JP2011235970A - Sheet receiving mechanism and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet receiving mechanism wherein a limitation on the number of stacked sheets is reduced.SOLUTION: A sheet discharge part 37 includes a sheet receiving part 51, a projected part 52, and a sheet pressing member 53. On the sheet receiving part 51, sheets 7 discharged from a discharge port 39 are stacked. The projected part 52 projects in the thickness direction of the sheet 7 at the receiving part 51. The sheet pressing member 53 includes sheet pressing parts 541 and 542. The sheet pressing parts 541 and 542 press the sheets 7 on the sheet receiving part 51 toward the sheet receiving part 51 at two places sandwiching the projected part 52 in a cross direction. The sheet pressing parts 541 and 542 can swing in the thickness direction of the sheet 7.

Description

  The present invention relates to a sheet receiving mechanism applicable to an image forming apparatus.

  2. Description of the Related Art Image forming apparatuses such as copiers, printers, and facsimile machines are provided with a sheet discharge tray that receives sheets discharged from a discharge port after printing. The sheet discharged onto the sheet discharge tray may be curled due to evaporation of moisture, for example. In that case, the curled sheet prevents further discharge of the sheet from the discharge port.

  The ink jet recording apparatus of Patent Document 1 includes a discharge tray and a discharge guide. The discharge tray is bent so as to protrude upward near the center in the width direction (the direction that is horizontal and perpendicular to the sheet conveyance direction). The discharge guide is disposed at a predetermined interval between the discharge guide and the discharge tray in the sheet thickness direction. The discharge guide has a shape extending in the sheet conveyance direction, and is fixed to both sides of the discharge tray in the width direction.

  Patent Document 1 describes that the sheet discharged to the discharge tray tends to curl upward as the ink is dried, but is curled by the discharge guide. Further, in Patent Document 1, since the sheet is dried so that the vicinity of the center of the discharge tray is convex upward, the sheet is dried in a state of convex upward, so that curling of the sheet is suppressed. It is stated.

Japanese Patent Laid-Open No. 11-193163

  The discharge guide of Patent Document 1 has a problem that it is difficult for the user to take out the sheet because the position with respect to the discharge tray is fixed. Further, the number of sheets that can be stacked on the discharge tray is also limited. Furthermore, since the discharge guides are provided at both ends of the discharge tray in the width direction, applicable sheets are limited to those having a certain size in the width direction. In order to deal with a small sheet, it is necessary to increase the size of the discharge guide in the width direction, and it becomes more difficult to take out the sheet from the discharge tray.

  An object of the present invention is to provide a sheet receiving mechanism in which the restriction on the number of stacked sheets is relaxed.

  Hereinafter, a plurality of modes will be described as means for solving the problems. These aspects can be arbitrarily combined as necessary.

  A sheet receiving mechanism according to an aspect of the present invention is a sheet receiving mechanism provided for a device for discharging a sheet, and includes a sheet receiving portion, a convex portion, and a sheet pressing member. Sheets to be discharged are stacked on the sheet receiving portion. The convex portion is provided in the sheet receiving portion and protrudes in the thickness direction of the sheet. The sheet pressing member includes a sheet pressing portion. The sheet pressing portion presses the sheet toward the sheet receiving portion in at least two places sandwiching the convex portion in the first direction intersecting the sheet discharging direction. The sheet pressing portion can swing in the thickness direction of the sheet.

  In this sheet receiving mechanism, the height of both ends of the sheet in the first direction is suppressed by the sheet being held in a convex shape by the convex portion and the sheet pressing portion. In addition, since the sheet presser can swing in the sheet thickness direction, it moves away from the sheet receiver when the number of stacked sheets is large, and moves closer to the sheet receiver when the number of sheets stacked is small. can do. Therefore, the sheet receiving mechanism can cope with fluctuations in the number of stacked sheets. Furthermore, when the sheets stacked on the sheet receiving portion are taken out, the user can easily take out the sheets by moving the sheet pressing portion in a direction away from the sheet receiving portion.

  The sheet pressing member may be provided such that the second end is rotatable about the first end, and the sheet pressing portion may be provided at the second end. Accordingly, the sheet pressing portion is provided so as to be swingable with a simple configuration.

  The convex portion may be provided at a central portion of the sheet receiving portion in the first direction. As a result, sheets having different sizes in the first direction are also held by the convex portions so as to be convex upward.

  Two or more sheet pressing portions may be provided on one sheet pressing member. Further, the sheet receiving mechanism may include two or more sheet pressing members.

  The sheet pressing member may be disposed near the upstream end in the sheet discharging direction with respect to the sheet receiving portion. As a result, the sheet pressing unit can press even sheets having different sizes in the sheet discharge direction.

  Further, the sheet receiving mechanism can be applied to an image forming apparatus. The image forming apparatus includes a housing, an image forming unit, a sheet conveying unit, a sheet receiving unit, a convex portion, and a sheet pressing member. The housing includes a paper discharge port for discharging the sheet. The image forming unit is disposed in the housing and forms an image on the sheet. The sheet conveying unit discharges the sheet on which the image has been formed to the outside of the housing through the sheet discharge port. The sheet receiving unit is disposed downstream of the sheet discharge port in the sheet discharging direction by the sheet conveying unit. With this arrangement, the discharged sheets are stacked on the sheet receiving portion. A convex part is a shape which is provided in a sheet | seat receiving part and protrudes in the thickness direction of a sheet | seat. The sheet pressing member includes a sheet pressing portion that presses the sheet toward the sheet receiving portion at at least two positions sandwiching the convex portion in the first direction intersecting the sheet discharging direction. The sheet pressing portion is provided so as to be able to swing in the thickness direction of the sheet.

  In the sheet receiving mechanism of the present invention, the sheet is held in a convex shape protruding upward by the convex portion and the sheet pressing portion. That is, the height of both ends of the sheet in the first direction is suppressed on the sheet receiving portion. In addition, since the sheet pressing portion is movable in the sheet thickness direction, it is possible to cope with fluctuations in the number of stacked sheets. Furthermore, when the sheets stacked on the sheet receiving portion are taken out, the sheet pressing portion moves in the sheet thickness direction, so that the user can easily take out the sheets.

1 is a schematic diagram of an entire image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a front view schematically showing a configuration of a paper discharge unit according to the first embodiment. FIG. 3 is a side view schematically illustrating a configuration of a paper discharge unit according to the first embodiment. The side view which shows typically the structure of the paper discharge part which concerns on 2nd Embodiment. The side view which shows typically the structure of the paper discharge part which concerns on 3rd Embodiment. FIG. 6 is a front view illustrating the position of the sheet pressing unit when sheets are stacked on the sheet receiving unit in the paper discharge unit according to the first embodiment.

I. First Embodiment (1) Structure of Image Forming Apparatus An image forming apparatus will be described with reference to FIG. FIG. 1 is a schematic diagram of an entire image forming apparatus including an embodiment according to the present invention. Hereinafter, in order to clarify the directional relationship in the image forming apparatus 1, the directions for the worker standing on the front surface (front side in FIG. 1) of the image forming apparatus 1 are the left-right direction, the front-rear direction, and the vertical direction. . That is, the “left-right direction” refers to the left-right direction in FIG. The “front-rear direction” is a direction perpendicular to the paper surface of FIG. 1, and the front indicates the front of FIG. 1 and the rear indicates the rear of FIG. The “vertical direction” refers to the vertical direction in FIG.

The image forming apparatus 1 includes an image reading device 2 and an image forming device main body 3.
The image reading apparatus 2 includes an image reading unit 21 and a document cover 22. The image reading unit 21 is a device that reads image data of a document, and is a so-called flatbed scanner. The image reading unit 21 includes a light source 23, a plurality of reflecting mirrors 24, and a scanner unit 25. In the image reading unit 21, the light irradiated and reflected from the light source 23 onto the original on the platen glass 26 is guided to the scanner unit 25 while being reflected by the plurality of reflecting mirrors 24. The document cover 22 is rotatably disposed on the image reading unit 21.

  The image forming apparatus main body 3 includes a housing 31 and other devices and mechanisms inside the housing 31. Specifically, the image forming apparatus main body 3 includes an image forming unit 32, a fixing device 33, a sheet conveying unit (sheet conveying unit) 34, a sheet feeding cassette 35, a manual sheet feeding tray 36, and a sheet discharging unit (sheet receiving mechanism). 37).

  The image forming unit 32 forms an image on a sheet (sheet) P based on image data of a document read by the image reading device 2 and image data sent from a personal computer. The image forming unit 32 includes a photosensitive drum 40, a charger 41, an exposure head 42, a developing device 43, a transfer roller 44, and a cleaning roller 45.

  The photosensitive drum 40 is a device that forms an electrostatic latent image on the surface. The photosensitive drum 40 is a columnar member that is rotatably provided. The photosensitive drum 40 is rotated counterclockwise in FIG. 1 about a rotation axis perpendicular to the paper surface direction of FIG. 1 by a driving device (not shown). The charging device 41, the exposure head 42, the developing device 43, the transfer roller 44, and the cleaning roller 45 are provided in this order in the rotation direction of the photosensitive drum 40.

  The charger 41 uniformly charges the surface of the photosensitive drum 40 to a predetermined potential.

  The exposure head 42 draws an electrostatic latent image along the image data by irradiating the surface of the charged photosensitive drum 40 with light. The exposure head 42 includes, for example, an LED (Light Emitting Diode) as a light source.

  The developing device 43 supplies toner to the electrostatic latent image on the photosensitive drum 40 and develops the electrostatic latent image. In the developing device 43, a predetermined potential is applied to the toner. Based on the difference between the potential and the potential of the electrostatic latent image, toner is attached to the electrostatic latent image, and the electrostatic latent image is visualized. In this embodiment, image formation is performed using negatively charged toner, but positively charged toner may be used.

The transfer roller 44 is disposed to face the photosensitive drum 40 and transfers the toner image on the photosensitive drum 40 onto the paper 7.
The cleaning roller 45 removes toner remaining on the outer peripheral surface of the photosensitive drum 40 that has not been transferred.

The fixing device 33 is a device that fixes the toner image on the paper 7 by applying heat and pressure to the paper 7 after the transfer. The fixing device 33 includes a heating roller 61 and a pressure roller 63.
The pressure roller 63 includes a metal roller shaft and an elastic member provided around the roller shaft. The pressure roller 63 is rotatably supported by the apparatus main body and is biased by the heating roller 61 by a biasing member (not shown) to form a nip portion 65. The pressure roller 63 is driven to rotate when the heating roller 61 rotates.

The paper transport unit 34 includes a transport path and a plurality of rollers. The paper transport unit 34 transports the paper 7 along the transport path by a roller, so that a paper discharge unit passes through the image forming unit 32 and the fixing device 33 from a paper feed cassette 35 or a manual paper feed tray 36 described later. The sheet 7 is conveyed up to 37. The paper 7 is discharged from a paper discharge port 39 provided in the housing 31 to a paper discharge unit 37 described later by the paper transport unit 34. The paper discharge port 39 is an opening that is long in the front-rear direction (the direction perpendicular to the paper surface in FIG. 1), and the length in the front-rear direction of the paper discharge port 39 corresponds to the width of the maximum size paper.
Note that the paper transport unit 34 discharges paper of different sizes so that the center of the paper 7 is aligned with the center of the paper discharge port 39 in the width direction. That is, the sheet 7 is discharged so that the center in the width direction matches the center in the width direction of a sheet receiving portion 51 described later.

The sheet feeding cassette 35 accommodates a bundle of sheets 7 before image formation. The paper feed cassette 35 is provided so as to be able to be taken in and out of the housing 31.
A special paper such as a back paper is placed on the manual paper feed tray 36.

(2) Paper discharge unit 37
The paper discharge unit 37 will be described with reference to FIGS. FIG. 2 is a front view of the paper discharge unit 37, and FIG. 3 is a side view of the paper discharge unit 37.

  The paper discharge unit 37 is a part that receives the paper 7 discharged from the paper discharge port 39 after the image is formed. The paper discharge unit 37 is provided on the upper surface of the housing 31 on the downstream side in the discharge direction 101 with respect to the paper discharge port 39. The discharge direction 101 is a direction parallel to the left-right direction. The paper discharge unit 37 includes a sheet receiving part 51, a convex part 52, a sheet pressing member 53, and a shaft 55.

  The sheet receiving portion 51 is a portion on which the sheets 7 are stacked. The width in the front-rear direction of the sheet receiving portion 51 is equal to or greater than the width in the front-rear direction of the paper discharge port 39, and can accept paper 7 of any size that can be discharged from the paper discharge port 39. As shown in FIG. 2, the sheet receiving portion 51 has an inclination that is lower on the upstream side (right side in FIG. 2) in the paper discharge direction 101. Due to this inclination, the sheets 7 are stacked in alignment with the right end of the sheet receiving portion 51.

  As shown in FIGS. 2 and 3, the convex portion 52 is a portion that is provided on the surface of the sheet receiving portion 51 that contacts the paper 7 and projects upward. In the present embodiment, the convex portion 52 is formed integrally with the sheet receiving portion 51. However, the convex portion 52 may be formed as a separate member and attached to the sheet receiving portion 51. The convex part 52 is arranged so that a cross section perpendicular to the left-right direction is an isosceles triangle and a vertex corresponding to the apex angle faces upward. The convex portion 52 is provided at the center portion of the sheet receiving portion 51 in the front-rear direction, that is, substantially at the center of the paper discharge port 39 in the front-rear direction. The convex portion 52 is continuous from the left end to the right end of the sheet receiving portion 51. The right end of the convex portion 52 has an inclined shape that descends toward the sheet receiving portion 51.

  The sheet pressing member 53 is a member that presses the paper 7 from above. As shown in FIGS. 2 and 3, the sheet pressing member 53 is a member on an elongated flat plate, and the second end 59 is swingably provided around the first end 58 in the longitudinal direction.

Specifically, a shaft 55 is provided at the first end 58 of the sheet pressing member 53. Further, the shaft 55 is fixed in the casing 31 at a position above the sheet receiving portion 51 and near the upstream end of the sheet receiving portion 51 in the discharge direction 101 (closer to the right end of the sheet receiving portion 51). . That is, the first end 58 of the sheet pressing member 53 is inserted into the housing 31 from the opening 311 provided in the housing 31 in the vicinity of the paper discharge port 39.
In addition, "offset" means that it is closer to one side than the midpoint of the member in one direction. That is, “near the upstream end of the sheet receiving portion 51” means closer to the upstream end of the sheet receiving portion 51 than the center of the sheet receiving portion 51 in the discharge direction 101.

  The second end 59 of the sheet pressing member 53 is a free end that can rotate around the shaft 55. The second end 59 is disposed downstream of the first end 58 in the discharge direction 101. The second end 59 of the sheet pressing member 53 is arranged outside the housing 31, and contacts the sheet receiving portion 51 when the sheet 7 is not loaded by the weight of the sheet pressing member 53, and the sheet 7 is loaded. Sometimes it contacts the paper 7.

The edge of the second end 59 of the sheet pressing member 53 has a recess 57 that is recessed toward the first end 58 as shown in FIG. The shape of the concave portion 57 is formed in an isosceles triangle shape so as to correspond to the convex shape of the convex portion 52. The concave portion 57 is provided so as to straddle the convex portion 52. In other words, the sheet pressing member 53 has, at the second end 59, sheet pressing portions 541 and 542 which are two convex portions arranged so as to sandwich the convex portion 52 from both sides in the front-rear direction.
With this arrangement, as shown in FIG. 3, the sheet pressing portions 541 and 542 are in contact with the sheet 7 in the front-rear direction of the convex portion 52. The sheet pressing portions 541 and 542 press the paper 7 toward the sheet receiving portion 51 by the weight of the sheet pressing member 53. The sheet 7 is held in a convex shape protruding upward by being pressed by the sheet pressing portions 541 and 542. As a result, the height of both ends in the width direction of the sheet 7 is suppressed. In this way, the paper discharge port 39 is prevented from being blocked by the curled paper 7. Accordingly, it is difficult to prevent the next sheet 7 from being discharged from the sheet discharge port 39, and the sheet can be discharged smoothly.

As the sheet pressing member 53 rotates about the shaft 55, the sheet pressing portions 541 and 542 can swing in the thickness direction of the paper 7 on the sheet receiving portion 51, that is, in the vertical direction. Accordingly, the distance between the sheet pressing portions 541 and 542 and the sheet receiving portion 51 can be changed in the vertical direction.
Therefore, as shown in FIG. 6, when the number of stacked sheets 7 on the sheet receiving portion 51 increases, the sheet pressing portions 541 and 542 can be lifted by the stacked sheets and moved upward. In this way, the sheet pressing portions 541 and 542 can fulfill the function of pressing the paper even when the number of the papers 7 changes.
Further, when the user tries to take out the paper 7 from the paper discharge unit 37, the sheet pressing units 541 and 542 easily move upward. Therefore, the user can easily take out the paper 7 from the paper discharge unit 37.

  As described above, the sheet pressing member 53 is disposed above the sheet receiving portion 51 and in the vicinity of the upstream end portion (the right end portion in FIG. 2) of the sheet receiving portion 51 in the discharge direction 101. That is, the sheet pressing member 53 is provided in the vicinity of the paper discharge port 39. With this arrangement, the sheet pressing portions 541 and 542 come into contact with the sheet 7 in the vicinity of the sheet discharge outlet 39, that is, in the vicinity of the right end portion of the sheet receiving portion 51. As described above, since the sheets 7 are stacked close to the right end side of the sheet receiving portion 51, the sheet pressing member 53 (sheet pressing portions 541 and 542) can correspond to sheets of various sizes. In other words, the position of the sheet pressing member is such a position that the sheet pressing portions 541 and 542 can press the minimum size paper. Specifically, the distance between the sheet pressing portions 541 and 542 and the right end of the sheet receiving portion 51 is arranged to be smaller than the minimum value of the sheet length in the discharge direction 101.

(3) Features The embodiment described above can be expressed as follows.
The paper discharge unit 37 includes a sheet receiving part 51, a convex part 52, and a sheet pressing member 53. In the sheet receiving portion 51, the paper 7 discharged from the paper discharge port 39 is stacked. The convex portion 52 projects upward in the sheet receiving portion 51. The sheet pressing member 53 includes sheet pressing portions 541 and 542. Each of the sheet pressing portions 541 and 542 presses the sheet 7 on the sheet receiving portion 51 toward the sheet receiving portion 51 at two positions sandwiching the convex portion 52 in the front-rear direction. The sheet pressing portions 541 and 542 can swing in the vertical direction.

  The sheet 7 is held in a convex shape protruding upward by the convex portion 52 and the sheet pressing portions 541 and 542. That is, the height of both ends of the sheet 7 in the front-rear direction on the sheet receiving portion 51 is suppressed. Accordingly, the paper discharge port 39 of the image forming apparatus 1 is prevented from being blocked by the paper 7, and the next paper is discharged smoothly. Further, since the sheet pressing portions 541 and 542 are movable in the vertical direction, it is possible to cope with fluctuations in the number of sheets 7 stacked. Further, when the sheets 7 stacked on the sheet receiving portion 51 are taken out, the sheet pressing portions 541 and 542 move upward, so that the user can take out the sheets 7.

  As an example of a configuration in which the sheet pressing portions 541 and 542 are swingable, the sheet pressing member 53 is provided with a second end 59 that is rotatable about the first end 58, and the sheet pressing portions 541 and 542 are provided. A second end 59 is provided.

  The convex portion 52 is provided at the center of the sheet receiving portion 51 in the discharge direction 101. As a result, it is possible to obtain an effect that curling can be effectively suppressed even for paper having different sizes in the width direction. In particular, in the present embodiment, the sheet 7 is discharged with respect to the sheet receiving portion 51 so that the center of the sheet 7 is aligned with the central portion of the sheet receiving portion 51 in the width direction. The sheet pressing portions 541 and 542 are arranged so as to press the paper 7 in the vicinity of the convex portion 52 in the width direction, so that a higher effect can be obtained.

  In the present embodiment, as a specific configuration of the sheet pressing member, one sheet pressing member 53 is provided with two sheet pressing portions 541 and 542. However, as will be described later, two or more sheet pressing members having one or more sheet pressing portions may be provided.

  The sheet pressing member 53 is disposed closer to the upstream end in the sheet discharge direction than the sheet receiving portion 51 (near the right end in FIG. 2).

  Further, the image forming apparatus 1 includes a casing 31, an image forming unit 32, a paper transport unit 34, and a paper discharge unit 37. The housing 31 includes a paper discharge port 39 that is an opening. The image forming unit 32 is disposed in the housing 31 and forms an image on a sheet. The paper transport unit 34 discharges the paper 7 on which the image has been formed to the outside of the housing 31 through the paper discharge port 39. The paper discharge unit 37 includes a sheet receiving part 51, a convex part 52, and a sheet pressing member 53. The sheet receiving unit 51 is disposed downstream of the paper discharge port 39 in the paper discharge direction 101 by the paper transport unit 34 and receives the discharged paper. The convex part 52 is provided in the sheet receiving part. The sheet pressing member 53 includes sheet pressing portions 541 and 542 that press the paper 7 toward the sheet receiving portion 51 at two positions sandwiching the convex portion 52 in the front-rear direction which is an example of the first direction intersecting the discharge direction 101. ing. The sheet pressing portions 541 and 542 are provided so as to be swingable.

II. Second Embodiment The image forming apparatus 1 may include a paper discharge unit 371 shown in FIG. 4 instead of the paper discharge unit 37. FIG. 4 is a side view of the paper discharge unit 371. In the following, members having the same functions as those already described are given the same reference numerals and description thereof is omitted.

  As shown in FIG. 4, the paper discharge unit 371 includes two sheet pressing members 531 and 532 instead of the sheet pressing member 53. The sheet pressing members 531 and 532 are provided at substantially the same position in the discharge direction 101 by the substantially same arrangement method as the sheet pressing member 53. That is, the sheet pressing members 531 and 532 are members that are long in one direction. A first end 581 in the longitudinal direction of the sheet pressing member 531 and a first end 582 in the longitudinal direction of the sheet pressing member 532 are a shaft (not shown) arranged in the casing 31 in parallel in the front-rear direction in the same manner as the shaft 55. ). The second ends 591 and 592 of the sheet pressing members 531 and 532 are swingable free ends. The free end of the sheet pressing member 531 is a sheet pressing portion 543, and the free end of the sheet pressing member 532 is a sheet pressing portion 544.

  However, the sheet pressing members 531 and 532 are respectively disposed before and after the convex portion 52 in the front-rear direction. That is, the sheet pressing portions 543 and 544 are disposed so as to press the sheet 7 in the front-rear direction of the convex portion 52.

  Therefore, also in the present embodiment, the sheet 7 is held in the convex shape by the convex portion 52 and the sheet pressing portions 543 and 544 in the front-rear direction, that is, the central portion in the width direction is high. As a result, the height of both ends of the sheet 7 in the width direction is suppressed, and the next sheet 7 is smoothly discharged from the sheet discharge port 39.

  Two or more sheet pressing members may be provided, and one sheet pressing member may have two or more sheet pressing portions.

III. Third Embodiment The image forming apparatus 1 may include a paper discharge unit 372 shown in FIG. FIG. 5 is a side view of the paper discharge unit 372. In the following, members having the same functions as those already described are given the same reference numerals and description thereof is omitted.

  As illustrated in FIG. 5, the paper discharge unit 372 includes a convex portion 521 on the sheet receiving portion 511 instead of the convex portion 52. The convex part 521 has the same configuration as the convex part 52 in the shape, the arrangement position, the number of arrangements, etc., except that the cross section perpendicular to the left-right direction is rectangular. The convex portion 521 can also be referred to as a “rib”.

  As illustrated in FIG. 5, the paper discharge unit 372 includes a sheet pressing member 533 instead of the sheet pressing member 53. The sheet pressing member 533 has the same configuration as the sheet pressing member 53 except that the shape of the second end is different. That is, the sheet pressing member 533 is provided at the same position by the same arrangement method as the sheet pressing member 53. The sheet pressing member 533 is a member that is long in one direction. Further, the first end 583 in the longitudinal direction of the sheet pressing member 533 is held by a shaft (not shown) disposed in parallel with the front-rear direction in the housing 31 similarly to the shaft 55. The second end 593 of the sheet pressing member 533 is a swingable free end.

  However, the second end 59 of the sheet pressing member 53 of the first embodiment includes a concave portion 57 that is recessed in an isosceles triangle shape, whereas the second end 593 of the sheet pressing member 533 is recessed in a rectangular shape. A recess 571 is provided. That is, sheet pressing portions 545 and 546 are provided at the second end 593 of the sheet pressing member 533 so as to sandwich the concave portion 571 in the front-rear direction.

  Therefore, also in the present embodiment, the sheet 7 is held in a convex shape with a high central portion in the front-rear direction, that is, in the width direction, by the convex portion 521 and the sheet pressing portions 545 and 546. As a result, the height of both ends of the sheet 7 in the width direction is suppressed, and the next sheet 7 is smoothly discharged from the sheet discharge port 39.

  Note that the first embodiment and the third embodiment may be combined. In other words, the sheet pressing member 53 and the sheet pressing member 533 are interchangeable.

IV. Other Embodiments The convex portions (52 and 521) on the sheet receiving portion 51 described above can be changed to convex portions having other shapes as long as the paper 7 can prevent the paper discharge port 39. For example, two or more convex portions may be provided on the sheet receiving portion 51 in the left-right direction and / or the front-rear direction. Further, the convex portion need not be provided from the right end to the left end of the sheet receiving portion 51, and the convex portion may be provided only on a part of the sheet receiving portion 51 in the left-right direction. However, the convex portion is provided in the vicinity of the right end of the sheet receiving portion 51, so that it is possible to cope with papers of different sizes, and the curling of the paper in the vicinity of the paper discharge port 39 is suppressed, thereby discharging the subsequent paper Can be performed more smoothly.

  Moreover, although the above-mentioned effect is acquired because the convex part on the sheet | seat receiving part 51 is located in the width direction center or the center vicinity of the sheet | seat receiving part 51, this invention is not limited to this. .

  In the above, an apparatus adopting an electrophotographic method is exemplified as an image forming apparatus, but all the above-described paper discharge units can be applied to an ink jet image forming apparatus.

  In both the ink jet image forming apparatus and the electrophotographic image forming apparatus, there arises a problem of paper curling after printing. In inkjet image formation, the paper may be curled when the ink is dried. In electrophotographic image formation, when toner is fixed on a sheet with heat and pressure, the water contained in the sheet evaporates, and the sheet may be curled.

  The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the invention. In particular, a plurality of embodiments described in the present specification can be arbitrarily combined as necessary.

  The present invention can be used as a paper discharge unit of an image forming apparatus such as a copier, a printer, or a facsimile machine.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Image reading apparatus 3 Image forming apparatus main body 7 Paper 21 Image reading part 22 Document cover 23 Light source 24 Reflector 25 Scanner unit 26 Platen glass 31 Case 32 Image forming part 33 Fixing apparatus 34 Paper conveyance part 35 Paper feed Cassette 36 Manual feed tray 37 Paper discharge part 39 Paper discharge port 40 Photosensitive drum 41 Charger 42 Exposure head 43 Developer 44 Transfer roller 45 Cleaning roller 51 Sheet receiving part 52 Convex part 53 Sheet pressing member 55 Shaft 57 Concave 61 Heating Roller 63 Pressure roller 65 Nip part 101 Discharge direction 311 Opening part 371 Paper discharge part 372 Paper discharge part 511 Sheet receiving part 521 Protruding part 531 Sheet pressing member 532 Sheet pressing member 533 Sheet pressing member 541 Sheet pressing part 542 Sheet pressing part 5 3 sheet pressing portion 544 sheet pressing portion 545 sheet pressing portion 546 sheet pressing portion 571 recess

Claims (7)

A sheet receiving mechanism provided for a device for discharging a sheet,
A sheet receiver on which the discharged sheets are stacked;
A convex portion provided in the sheet receiving portion and protruding in the thickness direction of the sheet;
A sheet pressing portion that presses the sheet toward the sheet receiving portion in at least two places sandwiching the convex portion in a first direction intersecting the sheet discharge direction, and the sheet pressing portion swings in the sheet thickness direction; A sheet pressing member provided in a possible manner;
A sheet receiving mechanism comprising: The sheet pressing member is provided such that the second end is rotatable around the first end,
The sheet receiving mechanism according to claim 1, wherein the sheet pressing portion is provided at the second end. The sheet receiving mechanism according to claim 1, wherein the convex portion is provided at a central portion of the sheet receiving portion in the first direction. The sheet receiving mechanism according to claim 1, wherein two or more sheet pressing portions are provided on one sheet pressing member. The sheet receiving mechanism according to any one of claims 1 to 4, further comprising two or more sheet pressing members. The sheet receiving mechanism according to any one of claims 1 to 5, wherein the sheet pressing member is disposed closer to an upstream end of the sheet discharging direction with respect to the sheet receiving portion. A housing having a paper discharge port for discharging the sheet;
An image forming unit disposed in the housing and forming an image on a sheet;
A sheet conveying unit that discharges the sheet after the image is formed to the outside of the housing through the discharge port;
A sheet receiving unit disposed downstream of the sheet discharge port in the sheet discharge direction by the sheet conveying unit and on which the discharged sheets are stacked;
A convex portion provided in the sheet receiving portion and protruding in the thickness direction of the sheet;
A sheet pressing portion that presses the sheet toward the sheet receiving portion in at least two places sandwiching the convex portion in a first direction intersecting the sheet discharge direction, and the sheet pressing portion swings in the sheet thickness direction; A sheet pressing member provided in a possible manner;
An image forming apparatus comprising:

Images