JP4784048B2 - Paper tray - Google Patents

Description

  The present invention relates to a paper tray on which paper is stacked in such an image forming apparatus, which is attached to an image forming apparatus such as a printer, a facsimile machine, a copier, and a multifunction machine having the functions of these devices.

  Many image forming apparatuses such as printers, facsimiles, and copiers on the market are provided with a paper tray on which the discharged paper is stacked below the paper discharge port. The sheet is dropped to the sheet tray and stacked on the sheet tray.

In such a paper tray, it is possible to continue to stack paper on the paper tray until the height of the paper stacked on the paper tray reaches the paper discharge port. Therefore, the stacking plate on which the sheet is loaded is biased from below by a spring so that as many sheets as possible can be stacked on the sheet tray, and the stacking plate sinks downward by the weight of the sheet. Paper trays have been proposed (see, for example, Patent Document 1 and Patent Document 2).
Japanese Patent No. 3323654 (page 3, FIG. 1) JP-A-5-17064 (page 3-4, FIG. 6)

  In the paper tray shown in Patent Document 1, for a small size paper with a light weight, even if the number of stacked sheets is large, it is not possible to sink the stacking plate so much. By placing it, a large number of sheets are stacked. However, if the stacking plate is lowered in advance as described above, the drop distance from the sheet discharge port to the sheet tray becomes long, so that it is difficult to align the direction of the sheets stacked on the sheet tray.

  Further, in the paper tray shown in Patent Document 2, a part of the above-described stacking plate is divided so that a small size paper is stacked on the part, and a part of the paper tray overlaps a small size paper. However, it is biased by a weak spring so that it sinks sufficiently. However, with this configuration, it is impossible to stack a large number of sheets by sinking the stacking plate with respect to a sheet having a size slightly larger than the size of the sheet that can be stacked on the part.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a paper tray that can stack a large amount of a plurality of types of paper having different sizes and that can easily align the direction of the stacked paper.

The paper tray of the present invention is a paper tray that receives the paper that is discharged from the paper discharge portion in a predetermined conveyance direction, and that slides and hits the paper rear end reference surface,
  A tray housing provided with the paper rear edge reference surface;
  A stacking plate that is provided in the tray casing and can freely move up and down to a predetermined upper limit;
  An extension plate attached to the tray housing side of the stacking plate, which is provided with a convex portion that extends and reduces the upper surface in response to a pulling operation. When normal-size paper is discharged, the tray housing An extension plate that is stored in the body and is drawn out from the tray housing when a paper of a size larger than the normal size is discharged;
  A paper stacking plate support portion having one end connected to the stacking plate and the other end connected to the tray housing and having a hinge structure for supporting the stacking plate so as to be movable up and down;
  A first elastic body, one end of which is fixed to the sheet stacking plate support and the other end of which is fixed to the tray housing;
  A second elastic body that has one end fixed to the sheet stacking plate support and the other end in contact with the surface of the extension plate on the tray housing side, and biases the stacking plate upward;
  When the upper plate extends the upper surface, the convex portion rides on the other end of the second elastic body to contract the second elastic body, and when the upper surface is reduced, the convex portion The amount of deformation of the second elastic body when the loading plate is at the upper limit is changed by extending the second elastic body off the other end of the second elastic body. It is characterized by.

According to the paper tray of the present invention, it is possible to stack paper of a larger size by extending the upper surface with the extension plate. Further, in order to load the large paper size if example embodiment, with respect to the extension plate, the operation for extending the top surface is performed, along with the operation, the amount of deformation of the upper Symbol elastic body, its the Rukoto is adjusted to the amount of deformation corresponding to the larger size.

  As described above, according to the present invention, it is possible to provide a paper tray in which a plurality of types of paper having different sizes can be stacked in large quantities and the orientation of the stacked paper can be easily aligned.

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

  FIG. 1 is an external view showing a paper tray according to an embodiment of the present invention together with a copier to which the paper tray is attached.

  The appearance shown in FIG. 1 is common to the first to fifth embodiments described below. In FIG. 1, the paper trays 100, 200, 300, 400, and The paper tray 100 of the first embodiment out of 500 is given as a representative example, and the appearance of the copier 1000 including the paper tray 100 is shown. Part (a) of FIG. 1 shows an overall external view of the copier 1000 including the paper tray 100, and part (b) of FIG. 1 shows an enlarged view around the paper tray 100. Yes.

  As shown in FIG. 1, the paper tray is inclined so as to be lowered toward the paper discharge unit 1100 of the copier 1000. The paper P discharged from the paper discharge unit 1100 in a predetermined discharge direction (see arrow A in the figure) slides down in the direction of arrow B along this inclination and is received by hitting the side wall of the paper tray.

  Here, the paper stacking board sinks according to the weight of the stacked paper. Thereby, a large amount of sheets can be stacked on the sheet stacking plate.

  In the following, each embodiment will be described focusing on the internal structure of the paper tray.

  FIG. 2 is a cross-sectional view showing the internal structure of the paper tray according to the first embodiment of the present invention. Part (a) of FIG. 2 shows a state in which a postcard size paper P1 is stacked on the paper stacking plate 110, and part (b) of FIG. 2 shows a postcard size on the paper stacking plate 110. A state in which a so-called normal size paper P2 larger than the paper stacking plate 110 is loaded is shown.

  The paper tray 100 includes a paper stacking plate 110, a housing 120, a spring 130, a spring adjustment unit 140, and a connecting shaft 150. Here, the sheet stacking plate 110, the casing 120, the spring 130, and the spring adjustment unit 140 correspond to examples of the stacking plate, the casing, the elastic body, and the adjustment mechanism, respectively, according to the present invention. 2A and 2B also show a schematic cross section of the paper discharge port 1100 shown in FIG.

  As shown in FIG. 2, the sheet stacking plate 110 is connected to the housing 120 by a connecting shaft 150 so as to be rotatable about the connecting shaft 150. However, a stopper (not shown) is provided at a predetermined position above the paper stacking plate 110 of the housing 120. The upward movement of the paper stacking plate 110 away from the housing 120 is caused by the paper stacking plate 110. With the position hitting the stopper as the upper limit, the sheet stacking plate 110 is restricted so as not to move beyond the upper limit. Here, the peripheral structure of the connecting shaft 150 corresponds to an example of a hinge structure according to the present invention.

  A spring 130 and a spring adjustment unit 140 are disposed between the paper stacking plate 110 and the housing 120. One end of the spring 130 is fixed to the back surface of the paper stacking plate 110 on the housing 120 side, and the other end is in contact with the spring adjustment unit 140. The paper stacking plate 110 is urged upward by the spring 130.

  The spring adjustment unit 140 is attached to the housing 120 so as to be slidable in the direction of arrow C1 shown in part (a) of FIG. 2 and in the direction of arrow C2 shown in part (b) of FIG. The spring adjustment unit 140 has an operation lever 140a that protrudes out of the housing 120. When the user moves the operation lever 140a in the direction of the arrow C1 or the direction of the arrow C2, the spring adjustment unit 140 moves in the direction of the arrow C1 or Slide in the direction of arrow C2. The spring adjustment unit 140 also has a convex portion 140 b that protrudes into the housing 120.

  As shown in part (b) of FIG. 2, when the user moves the operation lever 140a in the direction of arrow C2 and slides the spring adjustment unit 140 in the direction of arrow C2, one end of the spring 130 on the spring adjustment unit 140 side is It rides on the convex portion 140b and the spring 130 is contracted by the height of the convex portion 140b. At this time, the spring 130 urges the paper stacking plate 110 as much as the contracted amount. On the other hand, as shown in part (a) of FIG. 2, when the spring adjustment unit 140 slides in the direction of the arrow C1, one end of the spring 130 on the spring adjustment unit 140 side descends from the top of the projection 140b, and the spring 130 It extends by the height of the convex portion 140b. At this time, the spring 130 weakens the amount corresponding to the extension, and biases the paper stacking plate 110.

  Here, in this embodiment, as shown in part (a) of FIG. 2, when the postcard-size paper P1 is stacked on the paper stacking plate 110, it is in the extended state shown in part (a) of FIG. A spring that exerts an urging force that can sufficiently sink the paper stacking plate 110 is used as the spring 130 shown in FIG.

  As shown in part (a) of FIG. 2, when a postcard-sized paper P1 is discharged from the paper discharge port 1100 in the discharge direction A and stacked on the paper stacking plate 110, the paper stacking plate 110 has this A force F1 corresponding to the weight of the stacked paper P1 is applied to the position 110a corresponding to the center of gravity of the paper P1. At this time, around the connecting shaft 150, a force F1 and a moment D1 corresponding to the distance from the position 110a where the force F1 is applied to the connecting shaft 150 are generated, and the spring 130 is compressed in accordance with the moment D1. The paper stacking plate 110 sinks. Here, the postcard-size paper P1 is stacked at a position away from the connecting shaft 150 due to its small size. That is, the distance from the position 110a where the force F1 is applied to the connecting shaft 150 is long. However, since the paper P1 is very light, the force F1 is very small and the moment D1 is small, so the compressive force applied to the spring 130 is weak. As described above, in this embodiment, in this embodiment, a spring that exhibits an appropriate biasing force in the extended state is used as the spring 130 shown in FIG. Therefore, in this case, the spring adjustment unit 140 is slid in the direction of the arrow C1, and the spring 130 extends. As a result, the sheet stacking plate 110 sufficiently sinks, so that a large amount of sheets can be stacked.

  On the other hand, as shown in part (b) of FIG. 2, when a large size paper P2 is stacked on the paper stacking plate 110, it is closer to the connecting shaft 150 than when a postcard size paper P1 is stacked. A large force F2 corresponding to the heavy weight of the paper P2 is applied to the position 110b. In this case, the distance from the position 110b where the force F2 is applied to the connecting shaft 150 is short, but since the force F2 is large, a large moment D2 is generated around the connecting shaft 150, and the spring 130 is strongly compressed. Therefore, in this case, the spring adjusting unit 140 is slid in the direction of the arrow C2 so that the paper stacking plate 110 does not sink too much, and the spring 130 is contracted to strongly bias the paper stacking plate 110. As a result, the paper stacking plate 110 does not sink too much even with a large size paper P2, which is heavy, so that the falling distance of the paper P2 from the paper discharge port 1100 to the paper stacking plate 110 becomes too long. Disturbance of the orientation of the paper P2 is suppressed.

  As described above, according to the first embodiment of the present invention, the amount of subsidence of the paper stacking plate 110 is maintained at an appropriate amount of subsidence regardless of the size of the stacked paper. A large amount of each sheet can be stacked, and the direction of the stacked sheets can be easily aligned.

  Next, a second embodiment of the present invention will be described.

  FIG. 3 is a cross-sectional view showing the internal structure of the paper tray according to the second embodiment of the present invention. Part (a) of FIG. 3 shows a state in which normal-size paper P3 that fits on the paper stacking plate 110 is stacked, and part (b) of FIG. 3 shows a large size that protrudes from the paper stacking plate 110. A state in which the sheet P4 is loaded is shown. Here, among the components of the paper tray 200 of the second embodiment, the same components as those of the first embodiment shown in FIG. 2 are denoted by the same reference numerals as those in FIG.

  3 includes an extension plate 210 and a spring 220 corresponding to the extension plate 210 in addition to the paper stacking plate 110, the housing 120, and the connecting shaft 150 shown in FIG. . Here, the extension plate 210 corresponds to an example of the extension plate according to the present invention.

  The spring 220 shown in FIG. 3 has one end on the housing 120 side fixed to the housing 120 and the other end in contact with the back surface of the extension plate 210 on the housing 120 side.

  The extension plate 210 is attached to the paper stacking plate 110 so as to be slidable in the direction of arrow E1 shown in part (a) of FIG. 3 or in the direction of arrow E2 shown in part (b) of FIG. As shown in part (a) of FIG. 3, when the normal size paper P3 is discharged from the paper discharge port 1100, the extension plate 210 is slid by the user in the direction of arrow E1 and stored in the housing 120.

  On the other hand, as shown in part (b) of FIG. 3, when the large-size paper P4 larger than the paper stacking plate 110 is discharged, the extension plate 210 is slid in the direction of arrow E2 by the user and pulled out from the housing 120. Is done. Then, the paper P4 is stacked on the stacking surface in which the paper stacking plate 110 and the extension plate 210 are combined.

  Further, a convex portion 210 a protruding into the housing 120 is provided on the back surface of the extension plate 210. Here, the convex portion 210a corresponds to an example of an adjustment mechanism “integrated or interlocked with the extension plate” according to the present invention.

  When the extension plate 210 is housed in the housing 120 as shown in part (a) of FIG. 3, the convex portion 210 a of the extension plate 210 rides on one end of the spring 220 on the extension plate 210 side, The spring 220 is contracted by the height of the convex portion 210a. At this time, the spring 220 urges the paper stacking plate 110 as much as it is contracted by the convex portion 210a. On the other hand, as shown in part (b) of FIG. 3, when the extension plate 210 is pulled out, the extension plate 210 convex portion 210 a comes off from one end of the spring 220 on the extension plate 210 side, and the spring 220 is moved. It extends by the height of the convex part 210a. At this time, the spring 220 weakens the amount corresponding to the extension, and biases the paper stacking plate 110.

  Here, in the present embodiment, as shown in part (b) of FIG. 3, when large-size paper P4 is stacked on the paper stacking plate 110 and the extension plate 210, it is shown in part (b) of FIG. 3. A spring that exerts an urging force capable of appropriately sinking the paper stacking plate 110 and the extension plate 210 in the extended state is used as the spring 220 shown in FIG.

  As shown in part (a) of FIG. 3, when the normal size paper P3 is stacked on the paper stacking plate 110 with the extension plate 210 stored, the paper stacking plate 110 corresponding to the center of gravity of the paper P3. A force F3 corresponding to the weight of the paper P3 is applied to the position 110c. In this case, a moment D3 corresponding to the distance from the position 110b where the force F3 is applied to the connecting shaft 150 and the force F3 is generated around the connecting shaft 150. In this case, the spring 220 is more strongly compressed than in the case of part (b) of FIG. Therefore, in this embodiment, in this case, the spring 220 is contracted by the convex portion 210a so as to strongly bias the paper stacking plate 110 so that the paper stacking plate 110 does not sink too much. As a result, the orientation of the falling paper P3 due to the drop distance of the paper P3 from the paper discharge port 1100 to the paper stacking plate 110 becoming too long is suppressed.

  On the other hand, as shown in part (b) of FIG. 3, when the large size paper P4 is stacked on the paper stacking plate 110 and the extension plate 210 with the extension plate 210 pulled out, the large size paper P4. Is closer to the connecting shaft 150, the force F4 corresponding to the weight of the paper P4 is applied to the position 110d closer to the connecting shaft 150 than in the case of part (b) in FIG. In this case, since the paper P4 is heavy, the force F4 is large, but since the distance from the position 110d where the force F4 is applied to the connecting shaft 150 is short, the moment D4 generated around the connecting shaft 150 is small, and the spring 220 Is weakly compressed. As described above, in this embodiment, a spring that exhibits an appropriate urging force in the extended state is used as the spring 220 shown in FIG. Therefore, in this case, the protrusion 220a of the extension plate 210 is removed from the end of the spring 220 on the extension plate 210 side, so that the spring 220 extends. As a result, the sheet stacking plate 110 sufficiently sinks, so that a large amount of sheets can be stacked.

  As described above, according to the second embodiment of the present invention, it is possible to stack a large amount of a plurality of types of sheets having different sizes, and to easily align the directions of the stacked sheets.

  Next, a third embodiment of the present invention will be described.

  FIG. 4 is a cross-sectional view showing the internal structure of the paper tray according to the third embodiment of the present invention. Part (a) in FIG. 4 shows a state in which normal-size paper P3 is stacked, and part (b) in FIG. 4 shows a state in which large-size paper P4 is stacked. Yes.

  The paper tray 300 shown in FIG. 4 includes a paper stacking plate 310, a housing 320, an extension plate 330, a paper stacking plate support 340, a first connecting shaft 350, a second connecting shaft 360, and a first spring. 370 and a second spring 380. Here, the paper stacking plate 310, the housing 320, the extension plate 330, and the second spring 380 correspond to examples of the stacking plate, the housing, the extension plate, and the elastic body according to the present invention, respectively. The peripheral structure of each of the second connecting shafts 350 and 360 corresponds to an example of a hinge structure according to the present invention. Further, a convex portion 330a protruding into the casing 320 is provided on the back surface of the extension plate 330 on the casing 320 side, and this convex portion 330a is integrated or interlocked with the extension plate according to the present invention. This corresponds to an example of an adjustment mechanism.

  The paper stacking plate 310 is connected to the paper stacking plate support 340 by the first connecting shaft 350 so as to be rotatable about the first connecting shaft 350, and the paper stacking plate support 340 is connected by the second connecting shaft 360. The housing 320 is connected to the housing 320 so as to be rotatable about the second connecting shaft 360. With such a mechanism, the sheet stacking plate 310 is attached to the housing 320 so as to be able to move in the vertical direction in contact with and away from the housing 320. However, a stopper (not shown) is provided at a predetermined position above the paper stacking plate 310 of the housing 320, and the upward movement of the paper stacking plate 310 limits the position where the paper stacking plate 310 contacts this stopper to the upper limit. The sheet stacking plate 310 is regulated so as not to move beyond the upper limit.

  The extension plate 330 is attached to the paper stacking plate 310 so as to be slidable in the direction of arrow E1 shown in part (a) of FIG. 4 or in the direction of arrow E2 shown in part (b) of FIG. When the normal size paper P3 is discharged from the paper discharge port 1100, the extension plate 330 is stored in the housing 320, and when the large size paper P4 is discharged, the extension plate 330 is pulled out from the housing 320. Is done.

  The first spring 370 is disposed between the paper stacking plate support 340 and the housing 320, one end is fixed to the paper stacking plate support 340, and the other end is fixed to the housing 320. The first spring 370 indirectly biases the sheet stacking plate 310 upward via the sheet stacking plate support 340.

  The second spring 380 is disposed between the extension plate 330 attached to the paper stacking plate 310 and the paper stacking plate support 340, one end is fixed to the paper stacking plate support 340, and the other end is extended. It contacts the back surface of the plate 330. As shown in part (b) of FIG. 4, when the extension plate 330 is pulled out, the convex portion 330 a of the extension plate 330 rides on one end of the second spring 380 on the extension plate 330 side, and the second spring 380 is reduced by the height of the convex portion 330a. At this time, the second spring 380 urges the paper stacking plate 310 as much as it is contracted by the convex portion 330a. On the other hand, as shown in part (a) of FIG. 4, when the extension plate 330 is accommodated, the convex portion 330 a of the extension plate 330 comes off from one end of the second spring 380 on the extension plate 330 side, The second spring 380 extends by the height of the convex portion 330a. At this time, the second spring 380 urges the paper stacking plate 310 weakly by the extension.

  As shown in part (a) of FIG. 4, when a normal size paper P3 is stacked on the paper stacking plate 310 with the extension plate 330 stored, a force corresponding to the weight of the paper P3 is the first. Almost equally distributed and hooked on both the first and second springs 370 and 380, the two springs are evenly compressed. In the present embodiment, springs that generate an urging force that sufficiently sinks the paper stacking plate 310 in this state are used as the first and second springs 370 and 380.

  On the other hand, as shown in part (b) of FIG. 4, when the large size paper P4 is stacked on the paper stacking plate 310 and the extension plate 330 with the extension plate 330 pulled out, the large size paper P4 is placed. Is almost close to the second spring 380, most of the force corresponding to the weight of the paper P4 is applied to the second spring 380, and the second spring 380 is strongly compressed. Therefore, in this embodiment, in this case, the first spring 370 side of the paper stacking plate 310 does not sink sufficiently, and the second spring 380 side of the paper stacking plate 310 does not sink too much. The two springs 380 are contracted by the convex portion 330 a so as to urge the paper stacking plate 310 strongly. As a result, the second spring 380 side of the paper stacking plate 310 is pushed back by the second spring 380, so that the second spring 380 side of the paper stacking plate 310 is prevented from excessively sinking. Further, a force is applied to the first spring 370 as much as the second spring 380 side of the sheet stacking plate 310 is pushed back. As a result, the first spring 370 side of the sheet stacking plate 310 also sinks sufficiently.

  As a result, the settlement of the first spring 370 side of the paper stacking plate 310 is insufficient, and it becomes impossible to stack a large amount of paper P4, or the paper stacking plate 310 is inclined to the second spring 380 side. Such a problem that the paper P4 falls or the directions of the stacked paper P4 are difficult to align is avoided.

  As described above, according to the third embodiment of the present invention, it is possible to stack a large amount of each of a plurality of types of sheets having different sizes, and to easily align the stacked sheets.

  Next, a fourth embodiment of the present invention will be described.

  FIG. 5 is a cross-sectional view showing the internal structure of the paper tray according to the fourth embodiment of the present invention. Part (a) in FIG. 5 shows a state in which normal size paper P3 is stacked, and part (b) in FIG. 5 shows a state in which large size paper P4 is stacked. Yes.

  5 includes a paper stacking plate 410, a housing 415, an extension plate 420, a first paper stacking plate support 425, a second paper stacking plate support 430, and a first connection. A shaft 435, a housing side roller 440, a paper stacking plate side roller 445, a second connection shaft 450, a third connection shaft 455, and a spring 460 are provided. Here, the sheet stacking plate 410, the casing 415, the extension plate 420, and the spring 460 correspond to examples of the stacking plate, casing, extension plate, and elastic body according to the present invention, respectively. The peripheral structure of each of the connecting shafts 435 and 450 corresponds to an example of a hinge structure according to the present invention. Further, the back surface of the extension plate 420 on the housing 415 side is provided with a convex portion 420a protruding into the housing 415. The convex portion 420a is integrated or interlocked with the extension plate according to the present invention. This corresponds to an example of an adjustment mechanism.

  The sheet stacking plate 410 is connected to one end of the first sheet stacking plate support 425 by the first connecting shaft 435 so as to be rotatable around the first connecting shaft 435. A housing side roller 440 is attached to another end of the first paper stacking plate support 425, and the housing side roller 440 is in contact with the inner wall of the housing 415. One end of the second paper stacking plate support 430 is connected to the housing 415 by a second connecting shaft 450 so as to be rotatable about the second connecting shaft 450. A paper stacking plate-side roller 445 is attached to another end of the second paper stacking plate support 430, and the paper stacking plate-side roller 445 is in contact with the back surface of the paper stacking plate 410. The first paper stacking plate support portion 425 and the second paper stacking plate support portion 430 are connected to each other by a third connecting shaft 455 so as to be rotatable. With such a mechanism, the sheet stacking plate 410 is attached to the housing 415 so as to be able to move in the vertical direction in contact with and away from the housing 415. However, a stopper (not shown) is provided at a predetermined position above the paper stacking plate 410 in the housing 415. The upward movement of the paper stacking plate 410 limits the position where the paper stacking plate 410 hits this stopper to the upper limit. The sheet stacking plate 410 is regulated so as not to move beyond the upper limit.

  The extension plate 420 is attached to the paper stacking plate 410 so as to be slidable in the direction of arrow E1 shown in part (a) of FIG. 5 or in the direction of arrow E2 shown in part (b) of FIG. When the normal size paper P3 is discharged from the paper discharge port 1100, the extension plate 420 is accommodated in the housing 415. When the large size paper P4 is discharged, the extension plate 420 is pulled out from the housing 415. Is done.

  The spring 460 is disposed between the extension plate 420 attached to the paper stacking plate 410 and the housing 415, one end is fixed to the housing 415, and the other end is in contact with the back surface of the extension plate 420. As shown in part (b) of FIG. 5, when the extension plate 420 is pulled out, the projection 420 a of the extension plate 420 rides on one end of the spring 460 on the extension plate 420 side, and the spring 460 is placed on the projection. Shrink by the height of 420a. At this time, the spring 460 urges the sheet stacking plate 410 as much as it is contracted by the convex portion 420a. On the other hand, as shown in part (a) of FIG. 4, when the extension plate 420 is accommodated, the convex portion 420 a of the extension plate 420 comes off from one end of the spring 460 on the extension plate 420 side, and the spring 460. Extends by the height of the convex portion 420a. At this time, the spring 460 biases the paper stacking plate 410 as weakly as it extends.

  As shown in part (a) of FIG. 5, when the normal size paper P3 is stacked on the paper stacking plate 410 with the extension plate 420 stored, a force corresponding to the weight of the paper P3 is applied by the spring 460. And the spring 460 is compressed. In this embodiment, a spring that generates an urging force that sufficiently sinks the sheet stacking plate 410 in this state is used as the spring 460 in FIG.

  On the other hand, as shown in part (b) of FIG. 5, when the large size paper P4 is stacked on the paper stacking plate 410 and the extension plate 420 with the extension plate 420 pulled out, the large size paper P4 is placed. Is heavy, the spring 460 is strongly compressed. Therefore, in this embodiment, in this case, the spring 460 is contracted by the convex portion 420a so as to strongly bias the paper stacking plate 410 so that the paper stacking plate 410 does not sink too much. As a result, the orientation of the falling paper P3 due to the drop distance of the paper P3 from the paper discharge port 1100 to the paper stacking plate 410 becoming too long is suppressed.

  As described above, according to the fourth embodiment of the present invention, a plurality of types of sheets having different sizes can be stacked in large quantities, and the directions of the stacked sheets can be easily aligned.

  Next, a fifth embodiment of the present invention will be described.

  FIG. 6 is a sectional view showing the internal structure of the paper tray according to the fifth embodiment of the present invention. Part (a) in FIG. 6 shows a state in which normal size paper P3 is stacked, and part (b) in FIG. 6 shows a state in which large size paper P4 is stacked. Yes.

  A sheet tray 500 shown in FIG. 6 includes a sheet stacking plate 510, a housing 520, an extension plate 530, a first spring 540, and a second spring 550. Here, the sheet stacking plate 510, the casing 520, the extension plate 530, and the second spring 550 correspond to examples of the stacking plate, casing, extension plate, and elastic body according to the present invention, respectively. Further, a convex portion 530a protruding into the housing 520 is provided on the back surface of the extension plate 530 on the housing 520 side, and the convex portion 530a is integrated or interlocked with the extension plate according to the present invention. This corresponds to an example of an adjustment mechanism.

  An extension plate 530 is attached to the back surface of the paper stacking plate 410 on the housing 520 side so as to be slidable in the direction of arrow E1 shown in part (a) of FIG. 5 or in the direction of arrow E2 shown in part (b) of FIG. Yes.

  In addition, first and second springs 540 and 550 are disposed between the back surface of the extension plate 530 and the housing 520. One end of each spring is fixed to the housing 520, and the other end is in contact with the back surface of the extension plate 530 to support the sheet stacking plate 410 through the extension plate 530. As shown in part (b) of FIG. 6, when the extension plate 530 is pulled out, the convex portion 530 a of the extension plate 530 rides on one end of the second spring 550 on the extension plate 420 side and is second. The spring 530a is contracted by the height of the convex portion 530a. Then, the second spring 550 urges the paper stacking plate 510 as much as it is contracted by the convex portion 530a. On the other hand, as shown in part (a) of FIG. 6, when the extension plate 530 is stored, the convex portion 530 a of the extension plate 530 is detached from one end of the second spring 550 on the extension plate 420 side. The spring 550 extends by the height of the convex portion 530a. At this time, the second spring 550 urges the paper stacking plate 510 as weak as the extension.

  As shown in part (a) of FIG. 6, when the normal size paper P3 is stacked on the paper stacking plate 510 in a state where the extension plate 530 is stored, a force corresponding to the weight of the paper P3 is the first. Almost evenly distributed and hooked on both the first and second springs 540, 550, the two springs are evenly compressed. In the present embodiment, springs that generate a biasing force that sufficiently sinks the paper stacking plate 510 in this state are used as the first and second springs 540 and 550.

  On the other hand, as shown in Part (b) of FIG. 6, when the large size paper P4 is stacked on the paper stacking plate 510 and the extension plate 530 with the extension plate 530 pulled out, the large size paper P4 is loaded. Since the center of gravity is close to the second spring 550, most of the force corresponding to the weight of the paper P4 is applied to the second spring 550, and the second spring 550 is strongly compressed. Therefore, in this embodiment, in this case, the first spring 540 side of the paper stacking plate 510 is not sufficiently depressed, and the second spring 550 side of the paper stacking plate 510 is not excessively depressed. The two springs 550 are contracted by the convex portion 530a so as to urge the paper stacking plate 510 strongly. As a result, the second spring 550 side of the paper stacking plate 510 is pushed back by the second spring 550, so that the second spring 550 side of the paper stacking plate 510 is prevented from excessively sinking. Further, a force is applied to the first spring 540 as much as the second spring 550 side of the paper stacking plate 510 is pushed back. As a result, the first spring 540 side of the sheet stacking plate 510 is also sufficiently sunk.

  As a result, the settlement of the sheet stacking plate 510 on the first spring 540 side is insufficient, and a problem such that the sheet P4 cannot be stacked in large quantities, or the sheet stacking plate 510 is inclined toward the second spring 550 side. Such a problem that the paper P4 falls or the stacked paper P4 is difficult to align is avoided.

  As described above, according to the fifth embodiment of the present invention, it is possible to stack a plurality of types of sheets having different sizes and to easily align the directions of the stacked sheets.

  In the above description, as an example of the adjusting mechanism according to the present invention, the spring adjusting portion that changes the length of the spring for urging the paper stacking plate in two stages and the convex portion of the extension plate are described. This is not a limitation. The adjustment mechanism of the present invention may be, for example, a spring adjustment unit provided with a plurality of types of projections having different heights, or such a plurality of types of projections provided on an extension plate. In this case, the length of the spring is changed to a length corresponding to the height of each of the plurality of types of convex portions, and thereby the urging force against the sheet stacking plate is also changed in a plurality of stages.

  In the above description, as an example of the elastic body referred to in the present invention, a spring that is contracted when a sheet is stacked on a sheet stacking plate is described. However, the present invention is not limited to this. The elastic body of the present invention may be, for example, a spring attached so as to extend when a sheet is stacked on a sheet stacking plate, or, for example, a rubber that is shrunk when a sheet is stacked on the sheet stacking plate, The rubber may be attached so as to extend when a sheet is loaded on the sheet stacking plate.

  Further, in the above, as an example of the adjustment mechanism referred to in the present invention, the spring adjustment portion that changes the length of the spring by the user directly moving it manually and the convex portion of the extension plate are mentioned. It is not limited to. The adjustment mechanism of the present invention may be, for example, an adjustment mechanism that changes the length of the spring indirectly through an electrical or mechanical transmission mechanism when the user performs a button operation or the like.

1 is an external view showing a paper tray according to an embodiment of the present invention together with a copier to which the paper tray is attached. It is sectional drawing which shows the internal structure of the paper tray of 1st Embodiment of this invention. It is sectional drawing which shows the internal structure of the paper tray of 2nd Embodiment of this invention. It is sectional drawing which shows the internal structure of the paper tray of 3rd Embodiment of this invention. It is sectional drawing which shows the internal structure of the paper tray of 4th Embodiment of this invention. It is sectional drawing which shows the internal structure of the paper tray of 5th Embodiment of this invention.

Explanation of symbols

100, 200, 300, 400, 500 Paper tray 110, 310, 410, 510 Paper stacking plate 110a, 110b, 110c, 110d Position 120, 320, 415, 520 Housing 130, 220, 460 Spring 140 Spring adjustment part 140a Operation Lever 140b, 210a, 330a, 420a, 530a Protruding portion 150 Connection shaft 210, 330, 420, 530 Extension plate 340 Paper stacking plate support portion 350, 435 First connection shaft 360, 450 Second connection shaft 370, 540 First spring 380, 550 Second spring 425 First paper stacking plate support portion 430 Second paper stacking plate support portion 440 Housing side roller 445 Paper stacking plate side roller 455 Third connecting shaft

Claims (1)

In the paper tray that receives the paper that is ejected from the paper ejection part in the predetermined transport direction and slides and stops against the paper rear edge reference surface,
A tray housing provided with the paper trailing edge reference surface;
A stacking plate that is provided in the tray casing and can freely move up and down to a predetermined upper limit;
An extension plate attached to the tray housing side of the stacking plate and provided with a convex portion that extends and reduces the upper surface in response to a pulling operation, and when the normal size paper is discharged, An extension plate that is stored in the body and pulled out of the tray housing when a paper of a size larger than the normal size is discharged;
A paper stacking plate support portion having one end connected to the stacking plate and the other end connected to the tray housing and having a hinge structure for supporting the stacking plate so as to be movable up and down;
A first elastic body, one end of which is fixed to the paper stacking plate support and the other end of which is fixed to the tray housing;
A second elastic body, one end of which is fixed to the sheet stacking plate support and the other end of which is in contact with the surface of the extension plate on the tray housing side, and biases the stacking plate upward ;
When the upper plate extends the upper surface, the convex portion rides on the other end of the second elastic body to contract the second elastic body, and when the upper surface is reduced, the convex portion The amount of deformation of the second elastic body when the stacking plate is at the upper limit is changed by extending the second elastic body off the other end of the second elastic body. Paper tray characterized by.

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