JP6299686B2 - Sheet cassette and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a sheet feeding cassette and an image forming apparatus including the same.

  The image forming apparatus includes a paper feed cassette that stores paper (sheets). The paper feed cassette is provided with a lift plate that lifts the paper toward the paper feed roller.

  The lift plate is configured to move up and down on the downstream side with the upstream side in the paper supply direction as a fulcrum. Here, when the paper feeding cassette (or the image forming apparatus storing the paper feeding cassette) is transported, the lift plate may vibrate vigorously and collide with the peripheral members. At this time, there arises a problem that the lift plate itself and peripheral members are damaged.

  Techniques for solving the above problems have been proposed. For example, the paper feed cassette described in Patent Document 1 includes a cassette frame, a lift plate, and a pair of width direction cursors. The pair of width direction cursors performs positioning in the width direction of the paper on the lift plate, and includes a lift plate engagement hole. The lift plate has a pair of cursor engaging projections protruding toward the width direction cursor. When each width direction cursor is brought close to the lift plate with the lift plate lowered, each cursor engagement protrusion is inserted into each lift plate engagement hole. Thereby, a lift board will be in a locked state.

  Further, the paper feed cassette described in Patent Document 1 includes a cursor position detection unit so as not to start paper feed with the lift plate locked. The cursor position detecting means is disposed at the bottom of the cassette frame and detects that the width direction cursor exists at the lift plate lock position.

JP 2005-170575 A

  However, the paper feed cassette described in Patent Document 1 may unintentionally lock the lift plate when each width direction cursor is operated for replenishment of paper. That is, the user may accidentally lock the lift plate during normal use. As a countermeasure against this, the paper feed cassette described in Patent Document 1 needs to add a cursor position detecting means so as not to move the lift plate in the locked state up and down. For this reason, the paper feed cassette described in Patent Document 1 has a problem that the structure of the paper feed cassette becomes complicated and the manufacturing cost increases. Further, the cursor position detecting means cannot prevent the lift plate from being locked due to an error.

  In order to solve the above-described problems, the present invention provides a paper feed cassette that prevents the lift plate from being erroneously fixed, and an image forming apparatus including the same.

  In order to achieve the above-described object, a sheet feeding cassette according to the present invention includes a cassette body formed to be capable of accommodating sheets, a lowered position along a bottom portion of the cassette body, and a sheet spaced apart upward from the bottom portion. A lift plate provided so as to be able to move up and down between the raised position enabling the conveyance of the cassette and a bottom plate of the cassette body, the lift plate being provided so as to be movable in a direction in contact with and away from the lift plate. A cursor that regulates the position of the sheet to be placed, and the lift plate is provided so as to be displaceable from a lowered position to a depressed position, and the cursor is displaced to the depressed position. It has an engaging portion that engages with an engaged portion formed on the lift plate and fixes the lift plate at the pushed-down position when moved to contact with the lift plate.

  In this case, it further includes an elastic member that is disposed between the bottom portion of the cassette body and the lower surface of the lift plate and supports the lift plate displaced to the lowered position, and the lift plate elastically supports the elastic member. It is preferable to displace to a push-down position that is further lowered from the lowered position by being deformed.

  According to these configurations, in order to engage the engaging portion of the cursor with the engaged portion of the lift plate, the lift plate needs to be pushed down from the lowered position to the pushed down position. For this reason, for example, when the cursor is moved to the lift plate side during normal use for regulating the seat position, the engaging portion of the cursor may be engaged with the engaged portion of the lift plate at the lowered position. Absent. Thereby, it can prevent that a lift board is fixed accidentally at the time of normal use. Therefore, since it is not necessary to detect the position of the cursor, the configuration of the paper feed cassette can be simplified and the manufacturing cost can be reduced.

  In this case, it is preferable that the cursor includes a pair of width direction cursors that align both ends in the width direction orthogonal to the sheet supply direction.

  In this case, it is preferable that the cursor includes a length direction cursor that aligns one end of the sheet in the supply direction.

  According to these configurations, the cursor (each width direction cursor or / and the length direction cursor) can appropriately position the sheet on the lift plate during normal use and, for example, pushes the lift plate during transportation. It can be locked in the lowered position.

  In this case, the length direction cursor can be changed in posture between a standing posture capable of coming into contact with one end portion of the sheet feeding direction and a lying posture falling to the lift plate side along the bottom portion of the cassette body. The engaging portion is formed on an upper end surface of the length direction cursor, and is engaged with the engaged portion of the lift plate when the length direction cursor is changed to the lying posture. It is preferable to combine them.

  According to this configuration, the length direction cursor is normally used by being in the standing posture, and the lift plate can be locked by changing the posture from the standing posture to the lying posture. Therefore, it is possible to reliably prevent the length direction cursor (the engaging portion) normally used in the standing posture from engaging the engaged portion of the lift plate. Further, when the length direction cursor is in the lying posture, the length in the sheet supply direction in the cassette body is increased by the thickness of the length direction cursor. Thus, a large sheet that cannot be accommodated during normal use can be accommodated in the cassette body.

  In this case, it is preferable that the engaging portion is recessed on the lift plate side of the cursor so as to fit an end portion of the lift plate as the engaged portion.

  According to this configuration, the lift plate is locked at the pushed-down position by fitting the end portion of the lift plate into the engagement portion provided in a state where the lift plate is recessed in the cursor. Therefore, it is not necessary to separately form an engaged portion such as a protrusion on the lift plate, so that the manufacturing cost of the lift plate can be reduced.

  In order to achieve the above-described object, an image forming apparatus of the present invention includes any of the above-described paper feed cassettes.

  According to this configuration, in order to engage the engaging portion of the cursor with the engaged portion of the lift plate, the lift plate needs to be pushed down from the lowered position to the pushed down position. For this reason, the engaging portion of the cursor does not engage with the engaged portion of the lift plate at the lowered position. Thereby, it can prevent that a lift board is fixed accidentally at the time of normal use.

  According to the present invention, it is possible to prevent the lift plate from being erroneously fixed in the paper feed cassette.

1 is a front view schematically showing an internal structure of a color printer according to an embodiment of the present invention. It is a perspective view which shows the paper feed cassette which concerns on one Embodiment of this invention. It is a top view which shows typically the paper feed cassette which concerns on one Embodiment of this invention. It is IV-IV sectional drawing of FIG. It is VV sectional drawing of FIG. It is a top view explaining the effect | action of the paper feed cassette which concerns on one Embodiment of this invention. It is a top view explaining the lock | rock procedure of the lift board of the paper feed cassette which concerns on one Embodiment of this invention. It is sectional drawing which shows typically the lift board and width direction cursor of the paper feed cassette which concern on one Embodiment of this invention. It is sectional drawing which shows typically the lift board and length direction cursor of the paper feed cassette which concern on one Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the front side of the sheet of FIG. 1 is the front surface (front surface), and the other directions will be described as a reference.

  A color printer 1 as an image forming apparatus according to the present embodiment will be described with reference to FIG. FIG. 1 is a front view schematically showing the internal structure of the color printer 1.

  The color printer 1 includes an apparatus main body 2, a paper feed cassette 3, and a paper discharge tray 4. The apparatus main body 2 is formed in a substantially box shape. The paper feed cassette 3 is provided in the lower part of the apparatus main body 2. The paper discharge tray 4 is provided in the upper part of the apparatus main body 2.

  Although details will be described later, a sheet S (a bundle) is accommodated in the sheet feeding cassette 3. The paper feed cassette 3 is detachably attached to a mounting portion 2 a provided at the lower part of the apparatus main body 2. The sheet S is not limited to paper and may be a resin film or the like.

  The color printer 1 includes a paper feeding unit 10, an image forming unit 11, and a fixing device 12 inside the apparatus main body 2. The paper feed unit 10 is provided on the upstream side of the conveyance path 5 extending from the paper feed cassette 3 to the paper discharge tray 4. The image forming unit 11 is provided in an intermediate portion of the conveyance path 5. The fixing device 12 is provided on the downstream side of the conveyance path 5.

  The paper feed unit 10 includes a pickup roller 10 a and a transport roller pair 10 b for sending the sheets S stored in the paper feed cassette 3 one by one to the transport path 5.

  The image forming unit 11 includes four toner containers 15, an intermediate transfer belt 16, four drum units 17, and an optical scanning device 18. The four toner containers 15 are juxtaposed in the left-right direction below the paper discharge tray 4. The intermediate transfer belt 16 is provided on the lower side of each toner container 15 so as to be able to run in the direction of a white arrow. The four drum units 17 are juxtaposed in the left-right direction below the intermediate transfer belt 16. The optical scanning device 18 is disposed below each drum unit 17.

  The four toner containers 15 contain toner (developer) of four colors (yellow, magenta, cyan, black). The four drum units 17 are provided corresponding to the toners of the respective colors. Since the four drum units 17 have substantially the same structure, only one drum unit 17 will be described below.

  The drum unit 17 includes a photoconductor drum 20, a charging device 21, a developing device 22, a primary transfer roller 23, and a cleaning device 24. The photosensitive drum 20 is in contact with the lower side of the intermediate transfer belt 16. The charging device 21, the developing device 22, the primary transfer roller 23, and the cleaning device 24 are arranged around the photosensitive drum 20 in the order of the transfer process. The primary transfer roller 23 is disposed above the photosensitive drum 20 with the intermediate transfer belt 16 interposed therebetween. On the right side of the intermediate transfer belt 16, a secondary transfer roller 25 that forms a secondary transfer nip portion 25a is disposed.

  Here, the operation of the color printer 1 will be described. A control device (not shown) executes image forming processing based on the input image data as follows.

  Each charging device 21 charges the surface of each photosensitive drum 20. The optical scanning device 18 performs exposure corresponding to the image data (see broken line arrows in FIG. 1) toward each photosensitive drum 20. Each developing device 22 develops the electrostatic latent image formed on the surface of each photosensitive drum 20 into a toner image. The four toner images carried on each photoconductor drum 20 are primary-transferred in order to the traveling intermediate transfer belt 16 by a primary transfer roller 23 to which a primary transfer bias is applied. As a result, a full-color toner image is formed on the surface of the intermediate transfer belt 16.

  On the other hand, the sheet S supplied from the paper feed cassette 3 is transported through the transport path 5 and passes through the secondary transfer nip portion 25a. The full-color toner image is secondarily transferred to the sheet S by the secondary transfer roller 25 to which a secondary transfer bias is applied. The fixing device 12 fixes the toner image on the sheet S. The sheet S after the fixing process is discharged to the paper discharge tray 4. Each cleaning device 24 removes toner remaining on the surface of each photoconductive drum 20 after transfer.

  Next, the paper feed cassette 3 according to the present embodiment will be described with reference to FIGS. 1 to 5. FIG. 2 is a perspective view showing the paper feed cassette 3. FIG. 3 is a plan view schematically showing the paper feed cassette 3. 4 is a cross-sectional view taken along the line IV-IV in FIG. 5 is a cross-sectional view taken along the line VV in FIG. In the following description, the term “supply direction” refers to the supply (feed) direction of the sheet S, and the term “width direction” refers to the width direction of the sheet S orthogonal to the supply direction. In addition, “upstream” and “downstream” and similar terms refer to “upstream” and “downstream” in the feed direction and similar concepts.

  As shown in FIGS. 1 and 2, the paper feed cassette 3 is roughly formed in a substantially rectangular parallelepiped shape that is flat in the vertical direction. The paper feed cassette 3 is mounted so as to be able to be taken in and out of the mounting portion 2a through an opening (not shown) on the lower front surface of the apparatus main body 2.

  The paper feed cassette 3 includes a cassette body 30, a lift plate 31, an elevating device 32, an elastic member 33, a pair of front and rear width direction cursors 34, and a length direction cursor 35. The cassette body 30 is formed so as to accommodate the sheet S. The lift plate 31 is provided on the bottom portion 30a of the cassette body 30 so as to be movable up and down. The elevating device 32 is provided to move the lift plate 31 in the vertical direction. The elastic member 33 is disposed between the bottom 30 a of the cassette body 30 and the lower surface of the lift plate 31. A pair of front and rear width direction cursors 34 is provided to align both ends of the sheet S in the width direction. The length direction cursor 35 is provided to align the upstream end of the sheet S in the supply direction.

  As shown in FIGS. 2 and 3, the cassette body 30 is formed in a substantially rectangular box shape with the upper surface opened. Movable rails 40 are respectively attached to the left and right side surfaces of the cassette body 30 (see also FIG. 1). The pair of left and right movable rails 40 are slidably engaged with a pair of left and right fixed rails (not shown) extending in the front-rear direction in the mounting portion 2a. Thereby, the cassette body 30 (paper feed cassette 3) is supported so as to be slidable in the front-rear direction in the mounting portion 2a. At the front part of the cassette body 30, a panel part 41 constituting the lower front surface of the apparatus body is provided. On the front surface of the panel portion 41, a grip portion 42 is provided that is gripped by the user when being inserted into and removed from the mounting portion 2a.

  A pair of front and rear width direction guide grooves 43 and a length direction guide groove 44 are formed on the bottom 30 a of the cassette body 30. Each width direction guide groove 43 extends in the front-rear direction (width direction) on the right side (downstream in the supply direction) of the bottom portion 30a. The length direction guide groove 44 extends in the left-right direction (supply direction) at the center in the front-rear direction of the bottom 30a.

  The lift plate 31 is, for example, a flat plate member made of metal, and is disposed on the right side (downstream in the supply direction) on the bottom 30 a of the cassette body 30. A sheet S (bundle) is placed on the upper surface of the lift plate 31 (see also FIG. 1). In the lift plate 31, a pair of front and rear width-direction notches 50 and a length-direction notch 51 are formed in the movement range of the cursors 34 and 35.

  The pair of left and right width-direction notches 50 are cut from the front and rear end portions of the lift plate 31 toward the front and rear direction center, and are formed in a rectangular shape in plan view. Each width direction guide groove 43 described above is exposed in each width direction notch 50. The lengthwise cutout 51 is cut from the left end of the lift plate 31 to the right between the pair of left and right widthwise cutouts 50 and is formed in a rectangular shape in plan view. The length direction guide groove 44 described above extends to the length direction notch 51.

  A pair of front and rear plate rotation shafts 52 that are pivotally supported on both front and rear inner surfaces of the cassette body 30 are provided at the left end portion (upstream end portion in the supply direction) of the lift plate 31 (see FIGS. 1 and 2). . The lift plate 31 is supported by the cassette body 30 so as to rotate in the vertical direction about each plate rotation shaft 52. Specifically, the lift plate 31 has a lowered position P1 (see FIG. 2) along the bottom 30a of the cassette body 30 and a raised position P2 (see FIG. 1) that allows the sheet S to be conveyed away from the bottom 30a. Reference) and can be moved up and down.

  As shown in FIGS. 1 and 3, the lifting device 32 is disposed on the right side (downstream side) of the cassette body 30. The lifting device 32 includes a lifting shaft 32a and a push-up plate 32b.

  The elevating shaft 32a is supported on the bottom 30a of the cassette body 30 so as to be rotatable about an axis. The elevating shaft 32a extends from the rear part of the cassette body 30 to the center part in the front-rear direction. The rear end portion of the elevating shaft 32 a protrudes on the back side of the cassette body 30. A motor joint (not shown) is provided at the rear end of the elevating shaft 32a. The motor coupling portion is connected to an output shaft of a lift motor (not shown) provided in the apparatus main body 2 when the paper feed cassette 3 is set in the mounting portion 2a. The push-up plate 32b is fixed to the front end portion of the elevating shaft 32a and extends to the right side. The push-up plate 32b is formed in a rectangular shape in plan view, and is disposed at the center in the front-rear direction of the cassette body 30.

  The control device drives and controls a lift motor and the like in the execution process of the image forming process. The lift motor rotates the elevating shaft 32a and the push-up plate 32b counterclockwise in FIG. The push-up plate 32b engages with the lower surface of the lift plate 31 at the lowered position P1, and pushes up the downstream end of the lift plate 31. That is, the lift plate 31 rises from the lowered position P1 to the raised position P2 (see FIG. 1). As a result, the uppermost layer of the sheet S on the lift plate 31 comes into contact with the pickup roller 10a of the sheet feeding unit 10, and the sheet feeding unit 10 (the pickup roller 10a and the conveyance roller pair 10b) separates the sheets S one by one. Is sent out toward the conveyance path 5 (see the arrow in FIG. 1). When the supply of the sheet S is completed, the lift motor is controlled by the control device to rotate the elevating shaft 32a and the push-up plate 32b clockwise in FIG. That is, the lift plate 31 is lowered from the raised position P2 to the lowered position P1 (see FIG. 2). When the paper feed cassette 3 is pulled out from the mounting portion 2a, the lift shaft 32a is disconnected from the lift motor, so that the lift plate 31 is displaced to the lowered position P1.

  As shown in FIGS. 3 and 4, the elastic member 33 is formed in a substantially rectangular parallelepiped shape with an elastically deformable material such as urethane sponge. For example, the elastic member 33 is divided and fixed in two in the front-rear direction on the lower right side surface of the lift plate 31. The elastic member 33 supports the lift plate 31 that is displaced to the lowered position P1 while absorbing the impact when the elastic member 33 is lowered from the raised position P2 to the lowered position P1. The elastic member 33 has rigidity capable of supporting the lift plate 31 displaced to the lowered position P1 in a state where the sheets S are fully loaded.

  Although the details will be described later, the lift plate 31 described above is provided so as to be displaceable from the lowered position P1 to the pushed-down position P0 that is further lowered by elastically deforming the elastic member 33 (see FIG. 8). The elastic member 33 may be divided into three or more or may not be divided. The elastic member 33 may be fixed to the bottom 30a of the cassette body 30. The elastic member 33 is not limited to urethane sponge, and may be, for example, a compression coil spring or rubber.

  As shown in FIGS. 2 and 3, the pair of front and rear width direction cursors 34 is formed in a substantially rectangular parallelepiped shape that is long in the left-right direction. A contact surface 34 a is formed on each of the opposing side surfaces of the pair of front and rear width direction cursors 34. The pair of front and rear width direction cursors 34 is arranged in the pair of front and rear width direction notches 50 of the lift plate 31. Each width direction cursor 34 is slidably engaged with the width direction guide groove 43 of the cassette body 30. That is, the pair of front and rear width direction cursors 34 is provided to be movable in the front and rear direction (width direction) at the bottom 30 a of the cassette body 30. The pair of front and rear width direction cursors 34 are opposed to each other with the lift plate 31 interposed therebetween, and are connected to an interlocking mechanism 60 such as a rack and pinion. The pair of front and rear width direction cursors 34 moves evenly from the center in the width direction by the action of the interlocking mechanism 60.

  As shown in FIG. 4, first engaging grooves 61 are respectively provided below the contact surfaces 34 a of the pair of front and rear width direction cursors 34. The first engaging groove 61 as an engaging portion is recessed in the left-right direction (supply direction) of the contact surface 34a (see FIG. 3). Each first engagement groove 61 is formed below the lift plate 31 at the lowered position P1. The width (vertical distance) of each first engagement groove 61 is slightly larger than the thickness of the lift plate 31.

  As shown in FIGS. 3 and 4, the lift plate 31 is formed with a pair of front and rear first engaged portions 53 that can be engaged with the first engagement grooves 61 of the pair of front and rear width direction cursors 34. ing. The pair of front and rear first engaged portions 53 is configured by an end portion (edge portion) of the lift plate 31 that opposes the contact surface 34a of each width direction cursor 34 (see an alternate long and short dash line ellipse in FIG. 3). That is, the pair of front and rear first engaged portions 53 is formed at an edge portion on one side in the width direction center side that constitutes each width direction cutout portion 50.

  As shown in FIGS. 3 and 5, the length direction cursor 35 includes a cursor sliding portion 70 and a cursor contact portion 71. The cursor sliding portion 70 is slidably engaged with the longitudinal guide groove 44 of the cassette body 30. That is, the length direction cursor 35 is provided so as to be movable in the left-right direction (supply direction) at the bottom 30 a of the cassette body 30. Since the length direction guide groove 44 extends into the length direction cutout portion 51 of the lift plate 31, the cursor sliding portion 70 is configured to be able to enter the length direction cutout portion 51. Yes.

  As shown in FIG. 5, the cursor contact portion 71 is connected to the left end portion of the cursor sliding portion 70 via a cursor rotation shaft 72. The cursor contact portion 71 is provided so as to be rotatable about a cursor rotation shaft 72. The cursor contact portion 71 includes a standing posture P11 that can contact the upstream side (one end portion) of the sheet S in the supply direction, and a lying posture P12 that falls to the lift plate 31 side along the bottom portion 30a of the cassette body 30. The posture can be changed between.

  A second engagement groove 73 is formed on the upper end surface 71a of the cursor contact portion 71 whose posture has been changed to the standing posture P11. The second engaging groove 73 as the engaging portion is recessed in the front-rear direction (width direction) of the upper end surface 71a. When the posture of the cursor contact portion 71 is changed to the lying posture P12, the second engagement groove 73 is formed below the lift plate 31 at the lowered position P1. The width (distance in the vertical direction) of the second engagement groove 73 is slightly larger than the thickness of the lift plate 31.

  As shown in FIG. 3, the above-described lift plate 31 is formed with a second engaged portion 54 that can be engaged with the second engagement groove 73 of the length direction cursor 35. The second engaged portion 54 is configured by an end portion (edge portion) of the lift plate 31 facing the cursor contact portion 71 whose posture has been changed to the standing posture P11 (see the two-dot chain line ellipse in FIG. 3). That is, the second engaged portion 54 is formed at the edge portion of the right side that constitutes the longitudinal cutout portion 51.

  Next, operations of the lift plate 31, the width direction cursors 34, and the length direction cursor 35 will be described with reference to FIGS. FIG. 6 is a plan view for explaining the operation of the paper feed cassette 3. FIG. 7 is a plan view for explaining the locking procedure of the lift plate 31. FIG. 8 is a cross-sectional view schematically showing the lift plate 31 and the width direction cursor 34. FIG. 9 is a cross-sectional view schematically showing the lift plate 31 and the length direction cursor 35.

  First, a case where the cursors 34 and 35 are normally used will be described. The user stacks the sheet S (bundle) on the lift plate 31 in a state where the sheet feeding cassette 3 is pulled out from the apparatus main body 2 (mounting portion 2a). As described above, the lift plate 31 is in the lowered position P1 when the paper feed cassette 3 is pulled out from the apparatus main body 2.

  Subsequently, as shown in FIG. 6, the user moves the pair of front and rear width direction cursors 34 in the width direction to bring the contact surfaces 34 a into contact with both ends in the width direction of the sheet S on the lift plate 31. In addition, the user moves the length direction cursor 35 in the supply direction while changing the posture of the cursor contact portion 71 to the standing posture P11, and the cursor contacts the upstream end of the sheet S on the lift plate 31 in the supply direction. The part 71 is brought into contact. As described above, the pair of front and rear width direction cursors 34 and the length direction cursor 35 regulate the position of the sheet S placed on the lift plate 31. Thereby, the sheet S can be positioned at an appropriate position.

  Next, the user attaches the paper feed cassette 3 to the attachment portion 2a. The control device detects the attachment of the paper feed cassette 3 and controls the drive of the lift motor. Then, as already described, the lift plate 31 is lifted from the lowered position P1 to the raised position P2, and the uppermost layer of the sheet S is brought into contact with the pickup roller 10a (see FIG. 1). Thereby, the supply preparation of the sheet S is completed.

  Here, it is considered to transport the sheet cassette 3 alone or with the sheet cassette 3 mounted on the apparatus main body 2. In the paper feed cassette 3 according to the present embodiment, the lift plate 31 is fixed to the cursors 34 and 35 so as not to vibrate violently during transportation. Hereinafter, a procedure for locking the lift plate 31 will be described.

  First, the user pulls out the paper feed cassette 3 from the apparatus main body 2 and removes the sheet S on the lift plate 31. At this time, the lift plate 31 is in the lowered position P1. Subsequently, as shown in FIG. 7, the user moves each width direction cursor 34 in a direction approaching the lift plate 31. Next, as shown in FIG. 8, the user pushes down the lift plate 31 while elastically deforming the elastic member 33. As a result, the lift plate 31 is displaced from the lowered position P1 to the pressed position P0. Next, the user moves each width direction cursor 34 so as to contact the lift plate 31 displaced to the pressed position P0. Then, the pair of front and rear first engaged portions 53 of the lift plate 31 are fitted in the first engagement grooves 61 of the pair of front and rear width direction cursors 34.

  Next, as shown in FIG. 9, the user changes the posture of the cursor contact portion 71 of the length direction cursor 35 from the standing posture P11 to the lying posture P12. The cursor contact portion 71 whose posture has been changed to the lying posture P12 forms substantially the same plane as the upper surface of the lift plate 31. Thereby, the upper surface of the cursor contact portion 71 whose posture has been changed to the lying posture P12 can be used as the placement surface of the sheet S. The user moves the cursor contact portion 71 in the lying posture P12 to contact the lift plate 31 displaced to the pressed position P0. Then, the second engaged portion 54 of the lift plate 31 is fitted into the second engagement groove 73 of the length direction cursor 35 (cursor contact portion 71).

  As described above, the lift plate 31 is held at the pressed position P0 and is in a locked state in which the rotation is restricted. Each width direction cursor 34 and length direction cursor 35 can appropriately position the sheet S on the lift plate 31 during normal use, and for example, lock the lift plate 31 at the push-down position P0 during transportation. Can do. Thereby, since the vibration of the lift plate 31 during transportation can be prevented, damage to the lift plate 31 itself and peripheral members can be prevented.

  As described above, the pair of width direction cursors 34 and length direction cursors 35 are provided so as to be movable in a direction in contact with and away from the lift plate 31. When each width direction cursor 34 moves until it comes into contact with the lift plate 31 displaced to the pressed position P0, it engages with the first engaged portion 53 to fix the lift plate 31 to the pressed position P0. One engaging groove 61 is provided. Similarly, the length direction cursor 35 has a second engagement groove 73 that engages with the second engaged portion 54 and fixes the lift plate 31 to the pressed position P0. According to the paper feed cassette 3 according to the present embodiment described above, in order to engage the engaging grooves 61 and 73 of the cursors 34 and 35 with the engaged portions 53 and 54 of the lift plate 31, It is necessary to push down the lift plate 31 from the lowered position P1 to the pushed position P0. Therefore, for example, when the cursors 34 and 35 are normally used, the engagement grooves 61 and 73 of the cursors 34 and 35 are formed in the engaged portions 53 and 54 of the lift plate 31 at the lowered position P1. There is no engagement. Thereby, it can prevent that the lift board 31 is fixed accidentally at the time of normal use. Therefore, since the position detection of each cursor 34 and 35 becomes unnecessary, the structure of the paper feed cassette 3 can be simplified and the manufacturing cost can be reduced.

  Further, the second engagement groove 73 engages with the second engaged portion 54 of the lift plate 31 when the posture of the cursor contact portion 71 of the length direction cursor 35 is changed to the lying posture P12. According to the sheet feeding cassette 3 as described above, the length direction cursor 35 (cursor contact portion 71) is normally used when the standing posture P11 is set, and the posture is changed from the standing posture P11 to the lying posture P12. The lift plate 31 can be locked. Therefore, it is possible to reliably prevent the second engagement groove 73 of the length direction cursor 35 normally used in the standing posture P11 from being engaged with the second engaged portion 54 of the lift plate 31. Further, when the length direction cursor 35 (cursor contact portion 71) is in the lying posture P12, the length in the supply direction in the cassette body 30 is increased by the thickness of the length direction cursor 35. Thereby, a large sheet S that cannot be accommodated during normal use can be accommodated in the cassette body 30.

  The engagement grooves 61 and 73 are recessed on the lift plate 31 side of the cursors 34 and 35 so that the end portions (edge portions) of the lift plate 31 as the engaged portions 53 and 54 are fitted. Has been. According to such a sheet feeding cassette 3, the lift plate 31 has the engagement grooves 61 and 73 provided in a state where the end portions (respective engaged portions 53 and 54) are recessed in the cursors 34 and 35. Is locked at the pressed position P0. Therefore, for example, since it is not necessary to separately form an engaged portion such as a protrusion on the lift plate 31, the manufacturing cost of the lift plate 31 can be reduced.

  In the procedure for locking the lift plate 31 described above, the length direction cursor is set after the first engaged portions 53 of the lift plate 31 are fitted in the first engagement grooves 61 of the width direction cursors 34. Although the second engaged portion 54 of the lift plate 31 is fitted in the second engaging groove 73 of 35, the order of fitting may be reversed. Further, in the procedure of locking the lift plate 31 described above, all the engaged portions 53 and 54 are fitted in all the engaging grooves 61 and 73, but the present invention is not limited to this. Each first engagement groove 61 or second engagement groove 73 only needs to be engaged with an end portion of each lift plate 31 (each first engaged portion 53 or second engaged portion 54).

  In the paper feed cassette 3 according to the present embodiment, the engaging grooves 61 and 73 are formed in all the cursors 34 and 35, but the present invention is not limited to this. For example, the second engagement groove 73 may be deleted from the length direction cursor 35 and only the first engagement groove 61 of each width direction cursor 34 may be provided. Further, for example, the first engagement groove 61 may be deleted from each width direction cursor 34 and only the second engagement groove 73 of the length direction cursor 35 may be provided.

  In the paper feed cassette 3 according to the present embodiment, the engagement grooves 61 and 73 are recessed in the cursors 34 and 35, but the present invention is not limited to this. Although illustration is omitted, for example, instead of the engagement grooves 61 and 73, engagement holes as engagement portions may be formed in the cursors 34 and 35. In this case, the lift plate 31 is formed with a projection (engaged portion) that can be fitted into each engagement hole. Further, for example, instead of the respective engaging grooves 61 and 73, an engaging protrusion as an engaging portion or a protruding ridge portion extending in the left-right direction may be provided. In this case, the lift plate 31 is formed with holes and grooves (engaged portions) for fitting the respective engagement protrusions and the ridges.

  Although the length direction cursor 35 of the paper feed cassette 3 according to the present embodiment is provided so as to be rotatable around the cursor rotation shaft 72, the present invention is not limited to this. Although illustration is omitted, for example, the length direction cursor 35 may be configured not to rotate. In this case, it is preferable that the second engagement groove 73 is recessed at the lower portion of the cursor contact portion 71.

  The paper feed cassette 3 according to the present embodiment includes the lift plate 31 that rotates about each plate rotation shaft 52, but the present invention is not limited to this. For example, the lift plate may be configured to translate in the vertical direction.

  In the present embodiment, the case where the present invention is applied to the color printer 1 has been described as an example. However, the present invention is not limited to this, and the present invention may be applied to, for example, a monochrome printer, a facsimile machine, and a copying machine.

  The description of the above embodiment shows one aspect of the paper feed cassette and the image forming apparatus including the same according to the present invention, and the technical scope of the present invention is not limited to the above embodiment. . The components in the above embodiment can be appropriately replaced or combined with existing components and the like, and the description of the above embodiment does not limit the content of the invention described in the claims. .

1 Color printer (image forming device)
2 apparatus main body 3 paper feed cassette 30 cassette main body 30a bottom 31 lift plate 33 elastic member 34 width direction cursor (cursor)
35 Length direction cursor (cursor)
53 First engaged portion (engaged portion)
54 Second engaged portion (engaged portion)
61 1st engagement groove (engagement part)
71a Upper end surface 73 2nd engagement groove (engagement part)
P0 Depressed position P1 Lowered position P2 Elevated position P11 Standing posture P12 Falling posture S Seat

Claims (7)

A cassette body formed to be capable of accommodating a sheet;
A lift plate provided so as to be able to move up and down between a lowered position along the bottom of the cassette body and a raised position that is spaced upward from the bottom to enable conveyance of the sheet;
A cursor that is movably provided in a direction in contact with and away from the lift plate at the bottom of the cassette body, and that regulates the position of the sheet placed on the lift plate,
The lift plate is provided so as to be displaceable from a lowered position to a pushed-down position that is further lowered.
When the cursor moves until it comes into contact with the lift plate displaced to the pressed position, the cursor engages with an engaged portion formed on the lift plate and fixes the lift plate at the pressed position. A paper feed cassette having an engaging portion. An elastic member disposed between the bottom portion of the cassette body and the lower surface of the lift plate and supporting the lift plate displaced to the lowered position;
The sheet feeding cassette according to claim 1, wherein the lift plate is provided so as to be displaceable to a push-down position that further lowers from the lowered position by elastically deforming the elastic member.   3. The sheet feeding cassette according to claim 1, wherein the cursor includes a pair of width direction cursors that align both ends in the width direction orthogonal to the sheet supply direction.   The sheet feeding cassette according to claim 1, wherein the cursor includes a length direction cursor that aligns one end of the sheet in the feeding direction. The length direction cursor is configured to be changeable between a standing posture capable of contacting one end of the sheet feeding direction and a lying posture falling to the lift plate along the bottom of the cassette body. ,
The engaging portion is formed on an upper end surface of the length direction cursor, and engages with the engaged portion of the lift plate when the length direction cursor is changed to the lying posture. The paper feed cassette according to claim 4, wherein   The said engaging part is recessedly provided by the said lift board side of the said cursor so that the edge part of the said lift board as said to-be-engaged part may be fitted. The paper feed cassette described in Crab.   An image forming apparatus comprising the paper feed cassette according to claim 1.

Images