Paper feeder, and image forming apparatus provided with paper feeder

Abstract

To provide a paper feeder capable of feeding a paper sheet at a predetermined position without skewing, by preventing width restriction members from being moved from an appropriate position according to a width direction length of the paper sheet.SOLUTION: A paper feeder 10 comprises a paper-feed tray 11 on which a sheet S is placed, and a position holding part 20 for holding a position of the sheet S. The position holding part 20 comprises: a pair of width restriction members 21 movably attached to the paper-feed tray 11 in a width direction of the paper-feed tray 11; a pair of racks 22 connected to the width restriction members 21, respectively; a pinion 23 engaged with the racks 22; and rack restriction members 30 for restricting movement of the racks 22 at predetermined positions, respectively. One of the racks 22 comprises a plurality of protrusions 24 provided along a longitudinal direction of the racks 22 on a face on an opposite side of a face on which teeth of the one of the racks 22 are formed. One of the restriction members 30 thereof comprises a first engagement member 31 engaged with each of the protrusions 24 from a width direction outer side of the paper-feed tray 11, that is provided on the paper-feed tray 11.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a paper feeder and an image forming apparatus equipped with the paper feeder. [Background technology]

[0002] Image forming devices such as printers, scanners, facsimiles, copiers, and multifunction peripherals are equipped with document feeders that automatically read multiple original sheets one by one. The document feeder includes a paper feed tray on which the original sheets are placed, and the original sheets placed on the paper feed tray are fed into the document feeder one by one to be read. In such document feeders, the paper feed tray is provided with a pair of width-limiting members that regulate the widthwise position of the original sheets so that the original sheets can be fed in a predetermined position and the original sheets are not fed at an angle. These width-limiting members generally include a pair of racks and pinions that engage with the racks, and are used by moving them so that they abut against both widthwise ends of the original sheets placed on the paper feed tray.

[0003] However, there was a problem that the pair of width regulating members could move due to backlash, etc., caused by the reaction force of the original sheet when it is fed, or by vibrations when the document feeder is operating, when only the rack and pinion are engaged.

[0004] For example, Patent Document 1 discloses a paper feed mechanism for solving the above problem. The paper feed mechanism in Patent Document 1 includes a paper feed table on which original sheets are placed and a positioning device for positioning the original sheets in a predetermined position in the width direction. The positioning device includes a pair of width restriction members that reciprocate in the width direction on the paper feed table, a pair of racks connected to each of the pair of width restriction members, and a pinion meshing with each of the pair of racks. A friction braking member is provided between the pair of racks and the paper feed table to suppress movement of the pair of width restriction members. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-282857 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the paper feeding mechanism of Patent Document 1, although a friction braking member is provided between the paper feeding table and the pair of racks, the movement of the pair of racks is restricted solely by frictional force, so there is a problem in that the force restricting the movement of the racks is not sufficient and there is still a risk that the pair of width restricting members may move.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a paper feeding device and an image forming device equipped with a paper feeding device that can prevent a pair of width regulating members from moving from an appropriate position corresponding to the width length of the sheet, thereby feeding the sheet at a predetermined position without it being slanted. [Means for solving the problem]

[0008] The paper feed device of the present invention includes a paper feed tray and a position maintaining unit. Sheets are placed in the paper feed tray. The position maintaining unit maintains the position of the sheets placed in the paper feed tray. The position maintaining unit includes a pair of width restricting members attached to the paper feed tray so as to be movable in the width direction of the paper feed tray, a pair of racks connected to each of the pair of width restricting members, a pinion engaging with the pair of racks, and a rack restricting member that restricts movement of the rack at a predetermined position. One of the pair of racks has a protrusion on a surface opposite to the surface on which the rack teeth are formed. The rack restricting member is provided on the paper feed tray and has a first engaging member that engages with the protrusion from the outer side in the width direction of the paper feed tray. A plurality of protrusions are provided along the longitudinal direction of the rack for each sheet size so that the pair of width restricting members engage with the first engaging member at a position corresponding to the width of a sheet of a predetermined size. The first engaging member is configured to be elastically deformable in a direction perpendicular to the width direction of the paper feed tray when a force equal to or greater than a predetermined value is applied.

[0009] An image forming apparatus according to the present invention includes the paper feeder described above. [Effects of the Invention]

[0010] According to the paper feeding device and the image forming device equipped with the paper feeding device of the present invention, a pair of width regulating members can be prevented from moving from an appropriate position corresponding to the width length of the sheet, so that the sheet can be fed at a predetermined position without being skewed. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing an image forming apparatus including a paper feeder according to an embodiment of the present invention; [Figure 2] 2 is a diagram showing an example of the internal configuration of the paper feeder of FIG. 1. [Figure 3] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 4] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 5] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 6] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 7] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 8] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 9] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 10] FIG. 2 is a plan view of the paper feeder of FIG. [Figure 11] FIG. 10 is a plan view showing another embodiment of the paper feeder of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters and description thereof will not be repeated.

[0013] First, an image forming apparatus 1 and a paper feeder 10 will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of the image forming apparatus 1 equipped with the paper feeder 10 according to this embodiment. FIG. 2 is a diagram showing an example of the internal configuration of the paper feeder 10 according to this embodiment. Note that in FIGS. 1 and 2, a pair of width restriction members 21 are shown in a simplified form. In the following, the up-down direction is defined as the vertical direction when the image forming apparatus 1 is installed in a state in which it is generally used, as shown in FIG. 1, and the front-rear direction is defined as the side on which a user generally stands, with the front being the side. The direction perpendicular to the up-down direction and the front-rear direction is defined as the left-right direction.

[0014] The image forming apparatus 1 is, for example, a printer, scanner, facsimile, copier, or multifunction device. The image forming apparatus 1 is an apparatus that reads an image on an original sheet S to form an electronic image, or that forms an image of the original sheet S or an electronic image on the sheet S. Here, an electronic image means an digitized image that can be displayed on an electronic device such as a computer or a smartphone. The image forming apparatus 1 is equipped with a paper feeder 10.

[0015] The paper feeder 10 is a device that feeds sheets S into the image forming apparatus 1. As shown in Fig. 2, the paper feeder 10 is configured to include a paper feed tray 11 on which sheets S are placed, and a feed unit 13 that feeds the sheets S placed on the paper feed tray 11 to a transport path 12. As shown in Fig. 1, the paper feeder 10 is provided in the image forming apparatus 1 as a device that supplies sheets S, which are originals, to a document feeder 3 provided on the top of the housing 2 of the image forming apparatus 1, or as a device that supplies sheets S used when forming an image inside the image forming apparatus 1 to a manual feed tray 4 provided on the side of the housing 2 of the image forming apparatus 1.

[0016] In the following, the present embodiment will be described using a paper feeding device 10 that is applied to the document feeder 3. The paper feeding device 10 of the present invention can also be applied to the manual feed tray 4 of the image forming apparatus 1.

[0017] Next, the sheet feeding device 10 of this embodiment will be described with reference to Figures 3 to 5. Figures 3 to 5 are plan views of the sheet feeding device 10 of this embodiment. Figure 3 shows a state in which the surface cover 14 is covered, Figure 4 shows a state in which the surface cover 14 has been removed, and Figure 5 shows a state in which the surface cover 14 and rack 22 have been removed. Figure 5 shows an enlarged view of part A in Figure 4. Hereinafter, with the width direction (front-to-back direction) of the sheet feeding tray 11 as the reference, both end sides in the width direction will be referred to as width-direction outer sides or outsides, and the center side in the width direction will be referred to as width-direction inner sides or insides.

[0018] 3 to 5, the sheet feeding device 10 includes a sheet feeding tray 11 on which sheets S (see FIG. 1) are placed, and a position holding unit 20 that holds the position of the sheets S placed on the sheet feeding tray 11. The sheet feeding tray 11 has a similar configuration to a sheet feeding tray provided in any known image forming apparatus 1.

[0019] 4, the position holding unit 20 includes a pair of width restriction members 21 attached to the paper feed tray 11 so as to be movable in the width direction (front-rear direction) of the paper feed tray 11, a pair of racks 22 connected to each of the pair of width restriction members 21, a pinion 23 engaging with the pair of racks 22, and a rack restriction member 30 that restricts movement of the rack 22 at a predetermined position. The pair of width restriction members 21, the pair of racks 22, and the pinion 23 have the same configuration as the width restriction members, racks, and pinions included in the position holding unit 20 provided in any known image forming apparatus 1.

[0020] One of the pair of racks 22 has a protrusion 24 on a surface 22b opposite to a surface 22a on which the teeth of the rack 22 are formed. In this embodiment, the protrusion 24 is formed on the rack 22 located on the front side. The protrusion 24 is formed integrally with the rack 22.

[0021] A plurality of protrusions 24 are provided for each size of sheet S along the longitudinal direction (front-rear direction) of rack 22 at positions where the pair of width restriction members 21 corresponds to the width of a predetermined size of sheet S. The protrusions 24 are provided at positions corresponding to the main sizes of sheet S used in image forming apparatus 1, such as LGL (Leagal), A4, A5, A6, etc.

[0022] Specifically, as will be described later, the rack restricting member 30 has a first engagement member 31 that engages with the protrusion 24 to restrict movement of the rack 22. For example, the protrusion 24 corresponding to an A4-size sheet S is provided so that the protrusion 24 for the A4 size engages with the first engagement member 31 at a position where the opposing inner surfaces 21a of the pair of width restricting members 21 contact both widthwise ends of the A4-size sheet S. In the embodiment of FIG. 4, the innermost protrusion 24 in the width direction of the paper feed tray 11 is for the LGL size, and the protrusions 24 are for the A4 size, A5 size, and A6 size in that order going outwards.

[0023] The rack restricting member 30 restricts the movement of the rack 22 at a predetermined position. As shown in Fig. 5, the rack restricting member 30 has an interlocking member 36, a first engaging member 31, a second engaging member 32, a third engaging member 33, and a fourth engaging member 34 provided on the paper feed tray 11, and a fifth engaging member 35 provided on the interlocking member 36.

[0024] The first engagement members 31 engage with the protrusions 24 from the outside in the width direction of the paper feed tray 11 to restrict movement of the rack 22. The first engagement members 31 are configured to be elastically deformable in a direction perpendicular to the width direction of the paper feed tray 11 (left-right direction) when a user applies a force of a predetermined magnitude or greater to move the pair of width restriction members 21. Specifically, the first engagement members 31 have a rod shape that is approximately L-shaped in a plan view. The first engagement members 31 are disposed near the rack 22 on which the protrusions 24 are provided so that their tip ends can engage with the outer side surfaces (front side surfaces) of the protrusions 24, and their base ends are fixed to the paper feed tray 11. The first engagement members 31 are formed in a rod shape, with their tip ends being free ends and their base ends being fixed ends, and therefore are elastically deformable within a range within which the free ends can move relative to the fixed ends.

[0025] The interlocking member 36 is a member that interlocks the operations of the first engagement member 31 to the fifth engagement member 35 that regulate the movement of the rack 22. The interlocking member 36 has a long side member 361 and a first short side member 362 and a second short side member 363 that are provided at both longitudinal ends of the long side member 361. The long side member 361, the first short side member 362, and the second short side member 363 are rod-shaped, and the interlocking member 36 is generally U-shaped in plan view.

[0026] The interlocking member 36 is arranged such that the longitudinal direction of the long side member 361 is aligned with the short side direction (left-right direction) of the rack 22, the first short side member 362 and the second short side member 363 are positioned on either side of the rack 22 in the short side direction of the rack 22 (see FIG. 4), and the second short side member 363 abuts against the surface of the first engaging member 31 opposite to the rack 22. When the interlocking member 36 is arranged as described above, a recess 364 extending along the longitudinal direction of the long side member 361 is formed on the outer portion of the upper surface of the long side member 361.

[0027] The interlocking member 36 is provided on the sheet feed tray 11 so as to be movable in the longitudinal direction of the rack 22 (front-rear direction) and in the lateral direction of the rack 22 (left-right direction).

[0028] Specifically, the paper feed tray 11 has a first locking member 111, which is a plate-like member that is generally I-shaped in side view, and a second locking member 112, which is a plate-like member that is generally L-shaped in side view, standing upright on the top surface of the paper feed tray 11. In addition, a second locking member 32 is provided at a position facing the first locking member 111 and the second locking member 112. The interlocking member 36 is attached to the paper feed tray 11 by inserting the long side member 361 between the first locking member 111, the second locking member 112, and the second locking member 32. At this time, the base ends of the first locking member 111 and the second locking member 112 abut against the outer side surface (front side surface) of the interlocking member 36, and the tip end of the second locking member 32 abuts against the inner side surface (rear side surface) of the interlocking member 36, as will be described later. As will be described later, the second engagement member 32 is configured to be elastically deformable, and therefore the interlocking member 36 is movable in the longitudinal direction of the rack 22 within the range in which the second engagement member 32 is elastically deformable.

[0029] Additionally, the upper portion of the second locking member 112 protrudes inward (toward the rear), and this protrusion 112a engages with the recess 364 of the interlocking member 36. The protrusion 112a is formed to be smaller in size than the recess 364 in the longitudinal direction (left-right direction) of the long-side member 361. This allows the protrusion 112a to move in the lateral direction of the rack 22 inside the recess 364, and therefore the interlocking member 36 can move in the lateral direction of the rack 22 within the region where the protrusion 112a can move.

[0030] The second engagement member 32 abuts against the interlocking member 36 from the inside in the width direction of the paper feed tray 11 to restrict movement of the interlocking member 36. The second engagement member 32 is configured to elastically deform as the interlocking member 36 moves inward in the width direction of the paper feed tray 11, and to push the interlocking member 36 back outward in the width direction of the paper feed tray 11 by its elastic restoring force. Specifically, the second engagement member 32 has a rod shape that is approximately L-shaped in a plan view. The second engagement member 32 is positioned so that when the outer side surface of the interlocking member 36 is positioned so that it abuts against the inner side surface (rear side surface) of the interlocking member 36, the second engagement member 32 is fixed to the paper feed tray 11. At this time, the protrusion 112a of the second engagement member 112 fits into the recess 364 of the interlocking member 36, and the second short side member 363 can abut against the left side surface of the first engagement member 31. The second engaging member 32 is formed in a rod shape, with a free end at the tip and a fixed end at the base, and is therefore elastically deformable within a range in which the free end can move relative to the fixed end.

[0031] The third engagement member 33 engages with the tip of the first short side member 362 of the interlocking member 36 from the outside in the width direction of the paper feed tray 11, thereby moving the interlocking member 36. The third engagement member 33 is configured to elastically deform when the first short side member 362 moves in a direction (leftward) approaching the rack 22, i.e., when the interlocking member 36 moves leftward, and to move the interlocking member 36 toward the inside (rearward) in the width direction of the paper feed tray 11 by its elastic restoring force. Specifically, the third engagement member 33 has a rod shape that is approximately L-shaped in a plan view. The third engagement member 33 has an inclined surface 33a at its tip, and is positioned so that the inclined surface 33a engages with the tip of the first short side member 362 of the interlocking member 36, and its base end is fixed to the paper feed tray 11. The third engagement member 33 is formed in a rod shape, with its tip end being a free end and its base end being a fixed end, and is therefore elastically deformable within a range within which the free end can move relative to the fixed end.

[0032] The fourth engagement member 34 engages with the surface (left side surface) of the second short side member 363 opposite to the surface that contacts the first engagement member 31, and adjusts the left-right movement of the interlocking member 36. The fourth engagement member 34 is configured to elastically deform when the second short side member 363 moves in a direction away from the rack 22 (leftward), and to move the second short side member 363 in a direction toward the rack (rightward) by its elastic restoring force. Specifically, the fourth engagement member 34 has a rod shape that is approximately L-shaped in a plan view. The fourth engagement member 34 is positioned so that its tip abuts against the left side surface of the second short side member 363, and its base end is fixed to the paper feed tray 11. The fourth engagement member 34 is formed in a rod shape with its tip being a free end and its base end being a fixed end, and is therefore elastically deformable within a range within which the free end can move relative to the fixed end.

[0033] The fifth engagement member 35 engages with the teeth of the rack 22 and biases the rack 22 and, by extension, the width restricting member 21 inward. The fifth engagement member 35 is provided on the first short side member 362 and is configured to elastically deform when the interlocking member 36 moves inward in the width direction of the paper feed tray 11, causing the width restricting member 21 attached to the rack 22 to move inward in the width direction by its elastic restoring force to a position where it contacts both ends of the width direction of the sheet S. Specifically, the fifth engagement member 35 has a rod shape. The fifth engagement member 35 extends from the first short side member 362 toward the rack 22, with its tip positioned to engage with the teeth of the rack 22 and its base end fixed to the first short side member 362. The fifth engagement member 35 is formed in a rod shape with its tip being a free end and its base end being a fixed end, and is therefore elastically deformable within a range within which the free end can move relative to the fixed end.

[0034] The first to fourth engagement members 31 to 34, the first locking member 111 and the second locking member 112 are integrally formed with the paper feed tray 11. The fifth engagement member 35 is integrally formed with the interlocking member 36.

[0035] 3, a surface cover 14 is attached to the paper feed tray 11, covering the rack 22, the pinion 23, and the rack regulating member 30. The surface cover 14 has grooves 141 at both left and right ends, and the pair of width regulating members 21 can move in the width direction of the paper feed tray 11 through the grooves 141.

[0036] The paper feed tray 11 is also provided with scales 15 that serve as a guide for adjusting the pair of width restriction members 21 to the sheet size. For example, when the inner surfaces 21 a of the pair of width restriction members 21 are positioned at the scale 15, the scales 15 indicate that the inner surfaces 21 a of the pair of width restriction members 21 are spaced apart by the width of the sheet S corresponding to the scale 15. In this embodiment, the scales 15 are provided so that the pair of width restriction members 21 will have the width of the sheet S by aligning the inner side (rear side) of the base portion 211 of the front width restriction member 21 with the scale 15. The scales 15, like the protrusions 24 provided on the rack 22, are provided at positions corresponding to the main sizes of sheets S used in the image forming apparatus 1, such as LGL, A4, A5, and A6. In the embodiment shown in FIG. 3, the outermost scale 15 in the width direction of the paper feed tray 11 is for the LGL size, followed by the A4, A5, and A6 sizes, respectively, as you move inward. In this way, the protrusions 24 and the scales 15 are provided for the same sheet size. The scales 15 may be simply marked on the paper feed tray 11 by printing or the like, or may be formed in a convex shape that contacts the lower surfaces of the pair of width restriction members 21.

[0037] Next, the operation of the rack regulating member 30 of the sheet feeding device 10 will be described with reference to FIGS. 6 to 10. FIGS. 6 to 10 are plan views of the sheet feeding device 10 of this embodiment. FIG. 6 shows a state in which the first engagement member 31 to the fifth engagement member 35 and the interlocking member 36 are in their predetermined positions in the LGL size. FIG. 7 shows a state in which the protrusion 24 presses the first engagement member 31. FIG. 8 shows a state in which the third engagement member 33 has moved the rack 22. FIG. 9 shows a state in which the first engagement member 31 has climbed over the protrusion 24. FIG. 10 shows a state in which the first engagement member 31 to the fifth engagement member 35 and the interlocking member 36 are in their predetermined positions in the A4 size. FIGS. 6 to 10 are enlarged views of portion A in FIG. 4. Here, the operation of the rack regulating member 30 will be described using as an example a case in which the size of the sheet S to be fed is changed from the LGL size to the A4 size.

[0038] To change from LGL size to A4 size, the user moves the pair of width restriction members 21 inward in the width direction of the paper feed tray 11. Specifically, the user moves the width restriction member 21 located at the front toward the rear to a position that matches the width of the A4 size. At this time, the pair of racks 22 move inward. Because the force that moves the racks 22 when the user moves the width restriction members 21 exceeds a predetermined force, as the racks 22 move, the protrusions 24 push the first engagement members 31 in a direction away from the racks 22 (to the left), as shown in FIG. 7 .

[0039] The first engaging member 31 elastically deforms, and the tip of the first engaging member 31 moves in a direction away from the rack 22, so that the interlocking member 36 is pushed by the first engaging member 31 and moves in a direction away from the rack 22. As the interlocking member 36 moves, the first short side member 362 pushes the inclined surface 33a of the third engaging member 33, and the tip of the third engaging member 33 moves outward (toward the front). In addition, the second short side member 363 pushes the fourth engaging member 34, and the tip of the fourth engaging member 34 moves in a direction away from the rack 22. At this time, the fifth engaging member 35 engages with the teeth of the rack 22.

[0040] When the user moves the width restricting member 21 to a position corresponding to the width of A4 size, the user releases the width restricting member 21. As a result, the third engagement member 33 returns to its predetermined position due to its elastic restoring force, as shown in FIG. 8 . As the third engagement member 33 moves, the interlocking member 36 is pushed by the third engagement member 33 and moves inward (rearward). At this time, the fifth engagement member 35, which is engaged with the teeth of the rack 22, moves inward with its base end connected to the first short side member 362, while its tip remains positioned outward. Furthermore, as the interlocking member 36 moves, the tip of the second engagement member 32 moves inward (rearward) due to the push of the interlocking member 36. In this state, the elastic restoring force of the fifth engagement member 35 generates a biasing force that moves the rack 22 inward. Therefore, if there is a gap between the pair of width restricting members 21 and the sheet S, the fifth engagement member 35 moves the rack 22 inward.

[0041] As shown in FIG. 9, when the pair of width restricting members 21 matches the width of an A4-sized sheet S, the first engagement member 31 climbs over the protrusion 24 corresponding to the A4 size and returns to a predetermined position due to its elastic restoring force. This creates a gap between the first engagement member 31 and the second short side member 363, and the elastic restoring force of the fourth engagement member 34 moves the interlocking member 36 in a direction approaching the rack 22 (to the right) until the second short side member 363 comes into contact with the first engagement member 31. This disengages the third engagement member 33 from the first short side member 362. Then, as shown in FIG. 10, the elastic restoring force of the second engagement member 32 returns the interlocking member 36 to a predetermined position.

[0042] As described above, in the paper feeder 10 of the present invention, the rack 22 has the protrusion 24, and the first engagement member 31, which elastically deforms when a force greater than a predetermined value is applied, engages with the protrusion 24 from the widthwise outer side of the protrusion 24. This brings the protrusion 24 into contact with the first engagement member 31, physically restricting the movement of the protrusion 24, and therefore the rack 22 and the width restricting member 21. This provides a greater force restricting the movement of the rack 22 than the friction between the rack 22 and the wall surface surrounding the rack. Meanwhile, the first engagement member 31 is elastically deformable by the force applied by the user to move the width restricting member 21, making it possible to change the width of the width restricting member 21. As a result, the rack 22 can be restricted from moving outward in the width direction of the paper feed tray 11 when a force equal to or less than a predetermined value is applied, such as a reaction force of the sheet S being fed or vibrations occurring when the image forming apparatus 1 or the paper feeder 10 is operating. This allows the sheet S to be fed at a predetermined position without becoming skewed.

[0043] Furthermore, in the paper feeder 10 of the present invention, the rack regulating member 30 includes an interlocking member 36 and a fourth engaging member 34, which regulate the first engaging member 31 from deforming in a direction away from the rack 22. This increases the force with which the first engaging member 31 regulates the movement of the protrusion 24, and more reliably feeds the sheet S at a predetermined position without it becoming skewed.

[0044] The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above embodiments and can be embodied in various forms without departing from the spirit of the present invention. Furthermore, various inventions can be formed by appropriately combining multiple components disclosed in the above embodiments. For example, some components may be omitted from all components shown in the embodiments. The drawings may be shown mainly in a schematic manner to facilitate understanding. The number of components shown may differ from the actual number for convenience of drawing. Furthermore, the components shown in the above embodiments are merely examples and are not particularly limited, and various modifications are possible within a range that does not substantially deviate from the effects of the present invention.

[0045] For example, in the above embodiment, the fifth engagement member 35 engages with the teeth of the rack 22 so that the width regulating member 21 contacts both widthwise ends of the sheet S, but the present invention is not limited to this. For example, a configuration such as that shown in Fig. 11 is possible. Fig. 11 is a plan view showing another embodiment of the sheet feeding device 10 of the present invention.

[0046] As shown in FIG. 11 , the rack 22 having the protrusions 24 has an engagement portion 25 on a surface 22a on which the teeth of the rack 22 are formed, at a position corresponding to the protrusions 24, regardless of the teeth of the rack 22. In this embodiment, the surface 22a of the rack 22 facing the pinion 23 has teeth of the rack 22 formed on the lower part for engaging with the pinion 23, and the engagement portion 25 formed on the upper part. The engagement portion 25 is provided in a position corresponding to the protrusions 24 on the rack 22, corresponding to the sizes of the main sheets S used in the image forming apparatus 1, such as LGL, A4, A5, and A6. Specifically, the engagement portion 25 is provided at a position where the pair of width restricting members 21 contact both ends of the sheet S in the width direction, and where the engagement portion 25 can engage with the fifth engagement member 35. In this embodiment, the fifth engagement member 35 engages with the engagement portion 25 rather than the teeth of the rack 22. This allows the pair of width regulating members 21 to be positioned so as to contact both widthwise ends of the sheet S of each size even if the phase of the teeth of the rack 22 does not match the position corresponding to each size of the sheet S. [Industrial Applicability]

[0047] The present invention can be used in the fields of paper feeders and image forming devices. [Explanation of symbols]

[0048] 1. Image forming device 10 Paper feeder 11 Paper tray 20 Position holding part 21 Width control member 22 racks 23 Pinion 24 protrusions 25 Engagement part 30 Rack control member 31 first engaging member 32 second engagement member 33 third engaging member 34 fourth engaging member 35 fifth engaging member 36 Interlocking members 361 Long side members 362 First short side member 363 Second short side member S seat

Claims

1. a paper feed tray on which sheets are placed; a position holding unit that holds the position of the sheet placed on the paper feed tray; Equipped with The position maintaining unit is a pair of width restriction members attached to the paper feed tray so as to be movable in the width direction of the paper feed tray; a pair of racks connected to the pair of width regulating members, respectively; a pinion engaged with the pair of racks; a rack restricting member that restricts movement of the rack at a predetermined position; and One of the pair of racks has a protrusion on a surface opposite to a surface on which the teeth of the rack are formed, the rack regulating member is provided on the paper feed tray and has a first engaging member that engages with the protrusion from an outer side in the width direction of the paper feed tray; a plurality of the protrusions are provided for each sheet size along the longitudinal direction of the rack so that the pair of width regulating members engage with the first engaging member at a position corresponding to the width of a sheet of a predetermined size; The first engaging member is configured to be elastically deformable in a direction perpendicular to the width direction of the paper feed tray when a force equal to or greater than a predetermined value is applied to the first engaging member.

2. The rack regulating member is an interlocking member provided on the sheet feed tray so as to be movable in the longitudinal direction and the lateral direction of the rack; second engaging members, third engaging members, and fourth engaging members provided on the paper feed tray; a fifth engagement member provided on the interlocking member; and the interlocking member has a long-side member and a first short-side member and a second short-side member provided at both longitudinal ends of the long-side member, The longitudinal direction of the long side member is aligned with the short side direction of the rack, the first short side member and the second short side member are positioned with the rack in between, and the second short side member is disposed so as to abut against a surface of the first engaging member opposite to the rack, the second engagement member is configured to be elastically deformed when the interlocking member moves inward in the width direction of the paper feed tray, and to push the interlocking member back outward in the width direction of the paper feed tray by an elastic restoring force; the third engagement member is configured to engage with a tip end of the first short-side member, to be elastically deformed when the first short-side member moves in a direction approaching the rack, and to move the interlocking member inward in the width direction of the paper feed tray by an elastic restoring force; the fourth engagement member engages with a surface of the second short-side member opposite to a surface that contacts the first engagement member, and is elastically deformed when the second short-side member moves in a direction away from the rack, and is configured to move the second short-side member in a direction approaching the rack by an elastic restoring force, The paper feeding device described in claim 1, wherein the fifth engagement member is provided on the first short side member, engages with the teeth of the rack, and is configured to elastically deform when the interlocking member moves toward the inside of the paper feed tray in the width direction, and to move the width regulating member attached to the rack to a position contacting both ends of the sheet in the width direction by elastic restoring force.

3. the rack having the protrusion has an engaging portion on a surface on which teeth of the rack are formed, the engaging portion being located at a position corresponding to the protrusion and not associated with the teeth of the rack; The paper feeding device according to claim 2 , wherein the fifth engagement member engages with the engagement portion.

4. An image forming apparatus comprising the paper feeder according to any one of claims 1 to 3.

Images