JP2019163159A - Sheet ejection device and image processing device - Google Patents

Abstract

To provide a sheet ejection device with a curl correction function, which reduces occurrence of sheet collision noise.SOLUTION: An image formation device includes: a drive roller 82 that ejects a sheet S in a housing 2; a first pinch roller 83 that is provided in a position facing the drive roller 82 and contacts the drive roller 82 and rotates; a second pinch roller 84 that contacts the drive roller 82 and rotates in the downstream in the ejection direction from the first pinch roller 83; a holder 85 that connects the first pinch roller 83 and the second pinch roller 84 and holds the pinch roller 83 movable between the contact position where the first pinch roller 83 contacts the drive roller 82 and the separate position where they separate; energizing means 86 that energizes the first pinch roller 83 toward the drive roller 82; a guide member 87 that is positioned below an upper end of the holder 85 when the first pinch roller 83 is positioned at the contact position and is positioned above the upper end of the holder 85 when it is positioned at the separate position against the energizing means 86.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a sheet discharging apparatus having a curl correction function.

  2. Description of the Related Art Conventionally, a sheet discharge device has a conveyance function and a curl correction function in the vicinity of a discharge port in order to correct a sheet curl generated during image processing such as image formation and during conveyance along a conveyance path and discharge it to a tray. There may be provided a roller having a roller and a roller.

  For example, in Patent Document 1, one roller is arranged on the upper side, two rollers arranged in the sheet conveying direction held by the holder on the lower side, and pressed by a leaf spring from the lower side of the holder to the lower side A configuration is disclosed in which the two rollers are rotated in contact with the upper roller. According to this configuration, the sheet is pressed along the peripheral surface of the upper roller by the two lower rollers to correct the curl.

JP 2000-56530 A

  In the case of the configuration of Patent Document 1, since the sheet has a shape along the upper roller between the two lower rollers, the sheet is curved along the conveyance direction. Therefore, the rear end portion of the conveyed sheet may jump to the holder side between the two lower rollers immediately after passing the first lower roller. For example, when transporting a stiff sheet such as cardboard, the rear end of the sheet jumps to the holder side and collides with a member arranged on the upper part of the holder or around the holder to generate a collision sound. Alternatively, the conveyance of the sheet may be disturbed due to the trailing edge of the sheet.

  It is an object of the present application to provide a technique for reducing the jumping of the trailing edge of a sheet in a sheet discharging apparatus having a curl correction function.

  The sheet discharge device of the present invention includes a housing, a drive roller that discharges the sheet along the discharge direction in the housing, and a first pinch roller that is disposed at a position facing the drive roller and rotates in contact with the drive roller. And a second pinch roller that is disposed at a position facing the drive roller downstream of the first pinch roller and rotates in contact with the drive roller, and connects the first pinch roller and the second pinch roller. A holder having a connecting portion to hold, wherein the first pinch roller is movably held between a contact position where the first pinch roller contacts the driving roller and a spaced position where the first pinch roller is separated from the driving roller. Holder, an urging means for urging the first pinch roller toward the drive roller, and a position from the first pinch roller to the second pinch roller in the discharge direction. The predetermined position is a position away from the drive roller than the connecting portion of the holder when the first pinch roller is located at the contact position, and the first pinch roller is the biasing means. And a guide member that is closer to the drive roller than the connecting portion of the holder when positioned at the separated position.

  According to the above configuration, the first pinch roller is separated from the driving roller by the waist of the conveyed sheet, and the sheet is conveyed along the separated first pinch roller or guide member.

  According to the present invention, when the first pinch roller is pushed by the sheet and separated from the driving roller, the rear end portion of the sheet is conveyed from the separated first pinch roller to the guide member. Splashing is reduced.

1 is a central sectional view of an image forming apparatus according to an embodiment. FIG. 3 is a perspective view around a discharge unit of the image forming apparatus. It is AA sectional drawing of FIG. It is a perspective view of the lower part of a discharge mechanism. It is a figure which shows the state which the 1st pinch roller displaced to the separation position in FIG. It is sectional drawing of the discharge mechanism in conveyance of the sheet | seat with weak waist. It is sectional drawing of the discharge mechanism in conveyance of the sheet | seat with weak waist. It is sectional drawing of the discharge mechanism in conveyance of the sheet | seat with which a waist is strong. It is sectional drawing of the discharge mechanism in conveyance of the sheet | seat with which a waist is strong. FIG. 10 is a simplified diagram illustrating conveyance of a low-waist sheet. FIG. 6 is a simplified diagram illustrating conveyance of a stiff sheet with a guide member in a horizontal state. FIG. 6 is a simplified diagram illustrating conveyance of a stiff sheet with a guide member in a horizontal state. FIG. 6 is a simplified diagram illustrating conveyance of a stiff sheet with a guide member tilted. FIG. 10 is a simplified diagram in which a first pinch roller and a second pinch roller in another embodiment move integrally.

  In the following description, as shown in FIG. 1 and FIG. 2, the image forming apparatus 1 is installed so that it can be used as a reference, the side from which the sheet tray 10 is pulled out is the front, and the opposite side is the rear. The left and right directions are defined when 1 is viewed from the front side, and each direction is defined with the discharge tray 2B side of the image forming apparatus 1 being up and the opposite being down.

[Entire configuration of image forming apparatus]
An image forming apparatus 1 shown in FIG. 1 is an embodiment of an image processing apparatus according to the present invention, and includes a housing 2, a supply unit 3, a motor 4, and an image forming unit 5 as an example of an image processing unit. And a discharge unit 8 as an example of a sheet discharge device.

  The supply unit 3 is disposed below the image forming apparatus 1 and conveys the sheet S held by the supply unit 3 to the image forming unit 5. The image forming unit 5 is disposed downstream of the supply unit 3 in the conveyance direction of the sheet S, and forms an image on the sheet S conveyed from the supply unit 3. The discharge unit 8 is disposed downstream of the image forming unit 5 in the conveyance direction of the sheet S, and discharges the sheet S on which an image has been formed by the image forming unit 5 to the outside of the image forming apparatus 1.

  The supply unit 3 includes a sheet tray 10, a paper feed mechanism 20, a transport roller 24, and a registration roller 26.

  The sheet tray 10 is detachably mounted on a sheet tray mounting portion 2A formed at the lower part of the housing 2. The sheet tray 10 is mounted on the sheet tray mounting portion 2A by being inserted from the front to the rear with respect to the sheet tray mounting portion 2A, and is positioned at the mounting position. Further, the sheet tray 10 is positioned from the mounting position to the pulling position by being pulled out from the rear to the front with respect to the sheet tray mounting portion 2A.

  The sheet tray 10 includes a tray main body 11 capable of supporting a plurality of sheets S, a pressure plate 12 disposed on the tray main body 11 so that the sheets S can be stacked and displaced in the vertical direction, and the pressure plate 12. And a pressure plate raising member 13 for raising the pressure.

  The front end portion of the pressure plate 12 is displaced in the vertical direction around the rotation fulcrum 12A. The pressure plate raising member 13 is driven by the motor 4 to raise the tip of the pressure plate 12. As the pressure plate raising member 13 is raised, the pressure plate 12 is lifted, and the sheets S stacked on the pressure plate 12 are raised to a paper feedable position as shown in FIG.

  The sheet feeding mechanism 20 separates and takes out the sheets S stacked on the sheet tray 10 one by one, and conveys the sheets S toward the conveying roller 24. The paper feed mechanism 20 includes a pickup roller 21, a separation roller 22, and a separation pad 23.

  The pickup roller 21 is a roller for taking out the sheet S that has been raised to the paper feedable position by the pressure plate 12, and is disposed above the pressure plate 12. The separation roller 22 is disposed downstream of the pickup roller 21 in the sheet S conveyance direction, and the separation pad 23 is disposed opposite to the separation roller 22 and is urged toward the separation roller 22.

  The sheet S taken out by the pickup roller 21 is sent to the separation roller 22 side, separated one by one between the separation roller 22 and the separation pad 23, and conveyed toward the conveyance roller 24.

  The conveyance roller 24 is a roller that applies a conveyance force to the sheet S, and is disposed downstream of the sheet feeding mechanism 20 in the conveyance direction of the sheet S. The sheet S conveyed from the sheet feeding mechanism 20 toward the conveyance roller 24 is conveyed toward the registration roller 26.

  The registration roller 26 is disposed on the downstream side of the conveyance roller 24 in the conveyance direction of the sheet S. The registration roller 26 restricts the movement of the leading edge of the conveyed sheet S and temporarily stops it, and then conveys it toward the transfer position at a predetermined timing.

  The image forming unit 5 includes a process cartridge 50 that transfers an image onto the surface of the sheet S conveyed from the supply unit 3, an exposure unit 60 that exposes the surface of the photosensitive drum 54 of the process cartridge 50, and the process cartridge 50. And a fixing unit 70 for fixing the image transferred to the sheet S.

  The process cartridge 50 is disposed above the sheet tray mounting portion 2 </ b> A in the housing 2. The process cartridge 50 includes a developer storage chamber 51, a supply roller 52, a development roller 53, a photosensitive drum 54, and a transfer roller 55.

  The developer storage chamber 51 stores toner that serves as a developer. The toner stored in the developer storage chamber 51 is sent to the supply roller 52 while being stirred by a stirring member (not shown). The supply roller 52 further supplies the toner sent from the developer storage chamber 51 to the development roller 53.

  The developing roller 53 is disposed in close contact with the supply roller 52 and carries the toner supplied from the supply roller 52. Further, a developing bias is applied to the developing roller 53 by a bias applying means (not shown).

  The photosensitive drum 54 is disposed adjacent to the developing roller 53. The surface of the photosensitive drum 54 is uniformly charged by a charger (not shown) and then exposed by the exposure unit 60. The exposed portion of the photosensitive drum 54 has a lower potential than the other portions, and an electrostatic latent image based on image data is formed on the photosensitive drum 54. Then, charged toner is supplied from the developing roller 53 to the surface of the photosensitive drum 54 on which the electrostatic latent image is formed, whereby the electrostatic latent image is visualized and becomes a developer image.

  The transfer roller 55 is disposed to face the photosensitive drum 54, and a negative transfer bias is applied to the transfer roller 55 by a bias applying unit (not shown). In a state where a transfer bias is applied to the surface of the transfer roller 55, the sheet S is conveyed while being nipped between the photosensitive drum 54 on which the developer image is formed and the transfer roller 55 (transfer position). The developer image formed on the surface of the photosensitive drum 54 is transferred to the surface of the sheet S.

  The exposure unit 60 includes a laser diode, a polygon mirror, a lens, and a reflecting mirror, and irradiates laser light toward the photosensitive drum 54 based on image data input to the image forming apparatus 1. Thus, the surface of the photosensitive drum 54 is exposed.

  The fixing unit 70 includes a heating roller 71 and a pressing roller 72. The heating roller 71 is rotationally driven by the driving force from the motor 4, and the heating roller 71 is heated by supplying electric power from a power source (not shown). The pressing roller 72 is disposed so as to face the heating roller 71, and is in close contact with the heating roller 71 and is driven to rotate. When the sheet S on which the developer image has been transferred is conveyed to the fixing unit 70, the fixing unit 70 conveys the sheet S while sandwiching it between the heating roller 71 and the pressing roller 72, and the developer is transferred to the sheet S. Fix the image. The sheet S to be fixed may be curved and curled so that the surface heated by the heating roller 71, the upper surface in FIG.

  The discharge unit 8 includes a discharge mechanism 81 and a discharge port 8A, and discharges the sheet S conveyed from the fixing unit 70 toward the outside of the housing 2. A discharge tray 2B is formed on the upper surface of the housing 2, and the sheet S discharged to the outside of the housing 2 is deposited on the discharge tray 2B. Hereinafter, the discharge unit 8 will be described in detail.

[Discharge unit]
FIG. 2 is a perspective view around the discharge unit 8 of the image forming apparatus 1. 3 is a cross-sectional view taken along the line AA in FIG. FIG. 4 is a perspective view of the lower portion of the discharge mechanism 81, (a) is a front perspective view, and (b) is a rear perspective view. FIG. 5 is a view showing a state in which the first pinch roller 83 is displaced to the separation position in FIG.

  The discharge mechanism 81 discharges the sheet S conveyed from the fixing unit 70 to the discharge tray 2B through the discharge port 8A. The discharge mechanism 81 includes four sets of a drive roller 82, a first pinch roller 83, a second pinch roller 84, a holder 85, a biasing means 86, and a guide member 87 in the left-right direction. As indicated by a two-dot chain line in FIG. 1, the conveyance path P from the fixing unit 70 to the discharge mechanism 81 extends from the fixing unit 70 to the rear side, then extends upward, and further, the discharge mechanism 81. It curves so as to extend forward. Due to the curved shape of the conveyance path P downstream of the fixing unit 71 in the discharge direction, the conveyed sheet S may be curved and curled so that the front surface of the sheet S is concave.

  As shown in FIG. 3, the drive roller 82 is disposed in the vicinity of the discharge port 8 </ b> A of the housing 2 and above the conveyance path P. A driving force from the motor 4 is transmitted to the driving roller 82. The driving roller 82 is in contact with the first pinch roller 83 and the second pinch roller 84 to form a nip, thereby conveying the sheet S conveyed along the conveyance path P along the discharge direction. In the present embodiment, the diameter of the first pinch roller 83 is set to be smaller than the diameter of the driving roller 82 and the diameter of the second pinch roller 84.

  The first pinch roller 83 is disposed near the discharge port 8 </ b> A of the housing 2 and below the driving roller 82, and is disposed at a position facing the driving roller 82. The shaft portion 83 </ b> A of the first pinch roller 83 is rotatably supported by the holder 85. The first pinch roller 83 rotates following the drive roller 82 by forming a nip by contacting the drive roller 82.

  The second pinch roller 84 is disposed near the discharge port 8 </ b> A of the housing 2 and below the driving roller 82, and is disposed at a position facing the driving roller 82. The second pinch roller 84 is disposed downstream of the first pinch roller 83 in the discharge direction. The shaft portion 84A of the second pinch roller 84 is rotatably supported by the housing 2 around the first axis R1. The second pinch roller 84 rotates by being driven by the drive roller 82 by forming a nip by contacting the drive roller 82.

  The first pinch roller 83 and the second pinch roller 84 form a nip with respect to the drive roller 82, so that the sheet S follows the peripheral surface of the drive roller 82 by the first pinch roller 83 and the second pinch roller 84. It is conveyed while being pressed. Thereby, the curl of the sheet S is corrected.

  As shown in FIG. 4, the holder 85 includes a substantially rectangular plate-like lower side portion 85A, a plate-like left side portion 85B extending upward at a right angle from the left end portion of the lower side portion 85A, and the right end of the lower side portion 85A. It has a plate-like right side portion 85C extending upward from the portion at right angles and four guide ribs 85D extending upward from the lower side portion 85A at right angles.

  The left side portion 85B and the right side portion 85C have a hole portion 85E through which the shaft portion 84A of the second pinch roller 84 is inserted. By inserting the shaft portion 84A through the hole 85E, the holder 85 is supported by the shaft portion 84A of the second pinch roller 84 so as to be rotatable about the first axis R1. Further, the left side portion 85B and the right side portion 85C have a hole portion 85F through which the shaft portion 83A of the first pinch roller 83 is inserted. The holder 83 supports the first pinch roller 83 to be rotatable by inserting the shaft portion 83A into the hole portion 85F.

  The left part 85B and the right part 85C have a symmetrical shape. The upper end portion 85H, which is the end portion on the drive roller 82 side of the left side portion 85B, and the upper end portion 85G, which is the end portion on the drive roller 82 side of the right side portion 85C, have a role of guiding the leading end portion of the sheet S. The upper end portion 85H is located between the first pinch roller 83 and the second pinch roller 84 when viewed from the axial direction of the shaft portion 84A, and has a shape recessed downward. Similarly to the upper end portion 85H, the upper end portion 85G is located between the first pinch roller 83 and the second pinch roller 84 when viewed from the axial direction of the shaft portion 84A, and is recessed downward. It has a shape.

  The guide rib 85D is disposed upstream of the first pinch roller 83 in the discharge direction, and is formed at the same height as the upstream upper end of the left side 85B and the upstream upper end of the right 85C. The guide rib 85D guides the leading end of the sheet S to the nip position between the first pinch roller 83 and the driving roller 82 in cooperation with the upstream upper end of the left portion 85B and the upstream upper end of the right portion 85C.

  The holder 85 connects the first pinch roller 83 and the second pinch roller 84, and swings about the first axis R1. As the holder 85 swings, the first pinch roller 83 moves between a contact position (position in FIG. 3) that contacts the driving roller 82 and a separation position (position in FIG. 5) that is separated from the driving roller 82. It is movable.

  As shown in FIG. 3, the urging means 86 is a member that urges the first pinch roller 83 in the direction toward the driving roller 82, that is, in the direction from the separated position toward the contact position. As the urging means 86, an elastic body such as a spring or rubber can be used, and in this embodiment, a compression coil spring is used. Specifically, the urging means 86 is disposed between the lower portion 85A of the holder 85 and the housing 2, and urges the lower portion 85A of the holder 85 upward. Accordingly, the first pinch roller 83 is located at the contact position in a state where the sheet S is not being conveyed, and is moved downward to the separation position by being pushed downward by the strength of the waist of the sheet S.

  As shown in FIG. 2, the guide members 87 are disposed on both sides of the first pinch roller 83 in the axial direction (left-right direction) of the shaft portion 83 </ b> A of the first pinch roller 83. The guide member 87 is a member that guides the sheet S when the first pinch roller 83 moves to the separation position against the biasing means 86. The guide member 87 in the present embodiment is a rib formed on the housing 2 so as to constitute the lower part of the transport path P near the discharge port 8A.

  As shown in FIG. 3, the guide member 87 includes a first guide portion 87A, a second guide portion 87B, and a third guide portion 87C.

  The first guide portion 87A is formed at a position between the first pinch roller 83 and the second pinch roller 84 in the transport direction, and is away from the drive roller 82 from the first pinch roller 83 toward the second pinch roller 84. Inclined to. When viewed from the left-right direction in FIG. 3, the first guide portion 87 </ b> A in this embodiment is located between the circular arrangement area of the first pinch roller 83 and the circular arrangement area of the second pinch roller 84, and both circular arrangement areas. It is located in a region that partially overlaps the region, and is formed so as to be inclined downward toward the front. That is, the first guide portion 87A has a circular shape of the second pinch roller 84 from the circular arrangement region of the first pinch roller 83 when viewed from the axial direction (left-right direction) of the first pinch roller 83 and the second pinch roller 84. It is arranged in an area that partially overlaps the area up to the arrangement area.

  The second guide portion 87B is located on the upstream side in the discharge direction of the first guide portion 87A, and is curved so as to be convex toward the transport space of the transport path P. The second guide portion 87B in the present embodiment is located on the upstream side in the discharge direction of the first pinch roller 83 and is formed in an arc shape that is convex toward the transport space of the transport path P.

  The third guide portion 87C is located upstream of the second guide portion 87B in the discharge direction, and is formed so as to be inclined in a direction approaching the drive roller 82 from the discharge direction upstream side to the downstream side. The third guide portion 87C in the present embodiment is located upstream in the discharge direction of the second guide portion 87B, and inclines upward from the rear toward the second guide portion 87B in order to narrow the transport space of the transport path P. Is formed.

  Next, the positional relationship between the guide member 87 and the first pinch roller 83 in the height direction will be described. As shown in FIG. 3, when the first pinch roller 83 is in the contact position, the first pinch roller 83 protrudes upward from the guide member 87. That is, in the present embodiment, the upper end portion of the first pinch roller 83 at the contact position protrudes above the upper end portion of the first guide portion 87A.

  On the other hand, as shown in FIG. 5, when the first pinch roller 83 is in the separated position, the upper end portion of the first pinch roller 83 is at the same position as the guide member 87 in the vertical direction. That is, in the present embodiment, the upper end portion of the first pinch roller 83 in the separated position is the same height as the upper end portion of the first guide portion 87A. Accordingly, the sheet S is conveyed along the upper end portion of the first pinch roller 83 and the upper end portion of the first guide portion 87A that are at the same height.

  Next, the positional relationship in the height direction between the guide member 87 and the holder 85 will be described. As shown in FIG. 3, when the first pinch roller 83 is in the contact position, the upper end portions 85 </ b> G and 85 </ b> H of the holder 85 are located above the guide member 87. That is, in this embodiment, when the 1st pinch roller 83 exists in a contact position, the upper end parts 85G and 85H of the holder 85 are located above the upper end part of 1st guide part 87A.

On the other hand, as shown in FIG. 5, when the first pinch roller 83 is in the separated position, the upper end portions 85 </ b> G and 85 </ b> H of the holder 85 are located below the guide member 87. That is, in the present embodiment, when the first pinch roller 83 is in the separated position, the upper end portions 85G and 85H of the holder 85 are positioned below the upper end portion of the first guide portion 87A.

  When the first pinch roller 83 is in the separated position, the upper end portions 85G and 85H of the holder 85 are in relation to the intersection N between the nip line L between the drive roller 82 and the second pinch roller 84 and the first guide portion 87A. And located on the opposite side of the drive roller 82. That is, in the present embodiment, when the first pinch roller 83 is in the separated position, the upper end portions 85G and 85H of the holder 85 are located below the intersection N. Accordingly, the sheet S is guided by the first guide portion 87A without contacting the upper end portions 85G and 85H.

  Next, an operation in which the discharge mechanism 81 conveys the sheet S will be described. 6 and 7 are cross-sectional views of the discharge mechanism 81 that is conveying the sheet S having a low waist. 8 and 9 are cross-sectional views of the discharge mechanism 81 that is conveying the stiff sheet S. FIG. FIG. 6 is a view in the middle of the sheet S passing through the driving roller 82, the first pinch roller 83, and the second pinch roller 84. FIG. 7 shows a state immediately after the rear end portion of the sheet S passes through the nip position between the driving roller 82 and the first pinch roller 83.

  In the present embodiment, the curl formed at the time of image formation and the sheet conveyance in the conveyance path P close to the discharge mechanism 81 has a convex shape upward in the conveyance direction of the discharge mechanism 81. 81 curls so as to be convex downward in the transport direction.

  The thin sheet S such as thin paper is conveyed along the conveyance path P to the nip position between the driving roller 82 and the first pinch roller 83, and then along the circumferential surface of the driving roller 82 and the second roller S 2. It is conveyed to the nip position with the pinch roller 84 and discharged from the discharge port 8A. Note that the leading end of the sheet S is conveyed while being guided by the upper end portions 85G and 85H when moving from the first pinch roller 83 to the second pinch roller 84.

  When transporting a sheet S having a low stiffness, such as thin paper, the force by which the sheet S pushes the first pinch roller 83 downward is weaker than the biasing force of the biasing means 86, and therefore the first pinch roller 83 moves from the contact position. do not do. Therefore, the sheet S protrudes downward along the peripheral surface of the drive roller 82 from the nip position between the drive roller 82 and the first pinch roller 83 to the nip position between the drive roller 82 and the second pinch roller 84. By being conveyed in a curved state, the upward curling is strongly corrected.

  As shown in FIG. 7, the rear end portion of the sheet S passes through the nip position between the driving roller 82 and the first pinch roller 83. At this time, the rear end portion of the sheet S jumps downward from the driving roller 82 and collides with the upper end portions 85G and 85H of the holder 85. However, since the waist of the sheet S is weak, the collision sound of the rear end portion of the sheet S is It doesn't grow up. In the case of a sheet S having a low stiffness such as thin paper, the curl formed during sheet conveyance and image formation tends to be large, and the discharge mechanism 81 needs to strongly correct the curl. For a sheet S having a low stiffness such as thin paper, the curl can be strongly corrected by the first pinch roller 83 not moving from the contact position.

  Next, the stiff sheet S such as cardboard will be described. FIG. 8 is a view in the middle of the sheet S passing through the driving roller 82, the first pinch roller 83, and the second pinch roller 84, and FIG. 9 shows the rear end portion of the sheet S on the first pinch roller 83. It shows a certain state. A stiff sheet S such as thick paper is conveyed along the conveyance path P to the nip position between the drive roller 82 and the first pinch roller 83. Subsequently, the sheet S is conveyed to the nip position between the driving roller 82 and the second pinch roller 84 and discharged from the discharge port 8A, and pushes down the first pinch roller 83 to the separation position. Note that the leading end of the sheet S is conveyed while being guided by the upper end portions 85G and 85H when moving from the first pinch roller 83 to the second pinch roller 84.

  When transporting a stiff sheet S such as thick paper, the force by which the sheet S pushes the first pinch roller 83 downward is stronger than the biasing force of the biasing means 86, so the first pinch roller 83 moves to the separated position. To do. Accordingly, the rear end portion of the sheet S is conveyed along the first guide portion 87A from the position in contact with the first pinch roller 83 and the first guide portion 87A to the nip position between the drive roller 82 and the second pinch roller 84. Is done. Thereby, since the rear end portion of the sheet S is conveyed without splashing, the collision sound is reduced. In the case of a strong sheet S such as thick paper, the curl formed during sheet conveyance and image formation tends to be small, and the discharge mechanism 81 does not need to strongly correct the curl. As for the stiff sheet S such as thick paper, the collision noise can be reduced without much curl correction by moving the first pinch roller 83 to the separated position.

  Next, the basic operation of this embodiment will be described. 10 to 14 will be described using simplified diagrams for easy understanding. FIG. 10 is a diagram illustrating conveyance of a sheet S having a low stiffness such as thin paper, and FIGS. 11 to 13 are diagrams illustrating conveyance of a sheet S having a low stiffness such as thick paper. 10-12 is a figure explaining the state by which the 1st guide part 87A was arrange | positioned horizontally, and FIG. 13 is a figure which shows the state by which the 1st guide part 87A was inclined and arrange | positioned. 11 to 13 show a state in which the first pinch roller 83 is separated from the driving roller 82 by the waist of thick paper or the like. Further, for convenience of explanation, it is assumed that the waists of the cardboard and the like are all the same, and the amount of the first pinch roller 83 spaced apart by the waist of the cardboard or the like is constant.

  FIG. 10A is a diagram illustrating a state where the first guide portion 87A is not provided as a comparative example. FIG. 10A shows a state in which the sheet S is not conveyed, and the first pinch roller 83 and the second pinch roller 84 are in contact with the drive roller 82. The nip position between the first pinch roller 83 and the driving roller 82 is N1, and the nip position between the second pinch roller 84 and the driving roller 82 is N2. When viewed from the axial direction of both pinch rollers 83 and 84, the intersection of the upper end portion 85G of the holder 85 and the outer peripheral surface of the first pinch roller 83 is C1, and the upper end portion 85G of the holder 85 and the second pinch roller An intersection point of the outer peripheral surface 84 is denoted by D1, and a line connecting the intersection point C1 and the intersection point D1 is denoted by a broken line H2. The highest upper end portion on the outer peripheral surface of the first pinch roller 83 is A1, and a line perpendicular to the line connecting the upper end portion A1 and the shaft portion 83A is a vertical line H1.

  FIG. 10B is a diagram illustrating a configuration in which the first guide portion 87A is provided in FIG. 10A, and is a diagram illustrating a state in which a weak sheet S such as thin paper is being conveyed. An upper end portion 87A1 (corresponding to a sheet contact portion described in claims) of the first guide portion 87A is disposed between the first pinch roller 83 and the second pinch roller in the discharge direction, and is a connecting portion of the holder 85. It is arranged at a position farther from the drive roller 82 than. That is, the upper end portion 87A1 of the first guide portion 87A is positioned below the upper end portion 85G of the holder 85, and is positioned horizontally with respect to the broken line H2. FIG. 10B is a diagram in the middle of conveyance of the sheet S, and shows a state in which the rear end portion of the sheet S is in contact with the upper end portion A <b> 1 of the first pinch roller 83. FIG. 10C shows a state immediately after the trailing edge of the sheet S has passed through the nip position N1 between the first pinch roller 83 and the driving roller 82.

  When the sheet S is conveyed, since the waist of the sheet S is weak, the first pinch roller 83 does not move to the separation position and the state of the contact position is maintained. Therefore, when the sheet S is conveyed, first, the leading end of the sheet S passes through the nip position N1 and is conveyed downstream in the discharge direction by the driving roller 82 and the first pinch roller 83. Thereafter, the leading end portion of the sheet S abuts on the upper end portion 85G of the holder 85, passes through the nip position N2, and is conveyed downstream in the discharge direction by the driving roller 82 and the second pinch roller 84.

  As shown in FIG. 10C, the rear end portion of the sheet S comes into contact with the upper end portion 85G of the holder 85 immediately after passing the nip position N1. There is a step in the vertical direction between the vertical line H1 that is the position of the upper end A1 of the first pinch roller 83 and the broken line H2 that is the position of the upper end 85G of the holder 85, but the waist of the sheet S is weak. The collision sound in which the rear end portion of the sheet S collides with the upper end portion 85G of the holder 85 is small.

  Next, conveyance of a stiff sheet S such as thick paper will be described. FIG. 11A is a diagram illustrating a state where the first guide part 87A is not provided as a comparative example, and FIGS. 11B and 11C are states where the first guide part 87A is provided. FIG.

  In FIG. 11A, the rear end portion of the sheet S, which is strong, such as thick paper, is in contact with the upper end portion A2 of the first pinch roller 83, and the first pinch roller 83 is driven by the waist of the sheet S. It is in the state separated from. The highest upper end portion on the outer peripheral surface of the first pinch roller 83 in the separated state is defined as A2, and a line perpendicular to the line connecting the upper end portion A2 and the shaft portion 83A and passing through the upper end portion A2 is defined. A vertical line H3 is assumed, and a distance from the upper end 85G of the holder 85 to the vertical line H3 is α1. The upper end portion A2 of the first pinch roller 83 is lowered from the position of the vertical line H1 at 10 (a) to the position of the upper end portion A2 in FIG. 11 (a). This lowering amount is defined as a separation amount H4. In this embodiment, when a stiff sheet S such as thick paper is conveyed, the first pinch roller 83 is moved downward by the separation amount H4. That is, the position where the upper end portion of the first pinch roller 83 can be separated from the driving roller 82 to the maximum is the position of the vertical line H3.

  FIG. 11B is a view in which the first guide portion 87A is provided in FIG. 11A, and the upper end portion 87A1 of the first guide portion 87A is located below the vertical line H3, and the first guide portion 87A is the first guide portion 87A. In this example, a part of the upper end portion 87A1 of the guide portion 87A is positioned above the upper end portion 85G of the holder 85. That is, the upper end portion 87A1 of the first guide portion 87A is disposed at a position closer to the drive roller 82 than the connection portion of the holder 85. Here, the distance from the vertical line H3 to the upper end portion 87A1 of the first guide portion 87A is α2.

  11A, when the sheet S such as thick paper is conveyed, the rear end portion of the sheet S first passes through the upper end portion A2 of the first pinch roller 83 and is further discharged from the upper end portion A2 of the first pinch roller 83. When positioned on the downstream side in the direction, it contacts the upper end 85G of the holder 85. At this time, since there is a step (α1) between the upper end portion 85G of the holder 85 and the vertical line H3, the rear end portion of the sheet falls from the upper end portion A2 of the first pinch roller 83, and the upper end portion of the holder 85 It collides with 85G and a collision sound is generated.

  When the sheet S is conveyed in FIG. 11B, the rear end portion of the sheet S passes through the upper end portion A2 of the first pinch roller 83, and further to the downstream side in the discharge direction from the upper end portion A2 of the first pinch roller 83. When positioned, it comes into contact with the upper end portion 87A1 of the first guide portion 87A. At this time, since there is a step (α2) between the upper end portion 87A1 of the first guide portion 87A and the vertical line H3, the rear end portion of the sheet falls from the upper end portion A2 of the first pinch roller 83 and the collision sound Will occur. However, when the first guide portion 87A is arranged, the level difference is small compared to the case where the first guide portion 87A is not arranged. That is, since the relationship between α1 and α2 is α1> α2, the collision noise is reduced when the guide member 87 is present as compared with the case where the guide member 87 is not present.

  FIG. 11C is an example in which the upper end portion 87A1 of the first guide portion 87A is disposed at the same position as the vertical line H3 in the vertical direction. The rear end of the sheet S in FIG. 11C passes through the upper end A2 of the first pinch roller 83 and is further conveyed downstream in the discharge direction from the upper end A2 of the first pinch roller 83. In addition, it is guided while coming into contact with the upper end portion 87A1 of the first guide portion 87A. Since there is no distance (step) between the upper end portion A2 of the first pinch roller 83 and the upper end portion 87A1 of the first guide portion 87A, the rear end portion of the sheet S is guided smoothly without jumping. Thereby, the rear end portion of the sheet S is reduced in the collision sound that collides with the upper end portion 85G of the holder 85 or the upper end portion 87A1 of the first guide portion 87A.

    FIG. 12A shows an example in which the upper end portion 87A1 of the first guide member 87A is located above the vertical line H3 and is located above the upper end portion 85G of the holder 85. Specifically, the upper end portion 87A1 of the first guide member 87A is disposed along the vertical line H5 between the broken line H2 and the vertical line H3 in the vertical direction.

    In FIG. 12 (a), A3 which is the highest upper end portion on the outer peripheral surface of the first pinch roller 83 is lowered from the position A1 in FIG. 10 (a) to the position A3 in FIG. 12 (a). Yes. This decrease amount is set as a separation amount H6. The maximum separation amount due to the waist of the sheet S such as cardboard is H4. Originally, the upper end portion A3 of the first pinch roller 83 can be moved to the position of the vertical line H3. In FIG. Since the upper end portion 87A1 of the portion 87A is located on the vertical line H5, the upper end portion 87A1 moves to the vertical line H5 that is above the vertical line H3. Since the separation amount H6 is smaller than the maximum separation amount H4, the rear end portion of the sheet S is also the upper end portion of the first guide portion 87A from the upper end portion A3 in FIG. It is guided smoothly along the part 87A1. Thereby, the collision sound of the rear end portion of the sheet S is reduced.

  Further, since the separation amount H6 of the first pinch roller 83 shown in FIG. 12A is smaller than the separation amount H4 shown in FIG. 11C, the first pinch roller 83 is driven when it returns from the separation position to the contact position. The collision sound that collides with the roller 82 can also be reduced.

  FIG. 12B is a diagram illustrating a range in which the upper end portion 87A1 of the first guide portion 87A is disposed. The upper end portion A2 of the first pinch roller 83 in FIG. 12B is in a state of being moved downward by the maximum separation amount H4 due to the waist of the sheet S such as cardboard, as in FIG. 11A.

  The range where the upper end portion 87A1 of the first guide portion 87A is disposed is the upper end portion A2, the intersection point C2, the intersection point D2, the intersection point D1, and the range J1 surrounded by the intersection point C1. The intersection point C1 indicates an intersection point between the upper end portion 85G of the holder 85 and the outer peripheral surface (arc surface) of the first pinch roller 83 in a state where the upper end portion A1 of the first pinch roller 83 is disposed at the position of the vertical line H1. ing. An intersection D1 indicates an intersection between the upper end portion 85G of the holder 85 and the outer peripheral surface of the second pinch roller 84 in a state where the upper end portion A1 of the first pinch roller 83 is disposed at the position of the vertical line H1. . A line connecting the intersection C1 and the intersection D1 is defined as a first line segment. Further, the intersection point C2 is an intersection point between the upper end portion 85G of the holder 85 and the outer peripheral surface (arc surface) of the first pinch roller 83 in a state where the upper end portion A2 of the first pinch roller 83 is disposed at the position of the vertical line H3. Is shown. Further, the intersection point D2 indicates an intersection point between the upper end portion 85G of the holder 85 and the outer peripheral surface of the second pinch roller 84 in a state where the upper end portion A2 of the first pinch roller 83 is disposed at the position of the vertical line H3. . A line connecting the intersection point C2 and the intersection point D2 is defined as a second line segment. A line connecting the upper end portion A <b> 2 and the intersection C <b> 2 is a line along the outer peripheral surface of the first pinch roller 83. A line connecting the intersection point C2 and the intersection point D2 is a line along the upper end portion 87A1 of the first guide portion 87A, and a line connecting the intersection point D2 and the intersection point D1 is a line along the outer peripheral surface of the second pinch roller 84. It is. A line connecting the intersection C1 and the upper end A2 of the first pinch roller 83 is defined as a third line segment.

  FIG. 13A is a diagram showing a state in which the upper end 87A1 of the first guide part 87A is inclined and the upper end 87A1 of the first guide 87A is positioned below the vertical line H3. Indicates the state. The first guide portion 87A upper end portion 87A1 is inclined downward from the first pinch roller 83 toward the second pinch roller 84. Here, the distance from the vertical line H3 to the upper end portion 87A1 of the first guide portion 87A is α3. Since there is a level difference α3 in FIG. 13A, a collision sound is generated as in FIG. However, when the first guide portion 87A is present, the level difference is smaller than when the first guide portion 87A is not present, and the collision noise is reduced.

  FIG. 13B shows a state where the upper end portion 87A1 of the first guide portion 87A is disposed at the same position as the upper end portion A2 of the first pinch roller 83. In FIG. 13B, similarly to FIG. 11C, the rear end portion of the sheet S is smoothly guided while coming into contact with the upper end portion 87A1 of the first guide portion 87A. Since there is no distance (step) between the upper end portion A2 of the first pinch roller 83 and the upper end portion 87A1 of the first guide portion 87A, the rear end portion of the sheet S is guided smoothly without jumping. Thereby, the collision sound which the rear-end part of the sheet | seat S collides with the 1st guide part 87A is reduced.

  Further, the driving roller 82, the first pinch roller 83, the second pinch roller 84, and the first guide portion 87A are more inclined when the upper end portion 87A1 of the first guide portion 87A is not inclined. The space surrounded by the upper end portion 87A1 is widened. By tilting the upper end portion 87A1 of the first guide portion 87A, a wide space for bending the sheet S can be secured, and the deformation range in which the sheet S bends can be increased.

  Next, FIG. 14 will be described. 10 to 13, the shaft portion 84 </ b> A of the second pinch roller 84 is rotatably supported by the housing 2 around the first axis R <b> 1, but FIG. 14 illustrates the shaft portion 84 </ b> A of the second pinch roller 84. Is an embodiment that is not supported by the housing 2 but is rotatably supported by the holder 85.

  In FIG. 14, the rear end portion of the sheet S such as cardboard is in contact with the upper end portion A4 of the first pinch roller 83, and the first pinch roller 83 is separated from the driving roller 82 by the waist of the sheet S. is there. The highest upper end portion on the outer peripheral surface of the first pinch roller 83 is A4, and a line perpendicular to the line connecting the upper end portion A4 and the shaft portion 83A and passing through the upper end portion A4 is a vertical line H7.

  In FIG. 14, the upper end portion 87A1 and the upper end portion A4 of the first guide portion 87A are arranged at the same position in the vertical direction. The rear end portion of the sheet S in FIG. 14 passes through the upper end portion A4 of the first pinch roller 83, and further when the rear end portion is positioned further on the downstream side in the discharge direction than the upper end portion A4 of the first pinch roller 83. The first guide portion 87A is guided while being in contact with the upper end portion 87A1. Since there is no distance (step) between the upper end portion A4 and the upper end portion 87A1 of the first guide portion 87A, the rear end portion of the sheet S is guided smoothly without jumping. Thereby, the rear end portion of the sheet S is reduced in the collision sound that collides with the upper end portion 85G of the holder 85 or the upper end portion 87A1 of the first guide portion 87A.

  The discharge mechanism 81 can be arranged upside down. That is, when the curl direction of the sheet S conveyed to the discharge mechanism 81 is upside down with respect to the above embodiment, the discharge mechanism 81 may be arranged upside down.

  In the present embodiment, the first pinch roller 83 is held by the holder 85, and the urging means 86 urges the holder 85. However, the present invention is not limited to this. For example, the first pinch roller 83 has a bearing. The biasing means 86 may be disposed between the bearing portion and the holder to press the bearing portion. In this case, the holder 85 may be attached to the shaft portion 83A of the first pinch roller 83 and the shaft portion 84A of the second pinch roller 84, respectively.

  In the present embodiment, there is one urging means, but the present invention is not limited to this, and for example, there may be two or more urging means.

  In the present embodiment, the first pinch roller 83 and the second pinch roller 84 rotate following the driving roller 82, but the present invention is not limited to this, and for example, the first pinch roller 83 and the second pinch roller 84 are respectively It may be a drive roller.

  In the present embodiment, the discharge unit 8 as an example of the sheet discharge apparatus is configured in the electrophotographic image forming apparatus 1, but may be included in other types of image forming apparatuses such as an ink jet type. . Further, the discharge unit 8 may be provided in an image reading apparatus that reads an image of a read original document that is a sheet, for example, image processing other than the image formation of the image forming apparatus 1.

  In the present embodiment, the holder 85 is arranged such that the upper end portions 85G and 85H are above the line connecting the shaft portion 83A of the first pinch roller 83 and the shaft portion 84A of the second pinch roller 84, that is, near the drive roller 82. However, the present invention is not limited to this configuration. For example, the holder 85 may have a U-shape or other convex shape, and in this case, the upper end portions 85G and 85H are the shaft portion 83A of the first pinch roller 83 and the second pinch roller 84. It becomes the structure arrange | positioned below the line which connects 84A of axial parts.

[Effect of the embodiment]
A housing 2, a driving roller 82 that discharges the sheet along the discharging direction in the housing 2, and a first pinch roller 83 that is disposed at a position facing the driving roller 82 and rotates in contact with the driving roller 82. A second pinch roller that is disposed downstream of the first pinch roller 83 in the discharge direction and faces the drive roller 82 and rotates in contact with the drive roller 82, and the first pinch roller 83 and the second pinch roller. A holder 85 having a connecting portion to be connected and held, between a contact position where the first pinch roller 83 contacts the driving roller 82 and a spaced position where the first pinch roller 83 separates from the driving roller 82. A holder 85 for movably holding the one pinch roller 83; an urging means 86 for urging the first pinch roller 83 in the direction toward the drive roller 82; The guide member 87 is arranged at a predetermined position from the first pinch roller 83 to the second pinch roller, and the predetermined position is more than the connecting portion of the holder 85 when the first pinch roller 83 is located at the contact position. A guide member 87 which is a position away from the drive roller 82 and is closer to the drive roller 82 than a connecting portion of the holder 85 when the first pinch roller 83 is positioned at a separated position against the biasing means 86; .

  According to this configuration, when the stiff sheet S such as cardboard is conveyed, the first pinch roller 83 is separated from the driving roller 82 by the waist of the sheet S, and the sheet S is separated from the first pinch roller 83 or the second pinch roller 83. It is conveyed along one guide portion 87A. At this time, the step between the upper end portion of the separated first pinch roller 83 and the first guide portion 87A is the upper end portion of the first pinch roller 83 and the upper end portion 85G of the holder 85 when the first guide portion 87A is not provided. , 85H. Since the sheet is conveyed to the guide member 87 with a small step, the collision noise at the rear end of the sheet S is reduced. Further, since the jump at the rear end of the sheet S is reduced, the conveyance of the rear end of the sheet S can be stabilized.

  The guide member 87 has a sheet contact portion 87A1 that can come into contact with the end portion of the sheet discharged by the drive roller 82, and the contact position is the sheet of the guide member 87 in the direction in which the first pinch roller 83 approaches the drive roller 82. The position protruding from the contact portion 87A1 is in contact with the driving roller 82, and the separation position is a position where the first pinch roller 83 is separated from the driving roller 82 up to the arrangement position of the sheet contact portion 87A1 of the guide member 87.

  According to this configuration, the first pinch roller 83 is pressed by the stiff sheet S and displaced to the separated position, so that the rear end portion of the sheet S is not stepped from the upper end portion of the first pinch roller 83 without any step. Since the sheet is conveyed to the upper end portion 87A1 of the first guide portion 87A, it is possible to reduce the trailing end portion of the sheet S from jumping, and the collision noise can be further reduced.

  The holder 85 holds the first pinch roller 83 so that the first pinch roller 83 is separated to the maximum separation position H3 farthest from the drive roller 82, and the sheet contact portion 87A1 of the guide member 87 is the first pinch roller 83. Is located closer to the driving roller 82 than the portion A2 closest to the driving roller 82 on the outer periphery of the first pinch roller 83 when the first separation pin is separated to the maximum separation position H3.

  According to this configuration, since the separation amount of the first pinch roller 83 can be reduced, it is possible to reduce the collision noise that collides with the driving roller 82 when the first pinch roller 83 returns from the separation position to the contact position. .

  The second pinch roller 84 is held by the housing 2 and rotates about the first axis R1, and the first pinch roller 83 swings about the first axis R1.

  According to this configuration, since the second pinch roller 84 is not separated from the drive roller 82, the second pinch roller 84 is returned from the separated position to the contact position as compared with the case where both the first pinch roller 83 and the second pinch roller 84 are separated. The collision noise that the first pinch roller 83 collides with the driving roller 82 can be reduced. Further, since the second pinch roller 84 is not separated from the driving roller 82, the sheet S discharge direction can be stabilized.

  The guide member 87 is inclined in the direction away from the drive roller 82 from the first pinch roller 83 toward the second pinch roller in the discharge direction when the first pinch roller 83 and the second pinch roller are in contact with the drive roller 82. To do.

    According to this configuration, the driving roller 82, the first pinch roller 83, the second pinch roller 84, and the first pinion are in the inclined state rather than the upper end portion 87 </ b> A <b> 1 of the first guide portion 87 </ b> A not inclined. The space surrounded by the upper end portion 87A1 of the guide portion 87A becomes wider. By tilting the upper end portion 87A1 of the first guide portion 87A, a wide space for curving the sheet S to correct curl can be secured, and the deformation range in which the sheet S bends can be increased. .

  The guide members 87 are respectively disposed on both sides of the first pinch roller 83 in the rotation axis direction of the first pinch roller 83.

  According to this configuration, since the sheet S can be guided on both sides of the first pinch roller 83, the sheet S can be stably guided.

  When the first pinch roller 83 and the second pinch roller are in contact with the driving roller 82, the connecting portion of the holder 85 is in contact with the leading edge of the sheet discharged by the driving roller 82, and the leading edge of the sheet is second Guide to the pinch roller.

  According to this configuration, the leading edge of the sheet S is conveyed along the connecting portion of the holder 85, so that collision with other members is suppressed and the sheet S is conveyed smoothly.

  The diameter of the first pinch roller 83 is set to be smaller than the diameter of the second pinch roller.

  According to this configuration, since the moving range of the first pinch roller can be reduced, the size is reduced.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Housing | casing 82 Drive roller 83 1st pinch roller 84 2nd pinch roller 85 Holder 86 Energizing means 87 Guide member 87A 1st guide part R1 1st axis S sheet

Claims (12)

A housing,
A drive roller for discharging the sheet along the discharge direction in the housing;
A first pinch roller disposed at a position facing the drive roller and rotating in contact with the drive roller;
A second pinch roller that is disposed at a position facing the drive roller on the downstream side in the discharge direction from the first pinch roller, and rotates in contact with the drive roller;
A holder having a connecting portion for connecting and holding the first pinch roller and the second pinch roller, wherein the first pinch roller is in contact with the drive roller; and The holder for movably holding the first pinch roller between a separation position separated from the driving roller;
A biasing means for biasing the first pinch roller in a direction toward the driving roller;
A guide member disposed at a predetermined position from the first pinch roller to the second pinch roller in the discharge direction, wherein the predetermined position is the holder when the first pinch roller is positioned at the contact position; And a position closer to the drive roller than the connection portion of the holder when the first pinch roller is positioned at the separation position against the biasing means. A sheet discharging apparatus comprising: the guide member. The guide member has a sheet contact portion that can contact an end portion of a sheet discharged by the drive roller,
The contact position is a position where the first pinch roller protrudes from the sheet contact portion of the guide member in a direction approaching the drive roller and contacts the drive roller.
2. The sheet discharge device according to claim 1, wherein the separation position is a position where the first pinch roller is separated from the driving roller to a position where a sheet contact portion of the guide member is disposed. The holder holds the first pinch roller so that the first pinch roller is separated to a maximum separation position farthest from the drive roller,
The sheet contact portion of the guide member is disposed at a position closer to the drive roller than the portion closest to the drive roller on the outer periphery of the first pinch roller when the first pinch roller is separated to the maximum separation position. The sheet discharging apparatus according to claim 2. The second pinch roller is held by the housing and rotates about the first axis,
4. The sheet discharging apparatus according to claim 1, wherein the first pinch roller swings about the first axis. 5.   The guide member moves away from the drive roller in the discharge direction from the first pinch roller toward the second pinch roller in a state where the first pinch roller and the second pinch roller are in contact with the drive roller. The sheet discharging apparatus according to any one of claims 1 to 4, wherein the sheet discharging apparatus is inclined in a direction.   The sheet discharging apparatus according to any one of claims 1 to 5, wherein the guide members are respectively disposed on both sides of the first pinch roller in a rotation axis direction of the first pinch roller.   The connecting portion of the holder is in contact with the leading edge of the sheet discharged by the driving roller in a state where the first pinch roller and the second pinch roller are in contact with the driving roller. The sheet discharging apparatus according to any one of claims 1 to 6, wherein the sheet discharging apparatus guides toward the second pinch roller. A housing,
A drive roller for discharging the sheet along the discharge direction in the housing;
A first pinch roller disposed at a position facing the drive roller and rotating in contact with the drive roller;
A second pinch roller that is disposed at a position facing the drive roller on the downstream side in the discharge direction from the first pinch roller, and rotates in contact with the drive roller;
A connecting portion for connecting and holding the first pinch roller and the second pinch roller; a contact position where the first pinch roller contacts the driving roller; and the first pinch roller driving the drive A holder for movably holding the first pinch roller between a spaced position separated from the roller;
A biasing means for biasing the first pinch roller in a direction toward the driving roller;
The first pinch roller is disposed at a predetermined position away from the sheet discharged by the driving roller when the first pinch roller is positioned at the contact position, and is discharged by the driving roller when the first pinch roller is positioned at the separation position. A guide member that contacts the sheet to be guided and guides the sheet,
The predetermined position includes an arc surface defining an outer periphery of the first pinch roller facing each other and an outer periphery of the second pinch roller in a state where the first pinch roller and the second pinch roller are in contact with the driving roller. Is defined in a space formed by a circular arc surface to be defined,
The predetermined position is a position farther from the driving roller than a connecting portion of the holder when the first pinch roller is located at the contact position, and the first pinch roller resists the urging means. A sheet discharge device that is closer to the drive roller than the connecting portion of the holder when positioned at the separated position. The predetermined position is
In a state where the first pinch roller is located at the contact position, an arc that defines an outer periphery of the first pinch roller that faces each other, an arc that defines an outer periphery of the second pinch roller, and the drive roller that is close to the drive roller A first line segment connecting two intersecting points at which the lines defining the edge of the connecting portion of the holder intersect;
In a state where the first pinch roller is located at the separated position, an arc that defines the outer periphery of the first pinch roller facing each other, an arc that defines the outer periphery of the second pinch roller, and the drive roller are close to the arc A second line segment connecting two intersecting points where the lines defining the edge of the connecting portion of the holder intersect each other;
An arc defining an outer periphery of the first pinch roller facing each other and an arc defining an outer periphery of the second pinch roller in a state where the first pinch roller is located at the separated position;
In a state where the first pinch roller is located at the separated position, a line that passes through the rotation center of the first pinch roller and is perpendicular to the first line segment, and a circle that defines the outer periphery of the first pinch roller, respectively Out of two intersecting points, a specific intersecting point close to the driving roller and a third line segment connecting an intersection point on an arc defining the outer periphery of the first pinch roller defining the first line segment The sheet discharge device according to any one of claims 1 to 8, wherein the sheet discharge device is defined in a region to be stored. A housing,
A drive roller for discharging the sheet along the discharge direction in the housing;
A first pinch roller disposed at a position facing the drive roller and rotating in contact with the drive roller;
A second pinch roller that is disposed at a position facing the drive roller on the downstream side in the discharge direction from the first pinch roller, and rotates in contact with the drive roller;
A contact position where the first pinch roller and the second pinch roller are connected, and the first pinch roller contacts the drive roller, and a separation position where the first pinch roller separates from the drive roller A holder for movably holding the first pinch roller between
A biasing means for biasing the first pinch roller in a direction toward the driving roller;
The first pinch roller is disposed at a predetermined position away from the sheet discharged by the driving roller when the first pinch roller is positioned at the contact position, and is discharged by the driving roller when the first pinch roller is positioned at the separation position. A guide member that contacts the sheet to be guided and guides the sheet,
The predetermined position includes an arcuate surface defining an outer periphery of the first pinch roller facing each other in the discharge direction and the second pinch when the first pinch roller and the second pinch roller are in contact with the drive roller. A space formed by an arcuate surface that defines the outer periphery of the roller, the position of a line connecting the rotation center of the first pinch roller and the rotation center of the second pinch roller, or the drive from the line connecting A sheet discharge device defined in a space close to the rollers.   The sheet discharging apparatus according to any one of claims 1 to 10, wherein a diameter of the first pinch roller is set to a diameter smaller than a diameter of the second pinch roller. A sheet discharging apparatus according to any one of claims 1 to 11,
An image processing unit that is disposed on the upstream side of the sheet discharging device in the discharging direction and that performs image processing on the sheet;
An image processing apparatus comprising:

Images