JP2008094584A - Sheet stacking device and image forming device equipped with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet stacking device capable of stacking and storing sheets in order on a tray member elevating and lowering vertically and taking out large number of sheets stacked on the tray without causing the collapse of outward form of piled-up sheets. <P>SOLUTION: This sheet stacking device is provided with the tray means on which sheets from a delivery port are stacked, a tray elevating means for lifting and lowering the tray means vertically below the delivery port, a sheet side aligning means arranged above the tray means to regulate a side fringe of the sheet to be carried out of the delivery port in the direction crossing the direction of sheet conveyance orthogonally, and a control means for controlling the tray elevating means for lowering the tray means below the delivery port to take the sheet out of the tray means to the outside. The sheet side aligning means can move freely between an aligning position for engaging it with the side fringe of the sheet on the tray means and an evacuation position for evacuating it from the side fringe of the sheet. When the tray means is lowered by the control means, the sheet side aligning means moves to the evacuation position for evacuating it from the side fringe of the sheet. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet stacking apparatus for stacking and storing sheets sequentially delivered from an image forming apparatus and the like on a tray unit from a sheet discharge port. The present invention relates to an improvement of a tray lifting / lowering mechanism in which sheets on a tray do not cause load collapse when transported to a tray.

  In general, this type of sheet stacking apparatus is widely known as an apparatus for stacking and storing sheets carried out from an image forming apparatus such as a printing machine or a copying machine on a tray unit disposed below a sheet discharge port. An apparatus for accumulating large-capacity sheets that are continuously carried out moves the tray means up and down according to the stacking amount. When the tray is full or when the job is finished, the user takes out the sheet from the tray.

As described above, when a sheet is taken out from the tray, a large-capacity sheet is transported by being transferred to, for example, a carriage, etc., and for example, Patent Document 1 proposes facilitating the transfer operation. In this document, a tray and a lift mechanism that raises and lowers the tray are separated, and sheets are stacked in a pallet shape. At the time of taking out the sheet, a carriage is positioned and set under the lift mechanism, and the tray lowered by the lift mechanism is placed on the carriage. A device that is transferred up and carried out of the device is disclosed. For this reason, in the publication, a tray and an elevating mechanism (elevator mechanism) are provided at a position protruding outward from the apparatus housing, and the carriage is positioned and set below the tray on which sheets are stacked, and the tray is lowered onto the carriage. Are automatically transferred to the cart. As a result, the sheets on the tray can be transported to the outside without being transferred to a transport device such as a carriage.
JP 2000-143070 A

  As described above, when stacking and storing sheets in the tray disposed at the sheet discharge port, if the sheets are carried out at a high speed and the tray is lowered according to the stacking amount to stack a large amount of sheets, the following problem occurs. . In order to stack high-capacity sheets at a high speed on the tray in an orderly manner, the sheet must be unloaded while it reaches the tray from the discharge port. For this reason, this type of apparatus is provided with sheet conveying means such as a vacuum belt and a grip belt for reliably conveying the sheet from the sheet discharge outlet to the front end of the tray. At the same time, sheet side aligning means for restricting the side edge of the sheet conveyed by the sheet conveying means to a predetermined position is provided. The side aligning means is composed of a guide plate that engages with a sheet side edge set in advance according to the sheet size or an aligning plate that is movable in the conveyance orthogonal direction, and the width direction posture of the sheet from the sheet discharge port is constant. It regulates to become.

When taking out the sheet described on the tray with such a configuration, the user lowers the tray and takes out the sheet with his / her fingers, or the tray is transferred to the transporting carriage as in Patent Document 1 described above. Are being transported. In any of the methods, when taking out the sheets that are neatly stacked on the tray, the sheet bundle may touch the above-described aligning means (side edge guide plate or side edge aligning plate), for example, to cause load collapse. . In particular, when a large capacity sheet loaded on a tray is transported out of the apparatus, if the transport carriage is pulled out vigorously, the sheet bundle loaded on this will collide with the aligning means and cause load collapse. There is.
For this reason, conventionally, the maximum load capacity to be loaded on the tray is set small, the tray member is lowered sufficiently downward from the sheet discharge port, and a large space is provided between the uppermost sheet and the sheet conveying means or the alignment member on the sheet side edge. It is formed so that the sheet does not hit these members when the sheet is taken out. For this reason, it has been unavoidable to increase the size of the apparatus or to set the maximum load capacity to be small.

SUMMARY OF THE INVENTION The main object of the present invention is to provide a sheet stacking apparatus capable of orderly loading and storing sheets on a tray member that moves up and down, and simultaneously taking out a large capacity sheet stacked on the tray without collapsing. .
Furthermore, the present invention provides a sheet stacking apparatus capable of transporting sheets in an orderly manner without causing the sheets to collapse when the sheets stacked on the tray are carried out of the apparatus by a carrier such as a transport carriage. It is an issue.

  In order to achieve the above object, the invention of claim 1 employs the following configuration. A sheet discharge port for sequentially carrying out the sheets, a tray unit for stacking sheets from the sheet discharge port, a tray lifting unit for moving the tray unit up and down below the sheet discharge port, and an upper part of the tray unit And sheet side alignment means for regulating the side edges in the direction perpendicular to the conveyance of the sheet carried out from the paper discharge outlet, and the tray means is lowered below the paper discharge outlet to take out the sheet on the tray means to the outside. The tray lifting and lowering control means, and the sheet side alignment means are configured to be movable between an alignment position that engages with the sheet side edge on the tray means and a retreat position that is retracted from the sheet side edge, When the tray means is lowered by the control means, the sheet side aligning means moves to a retracted position retracted from the sheet side edge.

  Further, in the above configuration, the sheet side aligning unit is configured by a pair of front and rear aligning members that regulate both side edges of the sheet from the sheet discharge port, and the pair of aligning members includes at least a sheet on the tray unit. The alignment member located on the side to be taken out moves to the retracted position when the tray means is lowered.

  Next, in order to achieve the above object, the invention of claim 3 employs the following configuration. A sheet discharge port for sequentially carrying out sheets, a tray unit for stacking sheets from the sheet discharge port, and a tray lifting unit for detachably mounting the tray unit and holding it vertically up and down below the sheet discharge port And a sheet conveying means for conveying the sheet from the sheet discharge outlet to the downstream side, and a position above the tray means. A sheet side aligning unit that regulates a side edge in a direction perpendicular to the conveyance of the sheet conveyed by the sheet conveying unit, a control unit that moves the tray lifting unit up and down, and a tray unit that is separated from the tray lifting unit. And carrier means for carrying out of the apparatus. The tray lifting means and the carrier means are constructed so that the tray means can be handed over to each other at the attachment / detachment position where the tray lifting means is lowered, and the sheet side alignment means is engaged with the sheet side edge on the tray means. The control means is configured to be movable between an alignment position to be joined and a retracted position retracted from the sheet side edge, and the control means is retracted from the sheet side edge when the tray means is in the attachment / detachment position. Control to be in position.

  Further, the sheet side aligning means includes a pair of front and rear aligning members that regulate both side edges of the sheet from the sheet discharge port, and the retreat positions of the pair of aligning members are the sheet side edges in the sheet conveyance orthogonal direction, respectively. The alignment member located at a position apart from the tray and at least on the side from which the sheet on the tray means is taken out is set to a position where the alignment member swings and retracts above the tray. Further, when the tray means is lowered, the sheet side aligning means moves from the operating position to the retracted position in conjunction with the lowering operation of the tray lifting / lowering means.

  The seat side aligning means includes a driving means that moves between the operating position and the retracted position. The driving means is either (1) a control signal for lowering the tray elevating means, or (2) the attaching / detaching position. The above-mentioned seat side aligning means by a signal of either the detection sensor of the carrier means positioned and set, or (3) a detection sensor for detecting the opening operation of the door for positioning the carrier means at the attachment / detachment position Is moved from the operating position to the retracted position.

  The sheet side aligning means is composed of a pair of front and rear aligning members that regulate both side edges of the sheet from the paper discharge port, and the carrier means is configured to transfer the tray means from the attachment / detachment position to the outside of the apparatus. The tray means is carried out from the front side of the pair of front and rear alignment members, and the alignment member located on the front side is configured to be retracted above the tray means.

  The sheet side aligning means includes a pair of front and rear aligning members that respectively regulate both side edges of the sheet from the sheet discharge port, and the aligning member aligns and aligns the sheet side edges carried out from the sheet discharge port. Thus, it is configured to reciprocate in the conveyance orthogonal direction. The sheet stacking apparatus includes an image forming apparatus that sequentially forms images on sheets, a sheet discharge unit that guides sheets from the image forming apparatus to a sheet discharge port, and a tray that stacks and stores sheets from the sheet discharge port. Means.

  The present invention is provided with sheet side aligning means for restricting the side edge in the direction perpendicular to the conveyance when the sheet is carried out to the tray means arranged to be movable up and down below the sheet discharge port, and this aligning means when the tray means is lowered. Is retracted from the side edge of the seat. For this reason, when taking out the sheets stacked on the tray, the sheet side alignment means such as the guide plate and alignment member arranged above the tray move to the retracted position retracted from the side edge of the sheet. The sheet on the tray can be easily taken out without causing it. Accordingly, the maximum stacking amount of sheets stacked on the tray can be set to the maximum without providing a dead space below the sheet discharge port, and the vertical height of the apparatus can be configured to be small and compact.

  Further, by adopting a configuration in which the tray is configured in a pallet shape, separated from the tray lifting mechanism and transferred to a carrier means such as a transportation carriage, the sheet can be easily removed. With such a configuration, the present invention prevents the sheets loaded on the tray from colliding with the aligning means when the sheets loaded on the tray are vigorously carried out of the apparatus by the carriage.

  The present invention will be described in detail below based on the preferred embodiments shown in the drawings. FIG. 1 is an overall view of an image forming system provided with a sheet stacking apparatus according to the present invention, and FIG. 2 is a configuration diagram of a main part of the sheet stacking apparatus.

[Image forming system]
The image forming system shown in FIG. 1 includes an image forming apparatus A and a sheet stacking apparatus B, and the sheet stacking apparatus B is configured to stack and store sheets formed with the image forming apparatus A on a tray of the sheet stacking apparatus B. It is connected to the paper discharge port 3 of the image forming apparatus A. Hereinafter, the image forming apparatus A and the sheet stacking apparatus B will be described in this order.

[Image forming apparatus]
First, an example of an image forming apparatus for forming an image on a sheet is shown in FIG. 1 and will be described. The image forming apparatus A shown in FIG. 1 sends a sheet from the paper supply unit 1 to the image forming unit 2, prints the sheet on the image forming unit 2, and then carries the sheet out from the paper discharge port 3. The sheet feeding unit 1 stores sheets of a plurality of sizes in sheet feeding cassettes 1 a and 1 b, and separates designated sheets one by one and feeds them to the image forming unit 2. The image forming means 2 includes, for example, an electrostatic drum 4, a print head (laser light emitting device) 5 and a developing device 6 arranged around the electrostatic drum 4, a transfer charger 7, and a fixing device 8. An electrostatic latent image is formed by the light emitting device 5, toner is adhered to the developing device 6, an image is transferred onto the sheet by the transfer charger 7, and heat fixing is performed by the fixing device 8. The sheets on which images are formed in this manner are sequentially carried out from the paper discharge port 3 (hereinafter referred to as “main body discharge port”). 9 is a circulation path, which is a double-sided printing path in which a sheet printed on the front surface from the fixing device 8 is reversed and fed again to the image forming unit 2 and printed on the back surface of the sheet. The sheet printed on both sides in this way is turned upside down by the switchback path 10 and then carried out from the main body discharge port 3.

  11 is an image reading apparatus, which scans a document sheet set on a platen 12 with a scanning unit 13 and electrically reads it with a photoelectric conversion element (not shown). The image data is digitally processed by an image processing unit, for example, and then transferred to the data storage unit 14 to send an image signal to the laser emitter 5. 15 is a document feeder, which is a feeder device that feeds a document sheet stored in the document stacker 16 to the platen 12.

[Sheet Accumulator]
Next, the sheet stacking apparatus B will be described. The illustrated sheet stacking apparatus B includes a sheet carry-in path 21, a tray unit 25, a sheet conveying unit 28, and a sheet leading end regulating unit 33 arranged in a suitably shaped housing 20 (see FIG. 1). Then, the sheet is sent from the sheet carry-in path 21 to the sheet discharge port 23, the sheet is conveyed to the front end side of the tray by the sheet conveying unit 28, and the sheet is abutted against the sheet leading end regulating unit 33 and separated from the sheet conveying unit 28. The tray means 25 is dropped and stored.

[Sheet carry-in route]
The sheet carry-in path 21 includes a conveyance guide having a sheet receiving port 22 and a sheet discharge port 23, and a sheet discharge unit 24 that conveys the sheet is provided in the sheet carry-in path 21. As shown in FIG. 2, the paper discharge unit 24 includes a driving roller 24 a and a driven belt 24 b (may be a driven roller), and carries a sheet from the receiving port 22 to a paper discharge port 23. The paper discharge means 24 is provided with a blower means F having an air jet port (not shown), and simultaneously cools the sheet in the path and simultaneously sends the sheet from the paper discharge outlet 23 to the sheet conveying means 28 described later by the air flow. It comes to lead. S1 in the drawing is a paper discharge sensor for detecting the leading edge and the trailing edge of the sheet.

[Sheet conveying means]
A sheet conveying means 28 is provided above the downstream side of the paper discharge port 23. The sheet conveying means 28 is constituted by a grip belt or a vacuum belt for nipping the sheet, and conveys the sheet from the sheet discharge port 23 to the front end side of the tray by nip or suction. This is because when the sheet from the sheet discharge port 23 is directly carried out onto the tray, it comes into contact with the sheet on the tray and causes a sheet discharge failure (jam), and the sheet discharge speed is limited by the frictional resistance of the sheet. Accordingly, the sheet conveying means 28 transports the sheet from the paper discharge port 23 to the front end of the tray at the same speed as the speed at which the paper discharge means 24 carries it out, and the sheets are dropped and accumulated while the entire sheet is moved onto the tray. It is. Therefore, the sheet conveying means 28 is constituted by a vacuum belt that sucks the sheet or a grip belt that nips the leading end of the sheet.

  The structure of the latter grip belt will be described. A pair of pulleys 29a and 29b are provided on the apparatus frame 26 above a tray means 25 described later, and a belt member 30 is stretched between the pulleys. The belt member 30 is provided with a gripper member 27. The gripper member 27 has a nip piece 27a that engages with the front end of the sheet so as to grasp the front end of the sheet from the discharge outlet 23 and guide it to a predetermined unloading position Ep (see FIG. 2). The belt member 30 is integrally provided so as to move at the same speed as the other sheet. A driving motor M1 is connected to the pulley 29a of the belt member 30 so as to rotate clockwise in FIG. Accordingly, when the belt member 30 is stopped with the gripper member 27 facing the paper discharge port 23 and the sheet is carried out from the paper discharge port 23, the leading end of the sheet enters between the nip piece 27a and the belt surface, and the nip piece 27a The leading edge of the sheet is gripped by the elastic force.

[Sheet tip regulating means]
At the carry-out position Ep of the sheet conveying means 28, a sheet leading edge regulating means 33 is provided. This regulating means 33 is arranged above the tray means alongside the belt member 30. A stopper piece 35 is provided to abut against the leading edge of the sheet transported by the belt member 30 and separate the sheet from the conveying means 28. A plurality of the stopper pieces 35 are arranged in the sheet width direction (conveying orthogonal direction), and are configured to move forward and backward in the conveying direction according to the sheet size as shown in FIG. That is, the sheet front end restricting means 33 (hereinafter referred to as “stopper unit”) is supported by the apparatus frame 26 on a guide rail (not shown) so as to be movable back and forth in the conveying direction (left and right direction in FIG. 2). The stopper unit 33 is connected to a position adjustment belt (endless belt or the like) stretched in the left-right direction in FIG. 2, and this belt is moved by the position adjustment motor M2 (not shown) in the left-right direction in FIG. It has become.

  The illustrated stopper piece 35 is provided with a first stopper piece 35a and a second stopper piece 35b with a distance in the front and rear directions in the transport direction, and the second stopper piece 35b adjacent to the paper discharge port 23 is swingable in the vertical direction in FIG. The shaft is supported and moved up and down by a drive motor (not shown). This is because the front and rear positions are shifted on the tray means 25 for offset storage in order to align the sheets from the paper discharge port 23 (jog sorting). The illustrated Sp1 is a paper surface level detection sensor, and its operation will be described later.

[Seat side alignment means]
As described above, the sheet from the sheet discharge outlet 23 is conveyed to the tray leading end side by the sheet conveying unit 28, is peeled off from the sheet conveying unit 28 by the sheet leading end regulating unit 33 and falls onto the tray unit 25. In this process, the sheet is aligned in the conveying orthogonal direction by the sheet side aligning means (alignment member) 54 and is stored in alignment on the tray. For this reason, sheet side alignment means 54 including alignment members 54a and 54b is provided on the side edges (around FIG. 2) of the sheet conveyed by the sheet conveyance means 28. As shown in FIG. 2, the rear side alignment member 54b for regulating the sheet side edge on the back side of the apparatus and the front side alignment member 54a for regulating the sheet side edge on the front side of the apparatus are arranged from above the tray means 25 downward as shown in FIG. It is arranged to hang down. Both the alignment members 54a and 54b (hereinafter collectively referred to as “alignment member 54”) are supported by the shaft member 54c and moved in the left-right direction in FIG. 3A.

  The illustrated alignment member 54 is movable to an engagement position X (see FIG. 3A) for engaging with the sheet side edge, a standby position Y slightly separated from the sheet side edge, and a retracted position Z sufficiently separated from the sheet side edge. The shaft member 54c is fitted and supported. The alignment member 54 is connected to a pair of left and right shift levers 56a and 56b connected to the width adjusting motor M4, and both levers are engaged with a pinion M4p of the width adjusting motor M4. Accordingly, the alignment member 54 moves in accordance with the width size of the sheet by the rotation of the pinion M4p. That is, the front side / rear side alignment members 54a and 54b are moved to a position suitable for the sheet width size by the rotation of the width adjusting motor M4, and at this position, the standby position Y slightly separated from the sheet side edge and the sheet side edge are engaged. The reciprocating motion is caused by forward / reverse rotation of the pinion M4p with the engaging position (operating position) X. Further, the aligning member 54 is moved by the width adjusting motor M4 to the retracted position Z sufficiently separated from the sheet side edge.

  Simultaneously with the movement to the retracted position Z by the rotation of the width adjusting motor M4, the front-side alignment member 54a is such that the leading-end hanging piece 54a 'hanging down toward the tray means 25 is bent to the solid line position at the retracted position indicated by Z in FIG. It has become. The structure is such that the tip depending piece 54a 'is pivotally supported at the base end portion and is urged to a solid line state shown in FIG. 3A by a spring (not shown) at the engagement position X and the standby position Y. A cam piece 55a is provided on the tip depending piece 54a ', and a protruding lever 55b formed on the apparatus frame 26 abuts against the cam piece 55a. Therefore, when the leading end hanging piece 54a 'of the front side alignment member 54a moves from the standby position Y to the retracted position Z, the cam piece 55a hits the protruding lever 55b of the apparatus frame and bends to the state shown in the solid line in the figure. Thus, the retracted positions Z of the pair of alignment members 54 are positions spaced apart from the sheet side edges in the sheet conveyance orthogonal direction and at least the front side alignment members 54a positioned on the side where the sheets on the tray means 25 are taken out to the outside. Swings and retreats above the tray. Therefore, when the tray means 25 is taken out together with the stacked sheets to the front side of the apparatus, the front side alignment member 54a is retracted above the tray.

  Note that the above-mentioned front side alignment member 54a may have a structure shown in FIG. 3B. A solid line is shown by connecting an electromagnetic solenoid 57 to a tip drooping piece 54a 'pivotally supported on the front side alignment member 54a and suspending the tip drooping piece 54a' against the biasing spring by the electromagnetic solenoid 57. It can be moved to the retreat position. The electromagnetic solenoid 57 is operated by an instruction signal for lowering a tray lifting / lowering means 31 (described later) to an attachment / detachment position (lowermost position), for example.

  Next, control of the above-mentioned width adjusting motor M4 will be described. The width adjusting motor M4 constitutes drive means for moving the alignment member 54 between the engagement position (actuation position) X and the retracted position Z. This drive means lowers the tray elevating means 31 described later (1). Or (2) the detection sensor S3 of the carrier means 40 positioned and set at the tray attaching / detaching position, or (3) the opening / closing doors 50a and 50b for positioning the carrier means 40 at the tray attaching / detaching position. The seat side aligning means 54 is configured to move from the engagement position (actuation position) X to the retracted position Z by any signal of a detection sensor (door opening / closing sensor S5 described later).

[Sheet rear edge pressing means]
A sheet trailing edge pressing means 58 is provided for striking the trailing edge of the sheet toward the tray in the process of dropping the sheet onto the tray means 25 together with the sheet side alignment means 54. As shown in FIG. 4, the sheet trailing edge pressing means 58 is disposed on the downstream upper side of the sheet discharge outlet 23, and a flat plate-like hitting piece 58a that strikes the sheet trailing edge from the sheet discharge outlet 23 on the lower tray means 25. It has. The hit piece 58 a is inserted into a support cylinder 59 fixed to the apparatus frame 26 and connected to the drive lever 60. A drive motor M5 is connected to the drive lever 60, and the drive lever 60 swings at a predetermined angle by forward and reverse rotation of the drive motor M5. The hitting piece 58a connected to the drive lever 60 is between the solid line and the chain line in FIG. It will move up and down. Accordingly, the sheet that is peeled off from the sheet conveying means 28 by the sheet leading edge regulating means 33 and dropped onto the tray means 25 is tapped down by the tapping piece 58a and stored in the tray.

[Configuration of tray means]
The tray means 25 is composed of a paper platform (hereinafter referred to as “tray 25”) on which sheets are stacked, and is configured to be capable of placing a maximum size sheet in a substantially horizontal posture. The illustrated tray 25 is composed of a tray member separated from the apparatus frame 26 so that it can be transported to the outside of the apparatus in the form of a pallet, and is detachably mounted on the tray lifting / lowering means 31 described below.

[Tray lifting means]
As shown in FIG. 5, the tray lifting / lowering means 31 for mounting the tray 25 is composed of fork-like lifting arms 31a and 31b (fork members; the same applies hereinafter) mounted on the apparatus frame 26 so as to be movable up and down. The elevating arms 31a and 31b are guided in the stacking direction (vertical direction in FIG. 5) along the guide rails 32a and 32b provided on the apparatus frame 26, and are supported so as to be movable up and down. The elevating arms 31 a and 31 b are suspended by a pulling member 37 such as a wire or belt that is stretched over a suspension pulley 36 fixed to the apparatus frame 26, and the illustrated pulling wire is connected to a take-up pulley 38. A lifting motor M3 is connected to the winding pulley 38. Accordingly, the lifting arms 31a and 31b are supported by the guide rails 32a and 32b of the apparatus frame 26 and are moved up and down by the lifting motor M3. The tray 25 is mounted on the lifting arms 31a and 31b, and is moved up and down according to the stacking amount below the paper discharge port 23.

  The elevating arms 31a and 31b are provided with a rear end regulating member for regulating the rear end of the sheet, and the rear end of the sheet from the sheet discharge port 23 is abutted on the tray 25 mounted on the elevating arms 31a and 31b. Then, they are stacked one after another. The elevating arms 31a and 31b support the tray means 25 so that it can be moved up and down below the sheet discharge port 23, and can be raised and lowered between the sheet storage position and a tray attaching / detaching position set further below. ing. The tray attaching / detaching position is not limited to the lowermost position of the tray lifting / lowering means, but is set to an appropriate position for taking out the sheet from the tray means to the outside of the apparatus below the sheet storage position. The tray is carried out to the outside of the apparatus.

[Paper holding means]
The tray 25 mounted on the tray lifting / lowering means 31 is provided with a paper pressing means 61 for pressing and supporting the stacked sheets. The sheets stacked on the tray 25 are provided with a pair of left and right paper pressing members 61a and 61b (hereinafter collectively referred to as “paper pressing members 61”) that press and support the sheet side edges orthogonal to the paper discharge direction. The pressing member 61 is retracted from the tray when the sheet falls, and presses the uppermost sheet after the sheet is dropped and stored. For this reason, the illustrated paper pressing member 61 includes an arm-shaped paper touch piece 62 a and a cylinder cam 62 b, and the cylinder cam 62 b is fixed to the apparatus frame 26. The cylinder cam 62b is formed with an inclined cam groove 62c for rotating the paper touch piece 62a according to the vertical movement. The paper touch piece 62a is provided with a pin 62d that is fitted to the cylinder cam 62b and engages with the inclined cam groove, and an arm 63 connected to the vertical movement motor M6 is fitted to the paper touch piece 62a. Accordingly, when the motor M6 is driven in the direction of the arrow in FIG. 6C, the arm 63 pulls the paper touch piece 62a upward. At this time, the pin 62d of the paper touch piece 62a is rotated approximately 90 degrees by the inclined cam groove 62c of the cylinder cam 62b, and at the same time the paper touch piece 62a moves upward from the state of FIG. Move to the retreat position by swinging 90 degrees. Spa shown in the drawing is a position sensor for the paper touch piece 62a, and the position is detected with the retracted position as the home position.

[Tray lifting control]
The tray elevating means 31 is provided with an upper limit position sensor Sp2 for detecting an upper limit position, a maximum stacking position sensor Sp3 for detecting a maximum stacking position, and a lower limit position sensor Sp4 for detecting a lower limit position. The control means 70 of the lifting motor M3, which will be described later, moves the lifting arms 31a and 31b up and down by rotationally driving the lifting motor M3 with the detection signal of the paper level sensor Sp1 and each sensor. Details of the operation will be described later.

[Installation structure]
The installation structure of the lifting arms 31a and 31b will be described with reference to FIG. 7. The guide rails 32a and 32b are fixedly supported by an installation frame 39 that supports the housing 20 and the apparatus frame 26. This installation frame 39 is formed of a U-shaped frame, and the front side of the apparatus, the front side of FIG. 1 (the left front side of FIG. 7) is opened, and a pair of left and right side frames 39a and 39b are connected by a connecting frame 39c on the back side. Fixed and configured. A carrier means (transport cart) 40, which will be described later, can be carried in from the front side of the apparatus. The pair of left and right side frames 39a and 39b are provided with casters 39d to support the overall weight of the sheet stacking apparatus B. The installation frame 39 is provided with a carrier means connecting portion to be described later and a stopper means for preventing the carrier means from being connected.

[Career means]
Next, the carrier means 40 will be described with reference to FIG. 8. The tray 25 is detachably mounted on a tray lifting / lowering means (elevating / lowering arm) 31 and is mounted on the carrier means 40 installed below the tray lifting / lowering means 31. 25 is taken over and carried out of the apparatus. Therefore, the carrier means 40 includes a carriage frame 41 and an operation handle 42 fixed to the carriage frame 41. The carriage frame 41 is configured in a U shape by integrally fixing a pair of left and right fork-like arm members 41a and 41b (fork members; hereinafter the same) and a connecting arm 41c. An operating handle 42 for pushing is fixed to the connecting arm 41c, and wheels 43 are attached to the left and right arm members 41. Accordingly, by manually pressing the operation handle 42, the tray 25 on which the sheets are stacked can be mounted on the arm members 41a and 41b and transported.

[Carrier means positioning set]
The arm members 41 a and 41 b of the carrier means 40 are guided between the pair of left and right side frames 39 a and 39 b of the installation frame 39 and guided into the housing 20. That is, the outer dimension L1 of the arm members 41a and 41b substantially coincides with the inner dimension L2 of the side frames 39a and 39b on the apparatus frame side (L1 = L2), and is guided between the side frames and enters the apparatus housing 20. It is like that. Accordingly, the side frames 39 a and 39 b of the installation frame 39 constitute a guide member for guiding the carrier means 40 into the housing 20. The left and right arms 41a and 41b are formed so that the former is wide (L3) and the latter is narrow (L4) so that the elevating arms 31a and 31b are located inside, and L3> L4.

  Therefore, a positioning recess (positioning member) 44 is provided in the connecting frame 39c of the installation frame 39, and a protrusion (not shown) formed on the arm member 41 of the carrier means 40 is fitted. A magnet catch 44a is embedded in the positioning recess 44, and at the same time, a detection sensor S3 including a magnetic sensor (lead sensor) is built in the catch. Accordingly, the carrier means 40 is guided by the side frames 39a and 39b of the installation frame 39, and is positioned by being fitted into the positioning recess 44, and is held by the magnet catch 44a. Then, it is detected whether or not the carrier means 40 is mounted at a predetermined position by the detection sensor S3, and the lifting arm 31 positioned above is lowered.

The sheet discharge operation in the above-described apparatus will be described. For example, the control unit 70 of the sheet stacking apparatus B drives and rotates the sheet discharge unit 24 when receiving a discharge instruction signal from the image forming apparatus A, for example. . Then, the sheet from the main body discharge port 3 of the image forming apparatus A is guided to the sheet carry-in path 21. At this time, since the sheet conveying means 28 is waiting at a position where the gripper member 27 faces the paper discharge port 23, the leading edge of the sheet is sandwiched between the nip pieces 27a and held by the belt member 30 by its elasticity. When the sheet conveying means 28 is constituted by a vacuum belt, it is sucked and held by this belt.
Next, the control unit 70 rotates and drives the sheet conveying unit 28 at the same speed as that of the sheet discharging unit 24 to convey the sheet to the tray leading end side. When the leading edge of the sheet fed by the sheet conveying means 28 abuts against the stopper piece 33a of the sheet leading edge regulating means 33, the sheet is peeled off from the belt member 30, and at this time, the trailing edge of the sheet is carried out from the paper discharge port 23 to the tray side. Because of this, the sheet falls “sheet dropping operation”. Therefore, when the control means 60 moves the alignment members 54a, 54b of the sheet side alignment means 54, which has been waiting in the standby position Y in advance, to the engagement position (actuation position) X, the sheet is hit by the alignment members 54a, 54b at the side edges. "Sheet width direction alignment" that is aligned and aligned.

  The control means 70 rotates the drive motor M5 of the sheet trailing edge pressing means 58 and swings the drive lever 60 in the clockwise direction in FIG. 4 before and after the alignment of the alignment members 54a and 54b. Then, the “sheet pressing operation” in which the hitting piece 58a vigorously hits the rear end of the sheet downward. Prior to this operation, the control means 70 has moved the paper contact piece 62a of the paper pressing means 61 to the retracted position. This movement to the retracted position is a “paper pressing member retracting operation” in which the paper touch piece 62a is moved to the retracted position in FIG.

  Therefore, the sheet from the sheet discharge port 23 is conveyed to the front end of the tray by the sheet conveying means 28, is separated from the conveying means and falls to the tray side. At this time, the posture in the width direction is forcibly dropped by the hitting piece 58a. . Next, the control means 70 operates the vertical movement motor M6 at the timing when the sheet is stored on the tray, and returns the paper touch piece 62 at the retracted position to the operating position for pressing the sheet on the tray.

  By repeating the above-described operation, the sheets sent to the paper discharge outlet 23 are stacked and stored on the tray 25. When the above-mentioned paper level detection sensor Sp1 detects a predetermined amount of sheet stacking, the control means 70 moves down the lifting arm 31 by a certain amount. When the lifting arm 31 is lowered to the position of the maximum loading amount set in advance, the control means 70 determines that it is full. When this fullness is detected or in response to a job end signal from the image forming apparatus A, the control unit 70 activates the width adjusting motor M4 to move the sheet side alignment unit 54 to the retreat position Z described above. Then, the rear side alignment member 54b is retracted to a position sufficiently away from the sheet side edge, and the front side alignment member 54a is sufficiently separated from the sheet side edge, and the leading end hanging piece 54a ′ at the lower end thereof swings upwards of the tray. Then retreat. For this reason, when the sheet on the tray is taken out, there is no possibility that the upper layer sheet hits the front-side alignment member 54a and the load collapses.

[Tray lifting operation]
Next, the operation of handing over the tray means 25 between the carrier means 40 and the tray lifting / lowering means 31 will be described. The housing 20 is provided with opening / closing doors 50a, 50b on the front side of the apparatus (front side in FIG. 1), and a door opening / closing sensor S5 is provided on the opening / closing door. Therefore, the control means 70 for controlling the lift motor M3 raises the tray 25 mounted on the lift arms 31a and 31b to a position where the paper surface level detection sensor Sp1 detects by the initialization operation when the apparatus power is turned on. Then, the lift arms 31a and 31b are lowered by a predetermined amount by the detection signal of the paper surface level detection sensor Sp1. Then, a preset step D (see FIG. 9A) is formed between the paper discharge outlet 23 and the tray 25, and sheets from the paper discharge outlet 23 are stacked and stored on the tray.
When a predetermined amount of sheets are stacked on the tray, the paper level detection sensor Sp1 detects this, and the control means 70 rotates the elevating motor M3 so as to lower the elevating arms 31a and 31b by a predetermined amount. In this way, when sheets are stacked on the tray and the stacking amount reaches a predetermined amount, the control means 70 lowers the lifting arms 31a and 31b by a predetermined amount by a signal from the paper surface level detection sensor Sp1, and according to the sheet stacking amount. Gradually descend. When the elevating arms 31a and 31b reach the maximum loading position, the maximum loading position sensor Sp3 detects this, and at the same time as issuing a “full detection signal”, the apparatus is stopped.

  Next, when the user opens the open / close doors 50a and 50b by the full detection signal or the job end signal, the control means 70 detects this by the door open / close sensor S5 and safely stops the apparatus. In this state, the elevating arms 31a and 31b are held at the full position or above the positions. When the user enters the carrier means 40 into the apparatus, the carriage frame 41 of the carrier means 40 is guided into the apparatus by guiding the arm members 41a and 41b to the side frames 39a and 39b of the installation frame 39. When a protrusion (not shown) of the carrier means 40 is fitted into the positioning recess 44, the detection sensor S3 detects this. The control means 70 descends the lifting arm 31 toward the attachment / detachment position by a signal from the detection sensor S3, and stops the lifting motor M3 when the lower limit position sensor Sp4 is "ON". At this time, the elevating arms 31a and 31b transfer the tray 25 to the arm members 41a and 41b of the carriage frame 41 in the state shown in FIG.

  As described above, according to the present invention, the sheet side aligning means that regulates and aligns the side edges of the sheets stacked on the tray is retracted to the retracted position away from the sheet side edges when the tray is lowered to take out the sheets. When the user takes out the sheet from the tray or when the tray is transferred to the carrier means 40 for transportation, the load does not collapse.

1 is an overall view of an image forming system including a sheet stacking apparatus according to the present invention. The principal part block diagram of a sheet | seat stacking apparatus. FIG. 6 is an operation explanatory diagram of sheet size matching means. An embodiment different from FIG. 3A is shown. The operation | movement explanatory drawing of a sheet rear end pressing means. The structure explanatory view of tray raising and lowering means. 4A and 4B are explanatory diagrams of a paper pressing unit, in which FIG. 4A shows a state in which a sheet side edge is pressed and supported, FIG. 4B shows a state in a retracted position (home position), and FIG. Indicates. The installation structure of a tray raising / lowering means is shown. The whole perspective view of a carrier means. (A) (b) It is explanatory drawing of raising / lowering operation | movement of a tray means, and shows the state which a tray means stacks | stacks a sheet | seat.

Explanation of symbols

A Image forming apparatus B Sheet stacking apparatus 20 Housing 21 Sheet carry-in path 23 Paper discharge port 24 Paper discharge means 25 Tray means 28 Sheet conveying means 31 Tray elevating means 31a Elevating arm 31b Elevating arm 33 Sheet leading edge regulating means (stopper unit)
39 Installation frame 40 Carrier means 41a Arm member 41b Arm member 54 Sheet side aligning means 54a Front side aligning member 54a 'leading end hanging piece 54b Rear side aligning member 58 Sheet rear end pressing means 58a Tapping piece 60 Drive lever 61 Paper pressing means 61a Paper Presser member 61b Paper presser member 62a Paper contact piece 62b Cylinder cam 62c Inclined cam groove 62d Pin 70 Control means M3 Lifting motor M4 Width adjusting motor M4p Pinion M5 Drive motor M6 Vertical motion motor S3 Detection sensor S5 Door open / close sensor Spa Position sensor Sp1 Paper surface Level detection sensor

Claims (8)

A paper discharge port for sequentially carrying out the sheets;
Tray means for stacking sheets from the discharge port;
Tray elevating means for elevating and lowering the tray means below the discharge port;
A sheet-side alignment unit that is disposed above the tray unit and regulates a side edge in a direction perpendicular to the conveyance direction of the sheet carried out from the discharge port;
Control means for the tray lifting and lowering means for lowering the tray means below the paper discharge port for taking out the sheet on the tray means to the outside;
The sheet side alignment means is configured to be movable between an alignment position that engages with a sheet side edge on the tray means, and a retracted position that is retracted from the sheet side edge,
When the control unit lowers the tray unit, the sheet side aligning unit moves to a retracted position retracted from the sheet side edge. The sheet side alignment means is composed of a pair of front and rear alignment members that regulate both side edges of the sheet from the sheet discharge outlet,
2. The sheet according to claim 1, wherein the pair of aligning members move to a retracted position when an aligning member positioned at least on a side where the sheet on the tray unit is taken out is lowered. Integrated device. A paper discharge port for sequentially carrying out the sheets;
Tray means for stacking sheets from the discharge port;
A tray lifting and lowering means for detachably mounting the tray means and holding the tray means so as to be movable up and down below the discharge port;
A sheet conveying means disposed above the tray means for conveying the sheet from the sheet discharge outlet to the downstream side;
A sheet side aligning unit that regulates a side edge in a conveyance orthogonal direction of a sheet that is disposed above the tray unit and is transferred by the sheet conveying unit;
Control means for raising and lowering the tray elevating means;
Carrier means for carrying the tray means separated from the tray lifting means and carrying it outside the apparatus;
With
The tray elevating means and the carrier means are configured to take over and attach the tray means to each other at an attaching / detaching position where the tray elevating means is lowered.
The sheet side alignment means is configured to be movable between an alignment position that engages with a sheet side edge on the tray means, and a retracted position that is retracted from the sheet side edge,
The sheet stacking apparatus according to claim 1, wherein the control unit controls the sheet side aligning unit to be in a retracted position retracted from a sheet side edge when the tray unit is in the attachment / detachment position. The sheet side alignment means is composed of a pair of front and rear alignment members that regulate both side edges of the sheet from the sheet discharge outlet,
The retraction positions of the pair of alignment members are positions separated from the sheet side edge in the sheet conveyance orthogonal direction, and at least the alignment member located on the side where the sheet on the tray unit is taken out is swinged and retracted above the tray. The sheet stacking apparatus according to claim 1, wherein the sheet stacking apparatus is set to a position where the sheet stacking is performed. The seat side aligning means includes a driving means that moves between the operating position and the retracted position. The driving means is either (1) a control signal for lowering the tray elevating means, or (2) the attaching / detaching position. The above-mentioned seat side aligning means by a signal of either the detection sensor of the carrier means positioned and set, or (3) a detection sensor for detecting the opening operation of the door for positioning the carrier means at the attachment / detachment position The sheet stacking apparatus according to claim 3, wherein the sheet stacking apparatus is moved from the operating position to the retracted position. The sheet side aligning means is composed of a pair of front and rear aligning members that restrict both side edges of the sheet from the discharge port from the front side and the rear side of the apparatus,
When the carrier means transports the tray means from the attachment / detachment position to the outside of the apparatus, the carrier means carries out the tray means from the apparatus front side of the pair of front and rear alignment members,
4. The sheet accumulating apparatus according to claim 3, wherein the aligning member positioned on the front side of the apparatus is configured to retract above the tray means. The sheet side alignment means is composed of a pair of front and rear alignment members that regulate both side edges of the sheet from the sheet discharge outlet,
7. The alignment member according to claim 1, wherein the alignment member is configured to reciprocate in a direction perpendicular to the conveyance so as to align the side edges of the sheet conveyed from the sheet discharge port. The sheet stacking apparatus according to claim 1. An image forming apparatus for sequentially forming images on sheets;
A paper discharge unit for guiding the sheet from the image forming apparatus to a paper discharge port;
A tray stacking unit for stacking and storing sheets from the sheet discharge port;
Consisting of
An image forming apparatus comprising the sheet stacking apparatus according to any one of claims 1 to 7.

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