Paper feed cassette and image forming apparatus

Abstract

To provide a paper feed cassette capable of stably supporting sheets regardless of a size of the sheets.SOLUTION: A paper feed cassette 15 of the present invention includes a main body portion 21 that stores sheets fed along a predetermined feeding direction, a lift plate 23 that is provided in the main body portion 21 so as to be able to move up and down and on which the sheets are placed, and a pair of a side cursors 25 that slide in a width direction orthogonal to the feeding direction and come in contact with side edges of the sheet placed on the lift plate 23 to position the sheet. A notch 37 through which the pair of side cursors 25 pass is formed in a portion of the lift plate 23 on a downstream side in the feeding direction, and a lift auxiliary plate 27 on which the sheet can be placed together with the lift plate 23 can be attached to and detached from the notch 37.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a paper feed cassette that accommodates sheets on which an image is to be formed, and an image forming apparatus. [Background technology]

[0002] In an image forming apparatus such as a multifunction machine or a printer, a sheet is fed from a paper feed cassette to an image forming section along a predetermined feeding direction. The paper feed cassette includes a lift plate on which the sheet is placed that can be raised and lowered, and a pair of side cursors that position the placed sheet in the width direction of the sheet that is perpendicular to the feeding direction.

[0003] The pair of side cursors slide in the width direction to position the sheet. For this reason, as described in, for example, Patent Document 1, the lift plate is formed with a notch through which the pair of side cursors pass. In some cases, the notch is formed in multiple places. In other words, the lift plate may be formed in a beam shape. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-7105 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the paper feed cassette described in the above-mentioned Patent Document 1, a pair of side cursors are arranged on the downstream side in the feeding direction (the side closer to the paper feeder) so that small-sized sheets can be positioned. In other words, the notch is also formed on the downstream side in the feeding direction. If a notch is formed in this way, there are cases where the sheet cannot be stably placed on the lift plate.

[0006] For example, when a large number of large-sized sheets (e.g., 4,000 sheets) are loaded, the downstream portion in the feeding direction overlaps with the notch. Then, the downstream portion is not supported by the lift plate and may bend, which may cause the sheets to be unable to be fed stably. To address this, the side cursor may be provided with a notch to allow the beam-shaped lift plate to pass through. However, when a large number of sheets are loaded, the dimensions of the notch become large, making it difficult to ensure the strength of the side cursor.

[0007] SUMMARY OF THE PRESENT DISCLOSURE In consideration of the above circumstances, an object of the present invention is to provide a sheet feed cassette capable of stably supporting sheets regardless of the size of the sheets, and an image forming apparatus equipped with the sheet feed cassette. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the paper feed cassette of the present invention is characterized in that it comprises a main body portion in which sheets to be fed along a predetermined feeding direction are stored, a lift plate that is movable within the main body portion and has a sheet loading surface on which the sheets are placed, a pair of side cursors that slide in a width direction perpendicular to the feeding direction and abut against the side edges of the sheets placed on the lift plate to position the sheets, and a lift auxiliary plate that is attached to cutout portions formed in the lift plate that allow the pair of side cursors to move, and on which the sheets can be placed together with the lift plate.

[0009] In the sheet feed cassette of the present invention, an upper surface of the lift auxiliary plate may be lower than the sheet placement surface of the lift plate.

[0010] In the paper feed cassette of the present invention, the lift auxiliary plate may be composed of a plurality of lift auxiliary pieces that can be connected to each other, and the width of the lift auxiliary plate may be changed by changing the number of the lift auxiliary pieces that are connected.

[0011] In the paper feed cassette of the present invention, the pair of side cursors may have a housing portion capable of housing the lift auxiliary plate detached from the lift plate.

[0012] The paper feed cassette of the present invention may be characterized in that it comprises the paper feed cassette, an apparatus main body to which the paper feed cassette is removably attached, a paper feed device that feeds sheets from the paper feed cassette attached to the apparatus main body, and an image forming unit that forms an image on the sheet fed from the paper feed cassette by the paper feed device. Effect of the Invention

[0013] According to the present invention, by attaching the lift auxiliary plate to the cutout of the lift plate, a large-sized sheet can be lifted and lowered without being bent. [Brief description of the drawings]

[0014] [Figure 1] 1 is a front view showing a schematic internal structure of an image forming apparatus and a large-capacity deck according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view showing a schematic diagram of a large-capacity deck according to an embodiment of the present invention; [Diagram 3] FIG. 2 is a plan view showing the large-capacity deck (with the lift auxiliary plate removed) according to one embodiment of the present invention. [Figure 4] FIG. 2 is a plan view showing a large-capacity deck (with a lift auxiliary plate attached) according to one embodiment of the present invention. [Diagram 5] FIG. 5 is a cross-sectional view taken along line III-III of FIG. [Figure 6] FIG. 11 is a perspective view showing a connecting hole portion of a lift plate in the large-capacity deck according to one embodiment of the present invention. [Figure 7] 1 is a perspective view showing a stopper mechanism of a side cursor and a lift auxiliary plate supported by the side cursor in a large-capacity deck according to one embodiment of the present invention. FIG. [Figure 8A] 1 is a plan view showing a lift auxiliary plate in a large-capacity deck according to an embodiment of the present invention. FIG. [Figure 8B] 1 is a perspective view showing a connecting hole portion and a connecting hook portion of a lift auxiliary plate in a large-capacity deck according to one embodiment of the present invention. FIG. [Figure 9] 11 is a perspective view showing a process of attaching a lift auxiliary plate to a lift plate in a large-capacity deck according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus and a large capacity deck according to an embodiment of the present invention will now be described with reference to the drawings.

[0016] First, the overall configuration of the image forming apparatus will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing an outline of the image forming apparatus. In the following description, the front side of the paper in Fig. 1 is the front side (front side) of the image forming apparatus. Fr, Rr, L, and R in each figure respectively indicate the front side, rear side, left side, and right side of the image forming apparatus 1.

[0017] The device body 3 of the image forming apparatus 1 is provided with a paper feed section 5, an electrophotographic image forming section 7, and a discharge tray 9. Furthermore, the device body 3 is formed with a transport path 11 along which a sheet is transported vertically from the paper feed section 5 through the image forming section 7 to the discharge tray 9.

[0018] A large-capacity deck 15 is connected to the image forming apparatus 1. The large-capacity deck 15 can accommodate a large amount of sheets (e.g., 4000 sheets). When the large-capacity deck 15 is connected to the image forming apparatus 1, it becomes possible to feed sheets to the conveying path 11 of the image forming apparatus 1. The large-capacity deck 15 is an example of a paper feed cassette of the present invention.

[0019] Next, the large-capacity deck 15 will be described with reference to Fig. 2 to Fig. 6. Fig. 2 is a perspective view showing the main body of the large-capacity deck, Fig. 3 and Fig. 4 are plan views showing the main body of the large-capacity deck, Fig. 3 shows the state without the lift auxiliary plate attached, and Fig. 4 shows the state with the lift auxiliary plate attached. Fig. 5 is a cross-sectional view taken along III-III in Fig. 4. Fig. 6 is a perspective view showing the connection hole of the lift plate.

[0020] As shown in FIG. 2, FIG. 3, and FIG. 4, the large-capacity deck 15 includes a main body 21 in which sheets are stored, a lift plate 23 provided on the main body 21 on which the sheets are placed, a pair of side cursors 25 (25F, 25R) provided on the main body 21 for positioning the sheets placed on the lift plate 23, and a lift auxiliary plate 26 (see FIG. 3) that is detachable from the lift plate 23. In this embodiment, the sheets are fed along a feeding direction X from right to left in FIG. 3 and FIG. 4. In the following description, the upstream side and the downstream side refer to the upstream side and the downstream side in the feeding direction X. Also, the direction (front-rear direction) intersecting with the feeding direction X is the width direction Y. Furthermore, the large-capacity deck 15 includes a connecting portion connected to the image forming apparatus 1, and a sheet feeding device that feeds the sheets placed on the lift plate 23 and conveys them to the image forming apparatus 1 (both are not shown).

[0021] The main body 21 has a dimension capable of loading a large amount (e.g., 4,000 sheets) of sheets of the maximum size (e.g., A3 size) on which images can be formed by the image forming unit 7 of the image forming apparatus 1. Slits 21a are formed in both side plates of the main body 21 at the upstream and downstream ends, along the up-down direction.

[0022] 3, a plurality of guide rails 31 are supported along the width direction Y on the downstream portion of the bottom plate of the main body 21. The guide rails 31 are arranged on the upstream and downstream sides on one side and the other side of the center in the width direction Y. Furthermore, a stopper rod 33 is supported along the width direction Y between the upstream and downstream guide rails 31 on one side (the front side in this example) of the center in the width direction Y.

[0023] The lift plate 23 is a plate-shaped member having dimensions large enough to accommodate a maximum-sized sheet, and is formed of a placement portion 23X on which the sheet is placed, and a peripheral portion 23Y bent downward at a substantially right angle from the periphery of the placement portion 23X, as shown in Fig. 5 and Fig. 6. The upper surface of the placement portion 23X is the sheet placement surface.

[0024] As shown in Fig. 3 and Fig. 4, the lift plate 23 has an upstream portion 23a on the upstream side, a downstream portion 23b on the downstream side, and a central portion 23c between the upstream portion 23a and the downstream portion 23b. The upstream portion 23a and the downstream portion 23b have a rectangular planar shape that is long in the width direction Y and short in the feeding direction X. The upstream portion 23a and the downstream portion 23b have the same width, and the length of the downstream portion 23b is shorter than the length of the upstream portion 23a. The central portion 23c is formed in the center of the width direction Y along the feeding direction X. The central portion 23c has a width shorter than the upstream portion 23a and the downstream portion 23b, and is narrower than the width of a minimum size sheet (e.g., a postcard).

[0025] With this configuration, rectangular cutout portions 37 are formed on both sides in the front-rear direction of the central portion 23c of the lift plate 23. As shown in Fig. 3, the guide rails 31 and the stopper rod 33 of the main body portion 21 are exposed through the cutout portions 37. In addition, a rectangular opening 39 is formed along the feeding direction X at the center of the width direction Y in the central portion 23c and the upstream side portion 23a.

[0026] As shown in Fig. 3, a plurality of connecting recesses 41 (41a, 41b) are formed along the periphery of each cutout portion 37. As shown in Fig. 6, the connecting recess 41 has a rectangular recess 43 recessed from the placement portion 23X (sheet placement surface), a rectangular opening 45 formed in the recess 43 at the corner between the placement portion 23X and the periphery 23Y, and a protrusion 47 protruding upward from the lower edge of the opening 45. The depth of the recess 43 is smaller than the plate thickness of the lift plate 23. In addition, the upper surface of the protrusion 47 is flat and is formed lower than the bottom surface of the recess 43.

[0027] 3, the connecting recesses 41 are arranged at a predetermined interval on the upstream and downstream edges of the cutout portion 37 and on the side edges of the cutout portion 37. Of the connecting recesses 41 on each edge, the depth of the recess 43 of the connecting recess 41a arranged on the outer side in the width direction Y is deeper than the recess 43 of the connecting recess 41b arranged on the inner side.

[0028] As shown in FIG. 3 and FIG. 4, the lift plate 23 has four corners provided with pins 51 along the width direction Y. As shown in FIG. 2, each pin 51 protrudes outward through a slit 21a formed in the side plate of the main body 21. A wire 52 is connected to each pin 51. Each wire 52 is connected to a winding roller 54 via a pulley 53 or the like. By rotating the winding roller 54 in one direction, each wire 52 is wound around the winding roller 54, and the lift plate 23 rises while remaining in a horizontal position. The lift plate 23 rises to a paper feed position where the top sheet of the loaded sheets can be fed by a paper feeder (not shown). On the other hand, by rotating the winding roller 54 in the other direction, each wire 52 is unwound from the winding roller 54, and the lift plate 23 descends while remaining in a horizontal position. The lift plate 23 descends until it reaches the bottom plate of the main body 21.

[0029] Next, the pair of side cursors 25 (25F, 25R) will be described with reference to Fig. 7 in addition to Fig. 3 and Fig. 4. Fig. 7 is a perspective view showing a stopper mechanism of the side cursors, etc.

[0030] As shown in Figures 3 and 4, the pair of side cursors 25 include a front cursor 25F and a rear cursor 25R, each of which has a side wall portion 55 that stands upright relative to the bottom plate of the main body portion 21 and an engagement portion 57 along the bottom plate of the main body portion 21.

[0031] 7, the side wall portion 55 is formed of a vertical wall 55a having a predetermined length and a predetermined height, and an upper wall 55b and a lower wall 55c bent outward from the upper and lower edges of the vertical wall 55a in the width direction Y. The length of the side wall portion 55 in the feeding direction X is slightly shorter than the length of the cutout portion 37 of the lift plate 23 (see FIGS. 3 and 4), and the height is higher than the height of the maximum capacity of sheets.

[0032] The engagement portion 57 extends in the width direction Y from the upstream end of the lower edge of the side wall portion 55 toward the center in the width direction Y. As shown in Fig. 3, the engagement portion 57 of the front side cursor 25F has a rack gear formed along the downstream edge, and the engagement portion 57 of the rear side cursor 25R has a rack gear formed along the upstream edge.

[0033] The front and rear side cursors 25F, 25R are disposed in the cutout portion 37 of the lift plate 23 so that the respective side wall portions 55 face each other in the width direction Y. Each engagement portion 57 is slidably supported by the guide rail 31 of the main body portion 21. The rack gear of each engagement portion 57 meshes with a pinion gear (not shown) supported by the bottom plate of the main body portion 21. In addition, the stopper rod 33 of the main body portion 21 penetrates the lower end portion of the side wall portion 55 of the front side cursor 25F.

[0034] When the side wall portion 55 of the front side cursor 25F is slid in one direction, the engaging portion 57 slides along the guide rail 31 together with the side wall portion 55, the pinion gear rotates, and the engaging portion 57 of the rear side cursor 25R slides along the guide rail 31 in the other direction. Since each engaging portion 57 is provided with a bearing (not shown), each engaging portion 57 slides smoothly. As a result, the side wall portions 55 slide synchronously in the direction approaching or separating from each other. At this time, the side wall portions 55 pass through both notches 37 of the lift plate 23. The side wall portions 55 slide in the direction approaching each other, and the vertical walls 55a abut against the side edges of the sheet placed on the lift plate 23, so that the sheet is positioned with respect to the center in the width direction Y. In this way, the inner surface of the vertical wall 55a is a regulating surface that regulates the position of the sheet.

[0035] The pair of side cursors 25 are provided with a stopper mechanism that is fixed at a predetermined position so as not to slide. As shown in FIG. 7, the stopper mechanism is composed of an operating arm 61 and an engaging arm 62 that are provided to be interlocked with each other, and is disposed outside the vertical wall 55a of the side wall portion 55 of the front cursor 25F. The length of the operating arm 61 is longer than the length of the engaging arm 62. The central portion of the operating arm 61 is rotatably supported by a support shaft 63 along the feeding direction X. As a result, the operating arm 61 rotates around the support shaft 63. A handle 65 that is operated by a user is formed at the upper end of the operating arm 61. The handle 65 is exposed from an opening formed in the upper wall 55b of the side wall portion 55. The operating arm 61 is urged by a urging member (not shown) so that the portion above the support shaft 63 rotates outward and the portion below the support shaft 63 rotates inward.

[0036] The engagement arm 62 is disposed below the operation arm 61. The center of the engagement arm 62 is rotatably supported by a support shaft 64 along the feeding direction X. As a result, the engagement arm 62 rotates around the support shaft 64. The upper end of the engagement arm 62 overlaps the lower end of the operation arm 61 from the outside. An opening 67 along the width direction Y is formed at the lower end of the engagement arm 62. The stopper rod 33 penetrating the side wall portion 55 is inserted into this opening 67. In addition, the engagement arm 62 is biased by a biasing member (not shown) in a direction in which a portion above the support shaft 64 rotates inward and a portion below the support shaft 64 rotates outward. As a result, the periphery of the opening 67 engages with the stopper rod 33, and the engagement arm 62 becomes immovable relative to the stopper rod 33 due to friction between them. That is, the front side cursor 25F becomes immovable, and the sliding of the pair of side cursors 25 is restricted.

[0037] When the handle 65 of the operating arm 61 is pulled inward to rotate the operating arm 61 around the support shaft 63, the upper end of the engagement arm 62 is pushed outward by the lower end of the operating arm 61, and the engagement arm 62 rotates around the support shaft 64. As a result, the periphery of the opening 67 moves away from the stopper rod 33. That is, the engagement between the engagement arm 62 and the stopper rod 33 is released. This allows the front side cursor 25F to move, allowing the pair of side cursors 25 to slide. In this way, when the handle 65 of the operating arm 1 is pulled inward to slide the side cursor 25 to a predetermined position and then the handle 65 is released, the periphery of the opening 67 of the engagement arm 62 engages with the stopper rod 33, and the side cursor 25 becomes immovable and is fixed in a predetermined position.

[0038] Next, the lift auxiliary plate 26 will be described with reference to Fig. 4, Fig. 8A and Fig. 8B. Fig. 8A is a plan view showing the lift auxiliary plate, and Fig. 8B is a perspective view showing the connection hole portion and the connection hook portion of the lift auxiliary plate.

[0039] 4, the lift auxiliary plate 26 includes two lift auxiliary pieces 27 attached to the lift plate 23 at one cutout portion 37, and two lift auxiliary pieces 27 attached to the lift plate 23 at the other cutout portion 37. The lift auxiliary pieces 27 have the same shape.

[0040] 8A and 8B, each lift auxiliary piece 27 is a rectangular plate piece having a length equal to that of the cutout portion 37, a width shorter than that of the cutout portion 37, and a plate thickness equal to that of the lift plate 23. As shown in Fig. 8B, each lift auxiliary piece 27 is formed of a placement portion 27X on which a sheet is placed, and a peripheral portion 27Y bent downward at a substantially right angle from the peripheral edge of the placement portion 27X. The upper surface of the placement portion 27X is the sheet placement surface.

[0041] A plurality of connecting hook portions 71 and a plurality of connecting recesses 41 are formed on the periphery of each lift auxiliary piece 27. As shown in Fig. 8A, the connecting hook portions 71 are formed on one side edge at a predetermined interval, and are further formed on the end portions of both end edges opposite the one side edge. The connecting recesses 41 are formed on the other side edge at a predetermined interval.

[0042] 8B, the connecting hook portion 71 has an extension portion 73 extending outward from the mounting portion 27X, and a bent portion 75 bent downward at a substantially right angle from the tip of the extension portion 73. A notch 77 is formed on each side of the extension portion 73.

[0043] The connecting recess 41 has the same structure as the connecting recess 41 (see FIG. 6) of the lift plate 23, and has a rectangular recess 43 recessed from the mounting portion 27X, a rectangular opening 45 formed in the recess 43 at the corner between the mounting portion 27X and the peripheral portion 27Y, and a protruding piece 47 protruding upward from the lower edge of the opening 45. The upper surface of the protruding piece 47 is flat and is formed lower than the bottom surface of the recess 43.

[0044] 3 and 4 again, the main body 21 is provided with an end cursor 81. The end cursor 81 is disposed at the center of the bottom plate of the main body 21 in the width direction Y. The end cursor 81 is supported slidably along the feeding direction X through the opening 39 of the lift plate 23.

[0045] The procedure for placing sheets on the large-capacity deck having the above configuration will be described with reference to Figs. 3 to 5 and Fig. 9. Fig. 9 is a perspective view showing the process of attaching the lift auxiliary plate to the lift plate. In the initial state (a state in which no sheets are placed), the pair of side cursors 25 are slid to the outermost positions (see Fig. 3).

[0046] When a sheet of the minimum size (e.g., a postcard) is placed on the lift plate 23, the lift auxiliary plate 27 is not attached to the lift plate 23 as shown in FIG. 3. The sheet is mainly placed on the downstream side portion 23b and the center portion 23c of the lift plate 23. After the sheet is placed, the stopper mechanism of the pair of side cursors 25 is released (see FIG. 7, the handle 65 of the operation arm 61 is pulled inward), and one of the side cursors 25 is slid to abut the vertical wall 55a (see FIG. 7) of the side wall portion 55 of the pair of side cursors 25 against the side edge of the sheet. This positions the sheet at the center in the width direction Y. Furthermore, the end cursor 81 is slid to abut against the end edge of the sheet. After that, the lift plate 23 is raised until the top sheet of the placed sheets reaches the paper feed position.

[0047] When a sheet of the maximum size (e.g., A3 size) is placed on the lift plate 23, the sheet is placed on the upstream side portion 23a, the central portion 23c, and the downstream side portion 23b of the lift plate 23, and the downstream portion of the sheet overlaps the cutout portion 37. When the sheet placed in this manner overlaps the cutout portion 37, there is a risk that the sheet may bend as described above. In particular, in the case of a large amount of sheets, the possibility of bending increases. Therefore, in such a case, the lift auxiliary plate 26 is attached to the lift plate 23. In this example, a case where two lift auxiliary pieces 27 are attached to each of the cutout portions 37 of the lift plate 23 will be described.

[0048] First, the connecting hook portion 71 of the first lift auxiliary piece 27 is connected to the connecting recess 41 of the lift plate 23. In detail, the connecting hook portion 71 of the first lift auxiliary piece 27 is engaged with the two connecting recesses 41 on the side edges of the lift plate 23 and the connecting recess 41b on the inside of the end edge. At this time, as shown in FIG. 9, the bent portion 75 of the connecting hook portion 71 is inserted into the opening 45 of the connecting recess 41b. As a result, the extension portion 73 of the connecting hook portion 71 is placed on the upper surface of the protruding piece 47 of the connecting recess 41b. Since the upper surface of the protruding piece 47 is located lower than the lower surface of the recess 43, as shown in FIG. 5, the sheet placing surface of the placing portion 27X of the first lift auxiliary piece 27 is lower than the sheet placing surface of the placing portion 23X of the lift plate 23.

[0049] Next, the connecting hook portion 71 of the second lift auxiliary piece 27 is connected to the connecting recess 41 of the lift plate 23 and the connecting recess 41 of the first lift auxiliary piece 27. In detail, the connecting hook portion 71 of the side edge of the second lift auxiliary piece 27 is connected to the connecting hole portion 41 of the first lift auxiliary piece 27, and the connecting hook portion 71 of the end edge is connected to the outer connecting recess 41a of the end edge of the lift plate 23. As described above, the sheet placing surface of the placing portion 27X of the first lift auxiliary piece 27 is lower in height than the sheet placing surface of the placing portion 23X of the lift plate 23. Furthermore, the depth of the recess 43 of the outer connecting recess 41a is deeper than the recess 43 of the inner connecting recess 41b. Therefore, as shown in FIG. 5, the sheet placement surface of the placement portion 27X of the second lift assist piece 27 is lower than the sheet placement surface of the placement portion 27X of the first lift assist piece 27.

[0050] After the two lift auxiliary pieces 27 are attached to the respective cutouts 37 in this manner, a sheet is placed on the lift plate 23. The downstream portion of the sheet is supported by the lift plate 23 and the lift auxiliary plate 26, so that the sheet can be placed without bending. After the sheet is placed, the stopper mechanism of the pair of side cursors 25 is released as described above, and one of the side cursors 25 is slid to bring the vertical wall 55a of the side wall portion 55 of the pair of side cursors 25 into contact with the side edge of the sheet. This positions the sheet at the center in the width direction Y. Furthermore, the end cursor 81 is slid to bring it into contact with the end edge of the sheet. Thereafter, the lift plate 23 is raised until the top sheet of the placed sheets reaches the sheet feeding position.

[0051] As described above, according to the present invention, by attaching the lift auxiliary plate 26 to the cutout portion 37 of the lift plate 23, it is possible to raise and lower large-sized sheets without bending. Therefore, it is possible to stably feed the sheets. In addition, the lift auxiliary plate 26 can be attached to and detached from the lift plate 23 by a simple operation using the connecting hook portion 71 and the connecting recess portion 41.

[0052] In addition, since the height of the sheet placement surface of the lift auxiliary plate 26 is lower than the height of the sheet placement surface of the lift plate 23, the side edge of the sheet can be prevented from getting caught in the gap between the lift plate 23 and the lift auxiliary plate 26 or in the gap between the lift auxiliary plates 26.

[0053] In addition, since the multiple lift auxiliary pieces 27 have the same shape, the number of lift auxiliary pieces 27 attached to the cutout portions 37 can be changed according to the size of the sheet. For example, in the case of a relatively small sized sheet, one lift auxiliary piece 27 may be attached to each cutout portion 37. Furthermore, the number of lift auxiliary pieces 27 that can be attached to each cutout portion 37 is not limited to two, and may be three or more. Furthermore, the widths of the multiple lift auxiliary pieces 27 may be different. In this case, the connecting recess 41 of the lift plate 23 is arranged to match the position of the connecting hook portion 71 of the lift auxiliary piece 27.

[0054] Next, a modified example of the present invention will be described with reference to Fig. 7. In this modified example, a support plate 91 capable of accommodating the lift auxiliary piece 27 is provided on one side cursor 25F.

[0055] The support plate 91 is provided between the upper and lower walls 55b, 55c on the outer surface of the vertical wall 55a of the side wall portion 55 of one side cursor 25F. An opening 92 having a size capable of accommodating the lift auxiliary piece 27 is formed in the support plate 91. Hook pieces 93 are formed at a predetermined interval on one vertical edge of the opening 92. Projections 95 are formed at a predetermined interval on the other vertical edge of the opening 92. The support plate 91 is an example of an accommodating portion for the lift auxiliary plate 26 of the present invention.

[0056] The lift auxiliary plate 27 can be supported on the support plate 91 by engaging the extension portion 73 and the bent portion 75 of each connecting hook portion 71 of the lift auxiliary plate 27 with the hook piece 93 and engaging the protrusion piece 95 with the opening 45 of each connecting recess 41.

[0057] This eliminates the need to provide a new storage space for the lift auxiliary pieces 27, making it easier to manage the lift auxiliary plates 26.

[0058] Although the present invention has been described with reference to specific embodiments, the present invention is not limited to the above embodiments, and those skilled in the art may modify the above embodiments without departing from the scope and spirit of the present invention. [Explanation of symbols]

[0059] 1. Image forming device 7 Image forming section 15 Large capacity deck (paper feed cassette) 21 Main body 23 Lift Board 25 Side Cursor 26 Lift support plate 27 Lifting aid 37 Cutout 91 Support plate (accommodating section)

Claims

1. a main body portion for accommodating sheets to be fed in a predetermined feeding direction; a lift plate provided in the main body portion so as to be capable of rising and lowering and having a sheet placement surface on which the sheet is placed; a pair of side cursors that slide in a width direction perpendicular to the feeding direction and abut against side edges of the sheet placed on the lift plate to position the sheet; a lift auxiliary plate that is attached to a cutout portion formed in the lift plate and that allows the pair of side cursors to move, and that can place the sheet together with the lift plate; 13. A sheet feed cassette, comprising: a lift plate having a top surface that is lower than a sheet placement surface of the lift plate;

2. The paper feed cassette according to claim 1, wherein the lift auxiliary plate is composed of a plurality of lift auxiliary pieces that can be connected to each other, and the width of the lift auxiliary plate can be changed by changing the number of the lift auxiliary pieces that are connected.

3. 3. The sheet feed cassette according to claim 1, wherein the pair of side cursors have a storage portion capable of storing the lift auxiliary plate detached from the lift plate.

4. A paper feed cassette according to any one of claims 1 to 3; an apparatus main body to which the paper feed cassette is detachably attached; a sheet feeding device that feeds a sheet from the sheet feeding cassette that is attached to the device body; an image forming section that forms an image on the sheet fed from the paper feed cassette by the paper feed device.

Images