Post-processing apparatus and image forming apparatus

Abstract

To discharge a plurality of recording media in an aligned state while suppressing cost.SOLUTION: The post-processing apparatus includes a placement plate on which a plurality of recording media are stacked, a sheet discharge tray to which the plurality of recording media are discharged, a conveyance unit 200 that conveys a bundle of the plurality of recording media stacked on the placement plate to the sheet discharge tray, and a single drive unit 300 that drives the conveyance unit 200, wherein the conveyance unit 200 includes a gripping unit that grips the plurality of recording media stacked on the placement plate, a gripping unit conveyance unit 210 that moves the gripping unit gripping the plurality of recording media in a sheet discharge direction from the placement plate toward the sheet discharge tray, and a swing drive mechanism M2 that reciprocates the gripping unit conveyance unit 210 along a direction parallel to the sheet discharge direction.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a post-processing device and an image forming apparatus, and more particularly to a post-processing device that post-processes recording media, and an image forming apparatus equipped with the post-processing device. [Background technology]

[0002] Image forming devices, such as MFPs (Multi Function Peripherals), may be equipped with post-processing devices. The post-processing devices discharge a stack of multiple sheets of paper onto which images have been formed by the MFP, onto a paper output tray. It is preferable that the stack of multiple recording media to be discharged onto the paper output tray be aligned.

[0003] For example, Patent No. 4774362 describes a sheet processing device that includes a loading means for temporarily receiving and loading sheet materials that have been transported, a binding means for binding the multiple sheet materials loaded on the loading means, a first transport means that contacts the rear ends of the multiple sheet materials that have been bound and transports the sheet materials to a transfer position, a second transport means that takes over transport from the first transport means after the transfer position and transports the sheet materials from the loading means, a drive means that drives the first and second transport means with the rotational drive force of a single drive source, and a drive conversion means that linearly converts the rotational movement of the drive means into reciprocating movement, wherein the drive conversion means has a cam and a cam follower, and the first transport means is set to a stopped state at the transfer position for a predetermined time depending on the shape of the contact portion between the cam and the cam follower.

[0004] However, in the sheet processing apparatus described in Japanese Patent No. 4774362, since the sheet members are transferred from the first conveying means to the second conveying means, the aligned sheet members may become misaligned during the transfer.

[0005] Furthermore, Japanese Patent Application Laid-Open No. 2011-6195 discloses a sheet stacking device that stacks sheets from a sheet discharge outlet in a bundle at a predetermined position on a tray, the device comprising: a sheet discharge outlet; tray means for stacking the sheets from the sheet discharge outlet; sheet discharge means for transporting the sheets toward a sheet end reference position on the tray means; side alignment means for aligning the sheet discharge orthogonal direction of the sheets sent by the sheet discharge means with a sheet side reference position; gripper means for moving the sheet bundle stacked on the tray means; grip conveyance drive means for moving the gripper means along the tray means; and control means for controlling the sheet discharge means, side alignment means, and gripper means. The gripper means is composed of a fixed gripper member that engages with the bottom sheet of the sheet stack, a movable gripper member that engages with the top sheet, and a grip opening / closing drive means that opens and closes the movable gripper member between a standby position retracted from the top sheet and a grip position where it engages with the top sheet, and the control means positions the sheet from the sheet discharge outlet at a predetermined position on the tray means using the sheet discharge means and the side alignment means, and then uses the grip opening / closing drive means to move the movable gripper member from the standby position to the grip position to press the edge of the sheet, and then return it to the standby position.This sheet accumulation device is characterized in that the gripper means is composed of a fixed gripper member that engages with the bottom sheet of the sheet stack, a movable gripper member that engages with the top sheet, and a grip opening / closing drive means that opens and closes the movable gripper member between a standby position retracted from the top sheet and a grip position where it engages with the top sheet, and

[0006] However, the sheet accumulation device described in JP 2011-6195 A must use two drive sources: one for the gripper means and one for the grip conveying drive means, which increases manufacturing costs and requires control to synchronize the gripper means and the grip conveying drive means, making processing more complicated. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4774362 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-6195 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a post-processing device that can eject a plurality of recording media in an aligned state while suppressing costs.

[0009] Another object of the present invention is to provide an image forming apparatus that can eject a plurality of recording media in an aligned state while suppressing the cost of the post-processing device. [Means for solving the problem]

[0010] According to one aspect of the present invention, a post-processing device includes an alignment section in which multiple recording media are loaded, a media receiving section to which the multiple recording media are discharged, a transport section that transports the stack of multiple recording media loaded in the alignment section to the media receiving section, and a single drive section that drives the transport section, wherein the transport section includes a gripping section that grips the multiple recording media loaded in the alignment section, a gripping section transport section that moves the gripping section, while holding the multiple recording media, in a paper discharge direction from the alignment section toward the media receiving section, and a reciprocating movement mechanism that moves the gripping section transport section back and forth along a direction parallel to the paper discharge direction.

[0011] According to another aspect of the present invention, an image forming apparatus includes the above-described post-processing device. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a first perspective view showing the appearance of an MFP according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view schematically illustrating an example of the internal configuration of an MFP. [Figure 3] 1 is a perspective view of a post-processing device according to an embodiment of the present invention; [Figure 4] 1 is a perspective view showing an example of an internal configuration of a post-processing device according to an embodiment of the present invention; [Figure 5] FIG. 2 is a side view showing an example of the internal configuration of the post-processing device according to the present embodiment. [Figure 6]FIG. 2 is a first plan view showing an example of an alignment unit of the post-processing device. [Figure 7] FIG. 2 is a first perspective view showing an example of a transport unit. [Figure 8] FIG. 2 is a perspective view showing an example of a gripper transport unit. [Figure 9] 10 is a first diagram showing an example of the positional relationship between a guide side plate and a gripping portion. FIG. [Figure 10] FIG. 10 is a second diagram showing an example of the positional relationship between the guide side plate and the gripping portion. [Figure 11] FIG. 2 is a second perspective view showing an example of a transport unit. [Figure 12] FIG. 2 is a first side view of the swing drive mechanism. [Figure 13] FIG. 10 is a second side view of the swing drive mechanism. [Figure 14] FIG. 10 is a third side view of the swing drive mechanism. [Figure 15] FIG. 10 is a fourth side view of the swing drive mechanism. [Figure 16] 10 is a first diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. FIG. [Figure 17] 10 is a second diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. FIG. [Figure 18] 10 is a third diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. FIG. [Figure 19] FIG. 4 is a fourth diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. [Figure 20] FIG. 5 is a fifth diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. [Figure 21] FIG. 10 is a first side view showing an example of a gripping unit release mechanism. [Figure 22] FIG. 10 is a second side view showing an example of a gripping unit release mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components are designated by the same reference numerals. The names and functions of these components are also the same. Therefore, detailed description thereof will not be repeated.

[0014] FIG. 1 is a first perspective view showing the appearance of an MFP according to one embodiment of the present invention. Referring to FIG. 1, MFP (Multi Function Peripheral) 1 is an example of an image forming apparatus. Here, an X direction, a Y direction, and a Z direction are defined, which intersect perpendicularly with each other. The X direction and the Y direction are parallel to the horizontal plane. Within the Y direction, the direction from the rear to the front of MFP 1 (the direction from the positive side to the negative side in the Y direction) is referred to as the front direction, and the horizontal direction from the front to the rear (the direction from the negative side to the positive side in the Y direction) is referred to as the rear direction.

[0015] 2 is a cross-sectional view showing an example of the internal configuration of an MFP. Referring to FIGS. 1 and 2, MFP 1 includes a document reading unit 2 that reads a document, an image forming unit 3 that forms an image on a sheet based on image data, a paper feed unit 4 that supplies paper to image forming unit 3, and a post-processing device 100 that performs post-processing on the paper on which the image has been formed.

[0016] The document reading unit 2 exposes the image of a document set on a document glass 11 with an exposure lamp 13 attached to a slider 12 that moves below the document glass. Light reflected from the document is guided to a lens 16 by a mirror 14 and two reflecting mirrors 15 and 15A, and forms an image on a CCD (Charge Coupled Devices) sensor 18.

[0017] The reflected light that forms an image on the CCD sensor 18 is converted into image data as an electrical signal within the CCD sensor 18. The image data is converted into printing data in cyan (C), magenta (M), yellow (Y), and black (K) and output to the image forming unit 3.

[0018] The image forming unit 3 includes image forming units 20Y, 20M, 20C, and 20K for yellow, magenta, cyan, and black, respectively. Here, "Y," "M," "C," and "K" represent yellow, magenta, cyan, and black, respectively. An image is formed by driving at least one of the image forming units 20Y, 20M, 20C, and 20K. A full-color image is formed by driving all of the image forming units 20Y, 20M, 20C, and 20K. Printing data for yellow, magenta, cyan, and black are input to the image forming units 20Y, 20M, 20C, and 20K, respectively. The image forming units 20Y, 20M, 20C, and 20K differ only in the color of the toner they handle. Therefore, the image forming unit 20Y for forming a yellow image will be described here.

[0019] The image forming unit 20Y includes an exposure device 21Y, a photosensitive drum 23Y, a charging roller 22Y, a developing unit 24Y, and a primary transfer roller 25Y. Around the photosensitive drum 23Y, the charging roller 22Y, the exposure device 21Y, the developing unit 24Y, the primary transfer roller 25Y, and the drum cleaning blade 27Y are arranged in this order along the rotational direction of the photosensitive drum 23Y. Yellow printing data is input to the exposure device 21Y. The photosensitive drum 23Y is an image carrier. The charging roller 22Y uniformly charges the surface of the photosensitive drum 23Y. The primary transfer roller 25Y transfers the toner image formed on the photosensitive drum 23Y onto an intermediate transfer belt 30, which is also an image carrier, by the action of an electric field.

[0020] After being charged by the charging roller 22Y, the photoreceptor drum 23Y is irradiated with laser light emitted by the exposure device 21Y. The exposure device 21Y exposes the image-corresponding portion of the surface of the photoreceptor drum 23Y. This forms an electrostatic latent image on the photoreceptor drum 23Y. Next, the developing device 24Y develops the electrostatic latent image formed on the photoreceptor drum 23Y with charged toner. Specifically, toner is placed on the electrostatic latent image formed on the photoreceptor drum 23Y by the action of electric field force, thereby forming a toner image on the photoreceptor drum 23Y. The toner image formed on the photoreceptor drum 23Y is transferred onto the intermediate transfer belt 30, which is an image carrier, by the action of electric field force using the primary transfer roller 25Y. Any toner remaining on the photoreceptor drum 23Y that has not been transferred is removed from the photoreceptor drum 23Y by the drum cleaning blade 27Y.

[0021] The intermediate transfer belt 30 is suspended tightly by a drive roller 33 and a driven roller 34. When the drive roller 33 rotates counterclockwise in FIG. 2, the intermediate transfer belt 30 rotates counterclockwise in the drawing at a predetermined speed. As the intermediate transfer belt 30 rotates, the driven roller 34 rotates counterclockwise.

[0022] As a result, the image forming units 20Y, 20M, 20C, and 20K sequentially transfer toner images onto the intermediate transfer belt 30. The timing at which each of the image forming units 20Y, 20M, 20C, and 20K transfers a toner image onto the intermediate transfer belt 30 is adjusted based on the detection of the reference marks on the intermediate transfer belt 30. As a result, yellow, magenta, cyan, and black toner images are superimposed on the intermediate transfer belt 30.

[0023] The toner image formed on the intermediate transfer belt 30 is transferred to paper by the action of electric field force by the secondary transfer roller 26, which is a transfer member. The paper is transported by timing roller 31 to a nip portion where the intermediate transfer belt 30 and secondary transfer roller 26 come into contact. The paper with the transferred toner image is transported to fixing roller 32, where it is heated and pressed. This melts the toner and fixes it to the paper. The paper is then transported to post-processing device 100.

[0024] Paper of different sizes is set in paper feed cassettes 35 and 35A, respectively. The paper stored in paper feed cassettes 35 and 35A is supplied to conveyance path 39 by take-out rollers 36 and 36A attached to paper feed cassettes 35 and 35A, respectively, and sent to timing rollers 31 by paper feed roller 37.

[0025] When forming a full-color image, the MFP 1 drives all of the image forming units 20Y, 20M, 20C, and 20K. When forming a monochrome image, the MFP 1 drives only one of the image forming units 20Y, 20M, 20C, and 20K. It is also possible to form an image by combining two or more of the image forming units 20Y, 20M, 20C, and 20K. Here, we will explain an example in which the MFP 1 employs a tandem system equipped with image forming units 20Y, 20M, 20C, and 20K that form four color toners on paper. However, the MFP 1 may also form images using a four-cycle system in which four color toners are transferred sequentially onto paper using a single photosensitive drum.

[0026] The post-processing device 100 is disposed in the storage space between the image forming unit 3 and the document reading unit 2 of the MFP 1. The post-processing device 100 is disposed on a slide surface 40, which is the upper surface of the top plate of a housing that houses the image forming unit 3, in a state where it can slide in the X direction.

[0027] FIG. 3 is a perspective view of a post-processing device according to the present embodiment. FIG. 4 is a perspective view showing an example of the internal configuration of a post-processing device according to the present embodiment. FIG. 5 is a side view showing an example of the internal configuration of a post-processing device according to the present embodiment. With reference to FIGS. 3 to 5, post-processing device 100 has main body housing 101. Main body housing 101 has main body rear section 140 that protrudes toward the positive side in the X direction. Main body rear section 140 is a part of main body housing 101 and includes a part of bottom surface 142 of main body housing 101. Main body rear section 140 has operation surface 141 that faces upward, opposite bottom surface 142. Guide groove 144A extending in the X direction is formed in operation surface 141. Operation unit 144 is slidably attached to guide groove 144A. Operation unit 144 is attached to operation surface 141 in a state where it is guided by guide groove 144A and is slidable in the X direction. When the user slides operation unit 144 along guide groove 144A, post-processing device 100 slides in the X direction on slide surface 40 and is pulled out from the main body of MFP1.

[0028] The post-processing device 100 has a paper output tray 109 connected to the main body housing 101 above the main body rear section 140. The post-processing device 100 has a transport path 108, receiving rollers 105, transport rollers 106, an alignment unit 110, a paddle 147, a transport unit 200, and a stapler 145 inside the main body housing 101. The transport path 108 connects the receiving opening 103 and the discharge opening 104. The receiving opening 103 is an opening formed on the side of the main body housing 101 opposite to the side to which the paper output tray 109 is connected. The receiving opening 103 is connected to the transport path 39 of the MFP 1. The direction from the receiving opening 103 toward the discharge opening 104 is the transport direction in which paper is transported. The receiving rollers 105 and the transport rollers 106 are arranged in this order on the transport path 108 between the receiving opening 103 and the discharge opening 104 along the transport direction. The paper on which an image is formed by the MFP 1 passes through the transport path 39 of the MFP 1 and is received at the receiving port 103 of the post-processing device 100. The paper received at the receiving port 103 is transported by the receiving rollers 105 toward the transport rollers 106. The paper transported by the transport rollers 106 is transported toward the discharge port 104.

[0029] A paddle 147 is disposed in the space downstream of the discharge port 104 in the paper transport direction. The paddle 147 is movable in the vertical direction. While the paper is transported along the transport path 108, the paddle 147 is positioned at an upper position, forming a space downstream of the discharge port 104. As a result, the leading edge of the paper transported by the transport rollers 106 is transported toward the paper output tray 109, and the paper is discharged into the space downstream of the discharge port 104. When the trailing edge of the paper transported by the transport rollers 106 passes through the discharge port 104, the paddle 147 moves downward. As the paddle 147 descends, the paper descends toward the alignment unit 110. The paddle 147 is driven by a belt and rotates counterclockwise in the figure. As a result, the paper sandwiched between the paddle 147 and the alignment unit 110 is transported in the opposite direction to the transport direction. The paper receives a force from the paddle 147 in a direction toward the negative X-direction on the alignment unit 110.

[0030] An insertion slot 102 is formed in the front direction (negative side in the Y direction) of the paper discharge tray 109 of the main body housing 101. When a user inserts a first stack of multiple sheets of paper into the insertion slot 102, staples are driven into the first stack.

[0031] FIG. 6 is a first plan view showing an example of an alignment unit of a post-processing device. Referring to FIG. 6, the alignment unit 110 includes a first alignment unit 110L and a second alignment unit 110R arranged side by side at a predetermined distance in the Y direction. The first alignment unit 110L and the second alignment unit 110R have a symmetrical configuration in the XZ plane. The reference numerals assigned to corresponding components of the first alignment unit 110L and the second alignment unit 110R include the same reference numerals. To distinguish between the components of the first alignment unit 110L and the second alignment unit 110R, the letter L is added to the reference numerals assigned to the components of the first alignment unit 110L, and the letter R is added to the reference numerals assigned to the components of the second alignment unit 110R.

[0032] The first alignment section 110L includes a mounting plate 111L, a side regulating section 112L, a drive motor 113L, and an end regulating section 121L.

[0033] The loading plate 111L has a loading surface facing upward. Paper sheets are placed on the loading surface of the loading plate 111L. The edge restriction portion 121L is fixed to the edge of the loading plate 111L on the negative side in the X direction. The edge restriction portion 121L faces the positive side in the X direction and has a restriction surface that perpendicularly intersects with the upper surface of the loading plate 111L. A force is applied to the negative side in the X direction by the paddle 147 on multiple sheets of paper loaded on the loading plate 111L. The multiple sheets of paper loaded on the loading plate 111L abut against the restriction surface of the edge restriction portion 121L. The edge restriction portion 121L aligns the position of the negative side in the X direction of the second stack of multiple sheets.

[0034] The side regulating portion 112L is disposed on the loading plate 111L, and the side regulating portion 112R is disposed on the loading plate 111R. The side regulating portions 112L and 112R have alignment surfaces that face each other. The alignment surfaces are parallel to the X and Z directions. The side regulating portion 112L moves in the Y direction when driven by the drive motor 113L. The side regulating portion 112R moves in the Y direction when driven by the drive motor 113R. By adjusting the distance between the side regulating portions 112L and 112R, the positions in the Y direction of one or more sheets of paper placed on the loading plate 111L and the loading plate 111R are determined.

[0035] Therefore, the second stack of one or more sheets placed on the placing plates 111L and 111R has its position in the Y direction determined on the placing plates 111L and 111R by the edge regulating portions 121L and 121R.

[0036] The second stack, whose positions in the X and Y directions have been determined on the placement plates 111L and 111R, is stapled by the stapler 145.

[0037] A transport section 200 is disposed between the loading plate 111L and the loading plate 111R. The transport section 200 discharges one or more sheets of paper placed on the loading plate 111L and the loading plate 111R onto the paper discharge tray 109.

[0038] FIG. 7 is a first perspective view showing an example of the transport unit. Referring to FIG. 7, the transport unit 200 includes a gripper transport unit 210 and a circulation drive mechanism M1. The gripper transport unit 210 is attached to the main body housing 101 so as to be movable in a direction perpendicular to the Y direction and parallel to the respective mounting surfaces of the mounting plates 111L and 111R. The circulation drive mechanism M1 includes a drive unit 300, a first drive shaft 301, and a second drive shaft 305. The drive unit 300 is a drive source, such as a motor. The first drive shaft 301 has a rotation axis parallel to the Y direction. The first drive shaft 301 is rotatably supported by the main body housing 101. The first drive shaft 301 is connected to the drive unit 300 via a gear and rotates around the rotation axis by receiving a driving force from the drive unit 300. A first gear 303 is fixed to the first drive shaft 301.

[0039] The second drive shaft 305 has a rotation axis parallel to the Y direction. The rotation axis of the second drive shaft 305 is rotatably supported by the main body housing 101. A second gear 307 and a first pulley 309 (see FIG. 11) are fixed to the second drive shaft 305. The second gear 307 meshes with the first gear 303. Therefore, the driving force of the drive unit 300 is transmitted from the first drive shaft 301 via the second gear 307 and the first gear 303 to the second drive shaft 305, causing it to rotate around the rotation axis.

[0040] The circulation drive mechanism M1 further includes a second pulley 311, an adjustment pulley 313, and a drive belt 315. The second pulley 311 is supported by the guide side plate 251 in a state where it can rotate around its rotation shaft. The drive belt 315 is suspended between the adjustment pulley 313, the second pulley 311, and the first pulley 309. The adjustment pulley 313 is biased by a spring or the like in an outward direction to prevent the drive belt 315 from slackening. The first pulley 309 rotates in conjunction with the rotation of the second drive shaft 305. The second pulley 311 and the second pulley 311 rotate in conjunction with the rotation of the first pulley 309. The second pulley 311 is connected to the drive roller 243 of the circulating conveying unit 240 via a gear. Therefore, the driving force of the driving unit 300 is transmitted to the circulating conveying unit 240.

[0041] Fig. 8 is a perspective view showing an example of a gripper transport unit. Referring to Fig. 8, gripper transport unit 210 includes gripper 211, circulating transport unit 240, and two guide side plates 251. Circulating transport unit 240 is disposed between two guide side plates 251. Gripper 211 grips a plurality of sheets of paper stacked on loading plate 111L and loading plate 111R. Gripper 211 includes base 213 and movable portion 231.

[0042] 9 is a first diagram showing an example of the positional relationship between the guide side plate and the gripping portion. Referring to FIGS. 8 and 9, base portion 213 includes lower clamping portion 214, drive shaft 215, base wheel 217, base biasing member 219, and movable bearing 221. Lower clamping portion 214 has a lower clamping surface that faces upward. Drive shaft 215 has a shape that extends parallel to the Y direction and is positioned on base portion 213 at a position on the negative side of lower clamping portion 214 in the X direction.

[0043] The movable part 231 includes an upper clamping part 232, a movable shaft 233, a movable biasing member 235, a movable boss 237, and a sliding wheel 239. The movable shaft 233 is journaled by a movable bearing 221 of the base part 213. The movable part 231 is attached to the movable shaft 233 in a state where it can rotate about the axis of the movable shaft 233. The upper clamping part 232 has an upper clamping surface that faces downward at a position corresponding to the lower clamping surface of the lower clamping part 214. Therefore, by rotating the movable part 231 about the axis of the movable shaft 233, the distance between the upper clamping surface of the upper clamping part 232 and the lower clamping surface of the lower clamping part 214 varies. The movable part 231 is biased by the movable biasing member 235 in a direction approaching the base part 213. Therefore, when no external force is applied, the movable part 231 is urged by the movable urging member 235 to rotate around the axis of the movable shaft 233 in a direction approaching the base part 213. When no paper is present between the movable part 231 and the base part 213, the movable part 231 comes into contact with the base part 213. When paper is present between the movable part 231 and the base part 213, the paper is sandwiched between the movable part 231 and the base part 213.

[0044] One of the two guide side plates 251, the circulating conveying unit 240, and the other guide side plate 251 are arranged side by side in this order in the Y direction. The circulating conveying unit 240 includes an endless belt 241, a drive roller 243, a driven roller 245, and a drive bearing 247. The drive roller 243 and the driven roller 245 are fixed at their respective ends to the two guide side plates 251 in a state in which they can rotate around rotation axes parallel to the Y direction and spaced a predetermined distance apart in the X direction. The endless belt 241 is suspended by the drive roller 243 and the driven roller 245 so as not to slacken. The drive roller 243 rotates by receiving a driving force from the drive unit 300 (described later). The rotation of the drive roller 243 rotates the endless belt 241 and the driven roller 245. A drive bearing 247 extending in the Y direction is fixed to the outer circumferential surface of the endless belt 241.

[0045] The drive bearing 247 supports the drive shaft 215 of the base portion 213. Therefore, as the endless belt 241 rotates, the base portion 213 moves along the outer periphery of the endless belt 241, which is suspended between the drive roller 243 and the driven roller 245. The path along which the drive shaft 215 moves on the outer periphery of the endless belt 241 is called the circulation path. The drive shaft 215 moves in the positive X-direction in the upper straight portion of the circulation path. The upper straight portion of the circulation path is parallel to the paper discharge direction. The drive shaft 215 moves in the negative X-direction in the lower portion of the circulation path. The drive shaft 215 moves downward in the downward portion on the positive X-direction of both end portions connecting the straight portion and the lower portion. The drive shaft 215 moves upward in the upward portion on the negative X-direction of both end portions connecting the straight portion and the lower portion.

[0046] While drive shaft 215 moves along the upper straight portion of the circulation path, circulating conveyance unit 240 moves gripper 211, which is holding a plurality of recording media, in the paper discharge direction (positive side in the X direction) from loading plates 111L and 111R toward paper discharge tray 109. Therefore, circulating conveyance unit 240 moves gripper 211, which is holding a plurality of recording media, in the paper discharge direction from loading plates 111L and 111R toward paper discharge tray 109.

[0047] The two guide side plates 251 are symmetrical in the XZ plane. Here, the guide side plate 251 provided on the positive side in the Y direction will be described. The guide side plate 251 has a rail groove 253 and a guide surface 255 formed on the inner surface facing the other guide side plate 251, and a connection boss 257 extending in the Y direction formed on the outer surface opposite the inner surface.

[0048] A base wheel 217 is provided on the base portion 213 on the opposite side of the drive shaft 215 from the lower clamping portion 214. The base wheel 217 is biased by a base biasing member 219 in a counterclockwise direction toward the positive side of the Y direction around the drive shaft 215 in FIG. 9 . Therefore, the base wheel 217 is biased by the base biasing member 219 against the side wall of a rail groove 253 formed in the guide side plate 251. The base portion 213 moves along the rail groove 253 formed in the guide side plate 251. The rail groove 253 is determined so that the orientation of the base portion 213 along which the drive shaft 215 moves along the circulation path is such that the lower clamping surface of the lower clamping portion 214 faces upward. Therefore, while the gripping portion 211 moves along the circulation path, the orientation in which the lower clamping surface of the lower clamping portion 214 of the base portion 213 faces upward is maintained.

[0049] A guide surface 255 is formed at the end of the guide side plate 251 on the negative side in the X direction. The guide surface 255 is a plane parallel to the Y direction and intersecting the X direction and the Z direction. The guide surface 255 is disposed at a position a predetermined distance away from the rail groove 253 on the negative side in the X direction. A sliding wheel 239 is attached to the movable part 231 on the opposite side of the upper clamping part 232 with respect to the movable shaft 233. The sliding wheel 239 is attached to the movable part 231 in a state where it can rotate around a rotation axis parallel to the Y direction.

[0050] During a contact period, which is a part of the period during which the gripping unit 211 moves along the upward portion of the circulation path, the sliding wheel 239 contacts the guide surface 255. During this contact period, the base unit 213 maintains a position in which the lower clamping surface of the lower clamping unit 214 faces upward. The distance between the drive shaft 215 and the movable shaft 233 is constant. Therefore, during the contact period in which the drive shaft 215 moves along the circulation path, the movable unit 231 overcomes the biasing force of the movable biasing member 235 and rotates clockwise around the axis of the movable shaft 233 in FIG. 9. As a result, the upper clamping surface of the upper clamping unit 232 of the movable unit 231 moves in a direction away from the lower clamping surface of the lower clamping unit 214 of the base unit 213. At the contact position where the gripping portion 211 contacts the negative X-direction ends of multiple sheets of paper positioned on the loading plates 111L and 111R, the distance between the upper clamping surface of the upper clamping portion 232 of the movable portion 231 and the lower clamping surface of the lower clamping portion 214 of the base portion 213 is maximum.

[0051] FIG. 10 is a second diagram showing an example of the positional relationship between the guide side plates and the gripping unit. The figure shows a state in which the gripping unit 211 is in a contact position where it contacts the negative X-direction ends of multiple sheets positioned on the loading plates 111L and 111R. The upper clamping surface of the upper clamping unit 232 of the movable unit 231 is separated from the lower clamping surface of the lower clamping unit 214 of the base unit 213. The contact position is the negative X-direction end of the upper straight portion of the circulation path. The contact position may also be the top end of the ascending portion of the circulation path. This allows multiple sheets to be positioned between the upper clamping surface of the upper clamping unit 232 of the movable unit 231 and the lower clamping surface of the lower clamping unit 214 of the base unit 213. Furthermore, when the drive shaft 215 moves in the paper discharge direction along the upper straight portion of the circulation path, the sliding wheel 239 no longer contacts the guide surface 255. When the sliding wheel 239 is no longer in contact with the guide surface 255, the movable part 231 is urged by the movable urging member 235 in a direction approaching the base part 213. As a result, multiple sheets of paper are gripped by the upper clamping part 232 of the movable part 231 and the lower clamping part 214 of the base part 213.

[0052] During the contact period, the distance between guide surface 255 and the circulation path is adjusted so as to shorten the distance between movable shaft 233 and guide surface 255. At the contact position, the distance between guide surface 255 and rail groove 253 is adjusted so as to maximize the distance between the upper clamping surface of upper clamping portion 232 of movable part 231 and the lower clamping surface of lower clamping portion 214 of base part 213.

[0053] 11 is a second perspective view showing an example of the transport unit. Referring to FIG. 11, the transport unit 200 further includes a swing drive mechanism M2. The swing drive mechanism M2 is disposed on the opposite side of the gripper transport unit 210 from the circulation drive mechanism M1. The swing drive mechanism M2 includes a crank gear 261 and a swing arm 281.

[0054] Fig. 12 is a first side view of the swing drive mechanism. Referring to Fig. 12, swing arm 281 includes a base shaft 283, a connecting groove 285, and a guide groove 287. Base shaft 283 has an axis parallel to the Y direction, and is rotatably fixed to main body housing 101. Swing arm 281 is rotatable around the axis of base shaft 283. Connection groove 285 of swing arm 281 has a shape that extends in a radial direction relative to the axis of base shaft 283, and is a hole that penetrates in the Y direction. Connection groove 285 of swing arm 281 is penetrated by connection boss 257 of guide side plate 251.

[0055] The crank gear 261 has a rotation shaft. The rotation shaft of the crank gear 261 is rotatably supported by the main body housing 101. The crank gear 261 has a toothed wheel formed on its outer periphery. The crank gear 261 meshes with the first gear 303. Therefore, the driving force of the driving unit 300 is transmitted to the crank gear 261 via the first driving shaft 301 and the first gear 303.

[0056] The crank gear 261 has a crank boss 263 extending in a direction parallel to the Y direction. The crank boss 263 fits into a guide groove 287 of the swing arm 281. The guide groove 287 includes two first and second arc portions 288A and 288B, and two first and second linear portions 289A and 289B. The first and second arc portion 288A and 288B are positioned opposite each other, and the two first and second linear portions 289A and 289B are positioned opposite each other. The two first and second arc portions 288A and 288B are positioned between the two first and second linear portions 289A and 289B. The two first arc portions 288A and the two second arc portions 288B are connected to the two first straight line portions 289A and the two second straight line portions 289B, respectively. The two first arc portions 288A and the two second arc portions 288B have a shape equal to the arc-shaped region of the path of rotation of the crank boss 263. In other words, the two first arc portions 288A and the two second arc portions 288B have an arc shape with a radius equal to the orbital radius of the rotating crank boss. The central angle of each of the two first arc portions 288A and the two second arc portions 288B is smaller than 180 degrees. The central angle of each of the two first arc portions 288A and the two second arc portions 288B is determined based on the distance over which the circulating conveying unit 240 reciprocates in a direction parallel to the paper discharge direction.

[0057] 12, the rotation trajectory of the crank boss 263 is indicated by a dotted line. The center of rotation of the crank boss 263 is the center of rotation of the crank gear 261. The two first straight line portions 289A and the second straight line portion 289B are arranged side by side in the direction of extension of a straight line passing through the base shaft 283, and the two arc portions 288 are arranged between the two first straight line portions 289A and the second straight line portion 289B.

[0058] 12 shows a state in which the crank boss 263 is positioned at the first arc portion 288A. The crank gear 261 rotates counterclockwise. While the crank boss 263 is positioned at the first arc portion 288A, the swing arm 281 does not rotate around the base shaft 283. Therefore, the gripper transport section 210 does not move in a direction parallel to the paper discharge direction. When the crank gear 261 rotates further, the crank boss 263 enters the first straight portion 289A.

[0059] 13 is a second side view of the swing drive mechanism. With crank boss 263 positioned at first linear portion 289A, swing arm 281 rotates clockwise around base shaft 283. Accordingly, gripper transport unit 210 moves in the direction opposite to the paper discharge direction (the direction indicated by the arrow in FIG. 12). Furthermore, as crank gear 261 rotates, crank boss 263 enters second arc portion 288B.

[0060] 14 is a third side view of the swing drive mechanism. While the crank boss 263 is positioned at the second arc portion 288B, the swing arm 281 does not rotate around the base shaft 283. Therefore, the gripper transport unit 210 does not move in a direction parallel to the paper discharge direction. Furthermore, when the crank gear 261 rotates, the crank boss 263 enters the second straight portion 289B.

[0061] 15 is a fourth side view of the swing drive mechanism. When crank boss 263 is positioned at second straight section 289B, swing arm 281 rotates counterclockwise around base shaft 283. Accordingly, gripper transport section 210 moves in the paper discharge direction (the direction indicated by the arrow in FIG. 15).

[0062] In this way, the circulation drive mechanism M1 and the swing drive mechanism M2 operate by receiving a driving force transmitted from a common drive unit 300. The circulation drive mechanism M1 transmits the driving force of the drive unit 300 to the gripper transport unit 210. The gripper transport unit 210 moves the gripper 211 along the circulation path. When the gripper 211 is located in the ascending portion of the circulation path, the gripper transport unit 210 causes the gripper 211 to grip multiple sheets of paper. The gripper transport unit 210 moves the gripper 211 in the paper discharge direction in the upper straight portion of the circulation path. When the gripper 211 is located in the descending portion of the circulation path, the gripper transport unit 210 causes the gripper 211 to release multiple sheets of paper. When the gripper 211 is located in the lower portion of the circulation path, the gripper transport unit 210 moves the gripper 211 in the direction opposite to the paper discharge direction.

[0063] The swing drive mechanism M2 reciprocates the gripper transport unit 210 in a direction parallel to the paper discharge direction. The swing drive mechanism M2 rotates the swing arm 281 clockwise or counterclockwise about the axis of the base shaft 283 by fitting a crank boss 263 provided on the crank gear 261 into a connecting groove 285 formed in the swing arm 281. When the swing arm 281 rotates clockwise or counterclockwise about the axis of the base shaft 283, the swing arm 281 swings, and the gripper transport unit 210 reciprocates in a direction parallel to the paper discharge direction.

[0064] In this embodiment, the drive unit 300 synchronizes the movement of the gripper 211 by the gripper transport unit 210 with the reciprocating movement of the gripper transport unit 210 by the swing drive mechanism M2. The drive unit 300 drives the circulation drive mechanism M1 and the swing drive mechanism M2 to move the gripper transport unit 210 back and forth once while the gripper transport unit 210 moves the gripper 211 around once along the circulation path. In this case, the position of the gripper 211 transported along the circulation path by the gripper transport unit 210 is synchronized with the position of the gripper transport unit 210, which is moved back and forth in a direction parallel to the paper discharge direction by the swing arm 281. The rotation angle of the crank gear 261 and the position of the gripper 211 in the circulation path are adjusted. The rotation angle of the crank gear 261 is determined by the position of the crank boss 263.

[0065] FIG. 16 is a first diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. FIG. 16 shows a state in which gripper transport unit 210 has moved to the furthest position toward the paper discharge direction. Also, crank boss 263 of crank gear 261 is positioned at first arc portion 288A of base shaft 283 of swing arm 281, just before entering first straight portion 289A. In this state, gripper 211 is positioned at a lower position in the circulation path along endless belt 241. Also, gripper 211 is in a state in which the upper clamping surface of movable portion 231 and the lower clamping surface of base portion 213 are in contact with each other. Gripper 211 moves in the opposite direction to the paper discharge direction in the circulation path.

[0066] FIG. 17 is a second diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. FIG. 17 shows a state in which the gripper transport unit 210 has moved furthest away from the paper discharge direction. The crank boss 263 of the crank gear 261 is positioned at the second arc portion 288B of the base shaft 283 of the swing arm 281, just before entering the second straight portion 289B. In this state, the gripper 211 is positioned at an elevated portion on the negative side of the X-direction in the circulation path along the endless belt 241. The sliding wheel 239 of the movable unit 231 is in contact with the guide surface 255 of the guide side plate 251, and the upper clamping surface of the movable unit 231 is furthest away from the lower clamping surface of the base unit 213. When the movable part 231 moves in the paper discharge direction and the movable shaft 233 of the movable part 231 is positioned in the end restriction part 121L, the sliding wheel 239 no longer abuts against the guide surface 255. As a result, the movable part 231 is urged by the movable urging member 235, and the movable part 231 moves in a direction in which its upper clamping surface approaches the lower clamping surface of the base part 213. As a result, the gripping part 211 grips one or more sheets of paper placed on the placement plates 111L, 111R.

[0067] Fig. 18 is a third diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. Fig. 19 is a fourth diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path.

[0068] As described above, the gripper transport unit 210 moves back and forth along the paper discharge direction. Fig. 18 shows the gripper transport unit positioned at the end of the path along which it moves back and forth, in the direction opposite to the paper discharge direction. Fig. 19 shows the gripper transport unit positioned at the end of the path along which it moves back and forth, in the direction toward the paper discharge direction.

[0069] 18 and 19 show a state in which gripper 211 is in the middle of moving in the paper discharge direction through the upper portion of the circulation path. In Fig. 19, gripper 211 is located closer to paper discharge tray 109 than gripper 211 shown in Fig. 18. That is, as gripper transport unit 210 moves in the paper discharge direction, gripper 211 moves in the paper discharge direction while gripping one or more sheets placed on loading plates 111L and 111R. Therefore, the one or more sheets are maintained in an aligned state while being transported in the paper discharge direction.

[0070] FIG. 20 is a fifth diagram showing an example of the relationship between the position of the gripper transport unit in the paper discharge direction and the position of the gripper in the circulation path. In FIG. 20, gripper 211 is located in the descending portion of the circulation path closest to the paper discharge tray 109. In the orbit along which gripper transport unit 210 reciprocates, gripper transport unit 210 stops for a predetermined time at the end position on the paper discharge direction side of the path along which gripper transport unit 210 reciprocates in the paper discharge direction. While gripper transport unit 210 is stopped at the end position on the paper discharge direction side, gripper 211 moves from the straight portion to the lower portion of the descending portion of the circulation path. Gripper 211 moves down the descending portion of the circulation path while gripping one or more sheets of paper. Therefore, one or more sheets of paper are placed on the paper discharge tray 109 while being gripped by gripper 211.

[0071] While the gripper transport unit 210 is stopped at the end of the path along which it reciprocates in the paper discharge direction, the gripper 211 moves in the direction opposite to the paper discharge direction to the middle of the lower part of the circulation path, thereby moving the gripper 211 to the position shown in FIG.

[0072] When gripping unit 211 moves to the lowest end of the descending portion of the circulation path, gripping unit 211 is gripping one or more sheets of paper. During the release period in which gripping unit 211 moves along the lower portion of the circulation path in the direction opposite to the paper discharge direction from the lower position of the circulation path to the position shown in Figure 16, gripping unit 211 releases one or more sheets of paper. As a result, one or more sheets of paper are placed on paper discharge tray 109 in an aligned state.

[0073] The transport unit 200 further includes a gripper release mechanism M3. FIG. 21 is a first side view showing an example of the gripper release mechanism. Referring to FIG. 21, the gripper release mechanism M3 includes a sliding arm 271 and a connecting member 277. The sliding arm 271 has a sliding shaft 273 and a sliding boss 275. The sliding shaft 273 has an axis extending in the Y direction and is rotatably supported by the main body housing 101. Therefore, the sliding arm 271 is rotatable around the axis of the sliding shaft 273. The sliding boss 275 has a cylindrical shape extending in the Y direction and is fixed to the sliding arm 271 at a position spaced a predetermined distance from the sliding shaft 273 of the sliding arm 271. The crank gear 261 has a cam 265 formed along its outer periphery. The sliding arm 271 is biased by an elastic member such as a spring in a direction (clockwise direction in FIG. 21 ) in which the sliding boss 275 moves around the axis of the sliding shaft 273 toward the cam 265 of the crank gear 261. Therefore, as the crank gear 261 rotates, the sliding arm 271 slides on the cam 265 of the crank gear 261 and is guided by the cam 265.

[0074] The sliding arm 271 is connected to a linking member 277 by a connecting shaft 276 at a connection portion that is a predetermined distance away from the sliding shaft 273 on the opposite side of the sliding boss 275 with respect to the sliding shaft 273. The sliding arm 271 and the connecting member 277 are rotatable around the axis of the connecting shaft 276.

[0075] The connecting member 277 has a connecting groove 279 formed at the end opposite to the portion connected to the connection shaft 276. The connecting groove 279 is a hole that penetrates the connecting member 277 in the Y direction. A movable boss 237 of the movable part 231 fits into the connecting groove 279. The movable boss 237 has a cylindrical shape that extends in the Y direction, and is fixed to the movable part 231 at a position that is a predetermined distance away from the movable shaft 233. The lengths of the connecting groove 279 in the X and Y directions that intersect with the Y direction are greater than the diameter of the movable boss 237. Therefore, the movable boss 237 is slidable along the inner wall of the connecting groove 279.

[0076] 22 is a second side view showing an example of the grip part release mechanism. Referring to FIG. 22, as crank gear 261 rotates, sliding boss 275 is pushed upward by cam 265 formed on crank gear 261. Sliding arm 271 rotates counterclockwise around the axis of sliding shaft 273. As a result, connecting shaft 276 moves downward, and coupling groove 279 of coupling member 277 moves downward. As coupling groove 279 moves downward, movable boss 237 of movable part 231 moves downward. As a result, movable part 231 rotates clockwise around the axis of movable shaft 233. As a result, movable part 231 of grip part 211 moves in a direction away from base part 213.

[0077] During the release period, the gripper release mechanism M3 moves the movable part 231 of the gripper 211 in a direction away from the base part 213. The release period is the period during which the gripper transport part 210 is positioned at the end of the path parallel to the sheet discharge direction that is closer to the sheet discharge direction, and during which the gripper 211 moves in the direction opposite to the sheet discharge direction in the lower part of the circulation path. Therefore, after the gripper 211 places one or more sheets of paper in an aligned state on the sheet discharge tray 109, it no longer grips the one or more sheets of paper and moves in the direction opposite to the sheet discharge direction.

[0078] <Correspondence between each element of the claims and each element of the embodiment> In this embodiment, loading plates 111L and 111R correspond to the alignment section in the claims, discharge tray 109 corresponds to the medium receiving section, gripper transport section 210 corresponds to the transport section, and drive section 300 corresponds to the drive section. Also, gripper 211 corresponds to the gripper, gripper transport section 210 corresponds to the gripper transport section, and swing drive mechanism M2 corresponds to the reciprocating movement mechanism.

[0079] Additionally, the crank gear 261 corresponds to the crank gear, and the swing arm 281 corresponds to the connecting member. The base shaft 283 corresponds to the base shaft, the connection boss 257 corresponds to the connection boss, the connection groove 285 corresponds to the guide groove, and the first arc portion 288A and the second arc portion 288B correspond to the arc-shaped portion.

[0080] Grip portion 211 corresponds to the grip portion, base portion 213 corresponds to the base portion, movable portion 231 corresponds to the movable portion, and movable biasing member 235 corresponds to the biasing member. Cam 265 corresponds to the cam formed along the circumferential direction of the crank gear, and grip portion release mechanism M3 corresponds to the grip portion release mechanism.

[0081] The guide side plate 251 corresponds to the guide portion, and the guide surface 255 corresponds to the guide surface that guides the movable portion. The circulating conveyance portion 240 corresponds to the circulating movement portion. The rail groove 253 of the guide side plate 251 corresponds to the attitude determination portion.

[0082] The end regulating portions 121L and 121R and the side regulating portions 112L and 112R correspond to the positioning portion, and the stapler 145 corresponds to the processing portion. The MFP 1 corresponds to the image forming apparatus.

[0083] <Summary of implementation form> (Item 1) An alignment unit on which a plurality of recording media are stacked; a medium receiving section to which a plurality of recording media are discharged; a conveying section that conveys a stack of the recording media loaded in the alignment section to the medium receiving section; a single drive unit that drives the conveying unit, the conveying unit includes a gripping unit configured to grip the plurality of recording media stacked in the alignment unit; a gripper transport unit that moves the gripper, holding the plurality of recording media, in a paper discharge direction from the alignment unit toward the medium receiving unit; a reciprocating mechanism that reciprocates the gripper transport unit in a direction parallel to the paper discharge direction.

[0084] According to this aspect, the gripping section grips multiple recording media loaded in the alignment section, and the gripping section moves while gripping the multiple recording media, allowing the multiple recording media to be discharged to the media receiving section in an aligned state. Furthermore, the gripping section transport section and the reciprocating mechanism that reciprocates the gripping section transport section are driven by a single drive section. This reduces the number of parts, lowering costs, and allows the gripping section transport section and the reciprocating mechanism to be synchronized. As a result, a post-processing device can be provided that can discharge multiple recording media in an aligned state while keeping costs down.

[0085] (Item 2) Further comprising a crank gear to which a driving force is transmitted from the driving unit, the reciprocating mechanism includes a connecting member rotatably attached to a base shaft and connected to a connecting boss extending from the gripper transport unit in a direction perpendicular to the paper discharge direction and the up-down direction; the connecting member is formed with a guide groove for guiding a crank boss provided on the crank gear, Item 2. The after-treatment device according to item 1, wherein the guide groove has an arc-shaped portion having a radius equal to the radius of the orbit of the crank boss.

[0086] According to this aspect, the connecting member does not rotate around the base axis while the crank boss is guided along the arc-shaped portion of the guide groove, thereby ensuring a period during which the gripper transport unit is stopped.

[0087] (Item 3) The gripping portion includes a base portion and a movable portion whose distance between the base portion and the movable portion is variable; a biasing member that biases the movable portion toward the base portion, Item 3. The post-processing device according to item 2, further comprising a gripping portion release mechanism that is guided by a cam formed along the circumferential direction of the crank gear and moves the movable portion in a direction away from the base portion.

[0088] According to this aspect, while the gripper transport unit is stopped, the gripper moves the movable unit in a direction away from the base unit. As a result, no force is applied to the multiple recording media gripped by the gripper in the direction in which the gripper transport unit moves back and forth, and the gripper no longer grips the multiple recording media. As a result, the multiple recording media can be ejected while maintaining their aligned state.

[0089] (Item 4) Further comprising a crank gear to which a driving force is transmitted from the driving unit, The gripping portion includes a base portion and a movable portion whose distance between the base portion and the movable portion is variable. a biasing portion that biases the movable portion toward the base portion, Item 1. The post-processing device described in item 1 further includes a gripping portion release mechanism that is guided by a cam formed along the circumferential direction of the crank gear and moves the movable portion in a direction away from the base portion.

[0090] According to this aspect, the movable part moves in a direction away from the base part, and the drive part causes the gripping part to stop gripping the multiple storage media. Therefore, it is possible to switch between gripping the multiple storage media and releasing the multiple storage media with a single drive part.

[0091] (Item 5) A post-processing device as described in item 3 or 4, further comprising a guide section having a guide surface for guiding the movable section, the guide section being positioned at a predetermined distance away from the transport section on the opposite side of the media receiving section.

[0092] According to this aspect, the movable part can be separated from the defining part only during the period in which the movable part is in contact with the guide surface during the period in which the movable part is being transported. Therefore, while the drive part is transporting the gripping part, the movable part can be operated to separate from the defining part before the gripping part grips the multiple storage media.

[0093] (Item 6) The gripper transport unit includes a circulation moving unit that circulates the gripper along a circulation path, 6. The post-processing device according to any one of items 1 to 5, wherein the drive unit causes the reciprocating mechanism to move the gripper transport unit back and forth once while the gripper transport unit moves the gripper unit around the circulation path once.

[0094] According to this aspect, the drive unit drives the gripper transport unit to make one reciprocating movement of the gripper transport unit while the drive unit drives the gripper transport unit to make one rotation around the circulation path, thereby enabling the movement of the gripper and the movement of the gripper transport unit to be synchronized.

[0095] (Item 7) The post-processing device according to Item 6, wherein the gripping section contacts the plurality of recording media positioned in the alignment section at an upstream end in the paper discharge direction while moving along the circulation path.

[0096] According to this aspect, the gripping portion contacts the plurality of recording media positioned in the alignment portion at the upstream end in the paper discharge direction while moving along the circulation path, and therefore, by pushing the plurality of recording media in the transport direction, the plurality of recording media can be transported in the paper discharge direction.

[0097] (Item 8) The post-processing device according to item 6, wherein the gripper transport unit includes a posture determining unit that determines a posture of the gripper in the circulation path.

[0098] According to this aspect, the posture of the gripping portion in the circulation path is determined, so that the gripping portion can accurately grip a plurality of recording media.

[0099] (Item 9) A positioning unit that positions the plurality of recording media loaded on the alignment unit with respect to the alignment unit; 6. The post-processing device according to any one of items 1 to 5, further comprising a processing unit that processes the plurality of recording media positioned by the positioning unit.

[0100] According to this aspect, the plurality of recording media placed on the alignment plate are aligned, so that the plurality of recording media can be processed at accurate positions.

[0101] (Item 10) An image forming apparatus equipped with the post-processing device according to any one of items 1 to 9.

[0102] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0103] 1 MFP, 2 document reading unit, 3 image forming unit, 4 paper feed unit, 39 transport path, 40 slide surface, 100 post-processing device, 101 main body housing, 102 insertion port, 103 receiving port, 104 discharge port, 105 receiving roller, 106 transport roller, 108 transport path, 109 paper output tray, 110 alignment unit, 110L first alignment unit, 110R second alignment unit, 111L, 111R loading plate, 112L, 112R side regulation unit, 113L, 113R drive motor, 121L, 121R edge regulation unit, 140 main body rear, 141 operation surface, 142 bottom surface, 144 operation unit, 144A guide groove, 145 stapler, 147 paddle, 200 transport unit, 210 Gripper conveying section, 211 Gripper, 213 Base section, 214 Lower clamping section, 215 Drive shaft, 217 Base wheel, 219 Base biasing member, 221 Movable bearing, 231 Movable section, 232 Upper clamping section, 233 Movable shaft, 235 Movable biasing member, 237 Movable boss, 239 Sliding wheel, 240 Circulating conveying section, 241 Endless belt, 243 Drive roller, 245 Driven roller, 247 Drive bearing, 251 Guide side plate, 253 Rail groove, 255 Guide surface, 257 Connecting boss, 261 Crank gear, 263 Crank boss, 265 Cam, 271 Sliding arm, 273 Sliding shaft, 275 Sliding boss, 276 Connecting shaft, 277 Connecting member, 279 Connecting groove, 281 Oscillating arm, 283 base shaft, 285 connecting groove, 287 guide groove, 288A first arc portion, 288B second arc portion, 289A first linear portion, 289B second linear portion, 300 drive portion, 301 first drive shaft, 303 first gear, 305 second drive shaft, 307 second gear, 309 first pulley, 311 second pulley, 313 adjusting pulley, 315 drive belt, M1 circulation drive mechanism, M2 oscillation drive mechanism, M3 grip portion release mechanism.

Claims

1. an alignment unit on which a plurality of recording media are stacked; a medium receiving section to which a plurality of recording media are discharged; a conveying section that conveys a stack of the recording media loaded in the alignment section to the medium receiving section; a single drive unit that drives the conveying unit, the conveying unit includes a gripping unit configured to grip the plurality of recording media stacked in the alignment unit; a gripper transport unit that moves the gripper, holding the plurality of recording media, in a paper discharge direction from the alignment unit toward the medium receiving unit; a reciprocating mechanism that reciprocates the gripper transport unit in a direction parallel to the paper discharge direction.

2. a crank gear to which a driving force is transmitted from the drive unit, the reciprocating mechanism includes a connecting member rotatably attached to a base shaft and connected to a connecting boss extending from the gripper transport unit in a direction perpendicular to the paper discharge direction and the up-down direction; the connecting member is formed with a guide groove for guiding a crank boss provided on the crank gear, The aftertreatment device according to claim 1 , wherein the guide groove has an arc-shaped portion having a radius equal to the radius of the orbit of the crank boss.

3. The gripping portion includes a base portion and a movable portion whose distance between the base portion and the movable portion is variable. a biasing member that biases the movable portion toward the base portion, The post-processing device according to claim 2 , further comprising a gripper release mechanism that is guided by a cam formed along the circumferential direction of the crank gear and moves the movable part in a direction away from the base part.

4. a crank gear to which a driving force is transmitted from the drive unit, The gripping portion includes a base portion and a movable portion whose distance between the base portion and the movable portion is variable. a biasing portion that biases the movable portion toward the base portion, The post-processing device according to claim 1 , further comprising a gripper release mechanism that is guided by a cam formed along the circumferential direction of the crank gear and moves the movable part in a direction away from the base part.

5. The post-processing device according to claim 4 , further comprising a guide unit having a guide surface that guides the movable unit, the guide unit being disposed at a predetermined distance away from the transport unit on the opposite side from the medium receiving unit.

6. The gripper transport unit includes a circulation moving unit that circulates the gripper along a circulation path, The post-processing device according to any one of claims 1 to 4, wherein the drive unit causes the reciprocating mechanism to move the gripper transport unit back and forth once while the gripper transport unit moves the gripper unit around the circulation path once.

7. The post-processing device according to claim 6 , wherein the gripping portion abuts against the plurality of recording media positioned in the alignment portion at an upstream end in the paper discharge direction while moving along the circulation path.

8. The post-processing device according to claim 6 , wherein the gripper transport unit includes a posture determining unit that determines a posture of the gripper in the circulation path.

9. a positioning unit that positions the plurality of recording media loaded on the alignment unit with respect to the alignment unit; 6. The post-processing device according to claim 1, further comprising: a processing unit that processes the plurality of recording media positioned by the positioning unit.

10. An image forming apparatus comprising the post-processing device according to any one of claims 1 to 5.

Images