JP2000301493A - Sheet punch device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a punch hole in the accurate position of a sheet regardless of unevenness in the stop positions of a punch and a die. SOLUTION: A sheet punch device is provided with a drive means to rotate a punch 61 and a die 63 and a drive means is stopped by a detecting signal from a detecting means to detect the notch 75a of a detecting sheet 75. In a so formed sheet punch device, a device is provided to control the drive means such that the punch 61 and the die 63 form a punch hole in the given position of a sheet, based on a time in which after the punch 61 and the die 63 start rotation, a detecting means does not detect the notch part 75a of the detecting sheet 75.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet punching apparatus which is provided in an image forming apparatus such as a copying machine, a printing machine, etc., and perforates a sheet.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. Hei 7-136995 discloses a sheet punching device provided in an image forming apparatus such as a copying machine and a printing machine. In this sheet punching apparatus, a punch and a die provided in the middle of a transport path in which a sheet is transported rotate to punch a punch hole in the sheet,
A detection plate having a notch rotates in conjunction with the punch and the die, and the punch and the die are stopped at predetermined positions by detecting the notch of the detection plate with a home position sensor. Further, the sheet punching device has a detecting means for detecting the sheet in the middle of the conveying path, and based on a detection signal from the detecting means, the sheet punching device is configured to refer to an end face of the sheet on which a punch hole is punched. Controls device operation timing.

[0003]

In the above-described sheet punching apparatus, the punch and the die are stopped at predetermined positions by detecting the notch of the detecting plate by the home position sensor. However, the punch and the die are stopped. The position may vary due to inertia, play, etc. of the punch and the die, and the variation in the stop position of the punch and the die directly results in the variation of the punch hole punching position of the sheet.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet punching apparatus capable of punching a punched hole at an accurate position of a sheet irrespective of a variation in a stop position of a punch and a die.

[0005]

According to a first aspect of the present invention, there is provided a punch and a die which are provided in the middle of a conveying path along which a sheet is conveyed, rotate and punch a punch hole in the sheet. A driving means for rotating the punch and the die, a detection plate which rotates in conjunction with the punch and the die and has a notch, and the punch and the die are detected by detecting the notch of the detection plate. Detecting means for detecting that the user has arrived at the home position,
In the sheet punching apparatus for stopping the driving means in response to a detection signal from the detection means, the punch and the die start rotating from a stop position until the detection means no longer detects the notch of the detection plate. And means for controlling the driving means so that the punch and the die punch a punch hole at a predetermined position of the sheet based on the time.

[0006]

FIG. 2 shows an embodiment of a post-processing apparatus to which the present invention is applied, and FIGS. 1 and 3 show each part of the post-processing apparatus. 1 to 3, 1 is an image forming apparatus such as a copying machine, 2 is a post-processing apparatus that performs post-processing such as punching on a sheet as an image-processed sheet from the image forming apparatus 1,
Reference numeral 3 denotes a discharge roller in the image forming apparatus 1. Inside the post-processing device 2, a switching claw 4 is disposed near the sheet entrance, and the switching claw 4 sequentially feeds the conveying roller 5 in one sheet conveying direction, a sheet punching device 6 as a sheet punching device, and conveying rollers 7, 8. , Discharge rollers 9 and a plurality of bins 10 arranged in multiple stages in the vertical direction.

The bin 10 is held by a helical spiral 11, and the helical spiral 11 is vertically rotated by a drive control unit to move up and down to distribute (sort or stack) the paper from the discharge roller 9. Will be Further, the post-processing device 2 has a tray 12 provided at an upper portion thereof, and the conveying roller 1 is provided between the switching claw 4 and the tray 12.
3. Discharge rollers 14 are arranged in order. An entrance sensor 15 is provided near the upstream side of the switching claw 4.

Here, transport rollers 5, 7, 8, and 13 as transport means for transporting the paper are driven by a DC brushless motor 16 as a drive source, and discharge rollers 9 and 14 as discharge means for discharging the paper are provided. The sheet punching device 6 is driven by a stepping motor 17 as a driving source, and is driven by a stepping motor 18 as a driving source.

The sheet punching device 6 has two punches 61 and 62 and two dies 63 and 64 which are arranged to face each other across the sheet transport path S. Dice 63, 64
Has holes 63a, 64a and taper guides 63b, 64b connected to the holes 63a, 64a and having a wider facing surface side of the dies 63, 64.
b, 64b, the scrap storage box 6 located immediately below
5 is formed so as to surely guide the scrap 66 to the hole 5.

1 and 3, reference numeral 67 denotes a rotating shaft of the dies 63 and 64; 68, a rotating shaft of the punches 61, 62; 69, a home position sensor as a detecting means;
70 is a transmission pulley, 71 is a timing belt, 72, 7
3 is a gear, 74 is a drive pulley integrally attached to the rotating shaft of the stepping motor 18, and 75 is a notch 7
Reference numeral 5a denotes a detection plate, 76 denotes a stay, and 77 denotes a full detection sensor. The timing belt 71 is stretched around a drive pulley 74 and a transmission pulley 70, and the rotational force of the transmission pulley 70 is transmitted to the gears 72 and 73.
The gears 72 and 73 are fixed to rotating shafts 67 and 68, respectively. The empty waste storage box 65 is held by a stay 76,
The fullness detection sensor 77 is attached to the stay 76.

The paper punching device 6 includes transport rollers 5, 7,
The punches 61 and 62 are driven by a stepping motor 18 different from the DC brushless motor 16 for driving the punches 8 and 13, and after punching punch holes in the sheet by the sheet punching device 6.
By increasing the rotation speed of the rotary punch means composed of the dies 63 and 64, the punches 61 and 62 and the dies 63 and 64 are adapted to quickly respond to the next sheet.
Can be returned to the home position at high speed, and it is possible to cope with the image forming apparatus 1 such as a high-speed copying machine.

FIG. 9 shows a control system of the post-processing device 2. Detection signals from the entrance sensor 15, the home position sensor 69, and the fullness detection sensor 77 are input to the CPU 78 as control means via the buffer 79 and the I / O interface 80. The CPU 78 outputs a DC signal according to the input signal.
The brushless motor 16 is connected to the I / O interface 80,
The control is performed via a motor driver 81 and the stepping motors 17 and 18 are connected to the I / O interface 8.
0, control via stepping motor controllers 82 and 83.

Next, the operation of the post-processing device 2 will be described. The image-formed sheet discharged from the image forming apparatus 1 by the discharge roller 3 is carried into the post-processing apparatus 2.
The sheet carried into the post-processing device 2 is supplied to the entrance sensor 15.
The transport path is switched to the tray 12 side or the bin 10 side by the switching claw 4. The sheet whose conveyance path has been switched to the tray 12 side by the switching claw 4 is conveyed by the conveyance roller 13 and discharged to the tray 12 by the discharge roller 14.

The sheet whose conveyance path has been switched to the bin 10 by the switching claw 4 is conveyed by the conveyance roller 5, punched by the sheet punching device 6, conveyed by the conveyance rollers 7 and 8, and discharged. It is discharged to the bin 10 by the roller 9. In this case, the helical spiral 11
Move in the vertical direction and the paper from the discharge roller 9 is distributed to the plurality of bins 10, so that the paper is sorted or stacked.

Here, the CPU 78 controls the transport rollers 5,
The DC brushless motor 16 is controlled by the I / O interface 80 and the motor driver 81 so that the speed at which the paper is conveyed by the image forming apparatus 1 is substantially the same as the speed at which the paper is conveyed by the paper discharge rollers 3 from the image forming apparatus 1. Control over.

When a certain period of time has passed since the sheet was conveyed to the sheet punching device 6 and the sheet passed through the entrance sensor 15, the stepping motor 18 was operated and the drive pulley 74 attached to the stepping motor 18 was rotated. The rotational force of the driving pulley 74 is applied to the timing belt 7.
1 to the transmission pulley 70. Transmission pulley 7
The torque of 0 is transmitted to the gears 72, 73 and the gears 72, 7
3 rotates, and the rotation of the gears 72 and 73 causes the rotation shaft 6 to rotate.
7, 68 are rotated to form two sets of punches 61, 62 and a die 6
3, 64 rotate.

As shown in FIG. 4, the sheet 84 is
1 and 62 and the dies 63 and 64.
As shown in (a), the punches 61, 62 and the dies 63, 6
4 rotates and the dies 63, 64 as shown in FIG.
When the punches 61 and 62 are inserted into the holes 63a and 64a, a punch hole is formed in the sheet 84. At this time, the CPU 78 sets the punches 61 and 62 and the dice 63 and 64
The stepping motor 18 is driven by the I / O so that the linear speed of the holes (blades) 63a and 64a of the
Control is performed via the O interface 80 and the stepping motor control device 83. As a result, the shape of the punch holes of the paper 84 becomes the same as the shapes of the holes 63a and 64a of the dies 63 and 64, and the paper 84 does not suffer from burrs or tears.

The time from when the paper 84 passes through the entrance sensor 15 to when the punches 61 and 62 and the dies 63 and 64 start rotating can be set arbitrarily. Punch holes can be formed. The punches 61 and 62 and the dies 63 and 64, which have finished punching holes in the paper 84, are further rotated as shown in FIG.
When the home position sensor 69 detects the notch 75a of the detection plate 75 by the detection signal from the step 9, the stepping motor 18 is stopped via the I / O interface 80 and the stepping motor control device 83, so that the punches 61, 62 The dice 63 and 64 are stopped. The above-described series of operations is performed each time one sheet is discharged from the image forming apparatus 1.

The paper punching device 6 repeatedly executes the punching operation, and the scrap 66 falls into the scrap storage box 65 as shown in FIG.
When a certain amount is accumulated in the inside 5, the full detection sensor 77 detects this, and the CPU 78 turns on a light emitting diode (not shown) according to a detection signal from the full detection sensor 77, and the extraction waste 66 in the extraction waste storage box 65 becomes full. The operator is notified that there is something.

The empty waste storage box 65 is configured to be detachable from the paper punching device 6, and it is determined that the empty waste 66 in the empty waste storage box 65 is full.
In this state, the scrap storage box 65 can be pulled out of the sheet punching device 6 and the scrap 66 in the scrap storage box 65 can be processed in a state where it is detected by the lighting of the light emitting diode.

The post-processing apparatus 2 distributes sheets discharged from the image forming apparatus 1 onto bins 10 arranged in multiple stages, and includes a sheet processing apparatus 6 provided with a sheet punching apparatus 6 for punching the sheets. A sheet punching device 6 is arranged on the front side of the bin 10 and punches punches one by one in a sheet by rotating punches 61 and 62 and dies 63 and 64 facing each other. Figure 4
As shown in FIG. 7, a projection 85 is provided at the center of the blades at the tips of the punches 61 and 62 to separate the scrap 66 generated when punching holes from the paper 84. From the paper 84 to the dice 63,
64 can be pushed into the
6 are completely separated to form holes 63a, 63a,
64a, the scraps 66 do not adhere to the sheet 84 and are not discharged, and a good perforated sheet can be obtained.

Next, FIG. 5 shows the control of the sheet punching device 6 after a predetermined time has passed since the sheet 84 is conveyed to the sheet punching device 6 and the rear end of the sheet 84 passes through the entrance sensor 15. This will be described in detail based on the timing charts and the flowcharts shown in FIGS. The CPU 78
When a certain period of time has elapsed since the rear end of the sheet 84 has passed the entrance sensor 15 according to an input signal from the entrance sensor 15, the stepping motor 18 starts rotating at a low speed (low set speed). The CPU 78 clears the time measurement counter simultaneously with the start of the low-speed rotation (operation start) of the stepping motor 18 and causes the time measurement counter to start measuring time.

Next, the CPU 78 determines whether or not the home position sensor 69 has stopped detecting the cutout portion 75a of the detection plate 75 based on an input signal from the home position sensor 69, and When the notch 75a is no longer detected, by reading the value of the time measurement counter at this time, the home position sensor 69 detects the notch of the detection plate 75 from the time when the stepping motor 18 starts low-speed rotation. The time t until the detection of the part 75a is stopped is obtained.

Next, the CPU 78 determines the value of the time measurement counter (the time from when the stepping motor 18 starts low-speed rotation to when the home position sensor 69 no longer detects the cutout portion 75a of the detection plate 75). t)
From the time when the stepping motor 18 starts low-speed rotation to the time when the punches 61 and 62 coincide with the holes 63a and 64a of the dies 63 and 64, that is, as shown in FIG. A predetermined setting speed suitable for punching a punched hole in a sheet, for example, as shown in FIG. 5, so that the time until the holes 63a and 64a of the punches 61 and 62 and the dies 63 and 64 reach the punching position becomes constant. An acceleration start point for accelerating the stepping motor 18 to a predetermined high speed is determined.

For example, the CPU 78 determines the value of the time measurement counter (from the time when the stepping motor 18 starts rotating at a low speed, the home position sensor 69 detects the detection plate 75).
If the time t until the notch portion 75a is no longer detected is smaller than the predetermined value, the acceleration start point is delayed, and conversely, the value of the time measurement counter (the stepping motor 18 starts rotating at a low speed) If the time t) from the time when the home position sensor 69 stops detecting the cutout portion 75a of the detection plate 75 to the time when the home position sensor 69 stops detecting the time t) is larger than a predetermined value, the acceleration start point is advanced.

The CPU 78 keeps the speed of the stepping motor 18 after accelerating it from the acceleration start point to a predetermined set speed. Thus, the punch 61,
The time until the point 62 reaches the perforation position corresponding to the holes 63a, 64a of the dies 63, 64 is defined as the stop position before starting the low-speed rotation of the stepping motor 18, that is,
The home position sensor 69 is provided with the notch 7 of the detection plate 75.
Regardless of the position at which the stepping motor 18 is stopped by detecting 5a, the same can always be achieved,
A punch hole can be formed at an accurate position on the sheet regardless of the stop position of the stepping motor 18.

The sheet punching device 6 includes punches 61 and 62 and dies 63 and 64 that are provided in the middle of a transport path S through which a sheet 84 as a sheet is transported and rotate to punch a hole in the sheet. 61, 62 and die 6
A stepping motor 18 as driving means for rotating the punches 61 and 62 and the dies 6
The punches 61 and 62 and the dies 63 and 64 come to the home position by detecting the detection plate 75 having the notch portion 75a and the notch portion 75a of the detection plate 75, which are rotated in conjunction with the detection plates 75 and 64. A home position sensor 69 as a detecting means for detecting that the driving means 18 is stopped by a detection signal from the detecting means 69. After the rotation is started from the stop position, the detecting means 69 moves the notch 75 of the detecting plate 75
The driving means 18 is driven by the punches 61 and 62 and the dies 63 and
Is provided with the CPU 78 as a means for controlling the punch holes to be punched at predetermined positions of the sheet, so that the punch holes can be punched at the correct positions of the sheet irrespective of variations in the stop positions of the punch and the die.

In the sheet punching device 6, the punches 61 and 62 and the dies 6 are changed by changing the acceleration start point.
In the other embodiment of the present invention, in the sheet punching device 6, the CPU 78 controls the value of the time measurement counter (stepping motor). As shown in FIG. 8, the stepping motor 18 is changed from a low speed to a high speed based on a time t) from the time when the motor 18 starts low-speed rotation to the time when the home position sensor 69 stops detecting the cutout portion 75a of the detection plate 75. How to accelerate to stepping motor 1
8 is changed so that the time from the start of the low-speed rotation of the punch 8 to the point at which the punches 61 and 62 reach the punching positions coincident with the holes 63a and 64a of the dies 63 and 64 is constant. The same effect is obtained.

[0029]

As described above, according to the first aspect of the present invention, it is possible to punch a punch hole at an accurate position on a sheet irrespective of variations in the stop positions of the punch and the die.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a part of an embodiment of a post-processing apparatus to which the present invention is applied.

FIG. 2 is a sectional view showing the post-processing apparatus.

FIG. 3 is a perspective view showing a part of a sheet punching device in the post-processing device.

FIG. 4 is a diagram showing each operation state of a part of the paper punching device.

FIG. 5 is a timing chart showing the operation timing of the paper punching device.

FIG. 6 is a flowchart showing an operation flow of the sheet punching device.

FIG. 7 is a flowchart showing another operation flow of the paper punching device.

FIG. 8 is a timing chart showing the operation timing of the embodiment of the present invention.

FIG. 9 is a block diagram showing a control system of the paper punching device.

[Explanation of symbols]

 Reference Signs List 6 paper punching device 84 paper S transport path 61, 62 punch 63, 64 dice 18 stepping motor 75 detecting plate 75a notch 69 home position sensor 78 CPU 78

Claims (1)

[Claims] 1. A punch and a die which are provided in the middle of a conveying path on which a sheet is conveyed, rotate and punch a punch hole in the sheet, driving means for rotating the punch and the die, and the punch and the die. A detecting plate that rotates in conjunction with the notch and has a notch, and a detecting unit that detects that the punch and the dice have reached the home position by detecting the notch of the detecting plate; In the sheet punching device for stopping the driving means in response to a detection signal from the punch, the punch and the die start rotating from a stop position until the detecting means no longer detects the cutout portion of the detection plate. And a means for controlling the driving means so that the punch and the die punch a punch hole at a predetermined position of the sheet based on the driving means. Punch apparatus.