KR100989741B1 - Sewing machine for button holing - Google Patents

Abstract

The buttonhole knitting machine of the present invention presses the work cloth placed on the feed table against the scalpel by lowering the first hammer to form a "bird-eye hole". The second hammer moves between the standby position of the rear upper part of the first hammer and the operating position overlapping the lower surface of the first hammer by the operation of the hammer moving mechanism. The movement path in the case of moving a 2nd hammer from a standby position to an operation position becomes a combination of a downward movement and a forward movement, and does not interfere with the cloth press which presses the workpiece | work cloth arrange | positioned at the feed table. When the second hammer is moved to the operating position to form a "closed button hole", it is not necessary to move the feed table to avoid interference with the cloth stopper. Therefore, the hole making process can be reduced and work efficiency can be improved.

Button hole sewing machine, bird eye shape hole, blocked button hole, hammer, scalpel

Description

Buttonhole sewing machine {SEWING MACHINE FOR BUTTON HOLING}

This invention is equipped with one scalpel and two hammers (1st hammer and 2nd hammer), presses a workpiece | work cloth to a scalpel by a 1st hammer, forms a "bird-eye hole", and processes it by a 2nd hammer. The button hole cutting sewing machine which presses a cloth on a scalpel and forms a "closed button hole."

The button hole cutting sewing machine is provided with the hammer apparatus for forming a button hole in a process cloth. The hammer device includes a scalpel fixed to the base frame of the sewing machine so as to face the lower surface of the working cloth, and a hammer facing the scalpel with the working cloth interposed therebetween. The hammer moves downward by the operation of the actuator to press the working cloth against the scalpel. By this press, a scalpel forms a buttonhole in a process cloth. Formation of a button hole by a hammer device may be performed before the start of hole cutting, or may be performed after the end of hole cutting.

The buttonhole cutting sewing machine described in Japanese Laid-Open Patent Publication No. 2001865 has two hammers (first hammer and second hammer). The first hammer has a shape that can be pressed against the entire scalpel, and the second hammer has a shape that can be pressed against a portion of the scalpel.

The 1st hammer is fixed to the front-end | tip part of the curved arm member, and is arrange | positioned above the scalpel. The air cylinder lowers the first hammer through the arm member. The rotary air cylinder is provided in the inner space of the arm member, and the second hammer is fixed to the output rotating body of the rotary air cylinder.

Normally, the second hammer is in the standby position above the first hammer. When the air cylinder is operated while the second hammer is in the standby position, the first hammer presses the working cloth on the whole scalpel to form a "bird-eye hole".

The second hammer moves to an operating position overlapping the lower surface of the first hammer by the rotation of the output rotor of the rotary air cylinder. When the air cylinder is operated while the second hammer is in the operating position, the second hammer presses the working cloth against a part of the scalpel to form a "closed button hole". The button hole cutting sewing machine is provided with the cloth presser which hold | maintains a process cloth on the upper surface of a conveyance board in the left and right both sides of the hole to be knit. With the above-described buttonhole sewing machine, after forming a bird-shaped hole knitting stitch on the fabric, it is possible to form a buttonhole knitting stitch clogged in another part of the fabric. After forming a bird eye-stitching stitch, the cloth pawl and the first hammer are raised. When the second hammer moves to the operating position after the rise, there is a problem that the second hammer interferes with the left and right cloth presses or the support members of the cloth presses. This is because the cloth stoppers are located on both sides of the first hammer.

In order not to interfere with a 2nd hammer, the above-mentioned buttonhole sewing machine performs the following operation | movement. After the end of the hole cutting, the transfer mechanism moves the transfer table forward. The cloth stopper moves from the side position opposite to the first hammer to the front position not facing the first hammer. A rotary air cylinder moves the second hammer to the operating position. Thereafter, the transfer mechanism moves the transfer table forward to form a "closed button hole". Thus, in the conventional buttonhole sewing machine, when forming a "closed buttonhole" using a 2nd hammer, it is necessary to reciprocate back and forth the conveyer of the processing cloth, and work efficiency will fall. There is.

An object of the present invention is to make it possible to move the second hammer quickly to the operating position irrespective of the position of the transfer table, to reduce the hole cutting process, and to increase the work efficiency.

The button-hole sewing machine of the invention of claim 1 is a scalpel having a cloth press that presses a fabric on a transfer table, and a scalpel disposed below the fabric that the cloth press presses, and the scalpel interposed therebetween. In the button-hole sewing machine provided with the 1st hammer facing upward of the said 1st hammer, the said 1st hammer descends and presses the said processing cloth to the said scalpel, and forms a buttonhole in a press part, Comprising: It differs from the said 1st hammer. The second hammer having the shape and the second hammer are moved between the standby position on the side where the feed table supports the cloth stopper and the operating position below the first hammer in the horizontal direction than the first hammer. The hammer movement mechanism is provided.

Normally, the second hammer is in the standby position on the side where the feed table supports the cloth stopper than the first hammer. When the button hole is formed in the fabric to be processed by the second hammer, the second hammer moves from the above-described standby position to the operation position below the first hammer by the operation of the hammer moving mechanism. The movement path of the second hammer between the standby position and the operating position does not interfere in the front-rear direction with the cloth stopper pressing the working cloth on the carriage.

The button hole cutting sewing machine of Claim 2 has the intermediate position and the said standby position which the said hammer movement mechanism makes a 2nd hammer, and the upper surface of the said 2nd hammer becomes lower than or equal to the lower surface of the said 1st hammer. The 1st drive mechanism which moves up and down between them, and the 2nd drive mechanism which moves back and forth between the said intermediate position and the said operating position are provided.

The second hammer can move quickly from the standby position to the operating position by a combination of the operations of the first drive mechanism and the second drive mechanism. The second hammer also reliably avoids interference with the cloth stopper and interference with the first hammer.

In the buttonhole sewing machine of the invention of claim 3, the first drive mechanism is constituted by an air cylinder for vertical movement, and the second drive mechanism is constituted by an air cylinder for forward and backward movement. The vertical movement air cylinder is fixed to the distal end of the piston rod of the front and rear movement air cylinder, and simply constitutes a hammer movement mechanism including the vertical movement air cylinder and the front and rear movement air cylinder.

In the buttonhole knitting machine of the invention of claim 4, the second hammer is fixed to the distal end of the piston rod of the vertical cylinder for air movement, and the hammer movement includes a second hammer, the vertical cylinder for moving the air, and the air cylinder for vertical movement. The apparatus can be configured simply.

According to the present invention, in the button hole knitting machine having the first hammer and the second hammer, the hole hammering step is not necessary because the movement path of the second hammer does not interfere with the cloth stopper, so that it is not necessary to move the feeder. It is effective in reducing work efficiency.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail with reference to drawings which show preferable embodiment.

As shown in Fig. 1, the buttonhole knitting machine 1 has a rectangular box-shaped bed stand 2 and a bed 3 arranged to be fitted into an opening in the upper portion of the bed stand 2. . In the rear part of the bed 3 (the right side of FIG. 1 is made behind the buttonhole sewing machine 1), the leg pillar 4 is provided so that it may extend upward. The upper part of the leg pillar 4 is provided with the arm 5 extended forward so that it may become parallel with the bed 3. The button hole cutting sewing machine 1 fixes and uses the bed stand 2 on the work table which has not shown in figure.

The needle bar 7 is provided in the front part of the arm 5 so that it may protrude below, and the sewing needle 6 is attached to the lower end of the needle bar 7. The needle bar 7 and the sewing needle 6 move up and down by rolling from the main shaft disposed inside the arm 5. The needle bar 7 and the sewing needle 6 move up and down alternately in the left lowered position and the right lowered position. The left lowering position and the right lowering position are positions separated by a predetermined width from side to side in a direction perpendicular to the cloth feeding direction of the transfer table 8 described later.

In the lower part of the bed 3, two loopers (not shown) are provided so as to correspond to the vertical movement positions of the needle bar 7 and the sewing needle 6. The two loopers operate in synchronism with the vertical movement of the needle bar 7 and the sewing needle 6 by transmission from the main shaft. The looper base (not shown) and the needle bar 7 supporting the two loopers rotate integrally around the vertical axis by the operation of the rotating mechanism provided inside the bed 3.

In the upper part of the bed 3, the conveyance stand 8 which supports and conveys the process cloth W (refer FIG. 5) is provided. The conveyance stand 8 can move to a left-right direction and a front-back direction in a horizontal plane by operation of the moving mechanism (not shown) provided in the lower part of the bed 3.

In the lower part of the bed 3, as shown in Fig. 5, a scalpel base 12 is provided. The scalpel base 12 is arranged on the rear side (back side of the up-and-down moving position of the needle bar 7 and the sewing needle 6) of the above-described looper base. The scalpel 13 is attached to the upper portion of the scalpel base 12 such that the scalpel 13 is substantially flush with the upper surface of the transfer table 8. As shown in Fig. 4, the scalpel 13 has a bird-shaped portion 13a and a straight portion 13b. The scalpel 13 cooperates with the first hammer 24 described later to form a "bird-eye hole" using the bird-shaped portion 13a and the straight portion 13b in the work cloth W. The scalpel 13 cooperates with the second hammer 45 to be described later to form a "closed button hole" using only the straight portion 13b in the fabric W.

On the upper part of the conveyance stand 8, a pair of left and right cloth pressing arms 15 and 16 are provided. As shown in Fig. 1 and Fig. 3, the cloth pressing arms 15, 16 have a shape that extends forwardly so as to extend upwardly from the support 8a on the upper surface of the rear part of the conveyer 8. have. Cloth pressers 15a and 16a are attached to the front ends of the cloth pressing arms 15 and 16, respectively. The cloth stoppers 15a and 16a are located on both the left and right sides of the sewing needle 6, as shown in Fig. 2, and move up and down by the operation of an air cylinder (not shown) provided in the feed table 8. The cloth pawls 15a and 16a moved downward press the fabric W placed on the feed table 8 from above.

As shown in FIG. 3 and FIG. 5, the 1st hammer 24 is provided in the position which opposes the scalpel 13 of the lower part of the conveyance stand 8 above the conveyance stand 8. As shown in FIG. The hammer support 23 is fixed to the lower end of the hammer shaft 22 provided in the front part of the arm 5. The 1st hammer 24 is attached to the hammer support stand 23 so that attachment or detachment is possible. 3 and 5, the cylindrical support 21 fixed to the lower frame 5a of the arm 5 incorporates a hammer shaft 22 and can move the hammer shaft 22 up and down. Support.

As shown in Fig. 3, a hammer drive mechanism 10 for moving the first hammer 24 up and down is provided inside the arm 5. The hammer drive mechanism 10 includes a cylinder 20 as a drive source and a link mechanism for transmitting the operation of the cylinder 20 to the hammer shaft 22.

The cylinder 20 is a double-acting air cylinder and is arranged over the entire interior of the bed base 2, the leg post 4 and the arm 3, as shown in FIG. The lower end of the cylinder 20 is connected to the lower frame 2a of the bed base 2 by the support pin 27. The cylinder 20 can be tilted back and forth with the support pin 27 as the axis.

The link mechanism for transmitting the operation of the cylinder 20 to the hammer shaft 22 includes a first link 30, a second link 32, and an intermediate link 34.

The first link 30 has an inverted L-shaped front shape as shown in FIG. The first support shaft 31 provided inside the arm 5 supports the L-shaped bent portion 30a of the first link 30. The first link 30 is rotatable about the first support shaft 31 extending in the left and right directions. The rear end 30b of the first link 30 is connected to the tip portion 20b of the piston rod 20a extending upward from the cylinder 20.

The second link 32 on the hammer shaft 22 side is a link having a linear shape as shown in FIG. The second support shaft 33 provided inside the arm 5 supports the second link 32. The second link 32 is rotatable about the second support shaft 33 extending in the left and right directions.

The front end 32a of the second link 32 extending forward is connected to the upper end of the hammer shaft 22 extending into the arm 5. Blocks (not shown) that are rotatably supported by the support pins 38 are arranged at the connecting portion between the second link 32 and the hammer shaft 22. The block supported by the support pin 38 is before and after the end 32a of the second link 32 rotating about the second support shaft 33 and the upper end of the hammer shaft 22 moving up and down. Allow relative movement in the direction.

The rear end 32b of the second link 32 is connected to the front end 30c of the first link 30 via the intermediate link 34. The connecting pin 35 connects the end link 30c of the first link 30 with the intermediate link 34. The connecting pin 36 connects the end link 32b of the second link 32 with the intermediate link 34. The connecting pins 35 and 36 extend in parallel with the first support shaft 31 and the second support shaft 33. As shown in Fig. 3, the front portion of the second link 32 is applied upward by the spring 43. The spring 43 is caught by the engaging pin 41 provided on one surface of the first half of the second link 32 and the engaging pin 42 provided on the upper frame 5b of the arm 5.

As shown in Fig. 3, on the rear side of the first hammer 24, a hammer moving mechanism 47 for moving the second hammer 45 and the second hammer 45 in the vertical direction and the front-rear direction is disposed. have. The structure of the 2nd hammer 45 and the hammer movement mechanism 47 is demonstrated below.

The hammer movement mechanism 47 includes an air cylinder 49 (second drive mechanism) for forward and backward movement and an air cylinder 53 (first drive mechanism) for vertical movement. As shown in FIG. 3 and FIG. 5, the hammer support 23 is attached with an L-shaped connecting support 48. The air cylinder 49 for back and forth movement is being fixed to the upper end of the connection support 48 extended upward. The air cylinder 49 for front and rear movement is provided with the piston rod 49a which protrudes to the rear direction, as shown to FIG. 5 and FIG. Above and below the piston rod 49a, guide shafts 49b and 49b parallel to the piston rod 49a are provided. The first connecting member 50 is fixed to the tip ends of the piston rod 49a and the guide shafts 49b and 49b. The piston rod 49a is advanced or retracted by the operation of the air cylinder 49 for forward and backward movement. Guide shafts 49b and 49b guide the first connecting member 50. The first connecting member 50 moves in the front-rear direction as the piston rod 49a moves forward and backward. Advancement of the piston rod 49a shows the operation which the piston rod 49a protrudes from the back and forth movement air cylinder 49, and shows that the piston rod 49a moves backward in FIG. .

The L-shaped connecting support 51 is fixed to the first connecting member 50 by a plurality of fixing bolts 52. The up-and-down moving air cylinder 53 is fixed to the lower end of the connection support body 51 extended forward. The up-and-down movement air cylinder 53 is provided with the piston rod 53a which protrudes downwards, as shown to FIG. 6 and FIG. Before and after the piston rod 53a, the guide shafts 53b and 53b which are parallel to the piston rod 53a are provided. The second connecting member 54 is fixed to the front ends of the piston rod 53a and the guide shafts 53b and 53b. The piston rod 53a is raised or lowered by the operation of the up-down moving air cylinder 53. The guide shafts 53b and 53b guide the second connecting member 54. The second connecting member 54 moves in the vertical direction in accordance with the rise (retraction) and the fall (advanced) of the piston rod 53a.

On the lower surface of the second connecting member 54, a flat hammer support 45a is fixed with a plurality of fixing bolts 55. As shown in FIG. The second hammer 45 is formed at the end of the hammer support 45a extending forward. The 2nd hammer 45 is a small hammer corresponding only to a part of straight part 13b of the scalpel 13, as shown by the dashed-dotted line in FIG.

4, the planar shape of the 1st hammer 24 is also shown with the dashed-dotted line. The first hammer 24 is larger than the second hammer 45. The first hammer 24 has a shape including a bird-eye portion 13a and a straight portion 13b of the scalpel 13.

The operation of the buttonhole sewing machine 1 will be described.

The cylinder 20 of the hammer drive mechanism 10 is in the forward position shown in FIG. 3 as usual. In this case, the first link 30 rotates in the counterclockwise direction and the second link 32 rotates in the clockwise direction as the piston rod 20a moves forward. The second link 32 rotating in the clockwise direction pulls up the hammer shaft 22 connected to the front end of the second link 32 upward. The first hammer 24 fixed to the lower end of the hammer shaft 22 rises and is located away from the processing cloth W on the feed table 8 as shown by the solid line in FIG. The intermediate spring 43 of the second link 32 assists the pulling of the hammer shaft 22 with the spring force.

The piston rod 49a of the air cylinder 49 for the forward and backward movement of the hammer movement mechanism 47 is normally in a forward position, and moves the first connecting member 50 fixed to the distal end of the piston rod 49a backward. Let's do it. The piston rod 53a of the up-down movement air cylinder 53 is normally in a raised position, and moves the 2nd connection member 54 fixed to the front-end | tip part of the piston rod 53a upwards. The 2nd hammer 45 fixed to the 2nd connection member 54 moves to back upward, and becomes the standby position shown by the solid line in FIG. The standby position of the 2nd hammer 45 is located behind the 1st hammer 24 (on the support part 8a side of the feeder 8 rather than the 1st hammer 24 in the horizontal direction, and on the feeder 8). Position away from the processing cloth (W).

When forming the "bird-eye hole" in the processing cloth W, the cylinder 20 is driven backward. In this case, the first link 30 rotates clockwise by the retraction of the piston rod 20a, and the second link 32 rotates counterclockwise. The second link 32 rotating in the counterclockwise direction pushes the hammer shaft 22 connected to the front end of the second link 32 downward. The 1st hammer 24 fixed to the lower end of the hammer shaft 22 descends, and presses the workpiece | work cloth W arrange | positioned at the feed table 8 to the scalpel 13. As described above, the first hammer 24 has a planar shape including the bird eye portion 13a and the straight portion 13b of the scalpel 13. The scalpel 13 and the first hammer 24 form a "bird-eye hole" in the fabric W. When forming a "closed buttonhole" in the processing cloth W, the buttonhole cutting sewing machine 1 drives the piston rod 53a of the up-down moving air cylinder 53 downward. As the piston rod 53a descends, the second connecting member 54 descends. When the second connecting member 54 descends, the second hammer 45 fixed to the second connecting member 54 moves to an intermediate position. As shown in FIG. 6, the intermediate position is a position where the upper surface of the second hammer 45 is approximately the same height as the lower surface of the first hammer 24 on the rear side of the first hammer 24. As shown in FIG. The intermediate position may be a position where the upper surface of the second hammer 45 is lower than the lower surface of the first hammer 24.

Thereafter, the buttonhole tightening sewing machine 1 drives the piston rod 49a of the air cylinder 49 for forward and backward movement backward. The first connecting member 50 and the connecting support 51 move forward by the retraction of the piston rod 49a. When the connection support body 51 moves forward, the up-down movement air cylinder 53 moves forward. The 2nd hammer 45 moves forward from the above-mentioned intermediate position with the 2nd connection member 54 by the movement of the air cylinder 53 for up-down movement. As shown by the solid line in FIG. 7, the second hammer 45 is in an operating position superimposed on the lower surface of the first hammer.

When the cylinder 20 is retracted and driven in a state where the second hammer 45 is in the operating position, a "closed button hole" can be formed. By the retraction drive of the cylinder 20, the 1st hammer 24 descends as mentioned above. In this case, as shown by the dashed-dotted line in FIG. 7, the 2nd hammer 45 which overlaps with the lower surface of the 1st hammer 24 also descend | falls simultaneously. The descending second hammer 45 presses the working cloth W against the scalpel 13. As described above, the second hammer 45 has a planar shape corresponding to only a part of the straight portion 13b of the scalpel 13. The scalpel 13 and the second hammer 45 form a straight "closed buttonhole" corresponding to the straight portion 13b of the scalpel 13 in the work cloth W. FIG.

In the button-hole sewing machine 1 of the present invention, the second hammer 45 has the first hammer 24 from the standby position set on the opposite side of the needle bar 7 with the first hammer 24 therebetween. It moves to the lower operation position by the operation of the hammer moving mechanism 47. The movement path of the second hammer 45 does not interfere with the cloth presses 15a and 16a that press the working cloth W on the feed table 8 on both the left and right sides of the needle bar 7. The buttonhole knitting machine 1 of the present invention does not need to move the feed table 8 back and forth when forming the "closed buttonhole" using the second hammer 45, and the holemaking work efficiency is improved. This is improved.

The second hammer 45 descends from the standby position to the intermediate position by the operation of the up-down moving air cylinder 53, and then moves forward from the intermediate position to the operating position by the operation of the back and forth moving air cylinder 49. The movement path of the second hammer 45 does not interfere with the first hammer 24 located at the front lower portion of the second hammer 45. The second hammer 45 moves quickly and reliably from the standby position to the operating position.

The up-down movement air cylinder 53 is fixed to the front-end | tip part of the piston rod 49a of the front-back movement air cylinder 49. As shown in FIG. The 2nd hammer 45 is being fixed to the front-end | tip of the piston rod 53a of the air cylinder 53 for vertical movement. The hammer movement mechanism 47 including the forward and backward movement air cylinder 49 and the up and down movement air cylinder 53 can be simply configured, and assembly is easy.

The modified form which partially changed embodiment described above is demonstrated.

1) The vertical movement air cylinder 53 which moves the 2nd hammer 45 up and down may be comprised by other actuators, such as a solenoid for vertical movement. Similarly, the air cylinder 49 for forward and backward movement which moves the 2nd hammer 45 back and forth may also be comprised by other actuators, such as a solenoid for forward and backward movements.

2) The structure of the hammer drive mechanism 10 is not limited to the structure shown in FIG. For example, the hammer drive mechanism may be configured to include a pulse motor that directly drives the hammer shaft 22.

3) In the above-mentioned embodiment, the up-down movement air cylinder 53 is being fixed to the piston rod 49a of the back-and-forth movement air cylinder 49 via the connection support body 51. The modified form may fix the up-down movement air cylinder 53 directly to the front-end | tip part of the piston rod 49a or the 1st connection member 50 attached to the front-end | tip part.

4) The hammer movement mechanism 47 of the above-mentioned embodiment is provided with the air cylinder 53 for up-and-down movement, and the air cylinder 49 for forward and backward movement. The modified form may omit the up-and-down movement air cylinder 53, and may comprise the hammer movement mechanism 47 only with the back and forth movement air cylinder 49. As shown in FIG. The second hammer 45 is brought into the operating position by the linear movement in the forward direction, and the standby position by the linear movement in the rear direction.

5) The modified form may include a first hammer having a shape that does not use the bird-shaped portion 13a. In this case, a "closed buttonhole" having a different length can be formed by the first hammer and the second hammer.

6) In the modified form, the mounting position of the scalpel 13 may be changed to form a "closed button hole" with a first hammer and a "bird-eye hole" with a second hammer.

As apparent from the above detailed description, the buttonhole sewing machine of the present invention includes a second hammer used for forming a buttonhole different from the buttonhole formed by the first hammer. The second hammer moves by the operation of the hammer moving mechanism between the standby position of the rear upper part of the first hammer and the operating position overlapping the lower surface of the first hammer. The movement path of the 2nd hammer is a combination of the movement of the up-down direction and the front-back movement, and does not interfere with the cloth stopper which presses a process cloth on a conveyance stand. When forming the button hole with the second hammer in the operating position, it is not necessary to move the feed table back and forth, so that the hole cutting process can be reduced and the work efficiency can be improved.

1 is a side view of a buttonhole sewing machine of the present invention.

Figure 2 is a front view of a buttonhole sewing machine of the present invention.

Figure 3 is a side view showing the internal structure of the buttonhole sewing machine of the present invention.

4 is a plan view of the scalpel and the first and second hammers.

Fig. 5 is an enlarged side view of an essential part showing a state where the second hammer is in the standby position;

Fig. 6 is an enlarged side view of an essential part showing a state in which the second hammer is in an intermediate position;

Fig. 7 is an enlarged side view of an essential part showing a state in which the second hammer is in the operating position;

<Explanation of symbols for the main parts of the drawings>

1: buttonhole sewing machine

10: hammer drive mechanism

13: scalpel

20: cylinder

20a, 49a: piston rod

22: hammer shaft

24: first hammer

32: link

31, 33: support shaft

41: coupling pin

45: second hammer

49: air cylinder for forward and backward movement

51: connecting support

52: fixing bolt

53: air cylinder for vertical movement

Claims (4)

The feeder supports a cloth press for pressing the fabric to the feeder, and a scalpel disposed below the fabric to be pressed by the cloth press, and disposed behind the sewing needle and facing the upper portion of the scalpel with the fabric cloth interposed therebetween. In the button-hole sewing machine provided with a 1st hammer, and the said 1st hammer descends and presses the said processing cloth to the said scalpel, and forms a buttonhole in a press part, A second hammer having a shape different from that of the first hammer, And a hammer movement mechanism for moving said second hammer between a standby position behind said first hammer and an operating position below said first hammer in a horizontal direction. The hammer movement mechanism according to claim 1, wherein the hammer moving mechanism moves the second hammer up and down between an intermediate position where the upper surface of the second hammer is lower than or equal to the lower surface of the first hammer and the standby position. And a first drive mechanism and a second drive mechanism for moving the second hammer back and forth between the intermediate position and the operating position. The method of claim 2, wherein the first drive mechanism is composed of an air cylinder for vertical movement, The said 2nd drive mechanism is comprised from the air cylinder for back and front movement, The vertical movement air cylinder is fixed to the front end portion of the piston rod of the front and rear movement air cylinder, button hole sewing machine, characterized in that. The button hole sewing machine according to claim 3, wherein the second hammer is fixed to a distal end portion of a piston rod of the vertical cylinder.

Images