JP2003181170A - Buttonholing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten the remaining lengths of a bobbin thread and a core thread and to surely cut the bobbin thread and the core thread. <P>SOLUTION: An eyelet buttonholing machine 1 is provided with freely vertically movable cloth pressers 55 and 56, a knife receiver 9 freely movable between an elevated position and a cutting position, a cloth cutting knife 11, an upper knife 61 and a lower knife 62 provided on a feed plate 58, an air cylinder 65 driving the upper knife 61 and the lower knife 62 from an opening position to a closing position, a presser driving cylinder 59 vertically driving the cloth pressers 55 and 56, a cloth cutting motor 8 vertically driving the knife receiver 9, and a controller 100 controlling the cloth cutting motor 8, the air cylinder 65 and the presser driving cylinder 59. After the cloth pressers 55 and 56 are elevated after sewing and eyelet hole formation, when the knife receiver 9 is positioned at a prescribed height between the elevated position and the cutting position, the controller 100 operates the air cylinder 65 and the upper knife 61 and the lower knife 62 are moved to the closing position. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buttonhole overlock sewing machine for forming buttonholes in a cloth and performing overlocking around the buttonholes before or after the buttonholes are formed.

[0002]

2. Description of the Related Art A so-called eyelet buttonhole sewing machine is one in which eyelet holes are formed on a cloth placed on a feed table, and overlock stitches are formed around the eyelet holes before or after the eyelet holes are formed. In the eyelet buttonhole stitch sewing machine, the looper mechanism is operated in cooperation with the vertical movement and swinging motion of the needle to form a stitched stitch made of the upper thread, the lower thread and the core thread on the cloth. Further, the cloth cutting knife descends from above the cloth toward the cloth, and the cloth cutting knife is aligned with the knife receiver arranged below the cloth, whereby eyelet holes are formed in the cloth. Also,
The eyelet buttonhole sewing machine is equipped with a presser foot mechanism so that the cloth can be firmly held on the feed bar during sewing or cloth cutting.The cloth presser mechanism is provided between the presser foot of the cloth presser mechanism and the feed bar. Is pinched.

Since it is necessary to cut the upper thread, the lower thread and the core thread after sewing, the eyelet buttonhole sewing machine has a lower thread cutting scissors (composed of an upper knife and a lower knife) and an upper thread cutting knife. The upper thread is cut by the upper thread cutting knife, and the lower thread and the core thread are cut by the lower thread cutting scissors.

By the way, in order to shorten the remaining length of the upper thread (the length from the end point of overlock stitching to the cutting point),
The needle thread cutting knife is provided in the looper mechanism. On the other hand, in order to shorten the remaining length of the bobbin thread and the core thread, the bobbin thread cutting scissors are provided on the feed base, and the cloth is placed between the lower knife and the presser foot during sewing and cloth cutting. It is pinched.

That is, at the time of sewing and cloth cutting, the lower knife is pressed by the cloth retainer. To ensure that the lower knife can move after sewing and cloth cutting,
It is necessary to release pressing the lower knife with the cloth presser when cutting the lower thread and the core thread. Therefore, after the cloth presser rises after the sewing and the cloth cutting are completed, the upper knife and the lower knife are closed to cut the lower thread and the core thread.

[0006]

However, in the conventional eyelet buttonhole sewing machine, since the presser foot rises when the bobbin thread and the core thread are cut, the cloth floats up or the weight of the portion protruding from the feed bar is increased. The cloth may be misaligned. Therefore, the remaining length of the lower thread and the core thread may become longer, and the lower thread and the core thread may not be cut. Therefore, an object of the present invention is to shorten the remaining length of the lower thread and the core thread, and to reliably cut the lower thread and the core thread.

[0007]

In order to solve the above-mentioned problems, the invention according to claim 1 uses a lower knife (for example, lower knife 62) as shown in FIG. 1, FIG. 2 or FIG. Before forming the buttonhole overlock seam on the sewn object while sandwiching the sewn object (for example, the cloth 200) placed above between the cloth presser (for example, the right cloth presser 56) and the lower knife. Alternatively, later, by lowering one member of the cloth cutting knife (for example, the cloth cutting knife 11) or the knife receiver (for example, the knife receiver 9) toward the other member, a button hole (for example, for the sewing object) is formed. , Eyelet holes), and after forming the buttonhole overlock stitch and the buttonhole, raise the cloth presser to remove the upper knife (for example, upper knife 61) and the lower knife arranged below the article to be sewn. Extending from the material to be sewn by closing them together In a buttonhole overlock sewing machine (for example, an eyelet overlock stitch sewing machine 1) for cutting a lower thread, a cloth cutting drive means (for example, a cloth cutting motor) for moving the one member up and down between a rising position and a cutting position. 8)
And a thread trimming drive means (for example, an air cylinder 65) that reciprocates the upper knife and the lower knife between an open position in which they are open and a closed position in which they are closed, and the cloth trimming drive means and the thread trimmer. By controlling the driving means, when the one member of the cloth cutting knife or the knife receiver is located in the vicinity of the upper surface of the workpiece between the rising position and the cutting position, the upper knife and the lower knife are moved. And a control unit (for example, the control device 100) for moving from the open position to the closed position.

According to the first aspect of the present invention, when one member of the cloth cutting knife or the knife receiver is located near the upper surface of the workpiece between the rising position and the cutting position, the upper knife and the lower knife are Move from the open position to the closed position. Therefore, even if the presser foot is raised, the sewing object hits one member, so that the sewing object is prevented from floating above the one member, and further the sewing object is prevented from shifting. . Therefore, since the sewn object is prevented from rising or shifting, the lower thread is not pulled out, and the lower thread is cut by the upper knife and the lower knife with a short remaining length. Further, since the floating or shifting of the sewn object is prevented, the cutting position of the lower thread becomes uniform, so that the lower thread is surely cut and the occurrence of defective cutting is suppressed.

According to a second aspect of the present invention, as shown in FIG. 4, for example, in the buttonhole overedger sewing machine according to the first aspect, the upper knife and the lower knife are moved from the open position to the closed position. A setting means for setting the position of one member (for example, the operation panel 106 and the control device 100) is provided, and when the control means places the one member at the position set by the setting means. The upper knife and the lower knife are moved from an open position to a closed position.

According to the second aspect of the present invention, when the position of one member (either the cloth cutting knife or the knife receiver) is set when the upper knife and the lower knife move from the open position to the closed position, When one member is located at the set position, the upper knife and the lower knife move from the open position to the closed position. That is, since the position of one member when the upper knife and the lower knife move can be set, the workpiece hits one member at an appropriate position even for workpieces of various thicknesses, Applicable to various thicknesses. Therefore, the bobbin thread is reliably cut with the short remaining thread for the sewing object of any thickness.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. As shown in FIG. 1, an eyelet buttonhole sewing machine 1 to which the present invention is applied includes a bed portion 2,
The vertical body portion 3 standing on the rear end of the bed portion 2 and the vertical body portion 3
Arm portion 4 extending from the upper part of the arm portion substantially parallel to the bed portion 2, a needle bar 13 extending downward from a front end portion of the arm portion 4, and a needle 12 attached to a lower end portion of the needle bar 13.
And a looper mechanism 6 provided immediately below the needle 12 in the bed 2, and a control device 100 for controlling the entire sewing machine 1.
(Illustrated in FIG. 4), an operation panel 106 for inputting data to the control device 100, and a presser switch 107 used for instructing the start of sewing.

Further, the eyelet buttonhole sewing machine 1 is provided with a needle bar vertical movement mechanism (not shown), a needle swing mechanism (not shown), and a looper mechanism 6. The needle bar vertical movement mechanism transmits the power of the sewing machine motor 108 (shown in FIG. 4) to the needle bar 13 to drive the needle bar 13 and the needle 12 up and down. The needle swinging mechanism applies the power of the sewing machine motor 108 to the needle bar 1.
3, and the needle bar 13 and the needle 12 are swung back and forth from side to side.

The looper mechanism 6 includes two looper spreaders 1 provided in the bed portion 2 immediately below the needle bar 13.
4, 14 and a swivel mechanism 7 for rotating the lupus spreaders 14, 14 around the vertical line when the round hole portions of eyelet holes (a kind of button hole) are sewn. The looper spreaders 14 and 14 operate in synchronization with the vertical movement and the needle swinging motion of the needle bar 13, and thereby cooperate with the needle 12 to perform overlock stitch sewing on the cloth (sewn product) 200 around the eyelet holes. Is. The looper mechanism 6 includes a cloth 200 and a needle 1.
An upper thread cutting knife is provided which cuts the upper thread laid between the upper and the lower thread 2 after overstitching.

Further, the eyelet buttonhole sewing machine 1 includes a cloth 2
It is equipped with a feed table 5 on which 00 is placed. The feed table 5 is provided in the front part of the bed part 2 so as to be movable back and forth and left and right. The feed table 5 is an X feed motor 109 (shown in FIG. 4).
Is driven back and forth by the Y feed motor 11
0 (shown in FIG. 4) drives left and right.

Further, as shown in FIGS. 1 and 2, the eyelet buttonhole sewing machine 1 has a presser device 50 for holding the cloth 200 at the time of overlock stitching, and a eyelet hole is formed in the cloth 200 after overlock stitching or before overlock stitching. Cloth cutting device 10 and cloth 20
0 and the looper mechanism 6 are provided, and a lower thread cutting device 60 for cutting the lower thread and the core thread.

The presser device 50 includes a left feed plate 51, a right feed plate 52, a left presser arm 53, a right presser arm 54, a left cloth presser 55, a right cloth presser 56, a left receiving plate 57, and Right back plate 5
8 and a presser drive cylinder 59 (shown in FIG. 4).

The left feed plate 51 and the right feed plate 52 constitute the upper surface of the feed table 5 and are fixed to the feed table 5. In plan view, the left feed plate 51 and the right feed plate 52 are
The needle plates 21 arranged immediately below the needle bar 13 are arranged symmetrically with respect to the left and right with respect to the needle plate 21. Left presser arm 53
The base end of the left feed plate 51 is attached to the rear end of the left feed plate 51 so as to be rotatable about the axis in the left-right direction. Left presser arm 53
A left presser foot 55 is swingably attached to the tip of the. Similarly, the base end portion of the right presser arm 54 is attached to the rear end portion of the right feed plate 52 so as to be rotatable about the axis in the left-right direction, and the right cloth presser 56 is attached to the tip end portion of the right presser arm 54.
Is swingably attached. The left receiving plate 57 is fixed to the right edge of the left feed plate 51 on the upper surface of the left feed plate 51. The right receiving plate 58 is fixed to the left edge of the right feeding plate 52 on the upper surface of the right feeding plate 52. The length of the right receiving plate 58 in the front-rear direction is shorter than the length of the left receiving plate 57 in the front-rear direction.

In the above-described presser device 50, the left and right presser arms 53, 53 are driven by the presser drive cylinder 59 which is an air cylinder.
By rotating 54 up and down, the left and right cloth pressers 5
5,56 are designed to move up and down. Left back plate 57
When the cloth 200 is placed on the right receiving plate 58 and the left and right cloth pressers 55 and 56 are lowered, the cloth 200 is moved to the left receiving plate 57.
And the left support plate 55 and the right support plate 5
It is clamped between 8 and the right presser foot 56.

The lower thread cutting device 60 comprises an upper knife 61, a lower knife 62, a cam piece 63, a link mechanism 64, and an air cylinder (that is, thread trimming drive means) 65. The rear end of the lower knife 62 is arranged adjacent to the front end of the right receiving plate 58, and the thickness of the lower knife 62 is substantially equal to the thickness of the right receiving plate 58. The left edge of the lower knife 62 is a blade. Further, the front and rear intermediate portions of the lower knife 62 are made rotatable by the step screw 66, and the lower knife 62 is attached to the upper surface of the right feed plate 52. The lower knife 62 is provided with a cam contact portion 67 extending forward.

The upper knife 61 is disposed rearward of the rear end edge of the left cloth presser 55 and overlaps the lower knife 62. The intermediate portion of the upper knife 61 is made rotatable by the step screw 66, and the upper knife 61 is attached to the upper surface of the right feed plate 52. The tip of the upper knife 61 extends leftward from the left edge of the right feed plate 52, and the tip serves as a blade. Further, the upper knife 61 is provided with a cam contact portion 68 extending forward. The cam contact portion 68 is arranged to the left of the cam contact portion 67 of the lower knife 62.

The cam piece 63 is elongated in the front-rear direction and is arranged between the cam contact portion 67 and the cam contact portion 68. The cam piece 63 is in contact with the left edge of the cam contact portion 67 and is in contact with the right edge of the cam contact portion 68. Cam piece 6
The front and rear intermediate portions of 3 are made rotatable by a step screw 69 and attached to the upper surface of the right feed plate 52. In addition,
Torsion springs 70, 71 are provided on the upper surface of the right feed plate 52, and the torsion springs 70, 71 are arranged in the direction in which the cam contact portion 67 and the cam contact portion 68 sandwich the cam piece 63. The cam contact portion 68 is biased.

The link mechanism 64 includes a link piece 72, a link piece 73, and a link arm 74. One end of the link piece 72 is rotatably attached to the rear end of the cam piece 63. The other end of the link piece 72 is rotatably attached to one end of the link piece 73. The other end of the link piece 73 is fixed to one end of the link arm 74. The other end of the link piece 73 and one end of the link arm 74 are rotatably attached to the right feed plate 52.

The other end of the link arm 74 has an air cylinder 6
5 output rod 75. Air cylinder 65
Is for moving the output rod 75 forward and backward, and the output rod 7
The link arm 74 rotates to the left and right around one end of the link arm 74 as the arm 5 moves forward and backward.

In the above bobbin thread cutting device 60, the right cloth presser 5
When 6 is lowered, the cloth is clamped between the right receiving plate 58 and the right cloth presser 56, and the cloth is further placed on the lower knife 62,
The cloth is clamped between the right cloth presser 56 and the lower knife 62. Here, the cloth 200 is arranged above the upper knife 61 and the lower knife 62.

Further, the air cylinder 65 is connected to the output rod 75.
Is fed to the right, the cam piece 63 rotates clockwise about the step screw 69 in plan view, and the cam contact portion 67 and the cam contact portion 68 are spread by the cam piece 63. As a result, in plan view, the lower knife 62 rotates counterclockwise about the step screw 66, and the upper knife 61 rotates clockwise about the step screw 66, so that the upper knife 61 and the lower knife 62 move. Move to a closed position that is closed to each other. By this operation, the bobbin thread and the core thread hung on the cloth from the needle plate 21 are cut.
On the other hand, when the air cylinder 65 sends the output rod 75 to the left, the cam piece 63 rotates counterclockwise in plan view and the cam contact portions 67 and 68 are closed by the torsion springs 70 and 71. . As a result, the lower knife 62 rotates in the clockwise direction, the upper knife 61 rotates in the counterclockwise direction, and the upper knife 61 and the lower knife 62 move to the open position where they are opened to each other.

As shown in FIGS. 1 and 3, a cloth cutting device 1
Reference numeral 0 denotes a knife receiver 9 which is provided behind the needle bar 13 so as to be vertically movable, and a feed plate 5 provided directly below the knife receiver 9.
1, a cloth cutting knife 11 provided below the knife 1, and a knife driving mechanism 15 for driving the knife receiver 9 up and down.

The knife driving mechanism 15 includes a cloth cutting motor (that is, cloth cutting driving means) 8, a ball screw 24, links 27, 27, a lever 28, a rotary shaft 26, and a gear 40.
And a rack member 41 and the like, and are configured as follows. That is, the cloth cutting motor 8 which is a stepping motor is fixed to the rear portion of the bed portion 2, and the drive take-out shaft 16 thereof extends upward. Cloth cutting motor 8
The pinion 31 is fixed to the drive take-out shaft 16 of
The pinion 31 meshes with the gear 32. Gear 3
2 is fixed to the lower end of a ball screw 24 extending vertically. The ball screw 24 is rotatable.
A nut 33 meshes with the ball screw 24, and the nut 33 is fixed to a base 34. The base 34 is vertically movable and supported by a guide 37. The guide 37 extends vertically and is fixed in the vertical body portion 3. The guide 37 guides the base 34 in the vertical direction, and prevents the base 34 from rotating around the ball screw 24.

One end of the link 27 is attached to the base 34 so as to be rotatable about an axis in the front-rear direction.
The other end of the link 27 is attached to one end of a lever 28 so as to be rotatable around a longitudinal axis. The other end of the lever 28 is fixed to the rear end of the rotary shaft 26. The rotary shaft 26 extends in the front-rear direction and is rotatably provided in the arm portion 4. A gear 40 is fixed to the front end of the rotary shaft 26. On the other hand, a rack member 41 extending vertically is provided at the front end of the arm portion 4. The rack member 41 is vertically movable and supported by the arm portion 4, and the female receiver 9 is fixed to the lower end portion of the rack member 41. Further, the rack member 41 meshes with the gear 40.

In the above cloth cutting device 10, the rotation of the cloth cutting motor 8 is transmitted to the ball screw 24, and the rotational movement of the ball screw 24 is converted into the vertical movement of the base 34. Base 34
The vertical movement of the rotary shaft 26 is converted into a rotary motion of the rotary shaft 26 by the link 27 and the lever 28. Further, the rotational movement of the rotary shaft 26 is converted into vertical movement of the knife receiver 9 by the gear 40 and the rack member 41. That is, the cloth cutting motor 8
When is operated, the knife receiver 9 moves up and down. When the knife receiver 9 descends, the cloth is sandwiched between the knife receiver 9 and the cloth cutting knife 11, the cloth cutting knife 11 cuts the cloth 200, and eyelet holes are formed in the cloth 200.
The drive extraction shaft 16 of the cloth cutting motor 8 is provided with an origin detection sensor 105 that detects the origin position of the knife receiver 9 driven by the cloth cutting motor 8.

The control device 100 includes a CPU 101 and RA
The basic configuration is an arithmetic processing unit having an M102, a ROM 103, and a system bus connecting them.
Further, the control device 100 includes a drive circuit 104, which drives the CPU 10 via a system bus.
Connected to 1. A sewing machine motor 108, an air cylinder 65, a cloth cutting motor 8, a presser drive cylinder 59, an X feed motor 109, and a Y feed motor 110 are connected to the drive circuit 104.

The operation panel 106 is connected to the CPU 101 via an interface. Operation panel 106
Detects that it has been operated by an operator, and
It is output to the PU 101. Thereby, the operator can change the setting value of a predetermined setting item and input it by operating the operation panel 106. The presser foot switch 107 is the CPU 1 via the interface.
01 is connected. The presser switch 107 outputs an ON signal when pressed by an operator. It is output to the CPU 101.

The origin detection sensor 105 is connected to the CPU 101 via an interface. CPU 101
Can control the vertical position of the knife receiver 9 based on the detection signal output from the origin detection sensor 105 and the pulse number of the pulse signal output to the cloth cutting motor 8.

The ROM 103 stores a control program for controlling the eyelet buttonhole sewing machine 1 and control data used in this control program. CP
The U101 uses the RAM102 as a work area and the ROM10
It is possible to perform calculation according to the control program stored in No. 3 and various calculation processes based on a signal input from the operation panel 106 or the origin detection sensor 105.
Then, the CPU 101 can output a signal according to the calculation result to the sewing machine motor 108, the air cylinder 65, the cloth cutting motor 8, the presser drive cylinder 59, the X feed motor 109, and the Y feed motor 110. That is, the control device 100
By the calculation of the CPU 101, the sewing machine motor 108, the air cylinder 65, the cloth cutting motor 8, the presser drive cylinder 59,
The X feed motor 109 and the Y feed motor 110 can be controlled, and the sewing machine motor 108, the air cylinder 65, the cloth cutting motor 8, the presser drive cylinder 59, the X feed motor 109, and the Y feed motor 1 can be controlled at the timing according to the control program.
10 can be activated. The control device 100 can control the drive source of the upper thread cutting knife to operate the upper thread cutting knife at a predetermined timing.

The operation of the eyelet buttonhole sewing machine 1 configured as described above and the processing flow of the control device 100 will be described. This eyelet buttonhole sewing machine 1 has an operation of "first knife" for applying a button hole to cloth before eyelet buttonhole stitching and an operation of "back knife" for applying buttonhole to cloth after eyelet buttonhole stitching. You can do both. The operator operates the operation panel 106 in advance before the eyelet buttonhole sewing machine 1 performs sewing to select whether the eyelet buttonhole sewing machine 1 performs “first knife” or “rear knife”. Done.

First, referring to FIG. 5, the "tip knife" will be described. In the initial state, the feed table 5 is located at the foremost initial position in the front and rear movement range, and the upper knife 6
The 1 and the lower knife 62 are located in the open position where they are open from each other. Furthermore, in the initial state, as shown in FIG.
The knife receiver 9 is located at the uppermost raised position within the vertical movement range, and the cloth pressers 55 and 56 are located at the uppermost standby position within the vertical movement range. The height of the cloth pressers 55 and 56 at the standby position is substantially the same as the height of the knife receiver 9 at the raised position.

After the worker places the cloth 200 on the feed table 5, the worker pushes the presser foot switch 107 (step S
1: Yes). Then, the control device 100 operates the presser drive cylinder 59, and the presser drive cylinder 59 lowers the cloth pressers 55 and 56 (step S2). Accordingly, the cloth 200 is sandwiched between the left receiving plate 57 and the left cloth presser 55, sandwiched between the right receiving plate 58 and the right cloth presser 56, and further, the lower knife 62 and the right cloth presser 56 are sandwiched. Sandwiched between.

Next, the control device 100 causes the X feed motor 1
09 and the Y feed motor 110 are operated, the feed table 5 is moved to the cloth cutting position by the X feed motor 109 and the Y feed motor 110, and the feed table 5 is stopped at the cloth cutting position (step S3). The cloth cutting position is a position where the cloth cutting knife 11 is located between the left receiving plate 57 and the right receiving plate 58 in plan view.

Next, the control device 100 causes the cloth cutting motor 8 to
And the knife receiver 9 is lowered by the cloth cutting motor 8 (step S4). Then, FIG. 7B and FIG.
As shown in, the knife receiver 9 descends to a cutting position where it matches the cloth cutting knife 11. When the knife receiver 9 moves to the cutting position, eyelet holes are formed in the cloth 200. In addition,
The eyelet holes are formed in the overlying stitches that will be formed later.

Next, the control device 100 causes the cloth cutting motor 8 to
Is operated in the reverse rotation direction, the knife receiver 9 is moved to the initial raised position by the cloth cutting motor 8, and the knife receiver 9 is stopped at the raised position (step S5). Next, the control device 100 causes the X feed motor 109 and the Y feed motor 110 to
Is operated to move the feed table 5 to the sewing position (step S6). The sewing position is a position where the needle 12 is located between the left receiving plate 57 and the right receiving plate 58 in plan view.

Next, the controller 100 causes the sewing machine motor 1
08, X feed motor 109 and Y feed motor 110 are controlled to move needle 12 up and down and shake left and right, and lupus spreaders 14 and 14 operate in synchronization with the up and down movement of needle bar 13 and needle swing motion. Then, by further moving the feed table 5, overlock stitching is performed around the eyelet holes (step S7). Next, the control device 100 controls the drive source of the upper thread cutting knife, whereby the upper thread cutting knife operates,
The upper thread laid between the cloth 200 and the needle 12 is cut (step S8).

Next, the controller 100 causes the cloth cutting motor 8 to
And the knife receiver 9 is lowered by the cloth cutting motor 8 (step S9). While the knife receiver 9 is descending, the control device 100 determines the height of the knife receiver 9 based on the detection signal output from the origin detection sensor 105 and the pulse number of the pulse signal for driving the cloth cutting motor 8. That is,
The distance from the cutting position or the distance from the rising position is detected (step S10). When the control device 100 determines that the height of the knife receiver 9 has reached the predetermined height (step S10: Yes), the control device 100 stops the cloth cutting motor 8 and the knife receiver 9 reaches the predetermined height. To stop (step S11). The predetermined height is a position lower than the raised position and higher than the cutting position, and is a position slightly higher than the upper surface of the lower knife 62. That is, the knife receiver 9 located at the predetermined height is located near the upper surface of the cloth 200. Next, the control device 100 actuates the presser drive cylinder 59, and the presser drive cylinder 59 causes the cloth presser 5 to move.
5, 56 move to the standby position (step S12).
At this time, the knife receiver 9 is located at a position lower than the cloth pressers 55 and 56 (that is, the predetermined height is lower than the standby position).

Next, the control device 100 causes the air cylinder 6
5 is operated and the upper knife 61 is moved by the air cylinder 65.
The lower knife 62 and the lower knife 62 move to the closed position, and the lower thread and the core thread are cut by the upper knife 61 and the lower knife 62 (step S13). At this time, FIG. 7 (c) and FIG.
As shown in, the cloth 200 is slightly lifted from the receiving plates 57 and 58, but the cloth 200 hits the knife receiver 9 stopped at a predetermined height, and the cloth 200 is pressed downward by the knife receiver 9. In other words, the knife receiver 9 prevents the cloth 200 from being lifted above the knife receiver 9 located at a predetermined height, and prevents the cloth 200 from being displaced. The upper knife 61 and the lower knife 62 scissor the lower thread and the core thread at a position close to. Therefore, the so-called residual thread (the thread remaining on the cloth 200 side and extending from the sewing end point to the cutting point) is shortened.

Next, the control device 100 causes the air cylinder 6
5 is controlled, the rod of the air cylinder 65 is pulled and the torsion springs 70 and 71 move the upper knife 61 and the lower knife 62 to the open position where they are opened (step S).
14). Next, the control device 100 operates the cloth cutting motor 8 in the reverse rotation direction, and the knife receiver 9 is moved to the raised position by the cloth cutting motor 8 (step S15). Next, the control device 100 operates the X feed motor 109 and the Y feed motor 110, and the X feed motor 109 and the Y feed motor 109 are operated.
The feed motor 110 moves the feed table 5 to the initial position (step S16).

Next, the "posterior knife" will be described with reference to FIG. Even with the "rear knife", in the initial state, the feed table 5
Is located at the initial position, and the upper knife 61 and the lower knife 62 are
Is located at the open position, the knife receiver 9 is located at the raised position, and the cloth pressers 55 and 56 are located at the standby position.

After the worker puts the cloth 200 on the feed table 5, the worker pushes the presser foot switch 107 (step S2).
1: Yes), the control device 100 causes the presser drive cylinder 5
9 is operated, the cloth pressers 55 and 56 are lowered (step S22), and the cloth 200 is moved to the receiving plates 57 and 58 and the cloth pressers 55 and 56.
It is clamped between the lower knife 62 and the right cloth presser 56 while being clamped between the lower knife 62 and the right knife presser 56.

Next, the control device 100 causes the X feed motor 1
The 09 and Y feed motors 110 are operated, and the feed table 5 is moved to the sewing position by the X feed motor 109 and the Y feed motor 110 (step S23). Next, the control device 100 causes the sewing machine motor 108 and the X feed motor 109 to operate.
By controlling the Y feed motor 110 and the Y feed motor 110, the needle 12 moves up and down and is swayed to the left and right.
4, 4 and 14 operate in synchronism with the vertical movement of the needle bar 13 and the needle swing motion, and further, the feed table 5 moves, so that the cloth 200 is over stitched (step S24). Next, the control device 100 controls the drive source of the upper thread cutting knife to cut the upper thread by the upper thread cutting knife (step S25).

Next, the control device 100 causes the X feed motor 1
The 09 and Y feed motors 110 are operated, the feed table 5 is moved to the cloth cutting position by the X feed motor 109 and the Y feed motor 110, and the feed table 5 is stopped at the cloth cutting position (step S26). Next, the control device 100 operates the cloth cutting motor 8 so that the knife receiver 9 is lowered by the cloth cutting motor 8 (step S27), and the knife receiver 9 is lowered to the cutting position where it matches the cloth cutting knife 11 ( Figure 7
(B) and shown in FIG. 9). By moving the knife receiver 9 to the cutting position, an eyelet hole is formed in the cloth 200 in the overlock stitch. Almost at the same time as the operation of the cloth cutting motor 8, the control device 100 operates the presser drive cylinder 59 to move the cloth pressers 55 and 56 to the standby position (step S2).
8).

Next, the control device 100 causes the cloth cutting motor 8
Is operated in the reverse rotation direction to raise the knife receiver 9 by the cloth cutting motor 8 (step S29). While the knife receiver 9 is rising, the control device 100 keeps the origin detection sensor 1
The height (that is, the distance from the cutting position or the distance from the rising position) of the knife receiver 9 is detected based on the detection signal output from 05 and the pulse number of the pulse signal that drives the cloth cutting motor 8. There is. When the control device 100 determines that the height of the knife receiver 9 has reached the predetermined height (step S30: Yes), the control device 100 causes the air cylinder 6 to operate.
5 is operated and the upper knife 61 is moved by the air cylinder 65.
The lower knife 62 and the lower knife 62 move to the closed position, and the lower thread and the core thread are cut by the upper knife 61 and the lower knife 62 (step S31). When the knife receiver 9 moves to the raised position, the control device 100 stops the cloth cutting motor 8 (step S32). As described above, in the case of the “rear knife”, since the upper knife 61 and the lower knife 62 are driven while the knife receiver 9 is rising, the cloth 200 hits the knife receiver 9 (FIG. 7 (c) and (Illustrated in FIG. 8). This prevents the cloth 200 from floating above the knife receiver 9 and prevents the cloth 200 from slipping off. Therefore, the cloth receiver 200 is prevented from moving up at a position relatively close to the cloth 200. The knife 61 and the lower knife 62 scissor the lower thread and the core thread. Therefore, the so-called residual thread becomes shorter. Further, since the upper knife 61 and the lower knife 62 are driven while the knife receiver 9 is being raised, the cycle time for one buttonhole overedging can be shortened.

When the knife receiver 9 is in the raised position, the control device 100 controls the air cylinder 65 to pull the rod of the air cylinder 65, and the torsion springs 70 and 71 open the upper knife 61 and the lower knife 62 from each other. To the open position (step S33). Then, the control device 1
00 operates the X feed motor 109 and the Y feed motor 110, and the feed table 5 moves to the initial position (step S34).

As described above, when the knife receiver 9 is positioned at a predetermined height, whether it is the "leading knife" or the "rear knife", the controller 100 operates the air cylinder 65 to cause the lower thread and the core to move. The thread is cut by the upper knife 61 and the lower knife 62. By the way, in the present embodiment, the height (that is, the value of the predetermined height) of the knife receiver 9 when the control device 100 operates the air cylinder 65 can be set.

That is, the above step S1 or step S
Before 21, the operator can input the value of the predetermined height by operating the operation panel 106 in advance. When the operator inputs the value of the predetermined height, the control device 100 temporarily stores the value in the RAM 102 and sets the value. Then, in step S10 or step S30, when the height of the knife receiver 9 reaches the value stored in the RAM 102, the control device 100 operates the air cylinder 65,
The upper knife 61 and the lower knife 62 move from the open position to the closed position. Since the height of the knife receiver 9 during the operation of the air cylinder 65 can be set, the cloth hits the knife receiver 9 at an appropriate height even when the cloth has various thicknesses, and cloths of various thicknesses can be obtained. It is possible to respond.

As described above, in the present embodiment, since the right cloth presser 56 rises after the eyelet hole overholstering and after the formation of the eyelet holes (step S12 or step S28), the right cloth presser 56 is not obstructed. , Upper knife 61 and lower knife 6
The two can move so as to close each other. The cloth pressers 55 and 56 rise to lift the cloth 200 to some extent, but the cloth 200 hits the knife receiver 9 located at a predetermined height, and the cloth 200 is prevented from rising above the knife receiver 9. Therefore, since the lower thread and the core thread are not pulled out from the looper mechanism 6, it is possible to shorten the remaining length and cut the lower thread and the core thread.

When the cloth 200 hits the knife receiver 9 located at a predetermined height, the cloth 200 is prevented from being displaced by the weight of the cloth 200 protruding from the feed table 5 as a resistance. By preventing the cloth 200 from rising and shifting, the cutting positions of the lower thread and the core thread become uniform, so that the lower thread and the core thread are reliably cut and the occurrence of defective cutting is suppressed. Further, conventionally, when the bobbin thread and the core thread are cut, the cloth is manually held, but such trouble can be omitted.

In the case of the "rear knife", the knife receiver 9
Since the upper knife 61 and the lower knife 62 move from the open position to the closed position during the ascent of the eye, the eyelet buttonhole sewing machine 1
The series of operations is performed simultaneously. Therefore, a series of cycle time for sewing is shortened.

The present invention is not limited to the above-described embodiment, and within the scope of the present invention,
Various improvements and design changes may be made. For example,
The present invention is applicable not only to eyelet buttonhole buttonhole sewing machines, but also to sleep eye buttonhole buttonhole sewing machines.

In the case of the "rear knife", the upper knife 61 and the lower knife 62 start to close each other while the knife receiver 9 is moving upward (step S31), but the knife receiver 9 moves up to a predetermined height. Then, after stopping, the upper knife 61 and the lower knife 62
May close each other. In this case, the cycle time cannot be shortened, but conversely, since the knife receiver 9 stops, the cloth 200 surely hits the knife receiver 9 and the cloth 200 is prevented from floating further.
The lower thread and the core thread are surely cut by the upper knife 61 and the lower knife 62.

Further, in the case of the "tip knife", the knife receiver 9 once stops at the elevated position (step S5) and then descends to a predetermined height (step S9), but the knife receiver 9 is sewn. If it does not hinder the case (step S6 etc.), the knife receiver 9 may be stopped at a predetermined height in step S5.

Further, although the knife receiver 9 was moved up and down, conversely, the cloth cutting knife 11 is attached to the rack member 41, the knife receiver 9 is arranged in the bed portion 2, and the cloth cutting knife 11 is moved. May move up and down.

Further, when the knife receiver 9 is located at a predetermined height, the upper knife 61 and the lower knife 62 move to a position where they close each other.
When the 6 is positioned at a predetermined height, the upper knife 61 and the lower knife 6
You may move to the position where 2 mutually closes. In this case, the upper and lower drive sources for the cloth pressers 55 and 56 are preferably motors rather than air cylinders. This is because if the motor is a motor, it is possible to stop the cloth pressers 55, 56 between the holding position where the cloth 200 is clamped by the cloth pressers 55, 56 and the standby position.

The drive source of the upper knife 61 or the lower knife 62 or the drive source of the cloth pressers 55 and 56 is not limited to the air cylinder, but may be a solenoid or a motor.

[0061]

According to the first aspect of the present invention, even if the presser foot is raised, the work to be sewn hits one member, so that the work to be sewn is prevented from floating above the one member. In addition, the sewn object is prevented from shifting. Therefore, the lower thread is not pulled out, and the upper thread and the lower knife cut the lower thread with a short remaining length.
Further, by preventing the floating or shifting of the sewn object, the cutting positions of the lower thread become uniform, so that the lower thread is reliably cut.

According to the second aspect of the present invention, since the position of one member when the upper knife and the lower knife move can be set, it is possible to set an appropriate position for objects to be sewn of various thicknesses. Thus, the cloth hits one member and can be applied to the sewn objects of various thicknesses. Therefore, the bobbin thread is reliably cut with the short remaining thread for the sewing object of any thickness.

[Brief description of drawings]

FIG. 1 is a view showing a specific mode of an eyelet buttonhole stitch sewing machine to which the present invention is applied, and is a side view showing an internal configuration.

FIG. 2 is a plan view showing a specific mode of a feed base of the eyelet buttonhole sewing machine.

FIG. 3 is a rear view showing an internal configuration of the eyelet buttonhole sewing machine.

FIG. 4 is a block diagram showing a control system of the eyelet buttonhole sewing machine.

FIG. 5 is a flowchart showing a process of a control device for the eyelet buttonhole sewing machine.

FIG. 6 is a flowchart showing a process of the control device.

FIG. 7 is a view for explaining the operation of the eyelet buttonhole stitch sewing machine, and is a side view mainly showing a cloth cutting knife and a knife receiver.

FIG. 8 is a side view mainly showing a front end portion of the eyelet buttonhole stitch sewing machine when the knife receiver is located at a predetermined height.

FIG. 9 is a side view mainly showing a front end portion of the eyelet buttonhole stitch sewing machine when the knife receiver is located at a cutting position.

[Explanation of symbols]

1 Eyelet buttonholing stitch sewing machine (button hole stitching sewing machine) 8 Cloth cutting motor (cloth cutting driving means) 9 Knife receiver 10 Cloth cutting device 11 Cloth cutting knife 15 Knife driving mechanism 50 Presser device 55 Left cloth presser (cloth presser) 56 Right cloth presser (cloth presser) 57 Left receiving plate 58 Right receiving plate 59 Pressing drive cylinder 60 Lower thread cutting device 61 Upper knife 62 Lower knife 65 Air cylinder (thread cutting drive means) 100 Control device (control means, setting means) 105 Origin detection sensor 106 Operation panel (setting means) 200 cloth

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3B150 AA05 AA24 BA06 CC05 CE00                       CE27 EB10 EE03 EE07 EE16                       FH01 FH02 FH03 FH07 GD01                       GE03 GE12 JA02 JA03 JA11                       JA13 JA28 JA31 JA32 KA04                       LA82 LB01 LB02 MA02 MA09                       NA28 NA41 NA48 NB03 NB12                       NB16 NC03 NC11 NC18 PA03                       QA06 QA07

Claims (2)

[Claims] 1. A cloth cutting knife before or after forming a buttonhole stitch on the sewing object while sandwiching the sewing object placed above the lower knife between the presser foot and the lower knife. Alternatively, one of the knife receivers is lowered toward the other member to form a button hole in the sewn object, and the cloth presser foot is lifted after forming the buttonhole overlock seam and the buttonhole, In a buttonhole overlock sewing machine that cuts a lower thread extending from the sewing object by closing an upper knife and a lower knife arranged below the material to be sewn together, the one member is in a rising position and a cutting position. Cloth cutting drive means for moving up and down between the upper knife and the lower knife, and a thread cutting drive means for reciprocating the upper knife and the lower knife between an open position in which they are open and a closed position in which they are closed, and the cloth cutting drive means. as well as By controlling the thread trimming drive means, the upper knife and the upper knife when the one member of the cloth trimming knife or the knife receiver is located in the vicinity of the upper surface of the workpiece between the rising position and the cutting position. A buttonhole overedger sewing machine comprising: a control means for moving the lower knife from an open position to a closed position. 2. A setting means for setting the position of the one member when the upper knife and the lower knife move from the open position to the closed position, wherein the control means sets by the setting means. 2. The buttonhole stitch sewing machine according to claim 1, wherein the upper knife and the lower knife are moved from the open position to the closed position when the one member is located at the closed position.