JP2012229068A - Paper reversing device - Google Patents

Abstract

An object of the present invention is to quickly and appropriately reverse printed printing paper with a simple device configuration.
An inlet / outlet 401c for entering / exiting the printing paper W is provided, a reversing unit 401 for inverting the front and back of the printing paper W carried from the inlet / outlet 401c and guiding it to the inlet / outlet 401c, and the vicinity of the inlet / outlet 401c, Conveying means 402, 403, and 404 for carrying the printing paper W into the reversing unit 401 and carrying out the printing paper W reversed by the reversing unit 401 from the reversing unit 401. It is provided so as to be inclined with respect to the vertical direction, and is provided in a substantially vertical direction so that the carry-in guide 401a for guiding the printing paper W carried by the conveying means into the reversing unit 401 and the inlet / outlet 401c face downward. And a carry-out guide 401b for guiding the printing paper W to be carried out of the reversing unit 401 by the conveying means.
[Selection] Figure 2

Description

  The present invention relates to a sheet reversing device that inverts a sheet on which an image is formed by an image forming apparatus and supplies the sheet to a post-processing apparatus.

  In general, one-sided printing that prints on one side of printing paper, and a circulation conveyance path that includes a paper reversing path, prints on one side of the printing paper, and is printed on this one side. There is known an image forming apparatus (printing apparatus) capable of performing double-sided printing in which a sheet is reversed on the other side through a sheet reversing path and printing is performed on the other side.

  Used in combination with a post-processing device that is provided on the downstream side of such a printing device and performs post-processing such as stapling, punching, or cutting on printing paper that is printed and discharged by the printing device May be.

  Some print jobs for which post-processing execution is instructed include both single-sided printing and double-sided printing. If the post-processing by the post-processing device described above is required, the printing device In order to arrange the order of the printing papers discharged from the printing apparatus, all the printing papers must pass through the paper reversing path, and productivity (the number of processes per unit time) is correspondingly increased. There was a problem that it would decrease.

  In addition, there are two types of methods for discharging printing paper from the printing apparatus: face-up paper discharge in which the surface printed immediately before is discharged upward, and face-down paper discharge in a downward direction. When the post-processing device is connected to the paper discharge path using the face-up paper discharge method, and the job for which post-processing is instructed is single-sided printing, printing is performed sequentially with the first printed paper as the first page. In order to stack the printed sheets, it is necessary to reverse the front and back through the sheet reversing path and to supply it to the post-processing apparatus. Even in this case, it is necessary to transport the printing paper on the paper reversing path and the circulation transport path, and there is a problem that productivity is reduced correspondingly.

  In Patent Document 1 and Patent Document 2, a reverse conveying unit that reverses the front and back by switchback conveying in a horizontal direction or a downward direction, and a roller is driven by a driving force of a stepping motor in a paper unloading process from the reverse conveying unit. A paper reversing device having a toothed belt that conveys printing paper by rotating has been proposed.

JP 2003-54808 A Japanese Patent No. 2890916

  However, in the techniques described in Patent Document 1 and Patent Document 2, since the front and back are reversed by switchback conveyance in the horizontal direction or in the downward direction, a driving device such as a stepping motor is required to carry out the apparatus. The configuration was complicated.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a paper reversing device that quickly and appropriately reverses printed paper with a simple device configuration.

  In order to achieve the above object, the first feature of the paper reversing device according to the present invention is that the entrance for entering and exiting the printing paper is provided so as to face downward, and the front and back sides of the printing paper carried in from the entrance are reversed. And reversing means for guiding to the entrance / exit, and conveying means provided in the vicinity of the entrance / exit for carrying the printing paper into the reversing means and carrying out the printing paper reversed by the reversing means from the reversing means. There is.

  A second feature of the paper reversing device according to the present invention is that the reversing means is provided to be inclined with respect to the vertical direction so that the doorway faces downward, and the printing paper carried by the conveying means is reversed. A carry-in guide for guiding into the means, and a carry-out guide which is provided in a substantially vertical direction so that the inlet / outlet faces downward and guides the printing paper out of the reversing means by the conveying means. is there.

  A third feature of the paper reversing device according to the present invention is that it further comprises a paper stopping means arranged at a position where the leading edge of the printing paper carried by the conveying means is abutted.

  A fourth feature of the paper reversing device according to the present invention is a paper detecting means for detecting a printing paper carried by the conveying means, a position moving means for moving a position of the paper stopping means with respect to the reversing means, And a control means for controlling the position moving means so that the position of the paper stopping means relative to the reversing means is moved based on the detection result detected by the paper detecting means.

  A fifth feature of the paper reversing device according to the present invention is that the conveying means is provided in the vicinity of the entrance / exit and is driven to rotate, in the vicinity of the entrance / exit and is provided in pressure contact with the drive roller. A first driven roller that carries printing paper into the reversing means by being driven in accordance with the rotational drive, and is provided in pressure contact with the drive roller in the vicinity of the entrance / exit, and is driven in accordance with the rotational drive of the drive roller. Thus, a second driven roller for carrying out the printing paper from the reversing means is provided.

  According to the first feature of the paper reversing device according to the present invention, the entrance for entering and exiting the printing paper is provided so as to face downward, and the front and back of the printing paper carried from the entrance is reversed to the entrance. Since the inversion means for guiding is provided, the printed printing paper can be quickly and appropriately inverted with a simple apparatus configuration. Further, since the doorway is provided so as to face downward, it can be freely dropped by utilizing its own weight, and the printing paper can be reversed with a simple apparatus configuration.

  According to the second feature of the paper reversing device according to the present invention, the reversing means is provided with an inclination with respect to the vertical direction so that the inlet / outlet is directed downward, and the printing paper carried by the conveying means is placed in the reversing means. And a carry-out guide that is provided in a substantially vertical direction so that the inlet / outlet is directed downward and guides the printing paper to be carried out of the reversing means by the conveying means. By allowing the printing paper to fall freely, it can be carried out by the conveying means from the entrance. Also, since the carry-in guide and the carry-out guide are installed at a certain angle, the next printing paper can be carried into the reversing means without waiting for the completion of carrying out of the printing paper carried out from the reversing means. Can be improved.

  According to the third feature of the paper inverting device according to the present invention, the paper inverting device further includes paper stopping means arranged at a position where the leading edge of the printing paper carried in by the conveying means is abutted. Line correction can be performed.

  According to the fourth feature of the paper reversing device according to the present invention, the position moving means is controlled so that the position of the paper stopping means relative to the reversing means is moved, so that the paper stopping means according to the speed at which the printing paper is carried in The position of can be changed.

  According to the fifth feature of the sheet reversing device according to the present invention, a driving roller that is rotationally driven provided in the vicinity of the entrance / exit and a pressure roller that is provided in pressure contact with the driving roller in the vicinity of the entrance / exit, and is driven as the driving roller rotates. Thus, the first driven roller for bringing the printing paper into the reversing means and the driving roller are provided in pressure contact with the driving roller in the vicinity of the entrance and exit, and the printing paper is removed from the reversing means by being driven as the driving roller rotates. Since the second driven roller to be carried out is provided, two printing sheets can be present in the reversing means with a simple configuration, and high productivity can be exhibited.

1 is an overall configuration diagram illustrating an overall configuration of an image forming system according to an embodiment of the present invention. 1 is a configuration diagram illustrating a configuration of a sheet reversing device provided in an image forming system according to an embodiment of the present invention. 1 is a functional configuration diagram illustrating a functional configuration of an image forming system according to an embodiment of the present invention. (A)-(d) is the figure which showed the effect | action of the image forming system which is one Embodiment of this invention. It is the figure which showed the experimental result which performed the paper passing experiment by the image forming system which is one Embodiment of this invention.

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

  In one embodiment of the present invention, an image forming apparatus that discharges black and / or color ink from an inkjet head to perform printing on printing paper, a post-processing apparatus that performs post-processing such as stapling, and the image forming apparatus An image forming system including a paper reversing device that reverses the printing paper printed by the above and supplies it to the post-processing apparatus will be described as an example.

<Configuration of image forming system>
FIG. 1 is an overall configuration diagram showing an overall configuration of an image forming system according to an embodiment of the present invention.

  As shown in FIG. 1, the image forming system 1 is printed by an image forming apparatus 2 that performs printing on the printing paper W, a post-processing apparatus 3 that performs post-processing on the printing paper W, and the image forming apparatus 2. A paper reversing device 4 for reversing the printed paper and supplying it to the post-processing device 3 is provided.

  The image forming apparatus 2 includes a side paper feed unit 10, an internal paper feed unit 20, a printing unit (image forming unit) 30, a paper discharge unit 40, and a reversing unit 50.

  The side paper feeding unit 10 includes a paper feeding table 11 on which the printing paper W is stacked, and a primary paper feeding unit 12 that conveys only the uppermost printing paper W from the paper feeding table 11 onto the paper feeding conveyance path SR. And a secondary paper feeding unit 14 for carrying the printing paper W conveyed by the primary paper feeding unit 12 onto the circulation conveyance path CR. The printing paper W conveyed on the paper feeding conveyance path SR by the primary paper feeding unit 12 is abutted against the secondary paper feeding unit 14, whereby the alignment and skew correction of the leading edge of the printing paper W are performed. It is conveyed on the circulation conveyance path CR toward the printing unit 30 at a predetermined timing.

  The internal paper feeding unit 20 feeds and conveys only the uppermost printing paper W from the paper feeding bases 21a, 21b, 21c, and 21d on which the printing paper W is stacked and these paper feeding bases 21a, 21b, 21c, and 21d. Primary paper feeding sections 22a, 22b, 22c, and 22d that are transported onto the path SR are provided.

  The printing paper W transported onto the paper feed transport path SR by the primary paper feed sections 22a, 22b, 22c, and 22d is supplied by a plurality of transport rollers such as a transport roller 23 installed on the paper feed transport path SR. The paper is conveyed on the paper conveyance path SR and is abutted against the secondary paper supply unit 14. As a result, the printing paper W is slackened, and the slackness adjusts the position of the leading edge of the printing paper W and corrects the skew feeding. Thereafter, the printing paper W is conveyed on the circulation conveyance path CR toward the printing unit 30 at a predetermined timing. .

  In this way, the printing paper W is conveyed from the side paper feeding unit 10 and the internal paper feeding unit 20 to the secondary paper feeding unit 14, and further, the printing paper W is also conveyed from the reversing unit 50 described later.

  Therefore, in front of the secondary paper feed unit 14 in the transport direction, the transport path of the fed printing paper W and the paper for back side printing that is circulated through the apparatus after front side printing and reversed by the reversing unit 50 are provided. There is a merging point where the route that is conveyed in a circulating manner merges. Based on this merging point, the path on the paper feed mechanism side is called a paper feed transport path SR, and the path through which the printing paper W is circulated in the image forming apparatus 2 is called a circulation transport path CR.

  The printing unit 30 includes a head unit 31 in which a plurality of print heads are incorporated, and an annular conveyance belt 32 provided on the opposing surface of the head unit 31, and is fed by the secondary paper feeding unit 14. The printing paper W is printed on the printing paper W line by line with the ink ejected from the head unit 31 while being transported on the transport belt 32 at a speed determined by the printing conditions.

  The printing paper W printed by the printing unit 30 is conveyed on the circulation conveyance path CR in the housing by a conveyance roller or the like disposed on the circulation conveyance path CR. A switching mechanism 43 is provided on the circulation conveyance path CR to switch between guiding the printing paper W conveyed on the circulation conveyance path CR to the paper discharge unit 40 or recirculating it on the circulation conveyance path CR. Yes.

  The paper discharge unit 40 includes a tray-shaped paper discharge table 41 protruding from the housing of the image forming apparatus 2 and a pair of paper discharge rollers 42 that guide the print paper W to the paper discharge table 41. Then, the printing paper W guided to the paper discharge unit 40 by the switching mechanism 43 is conveyed to the paper discharge table 41 by the paper discharge roller 42, and the print surface printed immediately before being transferred to the paper discharge table 41 is faced down. Loaded.

  The reversing unit 50 reverses the printing paper W, and the reversing unit 51 conveys the printing paper W from the circulation conveyance path CR to the reversing table 51 or conveys the printing paper W from the reversing table 51 onto the circulation conveyance path CR. A roller 52 is provided.

  The printing paper W guided to the reversing unit 50 by the switching mechanism 43 is transported from the circulation transport path CR to the reversing table 51 by the reversing roller 52, and is transported from the reversing table 51 to the circulation transport path CR after a predetermined time. Thus, the front and back are reversed with respect to the circulation conveyance path CR. Then, the printing paper W whose front and back sides are reversed is conveyed on the circulation conveyance path CR by a plurality of rollers such as the conveyance roller 53 provided on the circulation conveyance path CR, and is abutted against the secondary paper feeding unit 14. As a result, the printing paper W is slackened, and the slackness adjusts the position of the leading edge of the printing paper W and corrects the skew feeding. Thereafter, the printing paper W is conveyed on the circulation conveyance path CR toward the printing unit 30 at a predetermined timing. .

  In addition, a switching mechanism 44 is provided in the circulation conveyance path CR. When post-processing of the printing paper W is performed, the switching mechanism 44 switches the conveyance direction, so that the printing paper W is turned into the paper reversing device 4. To be guided to. That is, when post-processing from single-sided printing is designated, the printing paper W is discharged from the image forming apparatus 2 by the switching mechanism 44 after printing on one side by the printing unit 30 and is post-processed from double-sided printing. Is designated by the switching mechanism 44 after the printing unit 30 prints the other side (back side) after the printing paper on which one side (front side) is printed is reversed by the reversing unit 50. 2 is discharged to the reversing device 4.

  The sheet reversing device 4 is provided with a reversing unit 401 for reversing the front and back of the printing paper, a driving roller 402 that is rotationally driven provided at the entrance / exit of the reversing unit 401, and a driving roller 402 that is in pressure contact with the entrance / exit of the reversing unit 401. A first driven roller 403 that transports the printing paper W transported on the entrance transport path MR1 to the reversing unit 401, and an exit / entrance of the reversing unit 401 are provided in pressure contact with the driving roller 402, and transported from the reversing unit 401 to the exit And a second driven roller 404 that conveys the printing paper W to the path MR2. The configuration of the sheet reversing device 4 will be described later.

  The post-processing device 3 includes a paper folding processing unit 110. When the printing paper W is folded, the switching mechanism 112 switches the transport direction so that the printing paper W is transferred to the paper folding processing unit 110. Led.

  The printing paper W guided to the paper folding processing unit 110 on the post-processing path FR is subjected to paper folding such as bi-folding, tri-folding, and Z-folding. The paper is discharged to the folding tray 111.

  On the other hand, when paper folding is not performed, the printing paper W is not guided to the paper folding processing unit 110 but is supplied to the punch processing unit 120 on the post-processing path FR, and the paper folding processing unit 110 performs Z folding. Even when the printing is performed, the printing paper W is transported from the paper folding processing unit 110 along the post-processing path FR and supplied to the punch processing unit 120.

  In the punch processing unit 120, punch processing for punching punch holes in the printing paper W according to a print job is executed, and the punch processing unit 120 is conveyed in the direction of the top tray 101, the stacker tray 102, or the stacker tray 103 on the post-processing path FR. The

  The printing paper W transported in the direction of the top tray 101 is stacked on the top tray 101, and the printing paper W transported in the direction of the stacker tray 102 is moved to the position of long-side binding or short-side binding by the staple processing unit 130. In response, the stapling process is performed, and then the stacking process is performed on the stacker tray 102. The printing paper W transported in the direction of the stacker tray 103 is stacked on the stacker tray 103 after the saddle stitching processing unit 140 performs a saddle stitching (center folding) process.

  FIG. 2 is a configuration diagram showing the configuration of the sheet reversing device 4 provided in the image forming system according to the embodiment of the present invention.

  As shown in FIG. 2, the paper reversing device 4 is supplied with the printing paper W discharged outside the apparatus by operating the switching unit 44 of the image forming apparatus 2. The supplied printing paper W is transported by the transport roller 405 to the entrance transport path MR1.

  The transport roller 405 is mechanically connected to a drive motor (not shown) serving as a drive source, and a drive roller 405a that rotates by driving of the drive motor, and a driven roller 405b that rotates by being in pressure contact with the drive roller 405a. The driving roller 405a and the driven roller 405b are pressed against each other and rotated to convey the printing paper W to the entrance conveyance path MR1.

  The entrance conveyance path MR1 is connected to a reversing unit 401 that reverses the front and back of the printing paper W. A driving roller 402 and a first driven roller 403 are provided at the entrance / exit 401c of the reversing unit 401.

  The drive roller 402 is mechanically connected to a drive motor (not shown) serving as a drive source, and is rotationally driven in the J direction by the drive motor.

  The first driven roller 403 is provided in pressure contact with the driving roller 402, and reverses the printing paper W conveyed on the inlet conveying path MR1 by being driven as the driving roller 402 rotates in the J direction. To the unit 401.

  The reversing unit 401 is connected to the printing paper from the reversing unit 401 by the carry-in guide 401 a that guides the loaded printing paper W by the driving roller 402 and the first driven roller 403, and by the driving roller 402 and the second driven roller 404. An unloading guide 401b for guiding W to unload.

  The carry-in guide 401a is provided with an inclination of about 30 ° with respect to the vertical direction so that the doorway 401c faces downward. In addition, the inclination angle (here, 30 °) of the carry-in guide 401a with respect to the vertical direction is referred to as an approach angle.

  The carry-out guide 401b is provided in a substantially vertical direction so that the doorway 401c faces downward. The inclination angle of the carry-out guide 401b with respect to the vertical direction is referred to as a discharge angle (here, 0 °).

  The second driven roller 404 is provided in pressure contact with the driving roller 402, and is driven as the driving roller 402 rotates in the J direction, so that the printing paper W guided by the carry-out guide 401b is discharged to the exit conveyance path. Transport to MR2.

  The reversing unit 401 is provided with an abutting plate 410 for abutting the printing paper W conveyed along the carry-in guide 401a.

  An abutting support member 411 is connected to the abutting plate 410, and a rack gear 411a is provided on the supporting member 411.

  A pulley 412 is rotatably supported in the vicinity of the rack gear 411a, and a gear 413 mounted coaxially with the rotation shaft of the pulley meshes with the rack gear 411a.

  A motor 415 is provided in the vicinity of the pulley 412, and an endless belt 414 is suspended between the pulley 416 attached to the output shaft of the motor 415 and the pulley 412.

  As a result, when the motor 415 is driven to rotate, the pulleys 416 and 412 rotate, the driving force is transmitted to the rack gear 411a and the gear 413, and the support member 411 is moved to move the abutting plate 410 in the F1 direction or the F2 direction. Move up and down.

  In addition, a paper sensor 421 that detects the printing paper W carried in by the driving roller 402 and the first driven roller 403 is provided in the vicinity of the carry-in guide 401 a of the reversing unit 401.

<Functional Configuration of Image Forming System 1>
FIG. 3 is a functional configuration diagram showing a functional configuration of the image forming system 1 according to the embodiment of the present invention.

  As shown in FIG. 3, among these configurations, the image forming apparatus 2 and the post-processing apparatus 3 have been described above, and a description thereof will be omitted.

  The image forming system 1 is connected to a terminal 100 via a network 9.

  The terminal 100 generates image data by executing software, and the generated image data and setting information such as the designation of double-sided printing or single-sided printing and the presence / absence of post-processing as a print job via the network 9 Send to forming system 1. Here, the presence / absence of post-processing is information indicating whether to execute punch processing, stapling processing, or saddle stitching processing, for example.

  The image forming system 1 is connected to the image reading unit 200 and the fax receiving unit 400.

  The image reading unit 200 is provided on the upper part of the image forming apparatus 2 of the image forming system 1. Although not shown, a contact glass on which an original is placed, a cover provided in contact with and away from the contact glass, and contact glass A scanning unit that scans the document placed thereon, a lens that focuses the scanned image, and an image processing unit that processes the focused image are provided.

  Then, the scanning unit scans the original placed on the contact glass for each line, and the image processing unit processes the scanned image, whereby the image forming system 1 reads image data to be printed.

  The fax receiving unit 400 is a device capable of facsimile communication, and supplies image data received by facsimile to the image forming system 1.

  The image forming system 1 includes an image forming device 2, a sheet reversing device 4, a post-processing device 3, and a control device 5.

  The control device 5 includes an operation unit 60, a control unit 70, a network interface unit 80, and an external interface unit 82.

  The operation unit 60 is provided in the upper part of the image forming apparatus 2, and includes a display / input panel 61, a start key for starting reading and printing, a stop key for stopping reading and printing, the number of printed sheets, and the like. Various operation keys such as a numeric keypad (not shown) for input are provided, and operation signals based on user operations are supplied to the control unit 70.

  The display / input panel 61 of the operation unit 60 includes a pressure-sensitive or electrostatic transparent touch panel disposed on the front surface and a liquid crystal display panel (none of which is shown) disposed on the back surface of the touch panel. ing. The user touches the surface of the touch panel directly with his / her finger while looking at the display screen of the liquid crystal display panel, an operation for starting printing, a setting operation for setting whether to perform post-processing, and a sheet Various setting input operations such as a setting operation for setting whether or not to execute the paper reversing process in the reversing device 4 can be performed.

  The network interface unit 80 is a communication interface such as a network card. The network interface unit 80 connects the image forming system 1 to the network 9 to receive image data from the terminal 100 connected to the network 9. Send and receive various signals.

  The external interface unit 82 is a connection interface with the image reading unit 200, and supplies the image data read by the image reading unit 200 and the image data received by facsimile from the fax receiving unit 400 to the control unit 70.

  The control unit 70 performs central control of the image forming system 1. Moreover, the control part 70 is provided with the receiving part 71, the determination part 72, and the apparatus control part 73 on the function.

  The receiving unit 71 receives a print job transmitted from the terminal 100 via the network interface unit 80. The receiving unit 71 receives a print job transmitted from the image reading unit 200 via the external interface unit 82 and a print job received by facsimile from the fax receiving unit 400.

  The determination unit 72 determines whether or not the printing paper W has been carried into the reversing unit 401 based on the detection results by the paper sensors 421 and 422. Specifically, after the paper sensor 422 detects the printing paper W transported to the entrance transport path MR1 by the transport roller 405, the determination unit 72 uses the driving roller 402 and the first driven roller 403 to detect the print paper W. It is determined whether or not the loaded printing paper W is detected.

  The device control unit 73 controls the image forming apparatus 2, the sheet reversing apparatus 4, and the post-processing apparatus 3 based on the print job received by the receiving unit 71. In particular, when the determination unit 72 determines that the printing paper W has been carried into the reversing unit 401, the device control unit 73 controls the motor 415 so that the position of the abutting plate 410 with respect to the reversing unit 401 moves.

<Operation of Image Forming System 1>
4A to 4D are views showing the operation of the image forming system 1 according to the embodiment of the present invention.

  As shown in FIG. 4A, the printing paper W (W1) transported along the entrance transport path MR1 is brought into the carry-in guide 401a by the driving roller 402 and the first driven roller 403 provided at the entrance / exit of the reversing unit 401. Even if the trailing edge of the printing paper W1 passes through the pressure contact of the driving roller 402 and the first driven roller 403, it rises along the carry-in guide 401a at that angle.

  Then, as shown in FIG. 4B, the printing paper W <b> 1 that has risen along the carry-in guide 401 a hits the butting plate 410. In this manner, the printing paper W1 is slackened by abutting against the abutting plate 410, and thereby skew correction is performed. Note that the amount of slackening when contacting the butting plate 410 varies depending on the paper quality (softness).

  Since the carry-in guide 401a is provided with an inclination of about 30 ° with respect to the vertical direction so that the entrance / exit 401c faces downward, the abutting plate 410 has an angle of about 30 ° with respect to the vertical direction. It is hit by. And the printing paper W1 with which the front-end | tip contact | abutted against the butting board 410 turns in a G direction at a rear end.

  Then, as shown in FIG. 4C, the printing paper W swung in the G direction freely falls along the carry-out guide 401 b and reaches the pressure contact between the driving roller 402 and the second driven roller 404.

  At this time, the printing paper W (W2) which is the next printing paper is conveyed along the carry-in guide 401a by the driving roller 402 and the first driven roller 403.

  Then, as shown in FIG. 4D, the printing paper W that has reached the pressure contact between the driving roller 402 and the second driven roller 404 is moved to the exit conveyance path MR2 by the driving roller 402 and the second driven roller 404. Be transported.

  As described above, in the sheet reversing device 4 included in the image forming system 1 according to the embodiment of the present invention, the driving roller 402 that is rotationally driven and the first driven roller 403 that is driven as the driving roller 402 is rotationally driven. In addition, since the printing paper W is carried in and out by the second driven roller 404, two printing papers W can be present in the reversing unit 401 with a simple configuration. High productivity can be achieved as compared with the case where the paper is reversed.

  FIG. 5 is a diagram showing a result of an experiment in which a paper passing experiment is performed by the image forming system 1 according to the embodiment of the present invention. In the experiment shown in FIG. 5, there are four types of printing paper W, “postcard”, “plain paper”, “thick paper”, and “thin paper”, and the entry angles are “20 °”, “30 °”, “40”, respectively. “°”, the position of the abutting plate 410, “5 (mm)”, “10 (mm)”, “15 (mm)”, “20 (mm)”, “25 (mm)”, the conveyance speed, The paper passing state when “120 (ppm)”, “150 (ppm)”, and “180 (ppm)” was observed. For three types of printing paper, “plain paper”, “thick paper”, and “thin paper”, the paper passing state was observed with the printing sizes set to “A4 size” and “A3” size.

  Here, the position L of the butting plate 410 is a length represented by the following (Equation 1).

L = LT−LW (Equation 1)
L: position of the abutting plate 410 LT: path length along which the printing paper W is conveyed from the pressure contact point of the driving roller 402 and the second driven roller 404 to the position of the abutting plate 410 LW: in the conveying direction of the printing paper W Length In the diagram shown in FIG. 5, the result of the 50-sheet passing experiment is “○” when all printing sheets are properly passed, and the result of the 50-sheet passing experiment is that even one sheet is appropriate. The case where no paper is passed through is indicated as “x”, and as a result of an experiment of 50 paper passing, even when one paper jam (paper jam) occurs appropriately, it is indicated as “jam”.

  As shown in FIG. 5, when the printing paper W is “plain paper” and the printing size is “A3 size”, the approach angle is “20 °” regardless of the position of the abutting plate 410 and the transport speed. It can be seen that paper jam often occurs.

  On the other hand, even when the printing paper W is “plain paper” and the printing size is “A3 size”, if the entrance angle is set to “30 °” or more, the occurrence rate of paper jam is reduced and the paper can be passed appropriately. Will increase.

  This is because if the approach angle is small, the slack generated by the preceding printing paper W hitting the butting plate 410 is too large, and paper jam occurs due to contact with the subsequent printing paper W.

  In addition, even when the position L of the abutting plate 410 is increased, it can be seen that the abutting plate 410 is appropriately conveyed as the conveying speed increases.

  Thus, the printing paper W can be appropriately conveyed by setting the appropriate position L of the abutting plate 410 according to the conveyance speed of the printing paper W.

  Therefore, when the determination unit 72 determines that the printing paper W has been carried into the reversing unit 401, the device control unit 73 of the control unit 70 moves the motor 415 so that the position of the abutting plate 410 with respect to the reversing unit 401 moves. Control. For example, based on the experimental result shown in FIG. 5, the position is stored in advance as a position calculation table in which the position L of the abutting plate 410 that can be appropriately conveyed is associated with the conveyance speed. And the apparatus control part 73 calculates the conveyance speed of the printing paper W carried in from the detection result by the paper sensors 421 and 422, and based on a position calculation table, it can convey appropriately. The position L of the abutting plate 410 is extracted.

  And the apparatus control part 73 controls the motor 415 so that it may become the position L of the extracted butting plate 410. FIG.

  Further, as shown in FIG. 5, when the print size is “A3 size”, if the print paper W is “plain paper”, paper jam often occurs when the entry angle is “20 °”. On the other hand, if the printing paper W is “thick paper” or “thin paper”, the position L of the abutting plate 410 is “10 (mm)” even if the approach angle is “20 °”. You can pass through.

  This is because when the printing paper W is “plain paper”, the slack caused by the preceding printing paper W hitting the abutting plate 410 is too large, and a paper jam occurs due to contact with the subsequent printing paper W. When the printing paper W is “thick paper”, the slack caused by the preceding printing paper W hitting the abutting plate 410 is relatively small, and no paper jam occurs due to contact with the subsequent printing paper W. It depends.

  Further, when the printing paper W is “thin paper”, the slack caused by the preceding printing paper W hitting the butting plate 410 is large, but the printing paper W itself is soft even if it contacts the subsequent printing paper W. Therefore, paper jam does not occur.

  As described above, when the approach angle is “30 °” or more, regardless of the type of the printing paper W and the conveyance speed, it is possible to appropriately pass the paper by appropriately setting the position of the butting plate 410.

  Further, since the discharge angle of the carry-out guide 401b is “0 °”, the abutted printing paper W freely falls and is driven by the driving roller 402 and the second driven roller 404 provided immediately below the abutting. , Transported to the exit transport path MR2.

  As described above, according to the image forming system 1 according to the embodiment of the present invention, the driving roller 402 that is rotationally driven, and the first driven roller 403 and the second driven roller 403 that are driven as the driving roller 402 is rotationally driven. And a reversing unit 401 that reverses the front and back of the printing paper W carried from the entrance 401c and guides it to the entrance 401c. Is provided so as to be inclined with respect to the vertical direction so that the entrance / exit 401c is directed downward, and a carry-in guide 401a for guiding the printing paper W carried by the driving roller 402 and the first driven roller 403 into the reversing unit 401. The inlet / outlet port 401c is provided in a substantially vertical direction so as to face downward, and the printing roller W is counteracted by the driving roller 402 and the second driven roller 404. Because and a discharge guide 401b to induce so as to discharge the section 401 outside, can be a simple device configuration, so the printed printing paper W quickly appropriately inverted. Furthermore, since the printing paper that has passed through the reversing device is turned upside down and ejected with the printing surface printed immediately before facing down, if the user has instructed single-sided printing, the printing order of the print data is changed. There is no need to rearrange them, and the printing process may be performed in ascending order in the order received. Therefore, high productivity can be exhibited even for a print job in which post-processing after single-sided printing is instructed.

  In the embodiment of the present invention, the image forming system 1 including the image forming apparatus 2, the sheet reversing apparatus 4, the post-processing apparatus 3, and the control apparatus 5 has been described as an example. Not limited to this, the image forming apparatus 2, the sheet reversing apparatus 4, and the post-processing apparatus 3 may each be provided with a control device.

  In one embodiment of the present invention, the image forming apparatus 2, the paper reversing device 4, the post-processing device 3, and the control device 5 are provided. The control device 5 includes the image forming device 2, the paper reversing device 4, and the rear device. The image forming system 1 that controls the processing device 3 has been described as an example. However, the present invention is not limited thereto, and the image forming device 2, the sheet reversing device 4, and the post-processing device 3 are each provided with three control devices. You may do it.

DESCRIPTION OF SYMBOLS 1 ... Image forming system 2 ... Image forming apparatus 3 ... Post-processing apparatus 4 ... Paper inversion apparatus 5 ... Control apparatus 60 ... Operation part 70 ... Control part 71 ... Reception part 72 ... Determination part 73 ... Equipment control part 401 ... Inversion part 401a ... carry-in guide 401b ... carry-out guide 401c ... entrance / exit 402 ... drive roller 403 ... first driven roller 404 ... second driven roller 405 ... transport roller 405a ... drive roller 405b ... driven roller 410 ... abutting plate 411 ... support member 412 ... pulley 413 ... gear 414 ... belt 415 ... motor 416, 412 ... pulley 421, 422 ... paper sensor

Claims (5)

Reversing means provided so that the entrance for entering and exiting the printing paper faces downward, and reversing the front and back of the printing paper carried in from the entrance and guiding it to the entrance;
A conveying means provided in the vicinity of the inlet / outlet for carrying the printing paper into the reversing means and carrying out the printing paper reversed by the reversing means from the reversing means;
A sheet reversing device comprising: The inversion means is
A carry-in guide that is provided to be inclined with respect to the vertical direction so that the doorway is directed downward, and guides the printing paper carried by the carrying unit into the reversing unit;
2. A carry-out guide that is provided in a substantially vertical direction so that the entrance / exit is directed downward, and that guides the print sheet to be carried out of the reversing unit by the transport unit. Paper reversing device. A paper stopping means arranged at a position where the leading edge of the printing paper carried by the conveying means is abutted;
The sheet reversing device according to claim 1, further comprising: Paper detection means for detecting the printing paper carried in by the transport means;
Position moving means for moving the position of the paper stopping means relative to the reversing means;
Control means for controlling the position moving means so that the position of the paper stopping means relative to the reversing means moves based on the detection result detected by the paper detecting means;
The sheet reversing device according to claim 3, further comprising: The conveying means is
A driving roller that is rotationally driven in the vicinity of the entrance;
A first driven roller that is provided in pressure contact with the drive roller in the vicinity of the entrance and exits the reversing unit by being driven by the rotation of the drive roller;
A second driven roller which is provided in pressure contact with the drive roller in the vicinity of the entrance and exits the printing paper from the reversing means by being driven by the rotational drive of the drive roller;
The sheet reversing device according to claim 1, wherein the sheet reversing device is provided.

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