JP4408705B2 - Post-processing apparatus and image forming apparatus - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a post-processing apparatus that performs post-processing such as stapling on a sheet bundle on which images have been formed, and an image forming apparatus such as a copying machine, a printer, a facsimile apparatus, and a multifunction machine including these post-processing apparatuses. is there.

  Conventionally, a post-processing device is connected to or built in an image forming apparatus such as a copying machine, and a plurality of printed sheets (copy paper, OHP film, etc.) are stacked and stacked on a post-processing tray, A technique for performing post-processing such as sort processing is widely known.

  In such a post-processing apparatus, the sheet is arranged so that alignment work, which is pre-processing of post-processing, can be performed smoothly, and problems such as paper folding, wrinkling, and tearing do not occur in the thick sheet bundle after the post-processing. It is necessary to smoothly feed the bundle to a sheet discharge tray or the like outside the apparatus, and various techniques for that purpose have been developed.

  For example, in the technique disclosed in Patent Document 1, as shown in FIG. 9, a sheet discharge roller pair 100 includes a discharge lower roller 101 and a discharge upper roller 102, and both rollers 101 and 102 come into contact with each other to form a nip P. And a retracted position where the rollers 101 and 102 are separated from each other to form a gap that allows the sheet bundle to pass therethrough.

  Such a conventional post-processing device 103 presses both rollers 101 and 102 together with the spring force of the coil spring 104 at the set position. Further, in such a conventional post-processing apparatus 103, a solenoid 105 and a lever 106 constitute a guide drive means 107, and the discharge upper guide 108 that rotatably supports the discharge upper roller 102 by the guide drive means 107 is coiled. The spring 104 is rotated against the spring force.

JP 2002-167115 A

  However, in the prior art disclosed in Patent Document 1, since the spring force of the coil spring 104 becomes a resistance force to move the discharge upper roller 102 to the retracted position, the guide driving means 107 (particularly, the solenoid) 105) has a large load and power consumption.

  Further, in the prior art disclosed in Patent Document 1, the guide driving means 107 must separate the discharge lower roller 101 and the discharge upper roller 102 against the spring force of the coil spring 104. In the balance between the operating force of the coil spring 104 and the spring force of the coil spring 104, the setting of the spring force of the coil spring 104 must be limited, and the nip force between the discharge lower roller 101 and the discharge upper roller 102 (both rollers 101, 102) The contact force at the nip portion) could not be set independently (regardless of the operating force of the guide driving means 107).

  Therefore, the present invention provides a technique that can reduce the load acting on the guide driving means when the sheet discharge roller pair moves, and can freely set the nip force of the sheet discharge roller pair according to the sheet conveyance conditions. The purpose is to do.

The invention according to claim 1 is a sheet in which a plurality of sheets are stacked on a post-processing tray, the post-processing is performed on the plurality of sheet bundles, and then the sheet bundle is arranged in a discharge path from the post-processing tray. The present invention relates to a post-processing apparatus that discharges the discharge path to the outside by a discharge roller pair . Among these, the sheet discharge roller pair is (1) a discharge lower roller supported rotatably on the apparatus main body side, and (2) a longitudinal intermediate portion is rotatably supported on the apparatus main body side, A discharge lower guide for guiding the movement of the sheet bundle; and (3) a longitudinal intermediate portion is rotatably supported on the apparatus main body side, and the sheet bundle guided and moved by the discharge lower guide is passed therethrough. An upper discharge guide; and (4) pivotally supported on one end of the upper discharge guide and brought into contact with the lower discharge roller by the upper discharge guide to form a nip or away from the lower discharge roller. And an upper discharge roller . The upper discharge guide is biased by the first guide driving means in a direction in which one end side presses the upper discharge roller against the lower discharge roller, and the other end side separates the upper discharge roller from the lower discharge roller. It is urged in the direction by the second guide driving means. The first guide driving means can release the urging force to the upper discharge guide and rotate the upper discharge guide when the second guide driving means rotates the upper discharge guide. To. Further, the second guide driving means stops operating when the first guide driving means urges the upper discharge guide to rotate, thereby enabling the upper discharge guide to rotate. The lower discharge guide is: (1) At a set position where a nip is formed by the lower discharge roller and the upper discharge roller, one end on the lower discharge roller side is more than the upper discharge roller with respect to the nip. (2) the upper discharge guide is rotated by a predetermined amount by the second guide driving means, and the upper discharge roller is separated from the lower discharge roller by a predetermined amount; It is rotated together with the discharge upper guide by the second guide driving means, and one end side thereof is positioned on the discharge upper roller side with respect to the outer surface on the discharge upper roller side of the discharge lower roller, and the sheet is the lower discharge roller. so as not to contact the, so as to guide the movement of the sheet bundle.

  According to a second aspect of the present invention, there is provided an image forming unit that forms an image on a sheet, and a post-processing apparatus according to the first aspect of the invention that performs post-processing on the image-formed sheet. The present invention relates to an image forming apparatus.

  According to the present invention, when the upper discharge roller is separated from the lower discharge roller, the biasing force of the first guide driving means for pressing the upper discharge roller against the lower discharge roller is released. The load acting on the guide driving means can be reduced. Therefore, when the second guide driving means is composed of an electric actuator, it is possible to reduce power consumption. In addition, according to the present invention, the urging force of the first guide driving means can be set independently and freely so as to meet the sheet conveyance conditions regardless of the urging force of the second guide driving means.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Schematic configuration of post-processing apparatus and image forming apparatus including the same>
FIG. 1 shows a schematic configuration of a post-processing apparatus 1 and an image forming apparatus 2 having the same according to an embodiment of the present invention.

  As shown in FIG. 1, a sheet (copy paper, OHP film, etc.) 4 sent out from the paper feed tray 3 is printed with an image forming unit 5, and then a discharge roller pair on the image forming apparatus main body 6 side. 7 is sent to the sheet conveyance path 8 of the post-processing apparatus 1. In addition, since the punching operation to the sheet 4 in the post-processing is performed by the punch unit 9 set in the sheet conveyance path 8, the following post-processing is, for convenience of explanation, a stapler processing excluding the punching operation, etc. It shall be said.

  The sheet 4 sent to the sheet conveyance path 8 of the post-processing apparatus 1 is guided to the sheet discharge roller pair 12 via the discharge path 11 by the branching claw 10 when not post-processed, and discharged by the sheet discharge roller pair 12. It is sent out on the tray 13.

  Further, the sheet 4 sent to the sheet conveyance path 8 of the post-processing apparatus 1 is sent onto the post-processing tray 15 via the post-processing conveyance path 14 by the branching claw 10 when post-processing.

  A plurality of sheets 4 stacked on the post-processing tray 15 are aligned by the aligning means 16 that slides along the post-processing tray 15, and then post-processing such as staple processing is performed by the post-processing means 17 such as a stapler. Applied.

  The post-processed sheet bundle is conveyed toward the sheet discharge roller pair 12 by a sheet receiving member 18 that slides on the post-processing tray 15.

  The sheet discharge roller pair 12 is configured to send the sheet bundle that has been subjected to post-processing onto the sheet discharge tray 13.

<Configuration of sheet discharge roller pair>
2 to 5 are diagrams showing the configuration of the sheet discharge roller pair 12 and the driving means thereof according to the embodiment of the present invention, and are the configuration diagrams of the portion indicated by K in FIG.

  As shown in these drawings, the sheet discharge roller pair 12 is rotated on the discharge upper guide 21 supported at the apparatus main body 20 so that the middle portion in the longitudinal direction is rotatable, and on the one end 21 a side of the discharge upper guide 21. A discharge upper roller 22 supported so as to be able to rotate, a discharge lower guide 23 supported so that the middle portion in the longitudinal direction can be rotated on the apparatus main body 20 side, and a discharge lower roller 24 supported so as to be rotatable on the apparatus main body 20 side. And. A plurality of the sheet discharge rollers 12 are arranged at appropriate intervals in the sheet passing width direction (direction orthogonal to the sheet discharge direction), and any size sheet to be subjected to post-processing of the post-processing apparatus 1 can be used. It can be surely transported (see particularly FIGS. 3 and 4).

  Among these, the discharge lower guide 23 is rotatably supported by the frame 26 on the apparatus main body 20 side by a support pin 25 at its longitudinal intermediate portion. However, the discharge lower guide 23 is configured such that a rotational moment in the counterclockwise direction is generated with respect to the rotation fulcrum (support pin 25) by its own weight. The lower discharge guide 23 is such that one end 23a on the lower discharge roller 24 side is retracted from the outer peripheral surface of the lower discharge roller 24 at the set position where the lower discharge roller 24 and the upper discharge roller 22 form a nip P. In order to be positioned, the locking member 27 formed on the frame 26 on the apparatus main body 20 side is supported via a cushioning material 28 (see particularly FIG. 5). That is, the rotation of the lower discharge guide 23 due to its own weight is prevented by the locking member 27 on the apparatus main body 20 side.

  Further, a substantially U-shaped groove (U-shaped groove 30) that opens toward the tip is formed on the other end 23 b side of the lower discharge guide 23. The U-shaped groove 30 is configured to engage with a connecting pin 31 as a protrusion formed on the other end 21b side of the discharge upper guide 21 described later with a gap. Here, the gap amount between the connecting pin 31 and the U-shaped groove 30 is configured to produce a maximum separation dimension between the discharge upper roller 22 and the discharge lower roller 24 as described later. The lower discharge guide 23 guides the movement of the sheet by the sheet guide plate portion 23c.

  The upper middle portion of the discharge upper guide 21 is rotatably supported by a support pin 25 common to the lower discharge guide 23. The upper discharge guide 21 is biased by the first guide driving means 32 in a direction in which one end 21a side presses the upper discharge roller 22 against the lower discharge roller 24, and the other end 21b side discharges the upper discharge roller 22 from the lower discharge roller. It is urged by the second guide driving means 33 in the direction away from the second guide driving means 33. The upper discharge guide 21 is attached on the other end 21b side so that a connecting pin 31 that engages with the U-shaped groove 30 of the lower discharge guide 23 with a gap protrudes from the side surface. The upper discharge guide 21 has a long hole 34 that engages with the support pin 25 so that it can be rotated counterclockwise with the nip P between the upper discharge roller 22 and the lower discharge roller 24 as a rotation fulcrum. It has become.

  The first guide driving means 32 is rotatable via a support pin 39 to a first solenoid (first electric actuator) 35 attached to a frame (not shown) on the apparatus main body 20 side and a frame 26 on the apparatus main body 20 side. The lever 36 is supported, and a tension spring 38 that connects one end 36 a of the lever 36 and the operation rod 37 of the first solenoid 35. The first guide driving means 32 is turned on (energized) when the second solenoid 40 of the second guide driving means 33 is turned off (not energized), and rotates the lever 36 clockwise via the tension spring 38. The other end (tip) 36b of the lever 36 presses the one end 21a side of the discharge upper guide 21. As a result, the upper discharge guide 21 presses the upper discharge roller 22 against the lower discharge roller 24 and forms a nip P at the contact portion between the upper discharge roller 22 and the lower discharge roller 24.

  On the other hand, the first solenoid 35 of the first guide driving means 32 is turned off (non-energized) when the second solenoid 40 of the second guide driving means 33 is turned on (energized), and the discharge upper guide 21 is rotated in the clockwise direction. The load is not applied during rotation.

  As a result, the load acting on the second solenoid 40 of the second guide driving means 33 is reduced and the second solenoid 40 is excited compared to the conventional example (see FIG. 9) in which the spring force of the coil spring 104 always acts. Less power consumption. Further, the first guide driving means 32 urges the force that urges the discharge upper roller 22 toward the discharge lower roller 24, and the second guide drive means 33 urges the discharge upper roller 22 away from the discharge lower roller 24. Regardless of the force, it can be set independently and freely so as to meet the sheet conveyance conditions.

  The second guide driving means 33 is rotatably supported by a second solenoid (second electric actuator) 40 attached to the frame 26 on the apparatus main body 20 side, and a support pin 41 on the frame 26 on the apparatus main body 20 side. And a connection ring 44 such as a wire for connecting the one end 42 a of the lever 42 and the operation rod 43 of the second solenoid 40. In the second guide driving means 33, when the second solenoid 40 is turned on (energized), the lever 42 is pulled by the operation rod 43 of the second solenoid 40, and the lever 42 is rotated in the clockwise direction. The other end (front end) 42b of the lever 42 pushes the other end 21b side of the discharge upper guide 21 to rotate the discharge upper guide 21 around the support pin 25 (clockwise direction). In this embodiment, instead of the connection ring 44, a connection pin (not shown) may be engaged with the hole 45 of the operation rod 43 and the hole 46 of the lever 42.

  A sheet detection sensor 47 is disposed in the vicinity of the nip P between the discharge upper roller 22 and the discharge lower roller 24. In addition to detecting the jam by the sheet detection sensor 47, as described later, the sheet front end is detected by the sheet detection sensor 47. And the operation timing of the first solenoid 35 and the second solenoid 40 is controlled based on the detection signal.

  According to the present embodiment configured as described above, when a sheet that is not subjected to post-processing is discharged onto the sheet discharge tray 13 by the sheet discharge roller pair 12, the first solenoid 35 is energized and the tension spring 38 is energized. The top end 36b of the lever 36 is pressed against the upper surface of the one end 21a of the discharge upper guide 21 by the spring force, and the upper discharge roller 22 is pressed against the lower discharge roller 24 via the upper discharge guide 21. At this time, the second solenoid 40 is turned off (non-energized), and the upper discharge guide 21 is rotated by the first guide driving means 32. As a result, a nip P is formed at the contact portion between the lower discharge roller 24 and the upper discharge roller 22, and the sheet is sent out onto the paper discharge tray 13 by the sheet discharge roller pair 12 (see FIGS. 1 and 6).

  When the post-processed sheet bundle is discharged onto the sheet discharge tray 13 by the sheet discharge roller pair 12, the power supply to the first solenoid 35 is turned off, and the discharge upper guide 21 is rotated counterclockwise. The second solenoid 40 is energized almost simultaneously with the release of the biasing spring force, and the second solenoid 40 rotates the lever 42 in the clockwise direction. The upper surface on the end 21b side is pressed, and the discharge upper guide 21 is rotated clockwise around the support pin 25 as the rotation center. As a result, the upper discharge roller 22 rotatably supported on the one end 21a side of the upper discharge guide 21 is separated from the lower discharge roller 24 (see FIG. 7).

When the upper discharge guide 21 is further rotated in the clockwise direction, the connecting pin 31 attached to the other end 21 b of the upper discharge guide 21 comes into contact with the lower edge 48 of the U-shaped groove 30 of the lower discharge guide 23. The position where the connecting pin 31 contacts the lower edge 48 of the U-shaped groove 30 of the lower discharge guide 23 is the maximum separation position between the upper discharge roller 22 and the lower discharge roller 24. Here, the maximum dimension at which the discharge upper roller 22 is separated from the discharge lower roller 24 is, for example, a sheet bundle in which 50 A4 size copy sheets having a basis weight of about 64 g / m ² are bundled. However, the present invention is not limited to this, and may be appropriately changed according to design conditions and the like. Thereafter, the upper discharge guide 21 and the lower discharge guide 23 are integrally rotated counterclockwise (see FIG. 7).

  The lower discharge guide 23 is separated from the locking member 27 on the apparatus main body 20 side at one end 23a side, and rotates integrally with the upper discharge guide 21 around the support pin 25, and the one end 23a side is discharged. If it rotates to the position which protruded from the outer peripheral surface of the lower roller 24, the action | operation of the 2nd solenoid 40 will be hold | maintained and the attitude | position will be maintained (refer FIG. 8). This position is the retreat position of the discharge upper guide 21 and the discharge upper roller 22.

  Thus, the lower end of the sheet bundle sent out from the post-processing tray 15 by the sheet receiving member 18 by the one end 23a side of the lower discharge guide 23 and the sheet guide plate portion 23c projecting from the outer surface of the lower discharge roller 24. The sheet on the side does not come into contact with the outer surface of the lower discharge roller 24, and the leading end side of the sheet bundle passes smoothly without being caught in the gap between the lower discharge roller 24 and the upper discharge roller 22. When the passage of the leading end of the sheet bundle is detected by the sheet detection sensor 47, the energization of the second solenoid 40 is interrupted, and the first solenoid 35 is energized almost simultaneously with the interruption of the energization of the second solenoid 40. .

  As a result, the pressing force toward the other end 21 b of the discharge upper guide 21 is released, while the one end 21 a side of the discharge upper guide 21 is pressed counterclockwise by the spring force of the tension spring 38. As a result, the post-processed sheet bundle is sandwiched between the lower discharge roller 24 and the upper discharge roller 22, and the sheet bundle is reliably and smoothly sent onto the discharge tray 13 by the lower discharge roller 24 and the upper discharge roller 22.

  The sheet discharge roller pair 12 has a large post-processed sheet size, and discharges the rear end of the sheet (one end that is the front end when discharging the sheet bundle) with the lower discharge roller 24 during the sheet alignment operation on the post-processing tray 15. Even when the upper roller 22 has to protrude beyond the nip P, the upper roller 22 is moved to the retracted position. Thereby, the alignment work of the large-size sheet bundle on the post-processing tray 15 is smoothly performed.

  Moreover, although this Embodiment illustrated the aspect which engages the connection pin 31 of the discharge | emission upper guide 21 with the U-shaped groove 30 of the discharge | emission lower guide 23, a connection pin is attached to the discharge | emission lower guide 23, and this connection pin A U-shaped groove 30 that engages with the discharge upper guide 21 may be formed.

  Further, in the present embodiment, by engaging the connecting pin 31 of the upper discharge guide 21 with the U-shaped groove 30 of the lower discharge guide 23 with a gap, the lower discharge guide 23 is delayed from the rotation of the upper discharge guide 21. However, the present invention is not limited to this, and the lever 42 of the second guide driving means 33 presses the upper discharge guide 21 and then sends the lower discharge guide 23 to press it. The rotating operation of the lower discharge guide 23 may be delayed with respect to the rotating operation of the guide 21.

  Further, the post-processing apparatus 1 of the present embodiment can be applied to either the electrophotographic image forming apparatus 2 or the inkjet image forming apparatus 2.

  The post-processing apparatus of the present invention can be used in combination with an image reading apparatus such as a scanner, and can be used for post-processing a sheet bundle after image reading.

1 is a schematic configuration diagram of a post-processing apparatus according to an embodiment of the present invention and an image forming apparatus including the post-processing apparatus. It is a sheet discharge roller opposite side lineblock diagram of the aftertreatment device concerning an embodiment of the invention. FIG. 3 is an external perspective view of a discharge port side showing a configuration opposite to a sheet discharge roller of the post-processing apparatus according to the embodiment of the present invention. FIG. 3 is an external perspective view of the rear side showing the configuration opposite to the sheet discharge roller of the post-processing apparatus according to the embodiment of the present invention. It is a perspective view which shows the engagement state of the lower discharge guide and the locking member of the apparatus main body side. FIG. 6 is a first state diagram illustrating a configuration of the sheet discharge roller opposite side of the post-processing apparatus in which a frame on the apparatus main body side is omitted. FIG. 6 is a second state diagram illustrating a configuration of the sheet discharge roller opposite side of the post-processing apparatus in which the apparatus main body side frame is omitted. FIG. 10 is a third state diagram illustrating a configuration of the sheet discharge roller opposite side of the post-processing apparatus in which the frame on the apparatus main body side is omitted. It is a sheet | seat discharge roller opposite side block diagram of the post-processing apparatus which concerns on a prior art example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Post-processing apparatus, 2 ... Image forming apparatus, 4 ... Sheet, 5 ... Image forming part, 11 ... Discharge path, 12 ... Sheet discharge roller pair, 15 ... Post-processing tray, 20 ... Main body of the apparatus, 21 ... discharge upper guide, 21a, 23a ... one end, 21b, 23b ... other end, 22 ... discharge upper roller, 23 ... discharge lower guide, 24 ... discharge lower roller, 27 ... engagement Stop member, 32... First guide drive means, 33... Second guide drive means

Claims (2)

A plurality of sheets are stacked on the post-processing tray, and after the post-processing is performed on the plurality of sheet bundles, the sheet bundle is disposed in the discharge path from the post-processing tray by the pair of sheet discharge rollers. In the aftertreatment device that is to be discharged to the outside ,
The sheet discharge roller pair is:
A lower discharge roller supported rotatably on the apparatus main body side;
A lower discharge guide that is supported rotatably on the apparatus body side in the longitudinal direction and guides the movement of the sheet bundle,
A discharge upper guide that passes through the sheet bundle that is supported by the apparatus main body side in a rotatable manner in the longitudinal direction and that is guided and moved by the discharge lower guide;
A discharge upper supported by one end of the upper discharge guide so as to be rotatable, and is brought into contact with the lower discharge roller by the upper discharge guide to form a nip or to be separated from the lower discharge roller. A roller, and
One end of the upper discharge guide is urged by the first guide driving means in a direction to press the upper discharge roller against the lower discharge roller, and the other end is in a direction to separate the upper discharge roller from the lower discharge roller. Urged by the second guide driving means,
The first guide driving means releases the urging force to the discharge upper guide when the second guide drive means rotates the discharge upper guide, and enables the discharge upper guide to rotate.
The second guide driving means stops operation when the first guide driving means urges the upper discharge guide to rotate, and enables the upper discharge guide to rotate.
The lower discharge guide is
In the set position where a nip is formed by the lower discharge roller and the upper discharge roller, one end on the lower discharge roller side is positioned farther to the lower discharge roller side than the upper discharge roller with respect to the nip.
The discharge upper guide is rotated by a predetermined amount by the second guide driving means, and after the discharge upper roller is separated from the discharge lower roller by a predetermined amount, it is rotated by the second guide driving means together with the discharge upper guide. are located on the upper discharge roller side than the outer surface of the discharge on the roller side of the one end the lower discharge rollers, so that the sheet is not in contact with the lower discharge rollers, and guides the movement of the sheet bundle ,
A post-processing device. An image forming apparatus comprising: an image forming unit that forms an image on a sheet; and the post-processing device according to claim 1 that performs post-processing on the image-formed sheet.

Images