JP6558143B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus including a sheet feeding tray, and more particularly to an image forming apparatus including a large capacity sheet feeding tray capable of accommodating two sheet bundles.

  An electrophotographic image forming apparatus such as a printer, a facsimile machine, a copier, or a combination of these is provided with a plurality of paper feed trays in the vertical direction, and different sizes of paper are stored in each paper feed tray. A configuration is adopted in which the sheet is selectively conveyed to the image forming unit according to the selection or the document size. These paper feed trays are configured such that they can be pulled out from the apparatus main body to the front side, for example, for replenishing paper.

  The paper sizes that can be stored in the paper feed tray include A4 size, A3 size, B5 size, and B4 size. The A4 size and the B5 size are used for general documents, the A3 size has an area twice as large as the A4 size, and the B4 size has an area twice as large as the B5 size, and is used for relatively large tables and drawings. A user who creates a large amount of printed matter of a specific size desires a paper feed tray that can accommodate a large amount of paper of a specific size compared to other sizes of paper.

  Japanese Patent Application Laid-Open No. 2004-133620 proposes a paper tray that can store a large amount of A4 size paper and that stores two paper bundles. In this paper feed tray, when all the sheets of one sheet bundle are supplied to the image forming apparatus main body side, the other sheet bundle is moved to the position where there is no sheet bundle, and the sheet supply is continued. It is possible.

JP 2002-274661 A

  However, the paper feed tray for storing such two paper bundles has the following problems.

  First, the configuration and operation of a paper feed tray for storing two paper bundles will be briefly described (for details, refer to the description of the embodiment of the present invention described later).

  FIG. 9 is a front view showing the structure around the conventional paper feed tray of the image forming apparatus. As shown in the figure, the paper feed tray 100 includes a first stacking unit 101 and a second stacking unit 102, and each can stack a bundle of sheets P1 and P2 made up of a maximum of about 1250 sheets. The sheet bundle P1 placed on the first stacking unit 101 is pushed up by the push-up plate 103 that can be moved up and down so as to come into contact with the sheet feeding unit 104 of the image forming apparatus.

  Therefore, in order to stably supply sheets to the image forming apparatus main body, the sheet bundle P1 placed on the first stacking unit 101 and the sheet bundle P2 placed on the second stacking unit 102 are fixed. It is necessary to provide a gap. When the gap between the sheet bundle P1 and the sheet bundle P2 is buried, the sheet bundle P1 collapses when pushed up, and the sheet bundle P1 is not supplied by the sheet feeding means 104, or a plurality of sheets are conveyed. Trouble may occur.

  However, in the conventional paper feed tray 100, even when the paper stack P1 of the first stacking unit 101 and the paper stack P2 of the second stacking unit 102 are placed with a gap, the paper feed tray 100 is pushed in. The sheet bundles P1 and P2 may come into contact with each other and the above trouble may occur. As a result of investigation by the present inventor, it was found that the contact between the sheet bundles occurs as follows.

  FIG. 10 is a diagram illustrating a process in which a sheet bundle in the first stacking unit and a sheet bundle in the second stacking unit are in contact with each other. FIG. 10A illustrates the rear wall of the sheet feeding tray bent outward. FIG. 6B shows a state after the bending of the rear wall of the paper feed tray is recovered.

  When the sheet bundles P1 and P2 are placed on the first stacking unit 101 and the second stacking unit 102, respectively, and the paper feed tray 100 is pushed into the frame 151 of the apparatus main body, the sheet bundles P1 and P2 are very When the protrusion 107 comes into contact with the frame 151a on the back side in the pushing direction because it is heavy, the rear wall 106 of the paper feed tray 100 bends outward due to the inertia of the paper bundles P1 and P2, as shown in FIG. . When this outward deflection occurs, the sheet bundles P1 and P2 move in the direction of the arrow in the drawing along the rear wall 106 due to inertia, so that they approach the center side of the sheet feeding tray 100 and the gap is buried. Become. Thereafter, as shown in FIG. 10B, the paper feed tray 100 is urged in the pulling direction (Y-axis negative direction) by the repulsive force of the compression coil spring 108, and the notch portion in which the lock lever 109 is provided in the frame 151. 151b is engaged and stabilized at a predetermined position, and the bending of the rear wall 106 is recovered. However, even if the bending of the rear wall 106 is recovered, the gap between the sheet bundle P1 and the sheet bundle P2 remains buried, causing the above trouble.

  The present invention has been made in view of such problems, and an object thereof is to provide an image forming apparatus that includes a paper feed tray that can accommodate a large amount of paper and that can stably feed paper.

  An image forming apparatus according to the present invention that achieves the above object is an image forming apparatus that includes a paper feed tray that accommodates a sheet bundle of a plurality of sheets, and the paper feed tray is arranged in a horizontal direction with respect to the apparatus body. The paper tray can be pulled out and pushed in, and two sheet bundles are placed side by side in the direction perpendicular to the pushing direction with a gap between them, and the wall on the leading end side in the pushing direction of the paper feeding tray A center line that regulates the position of the sheet bundle in the pushing direction and is parallel to the pushing direction of each sheet bundle placing portion of the surface of the paper feed tray on the front side in the pushing direction facing the apparatus main body. A first protrusion is provided in a portion sandwiched between vertical planes passing through the apparatus, and the apparatus main body and the first protrusion come into contact when the paper feed tray is pushed in.

  It is preferable that the first protrusion is provided at a position overlapping the gap between the two sheet bundles when viewed from the pushing direction.

  Further, when the paper feed tray is pushed into the opposite ends of the wall of the paper feed tray at the front end side in the push-in direction facing the device main body in the direction perpendicular to the push-in direction, the paper feed tray comes into contact with the device main body. It is preferable that a second protrusion and a third protrusion are provided.

  More preferably, of the first to third protrusions, the first protrusion first contacts the apparatus main body when the paper feed tray is pushed.

  The first protrusion is preferably provided at a position higher than the center of the paper feed tray in the height direction.

  It is preferable that the positions of the two sheet bundles in a direction perpendicular to the pushing-in direction of the sheet feeding tray are regulated on a surface opposite to the surface where the respective sheet bundles face each other.

  An urging member that urges the paper feed tray in the pull-out direction; and a regulating member that restricts movement of the paper feed tray in the pull-out direction, and the first when the paper feed tray is pushed in It is preferable that the position of the paper feed tray is fixed by the urging member and the regulating member in a state where the first protrusion is separated from the apparatus main body after the protrusion comes into contact with the apparatus main body.

  In the image forming apparatus of the present invention, a large amount of paper can be stored in the paper feed tray, and the paper is not easily collapsed when the paper feed tray is pushed in, so that the paper can be supplied stably. .

FIG. 1 is a schematic diagram showing an embodiment of an image forming apparatus according to the present invention. FIG. 2 is an explanatory diagram of the operation of the paper feeding means of FIG. FIG. 3 is an external perspective view of the lowermost paper feed tray. FIG. 4 is a front view showing a schematic configuration around the lowermost sheet feeding tray of the image forming apparatus shown in FIG. 1, and FIG. 2 shows a state in which a stack of sheets is stored in the stacking unit, FIG. 2B shows a state in which the stack of sheets in the first stacking unit is empty, and FIG. 3C shows a stack of sheets in the second stacking unit. FIG. 4D shows a state in which the sheet bundle moved to the first stacking unit is being fed. FIG. 5 is a plan view showing a schematic configuration around the lowermost sheet feeding tray of the image forming apparatus according to the present invention. FIG. 5A shows a state in which the sheet feeding tray is pushed into the apparatus main body, and FIG. Is a state in which the projection of the paper feed tray is in contact with the apparatus main body, and FIG. 5C shows a state in which the paper feed tray is stable at a predetermined position. 6A and 6B are rear views showing a schematic configuration of the paper feed tray according to the present invention. FIG. 6A shows the center portion in the X-axis direction of the outer surface of the rear wall, and FIG. 6B shows the gap between the sheet bundles. Show. FIG. 7 is a plan view showing a modification of the schematic configuration around the lowermost sheet feed tray of the image forming apparatus shown in FIG. 1, and shows a state in which the projection of the sheet feed tray is in contact with the apparatus main body. FIGS. 8A and 8B are schematic configuration diagrams of the lowermost sheet feeding tray. FIG. 8A is a plan view, and FIG. 8B is a cross-sectional view taken along line aa in FIG. FIG. 9 is a front view showing the structure around the conventional paper feed tray of the image forming apparatus. FIG. 10 is a plan view of the periphery of the paper feed tray for explaining a process in which the paper stack of the first stacking unit and the paper stack of the second stacking unit are in contact with each other. FIG. FIG. 4B shows a state after the bending of the rear wall of the paper feed tray has been recovered.

  Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiment.

  FIG. 1 is a schematic diagram showing an embodiment of an image forming apparatus according to the present invention. An image forming apparatus D shown in FIG. 1 is a full-color image forming apparatus, and includes an image reading unit 1 that reads an original image, an image forming unit 2 that forms an image of the read image on paper, and a paper storage unit 3 that stores paper. Have

  The image reading unit 1 is a unit that conveys and reads a document to an opposite part of the scanner 11 with a slit glass (not shown) sandwiched by an automatic document feeder 13. A manuscript image obtained by irradiation of an exposure lamp installed in the scanner 11 is imaged by an optical system, and is a CCD corresponding to each of three types of wavelength light of red (R), green (G), and blue (B). The image sensor 12 performs AD conversion, converts it into an electrical signal, and generates R, G, and B image data corresponding to the original image.

  The image forming unit 2 forms an image by a well-known electrophotographic method. In the image forming unit 21, the exposure device 22 performs exposure based on image data to form an electrostatic latent image on the surface of the photoreceptor. . Next, toner is attached to the electrostatic latent image to form a toner image. Then, the formed toner image is primarily transferred to the intermediate transfer belt 23. A color toner image is formed by superimposing the respective color toner images on the surface of the intermediate transfer belt 23. Next, the color toner image is secondarily transferred onto the paper P in the transfer unit 24. The toner consumed in the image forming unit 21 is sequentially supplied from the toner bottle 25 for each color.

  The paper storage unit 3 includes paper feed trays 31a, 31b, and 31c (hereinafter sometimes collectively referred to as “paper feed tray 31”) arranged in three stages in the vertical direction (Z-axis direction). FIG. 1 shows a state in which different sizes of paper are stored in the respective paper feed trays 31. As an example of the paper size, the B4 size can be applied to the paper feed tray 31a, the A3 size can be applied to the paper feed tray 31b, and the A4 size can be applied to the paper feed tray 31c. The paper feed trays 31 other than during the paper feeding operation can be pulled out to the front side (the Y-axis negative direction in FIG. 1) with respect to the apparatus main body 50 in order to replenish paper and check the remaining amount. Above the side portions of each paper feed tray 31 on the X axis positive direction side, paper feed means 32a, 32b, and 32c (hereinafter, may be collectively referred to as “paper feed means 32”) are provided.

  FIG. 2 is an explanatory diagram of the operation of the paper feeding means of FIG. As shown in FIG. 2, the paper feed unit 32 includes a pickup roller 321, a paper feed roller 322, and a separation roller 323. The pickup roller 321 sequentially pulls out the uppermost sheet of the sheet bundle P stored in the sheet feed tray 31 and separates the sheets one by one by the sheet feed roller 322 and the separation roller 323 to convey the conveyance path 41 (shown in FIG. 1). ).

  As shown in FIG. 1, the paper drawn from the paper bundle P to the transport path 41 is transported upward by a pair of transport rollers, and the toner image formed by the image forming unit 2 is transferred to the paper by the transfer unit 24. Thereafter, the toner image is melted and fixed on the paper by being heated and pressurized by the fixing roller pair 26. Then, the paper is discharged to the paper discharge tray 27.

  The present invention is not limited to a full-color image forming apparatus, and can be applied to a monochrome image forming apparatus.

  Next, the lowermost paper feed tray will be described. FIG. 3 is an external perspective view of the lowermost paper feed tray 31c. Of the paper feed trays 31 of the image forming apparatus D shown in FIG. 1, the lowermost paper feed tray 31c can accommodate more sheets than the other paper feed trays 31a and 31b. The paper feed tray 31c has a first stacking unit 311 and a second stacking unit 312 for placing a bundle of sheets, respectively, and is arranged in the X-axis direction shown in FIG. A sheet bundle can be accommodated. The first stacking unit 311 is provided with a push-up plate 313 that pushes up a bundle of paper, and the push-up plate 313 is provided with a sensor 314 that detects the presence or absence of paper. The sensor 314 is urged vertically upward, and is pushed into the push-up plate 313 when there is a sheet in the first stacking unit 311 and is pushed up when there is no sheet. In the control unit of the image forming apparatus D, the posture of the sensor 314 is detected electrically or optically to determine the presence or absence of paper. The paper feed tray 31c is provided with a transfer plate 315 for transferring the sheet bundle of the second stacking unit 312 in the direction of the first stacking unit 311. The transfer plate 315 is located at a rest position in contact with the side wall on the second stacking unit 312 side of the paper feed tray 31c except when the sheet bundle is transferred.

  FIG. 4 is a front view showing a schematic configuration around the paper feed tray 31c. FIG. 4 (a) supplies the sheets of the first stacking unit 311 to the apparatus main body and stores the sheet bundle in the second stacking unit 312. (B) is a state where the sheet stack of the first stacking unit is empty, and (c) is a state where the sheet stack of the second stacking unit is transferred to the first stacking unit. (D) shows a state in which the sheet bundle moved to the first stacking unit is being fed.

  As shown in FIG. 4A, a sheet bundle P1 is placed on the first stacking section 311 and a sheet bundle P2 is placed on the second stacking section 312. The positions of the sheet bundles P1 and P2 in the X-axis direction are regulated by the inner surface of the side wall on the X-axis positive direction side of the paper feed tray 31c in the first stacking unit 311, and the second stacking unit 312 is located at the rest position. It is regulated by the inner surface of the plate 315. When the sheet stacking tray 31c is pulled out to replenish the sheet bundle, the sheet stacks P1 and P2 are disposed in contact with these X-axis direction regulating surfaces in the first stacking unit 311 and the second stacking unit 312, thereby A certain gap is provided between the bundles P1 and P2.

  The sheet bundle P1 placed on the first stacking unit 311 is pushed up by the push-up plate 313 so as to be in contact with the pickup roller 321 of the paper feeding unit 32c, and the push-up plate 313 is also raised as the number of sheets decreases.

  When the sensor 314 detects that the sheet bundle P1 has run out, the push-up plate 313 moves to the lowermost position as shown in FIG. Next, as illustrated in FIG. 4C, the sheet bundle P <b> 2 of the second stacking unit 312 is transferred to the first stacking unit 311 by the transfer plate 315.

  Thereafter, as shown in FIG. 4D, the transfer plate 315 returns to the rest position, and the sheet bundle P2 is pushed up by the push-up plate 313 so as to be in contact with the pickup roller 321 of the sheet feeding means 32c.

  5A and 5B are plan views showing a schematic configuration around the paper feed tray 31c. FIG. 5A shows a state in which the paper feed tray is pushed into the apparatus main body, and FIG. 5B shows a projection of the paper feed tray on the apparatus main body. FIG. 2C shows a state in which the paper feed tray is stabilized at a predetermined position.

  As shown in FIG. 5A, the paper feed tray 31c can be pulled out and pushed in the horizontal direction (Y-axis direction in the drawing) into the frame 51 of the apparatus main body, and by pulling out the paper feed tray 31c. The sheet bundles P1 and P2 can be replenished. The positions of the sheet bundles P1 and P2 in the Y-axis positive direction are the wall 316 on the Y-axis positive direction side of the paper feed tray 31c (hereinafter referred to as “rear wall”) in both the first stacking unit 311 and the second stacking unit 312. Regulated by the inner surface of. The sheet bundles P1 and P2 are arranged so as to be in contact with the Y-axis direction regulating surface. Thereby, it is possible to stably feed the sheet to the apparatus main body. The paper feed tray 31c supplied with the paper bundles P1 and P2 is pushed into the frame 51 in the Y-axis positive direction.

  Below the side wall on the X axis positive direction side of the paper feed tray 31c, a lock lever 319 is provided on the bottom surface of the paper feed tray 31c so as to be able to enter and exit in the X axis direction, and attached to the X axis positive direction by a compression coil spring (not shown). It is energized. The lock lever 319 is provided with an inclined surface whose length in the X-axis direction becomes longer in the negative direction of the Y-axis at the portion in contact with the frame 51. When the paper feed tray 31c is pushed into the frame 51, this inclination The surface comes into contact with the frame 51, and the compression coil spring is compressed and pushed into the bottom surface of the paper feed tray 31c.

  Thereafter, as shown in FIG. 5B, when the lock lever 319 is pushed out from the notch 51b of the frame 51, the paper feed tray 31c is urged in the Y-axis negative direction by a compression coil spring 318 described later. The lever 319 engages with the surface of the notch 51b on the Y axis negative direction side. Thus, the lock lever 319 acts as a restricting member that restricts the movement of the paper feed tray 31c in the negative Y-axis direction, and the paper feed tray 31c is stabilized at a predetermined position by the compression coil spring 318 and the lock lever 319. When pulling out the paper feed tray 31c, the lock lever 319 is pulled into the bottom surface of the paper feed tray 31c by pulling the release lever A provided on the front surface of the paper feed tray 31c shown in FIG. can do.

  A surface of the rear wall 316 facing the frame 51a on the back side in the pushing direction (hereinafter referred to as “outer surface”) has a first protrusion 317a at the center in the direction orthogonal to the pushing direction (X-axis direction in the figure), A second protrusion 317b is provided at the end in the negative direction of the X axis, and a third protrusion 317c (hereinafter sometimes referred to as “protrusion 317”) is provided at the end in the positive direction of the X axis. A compression coil spring 318 is provided in the vicinity of the third protrusion 317c.

  FIG. 6 is a rear view of the paper feed tray 31c. With respect to the outer surface of the rear wall 316, the central portion in the X-axis direction is a vertical plane passing through a center line parallel to the Y-axis direction of the first stacking portion 311 as shown in FIGS. 5 (a) and 6 (a). When the first center plane F1 and the vertical plane passing through the center line parallel to the Y-axis direction of the second stacking unit 312 are defined as the second center plane F2, the first center plane F1 and the second center plane F2 of the outer surface of the rear wall 316 The part between.

  When the projection 317 is pushed in the paper feed tray 31c, the first projection 317a comes into contact with the frame 51a before the second projection 317b and the third projection 317c. That is, as shown in FIG. 5A, among the three protrusions 317, the first protrusion 317a protrudes most to the front end side in the pushing direction (Y-axis positive direction side).

  When there is no protrusion at the center of the rear wall as in the conventional paper feed tray described above, when the paper feed tray is pushed in, an outward flexure occurs in the rear wall, and the sheet bundles follow each other along this flexure. Since the paper moves so as to approach, the gap between the sheet bundles may be filled (see FIG. 10).

  However, in the image forming apparatus according to the present embodiment, the paper feed tray 31c pushed into the frame 51 has the first projection at the center before the second projection 317b and the third projection 317c at both ends in the X-axis direction. The protrusion 317a contacts the frame 51a. Therefore, when the paper feed tray 31c is pushed in, as shown in FIG. 5B, the rear wall 316 is bent inward, and the paper bundle P1 and the paper bundle P2 are separated from each other (arrows in the figure). Direction) force. Therefore, the gap between the sheet bundle P1 and the sheet bundle P2 is less likely to be filled as compared with the case where there is no protrusion at the center. Therefore, the sheet bundle P1 of the first stacking unit 311 can be pushed up stably, and paper can be stably fed from the paper feed tray 31c.

  As described above, the first protrusion 317a is disposed at the center portion in the X-axis direction of the outer surface of the rear wall 316, that is, at the portion sandwiched between the first center surface F1 and the second center surface F2 of the outer surface of the rear wall 316. Just do it. As shown in FIG. 6B, the gap Q between the two sheet bundles P1 and P2 as viewed from the Y-axis direction (including a portion extending in the Z-axis direction between the sheet bundles P1 and P2) is included. ). By disposing at such a position, any of the sheet bundles P1 and P2 placed on either the first stacking unit 311 or the second stacking unit 312 is placed on the rear wall 316 when the sheet feeding tray is pushed in. It is possible to prevent outward deflection from occurring substantially evenly and approach each other.

  The width of the first protrusion 317a in the X-axis direction is such that the gap Q between the sheet bundle P1 and the sheet bundle P2 is as long as the first protrusion 317a does not contact any of the second protrusion 317b and the third protrusion 317c. It may be wider or narrower than the width or the same. In any case, it is preferable that the first protrusion 317a partially overlaps the gap Q between the sheet bundle P1 and the sheet bundle P2 when viewed from the Y-axis direction, and more preferably the whole overlaps. FIG. 6B shows a case where the width of the first protrusion 317a in the X-axis direction is the same as the width of the gap between the sheet bundle P1 and the sheet bundle P2.

  In the image forming apparatus of the present invention, as long as the first protrusion 317a is provided, the second protrusion 317b and the third protrusion 317c may be omitted. However, when only the first protrusion 317a is provided, the impact at the time of contact with the apparatus main body can be dispersed and the durability of the paper feed tray 31c is improved when the protrusions are also provided at both ends. be able to.

  FIG. 7 is a plan view showing a modified example of the schematic configuration around the paper feed tray 31c, and shows a state where the protrusions of the paper feed tray are in contact with the apparatus main body. When the first to third protrusions 317 are provided, the first protrusion 317a may not contact the frame 51a first when the paper feed tray 31c is pushed. By providing the first protrusion 317a on the outer surface of the rear wall 316, the outward deflection generated on the rear wall 316 is suppressed as compared with the conventional case where there is no protrusion at the center, and the sheet bundles P1, P2 are suppressed. Movement is also suppressed. Accordingly, the gap between the sheet bundle P1 and the sheet bundle P2 is not easily filled, and the sheet can be stably fed from the sheet feeding tray 31c. FIG. 7 shows a case where the positions of the three protrusions 317 on the front end side (Y-axis positive direction side) in the pushing direction are the same.

  8A and 8B are schematic configuration diagrams of the paper feed tray 31c. FIG. 8A is a plan view, and FIG. 8B is a cross-sectional view taken along the line aa of FIG. As shown in FIG. 8B, in the cross section of the portion where the first protrusion 317a is provided, the rear wall 316 of the paper feed tray 31c is cantilevered with the bottom surface as a fulcrum and the first protrusion 317a as the action point. It is like a beam. Therefore, the higher the position of the first protrusion 317a on the rear wall 316, the longer the distance between the fulcrum and the action point, and the second protrusion 317b and the third protrusion 317c are ahead when the paper feed tray 31c is pushed. When the first protrusion 317a contacts the frame, the rear wall 316 is likely to bend inwardly. Further, even when the first protrusion 317a does not contact the frame first, the outward deflection of the rear wall 316 caused by the inertia of the sheet bundle when the first protrusion 317a contacts the frame of the apparatus main body. Can be suppressed. Further, in order to obtain the effect of such bending of the rear wall 316, the first protrusion 317a is preferably provided at a position higher than the center C in the height direction of the paper feed tray 31c.

  As described with reference to FIG. 5C, the position of the paper feed tray 31c pushed into the apparatus main body is such that the compression coil spring 318 that biases the paper feed tray 31c in the negative Y-axis direction and the paper feed tray 31c. It is determined that the first protrusion 317a is separated from the frame 51a by the lock lever 319 that restricts movement in the negative Y-axis direction and the cutout portion 51b of the frame 51 that engages with the lock lever 319. preferable.

  When the position of the paper feed tray 31c is determined in a state where the first protrusion 317a is in contact with the frame 51a, the first protrusion 317a of the three protrusions 317 projects most in the Y-axis positive direction side, This is because when the second protrusion 317b and the third protrusion 317c are not provided and only the first protrusion 317a is provided, the rear wall 316 of the paper feed tray 31c is always bent inward. In this case, the sheet bundles P1 and P2 and the rear wall 316 are partially rubbed when the sheet bundle P1 is pushed up or the sheet bundle P2 is transferred from the second stacking unit 312 to the first stacking unit 311. P1 and P2 may collapse.

  Further, even if the first protrusion 317a is separated from the frame 51a, the rear wall 316 may be bent by the repulsive force of the compression coil spring 318 provided on the rear wall 316. In order to suppress the occurrence of such bending, the repulsive force of the compression coil spring 318 is preferably set to a minimum strength that presses the paper feed tray 31c in the pulling direction. The relationship between the rear wall 316 and the compression coil spring 318 is such that the rear wall 316 of the paper feed tray 31c is a beam having the bottom surface or both side surfaces in the X-axis direction as fulcrums and the compression coil spring 318 as an action point. Therefore, it is also preferable to arrange the compression coil spring 318 on the bottom surface of the paper feed tray 31c or the end portion in the X-axis direction so as to shorten the distance between the fulcrum and the action point.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this content. The embodiments of the present invention can be variously modified without departing from the spirit of the invention.

  The image forming apparatus of the present invention is useful because it can stably supply paper even when a paper feed tray capable of storing a large amount of paper is used.

D Image forming apparatus 31a, b, c Feed tray C Center of feed tray height 317a First projection 317b Second projection 317c Third projection 318 Compression coil spring 319 Lock lever P1, P2 Sheet bundle F1, F2 Vertical plane that passes through the center line parallel to the paper tray push-in direction of the paper bundle

Claims (7)

An image forming apparatus including a paper feed tray for storing a bundle of paper sheets composed of a plurality of sheets,
The paper feed tray can be pulled out and pushed horizontally with respect to the apparatus body,
Wherein the paper feed tray, two sheet bundle mounting portion in a direction perpendicular to the pressing direction is found provided side by side with a gap,
The position of the sheet bundle in the pushing direction is regulated by the wall surface on the leading end side in the pushing direction of the sheet feeding tray,
A portion of the wall of the paper feed tray on the front end side in the pushing direction facing the apparatus main body and sandwiched between vertical surfaces passing through a center line parallel to the pushing direction of each of the two sheet bundle mounting portions. A first protrusion is provided;
The image forming apparatus, wherein the apparatus main body and the first protrusion come into contact with each other when the paper feed tray is pushed in. Said first projection, wherein when viewed from the push-in direction, the image forming apparatus according to claim 1, characterized in that provided at a position overlapping the gaps of the two sheet bundle placement section.   A second surface that comes into contact with the apparatus main body when the paper feed tray is pushed into both ends of the wall of the paper feed tray on the front side in the pushing direction facing the apparatus main body in a direction perpendicular to the pushing direction. The image forming apparatus according to claim 1, wherein a protrusion and a third protrusion are provided.   4. The image forming apparatus according to claim 3, wherein when the sheet feeding tray is pushed in, the first protrusion of the first to third protrusions first contacts the apparatus main body. 5.   The image forming apparatus according to claim 1, wherein the first protrusion is provided at a position higher than a center of the paper feed tray in a height direction.   6. The position of two paper bundles in a direction perpendicular to the pushing direction of the paper feed tray is regulated on a surface opposite to the surface where the paper bundles face each other. The image forming apparatus according to claim 1. An urging member that urges the paper feed tray in the pull-out direction; and a regulating member that restricts movement of the paper feed tray in the pull-out direction;
After the first protrusion comes into contact with the apparatus main body when the paper feed tray is pushed in, the paper supply tray is separated from the apparatus main body by the biasing member and the regulating member. The image forming apparatus according to claim 1 , wherein the position is fixed.

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