in the conveying direction of the document conveying device 27 can be changed by simply rotating the position adjusting screw 89. can do. Thereby, the inclination of the document conveying device 27 can be adjusted more easily and efficiently.

  Further, here, it is fixed to the upper surface of the apparatus main body and is disposed below the first fixed plate 85 with the position adjusting member 83 interposed therebetween, and can be slid in the front-rear direction with the position adjusting member 83 sandwiched between the first fixed plate 85. Since the second fixing plate 87 that can position the first fixing plate 85 with respect to the upper surface of the apparatus main body is provided, the moving direction and the moving amount of the position adjusting member 83 relative to the first fixing plate 85 can be more reliably determined. Can be.

  Further, the moving direction and the moving amount of the position adjusting member 83 with respect to the apparatus main body can be made more reliable. Thereby, the adjustment accuracy of the inclination of the document conveying means can be improved. The second fixing plate 87 is not an essential component of the present invention, and may be configured without the second fixing plate 87. In addition, a recess or the like that enables positioning of the first fixing plate 85 can be formed on the upper surface of the apparatus main body.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention. For example, the configuration of the position adjustment mechanism 80 shown in the above embodiment is merely an example, and supports the document transport device 27 so that it can be opened and closed, and can move both ends in the transport direction of the document transport device 27 in the front-rear direction. Other configurations may be used depending on the device configuration.

  Further, the shape of the conveyance guide 73, the hinge member 81, the position adjusting member 83, the first fixing plate 85, the second fixing plate 87, the position adjusting screw 89, and the like shown in the above embodiment are also particularly limited to the above embodiment. However, it can be appropriately set according to the apparatus configuration and the like. In the above embodiment, the operation panel 75 is provided in the image forming apparatus 100 and is shared by the image reading apparatus 6 and the image forming apparatus 100. However, the operation panel 75 may be provided exclusively for the image reading apparatus 6 or the like. .

  In the above embodiment, the image reading device 6 is a unit in which the pickup roller 33 and the paper feed belt 34 are unitized. However, the pickup roller 33 may be provided separately from the paper feed belt 34. A configuration in which a paper feed roller is disposed in place of the paper feed belt 34 and a configuration in which a separation pad is disposed in place of the separation roller 35 are also possible.

  The present invention detects the inclination of the document conveying means by the image reading unit reading the lower surface portion while the scanning device is stopped at a position facing the lower surface portion of the guide member with the contact glass interposed therebetween. .

  As a result, it is possible to quickly detect the inclination of the document conveying means, thereby improving workability. In addition, it is possible to detect the inclination more reliably by providing detection patterns at both ends in the vertical direction on the lower surface and detecting the inclination by the image reading unit reading the detection pattern.

  Further, the detection pattern is arranged along the transport direction, and in the transport direction, the detection pattern has an intersection at the center of the detection pattern, and the first end in the vertical direction of the lower surface from the intersection toward the upstream side. The width and the amount of inclination are easy and reliable by forming the width to the second end side opposite to the first end side toward the downstream side. Can be detected. Moreover, it becomes effective by sticking the pattern for a detection to a lower surface part.

  In addition, by arranging the detection patterns on both outer sides in the vertical direction with respect to the image reading area, it is possible to detect the inclination without affecting the image reading. Further, by providing a display means for displaying the result of detecting the tilt by the image reading unit, the detection of the tilt becomes more effective. Further, by providing position adjustment means that supports the document conveyance means so that the document conveyance means can be opened and closed and can adjust the positions of both ends along the vertical direction at both ends in the conveyance direction on one end side in the vertical direction of the document conveyance means. In addition, the tilt can be adjusted efficiently.

  Further, by providing the position adjusting means with the hinge member, the position adjusting member, the first fixing member, and the position adjusting screw, the tilt can be adjusted more easily and efficiently. In addition, by providing the second fixing member, it is possible to increase the inclination adjustment accuracy. Further, by making it possible to adjust the tilt by the position adjusting means based on the tilt detection result by the image reading unit, it becomes more efficient and effective. Further, by using the image forming apparatus on which the image reading apparatus is mounted, it is possible to perform image formation in which image defects due to the inclination of the document conveying unit are prevented.

6 Image reading device 25 Contact glass 25a Glass for automatic reading 25b Glass for manually placed document 27 Document conveying device (document conveying means)
68 First carriage (scanning means)
69 Second carriage (scanning means)
67 CCD sensor (image reading unit)
73 Conveyance guide (guide member)
73a Lower surface 75 Operation panel (display means)
77a, 77b judgment chart (detection pattern)
80 Position adjustment mechanism (position adjustment means)
81 hinge member 81a first hinge part 81b second hinge part 81c support shaft 83 position adjusting member 83a bottom face part 83aa protruding piece 83ab long hole part 83b side face part 83c back face part 85 first fixing plate (first fixing member)
85a Supporting portion 85aa Fixing hole portion 85b Protruding portion 85ba Position adjusting screw hole portion 87 Second fixing plate (second fixing member)
87a Substrate part 87aa Locking part 87ab Groove part 87b Guide part 89 Position adjusting screw 95 Restriction member 97 First fixing screw 100 Image forming apparatus A1, A2 Intersection R1 First image reading area (image reading area)
R2 Second image reading area

Claims (11)

A contact glass disposed on the upper surface of the apparatus body;
Document conveying means that can be opened and closed upward with respect to the contact glass, and conveys the document to the upper surface of the contact glass;
A guide member which is arranged along the direction perpendicular to the document conveying direction to the document conveying means, is opposed to the upper surface of the contact glass at a predetermined interval, and guides the document;
An image reading unit disposed below the contact glass;
A scanning unit that irradiates the original with light from below the contact glass and guides reflected light to the image reading unit,
The image reading unit reads the lower surface portion in a state where the scanning unit stops at a position facing the lower surface portion of the guide member with the contact glass interposed therebetween, thereby detecting the inclination of the document conveying unit. An image reading apparatus. Detection patterns are provided at both ends in the vertical direction on the lower surface,
The image reading apparatus according to claim 1, wherein the inclination is detected by the image reading unit reading the detection pattern.   The detection pattern is arranged along the transport direction, and has an intersection at the center of the detection pattern in the transport direction, and the vertical direction of the lower surface portion extends from the intersection toward the upstream side. The first end portion side is widened, and the second end portion side opposite to the first end side is widened toward the downstream side. Item 3. The image reading apparatus according to Item 2.   The image reading apparatus according to claim 2, wherein the detection pattern is attached to the lower surface portion.   The image reading apparatus according to claim 2, wherein the detection patterns are arranged on both outer sides in the vertical direction with respect to the image reading area.   The image reading apparatus according to claim 1, further comprising a display unit that displays a detection result of the tilt by the image reading unit.   Position adjusting means that is disposed at both ends in the conveying direction on the one end side in the vertical direction of the document conveying means, supports the document conveying means so as to be openable and closable, and adjusts the positions of the both ends along the vertical direction. The image reading apparatus according to claim 1, further comprising: The position adjusting means includes a hinge member,
A position adjusting member to which the document conveying means is fixed via the hinge member;
The apparatus is disposed above the upper surface of the apparatus main body with the position adjustment member interposed therebetween, and the position adjustment member is slidably held along the vertical direction with the upper surface of the apparatus main body and at the predetermined position. A first fixing member that can be fixed to
The image reading apparatus according to claim 7, further comprising: a position adjusting screw that connects the position adjusting member to the first fixing member so as to be movable along the vertical direction.   Fixed to the upper surface of the apparatus main body and disposed below the first fixing member with the position adjusting member interposed therebetween, and slidable in the vertical direction with the position adjusting member sandwiched between the first fixing member. The image reading apparatus according to claim 7, further comprising a second fixing member that is sandwiched between the first fixing member and the first fixing member so that the first fixing member can be positioned with respect to the upper surface of the apparatus main body.   The image reading apparatus according to claim 7, wherein the inclination can be adjusted by the position adjusting unit based on a detection result of the inclination by the image reading unit.   An image forming apparatus on which the image reading apparatus according to claim 1 is mounted.

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