JP2012240763A - Paper discharge device and image forming system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a paper arrangement condition when paper is placed on a paper placement table and shorten the time required for paper placement.SOLUTION: A paper discharge device has a paper discharge part that includes a placement surface SS on which paper to be discharged by a paper discharge roller one by one or with two pieces stacked is placed, an abutting part 80c against which a rear end in the paper discharge direction of the paper placed on the placement surface SS is abutted, and a support member 93 and a pressing member 91 that sandwich the paper at a paper sandwiching position and move it to a paper placement position on the placement surface SS. The paper discharge device can perform control so that when paper is discharged by the paper discharge roller with two pieces stacked, both the support member 93 and the pressing member 91 are driven, and when the paper is discharged by the paper discharge roller one by one, at least one of the support member 93 and the pressing member 91 is driven.

Description

  The present invention relates to a paper discharge device and an image forming system.

In general, in an image forming apparatus configured with a post-processing device such as a printer or a copying machine, a plurality of sheets on which an image has been formed is temporarily stored inside the apparatus or discharged outside the apparatus. A paper mounting table such as a paper discharge tray is provided for loading stacked paper.
Conventionally, when the paper is discharged to these paper mounting tables, the stacking position is shifted until the paper falls on the paper mounting table by its own weight, away from the paper transport roller immediately before the paper mounting table. There has been a problem that sheets cannot be stacked with the edges of the sheets aligned on the mounting table.
This problem is likely to occur regardless of whether the mounting surface of the paper mounting table is horizontal or inclined, especially when the paper transport speed is high or when environmental conditions are severe, such as high temperature and high humidity or low temperature and low humidity. It is easy to get up.

  On the other hand, a technique is disclosed in which sheets are stacked in a stacker, the ends of the stacked sheets are held between grippers, and the grippers are moved to be stacked on a discharge tray (for example, Patent Document 1). reference).

JP 2008-273656 A

  However, with the technology described in Patent Document 1, it is difficult to neatly align the ends of the discharged paper, and since the paper is once accumulated in the stacker and the accumulated paper is moved, There was a problem that it took time to load the paper on the paper discharge tray.

  The present invention has been made in view of the above problems, and an object of the present invention is to improve the paper alignment state when the paper is placed on the paper placement table and to shorten the time until the paper is placed. It is an object of the present invention to provide a sheet discharge device and an image forming system capable of performing the above.

To solve the above problem,
The invention according to claim 1 is a paper discharge device,
A paper stacking unit for stacking sheets discharged one by one or two by the discharge means;
An abutting portion that abuts the rear end of the paper stacking direction of the paper loaded on the paper stacking portion;
A sheet discharge unit having a pair of sheet nipping members that nipping the sheet in a state where each sheet or two sheets are stacked at a sheet nipping position and moving the sheet to a sheet stacking position in the sheet stacking unit;
The pair of paper nipping members is
A support member held on the lower side of the paper discharged by the discharge means so as to be rotatable around a rotation axis parallel to the width direction of the paper;
A pressing member held swingably about a rotation axis parallel to the width direction of the paper on the upper side of the paper discharged by the discharging means;
With
When the paper is discharged in a state where two sheets are stacked by the discharge means, both the pressing member and the support member are driven,
A control unit is provided for controlling to drive at least one of the pressing member and the support member when a sheet is discharged one by one by the discharging unit.

According to a second aspect of the present invention, in the paper discharge device according to the first aspect,
A setting unit for performing a setting operation for the user to drive both or one of the pressing member and the support member when the discharge unit discharges the paper one by one;
The control unit drives at least one of the pressing member and the support member in accordance with a setting operation by the setting unit.

According to a third aspect of the present invention, in the paper discharge apparatus according to the first or second aspect,
The support member is
When rotating and moving upstream with respect to the paper discharge direction, the uppermost paper loaded on the paper stacking unit abuts on the uppermost paper and the uppermost paper is placed upstream of the paper discharge direction. A friction member that biases toward the abutting portion is provided.

According to a fourth aspect of the present invention, in the paper discharge device according to the first or second aspect,
The controller is
In the case where the sheet is discharged one by one by the discharging unit, at least one of the pressing member and the support member is driven according to the type of the discharged sheet.

Further, the invention according to claim 5 is the paper discharge device according to any one of claims 1 to 4,
The controller is
According to the present invention, at least one of the pressing member and the support member is driven in accordance with the interval between sheets discharged by the discharging unit.

The invention according to claim 6
In an image forming system comprising: an image forming apparatus that forms an image on a sheet; and a post-processing apparatus that performs post-processing on a sheet on which an image is formed by the image forming apparatus.
Comprising the paper discharge device according to any one of claims 1 to 5,
The post-processing apparatus includes the paper discharge unit.

  ADVANTAGE OF THE INVENTION According to this invention, the paper alignment state at the time of a paper being mounted in a paper mounting base can be improved, and the time until it is mounted can be shortened.

1 is an overall configuration diagram of an image forming system in the present embodiment. It is a block diagram of an intermediate conveyance unit. It is a perspective view showing a paper discharge mechanism and a paper discharge unit. It is a block diagram which shows the control structure of an image forming system. It is sectional drawing in the AA of FIG. 3, Comprising: It is a figure for demonstrating operation | movement of a pressing member and a supporting member. It is sectional drawing in the AA of FIG. 3, Comprising: It is a figure for demonstrating operation | movement of a pressing member and a supporting member. It is sectional drawing in the AA of FIG. 3, Comprising: It is a figure for demonstrating operation | movement of a pressing member and a supporting member.

  Embodiments of the present invention will be described below with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

First, the configuration will be described.
As shown in FIGS. 1 to 4, the image forming system 1000 according to the present embodiment includes a large-capacity paper feeding device A, an image forming device B, a post-processing device C, and a control unit that performs overall control of the entire image forming system 1000. 100.

(Large capacity feeder A)
The large-capacity paper feeding device A includes a paper storage unit 7A, a first paper feeding unit 7B, and the like.
The sheet storage unit 7A stores a large amount of sheets S such as A4 size and A3 size, for example. The paper S stored in the paper storage unit 7A is continuously sent to the image forming apparatus B by the first paper supply unit 7B.

(Image forming apparatus B)
The image forming apparatus B includes an image reading unit 1, an image writing unit 3, an image forming unit 4, a paper feeding / conveying unit 5, a fixing unit 6, an automatic document conveying unit B1, an operation display unit B2, and the like.

  The image reading unit 1 includes a scanner below a contact glass on which an original is placed, and reads an image on a sheet to acquire image data. The scanner is composed of a light source, a CCD (Charge Coupled Device) image sensor, an A / D converter, and the like. The reflected light of the light scanned from the light source to the original is imaged and photoelectrically converted to convert the original image into RGB. The signal read and photoelectrically converted as a signal is sent to the image writing unit 3 after undergoing processing such as A / D conversion, shading correction, and image compression processing.

  In the image writing unit 3, the output light from the semiconductor laser is applied to the photosensitive drum 4A of the image forming unit 4, and an electrostatic latent image is formed on the photosensitive drum 4A.

The image forming unit 4 includes a photosensitive drum 4A, a charging unit 4B, a developing unit 4C, a transfer unit 4D, a separation unit 4E, a cleaning unit 4F, and the like.
In the image forming unit 4, processes such as charging, exposure, development, transfer, separation, and cleaning are performed on the electrostatic latent image formed on the photosensitive drum 4A.

The sheet feeding / conveying unit 5 includes a plurality of sheet feeding cassettes 5A, a first sheet feeding unit 5B, a second sheet feeding unit 5C, a conveying unit 5D, a sheet discharging unit 5E, an automatic duplex copying sheet feeding device (ADU) 5F, and the like. Has been.
In the paper feed cassette 5A, the paper S identified in advance for each paper type (paper type, basis weight, size) is stored. The paper S is one sheet from the top by the first paper feed unit 5B. Each is conveyed toward the second sheet feeding unit 5C.
The second paper feeding unit 5C conveys the paper S conveyed from the paper supply tray to the transfer unit 4D of the image forming unit 4. The sheet S on which the image is transferred by the transfer unit 4D is transported to the fixing unit 6 by the transport unit 5D.

The fixing unit 6 includes a heating roller having a heat source and a pressure roller that presses against the heating roller to form a nip portion, and heat-fixes the toner image transferred to the paper S. The sheet S on which the toner image is fixed by the fixing unit 6 is sent to the post-processing device C from the paper discharge unit 5E.
When images are formed on both sides of the paper S, the front and back sides are reversed by the automatic double-sided copy paper feeder 5F after the paper S is fixed, and sent again to the image forming unit 4 to form an image. It is sent to the processing device C.

  The automatic document feeder B1 feeds the documents placed on the document table one by one and supplies them to the image reading unit 1. A document supplied from the document table of the automatic document feeder B1 to the image reading unit 1 is scanned on one or both sides of the document by the optical system of the image reading unit 1, and the photoelectrically converted signal is A / D converted. After being subjected to processing such as shading correction and image compression processing, it is sent to the image writing unit 3.

The operation display unit B2 includes a touch panel display having an LCD (Liquid Crystal Display), and various setting screens, device status displays, operation states of functions, and the like on the display screen according to instructions of display signals input from the control unit 100. Is displayed.
The touch panel display is configured by covering the LCD display screen with a pressure-sensitive (resistive film pressure) touch panel configured by arranging transparent electrodes in a grid pattern, and is pressed with a finger or a touch pen. The position coordinate is detected by the voltage value.
The operation display unit B2 outputs the detected position signal to the control unit 100 as an operation signal.
The user can input the type of post-processing or the type of paper stored in the paper feed cassette 5A by operating the operation display unit B2.
Further, when the user operates the operation display unit B2 to discharge the sheets one by one by a sheet discharge roller 80a (described later) of the post-processing apparatus C, a pair of sheet nipping members (described later) A setting operation related to driving can be performed.

  Note that the image forming apparatus B in FIG. 1 forms a monochrome image on the paper S, but may form a color image on the paper S.

(Post-processing device C)
The post-processing apparatus C includes an intermediate transport unit C1 that superimposes the sheets S and a post-processing unit C2 that performs post-processing such as binding processing.
In the present embodiment, the intermediate transport unit C1 and the post-processing unit C2 are independent casings, but the intermediate transport unit C1 and the post-processing unit C2 may be the same casing.

(Intermediate transport unit C1)
As shown in FIG. 2, the intermediate transport unit C1 includes a paper carry-in unit 11, a stacking unit 12, a paper carry-out unit 13, a bypass transport unit 14, and the like.

  The paper carry-in unit 11 includes a paper conveyance path r11 having conveyance rollers R1 and R2 and a guide plate 111. In the paper carry-in unit 11, the paper S discharged from the paper discharge unit 5E of the image forming apparatus B is sequentially received and conveyed.

The stacking unit 12 includes two guide plates 121 arranged in parallel, a vertical alignment unit including a stop member 123, a horizontal alignment member 122, a carry-in drive roller R3, a carry-out drive roller R4, and paper. A transport path r12, and the like.
Further, for a specific job that executes a binding process or the like, two sheets S are stacked in the stacking unit 12 and then discharged upward in a stacked state.

  The paper carry-out unit 13 includes an intermediate conveyance roller R5, paper discharge rollers R6a, R6b, R7a, R7b, and a paper conveyance path r13 having a guide plate 131. In the paper carry-out unit 13, the front and back of the stacked paper S stored in the stacking unit 12 are reversed and conveyed to the post-processing unit C <b> 2.

  The bypass transport unit 14 includes a paper transport path r14. The conveyance of the sheet S to the bypass conveyance unit 14 is performed when it is not necessary to convey the sheet S to the stacking unit 12. For example, there is a case where the binding process of the paper S is unnecessary, or a case where the paper S is discharged without being reversed.

In addition, the paper carry-in unit 11 is provided with a conveyance path switching unit G2 that branches the paper to the stacking unit 12 or the bypass conveyance unit 14.
In addition, a conveyance path switching unit G <b> 1 that switches between introducing the paper S into the stacking unit 12 and discharging the paper S from the stacking unit 12 is provided above the stacking unit 12.
The transport path switching units G1 and G2 are each connected to a solenoid and driven.

In this way, the intermediate transport unit C1 can stack two sheets S output from the image forming apparatus B in the stacking unit 12, and the two stacked sheets S (hereinafter referred to as S1 (first sheet) ), S2 (second sheet),...) Are turned upside down and conveyed to the post-processing unit C2.
Further, the paper S that does not require post-processing such as binding processing is transported via the bypass transport unit 14 and the paper discharge transport unit 30 of the post-processing unit C2 without passing through the stacking unit 12, and passes through the paper discharge roller 80a. Then, it is discharged to the liftable sheet discharge tray 80b.

The intermediate transport unit C1 superimposes two sheets S1 and S2 on the stacking unit 12 and transports them to the post-processing unit C2, thereby delaying the time for transporting the paper S to the post-processing unit C2. The post-processing time in the post-processing unit C2 can be secured.
As a result, it is possible to prevent a decrease in productivity of paper output from the image forming apparatus B at high speed.

(Post-processing unit C2)
The post-processing unit C2 includes an inlet transport unit 20, a paper discharge transport unit 30, a connection transport unit 40, an insertion paper feed unit 50, a binding processing unit 60, a stack unit 65, a folding unit 70, a paper discharge mechanism unit 80, In addition, a paper discharge unit 90 and the like are disposed.

  In the entrance transport unit 20, the sheets S discharged from the intermediate transport unit C1 are sequentially received and transported.

  The paper discharge conveyance unit 30 conveys the paper S that does not require post-processing such as binding processing. The paper S conveyed via the paper discharge conveyance unit 30 is discharged to the liftable paper discharge tray 80b via the paper discharge roller 80a.

  The connected transport unit 40 transports the paper S from the entrance transport unit 20 to the stack unit 65. The sheets S transported by the connection transport unit 40 are stacked in the stack unit 65 and the binding processing unit 60 performs the binding process. As a result, a partial booklet composed of a plurality of sheets S is produced.

  The insertion sheet feeding unit 50 feeds a sheet to be inserted into a predetermined position in the binding process. The sheets fed from the insertion sheet feeding unit 50 are stacked in the stack unit 65 via the connection conveyance unit 40.

The binding processing unit 60 executes a binding process using a plurality of sheets S stacked in the stack unit 65 as a part of a booklet.
In the case of one-sided binding in which the staple in the binding process is performed on one side of the sheet bundle, the booklet is discharged to the elevating sheet discharge tray 80b, and in the case of saddle stitching in which the staple in the binding process is performed at the center of the sheet bundle, The sheet is folded halfway at the section 70 and discharged to the sheet discharge tray 82.

  The folding unit 70 folds the booklet when performing saddle stitching in the binding process.

  The post-processing unit C2 in the present embodiment performs a binding process by the binding processing unit 60 on a plurality of sheets S, but forms a booklet by gluing the plurality of sheets S. Alternatively, a drilling process may be performed.

  The paper discharge mechanism 80 includes a paper discharge roller 80a serving as a discharge unit for discharging the paper S, a liftable paper discharge tray 80b on which the discharged paper S is stacked, and an abutting portion 80c that abuts the rear end of the paper S. , Etc. are provided.

The paper discharge roller 80a is connected to a variable speed paper discharge drive motor M1 and discharges the paper S.
A paper position detection sensor PS is disposed upstream of the paper discharge roller 80a in the paper discharge direction. Then, after the arrival of the paper S is detected by the paper position detection sensor PS, the rotational speed of the paper discharge roller 80a is decelerated in time.
By reducing the rotational speed of the paper discharge roller 80a, the paper discharge operation of the paper discharge unit 90 can be made more reliable.

  A stacking surface SS as a paper stacking unit on which the paper S is stacked is formed on the liftable paper discharge tray 80b, and the paper S discharged by the paper discharge roller 80a is stacked thereon.

As shown in FIG. 3, the abutting portion 80c includes two plate-like members arranged with a predetermined gap on the upstream side with respect to the paper discharge direction of the paper S discharged by the paper discharge roller 80a. It is.
The abutting portion 80c serves as a reference for aligning the rear ends of the sheets S when the sheets S are stacked on the elevating type discharge tray 80b.

  The paper discharge unit 90 is disposed at a position close to the paper discharge mechanism unit 80, and is a mechanism for aligning and stacking the paper S discharged by the paper discharge roller 80a on the liftable paper discharge tray 80b.

The paper discharge unit 90 holds the paper S in a state of being stacked one by one or two at a paper nipping position and moves the paper S to a paper stacking position in the paper stacking unit as a pair of paper nipping members 91. And a support member 93.
Here, the “paper nipping position” refers to the position of the paper S and the pressing member 91 and the supporting member 93 at the moment when the paper S is nipped by the pressing member 91 and the supporting member 93.
The “paper stacking position” is the time when the lower surface of the paper S comes into contact with the stacking surface SS formed on the elevating sheet discharge tray 80b and the rear end of the paper S comes into contact with the butting portion 80c. The positions of the paper S, the pressing member 91, and the supporting member 93 in FIG.

  In the present embodiment, as shown in FIG. 3, a pair of sheet nipping members (pressing member 91 and supporting member 93) is provided in the gap between two abutting portions 80 c. .

As shown in FIG. 5A and the like, the pressing member 91 is swingably held around a rotation shaft 91a parallel to the width direction of the paper S on the upper side of the paper S discharged by the paper discharge roller 80a. Yes.
Specifically, the pressing member 91 is formed in an arm shape, and a rotating shaft 91a that holds the pressing member 91 in a swingable manner is fixed to one end thereof, and the supporting member 93 is pressed to the other end via a sheet. It has a pressing portion 91b.
Further, the pressing member 91 is engaged with a spring member SP that applies a pressing force for pressing the supporting member 93 to the pressing portion 91b, and the spring member SP is rotated in a direction in which the pressing member 91 is rotated counterclockwise. Energized.
The pressing member 91 is separated from the support member 93 and waits at the upper retracted position until the sheet S approaches the sheet nipping position.

In addition, a pressure regulating member 92 that regulates the position of the pressing member 91 is provided at a position adjacent to the pressing member 91, and the pressure regulating member 92 has a forward / reverse rotatable press that drives the pressing regulating member 92. A regulating member drive motor M2 is connected.
The pressing restricting member 92 includes a shaft portion 92a that is connected to the pressing restricting member driving motor M2 and holds the pressing restricting member 92 so as to be rotatable in both forward and reverse directions, and an engaging portion 92b that engages with the pressing member 91. The pressing member 91 swings while being engaged with the engaging portion 92b of the pressing restricting member 92 that rotates in both forward and reverse directions.
Specifically, the pressing member 91 is restricted from rotating counterclockwise by the engagement of an engaging portion 92b attached to one end of a rotating pressing restricting member 92.
Then, when the pressing restricting member drive motor M2 rotates the pressing restricting member 92 counterclockwise according to the control of the control unit 100, the restriction of the counterclockwise rotation of the pressing member 91 is released.
Further, when the pressing restriction member driving motor M2 rotates the pressing restriction member 92 clockwise according to the control of the control unit 100, the counterclockwise rotation of the pressing member 91 is restricted.
Note that the control unit 100 operates the pressing restricting member driving motor M2 in accordance with the conveyance timing of the paper S detected by the paper position detection sensor PS.
Specifically, when the paper S is conveyed by the paper discharge roller 80a and reaches the paper nipping position, the pressure regulating member 92 rotates counterclockwise in response to detection by the paper position detection sensor PS, and Regulations are lifted.

  In the present embodiment, the pressing member 91 is configured to swing while being engaged with the engaging portion 92b of the pressing regulating member 92 that rotates in both forward and reverse directions. However, the pressing member 91 is moved in both forward and reverse directions at a predetermined timing. Any configuration other than the pressure regulating member 92 may be used as long as it can rotate to the right.

  On the other hand, the support member 93 is held on the lower side of the paper S discharged by the paper discharge roller 80a so as to be rotatable around a rotation shaft 94a parallel to the width direction of the paper S.

Specifically, the support member 93 is fixed to one end of a pair of rotating plates 94 having the same size and shape through a pair of shafts 94b.
A pair of rotating shafts 94 a are fixed to the other end of the pair of rotating plates 94, and the pair of rotating shafts 94 a are rotatably held by a holding plate 95.
The pair of rotating shafts 94a is connected to a supporting member driving motor M3 as a supporting member driving means for rotating each of the rotating shafts 94a in the counterclockwise direction. The supporting member driving motor M3 is controlled by the control unit 100. The rotating operation is performed at the same speed and in the same direction at the same time.
The pair of rotating plates 94 are out of phase in the direction of the rotation axis and are arranged so as not to interfere with each other during rotation.

The support member 93 is rotatable by such a pair of rotating plates 94, a pair of rotating shafts 94a, a holding plate 95, a supporting member drive motor M3, and the like. That is, the pair of rotating plates 94 rotate simultaneously in the same direction at the same speed to rotate the support member 93.
Under the control of the control unit 100, the support member drive motor M3 causes the pair of rotating plates 94 to rotate once for the single holding operation of the pressing member 91 and the support member 93 on the paper S.
Note that a sheet nipping surface 93a (described later) of the support member 93 is configured to be always horizontal regardless of the rotation angle of the pair of rotating plates 94, or to be a surface that maintains a constant angle with respect to the horizontal. It is preferable.
As described above, the sheet nipping surface 93a is always a horizontal surface or a surface that maintains a certain angle with respect to the horizontal, so that the nipping operation of the sheet S by the pressing member 91 and the support member 93 is stable and smooth. Done.

In addition, the support member 93 is formed with a paper nipping surface 93a with which the pressing portion 91b of the pressing member 91 contacts via the paper S.
The paper nipping surface 93a is roughened so as to increase the friction coefficient. The friction coefficient of the surface of the sheet holding surface 93 a is set to be larger than the friction coefficient of the pressing portion 91 b of the pressing member 91 and larger than the friction coefficient between the sheets S.
In this way, by setting the friction coefficient of the sheet holding surface 93a of the support member 93 to be larger than the friction coefficient of the pressing portion 91b of the pressing member 91 and larger than the friction coefficient between the sheets S, the ascending and descending Even when the paper S stacked on the uppermost surface of the paper discharge tray 80b is shifted to the downstream side in the paper transport direction, the position can be easily corrected.
The configuration for increasing the coefficient of friction is not limited to the roughing process, and the support member 93 may be formed of a resin molded part, and a large number of minute protrusions may be formed on the paper holding surface 93a. Another member made of rubber, foamed soft resin, or the like may be attached.

Further, a friction member 96 is provided on the lower surface of the support member 93 (the surface opposite to the sheet nipping surface 93a) via a spring member 96a.
The friction member 96 is a friction plate formed of a material made of rubber or foamed resin. The friction coefficient at the sheet contact surface (lower surface) of the friction member 96 is set to a value larger than the friction coefficient between the sheets of the plurality of sheets S stacked on the elevating sheet discharge tray 80b.
The paper contact surface of the friction member 96 can be displaced by a spring member 96a. Since the contact surface of the friction member 96 with the sheet S is displaceable, the frictional resistance to the sheet S can be kept substantially constant even when the thickness of the sheet bundle loaded on the elevating type discharge tray 80b changes. it can.

In the present embodiment, the pressing member 91 and the support member 93 described above can drive both or only one of them according to a user's setting operation.
Specifically, when the paper S is discharged in a state where two sheets are stacked by the paper discharge roller 80a, both the pressing member 91 and the support member 93 are driven.
When the paper is discharged one by one by the paper discharge roller 80a, both the pressing member 91 and the support member 93 may be driven, or only one of them may be driven.
When both the pressing member 91 and the support member 93 are set to be driven, it is possible to further improve the paper alignment state when the paper S is placed on the liftable paper discharge tray 80b. On the other hand, when only one of the pressing member 91 and the support member 93 is set to be driven, there is only one drive location, so that power saving and noise reduction can be achieved.

Further, the paper discharge unit 90 is a pair of alignment members as paper alignment means for aligning the end position of the paper S in a direction perpendicular to the paper discharge direction of the paper S discharged to the liftable paper discharge tray 80b. 97, 98.
As shown in FIG. 3, the pair of alignment members 97 and 98 are disposed on the downstream side in the sheet discharge direction and above the elevating sheet discharge tray 80b.
The pair of alignment members 97 and 98 are installed so as to face each other with a predetermined gap in the paper width direction, and can be rotated in a direction in which they are in contact with and away from the elevating type discharge tray 80b around the rotation axis AX. It has become.

(Control unit 100)
As shown in FIG. 4, the control unit 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, and the like.
The ROM 102 of the control unit 100 stores a control program and various processing programs for controlling the above-described units, and the RAM 103 includes a work area for the CPU 101.
The CPU 101 comprehensively controls the operation of each part of the image forming system 1000 in cooperation with this control program and various processing programs.

  For example, when the paper S is discharged in a state where two sheets are overlapped by the paper discharge roller 80a, the control unit 100 drives both the pressing member 91 and the support member 93, and the paper discharge roller 80a drives each sheet. When the sheet is discharged, control is performed so that at least one of the pressing member 91 and the supporting member 93 is driven.

Specifically, when the paper S is discharged in a state in which two sheets are overlapped by the paper discharge roller 80a, the control unit 100 determines this by the paper interval (paper interval), and determines the pressing restriction member drive motor M2 and The support member drive motor M3 is driven to drive both the pressing member 91 and the support member 93.
On the other hand, when the paper is discharged one by one by the paper discharge roller 80a, the control unit 100 determines that the pressing restricting member driving motor M2 and the support are in accordance with the user setting operation by the operation display unit B2 as setting means. Both or any one of the member drive motors M3 is driven, and both or any one of the pressing member 91 and the support member 93 is driven.

In addition, when the paper is discharged one by one by the paper discharge roller 80a and the setting operation of the user is not performed, the control unit 100 presses the pressing member according to the type of the paper to be discharged. 91 and driving of the support member 93 are determined.
Specifically, for example, the control unit 100, when the basis weight of paper ejected is ^{40g / m 2 ~80g / m 2} ( irrespective the type of paper), the pressing member 91 and the support member 93 Drive both. This is because the paper with the basis weight has no paper strain or the posture of the paper is not stable.
In addition, when the discharged paper is coated paper (paper coated on the surface), the control unit 100 drives both the pressing member 91 and the support member 93 regardless of the basis weight of the paper. . This is because the coated paper has high adhesion between the sheets, and the return on the elevating sheet discharge tray 80b is not stable.
Then, the control unit 100 drives only the support member 93 for sheets other than the above conditions.

Further, the control unit 100 drives at least one of the pressing member 91 and the support member 93 in accordance with the interval between sheets discharged by the paper discharge roller 80a.
Specifically, for example, when the normal printing speed is 100 sheets per minute, only the support member 93 is driven because the interval between the conveyed sheets is short.
Further, when two sheets are stacked, the sheet is conveyed at a double sheet interval, and therefore, in the case of this sheet interval, the pressing member 91 and the support member 93 are driven.

  In the present embodiment, the paper discharge device is configured by the paper discharge unit 90 and the control unit 100 described above.

  Next, the operation of the paper discharge unit 90 in the present embodiment will be described with reference to FIGS.

First, a case where the two sheets S1 and S2 in a state of being stacked by the paper discharge roller 80a are discharged and the pressing member 91 and the support member 93 are driven will be described.
5 to 7 show a state in which a plurality of sheets are already stacked on the liftable sheet discharge tray 80b before the sheets S1 and S2.

  Before the discharged sheets S1 and S2 reach the sheet nipping position, when the leading ends of the sheets S1 and S2 are sandwiched between the discharge rollers 80a, the pressing member 91 waits at a retracted position separated from the support member 93. ing. Further, the support member 93 stands by at a sheet nipping position where the sheets S1 and S2 are nipped (see FIG. 5A).

  Next, when the papers S1 and S2 are conveyed by the paper discharge roller 80a and reach the paper nipping position, the pressure regulating member 92 rotates counterclockwise according to the detection by the paper position detection sensor PS, and the pressure is pressed accordingly. The restriction of the member 91 is released, and the pressing member 91 abuts on and presses the support member 93 so as to rotate counterclockwise by the urging force of the spring member SP and pinch the rear ends of the sheets S1 and S2. (See FIG. 5 (b)).

When the support member drive motor M3 is rotated after a lapse of a predetermined time from the detection of the sheets S1 and S2 by the sheet position detection sensor PS, the support member 93 starts to move due to the rotation of the pair of rotation plates 94 associated therewith. . The support member 93 is rotated counterclockwise as the pair of rotation plates 94 are rotated.
When the support member 93 rotates, the pressing member 91 moves following the moving support member 93 while pressing the support member 93 while holding the sheets S1 and S2 therebetween (FIG. 6A). reference).

In addition, after the sheets S1 and S2 are nipped between the pressing member 91 and the support member 93 at the sheet nipping position, the rear ends of the sheets S1 and S2 are discharged from the sheet discharge roller 80a (sheets). The paper S1 and S2 are conveyed by the conveying force of the paper discharge roller 80a (until the rear ends of S1 and S2 are separated from the nip portion of the paper discharge roller 80a).
When the trailing ends of the sheets S1 and S2 move away from the nip portion of the sheet discharge roller 80a, the conveying force by the sheet discharge roller 80a disappears, and the sheets S1 and S2 are held between the pressing member 91 and the support member 93. In this state, it moves according to the movement of the support member 93.

When the sheets S1 and S2 reach the sheet stacking position, the sheet nipping surface 93a of the support member 93 is separated from the sheet S, and the support member 93 is separated from the pressing member 91 and is upstream in the direction opposite to the sheet discharge direction. (See FIG. 6B).
Then, the pressing member 91 is urged by the spring member SP, and presses the sheets S1 and S2 against the liftable sheet discharge tray 80b (see FIG. 7A). In this state, the loading of the sheets S1 and S2 onto the liftable sheet discharge tray 80b is completed.
Thereafter, the pressing member 91 rotates clockwise in accordance with the clockwise rotation of the pressing restricting member 92, returns to the original retracted position locked to the pressing restricting member 92, and the support member 93 rotates counterclockwise. It rotates to return to the paper nipping position (see FIG. 7B).

  At this time, since the friction coefficient of the sheet holding surface 93a of the support member 93 is larger than the friction coefficient between the pressing portion 91b of the pressing member 91 and the sheet, the rear end of the lower sheet S1 is pressed against the butting portion 80c. You can guess.

In addition, when the rear end of the uppermost sheet S stacked on the elevating sheet discharge tray 80b is shifted to the downstream side in the discharge direction from the rear end of the sheet S1, the friction member 96 contacts the uppermost sheet S. The shift can be corrected by the action when contacting.
That is, as shown in FIG. 6B, the friction member 96 provided on the support member 93 comes into contact with the upper surface of the uppermost sheet S, and the sheet S is urged toward the upstream side in the sheet discharge direction. The rear end of the paper S is abutted against the abutting portion 80c.

At this time, since the spring member 96a expands and contracts in accordance with the thickness of the bundle of sheets stacked on the elevating type discharge tray 80b, the friction member 96 always has a suitable height of the elevating type discharge tray 80b. It comes into contact with the uppermost sheet.
Thereafter, in the same manner, the paper S is discharged from the paper discharge roller 80a, and the paper bundle with the rear end aligned is stacked on the liftable paper discharge tray 80b.

  In addition, when the paper S is discharged one by one by the paper discharge roller 80a and the pressing member 91 and the support member 93 are driven, the same as the case where the two stacked sheets S1 and S2 are discharged. In this way, the bundle of sheets with the aligned end portions is stacked on the elevating sheet discharge tray 80b.

Next, a case where the paper S is discharged one by one by the paper discharge roller 80a and only the pressing member 91 is driven will be described.
When only the pressing member 91 is driven, the support member 93 has moved to a retracted position (see FIG. 7A) that does not hinder the swinging of the support member 93.
Then, at the timing when the rear ends of the sheets S1 and S2 move away from the nip portion of the paper discharge roller 80a, the pressing restricting member 92 rotates counterclockwise, and the pressing member 91 is energized by the spring member SP. It rotates counterclockwise and presses the trailing edge of the paper S.
As a result, the sheet S does not have its own weight but falls by the pressing force of the pressing member 91 and is stacked on the liftable sheet discharge tray 80b.

Next, a case where the paper S is discharged one by one by the paper discharge roller 80a and only the support member 93 is driven will be described.
When only the support member 93 is driven, the pressing member 91 stands by at a retracted position (see FIG. 5A) separated from the support member 93.
The support member 93 stands by at a paper nipping position where the paper S is nipped. Note that the sheet S is not nipped because the pressing member 91 is not driven, but the expression “sheet nipping position” is used for convenience.

Next, when the paper S is conveyed by the paper discharge roller 80a and reaches the paper nipping position, and the paper position detection sensor PS detects this, the support member 93 has passed a predetermined time from the detection of the paper S by the paper position detection sensor PS. Later, the movement is started by the rotation of the pair of rotation plates 94. The support member 93 is rotated counterclockwise as the pair of rotation plates 94 are rotated.
When the trailing edge of the paper S moves away from the nip portion of the paper discharge roller 80 a, the conveyance force by the paper discharge roller 80 a disappears, and the paper S moves according to the movement of the support member 93.
Thereafter, when the sheet S reaches the sheet stacking position, the sheet nipping surface 93a of the support member 93 moves away from the sheet S and moves upstream in the direction opposite to the sheet discharge direction. Loading on the paper plate 80b is completed.
The sheet S stacked on the elevating sheet discharge tray 80b has a trailing edge at the abutting portion 80c due to the action when the friction member 96 is brought into contact with the sheet S2 in the next cycle of the rotation of the support member 93. It is hit.
As a result, the sheet bundle with the rear end aligned is stacked on the liftable sheet discharge tray 80b.

As described above, according to the present embodiment, since the paper S is placed on the elevating type discharge tray 80b using at least one of the pressing member 91 and the support member 93, the paper is placed on the paper placement table. The paper alignment state at the time can be improved and the time until the paper is placed can be shortened.
Further, when the paper is discharged in a state where two sheets are stacked by the paper discharge roller 80a, both the pressing member 91 and the support member 93 are driven, and the paper is discharged one by one by the paper discharge roller 80a. It is possible to control to drive at least one of the pressing member 91 and the supporting member 93.
For this reason, when both the pressing member 91 and the support member 93 are set to be driven, the paper alignment state when the paper S is placed on the liftable discharge tray 80b can be further improved. When only one of the member 91 and the support member 93 is set to be driven, there is only one drive location, so that power saving and noise reduction can be achieved.

Further, according to the present embodiment, when a sheet is discharged one by one by the sheet discharge roller 80a, the user performs a setting operation for driving both or one of the pressing member 91 and the support member 93. An operation display unit B2 is provided, and at least one of the pressing member 91 and the support member 93 is driven according to a setting operation by the operation display unit B2.
For this reason, it becomes possible for a user to set operation | movement of the press member 91 and the supporting member 93 according to the installation environment of an apparatus, etc., and the convenience improves.

Further, according to the present embodiment, the support member 93 abuts on the uppermost sheet S stacked on the stacking surface SS, and the uppermost sheet S is an upstream abutment portion with respect to the sheet discharge direction. A friction member 96 is provided to bias toward 80c.
For this reason, when the trailing edge of the uppermost sheet stacked on the stacking surface SS is displaced, the displacement can be corrected.

Further, according to the present embodiment, when the paper is discharged one by one by the paper discharge roller 80a, it is determined which of the pressing member 91 and the support member 93 is driven according to the type of the paper to be discharged. The
For this reason, the pressing member 91 and the supporting member 93 can be driven appropriately according to the type of paper.

In addition, according to the present embodiment, at least one of the pressing member 91 and the support member 93 is driven according to the interval between the sheets discharged by the paper discharge roller 80a.
For this reason, the suitable position of the conveyed paper can be held between the pressing member 91 and the supporting member 93.

In the above-described embodiment, the control unit 100 has been described as controlling the overall operation of the image forming system 1000. However, the control unit that controls each of the image forming apparatus B and the post-processing apparatus C is separately provided. It is good also as providing in.
In this case, drive control of the pressing member 91 and the support member 93 may be performed by the control unit of the post-processing apparatus C.

  Further, the image forming apparatus B and the intermediate transport unit C1 may be formed integrally and the paper discharge unit 90 may be provided in the intermediate transport unit C1.

1000 Image forming system A Large-capacity paper feeder B Image forming apparatus B2 Operation display section (setting means)
C Post-processing device C1 Intermediate transport unit C2 Post-processing unit 80 Paper discharge mechanism 80a Paper discharge roller (discharge means)
80b Elevating type paper discharge tray SS Stacking surface (paper stacking section)
80c Abutting part 90 Paper discharge part (paper discharge device)
91 Press member (paper pinching member)
91a Rotating shaft 91b Pressing portion 92 Pressing restricting member 93 Support member (paper nipping member)
93a Paper holding surface 94 Rotating plate 95 Holding plate 96 Friction member 96a Spring members 97, 98 Alignment member 100 Control unit (paper discharge device)

Claims (6)

A paper stacking unit for stacking sheets discharged one by one or two by the discharge means;
An abutting portion that abuts the rear end of the paper stacking direction of the paper loaded on the paper stacking portion;
A sheet discharge unit having a pair of sheet nipping members that nipping the sheet in a state where each sheet or two sheets are stacked at a sheet nipping position and moving the sheet to a sheet stacking position in the sheet stacking unit;
The pair of paper nipping members is
A support member held on the lower side of the paper discharged by the discharge means so as to be rotatable around a rotation axis parallel to the width direction of the paper;
A pressing member held swingably about a rotation axis parallel to the width direction of the paper on the upper side of the paper discharged by the discharging means;
With
When the paper is discharged in a state where two sheets are stacked by the discharge means, both the pressing member and the support member are driven,
A paper discharge apparatus comprising: a control unit that controls to drive at least one of the pressing member and the support member when the discharge means discharges the sheet one by one. A setting unit for performing a setting operation for the user to drive both or one of the pressing member and the support member when the discharge unit discharges the paper one by one;
The sheet discharging apparatus according to claim 1, wherein the control unit drives at least one of the pressing member and the support member in accordance with a setting operation by the setting unit. The support member is
When rotating and moving upstream with respect to the paper discharge direction, the uppermost paper loaded on the paper stacking unit abuts on the uppermost paper and the uppermost paper is placed upstream of the paper discharge direction. The paper discharge device according to claim 1, further comprising a friction member that urges toward the abutting portion. The controller is
3. The apparatus according to claim 1, wherein when the sheet is discharged one by one by the discharge unit, at least one of the pressing member and the support member is driven according to a type of the discharged sheet. Paper ejector. The controller is
5. The paper discharge device according to claim 1, wherein at least one of the pressing member and the support member is driven in accordance with an interval of the paper discharged by the discharge unit. In an image forming system comprising: an image forming apparatus that forms an image on a sheet; and a post-processing apparatus that performs post-processing on a sheet on which an image is formed by the image forming apparatus.
Comprising the paper discharge device according to any one of claims 1 to 5,
The post-processing apparatus includes the paper discharge unit.

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