KR20090102674A - Cloth cutting device of sewing machine for button hole stitch - Google Patents

Abstract

PURPOSE: A cloth cutting device of a sewing machine for buttonhole stitch is provided to restrict a driving period at low speed remarkably when an interval between a cutter and a cutter support is widened. CONSTITUTION: A cloth cutting device of a sewing machine for buttonhole stitch includes a cutter, a cutter support, a moving unit, a driving shaft, a pulse motor, a rotation quantity detection part(55), and a control part(50). The cutter has a point of a knife. The cutter support is arranged on an opposite side of the cutter. The cutter support cuts the fiber with the point of the knife. The moving unit moves the cutter or the cutter support. The driving shaft is supported by a sewing machine frame pivotally. The pulse motor is connected to the driving shaft. The rotation quantity detection part detects the rotation quantity of the pulse motor. The control part controls the pulse motor based on the detection results of the rotation quantity detection part. The control part performs a detection mode and a fiber cutting mode.

Description

Cloth cutting device of buttonhole sewing machine {CLOTH CUTTING DEVICE OF SEWING MACHINE FOR BUTTON HOLE STITCH}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cloth cutting device for a buttonhole sewing machine that forms holes such as buttonholes in a to-be-sealed material such as cloth.

In general, a button hole (hereinafter referred to as an 'eyelet') consisting of a round hole portion, which is a droplet-shaped hole, and a straight straight hole (cutting) continuous to the cloth to be sewn, is formed. A buttonhole sewing machine is known which automatically executes a series of cuttings to form needle stitches around the eyelets.

The buttonhole sewing machine has one of the scalpels and the scalpel up and down in a state in which a cloth is disposed between a scalpel having a knife tip having a shape corresponding to the shape of the eyelet and a scalpel portion arranged to face the scalpel. It is provided with the cloth cutting device which joins both sides by moving and forms the eyelet in a cloth.

In a buttonhole sewing machine equipped with such a cloth cutting device, an eyelet is formed by a cloth cutting tool with respect to a cloth fixedly set on a feeder, and then a feeder (cloth) moves along the periphery of the eyelet of the cloth. The needle stitch forming mechanism, such as a needle, is moved while moving (). In addition, depending on the type of fabric, after cutting along the periphery of the eyelet to be formed, the cloth cutting device may be driven to form the eyelet.

For example, as described in Patent Literature 1, a sewing machine using a pulse motor is known as a driving source for moving a scalpel to join a scalpel part. The rotational motion of the pulse motor is transmitted to the scalpel through a link mechanism or the like and descends toward the scalpel receiver, and the knife tip of the scalpel is fitted to the scalpel receiver to form eyelets on the fabric.

Then, the pulse motor is controlled to lower the scalpel at high speed from the origin position where the scalpel is rising to just before the mating position with the scalpel receiving portion, and then to decelerate at a low speed to lower the mating position and press the scalpel to cut the cloth. Doing. After cutting, the scalpel is raised at a high speed to return to the home position.

Specifically, this will be described with reference to FIG. 11. When the cloth cutting start timing T101 is reached, the pulse motor is accelerated to a high speed (for example, 4000pps), and then decelerated to a low speed (for example, 1000pps) after maintaining the speed for a predetermined time. Here, the deceleration completion timing T102 is set before the matching timing T103 (for example, 1000 pulse points). Then, the pulse motor is driven at a low speed until the mass moves to the matching timing T103. After the scalpel reaches the matching timing T103, the pulse motor is driven at low speed as it is, and by this driving, the cloth is cut by generating an pressing force on the fabric sandwiched between the scalpel and the scalpel receiving portion. Thereafter, once the pulse motor is stopped (stop point T104), the pulse motor is then driven in reverse rotation at high speed to return the scalpel to the home position. This return point is the cloth cutting completion timing T105.

Here, the number of pulses from the deceleration completion timing T102 to the stop position T104 is stored in a plurality of data as different pulse numbers, and is based on the type of the scalpel part when cutting the cloth, the material of the cloth, and the thickness. The data of the corresponding pulse number can be selected.

[Patent Document 1] Japanese Patent Laid-Open No. 2001-334088

As the cutting is repeated, the cutting edge of the scalpel always comes into contact with the same portion of the scalpel part, whereby the contact portion of the scalpel part wears and a scalpel is formed, thereby reducing the degree of cutting. For this reason, the surface of the scalpel receiving part is polished and flattened to remove scalpel marks. However, if the surface of the scalpel receiving part is wiped, the surface position of the scalpel receiving part becomes downward, so that the gap with the scalpel becomes wider, and the matching position with the scalpel changes, so that a sufficient cutting force cannot be obtained.

For this reason, even if the matching position T103 retreats as shown in Fig. 12, in order to generate sufficient pressing force, the number of pulses for the pulse motor from the deceleration completion position T102 to the stop position T104 increases. You need to reset it. Increasing the number of pulses between these positions, however, resulted in a prolonged operating period at low speed, thereby prolonging the cycle time.

An object of the present invention is to reduce the operation time at low speed and to shorten the cycle time when the distance between the scalpel and the female receiving part is widened.

The cloth cutting device of the buttonhole sewing machine according to the invention of claim 1,

A scalpel having a knife tip, a scalpel receiving part arranged to face the scalpel and cooperating with the knife tip of the scalpel, and a moving mechanism connected to one of the scalpel or the scalpel part to move and move; A drive shaft connected to the moving mechanism, a pulse motor connected to the drive shaft, supported by a sewing machine frame to move and contact one of the scalpel and the female receiving part to the other by rotation, a pulse motor connected to the drive shaft, and an amount of rotation of the pulse motor And a control unit for controlling the pulse motor based on a detection result of the rotation amount detection unit and a detection result of the rotation amount detection unit.

The control unit rotates the pulse motor at a predetermined speed from an origin position when approaching the scalpel and the female receiving unit, and when a deviation occurs between a detection result from the rotation amount detecting unit and an input pulse of the pulse motor, When the pulse motor is stopped and the detection mode for storing the detection result from the rotation amount detection unit at the stop as the number of coincidence pulses, and the approach result of the scalpel and the mass receiving unit are approached, the detection result from the rotation amount detection unit A cloth cutting mode is executed in which the pulse motor is rotated at high speed until the number of coincidence pulses is reached, and the pulse motor is rotated at low speed until the detection result from the rotation amount detection unit exceeds a predetermined number of pulses at the matched pulse number. It is characterized by being able.

Invention of Claim 2 is a cloth cutting device of the buttonhole sewing machine of Claim 1,

The control unit, while counting the number of pulses of the pulse motor when the detection mode is executed, the control unit is faster than the predetermined speed of the detection mode until the count value is the number of non-contact pulses that do not contact the scalpel and the female receiving portion; And rotate the pulse motor at a predetermined speed in the detection mode when the count value is a non-contact pulse number, thereby driving the drive shaft and the moving mechanism to bring the scalpel and the scalpel part closer, When a deviation occurs in the detection result from the rotation amount detector, the pulse motor is stopped and the count value at the time of stopping is stored as the number of coincidence pulses.

Invention of Claim 3 is a cloth cutting device of the buttonhole sewing machine of Claim 1 or 2,

The predetermined speed of the detection mode and the second set speed of the cloth cutting mode coincide, and the first set speed of the cloth cutting mode and the third set speed of the detection mode coincide.

According to the present invention, when the cloth cutting mode is executed, the pulse motor rotates at high speed up to the number of coincidence pulses detected by the detection mode, so that the operating section at high speed can be made very wide. If the detection mode is executed after the scalpel receiving section is wiped, even if the distance between the scalpel and the scalpel widens due to maintenance, the operation period at low speed can be greatly suppressed and the cycle time can be shortened.

1 is a side view showing a schematic configuration of a sewing machine according to the present embodiment.

2 is a perspective view showing a schematic configuration of a cloth cutting device according to the present embodiment.

3 is an explanatory view showing the shape and engagement relationship between the blade end of the scalpel and the scalpel receiving portion of the cloth cutting device of FIG. 2, (a) is a scalpel portion of S size, and (b) is a scalpel of M size The receiving part and (c) show the female receiving part of L size.

4 is a block diagram showing the main control configuration of the sewing machine of FIG.

5 is an explanatory diagram showing an A-phase output signal and a B-phase output signal of the encoder of FIG. 4.

FIG. 6 is a diagram illustrating a relationship between an amount of deviation of an encoder and a torque of a pulse motor when the pulse motor is driven when the scalpel and the female receiving part of FIG. 3 contact each other.

FIG. 7 is a flowchart showing a flow of a detection mode executed in the cloth cutting device of FIG. 2.

FIG. 8 is a diagram showing the rotational speed of the pulse motor, the number of pulses, and the amount of deviation of the encoder when the detection mode of FIG. 7 is executed.

FIG. 9 is a flowchart showing the flow of the cloth cutting mode executed in the cloth cutting device of FIG. 2.

FIG. 10 is a diagram showing the rotational speed of the pulse motor, the number of pulses, and the amount of deviation of the encoder when the cloth cutting mode of FIG. 9 is executed.

11 is a diagram showing the rotational speed and the number of pulses when cutting a cloth of a pulse motor provided in a conventional cloth cutting device.

12 is a diagram showing the rotational speed and the number of pulses at the time of cutting the cloth after the initial state and maintenance of the pulse motor provided in the conventional cloth cutting device.

Explanation of symbols on the main parts of the drawings

1: sewing machine 30: cloth cutting device

31: scalpel receiving unit 32: scalpel

33: drive shaft 34: pulse motor

34b: pulse motor driving circuit 35: moving mechanism

36: motor gear 37: ball screw member

38: gear 39: housing

40: link mechanism 41: link

42: lever 44: linear motion gear

45: linear shaft 45a: rack portion

50: control unit 55: encoder (rotation amount detection unit)

55b: encoder circuit 57: operation panel

EMBODIMENT OF THE INVENTION Hereinafter, the cloth cutting device which is an example of embodiment of this invention is demonstrated with reference to drawings.

As shown in Fig. 1, the sewing machine 1 equipped with the above-described cloth cutting device 30 (shown in Fig. 2) is provided with a basic configuration as a sewing machine for performing eyelet buttonhole stitches. The sewing machine 1 is provided with a bed portion 2 forming a substantially rectangular box shape, a vertical body portion 3 provided at the rear of the bed portion 2, and extending forward from an upper portion of the vertical body portion 3. The sewing machine frame 5 with the arm part 4 and the sewing machine table on which the sewing machine frame 5 is mounted are provided.

And the needle bar 10 provided with the sewing needle 6 in the lower end so that it may extend below is provided at the front-end | tip part of the arm part 4 so that the oscillation movement with respect to the east and right and left and right sides is possible. In addition, the bed portion 2 is provided with a looper base having a looper portion 11a having a looper (not shown) and a spreader (not shown) to assist the looper, facing the needle bar 10. (11) is provided. In the sewing machine frame 5, each drive mechanism (not shown) for moving the needle bar 10 vertically and horizontally and driving the looper and the spreader in synchronism with this is provided.

In addition, the upper surface of the bed portion 2 is provided with a feed table 18 (shown in cross section in FIG. 1) in which the cloth is set, and a pair of cloth pressers for pressing the cloth on the upper surface portion of the feed table 18. (19) is provided. The conveyance table 18 is formed in a thin rectangular box shape having an open lower surface as a whole, and is formed between the pair of cloth presses 19 and has an opening in the front and rear directions on the upper surface thereof. . In addition, the transfer table 18 is horizontally moved by a transfer mechanism (not shown) installed in the bed portion 2.

In addition, the sewing machine 1 is provided with a cloth cutting device 30 for forming an eyelet on the cloth. The cloth cutting device 30 will be described later. In the sewing machine 1, the cloth cutting device 30 forms eyelets on the fabric, and at the same time, the looper is driven in accordance with the movement of the needle bar 10 and the vibration of the needle, and the sewing needle 6 and the looper; Collaboration of the eyelets is intended to carry out surrounding the eyelets.

Next, the cloth cutting device 30 will be described. As shown in FIG. 2, the cloth cutting device 30 is mainly arranged opposite to the scalpel receiver 31 and the scalpel receiver 31 corresponding to the shape of the eyelet, and at the upper end thereof, a scalpel 32 having a knife tip formed thereon. ), A drive shaft 33 rotatably supported by the sewing machine frame 5, a pulse motor 34 for rotationally driving the drive shaft 33, and a scalpel receiver 31 by a rotational movement of the drive shaft 33. ) Is configured to include a shanghai copper mechanism (35) for contacting and spaced apart relative to the scalpel (32). In addition, in FIG. 2, the main component part of the sewing machine 1 is abbreviate | omitted in order to simplify drawing.

The pulse motor 34 fixed in the bed portion 2 on the side of the longitudinal body portion 3 is, for example, one having a resolution of 400 divided. The output shaft of the pulse motor 34 is arrange | positioned along the up-down direction, and the motor gear 36 is fixed to the front-end | tip. The pulse motor 34 is provided with an encoder 55 (see Fig. 4) as a rotation amount detecting unit, for example, an encoder 55 having a resolution of 400 divided by the rotation motor for detecting the rotation amount of the pulse motor 34.

In the vertical body portion 3, the ball screw member 37 extending up and down is rotatable about its axis by a bearing (not shown) fixed to the bed portion 2 or the arm portion 4. Is supported.

The gear 38 meshed with the motor gear 36 is fixed to the lower end of the ball screw member 37. Therefore, the ball screw member 37 is rotated by the rotational drive of the pulse motor 34.

A housing 39 is disposed in the vertical body portion 3, and a nut (not shown) engaged with the ball screw member 37 is installed in the housing 39, and the ball screw member 37 is provided. The housing 39 moves up and down by the rotation of. Moreover, in order to suppress rotation of the housing 39, the shaft (not shown) extended up and down is slidably penetrated by the housing 39, and is supported by the apparatus frame.

In addition, the housing 39 is provided with a link mechanism 40 constituted by a pair of links 41 and 41 and a lever 42. The lower ends of the pair of links 41 and 41 are rotatably supported on both sides of the housing 39, and the upper ends of the pairs of links 41 and 41 are rotatably supported by the two-pronged ends of the levers 42 having a substantially Y-shape. The rotation of the links 41, 41 and the lever 42 is around the axis of rotation along the extending direction of the arm part 4.

And the drive shaft 33 extended in the extension direction of the arm part 4 is provided in the arm part 4 so that it may rotate around the rotating shaft of an extension direction. The base end of the lever 42 is fixed to an end portion of the drive shaft 33 on the longitudinal body portion 3 side. Therefore, when the pulse motor 34 rotates, the housing 39 is moved by the rotation of the ball screw member 37, and the drive shaft 33 is rotated through the link mechanism 40.

The shank moving mechanism 35 which is a pinion rack mechanism is comprised with the linear motion gear 44 fixed to the other end of the drive shaft 33, and the linear motion shaft 45 which meshes with the linear motion gear 44. As shown in FIG. The linear shaft 45 extends in the vertical direction and is supported by the arm portion 4 so as to be movable. And the rack part 45a is formed in the outer periphery of the linear motion shaft 45, and the linear motion gear 44 meshes with the said rack part 45a.

That is, the linear motion gear 44 rotates together with the drive shaft 33, so that the linear motion shaft 45 moves in and out of motion.

And the linear motion shaft 45 is attached so that a lower end may protrude below an arm and the scalpel receiving part 31 can be replaced. The scalpel 32 is detachably attached to the bed portion 2 so as to face the scalpel receiving portion 31. As shown in Fig. 3, the blade end of the scalpel 32 has one end portion 32a formed in a ring shape and the other end portion 32b formed in a linear shape.

On the other hand, the lower surface of the scalpel receiving portion 31, which is the engaging portion of the scalpel 32 with the cutting edge, is formed in a shape in which one end portion 32a of the scalpel 32 and a part of the other end portion 32b can abut. It is. Here, the scalpel receiving part 31 is S size, M size, L size different in contact length with the other end portion 32b of the scalpel 32, as shown in (a) to (c) of FIG. Since it is used, the scalpel receiving part 31 of the size according to the thread cutting length is attached to the bed part 2.

With this configuration, when the pulse motor 34 is driven to rotate in the forward rotation direction, the mass receiving part 31 is lowered, and when the motor is driven to rotate in the half rotation direction, the mass receiving part 31 is raised.

When the pulse motor 34 rotates forward, the scalpel receiving portion 31 coincides with the cutting edge of the scalpel 32, and the scalpel receiving portion 31 further presses the cutting edge of the scalpel 32. Thus, the transition scalpel 32 and the scalpel 31 are pressed down completely. Then, when the eyelet is formed on the cloth, the pulse motor 34 is driven to rotate in the direction of half rotation, so that the scalpel receiver 31 is raised. When the home position sensor (not shown) turns ON, the scalpel receiving unit 31 which is continuously raised stops at the home position which is the re-raising position of the mass receiving unit 31.

As shown in FIG. 4, the sewing machine 1 is provided with a control unit 50 for controlling the operation of the cloth cutting device 30 together with the operation of the sewing machine 1. The control unit 50 includes a main shaft motor driving circuit 51b for driving the main shaft motor 51a of the sewing machine, an X-axis motor driving circuit 52b for driving the X-axis motor 52a provided in the transfer mechanism, and , The Y-axis motor drive circuit 53b for driving the Y-axis motor 53a provided in the transfer mechanism, and the swing motor 54a for turning the needle bar 10 and the looper portion 11a. A drive circuit 54b, a pulse motor drive circuit 34b for driving the pulse motor 34, an encoder circuit 55b for counting the count value of the encoder (rotation amount detector) 55, and various operation instructions The operation panel 57 to which is input is electrically connected via the I / F 56, respectively.

The control unit 50 will be described later on the basis of the ROM 50a in which data used in various control programs and programs are stored, data read from the ROM 50a, data input or set from the operation panel 57, and a program. RAM 50b and EEPROM 50d in which data calculated by the CPU 50c and the like are stored, and a CPU 50c which performs various processes based on the program.

Here, the control program includes a sewing program for executing sewing, a cloth cutting program for executing cloth cutting, and the like.

The cloth cutting program is provided with a detection mode for detecting a position where the scalpel receiver 31 and the scalpel 32 coincide, and a cloth cutting mode for performing cloth cutting based on the detection position detected in the detection mode. .

Before describing the detection mode, the encoder 55 will be described.

For example, when the pulse motor 34 is driven in a two-phase half-step and driven at a resolution of 400 pulses / rotation, the encoder 55 attached to the pulse motor 34 is also divided into 400. Is used. As shown in Fig. 5 showing the A-phase output signal and the B-phase output signal of the encoder 55, each of the A-phase and B-phase rises and falls in the encoder signal corresponding to one pulse of the pulse motor 34. do. By counting the rising and falling edges of each of the A and B phases, the signal value of the encoder 55 is counted by four multiplications. That is, when the pulse motor 34 drives normally by one pulse, the encoder 55 counts four, but when the pulse motor 34 does not drive normally, there is a deviation in the count value of the encoder 55. As a result, a rotation amount detector for detecting the rotation amount of the pulse motor 34 is configured.

In Fig. 6, as a characteristic of the pulse motor 34, the maximum torque is reached when the input pulse and the output pulse differ from each other by 2 (8 in the deviation amount of the encoder 55). (I) become

In addition, when a deviation occurs between the detection result of the encoder 55 and the input pulse, a deviation occurs in the rotation of the pulse motor 34 at that point, that is, a matching point between the scalpel receiver 31 and the scalpel 32 can be detected. It becomes possible.

By using this, the detection mode is executed. In the detection mode, the control unit 50 rotates the pulse motor 34 at a predetermined speed while counting the number of pulses of the pulse motor 34 when the scalpel receiving unit 31 and the scalpel 32 approach the home position. As a result, the drive shaft 33 and the shank moving mechanism 35 are driven to bring the scalpel receiver 31 and the scalpel 32 closer.

In this proximity, the control unit 50 rotates at a higher speed (third set speed) than the predetermined speed until the count value becomes the number of non-contact pulses in which the female receiving unit 31 and the female 32 do not come into contact with each other. When the value is the number of non-contact pulses, the pulse motor 34 is rotated at a predetermined speed (lower than the third set speed). Here, the predetermined speed is a speed at which no deviation occurs between the input pulse of the pulse motor 34 and the detection result of the encoder 55, and both sides are not damaged when the mass receiving part 31 and the mass 32 are in contact with each other. More preferably, it is a speed.

If the deviation from the detection result from the encoder 55 and the input pulse of the pulse motor 34 occurs, the controller 50 stops the pulse motor 34 and sets the count value at the stop as the number of coincidence pulses. Remember

In the cloth cutting mode, the controller 50 counts the number of pulses of the pulse motor 34 when the mass receiving unit 31 and the scalpel 32 approach the home position, and when the count value becomes the number of coincidence pulses. Until now, the pulse motor 34 is rotated at a high speed (first set speed). Then, the pulse motor 34 is rotated at a second set speed lower than the first set speed from the number of coincidence pulses to the predetermined number of pulses. As a result, the drive shaft 33 and the shank moving mechanism 35 are driven to bring the scalpel receiving portion 31 and the scalpel 32 close to each other to cut the cloth. Here, the predetermined number of pulses is the number of pulses that can apply the pressing force to the cloth until the cloth receiving portion 31 and the blade 32 match, and then reliably cut the cloth sandwiched between both sides.

Next, the operation of the present embodiment will be described.

First, when the initial space | interval of the scalpel receiving part 31 and the scalpel 32 becomes large by cutting the scalpel receiving part 31, an operator operates the operation panel 57, and inputs the start instruction of a detection mode.

When the detection mode is input, as shown in Fig. 7, in step S1, the controller 50 resets the count value of the number of pulses of the pulse motor 34 to 0 and starts counting.

In step S2, the controller 50 moves the pulse motor 34 at a high speed (third set speed: for example 4000pps) until the count value becomes the number of non-contact pulses (for example, 1000 pulses) input from the operation panel 57. Then, the scalpel receiving portion 31 is approached to the scalpel 32 from the origin position. Here, until the count value reaches the number of non-contact pulses from 0, as shown in Fig. 8, there is an acceleration region T1, a constant speed region (third set speed T2), and a deceleration region T3, and the non-contact pulse. Is set to slow down to a low speed (predetermined speed: 1000 ppm). In the acceleration area T1, the detection result of the encoder 55 gradually increases gradually with respect to the number of input pulses, and in the constant speed area T2, the maximum value (e.g. 8) at which the deviation amount does not cause a step out is obtained. In the deceleration area T3, it gradually decreases gradually until the deviation amount reaches zero.

In step S3, the controller 50 inputs one pulse to the pulse motor 34.

In step S4, the controller 50 maintains only the period (1ms) during which the driving by one pulse is completed, and rotates the pulse motor 34 by only one pulse.

In step S5, the controller 50 detects the deviation amount between the detection result and the input pulse of the pulse motor 34 based on the detection result of the encoder 55 in the rotational drive in step S4.

In step S6, the controller 50 determines whether or not the amount of deviation detected in step S5 is 0, and if it is 0, moves to step S3, and if not 0 (T4 in Fig. 8), goes to step S7. To fulfill. In addition, when the steps S3 to S6 are repeated, the rotational speed of the pulse motor 34 is maintained at a low speed.

In step S7, the control unit 50 stops the pulse motor 34, and stores the count value at that time as the number of matching pulses.

In step S8, the control unit 50 drives the pulse motor 34 at high speed until the mass receiving unit 31 returns to the home position. The detection mode is thus completed.

After completion of the detection mode, when the start instruction of the cloth cutting mode is input to the operation panel 57 by the operator, as shown in Fig. 9, in step S11, the control section 50 determines the number of pulses of the pulse motor 34. Reset the count to zero and start counting.

In step S12, the controller 50 moves the pulse motor 34 at a high speed (first set speed: 4000 ppm, for example) until the count value becomes the number of coincidence pulses, and moves the scalpel receiver 31 and the scalpel 32 to each other. Approach from home position. Also in this case, the acceleration area T5, the constant speed area T6, and the deceleration area T7 become the number of matching pulses until the count value reaches the number of matching pulses from zero. In this case, the speed is reduced to a low speed (second set speed: 1000 pps).

In step S13, the controller 50 drives the pulse motor 34 until the count value reaches a predetermined number of pulses.

In step S14, the control unit 50 waits only a period (50ms) until the pulse motor 34 rotates to the predetermined number of pulses to cut the cloth.

In step S15, the controller 50 drives the pulse motor 34 at high speed until the mass receiving part 31 returns to the home position. Thus, the cloth cutting mode is completed.

As described above, according to the present embodiment, when the cloth cutting mode is executed, the pulse motor 34 rotates at high speed up to the number of coincidence pulses detected by the detection mode, so that the operating section at high speed can be made very wide. have. If the detection mode is executed after the scalpel receiving part 31 is wiped, even if the distance between the scalpel receiving part 31 and the scalpel 32 is widened due to the maintenance, the operation section at low speed is greatly suppressed and the cycle The time can be shortened.

In addition, since the pulse motor 34 is rotated at a high speed until the number of non-contact pulses when the detection mode is executed, the time taken for the detection mode can be shortened.

In addition, this invention is not limited to the said embodiment, Of course, it can change suitably.

For example, in this embodiment, although the case receiving part 31 is provided in the linear motion shaft 45, and the scalpel 32 is provided in the bed part 2, it demonstrated and demonstrated, but the scalpel in the linear motion shaft 45 was illustrated. May be provided, and the scalpel receiving part may be installed in the bed part 2.

Moreover, in the said embodiment, the operator can input the predetermined speed of the detection mode, the 3rd setting speed, and the 1st setting speed and the 2nd setting speed of the cloth cutting mode from the operation panel 57. FIG.

When the predetermined speed of the detection mode and the second setting speed of the cloth cutting mode coincide with each other, and the first setting speed of the cloth cutting mode and the third setting speed of the detection mode coincide with each other, The input operation can be simplified.

In the above embodiment, when the detection mode is re-executed, the time can be shortened by executing the detection mode with the first set speed and the second set speed set first.

In the present embodiment, the case where the scalpel receiver 31 and the scalpel 32 are directly matched when the detection mode is executed has been described by way of example. However, the scalpel receiver 31 and the scalpel ( The coincidence position with 32 may be detected. If the mating position is detected with the cloth sandwiched, the mating position in consideration of the thickness of the cloth can be detected. As a result, by removing the fabric, it is possible to prevent out-of-gassing and to ensure reliable cutting.

In addition, in this embodiment, although the encoder 55 was demonstrated as an example of the rotation amount detection part which concerns on this invention, a resolver, a tachogenerator, etc. can also be used as this rotation amount detection part.

In addition, the type of pulse motor, the resolution, and the resolution of the encoder are not limited to 400 divisions.

In this embodiment, the reference value for applying the pressing force to the cloth in the cloth cutting mode is defined as the number of pulses (predetermined number of pulses), but it is also possible to define the deviation amount of the encoder 55. For example, after the number of matching pulses is reached, the pressing force is applied to the cloth by driving the pulse motor 34 until the amount of deviation reaches a predetermined value.

In addition, although the sewing machine which performs the eyelet buttonhole stitch was demonstrated in this embodiment, you may implement it in the sewing machine which performs the eyelet stitch which does not have a straight hole part, or the buttonhole stitch which consists only of a straight hole part.

Claims (3)

Scalpel 32 with a knife tip, A scalpel receiving portion 31 disposed to face the scalpel and cutting the cloth in cooperation with the knife tip of the scalpel; A moving mechanism 35 connected to one side of the scalpel or the scalpel to move the shank; A drive shaft 33 rotatably supported by the sewing machine frame and connected to the moving mechanism to move and contact one of the scalpel and the female receiving part to the other by rotation; A pulse motor 34 connected to the drive shaft; Rotation amount detection unit 55 for detecting the rotation amount of the pulse motor, A control unit 50 for controlling the pulse motor based on a detection result of the rotation amount detection unit, The control unit, When approaching the scalpel and the female receiving part, the pulse motor is rotated at a predetermined speed from the origin position, and the pulse motor is stopped when there is a deviation between the detection result from the rotation amount detecting part and the input pulse of the pulse motor. A detection mode for storing the detection result from the rotation amount detection unit at the time of stop as a number of matching pulses; When approaching the scalpel and the female receiving part, the pulse motor is rotated at a high speed of the first set speed until the detection result from the rotation amount detection unit becomes the number of coincidence pulses, and the detection result from the rotation amount detection unit And a cloth cutting mode for rotating the pulse motor at a low speed of a second set speed until the number of coincidence pulses exceeds a predetermined number of pulses. The method of claim 1, When the detection mode is executed, the control unit counts the number of pulses of the pulse motor, and is higher than the predetermined speed of the detection mode until the count value becomes the number of non-contact pulses in which the scalpel and the female receiving unit do not contact. Rotate the pulse motor at a predetermined speed in the detection mode by rotating the pulse motor at a third set speed and the count value becomes a non-contact pulse number, thereby driving the drive shaft and the moving mechanism to bring the scalpel and the scalpel part closer; And if the deviation is detected in the detection result from the rotation amount detecting unit, the pulse motor is stopped and the count value at the time of stopping is stored as the number of coincidence pulses. The method according to claim 1 or 2, The buttonhole sewing machine, characterized in that the predetermined speed of the detection mode and the second set speed of the cloth cutting mode coincide, and the first set speed of the cloth cutting mode and the third set speed of the detection mode coincide. Cloth cutting device.