Image reading device

Abstract

To provide an image scanning device that makes it easy to remove documents ejected into the output tray. [Solution] The image reading device comprises a document transport unit having a paper feed tray and an output tray positioned below the paper feed tray, and an image reading unit that moves a reading sensor 61 to a reading position and a home position where image reading operations are possible. The image reading device comprises a movable tray 73 that is movably supported on the output tray and moves in the output direction of the document, thereby moving the output document in the output direction, and an interlocking mechanism 75 that moves the movable tray 81 to a close position closest to the output port in conjunction with the movement of the reading sensor 61 from the home position to the reading position, and moves the movable tray 73 to a distanced position further from the output port than the close position in conjunction with the movement of the reading sensor 61 from the reading position to the home position after the reading operation is completed.

Description

Technical Field

[0001] The present invention relates to an image reading apparatus including a document conveyance unit in which a discharge tray is disposed below a paper feed tray.

Background Art

[0002] An image reading apparatus that conveys a document and reads an image of the document includes a document conveyance unit that conveys the document and an image reading unit that reads an image of the document. The document conveyance unit includes a paper feed tray on which the document is placed, a horizontal U-shaped conveyance path through which the document placed on the paper feed tray is conveyed from a paper feed port toward a discharge port, and a discharge tray that is disposed below the paper feed tray and on which the document discharged from the discharge port is placed.

[0003] With such a document conveyance unit, as the size is reduced (particularly in the height direction), the distance between the paper feed tray and the discharge tray has become narrower. As an example, the minimum distance is 16 mm. When the distance between the two trays becomes narrow in this way, there is a problem that it is difficult to take out the document discharged onto the discharge tray. Particularly in the case of a small-sized document, it is necessary to deeply insert a hand between the paper feed tray and the discharge tray, making it even more difficult to take out.

[0004] Therefore, Patent Document 1 discloses a document conveyance unit in which a document table (corresponding to a paper feed tray) is supported so as to be rotatable upward about an end portion on the side opposite to a conveyance unit (corresponding to a conveyance path). By rotating the document table upward, the space above the discharge tray is opened, making it easier to take out the document discharged onto the discharge tray.

[0005] Further, Patent Document 2 discloses an image reading apparatus including a document moving mechanism that moves a discharged document in a direction intersecting the discharge direction when the width of the document is less than a predetermined width.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2017-077939 [Patent Document 2] Japanese Patent Publication No. 2024-001528 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] However, the document transport unit described in Patent Document 1 above has the problem of poor workability because the paper feed tray is rotated manually. Furthermore, since space must be secured for the paper feed tray to rotate, there is also the problem that the installation location of the image reading device is limited.

[0008] Furthermore, the aforementioned problem of difficulty in removing documents due to the gap between the paper feed tray and the output tray occurs regardless of the size (width) of the document. Therefore, measures that only consider the width of the document, as in Patent Document 2, will not resolve this problem.

[0009] In consideration of the above circumstances, the present invention aims to provide an image reading device that facilitates the removal of documents discharged into the output tray. [Means for solving the problem]

[0010] To solve the above problems, the present invention provides an image reading device comprising: a document transport unit comprising: a transport path through which a document is transported from a paper feed opening to an output opening located below the paper feed opening; a paper feed tray having a fixed end supported below the paper feed opening and a free end opposite the fixed end on which a document is placed; and an output tray located below the paper feed tray on which a document discharged from the output opening is placed; a reading sensor for reading an image of a document; and a sensor movement mechanism for moving the reading sensor to a reading position where the reading operation of the image of the document transported by the document transport unit is possible and to a home position to which it is returned after the reading operation is completed; An image reading device comprising: a movable tray supported on the output tray so as to be movable along the output direction of the document and the opposite direction thereof, and which moves in the output direction to move the document output from the output port in the output direction; and an interlocking mechanism which moves the movable tray to a close position closest to the output port in conjunction with the movement of the reading sensor from the home position to the reading position by the sensor movement mechanism, and moves the movable tray to a distanced position further from the output port than the close position in conjunction with the movement of the reading sensor from the reading position to the home position by the sensor movement mechanism after the reading operation is completed.

[0011] In the present invention, the leading edge position of the document in the discharge direction when the movable tray moves to the separated position may be closer to the free end of the paper feed tray than the leading edge position of the document in the discharge direction when the movable tray moves to the approached position.

[0012] In the present invention, the interlocking mechanism may be characterized in that when the reading sensor moves from the home position to the reading position by the sensor movement mechanism, the tray-side pinion gear rotates in one direction via the sensor-side pinion gear to move the movable tray to the approach position, and when the reading sensor moves from the reading position to the home position by the sensor movement mechanism, the tray-side pinion gear rotates in the opposite direction via the sensor-side pinion gear to move the movable tray to the distance position.

[0013] In the present invention, the top plate of the image reading unit has an opening that exposes the sensor-side pinion gear, and the image reading unit has a partition wall that separates the movement space of the sensor-side rack gear, which includes the opening, from the movement space of the reading sensor, and the partition wall is characterized in that a slit is formed through which the holder passes when the reading sensor moves.

[0014] In the present invention, the reading unit includes a contact glass on which a document is placed, the sensor movement mechanism moves the reading sensor to a reading start position and a reading end position of the document placed on the contact glass, and when the reading sensor moves from the contact glass to the reading start position by the sensor movement mechanism, the sensor-side rack gear separates from the sensor-side pinion gear. [Effects of the Invention]

[0015] According to the present invention, after the image scanning and feeding operation is completed, the document placed on the output tray can be automatically moved to a position far from the output opening, so that the output document can be removed without having to reach deeply into the gap between the paper feed tray and the output tray.

Brief Description of the Drawings

[0016] [Figure 1] It is a perspective view showing an image reading apparatus according to an embodiment of the present invention. [Figure 2] It is a cross-sectional view showing an image reading apparatus according to an embodiment of the present invention. [Figure 3] It is a view showing a document detection unit in an image reading apparatus according to an embodiment of the present invention. [Figure 4] It is a perspective view showing a document moving mechanism in an image reading apparatus according to an embodiment of the present invention. [Figure 5] It is a perspective view showing a movable tray supported by a conveyance unit in an image reading apparatus according to an embodiment of the present invention. [Figure 6] It is a cross-sectional view showing an interlocking mechanism of a document moving mechanism in an image reading apparatus according to an embodiment of the present invention. [Figure 7] It is a cross-sectional view showing a pinion gear and a pin of an interlocking mechanism in an image reading apparatus according to an embodiment of the present invention. [Figure 8] It is a view schematically showing a document moving mechanism in an initial state in an image reading apparatus according to an embodiment of the present invention. [Figure 9] It is a view schematically showing a document moving mechanism during an image reading operation (document conveyance method) in an image reading apparatus according to an embodiment of the present invention. [Figure 10] It is a view schematically showing a document moving mechanism after the completion of an image reading operation (document conveyance method) in an image reading apparatus according to an embodiment of the present invention. [Figure 11] It is a view schematically showing a document moving mechanism at the start of an image reading operation (document fixing method) in an image reading apparatus according to an embodiment of the present invention.

[0017] Hereinafter, an image reading apparatus according to an embodiment of the present invention will be described with reference to the drawings.

[0018] First, the overall configuration of the image reading device 1 will be described with reference to Figures 1 and 2. Figure 1 is a perspective view of the image reading device 1, and Figure 2 is a cross-sectional view of the image reading device 1. Fr, Rr, L, and R shown in each figure indicate the front, back, left, and right sides of the image reading device 1, respectively.

[0019] The image reading device 1 comprises a document transport unit 3 and an image reading unit 5 positioned below the document transport unit 3. The document transport unit 3 is rotatably connected to the image reading unit 5 in the vertical direction. More specifically, the left and right lower corners of the document transport unit 3 are rotatably connected to the left and right upper corners of the image reading unit 5. The image reading device 1 performs the image reading operation of a document by means of a document transport method and a document fixing method, as will be described later.

[0020] First, the document transport unit 3 will be explained, mainly with reference to Figure 2. As shown in Figure 1, the document transport unit 3 comprises a transport section 11, a paper feed tray 13, and an output tray 15.

[0021] First, let's describe the transport unit 11. A paper feed opening 21 and an output opening 23 are formed on the right side of the transport unit 11. The output opening 23 is located below the paper feed opening 21. Furthermore, the transport unit 11 has a horizontal U-shaped transport path 25 that runs from the paper feed opening 21 to the output opening 23. The direction in which the document is transported along the transport path 25 is called the transport direction. An opening is formed at the left end of the bottom surface of the transport unit 11, along the width direction of the document. A transparent glass plate 27 is fitted into the opening. A reading sensor 29 is positioned above the glass plate 27. When the document is transported below the glass plate 27, the reading sensor 29 reads the image from one side (the back side) of the document. A predetermined position below the glass plate 27 is called the reading position P0.

[0022] The transport path 25 is equipped with, in order from the upstream side in the transport direction, a pickup roller (not shown), a paper feed roller 31, a separation pad 33, a first transport roller pair 35, a second transport roller pair 37, and a discharge roller pair 39.

[0023] The pickup roller is rotatably supported by a holder (not shown) above the transport path 25. The holder is rotatably supported by a drive shaft 41 located downstream of the pickup roller in the transport direction, and is capable of swinging vertically. The paper feed roller 31 is rotatably supported by the drive shaft 41 above the transport path 25. The separation pad 33 is pressed against the paper feed roller 31 across the transport path 25. This forms a separation nip between the paper feed roller 31 and the separation pad 33.

[0024] The first transport roller pair 35 comprises a transport roller and a driven roller positioned on either side of the transport path 25. The second transport roller pair 37 is positioned between the first transport roller pair 35 and the reading position P0, and comprises a drive roller and a driven roller positioned on either side of the transport path 25. The discharge roller pair 39 is positioned inside the discharge port 23, and comprises a transport roller and a driven roller positioned on either side of the transport path 25. The drive roller of the discharge roller pair 39 also serves as the drive roller of the first transport roller pair 35.

[0025] Next, the paper feed tray 13 will be described. The paper feed tray 13 is formed in the shape of a rectangular plate, having a fixed end 13a fixed to the transport unit 11 and a free end 13b opposite to the fixed end 13a. The paper feed tray 13 is in a position that is inclined downward from the free end 13b toward the fixed end 13a, with the fixed end 13a supported below the paper feed opening 21 of the transport unit 11.

[0026] Furthermore, the transport unit 11 is equipped with a document detection unit 47 that detects documents placed on the paper feed tray 13. The document detection unit 47 will be described with reference to Figure 3. Figure 3 is a view of the document detection unit 47 from the front. The document detection unit 47 comprises an actuator 51 that is activated by the placed document, and a light sensor 53 whose optical path is formed or blocked by the actuator 51.

[0027] The actuator 51 includes a rotating shaft 51a, an actuator piece 51b extending radially from the rotating shaft 51a, and a light-shielding piece 51c extending radially from the rotating shaft 51a. The actuator piece 51b is positioned in the center of the paper feed tray 13 in the width direction (front-to-back direction), and the light-shielding piece 51c is positioned on the outside of the paper feed tray 13. When the actuator piece 51b is pushed up by the placed document (see arrow in Figure 3), the rotating shaft 51a rotates, and the light-shielding piece 51c rotates around the rotating shaft 51a. When no document is placed in the paper feed tray 13 and the actuator piece 51b hangs down from the rotating shaft 51a (see solid line in Figure 3), an optical path for the light sensor 53 is formed, and the light sensor 53 outputs an off signal. When the actuator piece 51b is pushed up by the placed document, causing the light-shielding piece 51c to rotate (see the dashed line in Figure 3), the optical path of the light sensor 53 is blocked by the light-shielding piece 51c, and the light sensor 53 outputs an ON signal.

[0028] Next, the output tray 15 will be described. As shown in Figures 1 and 2, the output tray 15 is rectangular in shape, extending from below the output port 23 to below the paper feed tray 13, along the direction of document output. The minimum distance between the paper feed tray 13 and the output tray 15 is 16 mm in one example.

[0029] Next, the image reading unit 5 will be described, mainly with reference to Figure 2. The image reading unit 5 includes a contact glass 61 on which the document is placed, a reading sensor 63 for reading the image of the document, and a sensor movement mechanism 65 for moving the reading sensor 63.

[0030] The contact glass 61 is fitted into the top surface of the housing of the image reading unit 5. By rotating the document transport unit 3 upward relative to the image reading unit 5, the contact glass 61 is exposed.

[0031] The reading sensor 63 is, for example, a CIS (contact image sensor) and is housed in a holder 67. The reading sensor 63 housed in the holder 67 is positioned below the contact glass 61, along the width direction (front-to-back direction) of the document.

[0032] The sensor movement mechanism 65 moves the reading sensor 63 (holder 67) to the home position P1, the reading position P2, the reading start position P3, and the reading end position P4. As shown in Figure 2, the home position P1 is to the right of the reading position P0 of the document transport unit 3. The reading position P2 is opposite the reading position P0 of the document transport unit 3 and is a position in the document transport system where the image of one side (front side) of the document transported by the document transport unit can be read.

[0033] The reading start position P3 is to the right of the home position P1, and the reading end position P4 is located to the right of the reading start position P3. As the reading sensor 63 moves from the reading start position P3 to the reading end position P4, the image of the document placed on the contact glass 61 is read in the document fixing method.

[0034] Next, the image reading operation will be briefly explained. In the document transport method, the document is placed on the paper feed tray 13. Then, the holder rotates downward so that the pickup roller contacts the topmost document. After that, the paper feed roller 31 and the pickup roller rotate, and the document placed on the paper feed tray 13 is fed into the separation nip. If only one document is fed, the document is transported through the separation nip. If multiple documents are fed, only the topmost document is separated from the other documents at the separation nip and transported away from the separation nip. The document is transported to the reading position P0 by the first transport roller pair 35 and the second transport roller pair 37. At the reading position P0, the image of one side (the back side) of the document is read by the reading sensor 29. After that, the document is transported by the discharge roller pair 39 and discharged through the discharge port 23 into the discharge tray 15.

[0035] In the document transport system, when reading images on both sides, the reading sensor 63 in the image reading unit 5 is moved from the home position P1 to the reading position P2 by the sensor movement mechanism 65. After that, the document is transported as described above. As the document passes the reading position P0, the image on one side of the document (the back side) is read by the reading sensor 29, and the image on the other side (the front side) is read by the reading sensor 63 of the image reading unit 5.

[0036] In the document-fixing method, the document transport unit 3 is rotated upward to expose the contact glass 61, the document is placed on the contact glass 61, and then the document transport unit 3 is rotated downward to hold the document in place. Subsequently, the reading sensor 63 moves from the home position P1 to the reading start position P3 by the sensor movement mechanism 65, and reads the image while moving from the reading start position P3 to the reading end position P4.

[0037] As mentioned above, in the document transport system, after image scanning is complete, the document is ejected from the output port 23 and placed on the output tray 15. To retrieve this document, it is necessary to reach one's hand into the space between the paper feed tray 13 and the output tray 15. Since the minimum distance between the two trays is about 16 mm, there is a problem in that it is difficult to reach in and grasp the document.

[0038] The image reading device 1 of this embodiment includes a document moving mechanism that moves the document ejected from the ejection port 23 to a position where it is easier to retrieve in the document transport system. This document moving mechanism will be described below.

[0039] The document transfer mechanism 71 will be described with reference to Figure 4. Figure 4 is a perspective view showing the document transfer mechanism 71. The document transfer mechanism 71 comprises a movable tray 73 positioned on the output tray 15 and an interlocking mechanism 75 that links the movement of the reading sensor 63 (holder 67) of the image reading unit 5 to the movement of the movable tray 73.

[0040] First, the movable tray 73 will be described with reference to Figure 5. Figure 5 is a perspective view showing the movable tray 73 supported by the transport unit 11. The movable tray 73 is supported by the transport unit 11 so as to be movable in the discharge direction (right) and the opposite direction (left). The movable tray 73 includes a mounting section 81 positioned on the upper surface of the discharge tray 15 on which the rear end of the document discharged from the discharge port 23 is placed, and a connecting section 83 connected to the interlocking mechanism 75.

[0041] The mounting section 81 has a bottom plate 81a and a rear end plate 81b provided perpendicular to the bottom plate 81a. The bottom plate 81a is formed in a rectangular shape with a width approximately equal to the maximum size of the original document and a predetermined length along the discharge direction. The rear end plate 81b is formed substantially perpendicular to the rear end edge of the bottom plate 81a (the downstream edge in the discharge direction, the left end edge in the figure). The connecting section 83 extends from one side edge of the rear end plate 81b (the rear side edge in the figure) downstream in the discharge direction (to the left in the figure). A tray-side rack gear 85 having downward-facing rack teeth is formed along the upper edge of the connecting section 83.

[0042] Furthermore, as shown in Figure 5, a slit 83a is formed in the connection portion 83 along the longitudinal direction (left-right direction). The leftmost end of the slit 83a (the downstream end in the discharge direction) is formed as a circle with a diameter larger than the height of the slit 83a.

[0043] The connecting portion 83 is supported by the conveying portion 11 so as to be movable in the discharge direction (right) and the opposite direction (left). As shown in Figure 5, a pin 91 protrudes forward from the rear side wall of the conveying portion 11. The pin 91 has a cylindrical head portion 91a and an I-cut portion 91b formed by cutting the cylinder with two upper and lower planes parallel to the axial direction of the cylinder. The outer diameter of the head portion 91a is equivalent to the diameter of the circular left end of the slit 83a formed in the connecting portion 83 of the movable tray 73. The parallel upper and lower planes of the I-cut portion 91b are aligned in the left-right direction. The distance between the parallel upper and lower planes is equivalent to the width (height) of the slit 83a.

[0044] The pin 91 is inserted into the slit 83a of the connector 83. Specifically, when the head portion 91a of the pin 91 is inserted into the left circular end of the slit 83a, the movable tray 73 descends due to its own weight, and the lower I-cut portion 91b contacts the lower edge of the left circular end of the slit 83a. When the movable tray 73 is then moved into the slit 83a, the upper I-cut portion 91b enters the slit 83a, and the connector 83 is guided by the pin 91 in the discharge direction and the opposite direction. Therefore, the movable tray 73 can move in the discharge direction and the opposite direction at a predetermined height position. In addition, the head portion 91a of the pin 91 prevents the movable tray 73 from detaching from the pin 91. Furthermore, the range of movement of the movable tray 73 in the left-right direction is restricted by the pin 91 and the slit 83a.

[0045] Next, the interlocking mechanism 75 will be described with reference to Figures 6 and 7. Figure 6 is a cross-sectional view showing the interlocking mechanism 75, and Figure 7 is a cross-sectional view showing the pin 121 (151) and the pinion gear 103 (105). As shown in Figure 4, the interlocking mechanism 75 includes a sensor-side rack gear 101 integrally provided on the holder 67 of the image reading unit 5, a sensor-side pinion gear 103 that meshes with the sensor-side rack gear 101, and a tray-side pinion gear 105 that meshes with the tray-side rack gear 85 and also meshes with the sensor-side pinion gear 103.

[0046] First, let's describe the sensor-side rack gear 101. The sensor-side rack gear 101 has upward-facing rack teeth and is formed on one side edge of the holder 67 (the rear side edge in Figure 6) so as to be aligned with the discharge direction.

[0047] As shown in Figure 6, the image reading unit 5 has a partition wall 111 that separates the space S1 in which the reading sensor 63 is housed (the space for the movement of the reading sensor 63) from the space S2 in which the sensor-side rack gear 101 is housed (the space for the movement of the sensor-side rack gear 101). The partition wall 111 has a slit 111a through which a part of the holder 67 passes. As described above, when the reading sensor 63 moves to the home position P1, a part of the holder 67 moves within the slit 111a.

[0048] Next, the sensor-side pinion gear 103 will be described. As shown in Figure 6, the sensor-side pinion gear 103 is rotatably supported by a pin 121 provided on the rear wall of the image reading unit 5 and meshes with the sensor-side rack gear 101. The sensor-side pinion gear 103 is exposed through an opening 113 formed in the top plate of the housing of the image reading unit 5.

[0049] As shown in Figure 7, the pin 121 is cylindrical, and a tapered inclined surface 121a is formed at the corner between the tip surface and the outer surface. Furthermore, a groove 123 is formed on the outer surface of the pin 121, spaced at a predetermined distance from the inclined surface and extending in the circumferential direction. On the other hand, the sensor-side pinion gear 103 has a shaft hole 131 into which the pin 121 is fitted. A projection 133 is formed on the inner surface of the shaft hole 131 along the circumferential direction. In the direction Y (left direction in Figure 7) of fitting the sensor-side pinion gear 103 onto the pin 121, the downstream end face 133a of the projection 133 (left side in Figure 7) is inclined so that the diameter of the shaft hole 131 is reduced. The upstream end face 133b of the projection 133 (right side in Figure 7) is formed perpendicular to the inner surface of the shaft hole 131.

[0050] As the sensor-side pinion gear 103 is fitted onto the pin 121 along the direction Y, the downstream end face 133a of the projection 133 of the shaft hole 131 eventually comes into contact with the inclined surface 121a of the pin 121. As the sensor-side pinion gear 103 is further fitted onto the pin 121, the downstream end face 133a of the projection 133 is guided by the inclined surface 121a of the pin 121, causing the sensor-side pinion gear 103 to elastically deform so that the shaft hole 131 expands in diameter. Subsequently, when the projection 133 reaches the groove 123, the sensor-side pinion gear 103 elastically returns to its original position, the shaft hole 131 shrinks in diameter, and the projection 133 engages with the groove 123. In this way, the sensor-side pinion gear 103 is made easier to fit onto the pin 121. In addition, the sensor-side pinion gear 103 is prevented from coming off the pin 121.

[0051] Next, the tray-side pinion gear 105 will be described. As shown in Figure 4, the tray-side pinion gear 105 is a two-stage gear having a large-diameter gear 141 and a small-diameter gear 143. The large-diameter gear 141 and the small-diameter gear 143 are connected via a torque limiter 145. As shown in Figure 6, the tray-side pinion gear 105 is rotatably supported by a pin 151 provided on the rear side wall of the transport section 11 of the document transport unit 3, with the small-diameter gear 143 meshing with the tray-side rack gear 85 and the large-diameter gear 141 meshing with the sensor-side pinion gear 103. The method of supporting the tray-side pinion gear 105 on the pin 151 is the same as the method of supporting the sensor-side pinion gear 103 on the pin 121 described above (see Figure 7).

[0052] The operation of the document transfer mechanism 71 described above will be explained with reference to Figures 8 to 11. Figures 8 to 11 schematically show the document transfer mechanism 71. First, the operation of the document transfer mechanism 71 in the document transport method (when scanning both sides) will be explained with reference to Figures 8 to 10.

[0053] As shown in Figure 8, in the initial state, the mounting portion 81 of the movable tray 73 is positioned downstream of the discharge port 23 in the discharge direction (to the right in the figure). The pin 91 is located near the right end of the slit 83a of the movable tray 73. That is, there is a predetermined gap between the rear end plate 81b of the mounting portion 81 and the discharge port 23. Also, the reading sensor 63 has moved to the home position P1. The leftmost end of the tray-side rack gear 85 is meshed with the small-diameter gear 143 of the tray-side pinion gear 105. The left end of the sensor-side rack gear 101 is meshed with the sensor-side pinion gear 103.

[0054] As shown in Figure 9, when a document is placed on the paper feed tray 13, the output of the optical sensor 53 of the document detection unit 47 (see Figure 3) switches from the off state to the on state, and the reading sensor 63 moves from the home position P1 to the reading position P2 by the sensor movement mechanism 65 (see arrow A1). That is, the sensor-side rack gear 101 moves to the left together with the holder 67. As a result, the sensor-side pinion gear 103 that meshes with the sensor-side rack gear 101 rotates clockwise in the figure (see arrow A2), and the tray-side pinion gear 105 that meshes with the sensor-side pinion gear 103 rotates counterclockwise in the figure (see arrow A3). Consequently, the tray-side rack gear 85 that meshes with the tray-side pinion gear 105 moves to the left in the figure (see arrow A4), and the mounting portion 81 of the movable tray 73 approaches the discharge port 23. Preferably, the rear end plate 81b of the mounting portion 81 of the movable tray 73 moves directly below the discharge port 23. The position of the movable tray 73 at this time is an example of the approach position in the present invention. At this time, the pin 91 is located near the left end of the slit 83a of the movable tray 73.

[0055] Subsequently, the image reading operation is performed. That is, the document is transported as described above, and the image is read by the reading sensors 29 and 63. The document from which the image has been read is ejected from the output port 23. The rear end portion of the document D ejected from the output port 23 falls onto the bottom plate 81a of the mounting section 81 of the movable tray 73. The front end portion of the document D falls into the output tray 15.

[0056] When all the documents placed on the paper tray 13 have been transported, the output of the optical sensor 53 of the document detection unit 47 is switched off. When the image reading operation of the last document is completed and it is ejected from the ejection port 23, the reading sensor 63 moves from the reading position P2 to the home position P1 by the sensor movement mechanism 65, as shown in Figure 10 (see arrow A5). That is, the sensor-side rack gear 101 moves to the right together with the holder 67. Then, the sensor-side pinion gear 103 that meshes with the sensor-side rack gear 101 rotates counterclockwise in the figure (see arrow A6), and the tray-side pinion gear 105 that meshes with the sensor-side pinion gear 103 rotates clockwise in the figure (see arrow A7). Then, the tray-side rack gear 85 that meshes with the tray-side pinion gear 105 moves to the right in the figure (see arrow A8). In other words, the mounting portion 81 of the movable tray 73 moves away from the ejection port 23. The position to which the movable tray 73 moves is an example of a spaced-out position in the present invention.

[0057] As the movable tray 73 moves from the approaching position to the distanced position, the document D that has fallen onto the mounting portion 81 of the movable tray 73 is pushed by the rear end plate 81b of the mounting portion 81 and moves in the discharge direction. In other words, the document D moves towards the free end 13b (see Figure 2) of the paper feed tray 13, and the leading edge of the document D approaches the free end 13b of the paper feed tray 13. As a result, the discharged document D can be removed without having to reach deeply into the gap between the paper feed tray 13 and the discharge tray 15.

[0058] Next, the operation of the document movement mechanism in the document fixing method will be explained with reference to Figure 11. In the initial state, similar to the document transport method, as shown in Figure 8, the mounting portion 81 of the movable tray 73 is positioned slightly downstream from the discharge port 23 in the discharge direction (to the right in the figure). The leftmost end of the tray-side rack gear 85 meshes with the small-diameter gear 143 of the tray-side pinion gear 105. The leftmost end of the sensor-side rack gear 101 meshes with the sensor-side pinion gear 103.

[0059] When the start of the document reading operation is input to the image reading unit 5, the sensor movement mechanism 65 moves the reading sensor 63 from the home position P1 to the reading start position P3, as shown in Figure 11 (see arrow A9). As a result, the sensor-side rack gear 101 separates from the sensor-side pinion gear 103. Therefore, the movable tray 73 hardly moves from its initial position. More specifically, depending on the meshing position between the sensor-side rack gear 101 and the sensor-side pinion gear 103, the sensor-side pinion gear 103 rotates, causing the tray-side rack gear 85, and thus the movable tray 73, to move slightly via the tray-side pinion gear 105.

[0060] As is clear from the above description, according to the present invention, after the image reading and feeding operation is completed, the document placed on the output tray 15 can be automatically moved to a position far from the output port 23, in other words, to a position close to the free end 13b of the paper feed tray 13. Therefore, the output document can be removed without having to reach deeply into the gap between the paper feed tray 13 and the output tray 15.

[0061] In particular, since the movable tray 73 moves from the close position to the far position in conjunction with the movement of the reading sensor 63 returning from the reading position P2 to the home position P1 after the image reading operation is completed, the workability of the document removal operation is not impaired.

[0062] Furthermore, in order to configure the aforementioned interlocking mechanism 75, it is necessary to form an opening 113 (see Figure 6) on the top plate of the image reading unit 5 that exposes the sensor-side pinion gear 103. When such an opening 113 is formed, there is a possibility that foreign matter may enter the inside of the image reading unit 5 through the opening 113. If the foreign matter that enters adheres to the reading sensor 63, image defects may occur. In this embodiment, a partition wall 111 is formed to separate the space S2 including the opening 113 from the movement space S1 of the reading sensor 63, so even if foreign matter enters through the opening 113, the possibility of the foreign matter adhering to the reading sensor 63 can be reduced.

[0063] Furthermore, in the case of a fixed document method, the image reading operation can be performed with minimal movement of the movable tray 73.

[0064] Furthermore, by adjusting the number of teeth and pitch of each pinion gear 103, 105 and rack gear 85, 101, the movable tray 73 can be moved by the desired distance.

[0065] Furthermore, the large-diameter gear 141 and the small-diameter gear 143 are connected via a torque limiter 145. Therefore, even if an external force acts on the movable tray 73 when the document transport unit 3 is in the open state, causing it to move towards the output port 23, and the right end of the slit 83a comes into contact with the pin 91 while the reading sensor 63 is moving from the home position P1 to the reading position P2, the torque limiter 145 rotates the large-diameter gear 141, allowing the reading sensor 63 to move to the reading position P2.

[0066] In the above embodiment, the mounting portion 81 of the movable tray 73 had a bottom plate 81a and a rear end plate 81b, but the mounting portion 81 may have only a rear end plate 81b. In this case as well, as the movable tray 73 moves from an approaching position to a separated position, the rear edge of the document D loaded on the output tray 15 can be pushed out in the output direction by the rear end plate 81b. In this case, it is preferable to form ribs along the output direction on the output tray 15 and to provide protrusions on the movable tray 73 (rear end plate 81b) that are inserted between adjacent ribs. This ensures that documents that have fallen into the output tray 15 are moved.

[0067] The above-described embodiments of the present invention describe preferred embodiments of the image reading device according to the present invention, and therefore may include various technically preferred limitations. However, the technical scope of the present invention is not limited to these embodiments unless otherwise specified. [Explanation of Symbols]

[0068] 1. Image reading device 3. Document transport unit 5 Image reading unit 13 Paper feed tray 13a fixed end 13b Free end 15 Discharge Tray 21 Paper feed slot 23 Outlet 61 Contact Glass 63 Reading Sensor 65 Sensor movement mechanism 73 Movable tray 75 Interlocking mechanism 85 Tray-side rack gear 101 Sensor-side rack gear 103 Sensor-side pinion gear 105 Tray-side pinion gear 111 Bulkhead 113 Aperture

Claims

1. A document transport unit comprising: a transport path through which documents are transported from a paper feed opening to an output opening located below the paper feed opening; a paper feed tray having a fixed end supported below the paper feed opening and a free end opposite the fixed end, on which documents are placed; and an output tray located below the paper feed tray, on which documents discharged from the output opening are placed; An image reading unit comprising: a reading sensor for reading an image of a document; and a sensor movement mechanism for moving the reading sensor to a reading position where it is possible to read the image of the document being transported by the document transport unit, and to a home position to which it is returned after the reading operation is completed. An image reading device equipped with, A movable tray is supported on the output tray so as to be movable along the output direction of the document and the opposite direction, and moves in the output direction to move the document discharged from the output port in the output direction. An image reading device characterized by comprising: an interlocking mechanism that moves the movable tray to a close position closest to the discharge port in conjunction with the movement of the reading sensor from the home position to the reading position by the sensor movement mechanism; and an interlocking mechanism that moves the movable tray to a distanced position further from the discharge port than the close position in conjunction with the movement of the reading sensor from the reading position to the home position by the sensor movement mechanism after the reading operation is completed.

2. The image reading device according to claim 1, characterized in that the leading edge position of the document in the discharge direction when the movable tray moves to the separated position is closer to the free end of the paper feed tray than the leading edge position of the document in the discharge direction when the movable tray moves to the approached position.

3. The aforementioned interlocking mechanism is A sensor-side rack gear that moves integrally with the reading sensor, The sensor-side pinion gear meshes with the aforementioned sensor-side rack gear, A tray-side rack gear that moves integrally with the aforementioned movable tray, It comprises a tray-side pinion gear that meshes with the tray-side rack gear and also meshes with the sensor-side pinion gear, The image reading device according to claim 1, characterized in that when the reading sensor moves from the home position to the reading position by the sensor moving mechanism, the tray-side pinion gear rotates in one direction via the sensor-side pinion gear to move the movable tray to the approach position, and when the reading sensor moves from the reading position to the home position by the sensor moving mechanism, the tray-side pinion gear rotates in the opposite direction via the sensor-side pinion gear to move the movable tray to the distanced position.

4. The top plate of the image reading unit has an opening that exposes the sensor-side pinion gear. The aforementioned image reading unit is A partition wall separates the movement space of the sensor-side rack gear, which includes the aforementioned opening, from the movement space of the reading sensor. The image reading device according to claim 3, characterized in that the partition wall has a slit through which the holder passes when the reading sensor moves.

5. The reading unit includes a contact glass on which the document is placed, The sensor movement mechanism moves the reading sensor to the reading start position and reading end position of the document placed on the contact glass. The image reading device according to claim 3, characterized in that when the reading sensor moves from the home to the reading start position by the sensor movement mechanism, the sensor-side rack gear separates from the sensor-side pinion gear.

Images