JP2002226128A - Sheet processing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in a device that the discharging of next bundle of sheets should be started after the bundle of sheets after stapling has been discharged onto a stack tray, which decreases processing speed. SOLUTION: This sheet processing device comprises a stapling means 419 for binding the bundle of sheets bundled by a bundling means 417, a bundle conveying means 421 for conveying the bundle of sheets bundled by the bundling means to a stack tray 411, and a bundle pressing means 420 capable of executing the bundle pressing motion for pressing the bundle of sheets stacked on the stack tray, a binding discharging mode for binding the bundle of sheets by the stapling means and conveying the same to the stack tray, and a non- binding discharging mode for conveying of the bundle of sheets onto the stack tray without binding the same, can be selectively determined, the bundle pressing motion of the bundle pressing means is permitted when the non-binding discharging mode is determined, and the bundle pressing motion of the bundle pressing means is not permitted when the binding discharging mode is determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a sheet processing apparatus for bundling sheets or the like on which images are formed.

[0002]

2. Description of the Related Art The above-described sheet processing apparatus is provided in an image forming apparatus such as a copying machine and the like, and a plurality of sheets on which images have been formed are bundled and discharged, or further discharged in a state of being stapled and stapled. Or

FIG. 1 shows a basic configuration of a copying machine provided with the above-mentioned sheet processing apparatus. Printer unit 30
The sheet on which the image has been formed at 0 is carried into the finisher (sheet processing apparatus) 400 by the discharge roller 118. The carried-in sheet is ejected by the ejection roller 415.
It is transported onto the intermediate processing tray 430 (see FIG. 25).

[0004] The sheets stacked on the intermediate processing tray 430 are aligned and bound by an alignment plate 412, and are further stapled by a staple unit 419 in a staple mode (binding discharge mode).
The sheet is discharged onto the stack tray 411.

[0005] When the sheet bundle is discharged onto the stack tray 411, the bundle pressing member 42 rotatably mounted.
0 makes one rotation and presses the upper surface of the already stacked sheet bundle. By this bundle holding operation, the stack tray 41
By pressing the uppermost surface of the sheet bundle stacked on 1,
The top sheet of the stacked sheet bundle is prevented from being displaced by the next discharged sheet bundle.

[0006]

By the way, such a sheet processing apparatus is required to have a processing capability equivalent to the productivity of the image forming apparatus as much as possible.

However, in the above-described sheet processing apparatus, after the stapling process, it is necessary to wait for the next sheet bundle to be discharged onto the stack tray until the discharge process of the sheet bundle onto the stack tray is completed. For this reason, there is a possibility that an increase in the copying speed on the image forming apparatus side may be hindered.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet processing apparatus which simplifies a sheet bundle discharge process in a binding discharge mode and enables a high-speed processing.

[0009]

In order to achieve the above object, according to the present invention, a bundle processing means for bundling a plurality of sheets sequentially supplied, and a staple means for binding a sheet bundle bound by the bundling means are provided. A bundle transporting unit that transports a sheet bundle bundled by the bundle processing unit to a stacking tray;
A bundle holding unit capable of holding a bundle of sheets stacked on the stacking tray; a binding discharge mode in which the sheet bundle is bound by the staple unit and transported to the stacking tray by the bundle transport unit; and a binding unit is bound by the staple unit. In a sheet processing apparatus capable of selectively setting a non-binding discharge mode in which a bundle is conveyed to a stack tray by a bundle conveyance unit, when the non-binding discharge mode is set, the bundle holding unit performs a bundle pressing operation, When the binding discharge mode is set, control means is provided for preventing the bundle pressing means from performing the bundle pressing operation.

Here, when the next sheet bundle is discharged onto the sheet bundle stacked on the stacking tray, if the already stacked sheet bundle has been bound by the stapling means, this sheet bundle is discharged. The uppermost sheet is hardly displaced.

For this reason, according to the present invention, when the sheet bundle already stacked on the stacking tray has not been subjected to the binding processing and the non-binding discharge mode in which the uppermost sheet of the sheet bundle is easily shifted is set. Is to prevent the above-mentioned misalignment by making the bunch-pressing means perform the bunch-pressing operation, while binding the sheet bundle already stacked on the stacking tray so that the topmost sheet is less likely to be misaligned. When the mode is set, the bundle holding operation by the bundle holding means is omitted, and the next sheet bundle can be discharged to the stacking tray in a short time.

When the bundle conveying means and the bundle pressing means are configured to be selectively driven by the same drive source in forward and reverse rotations, the bound sheet bundle is transferred to the stacking tray by the bundle conveying means. Since the bundle pressing means is not driven after being conveyed, preparation for conveying the next sheet bundle in a short time, such as returning the bundle conveying means to the position for conveying the next sheet bundle by the driving source, is performed. It can be completed.

By providing such a sheet processing apparatus in the image forming apparatus, it is possible to increase the processing speed of the entire image forming apparatus.

Further, in the sheet processing means of the present invention,
Each time the sheet bundle is conveyed to the stacking tray by the bundle conveying means, when performing the lifting operation of the stacking tray for detecting the stacking amount of the sheet bundle on the stacking tray and setting the elevating position of the stacking tray, After the bound sheet bundle is discharged and stacked on the stacking tray, the stacking tray can be moved up and down without waiting for the bundle pressing operation of the bundle pressing member, so that the next sheet bundle can be discharged in a short time. It is possible to start with.

[0015]

FIG. 1 shows a basic configuration of an entire image forming apparatus provided with a sheet processing apparatus according to an embodiment of the present invention.

First, the image forming apparatus main body will be described. The image forming apparatus main body includes an image reader unit 200,
And a printer unit 300. The document feeder 100 is mounted on the image reader unit 200. The original feeding device 100 separates an original set upward, feeds the original one by one sequentially from the top page to the left, conveys the original onto a platen glass 102 via a curved path, and reads the original. Then, the sheet is discharged to the sheet discharge tray 112.

The original is read by the scanner unit 104.
The light of the lamp 103 is irradiated on the original, and the reflected light from the original is reflected by the mirrors 105, 106, 107 and the lens 10
8 to the image sensor 109.

The image of the document read by the image sensor 109 is subjected to image processing and sent to the exposure control unit 110. Exposure control section 110 outputs a laser beam according to the image signal. This laser beam is applied to the photosensitive drum 111, and an electrostatic latent image is formed on the photosensitive drum 111. The electrostatic latent image on the photosensitive drum 111 is developed with a developer (toner) supplied from a developing device 113, and the photosensitive drum 11
The toner image on 1 is transferred by the transfer unit 116 to a sheet fed from any of the cassettes 114 and 115, the manual paper feed unit 125, and the double-sided conveyance path 124.

The sheet on which the toner image has been transferred is subjected to toner fixing processing in a fixing unit 117. The sheet that has passed through the fixing unit 117 is guided to a discharge roller 118, and is discharged from the printer unit 300 by the discharge roller 118 with the surface on which the toner image has been transferred facing downward (face down).

When the document is fed face down, the document is discharged in the correct page order when forming images sequentially from the first page, such as when using the document feeder 100 or printing an image output from a computer. You.

The sheet discharged from the discharge roller 118 is sent to a finisher 400 which is the above-described sheet processing apparatus. The finisher 400 performs a binding process of the sheet bundle and the like.

When an image is formed on both sides of the sheet, the sheet that has passed through the fixing unit 117 is
To the path 122, switch back to the double-sided conveyance path 124, and again pass through the transfer unit 116 and the fixing unit 117 to be discharged from the printer unit 300.

FIG. 2 shows a configuration of an electric circuit for controlling the image forming apparatus of the present embodiment. CPU circuit unit 15
Reference numeral 0 denotes a CPU, and a document feeder control unit 101, an image reader control unit 201, an image signal control unit 202, a printer control unit 301, a finisher control unit in accordance with a program stored in the ROM 151 and settings of the operation unit 1. (Control means) The operation of the 401 and the external I / F 203 is controlled.

The document feeder control unit 101 controls the document feeder 100, the image reader control unit 201 controls the image reader 200, and the printer control unit 301 controls the printer unit 300.
And the finisher control unit 401 controls the finisher 400.

The RAM 152 is used as an area for temporarily storing control data and as a work area for operations involved in control.

An external I / F 203 is an interface from the computer 204, develops print data into an image, and outputs the image to the image signal control unit 202.

An image read by the image sensor 109 is output from the image reader control unit 201 to the image signal control unit 202, and the image output from the image signal control unit 202 to the printer control unit 301 is input to the exposure control unit 110. Is done.

FIG. 3 shows the configuration of the image signal control unit 202. The image processing unit 205 performs an image correction process and an editing process according to the settings in the operation unit 1. The image is output to the printer control unit 301 via the line memory 206 and the page memory 207.

The hard disk 208 is used as necessary, for example, when changing the page order.

FIG. 4 shows the configuration of the finisher 400. The sheet discharged from the printer unit 300 is
The sheet is sent to a sheet discharge roller 415 via a path 416.
A paper discharge roller 415 is a bundle discharge belt (bundle conveying means) 421.
Discharged up. Here, a low-friction intermediate processing tray 430 shown in FIG. 25 is provided at a position several millimeters higher in parallel with the bundle discharge belt 421, and is discharged onto the bundle discharge belt 421 by the discharge rollers 415. The sheet is also placed on the intermediate processing tray 430.

As shown in FIG. 16, the discharged sheet falls to the lower left along the obliquely provided intermediate processing tray 430 (or bundle discharge belt 421).

At this time, as shown in FIG. 17, when the fan-shaped return roller 417 rotates clockwise,
A friction member provided in the arc of the return roller 417 abuts on the sheet discharged onto the intermediate processing tray 430 and drives the sheet in the lower left direction.
18 The return roller 417 and the stopper plate 418 constitute a bundle processing unit described in the claims.

Thus, a plurality of sheets are stored in the intermediate processing tray 4.
Each time the sheets are sequentially ejected onto the sheet 30, the ends of the sheets are brought into contact with the stopper plate 418, and the sheets are bundled in a state where the ends are aligned.

The stapling unit 419 is provided on the front side on the side of the stopper plate 418, and performs a stapling process on a sheet bundle on the intermediate processing tray 430.

Since the length of the intermediate processing tray 430 may not be sufficient for stacking sheets, the intermediate processing tray stacking auxiliary plate 421B is provided on the bundle discharge belt 421 to increase the length of the sheet stacking surface. In.

As shown in detail in FIG. 7, the alignment plates 412 shown in FIG. 4 are provided on the near side and the back side, and align the sheets on the intermediate processing tray 430. In addition, by the operation of the alignment plate 412, as shown in FIG. 18, offset stacking in which a sheet bundle stacked on the stack tray 411 is sorted between the near side and the far side can be performed.

As shown in FIG. 19, the intermediate processing tray 43
The sheet on 0 is discharged onto the stack tray 411 by a bundle discharge lever 421A provided on the bundle discharge belt 421. The bundle discharge lever 421A is connected to the bundle discharge belt 421.
Is rotated clockwise to push up the sheet bundle in the upper right direction, and the stack tray (stacking tray) 41
Discharge on top.

The bundle discharge lever 421A moves within a notch provided in the intermediate processing tray 430.

The stack tray 411 moves up and down in accordance with the stacking amount of the sheet bundle. Further, the stack tray 41
When the sheet bundle is discharged onto the stack tray 1, the stack holding member 420 makes one rotation in the clockwise direction, during which the stack tray 41 is rotated.
After the sheet 1 is lowered by a predetermined amount and then raised, the upper surface of the sheet bundle is pressed by the bundle pressing member 420.

Thus, it is possible to prevent the uppermost sheet of the already stacked sheet bundle from being pushed rightward by the sheet bundle to be discharged onto the stack tray 411 next.

FIG. 5 shows a sensor and a motor in the finisher 400. The motor M1 drives the discharge roller 415 and the return roller 417, and the motor M2 drives the bundle pressing member 420 and the bundle discharge belt 421.

The discharge roller 415 is a one-way clutch 4
25, the return roller 417 is driven by the motor M1 via the one-way clutch 426.
When the motor M1 rotates forward, only the discharge rollers 415 rotate in the direction of transporting the sheet onto the intermediate processing tray 430, and when the motor M1 rotates reversely, only the return roller 417 rotates only the intermediate processing tray 430.
The sheet rotates in a direction (clockwise direction) in which the upper sheet abuts against the stopper plate 418.

The bundle discharge belt 421 is driven by a one-way clutch 422, and the bundle pressing member 420 is driven by a motor M2 via a one-way clutch 424. When the motor M2 rotates forward, the bundle discharge belt 421
Only the bundle rotates in the direction of discharging the sheet bundle on the intermediate processing tray 430 onto the stack tray 411 (clockwise), and when rotated in reverse, only the bundle holding member 420 rotates clockwise.

As described above, the paper discharge roller 415 and the return roller 417, the bundle discharge belt 421 and the bundle pressing member 420
Are configured to be selectively driven by the forward and reverse rotation of one motor, thereby achieving cost reduction.

A flag (not shown) is attached to the rotating shaft of the return roller 417. By detecting this flag with the sensor S3, it can be determined whether the return roller 417 is at the home position. .

Further, the discharge roller 4 is connected to the image forming apparatus main body.
Sensor S2 provided in the middle of the path 416 toward
In response to the detection of the leading edge of the sheet, the paper discharge roller 415 starts, stops at a later-described timing after decelerating the paper discharge roller 415.

The sensor S5 detects a sheet on the bundle discharge belt 421, and the sensor S11 detects a sheet on the stack tray 411.

The sensor S8 has a bundle discharge lever 421A.
Detects whether or not is located at the home position. Return roller 417 and bundle discharge lever 421 in FIG.
The position of A is each home position. Also,
The home position of the bundle discharge lever 421A is set slightly to the left of the stopper plate 418.

The return roller 417 makes one rotation in the clockwise direction from the home position each time one sheet is discharged onto the intermediate processing tray 430. Return roller 4
When the roller 17 rotates clockwise, the paper discharge roller 415 does not rotate as described above.

Further, the bundle discharge belt 421 rotates by と き に when discharging the sheet bundle. However, if the bundle discharge belt 421 is rotated by そ の ま ま, the bundle discharge lever 421A interferes with the sheet bundle stacked on the stack tray 411. Would. This position is controlled so that the stack tray 411 is at a distance suitable for dropping the sheet bundle when discharging the sheet bundle. In this state, the upper surface of the sheet bundle stacked on the stack tray 411 is set to the bundle discharge lever. This is because it is on the orbit of 421A.

Therefore, in the present embodiment, the bundle discharge lever 4
When 21A is substantially parallel (substantially parallel to the intermediate processing tray 430) with the linear portion of the bundle discharge belt 421 shown in FIG. 6, the bundle discharge belt 421 (that is, the motor M2) is temporarily stopped, and the stack tray 411 is stopped. When is lowered, it is rotated again and stopped at the home position.

This prevents the bundle discharge lever 421A from engulfing the sheets on the stack tray 411,
Further, it is possible to prevent the trailing end of the sheet bundle from remaining on the bundle discharge belt 421.

FIG. 7 shows a driving mechanism of the matching plate 412. The matching plate 412A is provided on the back side, and the matching plate 412B is provided on the near side. Motor M3 is a matching plate 4
12A, and the motor M4 drives the matching plate 412B.

When each motor rotates in the black arrow direction, each rotating member in the figure rotates in the black arrow direction, and when each motor rotates in the white arrow direction, each rotating member rotates in the white arrow direction.

The sensor S6 is provided for detecting the home position of the matching plate 412A, and the sensor S7 is provided for detecting the home position of the matching plate 412B.

When the sheet bundle is stapled by the stapling unit 419, the alignment plate 412B is set to the front side, and every time a sheet is discharged onto the bundle discharge belt 421 so as to abut the sheet against the alignment plate 412B. The sheet is pushed by the matching plate 412A.

When performing the offset discharge without performing the stapling process, when the alignment plates 412A and 412B are set at the distances corresponding to the sheet widths, the sheet is placed on one of the alignment plates 412A and 412B. Is pressed each time the sheet is discharged onto the bundle discharge belt 421 so that the sheet is discharged.

Then, at the time of offset discharge, the position of the alignment plates 412A, 412B is alternately shifted to the near side, the back side, the near side, the back side every time the sheet bundle is discharged. Thus, as shown in FIG. 18, the sheet bundles stacked on the stack tray 411 are stacked in an offset (shifted) state for each sheet bundle.

It is to be noted that whether or not to perform offset sheet ejection can be appropriately set by the user using the operation unit 1 of the image forming apparatus main body, and the setting contents are notified from the image forming apparatus main body to the finisher 400, and The finisher 400 operates accordingly.

Here, the alignment plate 412 and the return roller 417
Will be described. As previously mentioned,
The return roller 417 moves the sheet in the direction of the stopper plate 418, and the alignment plate 412 acts to move the sheet in a direction perpendicular to the sheet discharging direction.

As described above, the return roller 417 and the alignment plate 4
Since 12 acts in different directions, the overlapping of both operations adversely affects the seat. Therefore, the matching plate 412
Is controlled so that it comes into contact with the sheet when the operation of the return roller 417 is completed.

FIG. 8 shows a mechanism for raising and lowering the stack tray 411. The motor M5 drives the stack tray 411 to move up and down. The sensor S13 includes a stack tray 411
Has reached the upper limit position, and the sensor S12 detects that the stack tray 411 has reached the lower limit position.

The flag 423 indicates that the stack tray 41
1 is pushed inward by the contact of the sheets stacked on it, and the pushed flag 423 is set to the sensor S1.
The height of the sheet can be detected by detecting 0.

When the motor M5 rotates in the black arrow direction, each rotating member in the figure rotates in the black arrow direction, and when the motor M5 rotates in the white arrow direction, each rotating member rotates in the white arrow direction.

The reason why the stack tray 411 is lowered when discharging the sheet bundle is to prevent the bundle discharge lever 421A from interfering with the sheets on the stack tray 411, and the sensor S10 of the stack tray 411 is in the non-detection state. Descend to the position. The reason for raising the stack tray 411 after lowering it is to move the upper surface of the newly discharged sheet bundle to a position suitable for discharging the next sheet bundle.

If the sheet bundle to be discharged is not stapled, the bundle pressing member 42 is moved before the stack tray 411 after the discharge of the sheet bundle is moved down.
0 is rotated clockwise so that the sheet bundle on the stack tray 411 is pressed.

FIG. 9 is a flowchart for controlling the driving of the discharge roller 415 in the finisher 400. If the finisher 400 is to be made compact as shown in FIG.
The distance between is shorter. On the other hand, in consideration of the stackability when the discharge roller 415 discharges the sheet onto the bundle discharge belt 421, the sheet is conveyed at a high speed by the discharge roller 415 during the conveyance of the sheet, and the rear end of the sheet is discharged by the discharge roller 415 It is desirable that the paper discharge roller 415 be decelerated at the point when the sheet exits from the position to prevent the sheet from jumping over the bundle discharge belt 421.

Usually, when decelerating based on the trailing edge of the sheet, a method of decelerating according to the detection of the trailing edge of the sheet is employed. If the distance is short, it may not be enough to improve the stackability even if the sheet can be prevented from jumping over the bundle discharge belt 421.

Therefore, the following control is performed in order to obtain a better loadability with a compact finisher.

A finisher control section 401 for controlling the operation of the finisher 400 receives size information of each sheet from the CPU circuit section 150 of the image forming apparatus main body. First, it is determined whether the size of the sheet discharged by the discharge roller 415 is the standard size (S101). When the size is the standard size, in response to the sensor S2 being turned on (the leading edge of the sheet has passed) (S102), the drive of the paper discharge roller 415 (motor M1) is turned on (S103), and then the amount according to the sheet size is set. Then, it is determined whether or not the discharge roller 415 has rotated based on whether or not a time (standby time) corresponding to the sheet size has elapsed (S104).

The motor M1 is a stepping motor, and its rotation amount is constantly managed by the finisher control unit 401.

When the time (standby time) corresponding to the sheet size has elapsed, the discharge roller 415 is decelerated (S105) and stopped (S106). Step S
The standby time at 104 is set in consideration of the sheet size and the deceleration time of the discharge roller 415 so that the trailing edge of the sheet comes out immediately before the discharge roller 415 stops at step S106. Thus, it is possible to prevent the discharged sheet from flying too far on the bundle discharge belt 421.

On the other hand, if it is determined in step S101 that the sheet is not of the standard size, that is, it is a free size sheet, the driving of the sheet discharge roller 415 is performed in response to the sensor S2 being turned on (the leading edge of the sheet has passed) (S107). Is turned on (S108). Then, in response to the sensor S2 being turned off (the rear end of the sheet passes) (S10
9) The paper discharge roller 415 is decelerated (S110) and stopped (S111).

Here, in the case of the position of the sensor S2 shown in FIG. 5, the rear end of the sheet falls out of the paper discharge roller 415 before being sufficiently decelerated in step S110. However, although this timing is not enough to secure the stackability, the sheet does not jump over the bundle discharge belt 421. If the sensor S2 is arranged more upstream, the stackability is improved, but since the sensor S2 is also used for detecting a sheet jam, the sensor S2 cannot be moved much upstream.

Also, the position of the sensor S2 is left as it is,
Although another sensor may be added, it is not preferable because the cost increases. It is also possible to reduce the distance required for deceleration by increasing the torque of the motor M1 or the like, but this also increases the cost.

As described above, in order to improve the performance as much as possible at low cost, it is preferable to provide only one sensor on the path 416 and perform the control as shown in FIG.

FIG. 10 is a flowchart showing control of the intermediate processing tray in the finisher 400, particularly control of sheet bundle discharge by the bundle discharge belt 421. First, as an initial operation before the image forming operation, it is determined whether there is a sheet on the bundle discharge belt 421 (the intermediate processing tray 430) based on the output of the sensor S5 (S12).
1). If there is a sheet on the bundle discharge belt 421, it is determined whether the sheet is the second original sheet (S1).
22). The second original sheet is a thin and rigid sheet used for drafting and the like.

Here, the manual paper feed unit 125 shown in FIG.
When the setting for using is made on the image forming apparatus main body side, the display screen provided on the operation unit 1 of the image forming apparatus main body is
When the "material" key is pressed on this screen, the state shown in FIG. 15C is obtained.

When the second original drawing key is pressed on this screen, it is assumed that the second original drawing sheet is fed from the manual paper feed unit 125, and the image forming apparatus main body sends the finisher 40
When the sheet is transferred to the sheet No. 0, the image forming apparatus main body notifies the finisher 400 of the material information and sheet feeding unit information associated with the sheet.

Thus, the finisher 400 can determine that the sheet on the bundle discharge belt 421 is the second original sheet.

FIG. 15A shows a display screen of the operation unit 1 in the normal standby mode in the copy mode, in which the number of image forming units set by the operation unit 1 and the like are displayed.

If it is determined in step S122 that the sheet is not the second original sheet, the sheet discharge belt 421 is driven to discharge the sheet bundle (S123), and a standby signal is output to the image forming apparatus main body (S126).

If it is determined that the sheet is the second original drawing sheet, an intermediate processing tray overflow signal is output to the image forming apparatus main body (S124). The image forming apparatus main body that has received the intermediate processing tray overflow signal displays "Remove the sheet from the intermediate processing tray." On the operation unit 1.

Then, it waits until there is no more sheet from the bundle discharge belt 421 (intermediate processing tray 430) (S1).
25) When the sheet runs out, a standby signal is output to the image forming apparatus main body (S216).

In step 121, the bundle discharge belt 42
If it is determined that there is no sheet on the printer 1, a standby signal is output to the image forming apparatus main body (S126). In response to a standby signal from the finisher 400, the image forming apparatus main body starts forming an image on a sheet.

After outputting the standby signal in step S126, each of the variables S, N and T is set to 0 (S
127). The variables S and N are variables for monitoring the intermediate processing tray 430 so as not to be overloaded. The variable T is a variable for preventing the sheets on the stack tray 411 from being adversely affected by the static electricity charged to the OHP when the OHP sheet is discharged.

Next, the type information of the material of the sheet discharged from the image forming apparatus main body is received, and it is determined whether or not the sheet is the second original drawing (S128). If it is determined that the original image is not the second original image, the following processing is performed.

First, the sheet received from the image forming apparatus main body is discharged onto the bundle discharge belt 421 (S129), and a weighting count for a variable S described later is performed (S13).
0). Then, the size information of the next sheet to be received is received from the image forming apparatus main body, and it is determined whether or not the width of the sheet already stacked on the bundle discharge belt 421 is different from the width of the next sheet to be received (S131). ).

If the widths of the two sheets are not different, then
It is determined whether or not the setting of the image forming job for the sheet currently being received is the non-staple mode (non-binding output mode) (S132). If the mode is the non-staple mode, the bundle discharge belt 421 is determined in step S129.
It is determined whether or not the sheet discharged above has been fed from the manual feed unit 125 (S133). If the sheet has been fed from the manual sheet feeding unit 125, one is added to the variable T (S134), and it is determined whether or not the variable T has become 2 (S135).

When the variable T becomes 2, that is, when two sheets are continuously fed from the manual paper feed unit 125, the bundle discharge belt 421 is driven to discharge the sheet bundle (S136). ), If the job has not been completed (S15)
6), and return to step S127.

If it is determined in step S133 that the sheet discharged onto the bundle discharge belt 421 is not a sheet fed from the manual sheet feeding unit 125, the variable T is set to 0 (S137), and a step described later is performed. Proceed to S138. Also, when the variable T is not 2 in step S135, the process proceeds to step S138 described later.

Here, the manual sheet feeding section 125 is designed to be able to feed various types of sheets including OHP sheets. OHP sheets are more easily charged with static electricity than ordinary paper. Therefore, even if 30 sheets of ordinary paper are discharged together from the bundle discharge belt 421 to the stack tray 411 without affecting the sheets on the stack tray 411, if only 30 sheets of OHP sheets are discharged together, The sheet on the stack tray 411 may be shifted due to the synergistic effect of weight and static electricity.

Therefore, when two sheets fed from the manual sheet feeding unit 125 to which an OHP sheet may be fed continue, the sheet bundle is immediately discharged to prevent the sheet bundle. I have.

If the width of the sheet stacked on the bundle discharge belt 421 is different from the width of the next sheet to be received in step S131, the flow advances to step S136 to discharge the sheet bundle. In step S132, the mode is not the non-staple mode, that is, the staple mode (the binding discharge mode).
If it is, it is determined whether the variable S has reached 60 or more (S138).

If the variable S is not equal to or greater than 60, that is, less than 60, it is determined whether or not it is a job break based on the presence or absence of a job break signal from the image forming apparatus main body (S140). If it is a job break, the flow advances to step S136 to discharge the sheet bundle.

If it is determined in step S138 that the variable S is equal to or greater than 60, the current stapling is prohibited (S139), and the flow advances to step 136 to discharge the sheet bundle. Prohibition of stapling is released after receiving the delimiter signal.

On the other hand, when it is determined in step S128 that the sheet discharged from the image forming apparatus main body is the second original sheet, the sheet received from the image forming apparatus main body is discharged onto the bundle discharge belt 421 (S141). ), And add 1 to the variable N (S142). Then, a weighting count is performed on the variable S (S143), and it is determined whether or not the variable N becomes 15 (S144).

If the variable N has not become 15, it is determined whether or not the variable S has become 60 or more (S14).
5). If the variable S is not equal to or greater than 60, it is determined whether or not the job is a job break based on the presence or absence of a job break signal from the image forming apparatus main body (S14).
6).

If it is not a job break, the process returns to step S128. If it is a job break, an intermediate processing tray overflow signal is output to the image forming apparatus main body (S147). Accordingly, as described above, the image forming apparatus main body performs a display for removing the sheet on the intermediate processing tray 430.

This is because the second original drawing sheet has a weak stiffness and is not suitable for bundle discharge, and therefore it is preferable to have the user remove it from the intermediate processing tray 430 without discharging the bundle. At this time, the intermediate processing tray overflow signal is used as a signal for activating the display for prompting the image processing apparatus main body.

After step 147, the bundle discharge belt 421
Until the sheet is removed from the (intermediate processing tray 430) (S148), an intermediate processing tray sheet presence signal is output to the image forming apparatus main body (S149).

The image forming apparatus main body does not start the next image forming job while receiving the intermediate processing tray overflow signal and the intermediate processing tray sheet presence signal.

When the variable N becomes 15 in step S144 and when the variable S becomes 60 or more in step S145, it is determined that the sheet stacking amount on the intermediate processing tray 430 has reached the limit amount. An intermediate processing tray overflow signal is output to the forming apparatus body (S15
0), and proceed to step S148. Also at this time, the image forming apparatus main body performs a display for removing the sheet on the intermediate processing tray 430.

When the processing proceeds to the processing after step S129 (that is, in the case of a sheet other than the second original drawing), the aligning plate 412 is adjusted according to the sheet size, and the return roller 417 is rotated clockwise. However, when the process proceeds to the process after step S141 (in the case of the second original sheet), the alignment plate 41 is placed at a position where sheet stacking is not obstructed.
2 is retracted so that the aligning operation is not performed, and the return roller 417 is not driven.

FIG. 20 shows a state on the bundle discharge belt 421 when the second original sheet is discharged.

FIG. 12 is a flowchart of the weighting count in steps S130 and S143. Based on the size information of each sheet received from the image forming apparatus main body, when the sheet length (length in the conveyance direction) is 297 mm or less (S151), 2 is added to the variable S (S15).
2).

The sheet length is longer than 297 mm and 3
If it is less than 64 mm, 3 is added to the variable S (S15
4).

If the sheet length is longer than 364 mm, 4 is added to the variable S (S155).

As described above, by weighting the count value according to the sheet length, when the sheet bundle is discharged, the intermediate processing tray 43 up to the number of sheets suitable for discharging the sheet bundle is used.
In this case, the stacking of the sheets on the intermediate processing tray 430 is enabled when the sheet bundle is not discharged.

FIG. 13 is a control flowchart of the bundle pressing member 420 in the finisher 400.

After the start of copying, the stack tray 411 is controlled to move up and down so that the sensor S10 is turned on. Then, the sheets received from the image forming apparatus main body are bundle-discharged by driving the bundle discharge belt 421 by the forward rotation of the motor M2 (S161).

Next, in step S178, it is determined whether the mode is the staple mode. If the mode is not the staple mode, the bundle holding member 420 is rotated by the reverse rotation of the motor M2 to hold the bundle of sheets on the stack tray 411. The operation is performed (S176). At this time, the bundle pressing member 420 is stopped at the home position shown in FIG. 23, and presses the sheet bundle stacked on the stack tray 411. Whether or not the bundle holding member 420 is located at the home position is determined by detecting the bundle holding member 420 with a bundle holding home sensor (not shown).

Since the bundle pressing member 420 is made of an elastic member, as shown in FIG. 23, it is stationary in a bent state.

Next, the stack tray 411 is lowered (S162), and whether or not the stack tray 411 has reached the lower limit is detected by the lower limit sensor S12 (see FIG. 8) (S163).

On the other hand, if the staple mode has been set in step S178, the flow advances to step 180 to determine whether or not the bundle holding member 420 is located at the retracted position shown in FIG. 24 (ie, a position where the bundle of sheets is not pressed). It is detected by the bundle holding retreat sensor shown in the drawing, and when it is located at the retreat position, the process proceeds to step S162, and when it is not located at the retreat position, the process proceeds to step S181 to rotate to the retreat position.

In step S162, the stack tray 41
1 is lowered and the stack tray 41 is
When 1 does not reach the lower limit, that is, when the lower limit sensor S12 is not turned on, it is detected whether the height sensor S10 is turned off (see FIG. 14) (S16).
4). If the height sensor S10 has not been turned off, the process returns to step S162.

In step 164, the height sensor S10
Is stopped when is turned off, and after a predetermined time,
The stack tray 411 is raised until the height sensor S10 is turned on (see FIG. 15) (S165, 166).
After the height sensor S10 is turned on, the stack tray 411 is continuously raised until a predetermined amount is raised (S167, S168), and stopped (S169).

The motor M5 for raising and lowering the stack tray 411 is a DC motor, and by counting the number of pulses from an encoder provided on the axis of the DC motor, the finisher control unit 401 allows the stack tray 41
1 can be monitored. Also, the motor M5
Is constituted by a stepping motor, and monitoring by counting the input clock is also possible.

In step S163, the stack tray 411
Has reached the lower limit, that is, when the lower limit sensor S12 is turned on, a stacker overflow signal is output to the image forming apparatus (S170), and the operation of the stack tray 411 is stopped (S171). After the completion of the job, the image forming apparatus main body that has received this signal displays “Remove the paper from the stack tray.” On the operation unit 1.

Then, it is determined whether or not there is a job for discharging the next sheet bundle (S172). If there is such a job, the sheet bundle is continuously discharged (S173).

Next, it is determined whether or not the mode is the staple mode (S179). If the mode is not the staple mode, that is, if the mode is the non-staple mode, the process proceeds to step S177.
A bundle holding operation by the bundle holding member 420 is performed.

If the mode is the staple mode in step S179, the flow advances to step S172. Next, the height sensor S
10 is turned off (S174), and when turned off, the stacker overflow signal is turned off (S174).
175).

If the lower limit position is reached during the lowering of the stack tray 411, the job which cannot be stopped at the time of detection of the lower limit (for example, computer) without performing the raising operation of steps S165 and S167. 20
4) is performed for several sheet bundles corresponding to the job received from job No. 4).

As described above, in the present embodiment, when the sheet bundle stacked on the stack tray 411 is stapled, the next sheet bundle is discharged when the uppermost sheet of the stacked sheet bundle is discharged. Because displacement is unlikely to occur,
In the sheet bundle discharging process in the staple mode, the bundle pressing operation by the bundle pressing member 420 is not performed.
The processing time from the start of discharging the sheet bundle to the stop of the stack tray 411 at the predetermined elevating position is reduced.

Here, the vertical position of the stack tray 411 suitable for discharging the sheet bundle will be described. If the distance from the bundle discharge belt 421 to the stacking surface on the stack tray 411 is too large, the stackability of the sheet bundle on the stack tray 411 is poor. In addition, since the leading edge of the sheet while being discharged to the paper discharge roller 415 follows a trajectory as shown in FIG.
The leading end of the sheet abuts on a steeply inclined portion of the stacking surface of the sheet No. 1, and a jam may occur during the conveyance of the sheet discharging roller 415.

Therefore, by controlling the lowering and raising of the stack tray 411 in steps S162 to S169, the distance between the bundle discharge belt 421 and the stacking surface on the stack tray 411 is hardly jammed, and the stackability is improved. Set.

In the present embodiment, the upper surface of the sheet on the stack tray 411 is detected by the height sensor S10. Therefore, if the upper surface of the sheet cannot be detected while the stack tray 411 is descending, the bundle discharge belt 42
It becomes impossible to control the exact distance between the stacking surface 1 and the stacking surface on the stack tray 411.

Therefore, the thickness of the sheet bundle may be estimated and controlled from the number of sheets of the discharged sheet bundle.
The thickness of the sheet varies, and may not be the bundle thickness as estimated.

If a bundle that is thicker than expected is discharged, the distance between the bundle discharge belt 421 and the stacking surface of the stack tray 411 becomes short as described above, and there is a possibility that a jam occurs. For this reason, when the lower limit position is reached while the stack tray 411 is descending, steps S170 to S17 are performed.
Under the control of 3, the stack tray 411 is not lifted and the remaining sheet bundle is discharged. As a result, the distance between the bundle discharge belt 421 and the stacking surface on the stack tray 411 becomes slightly large, and the stacking property on the stack tray 411 may be deteriorated. Since the sheet bundle discharged at this time is the last bundle, even if the stackability is somewhat poor, there is no significant effect.

In this embodiment, the finisher 40
The length of the bundle discharge belt 421 is set to be slightly shorter in order to make the O. 0 compact and low-cost. For this reason, when processing a long sheet such as A4R or A3 size, as shown in FIG. 22, a portion that does not fit on the bundle discharge belt 421 is supported by the stack tray 411.

When the image forming apparatus starts an image forming job in the staple mode, the sensor S11 detects that sheets are stacked on the stack tray 411.
Is detected, the image forming apparatus main body displays, on the operation unit 1, "Please remove the sheet from the stack tray." This is because, when a stapled sheet bundle is stacked on the stack tray 411, the staple portions overlap with each other and the stackability is not very good. Therefore, it is desired to start an image forming job in a state where sheets are not stacked on the stack tray 411 as much as possible. That's why.

However, since the main body of the image forming apparatus is used not only in the copy mode but also in the printer mode, even if the user is not present, the image forming job (staple processing, sheet (Including a bundle discharge process).

In this embodiment, when 30 image forming jobs have been completed continuously in the staple mode,
The image forming job is temporarily interrupted, "Remove the sheet from the stack tray" is displayed on the operation unit 1, and the image forming job is restarted until the sheet is removed from the stack tray 411 and the sensor S11 is turned off. To wait.

In the above embodiment, the sheet processing apparatus provided in the image forming apparatus has been described. However, the sheet processing apparatus of the present invention can be used in various apparatuses that handle sheets other than the image forming apparatus.

[0135]

As described above, according to the present invention,
If the sheet bundle already stacked on the stacking tray has not been subjected to the binding process and the non-binding discharge mode in which the uppermost sheet of the sheet bundle is likely to be displaced is set, the bundle pressing means performs the bundle pressing operation. When the binding discharge mode is set while the sheet bundle already stacked on the stacking tray has been bound and the top sheet is unlikely to be misaligned, while the misalignment can be prevented reliably. By omitting the bundle holding operation by the bundle holding means, the processing time after the binding processing can be shortened, and the next sheet bundle can be discharged to the stacking tray in a short time.

If the bundle conveying means and the bundle pressing means are selectively driven by the same drive source in forward and reverse rotations, the bound sheet bundle is conveyed to the stacking tray by the bundle conveying means. Since the bundle pressing means is not driven later, the preparation for transporting the next sheet bundle is completed in a short time, such as returning the bundle transport means to the position for transporting the next sheet bundle by the driving source. be able to.

By providing such a sheet processing apparatus in an image forming apparatus, the processing speed of the entire image forming apparatus can be increased.

In addition, every time the sheet bundle is conveyed to the stacking tray, when the stacking tray is moved up and down for detecting the stacking amount of the sheet bundle on the stacking tray and setting the position of the stacking tray. After the bound sheet bundle is discharged and stacked on the stacking tray, the stacking tray can be moved up and down without waiting for the bundle pressing operation of the bundle pressing member. Can be started in time.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a basic configuration of an embodiment of the present invention and a conventional image forming apparatus (image forming apparatus main body and finisher <sheet processing apparatus>).

FIG. 2 is a block diagram of a control circuit of the image forming apparatus.

FIG. 3 is a block diagram of an image signal control unit in the control circuit.

FIG. 4 is a diagram showing a configuration of the finisher.

FIG. 5 is a diagram illustrating a sensor and a motor in the finisher.

FIG. 6 is a diagram illustrating a temporary stop position of a bundle discharge lever in the finisher.

FIG. 7 is a diagram illustrating a driving mechanism of an alignment plate in the finisher.

FIG. 8 is a view for explaining a stack tray elevating mechanism in the finisher.

FIG. 9 is a flowchart of driving control of a discharge roller in the finisher.

FIG. 10 is a flowchart illustrating control of an intermediate processing tray (sheet bundle discharge control by a bundle discharge belt) in the finisher.

FIG. 11 is a diagram illustrating a display screen in the image forming apparatus main body.

FIG. 12 is a sub-flowchart of a weight count in the flowchart of FIG. 10;

FIG. 13 is a control flowchart of a stack tray in the finisher.

FIG. 14 is a diagram illustrating a height sensor in the finisher.

FIG. 15 is a diagram illustrating a height sensor in the finisher.

FIG. 16 is a diagram illustrating a state of a sheet in the finisher.

FIG. 17 is a diagram illustrating a state of a sheet in the finisher.

FIG. 18 is a diagram illustrating a state of a sheet in the finisher.

FIG. 19 is a diagram illustrating a state of a sheet in the finisher.

FIG. 20 is a diagram illustrating a state of a sheet in the finisher.

FIG. 21 is a diagram illustrating a state of a sheet in the finisher.

FIG. 22 is a diagram illustrating a state of a sheet in the finisher.

FIG. 23 is a diagram illustrating a home position of a bundle holding member in the finisher.

FIG. 24 is a diagram illustrating a retracted position of the bundle pressing member.

FIG. 25 is a perspective view of an intermediate processing tray in the finisher.

DESCRIPTION OF SYMBOLS 200 Image reader unit 300 Printer unit 400 Finisher 411 Stack tray 412 Alignment plate 415 Discharge roller 417 Return roller 419 Staple unit 420 Bundle holding member 421 Bundle discharge belt 421A Bundle discharge lever 421B Intermediate processing tray loading assistance Board

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yuzo Matsumoto 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 3F054 AA01 AB01 AC02 BA04 BD02 BG02 BG04 BG11 CA11 DA01 3F108 GA02 GB01 HA39 HA44 HA54

Claims (6)

[Claims] 1. A bundle processing means for binding a plurality of sheets sequentially supplied, a staple means for binding a sheet bundle bound by the bundle processing means, and a sheet bundle bound by the bundle processing means to a stacking tray. A bundle conveying means for conveying, and a bundle pressing means capable of performing a bundle pressing operation for pressing a sheet bundle stacked on the stacking tray, binding the sheet bundle by the staple means and by the bundle conveying means to the stacking tray. In a sheet processing apparatus capable of selectively setting a binding discharge mode in which the sheet is conveyed and a non-binding discharge mode in which the sheet is conveyed to the stack tray by the bundle conveyance unit without binding by the stapling unit, the non-binding discharge mode is set. When the binding discharge mode is set, the bundle pressing means causes the bundle pressing means to perform the bundle pressing operation. Sheet processing apparatus characterized by comprising a control means not to perform the bundle pressing operation. 2. The stacking tray is capable of moving up and down with respect to the bundle transporting unit. The control unit is configured to perform the loading operation each time a sheet bundle is transported to the stacking tray by the bundle transporting unit. 2. The sheet processing apparatus according to claim 1, wherein the tray is moved up and down. 3. The sheet processing apparatus according to claim 1, wherein the control unit moves the stacking tray down to detect a stacking amount of a bundle of sheets stacked on the stacking tray. 4. The control device according to claim 2, wherein said control means raises and lowers said stacking tray to set a lifting position of said stacking tray with respect to said bundle transport means. Sheet processing equipment. 5. The sheet processing apparatus according to claim 1, wherein said bundle conveying means and said bundle pressing means are selectively driven by forward and reverse rotations of a same driving source. . 6. An image forming apparatus comprising the sheet processing apparatus according to claim 1.