JP2023128988A - sheet feeding device - Google Patents

Abstract

To provide a sheet feeding device in which, even when a position relation that a pressure plate is positioned above and a lifting part below is inverted, the position relation can be easily restored to relation as before, and the pressure plate or the lifting part is prevented from being damaged.SOLUTION: In a sheet feeding device 1, a lifting part 60 includes: a first transmission part 61 capable of moving in a first direction R1 for raising a pressure plate 31 to a feeding position and a second direction R2 for lowering the pressure plate 31 to a non-feeding position; and a second transmission part 62 which has an arm 62A and is supported by the first transmission part 61 so as to be movable together with the movement of the first transmission part 61 in the first direction R1 and the movement thereof in the second direction R2. When the first transmission part 61 moves in the second direction R2 in a state where the arm 62A is positioned above the pressure plate 31, the arm 62A is pressed by the pressure plate 31 to move so as to retreat from the pressure plate 31 independently from the first transmission part 61, and when the arm 62A moves below the pressure plate 31, it moves together with the first transmission part 61.SELECTED DRAWING: Figure 6

Description

The present invention relates to a sheet feeding device.

An example of a conventional sheet feeding device is disclosed in Patent Document 1. This sheet feeding device includes a pickup roller, an MP tray, and a link member.

The pickup roller feeds the sheet. The MP tray supports sheets. The MP tray has a pressure plate that is movable up and down between a feeding position where the uppermost sheet is brought into contact with a pickup roller and a non-feeding position below the feeding position.

A supported portion is integrally formed on the pressure plate. The link member abuts the supported portion of the pressure plate from below and is movable to move the pressure plate up and down.

JP 2020-104973 Publication

By the way, in the above-mentioned conventional sheet feeding device, when the pressure plate moves up and down, for example, when removing a jammed sheet during feeding, or when the operation is suddenly stopped during feeding due to a power outage, etc., the pressure plate moves up and down. There is a risk that the positional relationship in which the link member is at the bottom may be reversed.

Then, when attempting to move the link member from above the pressure plate to below the pressure plate in order to restore the original positional relationship between the pressure plate and the link member, the link member and the supported portion of the pressure plate interfere with each other. If the pressure plate or the link member is damaged, the pressure plate or the link member may be damaged in some cases.

The present invention has been made in view of the above-mentioned conventional situation, and even if the positional relationship is reversed, with the pressure plate at the top and the elevating part at the bottom, it can be easily restored to its original state, thereby preventing damage to the pressure plate or the elevating part. It is an object of the present invention to provide a sheet feeding device that can suppress

The sheet feeding device of the present invention includes a feeding roller that feeds the sheet;
A feeding tray that supports sheets, and a pressure plate that can move up and down is provided at a feeding position where the uppermost sheet comes into contact with the feeding roller and at a non-feeding position below the feeding position. the feeding tray having;
an elevating part that has an arm that contacts the pressure plate from below and is movable to move the pressure plate up and down,
The lifting unit is movable in a first direction in which the pressure plate is raised from the non-feeding position to the feeding position and in a second direction in which the pressure plate is lowered from the feeding position to the non-feeding position. a first transmission section;
a second transmission section having the arm and supported by the first transmission section so as to be movable with the movement of the first transmission section in the first direction and the movement in the second direction;
When the first transmission section moves in the first direction with the arm located below the pressure plate, the arm of the second transmission section contacts the pressure plate from below and moves the first transmission section. pushing the pressure plate up to the feeding position,
When the first transmission section moves in the second direction while the arm is below the pressure plate, the arm of the second transmission section contacts the pressure plate from below and moves the first transmission section. lowering the pressure plate to the non-feeding position by moving with the
When the first transmitting section moves in the second direction with the arm above the pressure plate, the arm of the second transmitting section is pressed by the pressure plate and thereby moves with the first transmitting section. is configured to move independently to retreat from the pressure plate, and to move together with the first transmission unit when the arm moves below the pressure plate.

In the sheet feeding device of the present invention, when the pressure plate moves up and down, for example, when removing a jammed sheet during feeding, or when the operation is suddenly stopped during feeding due to a power outage, etc., the pressure plate moves up and down. There is a risk that the positional relationship in which the arm of the unit is at the bottom may be reversed.

In this respect, in this sheet feeding device, the elevating section includes a first transmission section and a second transmission section. In other words, the elevating section is divided into two parts.

When the positional relationship between the pressure plate and the arm of the lifting section is restored to its original position, that is, when the first transmission section moves in the second direction while the arm is above the pressure plate, the arm of the second transmission section By being pushed by the pressure plate, it moves independently of the first transmission part and retreats from the pressure plate. As a result, in the elevating section, the arm of the second transmission section can reach below the pressure plate without being obstructed by the pressure plate, and then the arm of the second transmission section moves together with the first transmission section to eliminate the abnormality. can.

Therefore, in the sheet feeding device of the present invention, even if the positional relationship is reversed, with the pressure plate at the top and the elevating section at the bottom, it can be easily restored to its original state, and damage to the pressure plate or the elevating section can be suppressed.

FIG. 2 is a partial cross-sectional view of the image forming apparatus according to the embodiment, mainly showing a state in which the feeding tray is in the unfolded position and the pressure plate is in the non-feeding position. FIG. 3 is a perspective view of the feeding tray, mainly showing a state in which the feeding tray is in the unfolded position and the pressure plate is in the non-feeding position. FIG. 3 is a partial top view of the feeding tray and the elevating section, mainly showing the feeding tray in the unfolded position. FIG. 2 is a partial cross-sectional view similar to FIG. 1, showing a state in which the feeding tray is in a storage position. FIG. 2 is a partial cross-sectional view similar to FIG. 1, mainly showing a state in which the feeding tray is in the unfolded position and the pressure plate is in the feeding position. FIG. 3 is a partial perspective view of the pressure plate and the elevating section, mainly showing the pressure plate in the feeding position. It is a perspective view of an elevating part. It is an exploded perspective view of an elevating part. It is a sectional view of an elevating part. FIG. 3 is a side view showing the pressure plate and the elevating section, mainly showing the pressure plate in a non-feeding position. FIG. 11 is a side view similar to FIG. 10, mainly showing a state in which the pressure plate is in the feeding position. 11 is a side view similar to FIG. 10, showing a state in which the positional relationship is reversed, with the pressure plate at the top and the arm of the elevating section at the bottom; FIG. FIG. 11 is a side view similar to FIG. 10, in which the positional relationship is reversed, with the pressure plate on top and the arm of the lifting unit at the bottom, and then the lifting unit descends, and the arm of the second transmission unit is pushed by the pressure plate, so that the first It is a figure which shows the state which started rocking|swiveling so that it might retreat from a pressure plate independently of a transmission part. FIG. 11 is a side view similar to FIG. 10, showing a state in which the elevating part has further descended from the state shown in FIG. 13, and the arm of the second transmission part has further swung so as to retreat from the pressure plate.

Embodiments embodying the present invention will be described below with reference to the drawings.

(Example)
As shown in FIG. 1, an image forming apparatus 1 of Example 1 is an example of a specific embodiment of a sheet feeding apparatus of the present invention. In FIG. 1, the front 9S side of the casing 9 is defined as the front of the device, the top surface side of the casing 9 is defined as the upper side of the device, and the front-rear direction and up-down direction are displayed. The front-rear direction and up-down direction shown in each figure after FIG. 2 are all shown corresponding to FIG. 1.

Further, the width direction DW1 of the feeding tray 3 shown in FIG. 2 and the like is a direction perpendicular to the front-rear direction and the up-down direction. Furthermore, one side of the width direction DW1 shown in FIG. 2 and the like is the front side of the page in FIG.

As shown in FIG. 1, the image forming apparatus 1 includes a housing 9, a paper feed cassette 2C, an image forming section 2, and a transport section (not shown). The housing 9 is approximately box-shaped and has a discharge tray 9T on its upper surface. The paper feed cassette 2C is located in the lower part of the housing 9 and accommodates a plurality of sheets in a stacked state.

The image forming section 2 is located in the upper part of the housing 9. The image forming section 2 forms an image on a sheet using an electrophotographic method, a thermal method, an inkjet method, or other general image forming method.

A transport unit (not shown) supplies sheets one by one from the paper feed cassette 2C to the image forming unit 2. The image forming section 2 forms an image on the sheet. Thereafter, a conveyance section (not shown) conveys the sheet on which the image is formed and discharges it onto the discharge tray 9T.

The image forming apparatus 1 also includes a feeding tray 3 . The feeding tray 3 is a multi-purpose tray for feeding a plurality of types of sheets SH having different sizes, thicknesses, etc. to the image forming section 2.

The feeding tray 3 is located on the front surface 9S side of the housing 9. The housing 9 supports the feeding tray 3 so as to be rotatable between the unfolded position shown in FIGS. 1 to 3 and the housed position shown in FIG.

As shown in FIG. 1, the expanded position of the feeding tray 3 is a position extending forward from the front surface 9S. As shown in FIG. 4, the storage position of the feeding tray 3 is a position where it stands up along the front surface 9S of the housing 9.

As shown in FIGS. 1 to 3, when the feed tray 3 is in the unfolded position, the upwardly facing surface of the feed tray 3 becomes the support surface 3A capable of supporting the sheet SH. The feeding direction DF1 of the sheet SH supported by the support surface 3A is perpendicular to the width direction DW1 of the feeding tray 3, and is a direction that slopes downwardly toward the rear.

Note that when describing the shapes of the plurality of members constituting the feeding tray 3, the attitude of the feeding tray 3 in the unfolded position is used as a reference in the vertical direction and the front-back direction.

As shown in FIG. 1, the housing 9 has a feeding tray accommodating section 90. As shown in FIG. The feeding tray accommodating portion 90 is recessed rearward from the upper portion of the front surface 9S. The inner wall of the feed tray accommodating portion 90 located on the other side in the width direction DW1, that is, on the back side of the paper in FIG. 1, has an arm guide 90G having a substantially elongated hole shape. Although not shown, the inner wall of the feed tray accommodating portion 90 located on one side in the width direction DW1, that is, on the front side in the paper of FIG. 1, also has an arm guide 90G.

As shown in FIGS. 2 and 3, the image forming apparatus 1 includes link arms 91A and 91B. One end 91A1 of the link arm 91A has a shaft portion that projects in one direction in the width direction DW1. One end 91B1 of the link arm 91B has a shaft portion that projects to the other side in the width direction DW1.

As shown in FIG. 1, one end 91B1 of the link arm 91B is connected to the housing 9 by inserting the shaft portion into the arm guide 90G of the feeding tray housing section 90. Although not shown, one end 91A1 of the link arm 91A is similarly connected to the housing 9.

<Feed roller, separation roller, separation pad>
The housing 9 includes a roller support member 29 located below the feed tray accommodating portion 90 and a feed guide member 28 located below the roller support member 29. The image forming apparatus 1 includes a feeding roller 21, a separation roller 22, and a separation pad 22A.

The roller support member 29 rotatably supports the feeding roller 21 and the separation roller 22. Further, the roller support member 29 supports the feed roller 21 and the separation roller 22 so that the positions of the rotation axes of the feed roller 21 and the separation roller 22 do not change. The lower portions of each of the feeding roller 21 and the separation roller 22 are exposed below the roller support member 29.

The feeding roller 21 is located above the supporting surface 3A and upstream in the feeding direction DF1 from the downstream end 3D of the supporting surface 3A in the feeding direction DF1. The separation roller 22 is located downstream of the downstream end 3D of the support surface 3A in the feeding direction DF1.

The feeding guide member 28 has a regulating surface 28A and a feeding surface 28B. The regulating surface 28A is a forward facing surface extending in the width direction DW1. The regulating surface 28A is inclined so that its upper end is located further back than its lower end. The regulating surface 28A faces the downstream end 3D of the supporting surface 3A from downstream in the feeding direction DF1. The feeding surface 28B is an upwardly facing surface connected to the upper end of the regulating surface 28A. The feeding surface 28B extends downstream in the feeding direction DF1.

The regulating surface 28A abuts the downstream end of the sheet SH supported by the supporting surface 3A in the feeding direction DF1. The feeding roller 21 feeds the uppermost sheet SH supported by the support surface 3A in the feeding direction DF1. The feeding surface 28B guides the sheet SH fed by the feeding roller 21.

The feeding guide member 28 supports the separation pad 22A at a position directly below the separation roller 22 so as to be exposed from the feeding surface 28B. The separation pad 22A is pressed toward the separation roller 22.

The feeding roller 21, separation roller 22, and separation pad 22A feed the sheets SH supported on the support surface 3A to the image forming section 2 one by one. The image forming section 2 forms an image on the sheet SH. Thereafter, a transport unit (not shown) transports the sheet SH on which the image is formed and discharges it onto the discharge tray 9T.

<Detailed configuration of feeding tray>
The feed tray 3 includes a feed tray main body 30 and a pressure plate 31 shown in FIGS. 1 to 4, and a subtray 30E shown in FIGS. 1 and 4.

As shown in FIG. 1, the housing 9 supports the feeding tray main body 30 so as to be swingable around an opening/closing axis X30. The opening/closing axis X30 is located on the lower end side of the feeding tray accommodating portion 90 and extends in the width direction DW1.

As shown in FIGS. 2 and 3, the feeding tray main body 30 includes a flat plate portion 35, link rails 36A and 36B, and a sub-tray housing portion 37.

The flat plate portion 35 extends from the opening/closing axis X30 side so as to be gently upwardly inclined forward and extends in the width direction DW1 when the feeding tray 3 is in the unfolded position shown in FIG. 1 and the like.

When the feeding tray 3 is in the storage position shown in FIG. 4, the flat plate portion 35 has its forward facing exterior surface flush with the front surface 9S, and constitutes a part of the design surface of the housing 9. The surface of the flat plate portion 35 opposite to the exterior surface is defined as an inner surface 35T.

As shown in FIGS. 1 to 3, the link rails 36A and 36B are located at both ends of the inner surface 35T of the flat plate portion 35 in the width direction DW1, protrude upward, and extend in the feeding direction DF1.

As shown in FIG. 2, the link rail 36A has a groove extending in the feeding direction DF1 from the first rail end 36A1. The link rail 36B has a groove extending in the feeding direction DF1 from the first rail end 36B1.

As shown in FIG. 3, the groove of the link rail 36A extends to a second rail end 36A2 opposite to the first rail end 36A1. The groove of the link rail 36B extends to a second rail end 36B2 opposite to the first rail end 36B1.

As shown in FIG. 2, the sub-tray accommodating portion 37 is located on the inner side in the width direction DW1 with respect to the link rails 36A and 36B on the inner surface 35T side of the flat plate portion 35. As shown in FIG. 4, the sub-tray accommodating portion 37 accommodates the sub-tray 30E with the feed tray 3 in the accommodating position.

As shown in FIG. 1, the sub-tray 30E constitutes a part of the support surface 3A on the upstream side in the feeding direction DF1 by sliding forward when the feeding tray 3 is in the unfolded position.

<Press plate>
As shown in FIGS. 1 to 3, the pressure plate 31 is located on the inner surface 35T side of the feeding tray main body 30. As shown in FIGS. The pressure plate 31 is a substantially flat plate member extending in the feeding direction DF1 and the width direction DW1. The pressure plate 31 has rotation shafts 31A and 31B.

The rotation shafts 31A and 31B are located upstream of the pressure plate 31 in the feeding direction DF1, and protrude toward the outside in the width direction DW1 from two corners separated from each other in the width direction DW1. The rotation axes 31A and 31B are centered on a third axis X3 extending in the width direction DW1.

As shown in FIG. 3, the rotation shaft 31A is supported by the other end 91A2 of the link arm 91A by passing through the groove of the link rail 36A and further passing through the shaft hole of the other end 91A2 of the link arm 91A. ing.

The rotation shaft 31B is supported by the other end 91B2 of the link arm 91B by passing through a groove in the link rail 36B and further passing through a shaft hole in the other end 91B2 of the link arm 91B.

The rotation shafts 31A, 31B are guided by the grooves of the link rails 36A, 36B and can slide between the first rail ends 36A1, 36B1 and the second rail ends 36A2, 36B2 of the link rails 36A, 36B. be.

With this configuration, when the feeding tray 3 is in the storage position shown in FIG. , stands up along the front surface 9S of the housing 9.

Furthermore, when the feeding tray 3 is in the unfolded position shown in FIG. It extends forward from the front surface 9S of the seat 9 and can support the seat SH.

In this state, the upper surface of the pressure plate 31 constitutes a part of the support surface 3A including the downstream end 3D, and supports the sheet SH.

By rotating around the third axis X3, the pressure plate 31 moves to a feeding position where the uppermost sheet SH comes into contact with the feeding roller 21, as shown in FIG. 5, and as shown in FIG. It can move up and down to a non-feeding position below the feeding position.

The position of the pressure plate 31 shown in FIGS. 3, 10, and 12 to 14 is a non-feeding position. The position of the pressure plate 31 shown in FIGS. 6 and 11 is the feeding position.

As shown in FIGS. 2 and 3, the pressure plate 31 integrally has two abutted portions 33. As shown in FIGS. One of the abutted parts 33 is a cylinder that protrudes in one direction in the width direction DW1 from a corner of the pressure plate 31 located downstream in the feeding direction DF1 and on one side in the width direction DW1. The other abutted portion 33 is a cylinder that projects from a corner of the pressure plate 31 located downstream in the feeding direction DF1 and on the other side in the width direction DW1 to the other side in the width direction DW1.

<Transmission shaft, transmission gear, and lifting section>
In order to move the pressure plate 31 up and down between a non-feeding position and a feeding position, the image forming apparatus 1 includes a transmission shaft 51 and two transmission gears 52 shown in FIGS. 3 and 10 to 14, and FIGS. - two elevating parts 60 shown in FIG. 14. Each lifting section 60 has an arm 62A that contacts the pressure plate 31 from below.

As shown in FIGS. 3 and 10, the transmission shaft 51 is a substantially round metal bar located downstream of the pressure plate 31 in the feeding direction DF1 and extending in the width direction DW1. Although not shown, one end of the transmission shaft 51 in the width direction DW1 is connected to a drive source and a transmission mechanism (not shown). The transmission shaft 51 rotates counterclockwise in the drawing of FIG. 10 when driving force is transmitted from a drive source and a transmission mechanism (not shown).

As shown in FIG. 3, each transmission gear 52 and each elevating section 60 constitute two sets. One set of the transmission gear 52 and the elevating part 60 can transmit driving force to the abutted part 33 located on one side of the pressure plate 31 in the width direction DW1. The transmission gear 52 and the elevating portion 60 of the other set are capable of transmitting driving force to the abutted portion 33 located on the other side of the pressure plate 31 in the width direction DW1.

The transmission gear 52 and the lifting section 60 of one set and the transmission gear 52 and the lifting section 60 of the other set have the same configuration with opposite hands. Therefore, the configuration of the transmission gear 52 and the elevating section 60 of one set will be described in detail, and the explanation of the transmission gear 52 and the elevating section 60 of the other set will be omitted.

As shown in FIG. 10, the transmission gear 52 is a fan-shaped gear, and is rotatable integrally with the transmission shaft 51. The transmission gear 52 is urged by a tension coil spring 52S to rotate clockwise in the drawing of FIG.

When driving force is transmitted to the transmission shaft 51 from a drive source and a transmission mechanism (not shown), the transmission gear 52 is integrated with the transmission shaft 51 and rotates counterclockwise in the paper of FIG. 10 against the biasing force of the tension coil spring 52S. and moves from the position shown in FIG. 11 to the position shown in FIG. 10.

As shown in FIGS. 3 and 6 to 9, the elevating section 60 includes a first transmitting section 61, a second transmitting section 62, and a torsion coil spring 69. The torsion coil spring 69 is an example of the "biasing member" of the present invention.

The first transmission section 61 includes a fan-shaped gear 66 and a support plate 61E. The fan-shaped gear 66 is swingable around a first axis X1 extending in the width direction DW1, and meshes with the transmission gear 52. The support plate 61E extends from the fan-shaped gear 66 in the radial direction of the first axis X1 and in the direction approaching the abutted portion 33 of the pressure plate 31.

As shown in FIGS. 8 and 9, the first transmission section 61 includes a bearing 67 and a peripheral wall 68 on the support plate 61E.

The support plate 61E is configured to have a surface perpendicular to a second axis X2 that is parallel to the first axis X1. The bearing 67 is a cylinder that is centered on the second axis X2 and protrudes toward the other side in the width direction DW1 from a surface of the support plate 61E that is orthogonal to the second axis X2. The peripheral wall 68 is a cylinder centered on the second axis X2 and has a larger diameter than the bearing 67, and a portion of the upper side thereof is cut out.

When the transmission gear 52 is in the position shown in FIG. 10, the support plate 61E is located below the first axis X1.

Regarding the swinging direction of the first transmission part 61 around the first axis X1, the direction in which the support plate 61E rises from the position shown in FIG. 10 toward the position shown in FIG. The direction of descent from the position shown in FIG. 11 to the position shown in FIG. 10 is defined as a second direction R2.

The first direction R1 is a direction in which the pressure plate 31 is raised from the non-feeding position to the feeding position. The second direction R2 is a direction in which the pressure plate 31 is lowered from the feeding position to the non-feeding position, and is opposite to the first direction R1.

As shown in FIGS. 8 and 9, the first transmission portion 61 has a recess or notch in a portion located closer to the first axis X1 than the outer circumferential surface of the peripheral wall 68, and one side of the recess or notch. It has a first contact surface 61T, which is a first contact surface 61T, and a retaining surface 61U, which is another surface of the recess or notch.

The first contact surface 61T is a small flat surface facing in the second direction R2. As shown in FIG. 7, the first contact surface 61T can come into contact with a second contact surface 62T of the second transmission section 62, which will be described later.

As shown in FIGS. 8 and 9, the retaining surface 61U is a small flat surface that is perpendicular to the first axis X1 and the second axis X2 and faces in one direction in the width direction DW1.

The second transmission section 62 has the arm 62A of the elevating section 60 as a part thereof, and further includes an opposing plate 62B. The opposing plate 62B is configured to have a substantially circular surface perpendicular to the second axis X2. The opposing plate 62B has a shaft portion 63 centered on the second axis X2. The shaft portion 63 protrudes from the center of the substantially circular surface of the opposing plate 62B toward one side in the width direction DW1.

The bearing 67 of the first transmitting section 61 supports the shaft section 63 in a state where the opposing plate 62B faces the support plate 61E of the first transmitting section 61 in the width direction DW1, so that the second transmitting section 62 It can swing around the axis X2.

In other words, the support plate 61E supports the second transmission section 62 so as to be swingable around the second axis X2 by the bearing 67 at its tip.

The arm 62A has a substantially rod-like shape that extends from the opposing plate 62B in the radial direction of the second axis X2 and in the direction approaching the abutted portion 33 of the pressure plate 31, and reaches a tip 62E. The arm 62A is formed integrally with the opposing plate 62B, and protrudes toward the opposite side of the second axis X2 from the sector gear 66 of the first transmission section 61, that is, toward the front side where the pressure plate 31 is located.

The opposing plate 62B of the second transmission section 62 has an arcuate rib 64. The arcuate rib 64 protrudes from the outer periphery of the opposing plate 62B toward one side in the width direction DW1, extends so as to draw an arc with a larger diameter than the shaft portion 63 about the second axis X2, and extends toward the root of the shaft portion 63. surrounding. The tip edge of the arcuate rib 64 can slide against the tip edge of the peripheral wall 68.

The second transmission portion 62 has a plate-like piece that protrudes from one end in the circumferential direction of the arcuate rib 64 toward one side in the width direction DW1, and a second contact surface that is one surface of a notch that the plate-like piece has. 62T, and a retaining protrusion 62U, which is a protrusion of the plate-like piece.

As shown in FIG. 7, the second contact surface 62T can contact the first contact surface 61T of the first transmission section 61. As shown in FIG. As shown in FIGS. 9 and 10, the retaining protrusion 62U can come into contact with the retaining surface 61U of the first transmission portion 61 from one side in the width direction DW1.

As shown in FIG. 8, the torsion coil spring 69 includes a coil portion 69C, a first extension portion 69A extending from one end of the coil portion 69C, and a second extension portion 69B extending from the other end of the coil portion 69C. have.

As shown in FIG. 9, in the torsion coil spring 69, the bearing 67 passes through the inner circumferential side of the coil portion 69C which is unwound and stores restoring force. 69A engages with the first transmitting section 61, and the second extending section 69B engages with the second transmitting section 62, so that the second extending section 69B is located between the first transmitting section 61 and the second transmitting section 62. .

In this state, the peripheral wall 68 surrounds the bearing 67 and the coil portion 69C. Only a portion of the coil portion 69C is exposed through the cutout portion of the peripheral wall 68. The retaining surface 61U and the retaining protrusion 62U prevent the second transmitting portion 62 from coming off with respect to the first transmitting portion 61.

The torsion coil spring 69 biases the second transmission section 62 in a direction that lowers the tip 62E of the arm 62A of the second transmission section 62. That is, the torsion coil spring 69 biases the second transmission portion 62 so that the first contact surface 61T and the second contact surface 62T contact each other, as shown in FIG.

In FIGS. 10 to 14, the direction in which the torsion coil spring 69 biases the second transmission section 62 around the second axis X2 is clockwise in the drawing.

As shown in FIGS. 10 and 11, the torsion coil spring 69 biases the second transmission portion 62 so that the first contact surface 61T and the second contact surface 62T contact with each other. The transmission section 62 maintains a movable state together with the first transmission section 61.

When the transmission gear 52 is in the position shown in FIG. 10, the tip 62E of the arm 62A of the second transmission part 62 is at a position vertically downward away from the abutted part 33 of the pressure plate 31 in the non-feeding position. It is in.

When the transmission gear 52 is biased by the tension coil spring 52S and rotates clockwise in the paper of FIG. 10, the first transmission section 61 and the second transmission section 62 are moved upwardly and tilted forward, as shown in FIG. 11. oscillates up to. At this time, the tip 62E of the arm 62A of the second transmission section 62 abuts the abutted portion 33 of the pressure plate 31 from below, thereby raising the pressure plate 31 to the feeding position.

That is, when the first transmitting section 61 moves in the first direction R1 with the tip 62E of the arm 62A of the second transmitting section 62 being below the abutted section 33 of the pressure plate 31, the second transmitting section 62 , the tip 62E of the arm 62A contacts the contacted portion 33 from below and moves together with the first transmission portion 61, thereby pushing the pressure plate 31 up to the feeding position.

On the other hand, as the transmission gear 52 rotates counterclockwise in the paper of FIG. 11 against the biasing force of the tension coil spring 52S, the first transmission section 61 and the second transmission section 62 are rotated as shown in FIG. Swing forward to a downward tilting position. At this time, the tip 62E of the arm 62A of the second transmission section 62 descends while contacting the abutted portion 33 of the pressure plate 31 from below, thereby lowering the pressure plate 31 to the non-feeding position, and further It separates from the contact portion 33 downward in the vertical direction.

That is, when the first transmitting section 61 moves in the second direction R2 with the tip 62E of the arm 62A of the second transmitting section 62 being below the abutted section 33 of the pressure plate 31, the second transmitting section 62 , the tip 62E of the arm 62A contacts the contacted portion 33 from below and moves together with the first transmission portion 61, thereby lowering the pressure plate 31 to the non-feeding position.

In this way, the second transmitting section 62 is supported by the first transmitting section 61 so as to be movable along with the movement of the first transmitting section 61 in the first direction R1 and in the second direction R2.

In a normal state, the image forming apparatus 1 is in a positional relationship in which the pressure plate 31 is at the top and the elevating section 60 is at the bottom, as shown in FIGS. 3, 6, 10, and 11. Here, the vertical relationship between the pressure plate 31 and the elevating part 60 is more specifically the relationship between the abutted part 33 of the pressure plate 31 and the tip 62E of the arm 62A of the second transmitting part 62 of the elevating part 60.

However, as shown in FIG. 12, the image forming apparatus 1 does not allow the pressure plate 31 to move up and down, for example, when removing a jammed sheet SH during feeding, or when the operation is suddenly stopped during feeding due to a power outage, etc. When moving, the pressure plate 31 in the non-feeding position enters below the tip 62E of the arm 62A of the second transmission section 62 of the elevating section 60, and the positional relationship is such that the pressure plate 31 is on top and the elevating section 60 is on the bottom. There is a risk that it will reverse.

Note that the position of the elevating unit 60 shown by the two-dot chain line in FIG. This is the position where the elevating portion 60 is no longer restricted by the mechanism and is raised to its highest level by the urging force of the tension coil spring 52S.

<Operation of the second transmission section when the positional relationship is reversed, with the pressure plate at the top and the arm of the lifting section at the bottom>
The second transmission section 62 operates as follows when the positional relationship is reversed, with the pressure plate 31 at the top and the arm 62A of the elevating section 60 at the bottom.

That is, when the arm 62A of the second transmission section 62 of the elevating section 60 moves from above the pressure plate 31 to below the pressure plate 31, the tip 62E of the arm 62A moves from the pressure plate 31 as shown in FIG. By descending while contacting the contact portion 33 from above, an upward pressing force F1 acts on the second transmission portion 62.

Due to this pressing force F1, the torsion coil spring 69 cannot maintain a state in which the second transmission section 62 can move together with the first transmission section 61. As a result, the second transmission section 62 moves so that the second contact surface 62T is separated from the first contact surface 61T. That is, as shown in FIG. 14, the second transmission section 62 resists the biasing force of the torsion coil spring 69 and swings counterclockwise in the drawing. Thereby, the arm 62A of the second transmission section 62 of the elevating section 60 can descend without being hindered by the abutted section 33 of the pressure plate 31.

Then, when the tip 62E of the arm 62A of the second transmission section 62 separates downward from the abutted part 33 of the pressure plate 31 and the arm 62A moves below the pressure plate 31, the second The transmission section 62 swings clockwise in the paper of FIG. 10 due to the biasing force of the torsion coil spring 69, and after returning to the state where the first contact surface 61T and the second contact surface 62T are in contact with each other, the first contact surface 61T and the second contact surface 62T are brought into contact with each other. It moves together with the transmission section 61.

That is, when the first transmitting section 61 moves in the second direction R2 with the arm 62A of the second transmitting section 62 being above the pressure plate 31, the arm 62A is pushed by the abutted part 33 of the pressure plate 31. As a result, the second contact surface 62T moves away from the first contact surface 61T. As a result, the arm 62A of the second transmission section 62 moves to retreat from the pressure plate 31 independently of the first transmission section 61, and when the arm 62A moves below the pressure plate 31, it moves together with the first transmission section 61. Moving.

<Effect>
In the image forming apparatus 1 of the embodiment, as shown in FIGS. 7 to 9, the elevating section 60 includes a first transmitting section 61 and a second transmitting section 62. In other words, the elevating section 60 is divided into two parts.

Therefore, as shown in FIG. 12, after the positional relationship in which the pressure plate 31 is on top and the arm 62A of the elevating section 60 is on the bottom is reversed, such a positional relationship is restored to the original position as shown in FIGS. 13 and 14. Therefore, when the first transmitting part 61 moves in the second direction R2 with the tip 62E of the arm 62A of the second transmitting part 62 being above the abutted part 33 of the pressure plate 31, the arm 62A By being pushed by the contact portion 33, it swings in the counterclockwise direction in the drawings of FIGS. 13 and 14 independently of the first transmission portion 61 and retreats from the pressure plate 31.

As a result, in the elevating section 60, the arm 62A of the second transmitting section 62 can reach below the pressure plate 31 without being obstructed by the pressure plate 31, and then the arm 62A of the second transmitting section 62 reaches the position below the first transmitting section 61. Anomalies can be resolved by moving with them.

Therefore, in the image forming apparatus 1 of the embodiment, even if the positional relationship is reversed, with the pressure plate 31 on top and the elevating part 60 on the bottom, it can be easily restored to its original state, and damage to the pressure plate 31 or the elevating part 60 can be suppressed.

Moreover, this image forming apparatus 1 also has the following effects compared to a configuration in which the pressure plate is divided into two parts and can be retracted from the elevating part without dividing the elevating part into two. That is, in this image forming apparatus 1, the first transmitting section 61 and the second transmitting section 62, which are difficult to see from the outside of the casing 9, do not need to be textured to improve the design surface, and are not divided into two parts. Since the mold for the pressure plate can be easily simplified, manufacturing costs can be reduced. Furthermore, in this image forming apparatus 1, it is difficult for hands or foreign objects to reach the first transmitting section 61 and the second transmitting section 62, so that damage to the elevating section 60 can be suppressed. Further, in this image forming apparatus 1, vibrations generated when the arm 62A of the second transmission section 62 moves independently of the first transmission section 61 and then returns to a state where it moves together with the first transmission section 61 are applied to the pressure plate 31. Since it is difficult to transmit, the sheet SH supported by the pressure plate 31 is hard to shift, and it is possible to suppress conveyance defects of the sheet SH.

Further, in this image forming apparatus 1, as shown in FIG. 8, the elevating section 60 includes a torsion coil spring 69 located between the first transmitting section 61 and the second transmitting section 62. The torsion coil spring 69 biases the second transmission section 62 so that the second transmission section 62 remains movable together with the first transmission section 61. With this configuration, the arm 62A of the second transmission section 62 moves independently of the first transmission section 61 against the torsion coil spring 69 by being pushed by the abutted section 33 of the pressure plate 31, and After retracting from 31, it is biased by torsion coil spring 69, and can return to a movable state together with first transmission section 61 with high reliability.

Furthermore, in this image forming apparatus 1, as shown in FIG. Due to the contact, the movable state together with the first transmission section 61 can be maintained with high reliability.

Further, in this image forming apparatus 1, when the first transmitting section 61 moves in the second direction R2 with the arm 62A of the second transmitting section 62 being above the pressure plate 31, the arm 62A is not covered by the pressure plate 31. By being pushed by the contact portion 33, the second contact surface 62T moves counterclockwise in the drawings of FIGS. 13 and 14 so as to separate from the first contact surface 61T. With this configuration, the arm 62A of the second transmission section 62 can smoothly move independently of the first transmission section 61 when pressed by the pressure plate 31.

Furthermore, in this image forming apparatus 1, as shown in FIG. 6 and FIG. 60 can be prevented from becoming bulky in the width direction DW1.

Further, in this image forming apparatus 1, as shown in FIG. It is supported so as to be swingable around two axes X2. Since the peripheral wall 68 of the first transmission section 61 surrounds the bearing 67 and the coil section 69C, it becomes difficult for a user using the supply tray to visually recognize the coil section 69C of the torsion coil spring 69. It becomes difficult to reach with hands and foreign objects. As a result, this image forming apparatus 1 can suppress deterioration in appearance quality and also suppress damage to the elevating section 60.

Although the present invention has been described above based on examples, it goes without saying that the present invention is not limited to the above-mentioned examples, and can be applied with appropriate modifications without departing from the spirit thereof.

In the embodiment, the sheet feeding device of the present invention is embodied as the image forming apparatus 1, but the present invention is not limited to this configuration. For example, the configuration of the present invention may be applied to an image reading device that reads an image on a sheet, or the configuration of the present invention may be applied to an image forming device or an image reading device in a multifunction machine equipped with an image reading device above an image forming device. configuration may be applied.

In the embodiment, the second transmission section 62 moves independently of the first transmission section 61 by swinging around the second axis X2 parallel to the width direction DW1, but the present invention is not limited to this configuration. For example, the axes around which the second transmission section swings may intersect in the width direction. Further, the second transmission section may move independently of the first transmission section by linear movement in the width direction or linear movement in a direction crossing the width direction.

In the embodiment, the biasing member is a torsion coil spring 69, but the present invention is not limited to this configuration. For example, the biasing member may be an elastic body such as a tension coil spring, a compression coil spring, or rubber.

1... Sheet feeding device (image forming device), SH... Sheet 21... Feeding roller, 3... Feeding tray, 31... Pressure plate 60... Lifting section, R1... First direction, R2... Second direction 61... First Transmission part, 62...Second transmission part, 62A...Arm 69...Biasing member (torsion coil spring), 61T...First contact surface 62T...Second contact surface, DW1...Width direction of feeding tray X1... First axis, 66... Fan-shaped gear, 61E... Support plate, X2... Second axis 62B... Opposing plate, 69C... Coil part of torsion coil spring 67... Bearing, 68... Surrounding wall

Claims (6)

a feeding roller that feeds the sheet;
A feeding tray that supports sheets, and a pressure plate that can move up and down is provided at a feeding position where the uppermost sheet comes into contact with the feeding roller and at a non-feeding position below the feeding position. the feeding tray having;
an elevating part that has an arm that contacts the pressure plate from below and is movable to move the pressure plate up and down,
The lifting unit is movable in a first direction in which the pressure plate is raised from the non-feeding position to the feeding position and in a second direction in which the pressure plate is lowered from the feeding position to the non-feeding position. a first transmission section;
a second transmission section having the arm and supported by the first transmission section so as to be movable with the movement of the first transmission section in the first direction and the movement in the second direction;
When the first transmission section moves in the first direction with the arm located below the pressure plate, the arm of the second transmission section contacts the pressure plate from below and moves the first transmission section. pushing the pressure plate up to the feeding position,
When the first transmission section moves in the second direction while the arm is below the pressure plate, the arm of the second transmission section contacts the pressure plate from below and moves the first transmission section. lowering the pressure plate to the non-feeding position by moving with the
When the first transmitting section moves in the second direction with the arm above the pressure plate, the arm of the second transmitting section is pressed by the pressure plate and thereby moves with the first transmitting section. The sheet feeding device is characterized in that the arm is configured to move independently to retreat from the pressure plate, and to move together with the first transmission unit when the arm moves below the pressure plate. The elevating part is located between the first transmitting part and the second transmitting part, and moves the second transmitting part so that the second transmitting part remains movable together with the first transmitting part. The sheet feeding device according to claim 1, further comprising a biasing member that biases the sheet. The first transmission part faces the second direction and has a first contact surface that can come into contact with the second transmission part,
The second transmission part has a second contact surface that can come into contact with the first contact surface,
3. The sheet feeding device according to claim 2, wherein the biasing member biases the second transmission section so that the first contact surface and the second contact surface come into contact with each other. When the first transmission section moves in the second direction while the arm is above the pressure plate, the arm of the second transmission section is pressed by the pressure plate and thereby contacts the second contact surface. The sheet feeding device according to claim 3, wherein the sheet feeding device moves so as to move away from the first contact surface. The first transmission section includes a fan-shaped gear that is swingable around a first axis that extends in the width direction of the feeding tray, and a fan-shaped gear that extends from the fan-shaped gear in a radial direction of the first axis, and that is connected to the a support plate that supports the second transmission part so as to be swingable around a second axis parallel to the first axis;
The second transmission section further includes a facing plate that faces the support plate and is supported by the support plate so as to be swingable around the second axis,
5. The sheet feeding device according to claim 2, wherein the arm extends from the opposing plate in a radial direction of the second axis. The biasing member is a torsion coil spring,
The support plate passes through the inner peripheral side of the coil portion of the torsion coil spring and supports the second transmission portion so as to be swingable around the second axis;
The sheet feeding device according to claim 5, further comprising a peripheral wall surrounding the bearing and the coil portion.

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