JPH10324447A - Paper sheets post-processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deterioration of a blade tip in a short time due to the engagement of a punch and a dies with each other, and to prevent the occurrence of positional displacement of a punched hole. SOLUTION: A punch unit 21 is provided with a punch 23 and a dies 24 opposite to the punch 23 in relation to a paper sheet passage. The punch 23 is provided with a detecting plate 42 having a notch part 42a, and a home position sensor 41 detects the notch part 42a so as to obtain the home position. At the time of initial operation, the punch 23 is reversely rotated to a position in this side of an engagement position with the dies 24, and continuously, the punch 23 is rotated in the normal direction till the notch part 42a faces to the home position sensor 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper discharge section of an image forming apparatus such as a copying machine or a printer, which receives paper discharged from the paper discharge section of the image forming apparatus and performs various post-processing. The present invention relates to a sheet post-processing apparatus, and more particularly to a sheet post-processing apparatus having a punching function.

[0002]

2. Description of the Related Art A paper post-processing apparatus is connected to a paper discharge section of an image forming apparatus such as a copying machine or a printer and receives paper discharged from the paper discharge section of the image forming apparatus and performs various post-processing. A paper post-processing apparatus for punching filing holes in paper has been widely proposed. The above-mentioned sheet post-processing apparatus having a punching function is provided with a rotary punch unit in the sheet transport path, and is configured to be capable of punching holes without obstructing the transport of the sheet. More specifically, the rotary-type punch unit includes a punch and a die having an engagement hole that meshes with the punch. Face to face, punch holes in the paper.

[0003]

The above-mentioned punch unit is provided with a home position sensor for detecting the home position of the punch and the dice, and the punch and the dice are at the home position during standby. Generally, when the power is turned on, a so-called initial operation is performed, and even if the punch and the dice are not at the home position, they are returned to the home position again. Here, when performing the initial operation, if the punch and the die are rotated once, there is a problem that the punch and the die are engaged without paper and the cutting edge of the punch is quickly deteriorated. Further, conventionally, even when the front door of the apparatus main body is opened, the initial operation is not performed when the punch unit is at the home position, but is performed only when the punch unit is not at the home position. In this case, since the punch unit can be touched, there is a possibility that the position of the punch hole to be punched in the sheet is shifted.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet post-processing apparatus capable of preventing the edge of a punch from deteriorating in a short period of time due to meshing of a punch and a die, and preventing displacement of a punch hole. It is.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to provide a sheet post-processing apparatus having a rotary type punch unit for punching filing holes for image-formed sheets discharged from a sheet discharge section of an image forming apparatus. , A home position sensor for detecting a home position of a punch and a die forming a punch unit, and a control function of performing an initial operation of rotating the punch and the die within a non-meshing rotation range of the punch and the die. It is solved by means. In the first means, in the first means, when the punch and the die are at the home position, the initial rotation direction at the time of the initial operation is the opposite direction to that when punching a punch hole, and the first rotation direction is a predetermined amount. Thereafter, the second means for performing control to stop in the home position by rotating in the same direction as when punching a punch hole is solved. In the second means, the speed at which the punch and the die are returned to the home position during the initial operation is set to the same speed as the speed at which the punch and the die return to the home position when punching a hole in the sheet. 3
It is solved by the means of. The above object is achieved by a first means, wherein the home position sensor is configured to detect a cutout portion of a detection plate provided coaxially with the punch. The above object is achieved by the first means, wherein the initial operation is performed by the fifth means which is also executed when the front door of the apparatus main body is opened. The above problem is solved by a fifth means in which the initial operation is executed when the opened front door is closed again.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a sheet post-processing apparatus according to an embodiment of the present invention. A sheet post-processing device 10 is connected to the downstream side (later stage) of the copying machine (image forming apparatus) 1. The sheet post-processing apparatus 10 includes a switching claw 11, an upper transport path 12, a lower transport path 13, upper transport rollers 14, 15, a discharge tray 16, lower transport rollers 17, 18, 19, a sorter bin 20, a punch unit 21, Pull unit 2
2, entrance sensor 25, discharge roller 28, entrance roller 2
9. Punch hole detection sensor (punch hole check sensor)
30, spiral cam 31 for raising and lowering sorter bin 20
Etc. are provided. In such a configuration, the copying machine 1
Is configured to feed a sheet on which an image has been formed to a sheet post-processing device 10 provided at a subsequent stage by a sheet discharging roller 2 provided in a sheet discharging unit. The sheet fed into the sheet post-processing device 10 is fed into the punch unit 21 by the entrance roller 29.
The paper fed into and carried into the switching claw 11 can be switched by the switching claw 11 to the upper transport path 12 and the lower transport path 13 side. The sheet directed to the upper transport path 12 is guided to the upper discharge tray 16 by the upper transport rollers 14 and 15. On the other hand, the sheet directed to the lower transport path 13 is transported to the discharge roller 28 by the lower transport rollers 17, 18 and 19, and is guided to the movable sorter bin 20. The punch unit 21 can punch a hole without stopping the sheet being conveyed.

FIG. 2 is a detailed block diagram of the punch unit. As shown in FIG. 2, the punch unit 21 includes a punch 23, a die 24 facing the punch 23 across the sheet path, and a drive motor (not shown) for operating the punch 23 and the die 24. ing. The transported sheet is transported to the punch unit 21 by the transport rollers 29 and 30, and the trailing edge is detected by the entrance sensor 25. After a lapse of a predetermined time from the detection of the trailing edge of the sheet by the entrance sensor 25, the drive motor starts operating, and the punch 23 and the die 24 are moved in opposite directions (the punch 23 is in the a direction and the die 24 is in the b direction). By rotating the paper at the same speed as the paper transport speed, a punch hole is formed at a predetermined position on the paper. The punch 23 and the die 24 that have finished punching at a predetermined position are further rotated, and the home position sensor 41 of the punch unit 21 (see FIG. 5).
, And both stop at a predetermined position. In the present embodiment, a stepping motor (not shown) is used as a drive motor so that position and speed control can be performed. Below the punch unit 21, a collection box 26 for collecting the punched and dropped paper pieces 27 is provided.

FIGS. 3 (a), 3 (b) and 3 (c) are explanatory views showing the positional relationship between a punch and a die in a punching operation step of a punch unit. FIGS. 4 (a), 4 (b) and 4 (c) are the same. FIG. 4 is an explanatory diagram showing a positional relationship between a punch and a sheet. The punching operation will be described with reference to FIGS. As previously mentioned,
Sheet P discharged from sheet discharge roller 2 of image forming apparatus 1
Is transported to the sheet post-processing device 10. The sheet P conveyed to the sheet post-processing device 10 passes through the entrance sensor 25 and is conveyed to the punch unit 21 by the conveyance roller 29. When a predetermined time passes after the rear end of the sheet passes through the entrance sensor 25, the sheet P The stepping motor of FIG.
The punch 23 is rotated clockwise and the die 2
4 rotates counterclockwise. The sheet P is transported between the punch 23 and the die 24 of the punch unit 21, and the punch 23 and the die 24 rotate (see FIGS. 3 and 4A), and the hole 24 a of the die 24 meshes with the punch 23. At this time (see FIGS. 3 and 4B), punching is performed. After the punching, the punch 23 and the die 24 are separated, and the sheet P on which the punch holes are formed is conveyed downstream (see FIGS. 3 and 4C). As described above, after a certain period of time after the paper P passes through the entrance sensor 25, the punch 23 and the dice 24 rotate and mesh with each other, so that it is possible to punch the paper P at a predetermined position. In addition, the time from when the sheet P passes through the entrance sensor 25 to when the punch 23 and the die 24 start rotating can be set arbitrarily, whereby punching at an arbitrary position on the sheet P can be performed. It becomes possible.
The sheet P punched by the punch unit 21 passes through the transport roller 30 and is switched by the switching claw 11 to the discharge tray 1.
The transport direction can be switched to six directions or the sorter bin 20 direction. As described above, the paper P switched to the discharge tray 16 is discharged to the discharge tray 16 by the upper transport rollers 14 and 15, and the paper P switched to the sorter bin 20 is transferred to the lower transport rollers 17 and 15. The paper is conveyed to discharge rollers 28 by 18 and 19 and discharged to the sorter bin 20. Punch 2 after punching holes in paper P
3. The die 24 further rotates, and both stop at a predetermined position (a home position described later). The above series of operations is performed for each sheet discharged by the copying machine 1. Dumps (paper pieces 27) of the paper P punched by the punch 23 and the die 24 fall into the hole 24a of the die 24, and further fall out of the die 24 by the double-sided tapered guide portion of the die 24. It falls into the collection box 26 provided in the lower part.

As described above, the sheet P discharged from the copying machine 1 is fed into the sheet post-processing device 10 by the conveying roller 29, the trailing edge of the sheet is detected by the entrance sensor 25, and is punched after a predetermined time. You. Further, the sheet is conveyed by the conveying roller 30 and conveyed by the switching claw 11 in each conveying direction.

FIG. 5 is a diagram showing the punch unit and its surroundings in a state where the punch and the die are at the home position. The punch 23 is provided on the punch 23 side of the punch unit 21.
A home position sensor (photo sensor) 41 for detecting the home position is provided. In addition, the punch 23
And the dice 24 are linked, so if the home position of the punch 23 is detected, the home position of the dice 24 can also be detected indirectly. A disc-shaped detection plate 42 is fixed to the shaft of the punch 23, and when the punch 23 makes one rotation, the detection plate 42 also makes one rotation. The detection plate 42 is formed with a notch 42a having a certain width so that the home position sensor 41 can detect at a certain angle (position) of the punch 23. By detecting the position sensor 41, the drive motor for operating the punch 23 and the die 24 is controlled, and the punch 23 and the die 24 are stopped at a predetermined location (home position).

When the punch unit 21 is touched from the outside, such as when the power is turned on or when the front door of the apparatus body is opened, the notch 42a has a width in the circumferential direction. Even if it is misaligned, if the width of the notch 42a is not large, the home position is detected as the home position by the home position sensor 41, and a punch position shift occurs. As means for solving this, the initial operation of the punch unit will be described below. 6A and 6B are explanatory diagrams showing the initial operation of the punch unit. FIG. 6A shows the rotation direction of the punch in the first step, and FIG. 6B shows the rotation direction of the punch in the second step. The initial operation of the punch unit 21, which is an operation for positioning the punch 23 and the die 24 at the home position, can be touched from the outside when the power is turned on or when the front door of the apparatus body is opened. This is done only when possible. When the front door is opened and there is no possibility of being touched from outside (specifically, for example, when the front door is closed thereafter), the state of the home position sensor 41 is checked.
As shown in FIG. 6A, if the punch 23 is at the home position, in other words, if the notch 42a of the detection plate 42 is detected by the home position sensor 41, first, as a first step, the punch is executed. 23 (and the detection plate 42) is rotated in a direction B (clockwise), which is a direction opposite to the rotation direction of the operation of punching a sheet. The amount of rotation is controlled to a certain range before the punch 23 and the die 24 engage with each other by controlling the stepping motor. Next, as a second step, as shown in FIG. 3B, the punch 23 is moved in the C direction (counterclockwise direction) which is the same direction as the rotation direction of the operation of driving the stepping motor to punch a hole in the sheet. Rotate. When the home position sensor 41 detects the notch 42a of the detection plate 42, the stepping motor is stopped and the punch 23 is stopped.
Stop the rotation of. The rotation speed when rotating the punch 23 in the direction of arrow C in the second step is controlled so as to be the same speed as when a punch hole is formed at a predetermined position on the sheet, that is, during normal operation. In this way, after the normal punching operation, the home position sensor 41
Thus, the same position as that at which the notch 42a of the detection plate 42 is detected and stopped can be obtained, thereby further preventing displacement.

In this embodiment, the example in which the detection plate 42 is provided on the punch 23 side has been described. However, the detection plate 42 and the home position sensor 41 may be provided on the die 24 side.

Next, the initial operation of the punch unit according to the embodiment of the present invention will be described. FIG. 7 is a flowchart showing the contents of the initial operation of the punch unit according to the embodiment of the present invention. The initial operation of the punch unit 21 in the present embodiment is as described above, but will be described again with reference to FIG. First, it is determined whether or not an initial operation is required (at power-on or whether a front door of the apparatus body is opened) (S1).
YES), and the home position sensor 41 detects whether the punch 23 and the die 24 are at the home position (S2). If it is at the home position (YES in S2), the punch 23 and the die 24 are reversed by rotating the drive motor (stepping motor) of the punch unit 21 in the reverse direction (rotation in the direction opposite to the normal punch operation) (FIG. a) Rotation in the B direction) (S3). Then, it is determined whether or not the punch 23 and the die 24 have rotated by a predetermined amount (S4). Here, the fixed amount is an amount within a range where the two do not mesh as described above, and is performed by pulse control of the stepping motor. As shown in FIG. 6B, if the stepping motor is rotated in the reverse direction by a predetermined amount (YES in S4), the stepping motor is rotated forward (rotation during normal punching operation) (S4).
5). Then, it is determined whether or not the punch 23 and the die 24 have reached the home position by the forward rotation of the stepping motor (S6). If the home position is detected by the detection by the home position sensor 41 (YES in S6), the stepping motor is turned on. It stops (S7) and ends the initial operation.

In the case of NO in S1, the initial operation is terminated because there is no possibility that the punch unit 21 is touched from the outside and shifted, not when the power is turned on or when the front door of the apparatus body is opened. I do.

If NO in S2, the notch 42a is not detected by the home position sensor 41, so the process proceeds to S5, and the stepping motor is rotated forward (rotation during normal punching operation).

In the above-described embodiment, the tip of the punch 23 is prevented from hitting the die 24 during the initial operation, so that the cutting edge of the punch 23 is prevented from being deteriorated early and its life is extended. be able to. As a result, accurate and clean punch holes can be formed. Further, in the above-described embodiment, the initial operation is performed even when the door of the apparatus main body is opened. Therefore, it is possible to prevent a problem caused by touching the punch unit 21, for example, to prevent a displacement of a punch hole. it can. According to the fourth aspect of the present invention, the punch 2 is operated during the initial operation.
Since the speed at which the die 3 and the die 24 are returned to the home position is set to the same speed as the speed at which the punch 23 and the die 24 return to the home position when punching a hole in the sheet,
Since the stepping motor is stopped at the same position as in the normal punching operation and at the same speed, the amount of movement due to inertia can be made the same, and the displacement of the punch hole can be further prevented.

[0017]

According to the first and second aspects of the present invention, the tip of the punch is prevented from hitting the die during the initial operation, thereby preventing early deterioration of the cutting edge of the punch and shortening the life thereof. Can be extended. as a result,
Accurate and beautiful punch holes can be formed. According to the third aspect of the present invention, since the initial operation is performed even when the door of the apparatus body is opened, it is possible to prevent a problem caused by touching the punch unit, for example, a displacement of the punch hole beforehand. According to the invention as set forth in claim 4, the speed at which the punch and the die are returned to the home position during the initial operation is set to the same speed as the speed at which the punch and the die return to the home position when punching a sheet. Since it is stopped at the same position as in the normal punching operation and at the same speed, the amount of movement due to inertia can be made the same, and the displacement of the punch hole can be further prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a sheet post-processing apparatus according to an embodiment of the present invention.

FIG. 2 is a detailed configuration diagram of a punch unit.

FIG. 3 is an explanatory diagram showing a positional relationship between a punch and a die in a punching operation process of a punch unit.

FIG. 4 is an explanatory diagram showing a positional relationship between a punch and a sheet in a punching operation process of a punch unit.

FIG. 5 is a diagram illustrating a punch unit and a periphery thereof in a state where a punch and a die are at a home position.

FIG. 6 is an explanatory diagram showing an initial operation of the punch unit.

FIG. 7 is a flowchart showing details of an initial operation of the punch unit according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 21 Punch unit 23 Punch 24 Dice 41 Home position sensor 42 Detection plate 42a Notch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yukitaka Nakazato 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Kenji Yamada 1-3-6 Nakamagome, Ota-ku, Tokyo Stock (72) Inventor Yoshihiko Nakayama 2-2-13 Nishiki, Naka-ku, Nagoya City, Aichi Prefecture Ricoh Elemex Co., Ltd.

Claims (4)

[Claims] 1. A sheet post-processing apparatus comprising a rotary type punch unit for punching filing holes for an image-formed sheet discharged from a sheet discharge unit of an image forming apparatus, wherein the punch unit is constituted. Paper post-processing, comprising a home position sensor for detecting a home position of the punch and the die, wherein the punch and the die are rotated within a non-meshing rotation range of the punch and the die to perform an initial operation. apparatus. 2. The apparatus according to claim 1, wherein when the punch and the die are at the home position, the initial rotation direction at the time of the initial operation is opposite to the direction at the time of punching a punch hole, and is rotated by a fixed amount in the opposite direction. The sheet post-processing apparatus is controlled to rotate in the same direction as when punching a punch hole and stop at a home position. 3. The sheet post-processing apparatus according to claim 1, wherein the initial operation is performed when the front door of the apparatus main body is opened and closed again. 4. The speed according to claim 2, wherein the speed of returning the punch and the die to the home position during the initial operation is set to the same speed as the speed of returning the punch and the die to the home position when punching a sheet. A sheet post-processing device characterized by the following.