JP6020302B2 - Sheet holding device and image reading device - Google Patents

Description

  The present invention relates to a sheet holding device that holds a sheet, and an image reading device that reads an image while conveying the sheet.

  Conventionally, as a sheet holding device that can be used for an image reading device or the like that reads an image while conveying a sheet, a support member body having a mounting surface that can support the sheet, and an extension for extending the mounting surface The thing provided with the supporting member is proposed. Further, this type of extended support member is provided, for example, so as to be rotatable about an axis that intersects the mounting surface, and is stored in the support member main body and a protruding position protruding from the edge of the support member main body. May be configured to be able to change posture. In that case, in order to maintain the posture of the extended support member, a mechanism for engaging a convex portion protruding from the extended support member in a direction along the axis and a concave portion provided in the support member main body is proposed. (For example, refer to Patent Document 1).

JP-A-5-278868

  However, when the posture of the extended support member is maintained by the engagement between the convex portion and the concave portion, it is necessary to provide a certain amount of clearance (so-called looseness) between the outer peripheral surface of the convex portion and the inner wall surface of the concave portion. The posture of the support member cannot be fixedly held. For this reason, when the posture of the extended support member is held by the engagement between the convex portion and the concave portion, there is a possibility that the extended support member may move to a position that is not assumed in design when the apparatus is tilted.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to fixedly hold the posture of the extended support member in a sheet holding device or an image reading device provided with an extended support member that is rotatably provided on a support member main body and capable of changing its posture. As made.

  The sheet holding device according to the present invention, which has been made to achieve the above object, is provided so as to be rotatable about a support member body having a mounting surface capable of supporting a sheet and an axis intersecting with the mounting surface. The extended support is configured so that the posture thereof can be changed between a first position where a tip portion separated from the axis is close to an edge of the support member body and a second position protruding from the edge of the support member body. A member, a pressed portion provided on the extended support member, and spaced apart from the axis; and pressing the pressed portion, wherein the extended support member is in a third position between the first position and the second position. And a spring having a maximum amount of deformation when it is in the position.

  In the sheet holding device of the present invention configured as described above, since the extension support member includes a spring that has a maximum deformation when the extension support member is in the third position between the first position and the second position, When the extended support member changes its posture from the position toward the first position (or the second position), the extension support member is moved toward the first position (or the second position) in a direction in which the amount of deformation of the spring decreases. A rotating force is generated. On the other hand, when the posture of the extension support member changes from the first position (or the second position) toward the third position, it is necessary to rotate the extension support member against an increase in the amount of deformation of the spring. Therefore, the extension support member is fixedly held at the first position (or the second position). Therefore, in the sheet holding device of the present invention, the posture of the extension support member can be fixedly held at the first position or the second position.

  In the present invention, the support member main body includes a first contact portion with which the extended support member contacts in the first position, and a second contact portion with which the extended support member contacts in the second position. You may prepare. In this case, the first position is set as a position where the extended support member comes into contact with the first contact portion, and the second position is set as a position where the extended support member comes into contact with the second contact portion. Therefore, in that case, the posture of the extended support member can be more accurately held at the preset first position or second position.

  Further, in the present invention, the pressed part is spaced apart from the tip part in the opposite direction across the axis, and the distance from the axis to the pressed part is from the axis to the tip part. It may be smaller than the distance up to. In that case, the configuration of the spring, the pressed portion, and the like for holding the posture of the extended support member fixedly at the first position or the second position is on the side opposite to the moving range of the distal end portion of the extended support member. It can be arranged at a position closer to the axis than the tip. Therefore, the entire sheet holding device can be reduced in size.

  In the present invention, the extending direction of the extended support member at the first position may be parallel to an edge of the support member main body. In this case, when the extension support member is in the first position, the extension direction of the extension support member and the edge of the support member main body are parallel to each other, and the entire sheet holding device can be reduced in size.

  In the present invention, the extended support member may be housed in the support member main body at the first position. In this case, when the extended support member is in the first position, the extended support member is accommodated in the support member main body, and the entire sheet holding device can be reduced in size.

  In particular, when gravity is applied to move the extension support member to the second position when the extension support member is disposed at the first position and the device is cleaned up, the extension support member is designed as a support member main body. Even though it is desired to hide the edge of the extended support member, the extended support member may protrude from the edge. Of course, the problem does not occur if the support member body is designed to be slightly larger so that the extended support member does not protrude from the end edge even if the extension support member moves in the second position direction. It will be a hindrance. On the other hand, in this invention, since the attitude | position of an extended support member can be fixedly hold | maintained in a 1st position, it can suppress favorably that an extended support member protrudes from the edge of a support member main body. .

  In the third position, the line of force applied to the pressed part passes through the axis, and in the first position, the line of force applied to the pressed part deviates from the axis to one side. Through the position, in the second position, the line of action of the force applied to the pressed part may pass through a position shifted from the axis to the other.

  In this case, at the third position, the line of action of the force applied to the pressed portion passes through the axis, so that no force for rotating the extension support member is generated. On the other hand, in the first position, the line of action of the force applied to the pressed part passes through a position shifted to one side from the axis, so that the extension support member is rotated in the direction along the force around the axis. A moving force is generated. Further, in the second position, the line of action of the force applied to the pressed portion passes through a position shifted from the axial center to the other, so that the direction along the force is centered on the axial center, that is, opposite to the first position. A force is generated to rotate the extension support member in the direction of rotation. Therefore, in this case, the configuration of the apparatus can be simplified more favorably.

  In the present invention, the spring may be a long spring that generates a force by bending, and the pressed portion may slide along the spring. In that case, the configuration of the apparatus can be further simplified.

  In the present invention, the second extension support member provided to be rotatable around the second axis spaced from the axis, the extension support member, and the interlock that links the rotation of the second extension support member. May be provided. In this case, in conjunction with the rotation of the extension support member, the second extension support member can be rotated around the second axis that is separated from the axis of the extension support member.

  In this case, the interlocking unit may be a pair of gears that engage with each other about the shaft center and the second shaft center. In that case, the extension support member and the second extension support member can be favorably linked with a simple configuration.

  Further, an image reading apparatus of the present invention made to achieve the above object includes any one of the sheet holding devices, a conveyance unit that conveys a sheet supported on the placement surface, and a conveyance unit that conveys the sheet. And a reading unit for reading the image of the sheet thus obtained.

  In the image reading apparatus of the present invention configured as described above, the sheet supported on the mounting surface of the support member main body can be conveyed by the conveyance unit and the image can be read via the reading unit. Since the posture of the extended support member can be fixedly held at the first position or the second position, the state in which the mounting surface is extended by using the extended support member, or the device in which the extended support member is stored is used. A compact state can be stably maintained.

FIG. 3 is a perspective view illustrating a state where the tray of the image reading apparatus according to the first embodiment is opened. It is a perspective view showing the state which closed the tray of the image reading apparatus. It is the sectional view on the AA line of FIG. It is a top view showing a structure and operation | movement of the extension tray support structure of an image reading apparatus. It is a top view showing the operation | movement of the spring of the extension tray support structure in detail. It is a top view showing the structure and operation | movement of the extension tray support structure of a reference example .

  Next, an embodiment of the present invention will be described with an example. The image reading apparatus 1 of the first embodiment exemplified below reads an image of a document and writes data corresponding to the read image to a storage medium such as a removable memory or via a wired or wireless communication unit. It is a device that sends data to an external storage device such as a personal computer. In the following description, the respective parts of the image reading apparatus 1 will be described using the respective directions of the top, bottom, left, and right, which are also shown in the drawing, in order to facilitate understanding of the relative positional relationship between them.

[Schematic Configuration of First Embodiment]
FIG. 1 is a perspective view illustrating a configuration of the image reading apparatus 1. As shown in FIG. 1, the image reading apparatus 1 includes a first tray 3, a second tray 5, a third tray 7 (an example of a support member main body) as an example of a sheet holding device that holds a sheet such as a document, and an extension. A tray 9 (an example of an extended support member) is provided around the casing 10 constituting the main body of the image reading apparatus 1 so as to be opened and closed.

  The first tray 3 is provided at the rear part of the casing 10, that is, upstream in the sheet conveyance direction, so as to be swingable about a horizontal axis via a hinge (not shown). The second tray 5 is connected to the end of the first tray 3 opposite to the end connected to the housing 10 via a hinge 5A so as to be swingable about a horizontal axis. . Further, the third tray 7 is connected to the end of the second tray 5 opposite to the end connected to the first tray 3 via a hinge 7A so as to be swingable about a horizontal axis. Has been.

  When the first tray 3, the second tray 5, and the third tray 7 are opened in a direction away from the housing 10, the first tray 3, the second tray 5, and the third tray 7, as shown in FIG. Each surface constitutes a series of surfaces as a placement surface for holding a sheet such as a document. A pair of third trays 7 that can swing around a shaft 71 (see FIG. 4) provided at the center in the left-right direction is provided at the end of the third tray 7 opposite to the side connected to the second tray 5. An extension tray 9 is provided. The mounting surface of the third tray 7 can be extended by swinging the extension tray 9. The extension tray 9 is accommodated between the main body 7B and the surface plate 7C constituting the third tray 7. The extension tray 9 includes an operation portion 9B that protrudes vertically from the placement surface, and the surface plate 7C is provided with a notch 7D that exposes the operation portion 9B when the extension tray 9 is stored. As shown in FIG. 4, the operation part 9B is provided at a position corresponding to the notch 7D. Further, the extension tray 9 is provided with a mark 9D indicating the operation unit 9B. The operation portion 9B includes an extension portion 9C that extends from the notch 7D to the shaft 71 side.

  When the extension tray 9 is accommodated in the third tray 7 and the first tray 3, the second tray 5, and the third tray 7 are closed in the direction approaching the housing 10, the first tray 3, as shown in FIG. The tray 3 to the third tray 7 are disposed along the outer surface of the housing 10.

  As shown in FIGS. 1 and 3, the housing 10 includes a second housing 11, a first housing 12, and a pair of side plates 13. The second casing 11 is disposed on the first casing 12 and the pair of side plates 13 are provided with the second casing 11 and the first casing 12 sandwiched from the left and right directions. As shown in FIG. 3, a chute 12 </ b> A that is connected to the opened first tray 3 and serves as a sheet conveyance surface is formed on the upper surface of the first housing 12. A separation roller 15 (an example of a conveyance unit) is exposed from below at the front end of the chute 12A, and the lower surface of the separation pad 21 is in contact with the upper surface of the separation roller 15. When sheets (not shown) such as documents are held on the first tray 3, the second tray 5, and the third tray 7 opened as described above, when the separation roller 15 is driven, the sheets are The sheet is conveyed forward one by one from the sheet in contact with the separation roller 15 through between the separation roller 15 and the separation pad 21. Note that the position of the conveyed sheet in the left-right direction is defined by a pair of guides 3 </ b> B provided on the first tray 3. The pair of guides 3B are interlocked symmetrically with respect to the center in the left-right direction via an interlocking mechanism 3C including a gear and a rack.

  A pair of upper and lower transport rollers 16 are disposed in front of the separation roller 15 inside the housing 10. A pair of upper and lower paper discharge rollers 17 are disposed at the front ends of the second housing 11 and the first housing 12. The sheet conveyed forward by the separation roller 15 is conveyed toward the paper discharge roller 17 through the conveyance roller 16, and is discharged to the outside of the housing 10 through the paper discharge roller 17. A pair of CIS (Contact Image Sensor) units 18 and 19 (an example of a reading unit) are provided above and below the sheet conveyance path from the conveyance roller 16 to the paper discharge roller 17 to read the image of the sheet from both above and below. ing. For this reason, the sheet | seat hold | maintained on the surface of the 1st tray 3-the extension tray 9 can be conveyed by the separation roller 15 grade | etc., And an image can be read via the CIS units 18 and 19.

  As shown in FIG. 1, a display device 11 </ b> B that displays information is provided in the center of the upper surface 11 </ b> A of the second housing 11. Further, the display device 11B includes a touch panel that can be input by operation. The upper surface 11A and the display device 11B are slightly inclined forward rather than upward in the vertical direction. Therefore, the visibility and operability from the front of the image reading apparatus 1 can be improved. As shown in FIG. 2, when the first tray 3, the second tray 5, and the third tray 7 are closed, the opening 5B formed at the center of the second tray 5 is superimposed on the display device 11B. Therefore, even when the first tray 3, the second tray 5, and the third tray 7 are closed, the display device 11B exposed through the opening 5B can be viewed and operated.

[Extension tray support structure]
The third tray 7 includes a main body 7B integrally formed with a hinge 7A, and a surface plate 7C that is an example of a placement surface attached to the side of the main body 7B that holds a sheet. The main body 7B supports the extension tray 9 by the following mechanism.

  FIG. 4 is a view of the main body 7B from which the surface plate 7C is removed as viewed from the surface plate 7C side. As shown in FIG. 4, a pair of shafts 71 are provided at the center in the left-right direction of the main body 7 </ b> B, spaced apart in the left-right direction and perpendicular to the surface plate 7 </ b> C. A pair of extension trays 9 are rotatably provided on the pair of shafts 71. Therefore, the third tray 7 and the extension tray 9 form a series of surfaces in parallel. Gears 91 that mesh with each other are formed at opposing portions of the extension trays 9, and the rotation of the extension trays 9 is interlocked by the meshing of the gears 91. That is, as shown in FIG. 4 (A), the leading end portions 9A of the extension trays 9 are separated from each other and overlap the main body 7B, and the leading end portions 9A are close to each other as shown in FIG. 4 (C). Thus, both rotate in a symmetrical phase between the second position protruding from the edge of the main body 7B.

  That is, the gear 91 corresponds to the interlocking portion. When one extension tray 9 is an extension support member, the other extension tray 9 is a second extension support member and the axis of one shaft 71 is an axis. The axis of the other shaft 71 corresponds to the second axis.

  Further, the main body 7B has a pair of spring receivers on the front side (downstream side in the sheet conveying direction) with respect to the extension trays 9 disposed at the first position and on the outer side in the left-right direction with respect to the pair of shafts 71. 73 is formed. A pair of spring receivers 74 is formed at positions on the front side (downstream side in the sheet conveying direction) outside the pair of spring receivers 73 in the left-right direction. Further, a pair of spring receivers 75 are formed at positions on the outer side in the left-right direction than the pair of spring receivers 74 and on the rear side (upstream side in the sheet conveying direction). And the spring 77 which consists of a elongate wire spring is attached so that it may be pinched | interposed from the both sides of a sheet conveyance direction by these spring receivers 74-75.

  A pressed portion 92 is integrally formed on each extension tray 9 at a position opposite to the tip end portion 9 </ b> A across the shaft 71 and facing the spring 77. Although not shown, each pressed portion 92 is formed with a groove that engages with the spring 77 and slides along the spring 77, and the spring 77 is formed in the pressed portion 92 as shown in FIG. I bite in a little.

  Here, as shown in FIG. 4B, when each extension tray 9 is disposed at a predetermined third position between the first position and the second position, the spring 77 is placed on each extension tray 9. No rotational force in the direction of. However, when the tip 9A is separated from the third position even slightly, the spring 77 applies a rotational force toward the first position to each extension tray 9, and the tip 9A comes closer to the third position even slightly. When matched, the spring 77 applies a rotational force to each extension tray 9 toward the second position. Therefore, the main body 7B is integrally formed with a pair of first abutting portions 78 that abut against the extension trays 9 disposed at the first position and lock the extension trays 9 from the front side. Further, the main body 7B has a pair of second abutments that abut each of the extension trays 9 disposed at the second position at the center of the rear edge and lock the extension trays 9 from the center in the left-right direction. The part 79 is also integrally formed.

[Effect of the first embodiment]
5A, 5B, and 5C are plan views showing in detail the operation of the spring 77 corresponding to FIGS. 4A, 4B, and 4C. As shown in FIG. 5B, when each extension tray 9 is disposed at the third position, the line of action of the force F ₁ applied from the spring 77 to the pressed portion 92 passes through the axis of the shaft 71. The spring 77 does not apply a rotational force in either direction to each extension tray 9. At this time, the deformation amount of the spring 77 is maximized.

As shown in FIG. 5A, when each extension tray 9 is disposed at the first position, the line of action of the force F ₁ applied to the pressed portion 92 from the spring 77 is from the axis of the shaft 71 to the main body 7B. It passes through a position shifted to the center in the left-right direction. For this reason, the force F ₁ is decomposed into a force F ₂ directed toward the axial center and a force F ₃ urging the extension tray 9 toward the first position, and the extension tray 9 is indicated by a thick arrow. A rotational moment is applied. As shown in FIG. 5C, when each extension tray 9 is disposed at the second position, the line of action of the force F ₁ applied from the spring 77 to the pressed portion 92 is from the axis of the shaft 71 to the main body 7B. It passes through a position shifted to the outside in the left-right direction. For this reason, the force F ₁ is decomposed into a force F ₂ directed toward the axial center and a force F ₃ urging the extension tray 9 toward the third position, and the extension tray 9 is indicated by a thick arrow. A large rotational moment is applied. In FIG. 5, the force is illustrated only for the left extension tray 9, but the same force also acts on the right extension tray 9.

  That is, in this embodiment, the same principle as that of the crank is used, in which the pressing force by the spring 77 is converted into the rotational force of the extension tray 9. The third position corresponds to the dead center of the crank.

  Thus, the amount of deformation of the spring 77 is maximized when the extension tray 9 is in the third position between the first position and the second position, so that the spring 77 is changed from the third position to the first position (or the second position). When the orientation of the extension tray 9 changes toward, a force for rotating the extension tray 9 in the direction in which the amount of deformation of the spring 77 decreases, that is, the first position (or the second position) is generated. On the other hand, when the posture of the extension tray 9 changes from the first position (or the second position) toward the third position, it is necessary to rotate the extension tray 9 against an increase in the amount of deformation of the spring 77. Therefore, the extension tray 9 is fixedly held at the first position (or the second position).

  Therefore, in the image reading apparatus 1, it is possible to stably maintain a state in which the sheet placement surface is extended using the extension tray 9 or a state in which the extension tray 9 is stored and the apparatus is made compact. In addition, when the extension tray 9 is disposed at the first position or the second position, the extension tray 9 contacts the first contact portion 78 or the second contact portion 79. Therefore, the extension tray 9 is pressed against the first contact portion 78 or the second contact portion 79 by the pressing force of the spring 77, and the posture of the extension tray 9 is more accurately set to the preset first position or second position. Can be held in. In particular, in this embodiment, when the extension tray 9 is disposed at the first position and the first tray 3 to the third tray 7 are closed as shown in FIG. 2, the extension tray 9 is moved to the second position. Gravity acts on. On the other hand, in this embodiment, since the posture of the extension tray 9 can be fixedly held at the first position by the spring 77, it is possible to satisfactorily suppress the extension tray 9 from protruding from the edge of the main body 7B. be able to.

  Further, the pressed portion 92 of the extension tray 9 is separated in the opposite direction to the tip portion 9A across the shaft 71, and the distance L1 from the shaft 71 to the pressed portion 92 is from the shaft 71 to the tip portion 9A. It is smaller than the distance L2. For this reason, the configuration for holding the posture of the extension tray 9 fixedly at the first position or the second position is on the side opposite to the moving range of the tip portion 9A and closer to the shaft 71 than the tip portion 9A. It can be arranged. Therefore, the image reading apparatus 1 can be reduced in size favorably.

  Further, the distance L1 from the shaft 71 to the pressed portion 92 is smaller than the distance L3 from the shaft 71 to the operation portion 9B. For this reason, the operation of moving the posture of the extension tray 9 to the first position or the second position can be performed with a light force. Therefore, the operability of the image reading apparatus 1 can be improved. Further, the operation portion 9B includes the extension portion 9C, so that the sheet can be stably held.

  Furthermore, in the first position, the extending direction of the extension tray 9 is parallel to the rear end edge of the main body 7B, and the extension tray 9 overlaps the main body 7B and is stored in the third tray 7. For this reason, the image reading apparatus 1 when the extension tray 9 is disposed at the first position can be further miniaturized. Further, since the pair of extension trays 9 are interlocked via the gear 91 and individually receive a force from the spring 77, the pair of extension trays 9 can be more reliably held at the first position or the second position. Can do.

[ Reference example ]
In addition, this invention is not limited to the said embodiment at all, It can implement with a various form in the range which does not deviate from the summary of this invention. FIG. 6 is a plan view showing the configuration and operation of the extension tray support structure of the reference example not included in the scope of the present invention .

As shown in FIG. 6, in this reference example , a pair of shafts 71, a first contact portion 78 (not shown in FIG. 6), and a second contact portion 79 are formed on the surface of the main body 107B. Has been. On a pair of extension trays 109 rotatably provided on a pair of shafts 71, a pair of long members 192 that are swingably connected to each other via pins 191 slide in the longitudinal direction as follows. It is provided as possible.

  That is, at the base end portion of each extension tray 109, a rectangular notch 195 (an example of a pressed portion) that is long along the extension direction of each extension tray 109 at a position shifted backward from the shaft 71 in the first position. ) Are formed. A spring 196 made of a compression coil spring is inserted into each notch 195, and each elongate member 192 is inserted into each notch 195 so that it can slide along the notch 195 while compressing it. Each extension tray 109 has a contact surface 199 that contacts each other as shown in FIG. 6C when disposed in the second position.

In this reference example , the pair of extension trays 109 are individually slidably provided in the notches 195 of each extension tray 109 in the longitudinal direction, and swing from each other via pins 191 at the portions protruding from each extension tray 109. They are connected via a pair of long members 192 that are connected to each other. For this reason, the pair of long members 192 function as links, and when one of the extension trays 109 is disposed at the first position as shown in FIG. Arranged in position. As shown in FIG. 6C, when one of the extension trays 109 is disposed at the second position, the other extension tray 109 is also disposed at the second position.

  That is, the long member 192 and the pin 191 correspond to an interlocking portion. When one extension tray 109 is used as an extension support member, the other extension tray 109 serves as the second extension support member, and the axis of the one shaft 71 is aligned. When the shaft center is used, the shaft center of the other shaft 71 corresponds to the second shaft center.

Further, each long member 192 is biased by a pair of springs 196 in a direction protruding from each extension tray 109. Therefore, the direction in which the force applied to each extension tray 109 from each long member 192 and each spring 196 applies a rotational force to each extension tray 109 is shown in FIG. 6C as the extension tray 109 rotates. Thus, the spring 196 is switched at the third position where the deformation amount becomes the maximum. That is, the spring 196 is most compressed in the third position. For this reason, also in this reference example , the extension tray 109 can be fixedly held at the first position or the second position.

More specifically, as shown in FIG. 6A, when each extension tray 109 is disposed at the first position, the urging force F ₁ applied from the right spring 196 to the pin 191 and the left spring 196 to the pin 191 The urging force F ₂ applied to 191 acts in the opposite direction in the left-right direction with the same magnitude. For this reason, the pin 191 does not move. On the right side of the extension tray 109 acts resultant force of the reaction force and the biasing force F ₂ of the urging force F _1, the left side of the extension tray 109, the reaction force and the urging force F ₁ of the biasing force F ₂ The resultant force acts. These resultant forces are applied outward in the left-right direction with respect to each extension tray 109 at the rear of the shaft 71. For this reason, a rotation moment is applied to each extension tray 109, as indicated by the thick arrow, toward the first position.

In the third position shown in FIG. 6B, with respect to the right extension tray 109, the reaction force F ₁ of the urging force applied from the right spring 196 to the pin 191 and the urging force F ₂ applied from the left spring 196 to the pin 191. The resultant force F ₃ acts. At this position, the magnitude of the force is F ₁ = F ₂ , and the line of action of the resultant force F ₃ passes through the axis of the shaft 71. Since the same consideration can be made for the left extension tray 109, each spring 196 does not apply a rotational force in either direction to each extension tray 109. That is, in this state, the rotational moments applied by the springs 196 to any one of the extension trays 109 are balanced with the same magnitude in opposite directions. At this time, the amount of deformation of each spring 196 is maximized.

In the second position shown in FIG. 6C, with respect to the right extension tray 109, the reaction force F ₁ of the urging force applied from the right spring 196 to the pin 191 and the urging force F ₂ applied from the left spring 196 to the pin 191. The line of action of the resultant force F ₃ is shifted forward from the axis of the shaft 71. The resultant force F ₃ acts outward in the left-right direction with respect to the right extension tray 109, and the same applies to the left extension tray 109, so each extension tray 109 is directed to the second position as indicated by the thick arrow. A rotational moment is applied.

Therefore, also in this reference example , the extension tray 109 is fixedly held at the first position or the second position. Therefore, even in the image reading apparatus adopting this reference example , the state in which the sheet mounting surface is extended using the extension tray 109 or the state in which the extension tray 109 is housed to make the apparatus compact is stably maintained. can do.

  Furthermore, in the first embodiment, the spring 77 may be a leaf spring instead of a wire spring, or a resin spring. In each of the above embodiments, a pair of extension trays 9 or 109 are provided as extension support members, but only one extension support member may be provided. For example, in the first embodiment, the pair of gears 91 may be mounted on the shaft 71, and the extension tray 9 may be provided only on one gear 91.

The sheet holding device of the reference example is provided so as to be rotatable about a support member main body having a placement surface capable of supporting the sheet and a pair of axes intersecting the placement surface, and the support member A pair of extended support members configured to change posture between a first position stored in the main body and a second position protruding from an end edge of the support member main body; A pair of elongate members that are individually slidable in the elongate direction on the support member and are connected to each other at portions protruding from the extended support members, and the elongate members are connected to each other. A pair of springs biased in a direction protruding from the extension support member, wherein the first position and the second position are a third position where the amount of deformation of the spring is maximum, that is, the spring is most compressed. It is characterized by being set across the position, Good.

  In the sheet holding device configured as described above, the pair of extension support members are formed in a long shape, and are provided on each extension support member so as to be individually slidable in the longitudinal direction, and project from each extension support member. These portions are connected via a pair of long members that are swingably connected to each other. Therefore, the pair of long members function as links, and when one of the extension support members is arranged at the first position, the other extension support member is also arranged at the first position, and either one of the extension support members is extended. When the support member is disposed at the second position, the other extended support member is also disposed at the second position.

  Each long member is urged by a pair of springs in a direction protruding from each extension support member. For this reason, the direction in which the force applied to each extension support member from each long member and each spring applies the rotational force to each extension support member is the maximum amount of deformation of the spring with the rotation of each extension support member. Switching is made at the three positions, that is, at the position where the spring is most compressed. Therefore, in the sheet holding device, the first position and the second position are set across the third position. For this reason, the extension support member can be fixedly held at the first position or the second position. Furthermore, the sheet holding device of the present invention can be used in various apparatuses such as an image forming apparatus. Further, the shaft 71 is provided perpendicular to the surface plate 7C, which is an example of the sheet placement surface, but may be configured not to be perpendicular. That is, a series of surfaces may be configured in a state where the mounting surfaces of the third tray 7 and the extension tray 9 form an angle. Furthermore, the sheet holding device of the present invention can be used in various apparatuses such as an image forming apparatus.

DESCRIPTION OF SYMBOLS 1 ... Image reading device 3 ... 1st tray 5 ... 2nd tray 7 ... 3rd tray 7B, 107B ... Main body 9,109 ... Extension tray 9A ... End part 15 ... Separation roller 16 ... Conveyance roller 17 ... Discharge roller 18, DESCRIPTION OF SYMBOLS 19 ... CIS unit 71 ... Shafts 77, 196 ... Spring 78 ... 1st contact part 79 ... 2nd contact part 91 ... Gear 92 ... Pressed part 191 ... Pin 192 ... Long member 195 ... Notch 199 ... Contact surface

Claims (8)

A support member body having a mounting surface capable of supporting the sheet;
A pair of axial centers intersecting the placement surface are provided so as to be rotatable about each of the axes, and a distal end portion spaced from the axial center is adjacent to an end edge of the support member main body and the support member main body a pair of extension support member whose attitude changeable configured respectively between a second position projecting from the edge,
A posture in which the pair of extension support members are disposed in the first position and a posture in which the pair of extension support members are disposed in the second position by interlocking the rotation of the pair of extension support members. And an interlocking portion for rotating the pair of extended support members,
Respectively provided on the pair of extended support member, a pair of pressed portions spaced respectively from the axis as the rotational axis of the respective extension support member,
The pair of the pressed portion presses each, a spring deformation amount becomes maximum when the pair of the extension support member is in the third position between the first position and the second position,
A pair of first spring receivers formed on the support member main body at a position farther away from the end edges than the pair of axis centers and in both directions along the end edges than the pair of axis centers; ,
A pair of second springs in the support member main body, which are formed at positions that are farther from the edge than the pair of first spring receivers and outside the pair of shafts in both directions along the edge. And
Equipped with a,
The pair of shaft centers are provided apart in a direction along an edge of the support member body,
The spring is attached to the support member main body by being sandwiched between the pair of first spring receivers and the pair of second spring receivers in a direction approaching and separating from the end edges,
In the first position, the extending direction of the extended support member is parallel to an edge of the support member main body . The support member body, said a first abutment pair of said pair of extension support member abuts respectively in a first position, said second pair of said pair of extension support member in a position to abut the respective second person The sheet holding device according to claim 1, further comprising a contact portion. The pair of pressed parts are spaced apart from each of the tip parts in the opposite direction across the axis, and the distance from the axis to the pressed part is from the axis to the tip part. The sheet holding device according to claim 1, wherein the sheet holding device is smaller than the distance. Wherein the pair of extended support member at the first position, the sheet holding device according to any one of claims 1 to 3, characterized in that accommodated in each of said support member body. In the third position, the line of action of the force applied to each of the pair of pressed parts passes through the respective axis,
In the first position, the line of force applied to each of the pair of pressed parts passes through a position shifted to one side from the respective axis,
In the second position, the sheet holding apparatus according to claim 1 or 4 line of action of the force applied to each of the pair of the pressed portion is characterized in that through the position shifted to the respective axes sincerely other. The said spring is an elongate wire spring which generate | occur | produces force by bending, Comprising: A pair of said to- be-pressed part has a groove | channel which slides along the said spring, respectively , The any one of Claims 1-5 characterized by the above-mentioned. The sheet holding device according to claim 1. The interlocking portion, the sheet holding device according to any one of claims 1 to 6, characterized in that a pair of gears meshing about said pair of axis. A sheet holding device according to any one of claims 1 to 7 ,
A transport unit for transporting a sheet supported on the placement surface;
A reading unit that reads an image of the sheet conveyed by the conveyance unit;
An image reading apparatus comprising:

Images