JP2005167817A - Image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for adjusting a position of a contact image sensor (CIS) in a direction orthogonal to an original transport direction when a distance from the CIS to an original is dissident from a focal distance of the CIS single body due to a manufacturing error or the like of each member configuring an upper guide member for forming a transport path in an image reading apparatus provided with the CIS. <P>SOLUTION: In the image reading apparatus 1, receiving members 40 each provided with a receiving face 37a for receiving each of a read means support part 42 are attached to both ends of the CIS 10, the read means support parts 42 each having a screw hole 46 formed in an upper face and being provided projectingly at both ends in an original width direction respectively at a bottom 34 of an upper guide member main body 36 forming a lowermost stream part of the transport path 9. The CIS 10 is arranged so that each receiving face 37a is placed on each read means support part 42 in a connectable / disconnectable way, and a height adjustment screw 41 is screwed to the screw hole 46 in a retractable way from the upper face of the read means support part 42. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image reading apparatus including a contact image sensor that reads one side of a document, and more particularly to an image reading apparatus that can adjust the position of the contact image sensor in a direction perpendicular to the document conveyance direction. is there.

  Some copiers, fax machines, scanners, and the like include an image reading device that reads one side of a document with a contact image sensor. FIG. 10 is a schematic longitudinal sectional view showing an example of an image reading unit in a conventional image reading apparatus (see Patent Document 1). As shown in the figure, the image reading unit 70 is a so-called contact image sensor (hereinafter referred to as “CIS”) 71 that reads a document image in close contact with a document P conveyed on a conveyance path (not shown). And a reading means 74 having a holding bracket 73 attached to the side surface of the CIS 71 and projecting a support shaft 72, a bearing portion 76 having an opening 75, and a bearing groove 77 communicating with the bearing portion 76. A pair of left and right side surface portions 78 and a mounting bracket 80 constituted by a connecting portion 79 that connects these side surface portions 78, a leaf spring 81 attached to the connecting portion 79 of the mounting bracket 80, and a rotating support shaft 82. A platen roller 84 having bearings 83 attached to both ends is provided. When assembling the image reading unit 70, first, the reading unit 74 is supported on the mounting bracket 80 by inserting the support shaft 72 of the holding bracket 73 from the opening 75 of the bearing unit 76 into the bearing groove 77. Next, the platen roller 84 is rotatably supported on the mounting bracket 80 by fitting the bearing 83 to the bearing portion 76. In this manner, the side surface portion 78 of the mounting bracket 80 that is unitized by supporting the reading means 74 and the platen roller 84 is fixed to a frame (not shown) inside the copying machine or the like by screw fastening or the like.

  In the image reading unit 70 configured as described above, since the bearing 83 fitted to the bearing unit 76 is fixed to the bearing unit 76 with the vertical and horizontal movements restricted, the CIS 71 includes the platen roller 84 and the plate. It is held so as to be clamped by the spring 81. Accordingly, the document P transported through a transport path (not shown) is brought into close contact with the CIS 71 by the platen roller 84. At this time, the distance from the CIS 71 to the original P is equal to the focal length of the CIS 71, and good image reading by the CIS 71 is possible.

JP-A-5-236199

  However, the CIS 71 individual has a distance from the CIS 71 to the original P due to the accumulation of manufacturing errors and assembly errors of each member constituting the image reading unit 70 and due to variations in focal length among the individual CIS 71 individual. In some cases, it does not coincide with the focal length, and the reading accuracy is deteriorated to cause an image defect. However, in the conventional image reading apparatus, there is no means for adjusting the position of the CIS 71 in the direction orthogonal to the document conveyance direction, and thus there is a problem that the image defect problem cannot be solved.

  The present invention has been made in view of such a problem. In an image reading apparatus having a CIS for reading one side of an original, an accumulation of manufacturing errors and assembly errors of each member constituting the upper guide member, etc. In addition, when the distance from the CIS to the document does not match the focal length of the CIS individual due to the variation in the focal length among the CIS individuals, the position of the CIS is set as the document conveyance direction. Means that can be adjusted in an orthogonal direction are provided.

  The invention of claim 1 for achieving the above object is provided at both ends of the document width direction at the bottom of the upper guide member main body disposed on the upper side of the pair of upper and lower guide members forming the most downstream portion of the conveyance path. A reading means supporting portion having a screw hole formed on the upper surface is projected, and receiving members each having a receiving surface for receiving the reading means supporting portion are attached to both ends, and one of the documents conveyed on the conveying path A contact type image sensor that reads the surface of the contact type is disposed so that each receiving surface is detachably mounted on each reading unit support part, and a height for adjusting the height position of the contact type image sensor from the document is adjusted. A height adjusting screw is screwed into the screw hole so as to be able to project and retract from the upper surface of the reading means supporting portion.

  According to a second aspect of the present invention, the upper guide member main body is attached so as to be openable and closable so as to expose the most downstream portion of the transport path, and the screw hole reaches the bottom surface of the upper guide member main body. The height adjusting screw is formed and screwed into the screw hole from the bottom surface side of the upper guide member main body.

  According to a third aspect of the present invention, the most downstream portion of the transport path is formed horizontally.

  According to the image reading apparatus of the present invention, among the pair of upper and lower guide members forming the most downstream portion of the conveyance path, the upper surface of the upper guide member main body disposed on the upper side is screwed on both ends in the document width direction. A reading means supporting portion formed with a hole is protruded, receiving members each having a receiving surface for receiving the reading means supporting portion are attached to both ends, and one side of the original conveyed on the conveying path is attached A CIS to be read is arranged with each receiving surface placed on each reading means supporting portion so as to be able to contact and separate, and a height adjusting screw for adjusting the height position of the CIS from the document is provided from the upper surface of the reading means supporting portion. Since it is screwed into the screw hole so as to be able to appear and retract, by turning the height adjustment screw in the advancing direction, the tip of the height adjustment screw protrudes from the upper surface of the reading means support part and pushes up the receiving surface, Because one end of the CIS is lifted The position of the CIS, can be adjusted in the direction perpendicular to the document transportation direction. As a result, due to the accumulation of manufacturing errors and assembly errors of each member constituting the upper guide member, and due to variations in the focal length among CIS individuals, the distance from the CIS to the document is equal to the focal length of the CIS individual. If the image quality is not matched and the reading accuracy is deteriorated and an image defect occurs, the CIS position is adjusted in a direction orthogonal to the document conveyance direction, and the distance from the CIS to the document is adjusted to the focal length of the CIS. Good image reading can be performed.

  Further, according to the present invention, the upper guide member body is attached so as to be openable and closable so as to expose the most downstream part of the transport path, and is formed so that the screw hole reaches the bottom surface of the upper guide member body. Since the height adjustment screw is screwed into the screw hole from the bottom surface side of the upper guide member body, when the CIS position is to be adjusted in the direction perpendicular to the document conveying direction, the upper frame is opened and the intermediate second frame is By turning about 90 degrees with the fixed shaft as a fulcrum, the height adjusting screw can be turned from the bottom side of the upper guide member body using a screwdriver or the like. This makes it possible to easily adjust the position of the CIS without removing the intermediate frame from the image reading apparatus and disassembling it.

  In addition, according to the present invention, since the most downstream portion of the conveyance path is formed horizontally, the receiving member placed on the reading means support portion does not shift in the document conveyance direction due to its own weight, which is favorable. Image reading can be performed. Further, it is possible to omit a biasing spring that biases the CIS downward and presses the horizontal portion of the receiving member against the reading means support portion.

  In an image reading apparatus having a contact image sensor that reads one surface of a document conveyed on a transport path, the contact image sensor may be caused by accumulated manufacturing errors and assembly errors of each member constituting the upper guide member. The purpose is to prevent the problem that the distance from the contact image sensor to the original does not match the focal length due to the variation in the focal length among individuals, and the purpose is to minimize the number of parts and the cost. Realized.

  Hereinafter, an image reading apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view showing the configuration of the image reading apparatus 1. The image reading apparatus 1 includes an FBS 3 provided on the main body frame 2 and an ADF 5 provided on the document pressing plate 4. Although not shown in detail in the figure, the FBS 3 is used when reading a thick original P or the like, and an image of the surface of the original P placed on the platen glass 6 of the main body frame 2 is movable. Are read by the reading means 7. On the other hand, the ADF 5 is used when reading a sheet-like document P. The document P set on the sheet feed tray 8 is separated from the top sheet Pt one by one and sent to the conveyance path 9. The image on the front surface of the document P is read by the reading means 7, and the image on the back surface is read by the contact image sensor (CIS) 10 and discharged to the paper discharge tray 11. In the image reading apparatus 1, the reading unit 7 has an arbitrary configuration, and the CIS 10 may be configured to read only one side of the document P.

  As shown in FIG. 1, the ADF 5 has a paper feed tray 8 on which a bundle of originals P to be read is placed, and a pickup that takes out the uppermost paper Pt from the bundle of originals P and feeds it from the paper feed port to the transport path 9. The roller 12, the separation roller 13, the separation pad 14, a horizontal U-shaped conveyance path 9 that connects the paper feed tray 8 and the paper discharge tray 11, a feed roller 15, and a press roller 16. A conveying roller 17 that is appropriately disposed on the conveying roller 17 to convey the document P downstream, a pressing spring 18 that presses the press roller 16 against the feed roller 15, a pressing spring mounting member 19 that is fitted with the pressing spring 18, and conveying The reading means 7 disposed at the lowermost position of the path 9, the CIS 10 disposed on the downstream side of the reading means 7, and the reading glass 20 disposed immediately below the CIS 10 are rotatably pressed against the original P A platen roller 21 brought into close contact with the reading glass 20, a discharge roller 22 disposed at the most downstream end of the conveyance path 9, a pressure roller 23 pressed against the discharge roller 22, and a document P discharged from the discharge port are received. A discharge assisting rib 24 for guiding the discharge tray 11, the rear end portion of the discharged document P from the peripheral surface of the discharge roller 22 to the discharge tray 11, and a lead sensor 25 for detecting the completion of the discharge of the document P. Are provided. In this embodiment, as shown in the figure, the ADF 5 is composed of an upper frame 26, an intermediate first frame 27, an intermediate second frame 28, and a lower frame 29, and the respective members are attached to the respective frames. .

  The reading means 7 includes a light source S for irradiating the document P conveyed on the conveyance path 9 through the platen glass 6 on the main body frame 2 and a reflection mirror M for guiding the reflected light from the document P in a predetermined direction. A so-called CCD image sensor comprising a lens L for converging the reflected light, and a charge coupled device (hereinafter referred to as “CCD”) Q for converting the converged light into an electric signal. As shown in the figure, it is a movable image reading means disposed so as to be movable in the horizontal direction below the conveyance path 9.

  That is, the reading unit 7 is used as a reading unit for both the FBS 3 and the ADF 5. When the document P is read by the FBS 3, the reading unit 7 moves in the horizontal direction below the platen glass 6 to read the document P, and the ADF 5 When the original P is read, it moves to the reading position X. In this way, the images of the original P that are conveyed along the conveyance path 9 and pass immediately above the reading position X are sequentially read.

  As shown in FIG. 1, the conveyance path 9 is a substantially U-shaped conveyance path that connects the paper feed tray 8 and the paper discharge tray 11, and includes an upper frame 26, an intermediate first frame 27, and an intermediate second frame 28. And the lower frame 29 are formed to face each other at a predetermined interval. In particular, the most downstream portion of the conveyance path 9 is formed to be substantially horizontal by an intermediate second frame 28 and a lower frame 29 disposed below the intermediate second frame 28, and the document P is discharged from the discharge port. However, the present invention is not limited to this, and it is also possible to incline the most downstream portion of the conveyance path 9 obliquely upward and discharge the original P obliquely upward from the discharge port. Further, the upper end portion of the intermediate second frame 28 is attached so as to be openable and closable with respect to a fixed shaft 30 whose both end portions are fixed to a frame (not shown) of the image reading apparatus 1. As a result, when a paper jam occurs inside the image reading apparatus 1, the upper frame 26 is opened upward with the hinge 31 as a fulcrum as shown in FIG. By rotating upward as a fulcrum, the most downstream portion of the conveyance path 9 is exposed, and the document P jammed in the conveyance path 9 can be taken out.

  As shown in FIG. 1, the intermediate second frame 28 includes an upper guide member 32 that forms an upper side of the most downstream portion of the conveyance path 9, and a lid member 33 that is attached so as to cover the upper portion of the upper guide member 32. It comprises. The upper guide member 32 is provided with engaging claws 34 at both ends in the document conveying direction. The upper guide member 32 is engaged with an engaging groove 35 formed in the lid member 33 to engage the upper guide. A lid member 33 is attached to the upper part of the member 32. Here, the vertical width of the engagement groove 35 is formed to be slightly larger than the thickness of the engagement claw 34, and when the engagement claw 34 is engaged with the engagement groove 35, the engagement claw 34 and the engagement groove 35 There is some play in the vertical direction between them. Thus, the upper guide member 32 and the upper lid member 33 can move up and down relative to each other by this amount of play. Furthermore, as shown in the figure, one end of an urging spring 36 is attached to the upper guide member 32, and the other end of the urging spring 36 is attached to a lid member 33. The upper guide member 32 is urged downward by the urging spring 36 because the upward movement of the upper frame 26 is restricted by abutting a projecting piece (not shown) projecting downward on the inner surface of the upper frame 26. Has been.

  2 to 5 are views showing the configuration of the upper guide member 32. FIG. 2 is a schematic perspective view, FIG. 3 is a schematic bottom view, FIG. 4 is a cross-sectional view taken along the line AA in FIG. It is a disassembled perspective view which shows the attachment structure to the upper guide member main body of CIS10. As shown in FIGS. 2 to 5, the upper guide member 32 includes a horizontal portion 40, an upper guide member main body 39 formed by fitting the reading glass 20 in a glass mounting hole 38 formed through the bottom portion 37. A CIS 10 in which positioning members 43 each having a vertical portion 41 and an attachment portion 42 are attached to both ends, a height adjusting screw 44 for adjusting the position of the CIS 10 in a direction perpendicular to the document conveying direction, and the discharge A pressing roller 23 pressed against the roller 22 is attached.

  As shown in FIG. 2, the upper guide member main body 39 is a member made of a resin or the like having a substantially box shape with an upper portion opened. As shown in FIGS. 2 and 5, the upper guide member main body 39 includes a reading means support portion 45 projecting from both ends of the bottom portion 37 in the document width direction, and an inner side of the reading means support portion 45 in the document width direction. An insertion hole 46 formed in the document, a biasing spring mounting portion 47 projecting from the insertion hole 46 in the document width direction and to which the biasing spring 36 is attached, and engagement provided at both ends of the document conveying direction. The claw 34 is provided.

  As shown in FIGS. 4 and 5, the reading means support portion 45 is for supporting both ends of the CIS 10 from below, and is provided at both ends of the upper guide member body 39 in the document width direction from above the bottom 37. It is provided to protrude to each. The reading means support portion 45 has a cylindrical shape, and its upper surface is formed as a flat surface so that both end portions of the CIS 10 can be stably placed. Further, the reading means support portion 45 is formed with a screw hole 48 extending from the upper surface to the bottom surface 39 a of the upper guide member main body 39. The shape of the reading means support portion 45 is not limited to a cylindrical shape, and may be, for example, a prismatic shape, has a predetermined height dimension so that both ends of the CIS 10 can be supported from below, and the screw holes 48 are formed. If formed, the design can be changed as appropriate.

  The insertion holes 46 are through which the vertical portions 41 of the positioning members 43 attached to both ends of the CIS 10 are inserted. As shown in FIGS. 4 and 5, on the inner side in the document width direction of the reading means support portion 45, It is formed so as to penetrate the bottom portion 37. The insertion hole 46 is substantially rectangular in cross section, and has a document conveyance direction dimension larger than the document conveyance direction dimension of the vertical portion 41 of the positioning member 43, and the document width direction dimension is the vertical portion 41 dimension. It is formed to be approximately equal to or slightly larger than the document width direction dimension. Thereby, in a state where the vertical portion 41 is inserted into the insertion hole 46, the CIS 10 is movable in both the document conveying direction and the vertical direction.

  FIG. 6 is an exploded perspective view showing the configuration of the CIS 10. As shown in the drawing, the CIS 10 includes a CIS main body 49 and a pair of left and right positioning members 43 attached to both ends of the CIS main body 49 in the longitudinal direction. Although not shown in detail in the figure, the CIS main body 49 irradiates light from a light source onto a document P that is in close contact with the reading glass 20 disposed immediately below the CIS main body 49 and converges the reflected light on the photoconductive element with a converging fiber. This is a fixed reading means. In order for the CIS main body 49 to read an image with high accuracy, the distance from the CIS main body 49 to the document P needs to coincide with the focal length of the CIS main body 49. In addition, through holes 50 for attaching the positioning members 43 are formed at both ends of the CIS main body 49. In the present embodiment, the CIS main body 49 and the positioning member 43 are configured as separate members, but it is also possible to integrally form both.

  The positioning member (receiving member) 43 is positioned at a position in the document transport direction of the CIS 10 and a position perpendicular to the document transport direction with respect to the document P transported on the transport path 9, which is a height from the document P in this embodiment. The position is positioned. 7 and 8 are views showing the configuration of the positioning member 43, FIG. 7 is a schematic perspective view, and FIG. 8 is a schematic bottom view. As shown in the figure, the positioning member 43 includes a horizontal portion 40 for positioning the height position of the CIS 10 from the document P, a vertical portion 41 for positioning in the document transport direction, and an attachment portion for attaching to the CIS main body 49. 42.

  As shown in FIGS. 7 and 8, the horizontal portion 40 is a flat plate member, and the back surface thereof is a receiving surface 40 a that is a surface that receives the reading unit support portion 45. In this embodiment, the receiving surface 40a is formed as a flat surface, and the upper surface of the reading means support portion 45 is formed as a flat surface, so that both end portions of the CIS 10 are stably placed on the reading means support portion 45. It can be placed.

  As shown in FIGS. 7 and 8, the vertical portion 41 extends downward from the one end portion of the horizontal portion 40 substantially perpendicular to the horizontal portion 40, and has a U-shape that opens downward at the lower end portion thereof. A U-shaped groove 41a, which is a groove, is formed. As shown in FIG. 4, the shape of the U-shaped groove 41a is not limited to the U-shape as long as it fits with the roller shaft 21a of the platen roller 21. For example, the U-shaped groove 41a may be a concave groove. is there. However, it is preferable that the width of the U-shaped groove 41a in the document conveyance direction is substantially equal to the outer diameter of the roller shaft 21a so that the vertical portion 41 is not displaced in the document conveyance direction when fitted to the roller shaft 21a. . As a result, the CIS 10 can reliably position the document P in the document transport direction and can perform good image reading.

  As shown in FIG. 7, the attachment portion 42 has a substantially cylindrical shape protruding from the upper portion of the horizontal portion 40, and its upper end portion is formed to have a small diameter. Further, a screw hole 51 is formed in the attachment portion 42 from the upper end side. As shown in FIG. 6, the upper end portion of the mounting portion 42 is fitted into the through hole 50 of the CIS main body 49, and the screw 52 is screwed into the screw hole 51, thereby positioning the positioning member 43 at both ends of the CIS main body 49. It is fixed to each part.

  As shown in FIG. 5, the CIS 10 configured as described above has the vertical portions 41 of the positioning members 43 attached to both ends thereof inserted into the insertion holes 46, and the receiving surface 40a of the horizontal portion 40 is read by the reading means. It is arranged by being placed on the support portion 45 so as to be able to come into contact with and away from it, and is movable in both the document conveying direction and the vertical direction. In the present invention, “contactable / separable” refers to a configuration in which the receiving surface 40a and the reading means support portion 45 are joined, and the two can be separated by applying a force to the receiving surface 40a. Further, as shown in FIG. 1, one end of an urging spring 53 is fixed to the upper surface of the CIS 10, and the other end of the urging spring 53 is fixed to a lid member 33. Since the upward movement of the frame 26 is restricted by contact with a projecting piece (not shown) projecting downward on the inner surface of the frame 26, the CIS 10 is urged downward by the urging spring 53, and the receiving surface. 40 a is in pressure contact with the reading means support portion 45. Therefore, even when the most downstream portion of the conveyance path 9 is inclined upward, the CIS 10 can perform good image reading without being displaced in the document conveyance direction due to its own weight. However, in this embodiment, the most downstream portion of the conveyance path 9 is formed horizontally, and the CIS 10 placed on the reading means support unit 45 is not displaced in the document conveyance direction by its own weight. The urging spring 53 can be omitted.

  4A is a cross-sectional view taken along the line AA in FIG. 2 in a state in which the CIS 10 is attached to the upper guide member main body 39. As shown in FIG. 4A, the upper guide member main body 39 includes an urging spring. The reading glass 20 disposed at the bottom 37 is pressed against the platen roller 21. As a result, the document P transported through the transport path 9 is brought into close contact with the reading glass 20 by the platen roller 21. On the other hand, both ends of the CIS 10 are placed on the reading unit support unit 45 and are pressed against the reading unit support unit 45 by its own weight and by the biasing force received from the biasing spring 53. At this time, the distance D1 from the CIS main body 49 to the document P that is in close contact with the reading glass 20 is equal to the focal length of the CIS main body 49, and good image reading by the CIS main body 49 is possible. .

  The height adjusting screw 44 is for adjusting the height position of the CIS 10 from the document P so as to coincide with the focal length of the CIS main body 49 so that it can protrude from the upper surface of the reading means support portion 45. It is screwed into the screw hole 48. In this embodiment, as shown in FIGS. 4 and 5, the screw hole 48 is formed so as to reach the bottom surface 39 a of the upper guide member main body 39 from the upper surface of the reading means support portion 45, and is longer than the screw hole 48. A height adjusting screw 44 having a screw portion 44 a is screwed into the screw hole 48 from the bottom surface 39 a side of the upper guide member main body 39. As shown in FIG. 4A, the tip of the height adjusting screw 44 is substantially flush with the upper surface of the reading means support section 45, and when the CIS 10 is placed on the reading means support section 45, The tip of the height adjusting screw 44 is in contact with the receiving surface 40a. As a result, the height adjusting screw 44 is rotated in the advancing direction, and as shown in FIG. When the CIS 10 is too far from the original P, the height adjusting screw 44 can be rotated in the backward direction to bring the CIS 10 closer to the original P. Accordingly, the distance from the CIS main body 49 to the document P is determined by the accumulated manufacturing error and assembly error of each member constituting the upper guide member 32, and by the variation in the focal length among the individual CIS 10 members. When an image defect occurs because the focal length of the main body 49 does not match, the height position from the original P is adjusted by the height adjusting screw 44 at both ends of the CIS 10, and the distance from the CIS main body 49 to the original P is adjusted. By matching the distance D2 with the focal length of the CIS main body 49, it is possible to perform good image reading by the CIS 10. The height adjusting screw 44 is not limited to the one having the screw portion 44a longer than the screw hole 48. For example, although not shown in detail in the drawing, the head does not have a head and covers the entire length like a so-called set screw. It is also possible to screw the one having a screw part so as to be buried in the screw hole.

  In this embodiment, since the height adjusting screw 44 is screwed into the screw hole 48 from the bottom surface 39a side of the upper guide member main body 39, the height position from the document P of the CIS 10 is shown in FIG. 9, the upper frame 26 is opened, and the intermediate second frame 28 is rotated with the fixed shaft 30 as a fulcrum, so that the height of the upper guide member body 39 can be increased from the bottom surface 39 a side using a driver or the like (not shown). The height adjusting screw 44 can be turned. Therefore, the position of the CIS 10 can be easily adjusted without removing the intermediate second frame 28 from the image reading apparatus 1 and disassembling it, so that the labor and time required for the adjustment work can be reduced. is there.

  As shown in FIGS. 2 and 3, the pressing roller 23 is provided with a roller shaft 23a whose both ends are rotatably supported by the upper guide member main body 39, and a predetermined interval in the axial direction of the roller shaft 23a. And a roller body 23b provided so as to partially protrude from a square hole 54 formed through the bottom 37 of the upper guide member body 39. As shown in FIG. 1, a coil spring 55 is disposed between the roller bodies 23b of the pressing roller 23 so as to urge the roller shaft 23a downward. The other end of the coil spring 55 is It is attached to the upper lid member 33. Accordingly, the pressure roller 23 is configured such that its roller body 23 b is pressed against the discharge roller 22 and is rotated by the rotation of the discharge roller 22. As a result, the document P conveyed on the conveyance path 9 is nipped by the discharge roller 22 and the pressing roller 23 and conveyed downstream.

  In the image reading apparatus 1, in order to perform good image reading by the CIS 10, the CIS main body 49 is located immediately above the position where the document P is in contact with the reading glass 20, that is, directly above the position where the platen roller 21 and the reading glass 20 are in contact. It is necessary to arrange a reading area (not shown). Therefore, in the image reading apparatus 1, as shown in FIG. 5, the positioning members 43 having the vertical portions 41 formed with the U-shaped grooves 41a are attached to both ends of the CIS main body 49, and the vertical portions 41 are inserted into the insertion holes. The CIS 10 can be moved in the document conveying direction with respect to the upper guide member main body 39 by being inserted into the main guide member 46. As a result, the CIS 10 moves so as to fit the U-shaped groove 41a to the roller shaft 21a of the platen roller 21 when the intermediate second frame 28 is attached to the image reading apparatus 1, and so on. Therefore, good image reading by the CIS 10 can be performed.

  The present invention can be configured not only to read both sides of a document with a movable reading means and a contact image sensor, but also to read only one side of a document with a contact image sensor.

1 is a schematic longitudinal sectional view showing a configuration of an image reading apparatus 1 according to an embodiment of the present invention. FIG. 4 is a schematic perspective view showing a configuration of an upper guide member 32. FIG. 4 is a schematic bottom view showing the configuration of the upper guide member 32. The figure which shows the AA cross section in FIG. The disassembled perspective view which shows the attachment structure of CIS10. The disassembled perspective view which shows the structure of CIS10. The schematic perspective view which shows the structure of the positioning member (receiving member) 43. FIG. FIG. 4 is a schematic bottom view showing the configuration of a positioning member (receiving member) 43. 3 is a schematic longitudinal sectional view showing a state in which an upper frame 26 and an intermediate second frame 28 are opened in the image reading apparatus 1. FIG. FIG. 6 is a schematic longitudinal sectional view showing an image reading unit 70 in an image reading apparatus according to a conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image reader 9 Conveyance path 10 Contact type image sensor (CIS)
37 Bottom (upper guide body)
39 Upper guide member body 39a Bottom surface (upper guide member body)
40a Receiving surface 43 Receiving member (positioning member)
44 Height adjusting screw 44a Screw part 45 Reading means support part 48 Screw hole P Document

Claims (3)

Of the pair of upper and lower guide members forming the most downstream portion of the transport path, a reading means support portion having screw holes formed on the upper surface at both ends in the document width direction at the bottom of the upper guide member main body disposed on the upper side. Protruding,
Receiving members each having a receiving surface for receiving the reading means supporting portion are attached to both ends, and a contact image sensor that reads one surface of the document conveyed on the conveying path reads each receiving surface to each reading surface. It is placed so as to be able to contact and separate on the means support part,
An image reading characterized in that a height adjusting screw for adjusting the height position of the contact image sensor from the original is screwed into the screw hole so as to be able to protrude and retract from the upper surface of the reading means supporting portion. apparatus.   The upper guide member main body is attached so as to be openable and closable so as to expose the most downstream part of the transport path, and the screw hole is formed to reach the bottom surface of the upper guide member main body, and the height adjustment is performed. The image reading apparatus according to claim 1, wherein a screw is screwed into the screw hole from a bottom surface side of the upper guide member main body.   The image reading apparatus according to claim 1, wherein the most downstream portion of the conveyance path is formed horizontally.

Images