JP2012101881A - Sheet feeding apparatus and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feeding apparatus that can maintain a side end regulation member to a regulation position for regulating a side end of a sheet without deteriorating useability, and to provide an image forming apparatus.SOLUTION: A pressing cam 106 is provided in a sheet stacking part 102 so as to be slidable in a width direction. The pressing cam 106 presses the side end presses the side end regulation parts 101a, 101b as the sheet stacking part 102 rises in a sheet direction and returns the side end regulation parts 101a, 101b when the side end parts 101a, 101b for regulating the side end parts in the sheet width direction are deviated from the side end position in the sheet width direction.

Description

  The present invention relates to a sheet feeding device and an image forming apparatus, and in particular, is provided in a sheet storage portion so as to be movable in a width direction, and for regulating a shift of a side end regulating member that regulates a side end position in the width direction of a sheet. Concerning configuration.

  2. Description of the Related Art Today, image forming apparatuses such as printers and copiers are widely used in which an image is formed by feeding a sheet to an image forming unit. Such an image forming apparatus includes a sheet feeding device that feeds sheets stacked in a sheet storage unit such as a paper feed cassette or a manual feed tray to the image forming unit using a sheet feeding member. Is common.

  Here, the paper feed cassette and the manual feed tray are provided with side end regulating members that regulate the position in the width direction perpendicular to the sheet feeding direction of the stacked sheets so that sheets of various sizes can be stored. (See Patent Document 1). In such a sheet feeding cassette or a manual feed tray, by regulating the side edge of the sheet by the side edge regulating member, it is possible to stably feed the sheet regardless of the sheet size.

  Further, conventionally, in order to prevent the side edge position of the sheet from being shifted due to backlash of the side edge regulating member, there is a type in which the side edge regulating member has a convex shape and the main body of the paper feed cassette or the manual feed tray is provided with a concave portion. (See Patent Document 2). Then, when the side end regulating member moves to a predetermined regulating position according to the sheet size, the regulation for regulating the deviation of the side end regulating member by causing the convex portion of the side end regulating member to enter the concave portion of the main body. I am trying to improve my power.

JP 2001-31256 A JP-A-6-234432

  However, in the conventional sheet feeding apparatus and image forming apparatus, in such a configuration in which the convex portion of the side end regulating member enters the concave portion of the main body, a large force is applied when the side end regulating member is moved in the width direction. It had to deteriorate usability. Note that if the amount of entry is reduced in order to improve usability, the regulating force for regulating the displacement of the side end regulating member is weakened. When the regulation force is weakened in this way, the side edge regulating member is gradually opened in the width direction due to the play of the side edge regulating member or the vibration during feeding, and the side edge position of the sheet is shifted, thereby deteriorating the printing accuracy. Invite.

  Therefore, the present invention has been made in view of such a current situation, and a sheet feeding device capable of keeping a side end regulating member at a regulating position that regulates a side edge of a sheet without deteriorating usability, and An object of the present invention is to provide an image forming apparatus.

  The present invention includes a sheet storage unit having a sheet stacking unit that can move up and down by stacking sheets, a feeding roller that is provided above the sheet storage unit and that feeds the sheets stacked on the sheet stacking unit, In the sheet feeding apparatus, when feeding a sheet, the sheet stacking unit is raised in conjunction with rotation of the feeding roller so as to press the sheet against the feeding roller. And a side end regulating portion that regulates a side end position in the width direction of the sheet, and a regulation that the side end regulating portion regulates the side end of the sheet. And a pressing portion that presses the side end regulating portion in the width direction to return to the regulating position when the sheet stacking portion is raised when the sheet stacking portion is at a position shifted from the position. .

  As in the present invention, when the side end restricting portion deviates from the restricting position, the side end restricting portion is returned to the restricting position until the sheet feeding is started as the sheet stacking portion rises, thereby improving usability. The side end regulating member can be kept in the regulated position without deteriorating the angle.

1 is a diagram illustrating a configuration of a color laser printer that is an example of an image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a first diagram illustrating a configuration of a manual sheet feeder provided in the laser printer. FIG. 5 is a second diagram illustrating the configuration of the manual sheet feeding unit. The figure explaining the fixing method of the press cam provided in the said manual paper feed part. The figure explaining the operation | movement at the time of sheet | seat feeding of the said press cam. FIG. 6 is a first diagram illustrating a configuration of a manual sheet feeder provided in an image forming apparatus according to a second embodiment of the present invention. FIG. 5 is a second diagram illustrating the configuration of the manual sheet feeding unit. The figure explaining the operation | movement at the time of sheet | seat feeding of the said press cam. FIG. 10 is a diagram illustrating a configuration of a manual sheet feeder provided in an image forming apparatus according to a third embodiment of the present invention. The figure explaining the operation | movement at the time of sheet | seat feeding of the said press cam.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail based on the drawings. FIG. 1 is an overall configuration diagram of a color laser printer which is an example of an image forming apparatus according to a first embodiment of the present invention. In FIG. 1, 1 is a color laser printer, and 1A is a full-color laser printer main body (hereinafter referred to as a printer main body). The printer main body 1A includes an image forming unit 1B that forms an image on a sheet, and a paper feed that feeds the sheet. A portion 103A and the like are provided.

  The image forming unit 1B includes a photosensitive drum 1 (1a to 1d) which is an image carrier, and forms toner images of four colors of yellow, magenta, cyan and black, which are detachably attached to the printer main body 1A. A process cartridge 3 (3a to 3d) is provided. In addition, the image forming unit 1B includes a scanner unit 9 that is disposed vertically below the process cartridge 3 and that irradiates a laser beam based on image information to form an electrostatic latent image on the photosensitive drum 1.

  Here, each process cartridge 3 includes a developing unit 4 (4a to 4d) and a cleaner unit 5 (5a to 5d). The developing unit 4 that visualizes a toner image by attaching toner to the electrostatic latent image has a developing roller 6 (6a to 6d), a developer application roller 7 (7a to 7d), and a toner container. ing. The cleaner unit 5 includes a photosensitive drum 1, a charging roller 2 (2a to 2d) that uniformly charges the surface of the photosensitive drum, a drum cleaning blade 8 (8a to 8d), and a waste toner container. .

  In FIG. 1, reference numeral 10 denotes an intermediate transfer belt unit. The intermediate transfer belt unit 10 includes an intermediate transfer belt 51 and a primary transfer roller 50 (50a to 50d) disposed inside the intermediate transfer belt 51. It has. The intermediate transfer belt 51 is stretched around a driving roller 52 and a tension roller 53, and the tension roller 53 applies tension in the direction of the arrow.

  Further, the primary transfer roller 50 is disposed so as to face each of the photosensitive drums 1 and is configured to apply a transfer bias by a bias applying unit (not shown). Then, by applying a primary transfer bias to the intermediate transfer belt 51 by the primary transfer roller 50, each color toner image on the photosensitive drum is sequentially transferred to the intermediate transfer belt 51. A full color image is formed.

  A secondary transfer unit 13 includes a driving roller 52 and a secondary transfer roller 60, and sequentially transfers a full color image formed on the intermediate transfer belt 51 to a sheet. A fixing unit 15 applies heat and pressure to the image formed on the sheet to fix the toner image. The fixing unit 15 is rotatable with respect to the pressure roller 15a and the pressure roller 15a and is in contact with a predetermined pressure. A heating sleeve 15b is provided.

  A sheet discharge unit 80 discharges the sheet on which the image is fixed in the fixing unit 15 to the sheet stacking unit 18 provided on the upper surface of the printer main body. The sheet discharge unit 80 includes a discharge roller pair 17, a switchback roller pair 19, a re-conveying path 37, and the like that are sheet discharge means.

  The sheet feeding unit 103 </ b> A includes a cassette sheet feeding unit 20 and a manual sheet feeding unit 100. The cassette paper feeding unit 20 includes a paper feeding cassette 21 that is detachably attached to the printer main body 1A, a pickup roller 24 that feeds the sheet S stored in the paper feeding cassette 21, a feed roller 22, a separation roller 23, and the like. have. Reference numeral 21a denotes a side end regulating member that is provided in the sheet feeding cassette 21 so as to be movable in a width direction orthogonal to the sheet feeding direction and regulates the side end position of the sheet S in the width direction.

  The manual sheet feeding unit 100 includes a sheet stacking unit 102 that stacks sheets, a feeding roller 103 that feeds the uppermost sheet of the sheet stacking unit 102, and a separation pad 104. When the sheets stacked on the sheet stacking unit are fed, the sheet stacking unit 102 is lifted, the sheets stacked on the sheet stacking unit are brought into pressure contact with the feeding roller 103, and then the feeding roller 103. Is rotated to feed out the sheet S.

  Next, an image forming operation of the color laser printer 1 configured as described above will be described. When an image signal is input to the scanner unit 9 from a personal computer (not shown) or the like, a laser beam corresponding to the image signal is emitted from the scanner unit 9 onto the photosensitive drum. At this time, the surface of the photosensitive drum 1 is uniformly charged to a predetermined polarity and potential in advance by the charging roller 2, and an electrostatic latent image is formed on the surface by irradiating laser light from the scanner unit 9. The Thereafter, the electrostatic latent image is developed by the developing unit 4 and visualized.

  For example, the scanner unit 9 first irradiates the photosensitive drum 1a with laser light based on the image signal of the yellow component color of the document, thereby forming a yellow electrostatic latent image on the photosensitive drum 1a. The yellow electrostatic latent image is developed with yellow toner from the developing unit 4a to be visualized as a yellow toner image. Thereafter, when the toner image arrives at the primary transfer portion where the photosensitive drum 1a and the intermediate transfer belt 51 come into contact with the rotation of the photosensitive drum 1a, the primary transfer bias applied to the primary transfer roller 50a causes The yellow toner image on the photosensitive drum is transferred onto the intermediate transfer belt.

  Next, when the portion carrying the yellow toner image of the intermediate transfer belt 51 moves, the magenta toner image formed on the photosensitive drum 1b by the same method as described above is transferred from the yellow toner image to the intermediate transfer belt. Transferred to the belt 51. Similarly, as the intermediate transfer belt 51 moves, the cyan toner image and the black toner image are transferred onto the yellow toner image and the magenta toner image, respectively, in the primary transfer portion. As a result, a full-color toner image is formed on the intermediate transfer belt. The toner remaining on the surface of the photosensitive drum after the toner image transfer is removed by the cleaner unit 5.

  In parallel with the toner image forming operation, for example, the sheet S accommodated in the paper feed cassette 21 is fed out by the pickup roller 24 and then one sheet at a time by the separation unit constituted by the feed roller 22 and the separation roller 23. Separated and transported. Thereafter, the sheet is conveyed to the registration roller pair 38 through the main body sheet feeding conveyance path 36. When the sheet is fed from the manual sheet feeding unit 100, the sheets S stacked on the sheet stacking unit are fed by the feeding roller 103 and then separated one by one by the separation pad 104. Thereafter, the sheet is conveyed to the re-conveying roller pair 35, passes through the main body sheet feeding / conveying path 36 and is conveyed to the registration roller pair 38.

  Next, after the leading edge of the sheet conveyed to the registration roller pair 38 is detected by a top sensor (not shown), the secondary transfer unit 13 aligns the position of the full color toner image on the intermediate transfer belt with the sheet S. Then, it is conveyed to the secondary transfer unit 13 by the registration roller pair 38. Then, in the secondary transfer unit 13, a four-color toner image on the intermediate transfer belt 51 is secondarily transferred onto the conveyed sheet S by applying a positive bias to the secondary transfer roller 60. After the secondary transfer onto the sheet S, the toner remaining on the intermediate transfer belt is removed by the transfer belt cleaning device 11, and the removed toner is collected in a waste toner collecting container (not shown).

  The sheet S after the transfer of the toner image is conveyed to the fixing unit 15 and heated and pressed by the pressure roller 15a and the heating sleeve 15b, and the full-color toner image is fixed on the surface thereof as a permanent image. Next, after the full-color toner image is fixed as a permanent image in this way, the sheet S is discharged and stacked from the sheet discharge port 81 to the sheet stacking unit 18 by the discharge roller pair 17 provided in the sheet discharge unit 80.

  By the way, the present color laser printer 1 can form images on both sides of a sheet. When images are formed on both sides of the sheet, the transfer path is switched by the switching member 16 before the sheet S reaches the discharge roller pair 17. As a result, the sheet S reaches the switchback roller pair 19 that can be rotated forward and backward while being guided by the switched switching member 16.

  Thereafter, the sheet S is switched back by the switchback roller pair 19 and is reversed by the double-sided conveyance roller pair 39 and the re-conveyance roller pair 35 provided in the re-conveyance path 37, and then is fed to the main body sheet feeding conveyance path 36. They are merged and conveyed to the registration roller pair 38 again. Thereafter, the sheet is conveyed to the secondary transfer unit 13 by the registration roller pair 38 and image formation is performed on the second surface. Then, the sheet S on which the image is formed on the second surface in this way passes through the fixing unit 15 and is fixed, and then is discharged and stacked from the sheet discharge port 81 to the sheet stacking unit 18 by the discharge roller pair 17. Is done.

  Meanwhile, the manual sheet feeder 100 is manually held by the manual sheet feeder main body 100A constituting the sheet storage section shown in FIG. 2 and the manual sheet feeder main body 100A so as to be pivotable in the vertical direction. The sheet stacking unit 102 is provided. In the sheet stacking section 102, a pair of left and right side end regulating members 101a and 101b for regulating the position of the end in the width direction of the stacked sheets shown in FIG. 3 are movable (slidable) in the width direction. ). The sheets stacked on the sheet stacking unit 102 are fed in the direction of arrow D in FIGS.

  Here, the pair of left and right side end regulating members 101a and 101b extend in the width direction as shown in FIG. 3B, and mesh with a pinion gear 105 provided at the center in the width direction of the sheet stacking portion 102. Racks 101a1 and 101b1 are provided. The side end regulating members 101a and 101b are movable in conjunction with the width direction by a rack and pinion mechanism including the racks 101a1 and 101b1 and the pinion gear 105. Since the side end regulating members 101a and 101b are merely connected by the racks 101a1 and 101b1, the opening / closing operation can be smoothly performed without load.

  Further, in one embodiment of the side end regulating members 101a and 101b, on the outer surface of the side end regulating member 101b, a pressed member 108 as shown in FIGS. 3A and 3C has a width. It is provided to be movable in the direction. In the present embodiment, a pressing force absorbing spring 117, which is an elastic member, is provided between the pressed member 108 and the side end regulating member 101b. The pressed member 108 is normally in a state where the pressed member 108 protrudes laterally from the side end regulating member 101b. In the present embodiment, the pressed member 108 is formed with a tapered slope 119 shown in FIG. 5, which will be described later, that is, a slope 119 having a tapered surface.

  On the other hand, the feed roller 103 of the manual sheet feeder 100 is engaged with the feed shaft 109 as shown in FIG. 2 and rotates in the direction of arrow A together with the feed shaft 109. A feeding roller 110 is rotatably attached to the feeding shaft 109. A friction pad 103a for separating the sheet S is provided at a position facing the feeding roller 103 of the manual sheet feeder main body 100A. The friction pad 103a is provided on the upper surface of the friction pad holder 103b urged in the direction of the feed roller 103 by a separation spring (not shown), and the friction pad holder 103b feeds in the stage before feeding. The roller 110 is in pressure contact.

  A pair of lifting cams 111 a and 111 b for lifting and lowering the sheet stacking portion 102 are engaged with both ends of the feeding shaft 109. Here, the sheet stacking unit 102 is provided on the manual sheet feeding unit main body 100 </ b> A so as to be pivotable (movable up and down) via a shaft 112, and the direction of the lifting cams 111 a and 111 b by a pair of stacking springs 113. Is being energized.

  The sheet stacking portion 102 is provided with two sliding portions 114 that slide with the lifting cams 111a and 111b. The sliding portions 114 are urged by the stacking spring 113 to move the lifting cam 111a. , 111b. With this configuration, when the feed roller 103 (feed shaft 109) rotates, the sheet stacking unit 102 moves up and down by the lift cams 111a and 111b in conjunction with the rotation.

  By the way, in this Embodiment, the press cam 106 which presses the to-be-pressed member 108 of one side end regulating member 101b is inserted in the feeding shaft 109. Here, a tapered slope 118, that is, a slope 118 having a tapered surface is formed at the tip of the pressing cam 106 as shown in FIG. As shown in FIG. 4A, the pressing cam 106 is formed by elastically locking the pressing cam fixing claw 120 in a square hole 115 formed in the feeding shaft 109. It is fixed in the state of being inserted into.

  A plurality of the square holes 115 are formed on the feeding shaft 109 according to the size of the sheet to be fed, and the position of the pressing cam 106 is changed according to the size of the sheet. Thus, the position can be changed according to the size of the sheet. Then, when the position of the pressing cam 106 is changed, as shown in FIG. 4B, the pressing cam 106 is moved to the arrow E after the locking with the square hole 115 of the pressing cam fixing claw 120 is elastically released. After that, it is locked in the square hole 115 at a position corresponding to the sheet size. Note that FIG. 2 described above shows an example in which the side end regulating members 101a and 101b and the pressing cam 106 that can change the position in the axial direction are aligned with the position of the A5 size.

  Next, the sheet feeding operation of the manual sheet feeder 100 having the above configuration will be described. When feeding a sheet installed on the uppermost part of the sheets S stacked on the sheet stacking unit 102, the feeding shaft 109 is indicated by the arrow A in FIG. Rotate in the direction. Due to the rotation of the feed shaft 109, not only the feed roller 103 but simultaneously the lifting cams 111a and 111b and the pressing cam 106 are rotated in the same direction.

  As the elevating cams 111a and 111b rotate, the sheet stacking portion 102 in which the sliding portion 114 is in pressure contact with the elevating cams 111a and 111b rises in the direction indicated by the arrow B, as shown in FIG. Move to position. Thereafter, the sheet S is fed in the direction of arrow D by the feed roller 103 rotating in the direction indicated by arrow A.

  By the way, at the stage before starting the feeding operation, that is, before the feeding shaft 109 rotates, the phase of the pressing cam 106 fixed to the feeding shaft 109 as shown in FIG. A slope 118 provided on 106 is in a phase located above. That is, in the stage before starting the feeding operation, the slope 118 of the pressing cam 106 and the slope 119 of the pressed member 108 do not face each other.

  Next, when the feeding operation is started and the pressing cam 106 rotates integrally with the feeding shaft 109, the sheet is pressed by the feeding roller 103 as shown in FIG. The inclined surface 118 of the cam 106 is positioned to face the inclined surface 119 of the pressed member 108. Here, the side end regulating members 101a and 101b may be opened in the width direction by play or feeding operation. In this case, when the sheet stacking unit 102 is subsequently raised, before the sheet is fed, the two inclined surfaces 118 and 119 come into contact with each other as shown in FIG. Due to this shape, the pressing cam 106 presses the pressed member 108.

  As a result, the pressed member 108 moves in the direction of arrow C shown in FIG. 5C, and accordingly, the side end regulating member 101b also moves in the direction of arrow C via the pressing force absorbing spring 117. When the side end regulating member 101b moves in this way, as described above, the other side end regulating member 101a interlocked by the rack and pinion mechanism also moves in the direction of the arrow C as shown in FIG. Moving.

  In this way, the side end regulating members 101a and 101b are moved in the width direction until the sheet feeding is started by pressing the pressed member 108 by the pressing cam 106 as the sheet stacking unit 102 is raised. be able to. As a result, the side end regulating members 101a and 101b that have moved to a position farther from the sheet than the position that regulates the side end position of the sheet due to backlash or feeding operation are set to a predetermined side that matches the sheet size immediately before feeding. It can be returned to the end regulation position.

  As a result, the side edge of the sheet S stacked on the sheet stacking unit 102 is regulated to an appropriate position by the side edge regulating members 101a and 101b. Therefore, the sheet S is fed without causing misalignment or skewing. The Further, since the inclined surface 118 of the pressing cam 106 and the inclined surface 119 of the pressed member 108 are provided, it is possible to correct even if the positions of the side end regulating members 101a and 101b are slightly shifted in the width direction.

  As described above, in this embodiment, each time a sheet is fed, the side end regulating members 101a and 101b are pressed against the side of the sheet stacked on the sheet stacking unit 102. Thus, when the side end regulating members 101a and 101b are deviated from the regulated position, the side end regulating members 101a and 101b are returned to the regulated position before the sheet feeding is started as the sheet stacking unit 102 is raised. Can do. As a result, when the side end regulating members 101a and 101b are operated, a large force is not required. Therefore, the side end regulating members 101a and 101b can be kept at the regulated position without deteriorating usability, and usability and printing accuracy are achieved. It is possible to achieve both.

  Next, a second embodiment of the present invention will be described. 6 and 7 are diagrams illustrating the configuration of the manual sheet feeder 100 provided in the image forming apparatus according to the present embodiment. 6 and 7, the same reference numerals as those in FIGS. 2 and 3 described above indicate the same or corresponding parts.

  In the present embodiment, as shown in FIG. 6, a plurality of pressing cams 206 a to 206 d and 207 a to 207 d are inserted through the feeding shaft 109. Here, tapered slopes 218a to 218d are formed at the tips of the pressing cams 207a to 207d as shown in FIG. In addition, the same taper-shaped slope is formed also in the front-end | tip of the press cams 206a-206d.

  In the present embodiment, four pressing cams 206a to 206d and 207a to 207d for small sizes such as A4 / LTR, B5 / EXE, A5, and postcards are installed on the left and right sides of the feeding roller 103. Yes. The pressing cams 206a to 206d and 207a to 207d are attached to the feeding shaft 109 with the same configuration as that of the first embodiment described above.

  Further, in the present embodiment, as shown in FIG. 7, the pressed members 208a and 208b pressed by the pressing cams 206a to 206d and 207a to 207d on both of the side end regulating members 101a and 101b are movable in the width direction. Is provided. In the present embodiment, a pressing force absorbing spring 117 is provided between the pressed members 208a and 208b and the side end regulating members 101a and 101b. The pressed members 208a and 208b are normally protruded laterally from the side end regulating members 101a and 101b by the pressing force absorbing spring 117. In this embodiment, the pressed member 208b is formed with a tapered slope 219b shown in FIG. The pressed member 208a is also formed with a similar tapered slope.

  If the positions of the pressing cams 206a to 206d and 207a to 207d are A4 / LTR sizes, the A4 size is the narrower sheet when the pressed members 208a and 208b of the side end regulating members 101a and 101b are most pressed. It is installed to fit the end of the. Further, as described above, the pressing force absorbing spring 117 is provided between the pressed members 208a and 208b and the side end regulating members 101a and 101b.

  Accordingly, the displacement of the side end regulating members 101a and 101b can be corrected, and the pressing force absorbing spring 117 can prevent the sheet from being bent due to excessive pressing. Further, the positions of the pressing cams 206a to 206d and 207a to 207d are also set to positions corresponding to B5 which is a narrow sheet similarly for B5 and EXE, and each of A5 and small size sheets is A5. And it is installed at a position that matches the postcard.

  Further, when a sheet having a non-standard size is passed, the pressing cams 206a to 206d and 207a to 207d are moved as described in the first embodiment, and the feeding shaft 109 is formed. This can be handled by fixing with the square hole 115. In the present embodiment, the side end regulating members 101a and 101b are aligned with the A5 size position.

  Next, a sheet feeding operation of the manual sheet feeder 100 having the above configuration will be described. When feeding a sheet installed on the uppermost part of the sheets S stacked on the sheet stacking unit 102, the feeding shaft 109 is driven in a direction indicated by an arrow A in FIG. Rotate. As the feed shaft 109 rotates, not only the feed roller 103 but also the lifting cams 111a and 111b and the press cams 206a to 206d and 207a to 207d rotate in the same direction.

  As the elevating cams 111a and 111b rotate, the sheet stacking portion 102 in which the sliding portion 114 is in pressure contact with the elevating cams 111a and 111b rises in the direction indicated by the arrow B, as shown in FIG. Move to position. Thereafter, the sheet S is fed in the arrow D direction by the feeding roller 103 that rotates in the direction indicated by the arrow A.

  By the way, at the stage before starting the feeding operation, as shown in FIG. 8A, the phases of the pressing cams 207a to 207d fixed to the feeding shaft 109 are the phases in which the inclined surfaces 218a to 218d are positioned upward. It has become. That is, in the stage before starting the feeding operation, the inclined surfaces 218a to 218d of the pressing cams 207a to 207d and the inclined surface 219b of the pressed member 208b do not face each other. Although not shown in the figure, the phases of the pressing cams 206a to 206d fixed to the feeding shaft 109 are also phases in which the inclined surfaces are located above. That is, in the stage before starting the feeding operation, the inclined surfaces of the pressing cams 206a to 206d do not face the inclined surface of the pressed member 208a.

  Next, when the feeding operation is started and the feeding shaft 109 rotates, the pressing cams 206 a to 206 d and 207 a to 207 d rotate together with the feeding shaft 109. Thus, before the sheet is fed by the feeding roller 103, the inclined surface 218c of the pressing cam 207c is in a position facing the inclined surface 219b of the pressed member 208b, as shown in FIG. 8B. Here, the side end regulating members 101a and 101b may be opened in the width direction by play or feeding operation. In this case, when the sheet stacking unit 102 is raised thereafter, the two inclined surfaces 218c and 219b come into contact with each other and the two inclined surfaces 218c and 219b are brought into contact with each other as shown in FIG. Due to this shape, the pressing cam 207c presses the pressed member 208b.

  As a result, the pressed member 208b moves in the direction of arrow C shown in FIG. 8C, and accordingly, the side end regulating member 101b also moves in the direction of arrow C via the pressing force absorbing spring 117. Here, the other side end regulating member 101a also moves in the direction of the arrow C as shown in FIG. As a result, the side end regulating members 101a and 101b that have moved to a position farther from the sheet than the position that regulates the side end position of the sheet due to backlash or feeding operation are set to a predetermined side that matches the sheet size immediately before feeding. It can be returned to the end regulation position.

  As described above, in the present embodiment, the feeding shaft 109 is provided with a plurality of pressing cams 206a to 206d and 207a to 207d. As a result, the same effects as those of the first embodiment described above can be obtained, and the effort for changing the position of the pressing cam can be reduced.

  By the way, in the first and second embodiments described so far, the cam for pressing the side end regulating members 101a and 101b is attached to the feeding shaft 109, but the present invention is not limited to this. . If the pressed member can be pressed when the sheet stacking unit 102 is raised, for example, the pressing member is provided in the printer main body 1A, and is provided in the open / close door that is opened when a jam occurs in the manual sheet feeding unit. Anyway.

  Next, a third embodiment of the present invention in which the pressing member is provided on the opening / closing door will be described. FIG. 9 is a diagram for explaining the configuration of the manual sheet feeder provided in the image forming apparatus according to the present embodiment. In FIG. 9, the same reference numerals as those in FIG. 2 described above indicate the same or corresponding parts.

  In FIG. 9, reference numeral 70 denotes an opening / closing door, and reference numeral 306 denotes a rib which is a pressing member for pressing a side end regulating member formed integrally with the opening / closing door 70. In the present embodiment, four ribs 306 for small sizes such as A4 / LTR, B5 / EXE, A5, and postcards are installed on the left and right sides of the open / close door 70.

  Here, if the positions of the ribs 306a to 306d and 307a to 307d are A4 / LTR size positions, the pressed members 308a and 308b of the side end regulating members 101a and 101b are the narrowest sheets. It is installed to fit the end of A4 size. Accordingly, it is possible to achieve both the correction of the displacement of the side end regulating members 101a and 101b and the prevention of bending of the sheet due to excessive pressing.

  Similarly, B5 and EXE are installed at positions corresponding to B5, which is a narrow sheet, and A5 and small-sized sheets are respectively matched to A5 and postcards. In the present embodiment, the side end regulating members 101a and 101b are installed at positions corresponding to the A5 size.

  Next, a sheet feeding operation of the manual sheet feeder 100 having the above configuration will be described. When feeding a sheet installed at the top of the sheet S stacked on the sheet stacking unit 102, the feeding shaft 109 is driven in a direction indicated by an arrow A in FIG. Rotate. As the feed shaft 109 rotates, not only the feed roller 103 but also the lifting cams 111a and 111b rotate in the same direction.

  As the elevating cams 111a and 111b rotate, the sheet stacking portion 102 rises in the direction indicated by the arrow B together with the sliding portions 114 that are in pressure contact with the elevating cams 111a and 111b, as shown in FIG. Move to position. Here, as shown in FIG. 10A, tapered slopes 318 a to 318 d are formed at the lower ends of the ribs 307 a to 307 d provided on the opening / closing door 70. In addition, although not shown in figure, the taper-shaped slope is formed also in the lower end part of the other ribs 306a-306d.

  Further, the side end regulating members 101a and 101b installed in the sheet stacking portion 102 are provided with pressed members 308a and 308b each having a tapered slope 319b formed at the tip. The ribs 307a to 307d and the pressed members 308a and 308b are separated as shown in FIG. 10A before the sheet stacking unit 102 is raised, that is, before the feeding operation is started. In the position.

  On the other hand, when the sheet stacking unit 102 is lifted, the ribs 306a to 306d and 307a to 307d are lifted as shown in FIG. 10B immediately before the sheet is fed. The pressed members 308a and 308b are contacted and pressed. As a result, the side end regulating member 101b is moved in the direction of the arrow C by the pressing force absorbing spring 117 as shown in FIG. As a result, the side end regulating members 101a and 101b that have moved to a position farther from the sheet than the position that regulates the side end position of the sheet due to backlash or feeding operation are set to a predetermined side that matches the sheet size immediately before feeding. It can be returned to the end regulation position.

  Then, after the ribs 306a to 306d and 307a to 307d press the pressed members 308a and 308b in this way, the sheet S rotates in the direction indicated by the arrow A as shown in FIG. Is fed in the direction of arrow D. At this time, the sheet S having the appropriate side end position by the side end regulating members 101a and 101b returned to the predetermined side end regulating position is fed without causing misalignment or skew.

  As described above, as in the present embodiment, a plurality of pressing cams 206a to 206d and 207a to 207d are provided on the open / close door of the main body of the manual sheet feeder (the main body of the sheet feeding apparatus). As a result, the same effects as those of the first embodiment described above can be obtained, and the effort for changing the position of the pressing cam can be reduced.

  In each of the embodiments described so far, both the pressed member and the pressing cam (or rib) are formed with tapered slopes, but the present invention is not limited to this. A taper surface may be formed on a contact surface that contacts at least one of the pressing cam (or rib) and the pressed portion and the other of the pressing cam (or rib) and the pressed portion.

DESCRIPTION OF SYMBOLS 1 ... Color laser printer, 1A ... Full color laser printer main body, 1B ... Image formation part, 70 ... Opening / closing door, 100 ... Manual feed part, 101a, 101b ... Side edge regulating member, 102 ... Sheet stacking part, 103 ... Feeding Roller, 106 ... Pressing cam, 108 ... Pressed member, 109 ... Feeding shaft, 117 ... Pressure absorbing spring, 118 ... Slope of pressing cam, 119 ... Slope of pressed member, 206a to 206d, 207a to 207d ... Pressing Cam, 208a, 208b ... pressed member, 218a-218d ... slope of the pressing cam, 219b ... slope of the pressed member, 306 ... rib, 308a, 308b ... pressed member, 318a-318d ... rib slope, 319b ... covered Slope of pressing member, S ... sheet

Claims (7)

A sheet storage unit having a sheet stacking unit capable of moving up and down by stacking sheets, and a feeding roller provided above the sheet storage unit and configured to feed the sheets stacked on the sheet stacking unit, In the sheet feeding device that raises the sheet stacking portion in conjunction with the rotation of the feeding roller and presses the sheet against the feeding roller,
A side end regulating portion that is slidable in the width direction perpendicular to the sheet feeding direction and regulates the side end position in the width direction of the sheet;
When the side end regulating portion is at a position deviated from the regulation position for regulating the side edge of the sheet, the side edge regulating portion is pressed in the width direction and returned to the regulation position as the sheet stacking portion rises. And a sheet feeding device characterized by comprising:   The sheet feeding device according to claim 1, wherein the pressing portion returns the side end regulating portion to the regulation position before the feeding of the sheet by the feeding roller is started. The side end regulating portion is provided to be slidable in the width direction, and a pressed portion that is pressed by the pressing portion as the sheet stacking portion rises, and the pressed portion protrudes in a direction away from the regulating position. An elastic member to be
When the pressed part is pressed by the pressing part, the side end regulating part returns to the regulated position while sliding the pushed part against the elastic member toward the regulated position. The sheet feeding apparatus according to claim 1 or 2. The pressing portion is one or a plurality of cams provided on a shaft of the feeding roller and rotating integrally with the feeding roller,
4. The sheet feeding apparatus according to claim 3, wherein a taper surface is formed on an abutting surface of at least one of the cam and the pressed portion and the other of the cam and the pressed portion.   The sheet feeding device according to claim 4, wherein the position of the cam in the axial direction can be changed. The pressing part is one or a plurality of ribs provided above the sheet stacking part,
The sheet feeding device according to claim 3, wherein a taper surface is formed on a contact surface of at least one of the rib and the pressed portion that contacts the other of the rib and the pressed portion.   An image forming apparatus comprising: an image forming unit; and the sheet feeding device according to claim 1 for feeding a sheet to the image forming unit.

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