JPH11262894A - Paper cutting device - Google Patents

Abstract

(57) [Problem] To provide a paper cutting device that can perform not only full cutting but also stable partial cutting with a constant uncut amount at all times under driving in only one direction that can reduce the load on a driving source. . SOLUTION: The cutting blade holder 28 is moved in accordance with the moving direction of the timing belt 34 on the side where the teeth of the toothless toothed gear 36, which is held in the middle of the upper and lower parallel timing belts 34, is held by the cutting blade holder 28. And the cutting blade holder 28 is fixed stoppers 39 and 40 or a movable stopper 41.
When the movement of the cutting blade 24 is restricted by the rotation of a predetermined value or more on the chipped tooth gear 36, the side where the teeth mesh with the timing belt 34 is switched up and down again to be in a fixed state and the moving direction of the cutting blade 24 is changed. Is switched. Therefore, if the movement of the cutting blade holder 28 is restricted between the fixed stopper 39 and the movable stopper 41, the paper 22 can be partially cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper cutting device applied to a receipt printer or the like.

[0002]

2. Description of the Related Art Generally, in printers and facsimile machines using long paper such as roll paper, a paper cutting device for cutting a printed paper into an appropriate length is transported to a printing section by a printed paper transporter. Many are provided at a position on the downstream side in the direction. In many cases, the paper cutting device in this case has a mechanism in which a linear plate-shaped movable blade and a fixed blade having a length over the entire width of the paper are combined, but recently, a disk-shaped cutting blade is moved in the width direction of the paper. A mechanism that cuts a sheet by moving the sheet to a small size has attracted attention because it can reduce the size and weight.

The function required in the case of the latter mechanism is to move a disk-shaped cutting blade (usually held by a cutting blade holder having a cover structure) in a direction crossing the printed paper. After the paper is cut, the paper is moved in the opposite direction to return to the standby position. For this reason, a configuration in which the cutting blade is necessarily reciprocated is included. The simplest configuration for this purpose is to switch the drive motor between normal rotation and reverse rotation. However, there are drawbacks in that the life of the drive motor is likely to be shortened and the control becomes complicated.

As an example of a configuration in which such a disadvantage is solved and the driving motor is always driven to rotate only in one direction to reciprocate the cutting blade (cutting blade holder), a boat-shaped slide provided on the cutting blade holder is provided. There is a drive cam system in which a spiral guide groove that a child follows is made endless at the upper end of the drive shaft and crosses back and forth. FIG. 6A shows an example of the configuration of a conventional paper cutting apparatus using the drive cam system. A drive cam 3 is provided between a pair of side plates 2 disposed near both ends in the width direction of a target paper 1. Is rotatably suspended. The drive cam 3 has a spiral guide groove 7 provided on a cutting blade holder 5 holding a disc-shaped cutting blade 4 and followed by a boat-shaped slider 6. It is formed so as to intersect, and is driven to rotate via a motor gear 10 and a drive gear 11 under driving by a drive motor 9. Accordingly, when the drive motor 9 rotates at the home position A of the cutting blade 4 and the drive shaft 8 rotates, the cutting blade holder 5 moves in the paper width direction due to the fitting relationship between the guide groove 7 and the slide 6. .
At this time, a rubber body 13 which is rotated by friction sliding on a plate-like fixed blade 12 having a length over the entire width of the paper 1 is attached on the axis of the cutting blade 4. As the cutting blade 4 rotates with the movement of the
The paper 1 is sequentially cut in cooperation with the paper 2. This allows
The paper 1 is cut (full cut). When the guide blade 7 moves to the other end shown at the position B and reaches the end of the guide groove 7, the guide groove 7 switches the moving direction of the cutting blade holder 5 to the opposite direction (return direction) toward the home position A side,
When it finally returns to the home position A, it stops and waits. Thus, according to the drive cam system, the cutting blade holder 5 can be reciprocated while the drive cam 3 is always rotated in one direction.

[0005] By the way, in consideration of application to a receipt printer or the like, there is a case where a partial cut is required in which a long sheet is not completely cut but has a remaining uncut length that is easily cut by hand. is there. For example, two copies of the same content are printed in succession, and the boundary is partially cut (the whole is full cut) to enable use as a stub, or half as the original receipt for customers, In some cases, half are issued as store receipts.

[0006]

However, in order to realize this partial cut by the drive cam system described above, for example, a structure as shown in FIG. 6A is used.
A drive motor 9 that can rotate forward and reverse is used.
Further, a sensor 14 for detecting that the cutting blade holder 5 has reached a partial cut position C set at a predetermined position in the middle of the moving range is added. As a result, the cutting blade holder 5 moves in the sheet width direction from the home position A with the forward rotation of the drive motor 9, and cuts the sheet 1 sequentially. Here, when the instruction is a partial cut instruction, FIG.
When the cutting blade holder 5 moves to the partial cutting position C and is detected by the sensor 14, the driving motor 9 is switched to the reverse rotation drive so that the cutting blade 4 does not perform full cutting of the paper 1 and returns to the home position. Return to A side. Thereafter, when there is a full cut instruction, the cutting blade 4 reciprocates between the home position A and the position B with the forward rotation of the drive motor 9 as described with reference to FIG.
Is fully cut and returns to the standby position.

As described above, even with the drive cam system,
The partial cut can be realized by using the method of driving the drive motor 9 in the normal direction and the reverse direction, but it is originally a mechanism for rotating the motor only in one direction.
The initial problem that the life of the motor is likely to be shortened by reversing the motor remains.
In addition, it is affected by the detection error of the sensor 14, the error of the reverse rotation position of the drive motor 9, and the like, and it is also difficult to realize a desired uniform uncut amount in the partial cut.

According to Japanese Patent Application Laid-Open No. Hei 10-29193, a timing belt having two pulleys, a toothed shape formed on the inner peripheral surface thereof, and a timing belt held by a cutting blade holder are arranged between the upper and lower parallel timing belts. A configuration has been proposed in which a sheet is cut (full cut) by driving a drive motor (timing belt) in only one direction using a predetermined missing tooth gear and a stopper, and the sheet is returned to a home position. However, there is no mention of a cutting form such as a partial cut.

In view of this, the present invention provides not only full cutting but also driving in only one direction which can reduce the load on the driving source.
It is an object of the present invention to provide a paper cutting device in which the uncut amount is always constant and stable partial cutting can be performed.

[0010]

According to the first aspect of the present invention,
In a paper cutting device that cuts a sheet by moving a cutting blade in the width direction of the sheet, two pulleys rotatably disposed at a position in a width direction of a target sheet and a tooth shape are formed on an inner peripheral surface. A timing belt that is wound between these pulleys and is driven to rotate in one direction with the rotation of the pulley; a cutting blade holder movably provided along the timing belt and holding the cutting blade; The timing belt on the lower side is meshed with the lower timing belt when the missing tooth portion is located at the middle of the upper and lower parallel timing belts held by the cutting blade holder and the timing is on the upper side when the missing tooth portion is facing downward. The belt and the teeth mesh with each other, and the fixed state is released at the position where the missing tooth part is directed upward and downward, and the fixed state is released when a rotational force of a predetermined value or more acts. And toothless gear rotated by, and two fixing stopper limiting the movement of the cutting blade holder at a predetermined position parallel to the region of the upper and lower of the timing belt,
A movable stopper movably provided at a predetermined position near one end of the timing belt within a movement range of the cutting blade holder limited by these fixed stoppers so as to be able to advance and retreat at a position for restricting the movement of the cutting blade holder; A movable stopper drive mechanism for selectively moving the stopper forward and backward, the cutting blade holder moves together with the timing belt in accordance with the moving direction of the timing belt on the side where the teeth of the missing tooth gear mesh, and the cutting blade holder is fixed stopper or When the movement is restricted by contacting the movable stopper, a rotational force of a predetermined value or more acts on the missing tooth gear, and the side where the teeth mesh with the timing belt is switched up and down to be again in a fixed state and the moving direction of the cutting blade is switched. I was able to.

Accordingly, the timing belt stretched between the two pulleys is always driven to rotate in a fixed direction, but the moving direction is opposite between the upper part and the lower part. When the missing tooth portion is directed upward, the lower toothed belt meshes with the lower timing belt, and the toothless tooth gear located in the middle of these upper and lower parallel timing belts engages with the cutting blade holder in accordance with the moving direction of the lower timing belt. When the missing tooth portion is directed downward, the upper timing belt meshes with the teeth, and the cutting blade holder also moves according to the moving direction of the upper timing belt. Thereby, the reciprocating movement of the cutting blade holder holding the cutting blade is basically performed. Here, the switching of the moving direction is performed while the one-way drive of the timing belt is maintained, and the movement of the cutting blade holder is stopped by a fixed stopper or This is performed by mechanically restricting the movable stopper to apply a rotational force equal to or more than a predetermined value to the chipped gear. Therefore, if the movement of the cutting blade holder is restricted between the pair of fixed stoppers, it is possible to perform the full cutting operation of the paper. In addition, if the movement of the cutting blade holder is restricted between the fixed stopper and the movable stopper, the partial cutting operation of the paper can be performed. However, in the partial cut, the cutting is always performed to the position mechanically restricted by the movable stopper. Therefore, the uncut amount is constant and a stable partial cut is achieved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. The paper cutting device according to the present embodiment is applied to, for example, a receipt paper cutting device 20 in a receipt printer built in a POS terminal.

The receipt paper cutting device 20 according to the present embodiment.
As shown in FIG. 5, is disposed downstream of the printing unit 21 of the receipt printer in the transport direction of the receipt paper (paper) 22, and is basically at least the full width of the target receipt paper 22. Fixed blade 2 having a length of
A method of cutting the receipt paper 22 in cooperation with the fixed blade 23 and the cutting blade 24 by moving the disk-shaped cutting blade 24 while rotating along the front end of the sheet 3 is used. Here, the fixed blade 23 is integrated with a cutter frame 25 fixed at a predetermined position in the printer housing.
A rubber member 26 is mounted on the axis of the cutting blade 24 so as to rotate by frictionally sliding on the fixed blade 23 and also rotate the cutting blade 24 integrally. Such a cutting blade 24 is rotatably held by a cutting blade holder 28 provided with a protective cover 27 for preventing the blade from being exposed.

2 is located near both ends of the cutter frame 25.
Pulleys 29 and 30 are rotatably mounted.
Here, the pulley 29 located on the home position A side
Is a drive pulley that is driven to rotate only in one direction (counterclockwise in FIG. 1) via a drive motor 31, a motor gear 32, and a drive gear 33. These pair of pulleys 2
A timing belt 34 is stretched between 9 and 30. Therefore, in the timing belt 34 driven only in one direction, with respect to the upper and lower parallel portions, the lower portion 34d always moves in the cutting direction away from the home position A, and the upper portion 34u always faces the home position A side. It will move in the return direction.

Further, on the inner peripheral surface side of the timing belt 34, a tooth profile 34a is formed over the entire circumference as shown in FIG. Further, the cutting blade holder 28 is slidable in the paper width direction along a guide 35 formed in a part of the cutter frame 25 in parallel with the timing belt 34. A toothless gear 36 is rotatably mounted on the cutting blade holder 28. The rotation axis of the toothless gear 36 is always located between the parallel upper part 34u and the lower part 34d of the timing belt 34, and is fixed at a position where the toothless part 36b faces upward and downward, When a rotational force equal to or more than a predetermined value is applied, the fixed state is released and the motor can rotate. Specifically, on the axis of the notched gear 36, a notch 37 whose two opposing sides are cut in an arc shape is provided.
The control shaft 37 having a is fixed. Further, two leaf springs 38 fixed to the cutting blade holder 28 and holding the control shaft 37 are provided. Thus, when these leaf springs 38 are in a state of sandwiching the pair of notches 37a, the toothless gear 36 is fixed by the urging force of the leaf springs 38, and when a rotational force equal to or more than a predetermined value is applied, these chipped gears 36 are turned off. The leaf spring 38 is deformed in the expanding direction to release the fixed state, and the toothless gear 36 can rotate.

Next, the meshing relationship between the teeth 36a of the toothless gear 36 and the tooth profile 34a of the timing belt 34 will be described with reference to FIG. Teeth 36a of missing tooth gear 36
Is set so as to mesh with the tooth profile 34a of the upper portion 34u of the timing belt 34 when the missing tooth portion 36b faces downward, and to engage with the tooth profile 34a of the lower portion 34d of the timing belt 34 when the missing tooth portion 36b faces upward. Have been. Thus, when the teeth 36a are engaged with the tooth profile 34a of the lower portion 34d of the timing belt 34, the cutting blade holder 28 moves in the cutting direction, and the teeth 36a are engaged with the tooth profile 34a of the upper portion 34u of the timing belt 34. At times, the cutting blade holder 28 moves in the return direction.

Also, a part of the cutter frame 25 is used to fix mechanically restricting the movement of the cutting blade holder 28 at an inner position (in an upper and lower parallel region) near both ends of the timing belt 34. Stoppers 39 and 40 are formed. The fixed stopper 39 is set at a position corresponding to the home position A of the cutting blade 24 (cutting blade holder 28), and the fixed stopper 40 is set at a position B exceeding at least the full cut position of the receipt paper 22. Of course, when the cutting teeth 24 are located at any of the positions A and B, the paper cutting device does not prevent the receipt paper 22 from being transported.

Further, these fixed stoppers 39, 40
The cutting blade holder 28 is located within a moving range of the cutting blade holder 28 limited by
Movable stopper 41 for selectively and mechanically restricting the movement of
Is provided. The movable stopper 41 is used for a partial cut, and is rotatable about a fulcrum 42 so as to advance and retreat in a movement locus of the cutting blade holder 28 at a partial cut position C set with reference to the home position A. Is provided. The movable stopper 4 is provided on a frame 43 fixed to the receipt printer housing.
A spring 4 which is locked between a part of the cutting blade holder 1 and biases the movable stopper 41 in a retracting direction which does not interfere with the cutting blade holder 28.
4 and a solenoid 45 that is energized at the time of partial cutting and displaces the movable stopper 41 to an advanced position where the movable stopper 41 can interfere with the cutting blade holder 28.
Is provided.

In such a configuration, first, the operation at the time of full cutting of the receipt paper 22 will be described. in this case,
The solenoid 45 is not energized, and the movable stopper 41 is retracted to a position where the movable stopper 41 does not interfere with the cutting blade holder 28 by the urging force of the spring 44. Further, the cutting blade holder 28 is stopped and
In the standby state, it is located at the home position A as shown in FIG. At this time, the missing tooth portion 36b of the missing tooth gear 36
Are fixed upward, and the teeth 36a are in mesh with the teeth 34a of the lower portion 34d of the timing belt 34 (see FIG. 4). Accordingly, when a paper cut command is issued and the drive pulley 29 is rotated counterclockwise by the drive motor 31, the lower portion 3 of the timing belt 34 is rotated.
Since 4d moves in the cutting direction, the cutting blade holder 28 also moves in the cutting direction. Accordingly, the cutting blade 24 is moved to the fixed blade 2
3 and starts cutting the receipt paper 22.

When the cutting blade holder 28 moves in the cutting direction and moves to the position B where it comes into contact with the fixed stopper 40 as shown in FIG. 2, the receipt paper 22 is fully cut. At this time, the cutting blade holder 28 cannot move any more in the cutting direction due to the fixed stopper 40, and thus stops at the position where it comes into contact with the fixed stopper 40. However, since the timing belt 34 continues to rotate, referring to FIG. 4, the tooth gear 36a whose tooth form 34a is meshed with the tooth 36a has a large rotational force equal to or greater than a predetermined value to rotate in the counterclockwise direction. Works. This rotational force overcomes the elastic force of the leaf spring 38 and the leaf spring 3
Since the fixed state of the missing tooth gear 36 is released at the same time as the 8 is expanded and deformed, the missing tooth gear 36 also rotates counterclockwise according to the timing belt 34. The missing tooth gear 36 is 18
When rotated by 0 °, the leaf spring 38 is moved to the notch 37 of the control shaft 37.
a is fixed. Then, the missing tooth gear 36 is now in a state in which the missing tooth portion 36b is fixed downward, and the teeth 36a are connected to the upper portion 34 of the timing belt 34.
The tooth shape 34a of u is engaged with the tooth shape 34a. Therefore, as the timing belt 34 continues to rotate counterclockwise, the cutting blade holder 28 moves in the return direction according to the upper portion 34u.

Thereafter, when the cutting blade holder 28 returns to the position where it comes into contact with the fixed stopper 39, the cutting blade holder 28
Cannot be moved any more in the return direction by the fixed stopper 39, and therefore stops at the position where it comes into contact with the fixed stopper 39. However, since the timing belt 34 keeps rotating, a large rotational force equal to or more than a predetermined value which is intended to rotate in the counterclockwise direction acts on the missing tooth gear 36 in which the tooth 36a is meshed with the tooth profile 34a. Since the rotational force overcomes the elastic force of the leaf spring 38 to expand and deform the leaf spring 38 and release the fixed state of the missing tooth gear 36, the missing tooth gear 36 also rotates according to the timing belt 34. When the notched gear 36 rotates by 180 °, the leaf spring 38 enters a fixed state in which the notch 37a of the control shaft 37 is clamped. Then, the missing tooth gear 36 is now replaced with the missing tooth portion 36.
b is fixed upward, and the teeth 36a mesh with the teeth 34a of the lower portion 34d of the timing belt 34. That is, the process returns to the standby state shown in FIG.
At this time, the drive of the drive motor 31 is stopped at a predetermined timing based on a home position sensor (not shown),
Wait for the next cut command.

Next, the operation when the receipt paper 22 is partially cut will be described. In this case, the solenoid 45 is energized, and the movable stopper 41 is moved to the spring 44 as shown in FIG.
At the partial cut position C against the urging force of the cutting blade holder 28. Further, in the stop / standby state, the cutting blade holder 28 is located at the home position A as shown in FIG. 1 as in the case of the full cut, and when the paper cut command is issued, the drive pulley 29 is turned counterclockwise by the drive motor 31. When rotated, the lower portion 34d of the timing belt 34 moves in the cutting direction, so that the cutting blade holder 28 also moves in the cutting direction. Accordingly, the cutting blade 24 starts cutting the receipt paper 22 in cooperation with the fixed blade 23.

When the movement of the cutting blade holder 28 in the cutting direction advances and moves to the partial cut position C where it contacts the movable stopper 41 as shown in FIG.
Since the movable stopper 41 cannot be moved any more in the cutting direction by the movable stopper 41, the stopper 8 stops at a position in contact with the movable stopper 41. Therefore, the cutting of the receipt paper 22 does not proceed any more, and it is not in full cut but in a partial cut state. At this time, the cutting amount, that is, the uncut amount of the receipt paper 22 is at a position where the cutting blade holder 28 is mechanically limited by the movable stopper 41.
Always the same amount. Further, since the timing belt 34 continues to rotate, the toothed gear 36 whose tooth shape 34a is meshed with the tooth shape 34a tries to rotate in the counterclockwise direction according to the same principle as that at the time of full cutting described with reference to FIG. A large rotational force equal to or greater than a predetermined value acts. This rotational force overcomes the elastic force of the leaf spring 38 to expand and deform the leaf spring 38 and at the same time releases the fixed state of the missing tooth gear 36, so that the missing tooth gear 36 also rotates counterclockwise according to the timing belt 34. . When the notched gear 36 rotates by 180 °, the leaf spring 38 enters a fixed state in which the notch 37a of the control shaft 37 is clamped. Then, the missing tooth gear 36 is now in a state where the missing tooth portion 36b is fixed downward, and the tooth 3
6a is the tooth shape 3 of the upper portion 34u of the timing belt 34
4a. Therefore, as the timing belt 34 continues to rotate counterclockwise, the cutting blade holder 28 moves in the return direction according to the upper portion 34u.

Thereafter, when the cutting blade holder 28 returns to the position where it comes into contact with the fixed stopper 39, the cutting blade holder 28 cannot be moved further in the returning direction by the fixed stopper 39 as in the case of full cutting. Although it stops at the position where it abuts on 39, the timing belt 34 keeps rotating and moving, so that a large rotational force of a predetermined value or more that is going to rotate in the counterclockwise direction acts on the missing tooth gear 36, and the fixed state thereof is changed. Since it is released, the chipped tooth gear 36 also rotates counterclockwise according to the timing belt 34,
When the plate spring 38 rotates by 180 °, the leaf spring 38 enters a fixed state in which the notch 37a of the control shaft 37 is clamped. As a result, the missing tooth gear 36 is now in a state in which the missing tooth portion 36b is fixed upward, and the teeth 36a mesh with the tooth profile 34a of the lower portion 34d of the timing belt 34. That is, the process returns to the standby state shown in FIG. At this time, the drive of the drive motor 31 is stopped at a predetermined timing based on a home position sensor (not shown), and waits for the next cut command.

As described above, according to the present embodiment, the cutting blade holder 2 is held between the pair of fixed stoppers 39 and 40 while the timing belt 34 is always driven to rotate in one direction.
If the movement of the receipt paper 8 is restricted, the full cut operation of the receipt paper 22 can be performed. If the movement of the cutting blade holder 28 is restricted between the fixed stopper 39 and the movable stopper 41 while the timing belt 34 is always driven to rotate in one direction, the partial cut operation of the receipt paper 22 can be performed. However, at the time of the partial cut, the cut is always made up to the position mechanically restricted by the movable stopper 41. Therefore, only by appropriately setting the position of the movable stopper 41, the uncut amount is constant and the stable partial cut operation is performed. be able to.

In this embodiment, an example is given in which the cutting is performed by the cooperation of the disk-shaped cutting blade 24 and the plate-shaped fixed blade 23. However, the present invention is not limited to such a method. The same method can be applied to a method in which cutting is performed in cooperation with disk-shaped cutting blades that move along the guide plate.

The present invention is not limited to the application to a receipt printer, but may be applied to any device that requires a partial cut and a full cut for long paper.

[0028]

According to the present invention, the cutting blade holder is held by the cutting blade holder in accordance with the moving direction of the timing belt on the side where the teeth of the chipped tooth gear located in the middle of the upper and lower parallel timing belts mesh. When the cutting blade holder moves with the timing belt and abuts on the fixed stopper or the movable stopper to limit the movement, a rotational force of a predetermined value or more acts on the missing tooth gear, and the side where the teeth mesh with the timing belt is switched up and down. The timing blade is switched to the fixed state, and the direction of movement of the cutting blade is changed. If the movement of the holder is restricted, the full cutting operation of the paper can be performed, and the movement of the cutting blade holder between the fixed stopper and the movable stopper By restricting the paper, a partial cut operation of the paper can be performed, and at the time of the partial cut, the cut is always made up to the position mechanically restricted by the movable stopper. By only setting appropriately, it is possible to perform a stable partial cut with a constant uncut amount.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a case where a cutting blade holder according to an embodiment of the present invention is located at a home position.

FIG. 2 is a schematic side view showing a case where a cutting blade holder is located at a full cutting position.

FIG. 3 is a schematic side view showing a case where a cutting blade holder is located at a partial cutting position.

FIG. 4 is an enlarged side view showing the operation principle of the vicinity of the timing belt and the missing tooth gear;

FIG. 5 is a perspective view showing a configuration of a receipt paper cutting device.

FIG. 6 is a schematic side view showing a conventional example of a drive cam system.

[Explanation of symbols]

 Reference Signs List 22 paper 24 cutting blade 28 cutting blade holder 29, 30 pulley 34 timing belt 34a tooth profile 34u upper portion 34d lower portion 36 chipped gear 36a chipped tooth portion 36b tooth 39, 40 fixed stopper 41 movable stopper 41 movable stopper drive mechanism

Claims (1)

[Claims] 1. A sheet cutting device for cutting a sheet by moving a cutting blade in a sheet width direction, comprising: two pulleys rotatably disposed at a position in a sheet width direction of a target sheet; A timing belt having a tooth profile formed on a surface thereof, being wound between these pulleys, and being driven to rotate in one direction with the rotation of the pulleys; and a cutting belt movably provided along the timing belt and holding the cutting blade. A blade holder, which is held by the cutting blade holder and is located in the middle of the upper and lower parallel timing belts, and when the missing tooth portion is upward, the lower timing belt and the teeth mesh with each other so that the missing tooth portion faces downward. Sometimes when the upper timing belt meshes with the teeth and the missing tooth portion is fixed at a position where the missing tooth portion is directed upward and downward, and a rotational force of a predetermined value or more is applied. A toothless gear that is released when the fixed state is released, two fixed stoppers that limit the movement of the cutting blade holder at predetermined positions in the upper and lower parallel regions of the timing belt, and are limited by these fixed stoppers. A movable stopper movably provided at a predetermined position within the movement range of the cutting blade holder to restrict the movement of the cutting blade holder, and a movable stopper drive mechanism for selectively moving the movable stopper forward and backward. The cutting blade holder moves together with the timing belt in accordance with the moving direction of the timing belt on the side where the teeth of the missing tooth gear mesh with the timing belt, and the cutting blade holder abuts on the fixed stopper or the movable stopper to limit the movement of the missing tooth. A rotational force greater than or equal to a predetermined value acts on the gear, and the side where the teeth mesh with the timing belt is switched up and down to be again in a fixed state. Paper cutting apparatus, wherein the moving direction of the cutting blade is switched.