JP3217199B2 - Paper punching device and paper processing device - Google Patents

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 and a sheet processing apparatus which are provided in an image forming apparatus such as a copying machine or a printing machine and which punches discharged sheets. .

[0002]

2. Description of the Related Art Conventionally, in some copying machines and printers, a stapling apparatus for binding a plurality of sheets discharged from an image forming apparatus, and a sheet punching apparatus (punching apparatus) for punching holes in the sheets. Is used. In a type of sheet punching device of this sheet post-processing device, a punch hole is punched in a sheet by inserting a tip end surface of a punch fixed to a rotating shaft into a hole of a die fixed to another rotating shaft. There is known a rotary paper punch having such a configuration.

In the case of this rotary paper punch, it is necessary that the blades of the rotating punch and the die engage with each other accurately, and a gear for rotating each rotating shaft of the punch and the die. Also, a mechanism for eliminating gear backlash is required. As a method of eliminating the backlash of the gear, there has been conventionally known a method in which two gears are overlapped, the position of the tooth tip is slightly shifted, and the backlash of the gear is absorbed by utilizing the friction of the meshing portion of the gear. ing.

[0004]

However, as described above, the two gears having the same tooth profile are slightly shifted from each other to absorb the backlash with the mating gear, so that the two gears overlap each other. In the case where the accuracy of one of the gears is low and eccentric rotation or the like is caused, the load at the time of the rotation may become extremely large.

For this reason, when the backlash of only a part of the rotation operation is absorbed by using this method, if the two gears are adjusted at the position where the backlash is to be absorbed,
At other positions where there is no problem even if there is backlash, there is a possibility that the rotational load becomes large, and there is a problem that the margin of the rotational drive unit is not an unnecessary position for measures against backlash.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to eliminate backlash in only a part of a structure to be rotated and to have backlash in other regions. By providing a rotational operation transmitting means with a small rotational load and using this for the rotational connection part of the rotating shaft of the paper punching device, eliminating only the backlash at the position where the leading end of the punch and the hole of the die engage with each other, A sheet punching device capable of accurately engaging a punch and a blade of a die without applying a useless load to a rotary connecting portion, and a sheet punching device having the sheet punching device in a sheet transport path.
A paper processing device is provided.

[0007]

According to the first aspect of the present invention,
In a sheet punching device for punching a sheet by inserting a tip end surface of a punch fixed to a rotating shaft into a hole of a die fixed to another rotating shaft, the rotating shaft of the punch and the die Are connected by gears of the same shape provided at one end thereof, and a sector gear having the same tooth shape is fixed to one of the gears, and the tooth portion of the sector gear is the tooth of the punch. The tip surface is provided at a position where it engages with the other gear at a certain angle before and after the position where it is inserted into the hole of the die. According to a second aspect of the present invention, there is provided a sheet processing apparatus having a sheet conveying path.
A paper punching device according to claim 1,
Arrange in the paper transport path to stop the paper being transported.
It is characterized by performing a punching process.

[0008]

According to the present invention, the rotary shafts of the punch and the die are connected by gears of the same shape provided at one end thereof, and the one of the gears has the same tooth profile as the sector gear. Is fixed, and the tooth portion of the sector gear is provided at a position meshing with the other gear at a fixed angle before and after the position where the tip end surface of the punch is inserted into the hole of the die. There is no backlash only at a certain angle in the front-rear direction at the position where the leading end surface of the punch is inserted into the hole of the die, and an increase in rotational load at other positions caused by the use of the two-gear is avoided.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1, a copy sheet P discharged from the image forming apparatus 1 is carried into a sheet post-processing apparatus 2, and a plurality of copy sheets P provided at predetermined intervals in the sheet post-processing apparatus 2 as shown in FIG. It is transported between the lower entrance guide plate 3 and the upper entrance guide plate 4 having a shape in which inclined portions are connected.

As shown in FIG. 2, above the entrance upper guide plate 4, sheet detecting means (entrance sensor 8) having a rotatable lever 7 is provided. The lever 7 is disposed so as to extend to the sheet insertion position of the sheet transport path formed by the above. In addition, the entrance lower guide plate 3 is provided with a pressing member 5 for guiding the copy sheet P along the direction of the entrance upper guide plate 4, and the copy sheet P conveyed between the respective guide plates is Presser member 5
Thus, the copy paper P is transported while being pressed against the branch claw 6 for switching the transport direction, and is transported by the transport rollers 9 to the paper punching device 10.

When the passage of the rear end face of the copy paper P is detected by the entrance sensor 8, after a predetermined time has passed,
The drive motor 20 which is the drive unit of the sheet punching device 10 starts rotating. When the drive motor 20 is rotated, as shown in FIG. 3, the drive gear 21 connected by the timing belt 22 is rotated, and the driven gear 23 meshing with the drive gear 21 is rotated in the direction of the arrow.

A driven gear 23 is attached to an end of the rotating shaft 12 to which the die 14 is fixed, and a connecting gear 24 attached to an end of another rotating shaft 11 to which the punch 13 is fixed. The driven gear 23 fixed to the connecting gear 24
And the sector gear 25 having the same tooth profile as the above.

Thus, after a predetermined time from the detection of the trailing edge of the sheet by the entrance sensor 8, the driven gear 23, the connecting gear 24 and the sector gear 25 connected to each other
The rotating shafts 11 and 12 of the sheet punching device 10 rotate in the directions indicated by arrows in FIG. 3, respectively, and the punch 13 and the die 14 fixed to these rotating shafts 11 and 12 rotate.

Here, the connecting gear 24 and the sector gear 25 are
The gears are fixed so that the positions of the tooth tips can be shifted from each other, and by adjusting the positions of the tooth tips of the respective gears, the backlash at the connection between the gears 24 and 25 and the driven gear 23 can be reduced. It can be set to “0”.

The connecting gear 24 and the sector gear 25 are
As shown in FIG. 4, the toothed portion of the sector gear 25 is engaged with the driven gear 23 only at a certain angle before and after the position where the leading end surface of the punch 13 is inserted into the hole of the die 14. The fixed positional relationship is set. Accordingly, in a state where the punch 13 and the die 14 are in a positional relationship other than the above, the toothed portion of the sector gear 25 is located at a position separated from the driven gear 23 and is connected to the driven gear 23. Only the gear 24 meshes, and the respective rotating shafts 11 and 12 are rotated.

Therefore, according to the present embodiment, each rotating shaft 1
By the rotation of the punches 1 and 12, the blade at the tip of the punch 13 is inserted into the hole of the die 14 while sandwiching the copy sheet P, and a punch hole is punched at a predetermined position of the conveyed copy sheet P. The backlash between the driven gear 23 and the coupling gear 24 from immediately before to immediately after becomes “0”, and the punch 13
The die 14 and the die 14 are accurately inserted without causing displacement due to backlash. Further, after the punching of the punch holes in the copy paper P, the driven gear 23 rotates by meshing only with the coupling gear 24, thereby causing a backlash between the two gears and reducing the rotational load between the two gears.

As shown in FIG. 1, the copy sheet P having the punch holes punched by the sheet punching apparatus 10 is transported by the transport rollers 9 into bins 19 disposed in the sheet post-processing apparatus 2.
Ejected above and aligned.

On the other hand, as shown in FIG. 2, the punch scum 16 generated by punching a punch hole in the copy paper P falls into a scum storage box 15 disposed below the dice 14 of the paper punching device 10. Collected.

[0019]

As described above, according to the present invention,
Only in the vicinity of the position where the leading end face of the punch is inserted into the hole of the die, the backlash of the gear of the driving unit is “0”.
By adjusting the gear train so that the rotation load is increased, it is possible to avoid an increase in the rotational load at other positions caused by the use of the two gears. The positional displacement at the time can be eliminated without causing useless load. Further, since the maximum load position applied to the drive motor is fixed, the selection of the drive motor is facilitated, and the margin of the drive motor can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a sheet punching device of the present invention.

FIG. 2 is a sectional view showing a configuration of a sheet punching device of the present invention.

FIG. 3 is a schematic perspective view of a driving system of the sheet punching device of the present invention.

FIG. 4 is a schematic side view showing a paper punching process in the paper punching device of the present invention and a meshing relationship of each gear of a drive system at that time.

[Explanation of symbols]

 2 Paper punching device 3 Inlet lower guide plate 4 Inlet upper guide plate 5 Pressing member 6 Branch claw 7 Lever 8 Inlet sensor 9 Conveyance roller 10 Paper punching device 11, 12 Rotary shaft 13 Punch 14 Dice 15 Scrap storage box 16 Punch scrap 19 Bin 20 Drive motor 21 drive gear 22 timing belt 23 driven gear 24 connecting gear 25 sector gear P copy paper

Continued on the front page (72) Inventor Mitsuru Ichikawa 2-28-24 Izumi 2-chome, Higashi-ku, Nagoya-shi, Aichi ・ Inside Ricoh Elemex Corporation (72) Inventor Yuji Ueno 2-28-24, Izumi 2-chome, Higashi-ku, Nagoya-shi, Aichi Ricoh Elemex Co., Ltd. (56) References JP-A-5-56397 (JP, U) JP-A-62-88599 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B26F 1/00-1/46

Claims (2)

(57) [Claims] 1. A sheet punching device for punching a sheet by inserting a tip end surface of a punch fixed to a rotating shaft into a hole of a die fixed to another rotating shaft. The rotating shafts of the dies are connected by gears of the same shape provided at each end,
A sector gear having the same tooth profile is fixed to one of the gears, and the tooth portion of the sector gear has the above-mentioned tooth at a fixed angle before and after the position where the tip end surface of the punch is inserted into the hole of the die. A sheet punching device provided at a position where it meshes with the other gear. 2. A sheet processing apparatus having a sheet conveying path, wherein the sheet punching apparatus according to claim 1 is arranged in said sheet conveying path, and performs a punching process without stopping the sheet being conveyed. Characteristic paper processing device.