JP2017105611A - Sheet feeding device and image formation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feeding device which can reduce the friction between a sheet delivered by a delivery member and a regulation member without retreating the regulation member upward.SOLUTION: A regulation member 5 regulates the position of sheets loaded in a cassette 102 and biased in the prescribed direction. A feeding roller 118 presses and delivers the sheets loaded in the cassette 102. A separation part 8 conveys the sheets delivered by the feeding roller 118. A lock mechanism 85 separates the sheets loaded in the cassette 102 from the position regulated by the regulation member 5 regardless of pressing by the feeding roller 118 when conveying the sheets delivered from the feeding roller 118 by the conveyance roller 6.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an image forming apparatus, an image reading apparatus, a sheet feeding apparatus equipped in a sheet processing apparatus, and the like, and an image forming apparatus equipped with the sheet feeding apparatus.

  2. Description of the Related Art Sheet feeding devices that take out the topmost sheets one by one from the stacked sheets and feed them to an image forming unit, an image reading unit, a sheet processing unit, etc. are widely used. In such a sheet feeding apparatus, the uppermost sheet positioned at a certain height position is fed from the stacked sheet bundle to the separation unit by a half-moon-like half-moon roller.

  In Patent Document 1, the uppermost sheet is detected by a sensor and the lift mechanism of the sheet stacking member is operated to position the sheet stacked on the sheet stacking member at a predetermined sheet feeding position. On the other hand, a configuration is known in which a sheet stacked on a sheet stacking member spring-biased upward is positioned at a predetermined sheet feeding position by bringing a regulating member into contact with the uppermost sheet. In the feeding device having such a regulating member, the sheet stacking member is biased after the half-moon roller or the like as the feeding member is separated from the surface of the sheet, so that the sheet and the regulating member abut again.

JP 2006008343 A

  As shown in Patent Document 1, in the configuration in which the uppermost sheet stacked on the sheet stacking member is positioned at a predetermined sheet feeding position, a sensor for detecting the upper surface position of the sheet or a lift mechanism of the sheet stacking member is used. A certain motor or the like is required, resulting in high cost. Further, as described above, in the configuration in which the regulating member and the stacked sheets are in contact with each other, the sheet is pressed by the regulating member, so that the frictional force between the drawn sheet and the next sheet increases and double feed occurs. There is a fear.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet feeding apparatus that prevents double feeding of sheets fed by a feeding member with a simple configuration.

  The sheet feeding apparatus according to the present invention includes a stacking unit on which sheets are stacked, a regulation unit that regulates a position of a sheet stacked on the stacking unit and biased in a predetermined direction, and a sheet stacked on the stacking unit. A feeding unit that presses and sends the sheet, a conveyance unit that conveys a sheet that is sent out by the sending unit, and a sheet that is sent from the sending unit is stacked on the stacking unit when the conveyance unit conveys the sheet. A separation unit that separates the sheet from a position regulated by the regulation unit regardless of pressing of the delivery unit.

  In the sheet feeding apparatus of the present invention, it is possible to prevent double feeding of sheets fed by the feeding member with a simple configuration.

1 is an explanatory diagram of a configuration of an image forming apparatus. It is a perspective view of a paper feed unit. FIG. 6 is an explanatory diagram of a configuration of a main part of a paper feeding unit. It is explanatory drawing of the locked state of a locking mechanism. It is explanatory drawing of the lock release state of a locking mechanism. FIG. 10 is an explanatory diagram of a sheet feeding operation in the sheet feeding apparatus. FIG. 10 is a perspective view of a paper feeding unit according to a second embodiment. 10 is an explanatory diagram of a sheet feeding operation in Embodiment 2. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Embodiment 1>
(Image forming device)
FIG. 1 is an explanatory diagram of the configuration of the image forming apparatus. As shown in FIG. 1, the image forming apparatus 100 is a copier that arranges an image reading apparatus 100A on an apparatus main body 100B and forms a monochrome image by an electrophotographic method. The image reading apparatus 100 </ b> A generates an image data by reading an image of the lower surface of the original placed between the original pressing plate 104 and the original table glass 106 by the reading head 108.

  The image forming unit 150 forms an image on the sheet P. The apparatus main body 100B surrounds the photosensitive drum 112 and includes a charging roller 114, an exposure device 110, a developing device 120, a transfer roller 124, and a drum cleaning device 140. The charging roller 114 is applied with an oscillating voltage obtained by superimposing an AC voltage on a DC voltage, and charges the photosensitive drum 112 to a uniform potential.

  The exposure device 110 scans the surface of the photosensitive drum 112 with a laser beam to form an electrostatic latent image on the surface of the photosensitive drum 112. The developing device 120 carries the developer on the developing roller 116 and develops the electrostatic latent image on the photosensitive drum 112 into a toner image. The transfer roller 124 is applied with a DC voltage, and transfers the toner image carried on the photosensitive drum 112 onto a sheet passing through the transfer portion T. The drum cleaning device 140 collects transfer residual toner on the surface of the photosensitive drum 112 by sliding the photosensitive drum 112 with a cleaning blade.

  The sheet on which the toner image has been transferred by the transfer unit T is conveyed to the fixing device 128, and is heated and pressed at the nip N between the fixing roller 128a and the pressure roller 128b, and the image is fixed on the sheet. The sheet on which the image is fixed is discharged to a discharge tray 132 by a discharge roller 130.

  A sheet feeding unit 101, which is an example of a sheet feeding apparatus, feeds a sheet P from the cassette 102 to the image forming unit 150. The sheet P is fed from the cassette 102 arranged at the lower part of the apparatus main body 100B to the transfer unit T. The cassette 102 is detachably attached to the apparatus main body 100B and is loaded with sheets. The feed roller 118 feeds the sheet P from the cassette 102 to the separation unit 8 by rotating in contact with the uppermost sheet among the sheets stacked on the cassette 102. The separation unit 8 pushes the double-feed sheet back to the cassette 102 and transfers the uppermost sheet to the registration roller 9. The registration roller 9 receives the leading edge of the sheet P in a stopped state, corrects the skew of the sheet P, and rotates according to the timing of the toner image on the photosensitive drum 112 to send the sheet P to the transfer unit T.

(Paper Feeder)
FIG. 2 is a perspective view of the paper feeding unit. FIG. 3 is an explanatory diagram of the configuration of the main part of the paper feeding unit. As shown in FIG. 2, the sheet feeding unit 101 separates the sheets P drawn from the cassette 102 by the feeding roller 118 one by one in the separating unit 8.

  In the cassette 102 that is an example of a stacking unit, sheets are stacked on a stacking plate 2 that is an example of a stacking member. The sheet P on the stacking plate 2 is aligned at the trailing edge by the trailing edge regulating plate 4 and is aligned at the side edge by the pair of side edge regulating plates 103. Here, the upstream side in the conveyance direction of the sheet P is defined as the trailing edge, the downstream side in the conveyance direction of the sheet P is defined as the leading edge, and the end in the width direction orthogonal to the conveyance direction of the sheet is defined as the side edge. ing. The rear end regulating plate 4 is detachably attached to the stacking plate 2, and the attachment position can be changed according to the size of the sheet P accommodated in the cassette 102.

  The cassette 102 is provided with regulating members 5 at both ends in the width direction on the downstream side of the feeding roller 118. A regulating member 5, which is an example of a regulating unit, regulates the position of a sheet that is stacked on the cassette 102 and is urged in a predetermined direction (upward). The regulating member 5 is in contact with both corners of the leading end of the uppermost sheet P stacked on the stacking plate 2 and regulates the height position of the upper surface of the sheet P stacked on the stacking plate 2.

  A feeding roller 118 is provided at a position above the leading end of the uppermost surface of the sheets P stacked on the stacking plate 2. A feeding roller 118, which is an example of a feeding unit, pushes the sheets stacked on the cassette 102 downward and sends the uppermost sheet stacked on the stacking plate 2.

  A separation unit 8 is provided downstream of the feeding roller 118. The separation unit 8 separates the multi-feed sheet at the nip between the conveyance roller 6 and the separation roller 7. The separation unit 8, which is an example of a conveyance unit, conveys the sheet sent by the feeding roller 118 by the conveyance roller 6. The separating unit 8 separates the sheets fed by the feeding roller 118 one by one by the separating roller 7 and feeds only the uppermost sheet to the image forming unit 150.

  As shown in FIG. 3, the sheets P are stacked on the stacking plate 2 of the cassette 102. The stacking plate 2 can rotate up and down on the downstream side with the upstream side in the conveyance direction of the sheet P as a rotation axis. The loading plate 2 is biased upward by a biasing force of a pressing spring 3 provided between the bottom surface of the cassette 102 and the loading plate 2. The pressing spring 3, which is an example of an urging member, urges the stacking plate 2 so that the sheets stacked on the stacking plate 2 are brought into contact with the regulating member 5.

  The feeding roller 118 receives a driving force in the transport direction from the driving source 80 via the speed reduction mechanism 81. The driving force is transmitted to the feeding roller 118 through the rotating shaft 8a. The feeding roller 118 rotates in the direction of arrow A, contacts the upper surface of the uppermost sheet P among the sheets P stacked on the stacking plate 2, pulls out the sheet P from the cassette 102, and goes to the separation unit 8. Send it out.

  The feeding roller 118 includes a first region having a first distance from the rotation center to the circumferential surface, and a second region having a second distance having a distance from the rotation center to the circumferential surface smaller than the first distance. Has a half moon roller. After feeding the uppermost sheet by rubbing an area with a large radius, the feeding roller 118 faces the uppermost sheet with an area with a smaller radius so as not to prevent conveyance.

  In the separation unit 8, which is an example of a conveyance unit, the separation roller 7 is brought into contact with the conveyance roller 6. The transport roller 6 is driven in the transport direction together with the feed roller 118 from the drive source 80 through the speed reduction mechanism 81. The separating unit 8 sandwiches the sheet sent by the feeding roller 118 and separates the multi-feed sheet. The conveyance roller 6 drives the sheet in the conveyance direction. The separation roller 7 nips a sheet with the conveyance roller 6 and drives in a direction opposite to the conveyance direction.

  The separation roller 7 is driven in a direction opposite to the conveyance direction via a one-way clutch 82 from a drive source 80 through a speed reduction mechanism 81. The separation roller 7 is driven and rotated by the conveyance roller 6 while applying a load to the sheet P conveyed by the conveyance roller 6. The separation roller 7 generates a certain resistance to the conveyance of the sheet P by the conveyance roller 6, but since the friction coefficient between the sheets P is small, only the uppermost sheet P in contact with the conveyance roller 6 is a double-feed sheet. The sheet is conveyed to the downstream side while sliding. Thereby, the plurality of sheets P stacked on the stacking plate 2 are separated one by one.

(Lock mechanism)
FIG. 4 is an explanatory diagram of the lock state of the lock mechanism. FIG. 5 is an explanatory diagram of the unlocking state of the locking mechanism. 4 and 5, (a) is a view seen from the outside in the rotation axis direction, and (b) is a view seen from the inside in the rotation axis direction.

  As shown in FIG. 3, the lock mechanism 85, which is an example of a separation unit, feeds the sheet P stacked on the cassette 102 when the transport roller 6 transports the sheet P sent from the feed roller 118. It is separated from the position regulated by the regulating member 5 regardless of the pressure of 118. The lock mechanism 85 holds the sheet stacked on the stacking plate 2 at a position separated from the regulating member 5 when the feeding roller 118 is separated from the sheet stacked on the stacking plate 2.

  The pressing spring 3, which is an example of an urging member, urges the stacking plate 2 so that the sheets stacked on the stacking plate 2 are brought into contact with the regulating member 5. The lock mechanism 85 holds the stacking plate 2 in a separated state against the urging force of the pressing spring 3. The lock mechanism 85 holds the state where the feeding roller 118 is separated from the regulating member 5 by locking the stacking plate 2 pushed down in the process of feeding the sheets stacked on the stacking plate 2 with the one-way clutch 86. . The lock mechanism 85 holds the position of the stacking plate 2 pushed down by the feeding roller 118 in the process in which the feeding roller 118 sends out the sheets stacked on the stacking plate 2.

  Pinion gears 11 are attached to both ends in the width direction of the stacking plate 2, and rack gears 12 are disposed at positions facing the pinion gears 11. A pinion gear 11, which is an example of a rotating body, is provided on the stacking plate 2. A rack gear 12, which is an example of a guide member, meshes with the pinion gear 11 and guides the pinion gear 11 so as to be movable in a direction of pushing down the stacking plate 2.

  A one-way clutch 86 is provided inside the pinion gear 11. The one-way clutch 86 enables rotation of the pinion gear 11 in one direction and locks rotation in the other direction so that the stacking plate 2 can be pushed down with respect to the rack gear 12. By the one-way clutch 86, the pinion gear 11 rotates only in the direction of arrow B, that is, the downward direction of the stacking plate 2. As the loading plate 2 descends, the pinion gear 11 descends along the rack gear 12 while idling. That is, the one-way clutch 86, which is an example of the one-way rotating means, allows the stacking plate 2 to be pushed down with respect to the rack gear 12 by allowing the pinion gear 11 to rotate in one direction with respect to the stacking plate 2.

  For this reason, the stacking plate 2 can be pushed down against the urging force of the pressing spring 3, but the rise from the pushed-down position is locked. As a result, the stacking plate 2 keeps the state where the entire sheet stacked on the stacking plate 2 is pressed against the feeding roller 118 and holds the uppermost sheet P away from the regulating member 5. To do.

(unlock)
As shown in FIG. 4A, in the state where the uppermost sheet P is separated from the regulating member 5, the next uppermost sheet P can be sent out even if a region where the radius of the feeding roller 118 is large is used. Can not. Therefore, as shown in FIG. 4B, before the sheet P is fed by the region where the radius of the feeding roller 118 is large, the engagement of the pinion gear 11 and the rack gear 12 is released. Before the feeding roller 118 sends out the sheets stacked on the stacking plate 2, the separation of the stacking plate 2 is released so that the feeding roller 118 can send out the sheets. Before the feeding roller 118 sends out the sheets stacked on the stacking plate 2, the meshing between the pinion gear 11 and the rack gear 12 is released.

  As shown in FIG. 5A, the release mechanism 88 releases the meshing between the pinion gear 11 and the rack gear 12 before the feeding roller 118 sends out the sheets stacked on the stacking plate 2. Release the 2 position. As a result, the stacking plate 2 biased by the pressing spring 3 rises, and the uppermost sheet P stacked on the stacking plate 2 comes into contact with the regulating member 5.

  As shown in FIG. 3, the rack gear 12 is attached to the release member 13 so as to be movable in the horizontal direction, and is biased toward the pinion gear 11 by the pressing spring 14. The release mechanism 88 releases the locked state of the pinion gear 11 and the rack gear 12 by the lock mechanism 85. As shown in FIG. 4A, the release member 13, which is an example of a moving member, supports the rack gear 12 so as to be movable away from the pinion gear 11. As shown in FIG. 4B, the release member 13 is also movable in the height direction. As shown in FIG. 5B, the lock release unit 10, which is an example of an interlocking member, moves the release member 13 in the height direction in conjunction with the operation of the feeding roller 118. The engagement protrusions 12b and the holes 13b, which are examples of the release mechanism, move the rack gear 12 away from the pinion gear 11 as shown in FIG. 5A in conjunction with the movement of the release member 13 in the height direction.

  As shown in FIG. 3, the lock release portions 10 are disposed at both ends of the rotation shaft 8 a of the feeding roller 118. The lock release unit 10 moves the release member 13 in the height direction in conjunction with the operation of the feeding roller 118. As the feed roller 118 rotates, the lock release unit 10 pushes down the release member 13 disposed below the lock release unit 10. When the lock release unit 10 pushes down the release member 13, the rack gear 12 is separated from the pinion gear 11 and released from engagement.

  As shown in FIG. 5B, the release member 13 supports the rack gear 12 so as to be movable away from the pinion gear 11, and is movable in the height direction. The engagement protrusion 12 b and the hole 13 b separate the rack gear 12 from the pinion gear 11 in conjunction with the movement of the rack gear 12 in the height direction.

  When the lock release unit 10 pushes down the release member 13, the engagement protrusion 12 b is guided along the shape of the hole 13 b provided in the release member 13, and the rack gear 12 having the engagement protrusion 12 b is separated from the pinion gear 11. Move in the direction you want. As a result, the meshing between the rack gear 12 and the pinion gear 11 is released.

(Sheet feeding operation)
FIG. 6 is an explanatory diagram of a sheet feeding operation in the sheet feeding apparatus. In FIG. 6, (a) is the initial position, (b) is the disengagement operation, (c) is the sheet height position restriction, (d) is the feeding roller conveyance operation, and (e) is the separation conveyance roller conveyance operation. is there.

  As shown in FIG. 6A, the loading plate 2 is forced upward by the urging force of the pressing spring 3, but the pinion gear 11 is not rotated by the one-way clutch 86 arranged in the pinion gear 11, and the loading plate 2 is loaded. The plate 2 is restricted from rising. In this state, the feeding roller 118 and the separating unit 8 start to rotate, and the paper feeding operation is started.

  As shown in FIG. 6B, the lock release unit 10 provided on the shaft of the feed roller 118 pushes down the release member 13. Thereby, the release member 13 is pushed down, and the pinion gear 11 and the rack gear 12 are separated. Then, the stacking plate 2 is raised by the urging force of the pressing spring (3: FIG. 3), and the sheet P comes into contact with the regulating member 5.

  As shown in FIG. 6C, when the feeding roller 118 further rotates, the lock release unit 10 is separated from the release member 13, and the rack gear 12 is engaged with the pinion gear 11 by the pressing of the pressing spring 14. After that, the pressing unit 118a before the sheet conveying unit 118b of the feeding roller 118 shown in FIG. 6A presses the sheet P and pushes down the stacking plate 2 to a predetermined height position. The sheet P is fed to the separation unit 8 by the sheet conveying unit 118b of the feeding roller 118 as shown in FIG.

  As shown in FIG. 6E, the rack gear 12 and the pinion gear 11 are engaged when the sheet conveying portion 118b of the feeding roller 118 is removed from the sheet P. Therefore, the pinion gear 11 is a one-way clutch. 86 does not rotate, and the loading plate 2 is restricted from rising.

  As a result, the separation unit 8 can convey the sheet P in a state where the sheet P does not contact the regulating member 5 and the feeding roller 118.

(Effect of Embodiment 1)
In the first embodiment, the upper surface of the sheet P stacked on the stacking plate 2 can be locked at a position where it does not contact the regulating member 5. Accordingly, the sheet P can be transported in a state where there is no frictional load on the regulating member 5, and the transport member positioned on the downstream side can perform stable transport. Failure to send P is less likely to occur. When the conveying member is not a pair of rollers rotating in the conveying direction but the conveying member is a separation unit that separates the multi-feed sheets, the separation unit 8 and the sheet P on the stacking plate 2 are separated while separating the multi-feed sheets. The regulation member 5 does not contact. For this reason, the restricting member 5 does not become a load and the multi-feed sheet cannot be separated.

  In the first embodiment, the lock mechanism 85 holds the position of the stacking plate 2 against the urging force of the pressing spring 3. For this reason, it is possible to move the sheet P to a position where it comes into contact with the regulating member 5 without requiring motor driving or the like only by releasing the lock mechanism 85.

  In the first embodiment, the lock mechanism 85 holds the position of the stacking plate 2 that is pressed down in the process in which the feeding roller 118 sends out the sheets stacked on the stacking plate 2. For this reason, the sheet P can be separated from the regulating member 5 without requiring motor driving or the like.

  In the first embodiment, the lock mechanism 85 releases the holding of the stacking plate 2 before the feeding roller 118 comes into contact with the sheets stacked on the stacking plate 2. For this reason, the sheet P can be sent from the cassette 102 without waste using the entire contact length of the feeding roller 118.

  In the first embodiment, the pinion gear 11 is provided on the stacking plate 2 and moves up and down. For this reason, it is possible to accommodate a large amount of sheets P in the cassette 102 by securing a larger lifting stroke of the stacking plate 2 than when the rack gear 12 is provided on the stacking plate 2 to be moved up and down.

<Embodiment 2>
In the first embodiment, the embodiment in which the delivery member is a half-moon roller has been described. In contrast, in the second embodiment, the feeding member is a lifting roller that moves up and down relative to the sheet. In the second embodiment, since the configuration and operation other than the delivery member are the same as those in the first embodiment, the same reference numerals as those in FIGS. 2 and 6 are used in FIGS. A duplicate description is omitted.

  FIG. 7 is a perspective view of the sheet feeding unit according to the second embodiment. FIG. 8 is an explanatory diagram of the sheet feeding operation in the second embodiment. 8, (a) is the initial position, (b) is the disengagement operation, (c) is the sheet height position restriction, (d) is the feeding roller conveyance operation, and (e) is the separation conveyance roller conveyance operation. is there.

  As shown in FIG. 7, the feeding roller 119 is held by the feeding roller holder 15 and rotates around the shaft 15a. The feeding roller holder 15 is provided with a spring (not shown), and a force is always applied in the direction of pressing against the sheet P.

  The feeding roller holder 15 is connected to a driving source (not shown), and the feeding roller 119 descends to the upper surface of the sheet according to the rotation of the driving source and rotates to feed paper.

  As shown in FIG. 8, (a) to (b) are states in which the feeding roller 119 is raised, but in (c) to (d), the feeding roller 119 descends to the sheet P to feed paper. Meanwhile, the lock release unit 10 drives the release member 13 and attaches and detaches the pinion gear 11 and the rack gear 12 as in the first embodiment.

  Thereafter, when the sheet P reaches the separation unit 8, the feeding roller 119 moves up as shown in (e). Thereby, the separation unit 8 can convey the sheet P in a state where the sheet P does not contact the upper surface regulating member 5 and the feeding roller 119.

  Also in the second embodiment, the upper surface regulation of the sheets P stacked on the stacking plate can be locked at a position where the sheet P does not contact the feeding roller 119 and the regulating member 5. As a result, the separation unit 8 can convey the sheet in a state where there is no load on the feeding roller and the upper surface regulating member, and stable feeding can be performed.

<Other embodiments>
The sheet feeding apparatus according to the present invention is not limited to the specific components, part forms, and part names in the first embodiment. Another embodiment in which a part or all of the configuration of the first embodiment is replaced with an equivalent member is also possible.

  In the first embodiment, the example of the paper feeding unit 101 mounted on the image forming apparatus 100 has been described. However, the sheet feeding apparatus according to the first embodiment can be mounted not only in a copying machine but also in a printer, a facsimile machine, or the like. The image reading apparatus can be implemented as a sheet feeding apparatus that supplies a document from which an image is read to the image reading unit. The sheet processing apparatus can also be implemented as a sheet feeding apparatus that supplies unused recording materials to the sheet processing unit.

  In the first embodiment, a one-way clutch is used as a mechanism for rotating the pinion gear 11 only in one direction. This may be replaced with a ratchet gear.

  In Embodiment 1, the feeding roller 118 is a half-moon roller. This may be replaced by a moving roller provided so as to be able to move up and down and come in contact with and separate from the sheets stacked on the stacking plate 2. It may be replaced with a friction member that moves in the transport direction on the stacked sheets and pulls out the sheets.

2 loading plate, 3 pressing spring, 4 rear end regulating plate 5 regulating member, 6 conveying roller, 7 separating roller 8 separating unit, 9 registration roller, 10 lock releasing unit 11 pinion gear, 12 rack gear, 12b engaging projection 13 releasing member , 13b hole, 14 pressure spring 80 drive source, 81 deceleration mechanism, 82, 86 one-way clutch 85 locking mechanism, 88 release mechanism 100 image forming apparatus, 100A image reading apparatus, 100B apparatus main body 101 paper feed section, 102 cassette, 103 side Edge regulating plate 110 Exposure device, 112 Photosensitive drum, 114 Charging roller 116 Developing roller, 118 Feeding roller, 118a Pressing unit 118b Sheet conveying unit, 119 Feeding roller 124 Transfer roller, 128 Fixing device 120 Developing device, 130 Discharging roller 132 Discharge tray 140 Drum cleaning device, 1 50 Image forming part P sheet

Claims (12)

A stacking unit on which sheets are stacked;
A regulation unit that regulates the position of the sheet loaded on the stacking unit and biased in a predetermined direction;
A sending unit that presses and sends the sheets stacked on the stacking unit;
A transport unit for transporting a sheet sent by the sending unit;
A separation unit that separates a sheet stacked on the stacking unit from a position regulated by the regulation unit without being pressed by the delivery unit when the conveyance unit conveys the sheet fed from the sending unit; A sheet feeding apparatus comprising: The stacking unit includes a stacking member on which sheets are stacked, and a biasing member that biases the stacking member so that the sheets stacked on the stacking member abut against the regulation unit,
The sheet feeding device according to claim 1, wherein the separation unit separates the stacking member against an urging force of the urging member.   3. The sheet feeding according to claim 2, wherein the separation unit separates the stacking member pushed down in a process in which the feeding unit sends out the sheets stacked on the stacking member from the regulation unit. apparatus.   The sheet feeding apparatus according to claim 3, wherein the separation unit releases the separation of the stacking member before the feeding unit sends out the sheets stacked on the stacking member.   The spacing portion includes a rotating body provided on the stacking member, a guide member that meshes with the rotating body and guides the rotating body in a direction to push down the stacking member, and the guide member The sheet feeding apparatus according to claim 4, further comprising: a one-way rotating unit that allows the rotating member to rotate in one direction with respect to the stacking member so that the stacking member can be pushed down.   The sheet feeding device according to claim 5, wherein the separation unit releases the meshing between the rotating body and the guide member before the feeding unit sends out the sheets stacked on the stacking unit. . The spacing portion is
A movable member that supports the guide member movably in a direction away from the rotating body and is movable in a height direction;
A release mechanism that moves the guide member away from the rotating body in conjunction with the movement of the moving member in the height direction;
The sheet feeding apparatus according to claim 6, further comprising an interlocking member that moves the moving member in the height direction in conjunction with an operation of the feeding unit.   The sheet feeding apparatus according to claim 5, further comprising a pinion gear as the rotating body and a rack gear as the guide member.   The conveyance unit includes a conveyance roller that drives a sheet in a conveyance direction, and a separation roller that nips the sheet between the conveyance roller and drives the sheet in a direction opposite to the conveyance direction. The sheet feeding apparatus according to any one of 1 to 8.   The delivery unit includes a first region having a first distance from the rotation center to the circumferential surface, and a second region having a second distance having a distance from the rotation center to the circumferential surface smaller than the first distance. The sheet feeding device according to any one of claims 1 to 9, wherein the sheet feeding device is a half-moon roller.   10. The sheet feeding apparatus according to claim 1, wherein the feeding unit is a moving roller provided so as to be able to contact with and separate from the sheets stacked on the stacking unit. The sheet feeding device according to any one of claims 1 to 11,
An image forming apparatus comprising: an image forming unit configured to form an image on a sheet fed by the sheet feeding device.

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