KR20080039283A - Button holing sewing machine - Google Patents

Abstract

A sewing machine for holding a button is provided to insert a thread into a needle bar smoothly without using a separate threading machine, thereby efficiently performing a thread-threading operation. A sewing machine comprises a needle bar(12) having an upper thread guider therethrough, an up-down moving unit(20) for upwardly or downwardly moving the needle bar, a needle-shaking unit(30) for shaking the needle bar, a looper(40), a turning unit(60) for turning the needle bar and the looper, and a moving unit for moving processed cloth. The needle bar has an inclined opening for jetting air to the upper thread guider. An air nozzle for an upper thread is disposed at a side of the needle bar. A controller controls the up-down moving unit, the needle-shaking unit, and the turning unit to fix the opening of the needle bar to an outlet of the nozzle.

Description

Buttonhole sewing machine {BUTTON HOLING SEWING MACHINE}

The present invention relates to a buttonhole sewing machine for performing a thread sewing operation for the upper thread or the lower thread.

Conventional buttonhole sewing machines have a needle bar hollowed out from an upper end thereof to a withdrawal hole near the lower end to guide the thread. It was.

The conventional buttonhole sewing machine includes a hollow pipe-shaped looper drive shaft disposed at the center of the looper base supporting the looper and the spreader and a spreader drive shaft inserted inside the looper drive shaft. These drive shafts can move up and down with respect to the looper base, and each of the drive shafts is configured to impart a predetermined motion to the looper and the spreader by reciprocating up and down. The looper drive shaft is formed in a hollow pipe shape over the entire length thereof to guide the thread, and the lower thread is inserted from the lower end portion to the upper end portion inside the hollow to guide the lower thread through the looper and the spreader (eg, , Patent Document 1).

By the way, when setting a thread to a predetermined thread path before starting sewing, it is necessary to insert each thread into the said needle bar and a looper drive shaft. However, since the inside of the needle bar or the looper drive shaft is narrow, it is difficult to directly thread the thread through the thread, which makes the threading work very complicated. For this reason, the thread sewing mechanism as shown in FIG. 11 has been used.

The thread sewing mechanism has a hook portion at one end, and the other end is a ring-shaped handle. The thread is tied at one end to a needle bar or a looper drive shaft, and the thread sewing mechanism is pulled from the end thereof. It could be threaded.

[Patent Document 1] Japanese Patent Laid-Open No. 2001-170385

As described above, the conventional buttonhole sewing machine has a problem that it is difficult to fit the upper thread or the lower thread to the needle bar or the looper drive shaft unless the thread sewing mechanism is used.

In addition, the thread sewing mechanism is often made of metal, and when inserted into the needle bar or the looper drive shaft, there is a fear of causing scratches therein.

In addition, a method of inserting a thread by applying an airgun to the inlet of the needle guide of the needle bar or the looper drive shaft and injecting air therein is also considered. As a result, it is expected that the air gun will eventually interfere, making it difficult to put the thread into the thread guide.

An object of the present invention is to easily and smoothly perform a thread sewing operation of the upper thread or the lower thread.

The invention described in claim 1,

A needle bar 12 having a needle thread 12 having a hole into which the upper thread is inserted is formed, and having an upper thread guide hole 12a for guiding the upper thread by communicating from the upper end to the lower end, and the needle bar up and down. Shanghai swing mechanism 20 connected to the needle bar to move, needle swing mechanism 30 for swinging the needle bar in a predetermined needle swing direction, and is installed on the lower side of the sewing machine sewing surface, swinging to bind the lower thread to the upper thread The looper and the spreader are supported by the looper base, and the looper mechanism 40 which swings the looper or the spreader and the needle bar and the looper base to pivot the needle bar and the looper base about the same axis. A buttonhole sewing machine having a turning mechanism arranged in a line, and forming a needle stitch around the buttonhole of the fabric,

A needle bar opening 12b which communicates with the upper thread guide hole from the outer side of the needle bar, and is inclined so that air flowing from the outside flows from the upper side inside the upper thread guide hole downward;

An upper nozzle air nozzle (83) having a discharge port for discharging air to the needle bar opening portion, and arranged on a side of a shanghai east path of the needle bar;

The upper thread sewing control means for controlling the shank moving mechanism, the needle swing mechanism and the turning mechanism, and for adjusting the position of the needle bar at a predetermined position to allow air to flow from the discharge port of the upper thread air nozzle to the needle bar opening. We adopt constitution to make.

The invention described in claim 2 has the same configuration as the invention described in claim 1,

An upper thread retraction mechanism for moving the upper thread air nozzle forward and backward between an operating position where the discharge port is connected to the needle bar opening of the needle bar positioned at the predetermined position and a standby position where the discharge port is isolated from the operating position. Equipped,

The upper thread sewing control means adopts a configuration for controlling the upper thread retracting mechanism to position the needle bar at the predetermined position and to move the upper thread air nozzle from the standby position to the operating position.

The invention described in claim 3 has the same configuration as the invention described in claim 1 or 2,

The upper thread sewing switch for outputting the upper thread sewing command signal by an input operation,

The upper thread sewing control means adopts a configuration for controlling the drive source of the shank moving mechanism, the needle swing mechanism and the turning mechanism so that the needle bar is in the predetermined stop position in response to the upper thread sewing command signal.

The invention described in claim 4,

A needle bar 12 having a needle 11 having a hole into which an upper thread is inserted, held at a lower end thereof, a shank moving mechanism 20 connected to the needle bar to move the needle bar up and down, and the needle bar in a predetermined needle swing direction Needle swing mechanism (30) for oscillating with a shaft, and drive shafts (45, 46) formed with hollow lower thread guide holes for guiding the lower thread from the lower end to the upper end, and are installed below the sewing surface of the sewing machine, and the lower thread is tied to the upper thread. A looper mechanism for supporting the looper and the spreader, which swings so as to support the looper base, and swinging the looper or the spreader by moving the drive shaft up and down, and the needle bar and pivoting the needle bar and the looper base about the same axis. A turning mechanism arranged in association with the looper base, and each needle forms a needle stitch around the buttonhole of the fabric. Is a driving buttonhole sewing machine,

A drive shaft opening communicating with the lower thread guide hole from the outer side of the drive shaft, the drive shaft opening being inclined so as to communicate with the lower thread guide hole from the outer side and inflowing from the outside to flow upward from below the inside of the lower thread guide hole;

An air nozzle for a lower thread having a discharge port for discharging air to the opening of the drive shaft, and arranged at a side of the drive shaft;

And a bobbin threading control means for controlling the looper mechanism and the swing mechanism and for adjusting the position of the drive shaft to a predetermined position where air can flow from the discharge port of the lower thread air nozzle to the drive shaft opening. .

The invention described in claim 5 has the same configuration as the invention described in claim 4,

A lower thread retraction mechanism for moving the lower thread air nozzle back and forth between an operating position at which the discharge port is connected to a drive shaft opening of the drive shaft located at the predetermined position and a standby position at which the discharge port is isolated from the operating position; Equipped,

The bobbin thread control means adopts a configuration for controlling the bobbin thread retraction mechanism to position the drive shaft at the predetermined position and to move the bobbin air nozzle from the standby position to the operating position.

The invention according to claim 6 has the same configuration as the invention according to claim 4 or 5,

A bobbin thread switch for outputting a bobbin thread command signal by an input operation;

The lower thread sewing control means adopts a configuration for receiving the lower thread sewing command signal and controlling the drive source of the looper mechanism and the turning mechanism so that the needle bar is at the predetermined stop position.

In the invention according to claim 1, during sewing, air flows from the discharge port of the upper thread air nozzle to the needle bar opening portion by means of the upper thread sewing control means, by means of upper thread sewing control means. Since it is arrange | positioned at the predetermined position which can be made, air can be injected from the upper thread air nozzle with respect to the needle bar arrange | positioned at the said predetermined position.

When air is injected from the needle bar opening, the air flows from the upper side of the upper thread guide portion to the lower side according to the inclination of the needle bar opening, so that the inside of the section upstream than the needle bar opening of the upper thread guide portion has a negative pressure. The result is a flow of air over the entire length of the upper thread guide. Therefore, the tip of the upper thread can be pulled out from the upper end of the needle bar to the upper thread guide and drawn out to the lower end by piggybacking on the flow of air.

Thus, the upper thread can be inserted into the needle bar without using the thread sewing mechanism. Therefore, it is possible to prevent scratches on the upper thread guide portion.

In addition, there is no need to touch the air gun at the inlet of the upper thread guide part, so there is no obstacle to the insertion of the upper thread, so that the upper thread inserting operation of the upper thread guide part can be easily and smoothly performed.

On the other hand, the state in which air can flow from the discharge port of the upper threaded air nozzle to the needle bar opening is not limited to the state where the discharge port of the upper threaded air nozzle is in close contact with the needle bar opening. If air is injected into the needle bar opening enough to occur, a gap may be formed between the nozzle discharge port and the needle bar opening.

In the invention according to claim 2, the needle bar is arranged at a predetermined position by the upper thread sewing control means, and the upper thread discharge port of the nozzle moves to the operation position, so that air can be injected from the upper thread discharge port to the needle bar opening.

On the other hand, since the upper threaded air nozzle can be moved to the standby position away from the needle bar, it is possible to avoid the case of being disturbed by the needle bar for sewing operation, especially by moving to the standby position during sewing.

In the invention according to claim 3, since the needle bar can be adjusted to a predetermined position by an input operation of the needle threading switch, the operation of inserting the upper thread into the needle thread guide of the needle bar can be performed smoothly arbitrarily.

In the invention as set forth in claim 4, during sewing, air is circulated from the discharge port of the lower thread air nozzle to the drive shaft opening by means of the lower thread sewing control means. Since it is arrange | positioned at the position of, the air can be injected from the lower thread air nozzle with respect to the drive shaft arrange | positioned at the said predetermined position.

When air is injected from the drive shaft opening, the air flows upward from the lower thread guide hole according to the inclination of the drive shaft opening, so that the inside of the section upstream of the drive shaft opening in the lower thread guide hole also becomes negative pressure. As a result, a flow of air is produced over the entire length of the lower thread guide hole. Therefore, the tip of the lower thread can be pulled out from the lower end of the drive shaft to the lower thread guide hole and drawn out to the upper end by piggybacking on the flow of air.

Thereby, the lower thread can be inserted in the drive shaft without using the thread sewing mechanism. Therefore, it is possible to prevent the occurrence of scratches in the lower thread guide hole.

In addition, since there is no need to touch the air gun at the inlet of the lower thread guide hole, there is no interference with the insertion of the lower thread, so that the operation of inserting the lower thread into the lower thread guide hole can be easily and smoothly performed.

On the other hand, the state in which air can flow from the discharge port of the lower thread air nozzle to the drive shaft opening is not limited to the state where the discharge port of the lower thread air nozzle is in close contact with the opening of the drive shaft. If air is injected into the drive shaft opening to a sufficient extent, a gap may be formed between the nozzle discharge port and the drive shaft opening.

In the invention according to claim 5, since the drive shaft is disposed at a predetermined position by the bobbin weaving control means and the discharge port for the lower thread of the nozzle moves to the operating position, air can be injected from the discharge port for the lower thread to the drive shaft opening.

On the other hand, since the lower thread air nozzle can be moved to the standby position away from the drive shaft, it is possible to avoid the case where the sewing shaft is disturbed by moving to the standby position, especially during sewing.

In the invention according to claim 6, since the drive shaft can be adjusted to a predetermined position by the input operation of the bobbin threading switch, the operation of inserting the bobbin thread into the bobbin guide hole of the drive shaft can be performed smoothly arbitrarily.

(Overall Configuration of Embodiments)

A buttonhole sewing machine 10 which is an embodiment of the present invention will be described based on FIGS. 1 to 10. 1 is a side cross-sectional view of the buttonhole sewing machine 10, FIG. 2 is an enlarged cross-sectional view showing the upper periphery of the needle bar 12, Figure 3 is an enlarged cross-sectional view seen from above the upper periphery of the needle bar 12.

As shown in Fig. 1, the buttonhole sewing machine 10 is located at the bottom of the sewing machine as a whole, and has a bed portion 2a that forms a substantially rectangular box shape, and is vertically provided at one end of the bed portion 2a. A sewing machine frame (2) having a body portion (2b) and an arm portion (2c) is formed extending from the longitudinal body portion (2b) in the same direction as the bed portion (2a). In addition, in the following description, the direction in which the vertical body part 2b is standing up is orthogonal to a Z-axis direction and a Z-axis direction, and the longitudinal direction of the bed part 2a and the arm part 2c is Y-axis direction, Y The direction orthogonal to both an axial direction and a Z-axis direction is called an X-axis direction.

The buttonhole sewing machine 10 is a needle bar 12 for holding the sewing needle 11, the upper thread (U) is fitted, the shank copper mechanism 20 for moving the needle bar 12 up and down, needle bar 12 Swing mechanism 30 for swinging the needle, looper mechanism 40 for forming needle stitches, swing mechanism 60 for turning the needle bar 12 and the looper base 45 of the looper mechanism 40, and cloth A lifting mechanism (not shown) which raises and maintains the fabric by the lifting table 71 and moves in the X and Y-axis directions, and an upper for sending air into the upper thread guide portion 12a of the needle bar 12 described later. The practical air discharge device 80, the lower thread air discharge device 90 for sending air to the inside of the lower thread guide hole 45a of the spreader drive shaft 45 of the looper mechanism 40 described later, and the operation of the respective configurations. Operation control means 100 for controlling the.

(Needle)

1 and 2, the needle bar 12 is supported by a metal 14 held in a thin disk-shaped leaf spring 13 installed at the upper end of the arm portion 2c. The leaf spring 13 is disc shaped and its outer circumference is held by the arm portion 2c. The metal 14 is arrange | positioned at the center position of the leaf spring 13. The metal 14 is cylindrical in shape, and is held by the leaf spring 13 in a state in which the center line thereof faces in the Z-axis direction when no external force is applied.

The needle bar 12 has a round rod shape and is inserted into the metal 14. The needle bar 12 is supported by the metal 14 so that the needle bar 12 can slide along its longitudinal direction and rotate about an axis along the longitudinal direction. In addition, since the metal 14 is held at the center of the leaf spring 13 as described above, the needle bar 12 inserted into the metal 14 is in a range allowed for the bending of the leaf spring 13, The lower end portion can be tilted in any direction perpendicular to the Z-axis direction with respect to the position of the metal 14.

Further, the needle bar 12 is provided with an upper thread guide portion (upper thread guide hole; 12a) which communicates from the upper end to the lower end and maintains the sewing needle 11 at the lower end thereof, and is formed hollow inside. In the upper thread guide portion 12a, the upper end surface of the needle bar 12 becomes the inlet of the upper thread U, and the outer side surface near the lower end of the needle bar 12 is the outlet. And a thread tension adjusting device 15 for providing tension to the thread is provided near the outlet of the upper thread guide portion 12a.

That is, the upper thread U is guided through the upper thread guide 12a from the upper end of the needle bar 12 to the vicinity of the lower end, and is inserted into the hole (not shown) of the sewing needle 11 through the thread tension adjusting device 15. It is supposed to be.

In addition, the needle bar 12 is formed with a needle bar opening 12b penetrating from the outer circumferential surface to the upper thread guide part 12a at its intermediate position (see Fig. 6). The needle bar opening 12b injects air from the upper thread air discharging device 80 to be described later to generate an air flow in the direction from the upper end to the lower end in the upper thread guide 12a, and from the upper end of the needle bar 12. It is a hole for sending the upper thread U to the lower end, and is formed to be inclined downward from the orthogonal direction with respect to the upper thread guide part 12a. When air is injected from the needle bar opening 12b by this inclination, air flows downward by air in the section above the needle bar opening 12b inside the upper thread guide part 12a, and as a result, In the section above the needle bar opening 12b, a negative pressure is generated, and as the outside air flows in from the upper end of the upper thread guide portion 12a, an air flow downward is generated over the entire length of the upper thread guide portion 12a.

In addition, the inclination angle θ of the needle bar opening 12b with respect to the upper thread guide portion 12a is preferably about 30 °, and may be changed within the range in which the above action can occur.

Moreover, since the needle bar 12 oscillates laterally with the metal 14 as a support point, in order to easily match the position of the needle bar opening part 12b and the upper threaded air discharge apparatus 80, in the range which is possible. It is preferable to form the needle bar opening 12b in the vicinity of the metal 14 on the needle bar upper end side with less fluctuation of displacement.

(Up and down moving mechanism)

The shank moving mechanism 20 has a well-known structure, and as shown in Figs. 1 to 3, an upper shaft 21 driven by a timing belt not shown by a sewing machine motor (sewing machine drive source; 3), which is a servo motor, A rod having one end connected to the needle bar drive shaft 24 through a eccentric cam 25 and a needle bar drive shaft 24 through which an increase in speed is transmitted from the upper shaft 21 by large and small gear lines 22 and 23. 26, a shanghai-dong arm 27 having one end connected to the other end of the rod 26, a fork end member 28 provided at the other end of the shanghai-dong arm 27, and a fork end member ( 28 and a ring 29 connecting the needle bar 12.

In addition, the sewing machine motor 3 is provided with an encoder (not shown), so that the rotational position of the sewing machine motor 3 can be detected.

Both the upper shaft 21 and the needle bar drive shaft 24 are installed along the X-axis direction and are rotatably supported inside the sewing machine frame 2. The rotation force is transmitted from the upper shaft 21 to the needle bar drive shaft 24 by the gear lines 22 and 23 at twice the rotation speed.

The shanghai-dong arm 27 is axially supported in the sewing machine frame 2 by the support shaft along the X-axis direction in the longitudinal intermediate position. As the rod 26 and the eccentric cam 25 rotate the rotational movement of the needle bar drive shaft 24 into the reciprocating motion and are transmitted to one end of the shanghai-dong arm 27, both ends thereof approximately in the Z-axis direction. It is possible to swing accordingly.

The other end of the shandong copper arm 27 is connected to the needle bar 12 by the fork end member 28 and the ring 29.

The fork end member 28 moves forward and backward along the extension forming direction (approximately Y-axis direction) of the other end of the shandong east arm 27 with respect to the shandong east arm 27, and the other end of the shandong east arm 27. It is supported so that rotation based on the extension formation direction of the edge part is possible.

The ring 29 has a straight movement along the direction orthogonal to the extending forming direction (approximately the Y-axis direction) of the other end of the shank east arm 27 with respect to the fork end member 28, and the other end of the arm 27. It is supported so that rotation based on the direction orthogonal to an extension formation direction is possible.

In addition, the ring 29 is connected to the needle bar 12 in a state of being inserted into two collars 29a fixed to the needle bar 12 while the needle bar 12 is inserted therein, and the needle bar with respect to the ring 29. (12) is able to rotate about an axis.

With this configuration, even if the needle bar 12 is in a tilted state in any direction allowed by the metal 14, and even if the needle bar 12 is rotated around its longitudinal direction, the shanghai arm 27 It is possible to impart a reciprocating up and down movement force.

(Needle swing mechanism)

The needle swing mechanism 30 has a well-known structure, and as shown in FIGS. 1 to 3, a rod 32 swinging in contact with the outer circumference cam 31 provided on the upper shaft 21 and the outer circumference of the outer circumference cam 31. And a link 33 connected to the swing end of the rod 32 to which the reciprocating motion is applied, an L type arm 34 connected to the link 33, and a rotational type of the L type arm 34. A link 35 to which the up and down reciprocating motion is given, a slider 36 to which the up and down reciprocating motion is transmitted from the link 35, and a slide guide shaft allowing the slider 36 to reciprocate only along the Z axis direction. 37 and a swinging table 38 that moves in the X-axis direction along the height. The needle swing mechanism 30 swings the needle bar 12 in a predetermined needle swing direction in association with the upper shaft 21.

The outer cam 31 provides the rod 32 with a reciprocating rocking motion of one stroke along the Y-axis direction per one rotation of the upper shaft 21.

The rod 32 transmits the reciprocating motion along the Y-axis direction to the L-shaped arm 34 through the link 33, and the L-shaped arm 34 converts the reciprocating motion direction to the Z-axis direction and links 35 It passes to the slider 36 through.

The slider 36 supports the swing table 38 to be able to rotate around the Z axis, and the swing table 38 is also moved up and down as the slider 36 moves up and down.

The swinging table 38 supports the needle bar 12 to be moved up and down in a state where the lower end of the needle bar 12 is inserted, and guide grooves inclined between the Z-axis direction and the X-axis direction on both outer sides thereof. Is formed. Then, the swinging table 38 is fitted by a concave body (not shown) fitted to the guide groove from both sides thereof. When the swinging table 38 moves in the up and down direction, the swinging table 38 moves obliquely along the guide groove. ) Causes displacement in the X-axis direction, causing the needle to swing.

As described above, since the needle bar drive shaft 24 rotates at twice the speed of the upper shaft 21, the needle bar 12 moves up and down twice when the swing table 38 reciprocates once in the X-axis direction. That is, the needle bar 12, by the cooperation of the shank moving mechanism 20 and the needle swing mechanism 30, falls even if the needle swings in any direction.

In addition, since the convex-shaped body which is not shown in figure is supported by the revolving table 61 of the revolving mechanism 60 mentioned later, at the time of turning of the needle bar 12, the needle swing direction is also revolving simultaneously.

The needle swing mechanism may be provided with a unique drive source such as a stepping motor to swing in the needle swing direction.

(Looper mechanism)

The looper mechanism 40 has a well-known structure, and is installed on the lower side of the cloth lifter 71 that is the sewing surface of the sewing machine, and the looper 49 and 50 that swings to bind the lower thread D to the upper thread U, and The spreaders 51 and 52 are supported on the looper base 47, and the loopers 49 and 50 or the spreaders 51 and 52 are oscillated in conjunction with the sewing machine motor 3 as the sewing machine driving source.

Specifically, as shown in FIGS. 1 and 4, the lower shaft 41 rotated by the sewing machine motor 3, the groove cam 42 provided on the lower shaft 41, and the groove cam 42 are engaged with each other. Spreader swing arm 43 and looper swing arm 44, spreader drive shaft 45 serving as a drive shaft moved up and down by spreader swing arm 43, and drive shaft moved up and down by looper swing arm 44 The looper drive shaft 46, the looper base 47 supported by the sewing machine frame 2 so that rotation is possible in the state which arrange | positioned these drive shafts 45 and 46 in the center position, and the lower thread to the upper thread U ( D) The left looper 49 and the left spreader 51 which bundle a double round bar, and the right looper 50 which performs a single yarn round bar by the upper thread U, are tied together. And the right spreader 52 and the respective loopers 49 and 50 and the vertically below the needle plate 48 attached to the upper end of the looper base 47. The attachment table 53 which supports the spreaders 51 and 52, the thread take-up spring 54 which gives tension to the lower thread D, and the thread guide members 55 and 56 are provided.

The sewing machine motor 3, the lower shaft 41, the groove cam 42, the spreader swing arm 43 and the looper swing arm 44 constitute a shaft drive mechanism.

The groove cam 42 has cam grooves formed on both surfaces thereof, and each of them is engaged with the spreader swinging arm 43 and the looper swinging arm 44 so as to swing at predetermined timings.

The spreader rocking arm 43 is axially supported by a support shaft in the longitudinal intermediate position in the X-axis direction, one end thereof is engaged with the groove cam 42, and the other end thereof is the spreader drive shaft 45. Is engaged at the bottom of the That is, the spreader rocking arm 43 oscillates at a predetermined timing determined according to the cam groove shape of the groove cam 42 to move the spreader drive shaft 45 up and down.

The looper rocking arm 44 is axially supported by a support shaft in the longitudinal intermediate position in the X-axis direction, one end of which is engaged with the groove cam 42, and the other end of the looper swinging arm 44 at the lower end of the looper drive shaft 46. It is stuck. That is, the looper swinging arm 44 swings at a predetermined timing determined according to the cam groove shape of the groove cam 42 to move the looper drive shaft 46 up and down.

The looper drive shaft 46 is cylindrical in shape, and the spreader drive shaft 45 can be inserted therein. In addition, the looper drive shaft 46 is connected to the attachment table 53 through a link at the upper end thereof, and swings the attachment table 53 by moving up and down, so that each looper 49 and 50 and each spreader 51 are rotated. And needle stitch forming operation by (52).

The spreader drive shaft 45 has a cylindrical shape and has a lower thread guide hole 45a penetrating from the lower end to the upper end, and has a function of guiding the lower thread D from the lower end to the upper end. In addition, the spreader drive shaft 45 is connected to a cam (not shown) through a link at its upper end, and swings the spreaders 51 and 52 through the cam to move up and down so as to widen the seal loop.

Further, the spreader drive shaft 45 is formed with a drive shaft opening 45b penetrating from the outer circumferential surface to the lower thread guide hole 45a near the lower end portion thereof (see FIG. 7). The drive shaft opening 45b injects air from the lower thread air discharging device 90 to be described later to generate airflow in the direction from the lower end to the upper end in the lower thread guide hole 45a, from the lower end of the spreader drive shaft 45. As a hole for sending the lower thread D to the upper end, it is formed to be inclined upwardly from the direction perpendicular to the lower thread guide hole 45a. When air is injected from the drive shaft opening part 45b by such inclination, the airflow upwards is produced | generated by air in the section upper than the drive shaft opening part 45b in the lower thread guide hole 45a, and as a result, As the negative pressure is generated in a section below the drive shaft opening 45b and the outside air flows in from the lower end of the lower thread guide hole 45a, an air flow upward is generated in the entire length of the lower thread guide hole 45a.

In addition, the inclination angle θ of the drive shaft opening 45b with respect to the lower thread guide hole 45a is preferably about 30 °, but may be changed within a range in which the action can occur.

The looper base 47 has a shaft portion 47a at the lower portion in the Z-axis direction, and is supported so that the shaft portion 47a can be rotated by the sewing machine frame 2. Moreover, the said shaft part 47a is formed in the cylindrical shape, and the spreader drive shaft 45 and the looper drive shaft 46 are inserted in the center of the shaft part 47a on the same axis line.

The upper end of the spreader drive shaft 46 extends to the lower vicinity of the attachment table 53, and the lower thread D which has passed through the lower thread guide hole 45a is the thread guide 55, the thread take-up spring 54, and the thread. The guide 56 is guided to the threading hole (not shown) of the left looper 49.

The left looper 49 and the left spreader 51 perform a double round bar when the needle bar 12 swings to the left and the needle falls. The right looper 50 and the right spreader 52 have the needle bar 12 right. When the needle falls by shaking, the single yarn round rod is performed.

Accordingly, the left looper 49 and the left spreader 51 move in the sewing operation direction in accordance with the needle drop timing according to the needle swing to the left, and the right looper 50 and the right spreader 52 move to the right. The operation is given from the looper drive shaft 46 so as to move in the sewing operation direction in accordance with the needle drop timing according to the above. In addition, while the spreaders 51 and 52 move together with the respective loopers 49 and 50, the respective spreaders 51 and 52 move from the spreader drive shaft 45 so as to widen the seal loop with respect to the respective loopers 49 and 50 at a predetermined timing. Action is given.

(Turning mechanism)

For example, the buttonhole sewing machine 10 swings the needle along the edge of the hole of the water droplet when the yarn is cut into a button hole having a straight line and a water droplet, such as a new eye hole. It is necessary to sew a swinging direction in a circumference. Thus, a swing mechanism 60 is provided which pivots the needle swing direction and pivots the arrangement of the loopers 49 and 50 and the spreaders 51 and 52.

Such swing mechanism 60 includes a needle bar pulley 61 for pivoting the swing table 38 of the needle swing mechanism 30 about the axis of the needle bar 12, and a looper drive shaft 46 and a spreader drive shaft having the same axis. A looper pulley 62 for turning the looper base 47 of the looper mechanism 40 around the 45 and a pulse motor for rotating the pulleys 61 and 62 through a pulley and a timing belt not shown. A phosphor turning motor 63 is provided. The axis of the needle bar 12, the spreader drive shaft 45 and the looper drive shaft 46 are arranged on the same axis, the pivot mechanism 60 is pivoted about the same axis with the needle bar and the looper base. .

As described above, the swinging table 38 is fitted by convex bodies from both sides with respect to the guide grooves formed on both sides thereof, and each convex member is supported by the needle bar pulley 61. Therefore, by swinging the needle bar pulley 61, the swinging table 38 also swings through each convex body, and as a result, the swinging direction of the needle can be turned.

In addition, since the needle bar pulley 61 loosely inserts the rocking table 38 into the central through-hole part whose inner diameter is set larger than the rocking table 38, it obstructs the rocking of the rocking table 38 and the needle bar 12. It is not supposed to be.

The looper pulley 62 is fixed to the lower portion of the looper base 47 and pivots the loopers 49 and 50 and the spreaders 51 and 52 together with the looper base 47.

In addition, the needle bar pulley 61 and the looper pulley 62 are both arranged to pivot about a common axis parallel to the Z axis direction through the center of the metal 14.

The swing motor 63 drives both the needle bar pulley 61 and the looper pulley 62 at the same rotation rate at the same time. The swing motor 63 is provided with an origin detector (not shown), and the detected origin position data is fed back to the CPU 101 described later and the swing motor drive circuit 63a described later.

(Moving mechanism)

The moving mechanism has a well-known structure and is disposed below the sewing needle 11 vertically, and includes a cloth lifter 71 having a sewing surface on which a work piece is placed, and a press fabric for holding the work piece on the cloth lifter 71. The presser foot cylinder 72 for switching the holding and releasing of the presser foot, the X-axis motor 73 which is a pulse motor for positioning the cloth lifter 71 in the X-axis direction, and the cloth lifter 71 are Y-axised. Y-axis motor 74, which is a pulse motor that moves in the direction and is positioned, is provided. In addition, each pulse motor 73, 74 is provided with an origin detector (not shown) to detect home position data, and the CPU 101, X-axis motor drive circuit 73a and Y-axis motor drive circuit 74a described later. ) To be fed back.

For example, when the cloth lifter 71 breaks a new eye hole, the cloth is conveyed at a predetermined pitch by the drive of the Y-axis motor 73 in the straight part of the new eye hole, and the needle is moved to the edge of the hole in the droplet part. The cloth is conveyed while aligning the needle drop position by the cooperation of the X-axis motor 72 and the Y-axis motor 73 so as to fall.

(Air discharge device for upper thread and air discharge device for lower thread)

The upper thread air discharging device 80 and the lower thread air discharging device 90 will be described based on FIGS. 5 to 7.

In addition, since the upper thread air discharge device 80 and the lower thread air discharge device 90 has the same internal structure, only the internal structure of the upper thread air discharge device 80 will be described, and the corresponding lower thread is used in the description. Regarding the internal structure of the air discharge device 90, a parenthesis denotes a symbol and duplicate description thereof will be omitted.

The upper thread air discharge device 80 (the lower thread air discharge device 90) includes a main body 81 (91) in which the cylinder portions 81a (91a) are opened along the Y-axis direction, and the cylinder portion 81a (91a). Piston member 82 (92) inserted and inserted to move forward and backward in the upper part), and the upper threaded air nozzle 83 which is maintained in the penetrating movement direction through the piston member 82 (92). The lower thread air nozzle 93 and the upper thread air nozzle 83 (the lower thread air nozzle 93) in the openings of the cylinder portions 81a (91a) along the direction of movement of the piston member 82 (92). The metal 84 (94) which keeps sliding movement possible, and the joint 85 for supplying air to the rear space and the front space of the piston member 82 (92) inside the cylinder part 81a (91a), respectively. , 86 (95, 96).

The main body 81 (91) is formed with a cylinder portion 81a (91a) that is a circular hole having a bottom along the Y-axis direction from one end surface in the Y-axis direction. The metal 84 (94) is fixed to the opening side of the cylinder portion 81a by press fitting or taper screw fixing.

In the cylinder portion 81a (91a), a piston member 82 (92) equipped with an upper thread air nozzle 83 (lower thread air nozzle 93) penetrates and is inserted therein, and the piston member 82 (92). A groove is formed in the outer circumferential surface of)), and the packing 82a (92a) which seals with the cylinder part 81a (91a) is accommodated. Moreover, the groove is formed also in the inner peripheral surface of the metal 84 similarly. The packing 84a (94a) which seals with the upper thread air nozzle 83 (the lower thread air nozzle 93) is accommodated.

Thereby, the inside of the cylinder part 81a (91a) is divided into two parts into the front space and the back space of the piston member 82 (92). The main body 81 (91) has an intake port 81b (91b) for supplying air to the space behind the cylinder portion 81a (91a) from the outside, and an intake port 81c (for supplying air to the front space). 91c)), and joints 85, 86 (95, 96) are connected to them, respectively. Each of the joints 85, 86 (95, 96) is connected to a compressed air supply source such as a compressor through the solenoid valves 87, 88 (97, 98).

When the solenoid valve 87 (97) is opened and compressed air is supplied from the joint 85 (95), the pressure inside the space behind the piston member 82 (92) increases, as shown in Fig. 5B. Similarly, the position where the piston member 82 (92) abuts the metal 84 (94) (operation position) or the upper thread air nozzle 83 (the lower thread air nozzle 93) is the needle bar 12 (spreader drive shaft 45). ), The air is injected into the needle bar opening 12b (drive shaft opening 45b).

In addition, when the solenoid valve 88 (98) is opened and compressed air is supplied from the joint 86 (96), the pressure inside the space in front of the piston member 82 (92) rises, and FIG. As shown, the piston member 82 (92) retracts the cylinder portion 81a (91a), and the rear end of the upper thread air nozzle 83 (the lower thread air nozzle 93) is the cylinder portion 81a (91a). The deepest portion (isolated position) of the abutment is inserted into the recessed portion 81d (91d) formed in the deepest portion thereof.

That is, the solenoid valve 88 (98), the piston member 82 (92), and the cylinder part 81a (91a) are the needle bar opening part 12b of the needle bar 12 (spreader drive shaft 45) located in a predetermined position. (Upper thread air nozzle 83 (lower thread air nozzle) between an operating position where the discharge port of the tip of the nozzle 83 (93) is connected to the drive shaft opening 45b and a standby position where the discharge port is isolated from the operating position. 93) and the upper thread retraction mechanism (lower thread retraction mechanism) which moves forward and backward.

The above-mentioned concave portion 81d (91d) is provided with air supplied to the inside of the rear space of the piston member 82 (92) when the piston member 82 (92) starts to advance. Since it is prevented from escaping from the practical air nozzle 93, it is possible to quickly start the movement at the time of advancing, and the rear end of the upper thread air nozzle 83 (the lower thread air nozzle 93) is concave by the advance. Sufficient air is supplied to advance the piston member 82 (92) even when exiting the portion 81d (91d).

The upper thread air nozzle 83 (the lower thread air nozzle 93) serves as a discharge port of air discharged to the needle bar 12 or the opening 12b (45b) of the spreader drive shaft 45. Since the abutment is adjacent to or close to the outer circumferential surface of the circular pipe-shaped needle bar 12 (spreader drive shaft 45), as shown in FIG. 5, the tip portion has an arc shape in accordance with the outer diameter of the needle bar 12 (spreader drive shaft 45). It is cut.

In addition, when the front end of the upper thread air nozzle 83 (lower thread air nozzle 93) is advanced until it touches the needle bar 12 (spreader drive shaft 45), the upper thread air nozzle 83 (lower thread air) The tip portion of the nozzle 93 may be made of an elastic material, or the elastic sheet may be attached to the tip surface of the nozzle or the opening 12b (45b) of the needle bar 12 (spreader drive shaft 45). The sealing between the distal end surface of the 83 (93) and the surface of the needle bar 12 (spreader drive shaft 45) can be achieved, so that air can be injected efficiently.

Further, the upper thread air nozzle 83 (the lower thread air nozzle 93) has a long circular cross section so that it does not rotate. If the upper thread air nozzle 83 is not rotated, other shapes such as polygons may be used. A slide groove for preventing rotation and a convex protrusion may be formed between the metal 84 (94) and the nozzle 83 (93) so as not to generate a gap.

Next, based on FIG. 6, the positional relationship of the extension formation position of the upper threaded air nozzle 83 and the needle bar opening 12b is demonstrated.

Needle bar 12 is moved up and down through the upper shaft 21 by the drive of the sewing machine motor 3 and at the same time the swing of the needle is made. The needle bar 12 is subjected to two swings and one swing of the needle for each round of the upper shaft 21. Here, when the upper axis angle at which the needle bar 12 is located at the top dead center is 0 °, when the upper axis angles are 0 ° and 180 °, the needle bar 12 is always at the top dead center position and the needle swing position is the neutral position (needle bar). The shank moving mechanism 20 and the needle swing mechanism 30 are set so that (12) is parallel to the Z-axis direction). These are identified by the encoder output.

In addition, when the upper shaft angles are 90 degrees and 270 degrees, the needle swing mechanism 30 is set so that the angle at which the needle swings left and right is maximum.

Moreover, the needle bar 12 is pivoted by the swing mechanism 60. Here, the rotation angle when the thread tension control device 15 provided on the needle bar 12 is located on the opposite side of the operator (vertical body portion 2b side: the state of FIG. 1) is 0 ° (home position), Normal sewing starts at 0 °.

Under the foregoing premise, when the needle bar 12 is in the state of the upper axis angle of 0 ° and the turning angle of 180 °, the needle bar opening 12b coincides with the extension forming position of the upper thread air nozzle 83, as shown in FIG. Arrangement is made so that

Next, based on FIG. 7, the positional relationship of the extension formation position of the lower thread air nozzle 93 and the drive shaft opening part 45b is demonstrated.

Spreader drive shaft 45 is moved up and down through the lower shaft 41 by the drive of the sewing machine motor 3, and performs two Shanghai-dong and one reciprocating Shanghai-dong per one revolution of the lower shaft (41). Here, since the upper shaft 21 and the lower shaft 41 are rotated at the same speed in synchronism, when the lower shaft angle, which becomes the needle bar top dead center, is 0 °, the spreader drive shaft 45 is neutral height (similar to that of the lower shaft angle 0 ° and 180 °). The middle of the point and the bottom dead center), and the looper mechanism 40 is set so that the spreader drive shaft 45 has the top dead center height and the bottom dead center height when the bottom axis angles are 90 ° and 270 °.

Further, the spreader drive shaft 45 is pivoted by the swing mechanism 60. When the above-mentioned linear turning angle is 0 °, when the spreader drive shaft 45 is in the state of the lower shaft angle 0 ° and the turning angle 0 °, as shown in FIG. 7, the driving shaft opening 45b is the lower thread air nozzle 93. As shown in FIG. The arrangement is made to coincide with the extension forming position.

(Control system of buttonhole sewing machine)

8 is a block diagram showing the control system of the buttonhole sewing machine 10.

The operation control means 100 includes a ROM 102 in which programs for executing various control or processing of a sewing machine are stored, a CPU 101 for executing various programs to perform a predetermined process or control, and a CPU 101 for processing. RAM 103 for storing various data at the time of execution, the interface 3b for connecting the drive circuit 3a of the sewing machine motor 3 to the CPU 101, and the drive circuit 73a for the X-axis motor 73. ) An interface 73b for connecting the CPU 101 to the CPU 101, an interface 74b for connecting the drive circuit 74a of the Y-axis motor 74 to the CPU 101, and a drive circuit for the swing motor 63. The interface 101b for connecting the 63a to the CPU 101 and the solenoid valve driving circuit 87a of the solenoid valve 87 for supplying air to the joint 85 of the upper threaded air nozzle 83 are provided with the CPU 101. ), An interface 88b for connecting the solenoid valve driving circuit 88a of the solenoid valve 88 for supplying air to the joint 86, the interface 88b for connecting the joint 87 to the CPU 101, and an air nozzle for the lower thread. ( The interface 97b which connects the solenoid valve drive circuit 97a of the solenoid valve 97 which supplies air to the joint 95 of 93, and the solenoid valve which supplies air to the joint 96 is connected. The interface 98b for connecting the solenoid valve driving circuit 98a of the 98 to the CPU 101 and the solenoid valve driving circuit 75a of the solenoid valve 75 for performing the operation switching of the presser foot cylinder 72 are connected. An interface 75b for connecting to the CPU 101 and an interface 106 for connecting the operation panel 104 and the start switch 105 to the CPU 101 are provided.

The operation panel 104 is provided with various switches for setting input and operation input of various data related to sewing, and in addition, the positions of the needle bar opening 12b and the drive shaft opening 45b are controlled at the time of the control for thread sewing described later. Threading switch 107 which executes the operation control in accordance with the extension formation positions of the nozzles 83 and 93, and nozzle switch 108 which executes the start and stop of the air discharge of each nozzle 83 and 93 and the threading control. And a reset switch 109 for terminating the process.

In addition, the start switch 105 is a switch for starting sewing.

Here, the contents of the sewing execution program and the sewing execution program, which are the main control programs stored in the ROM 102, will be described based on the case of cutting into the new eye hole of FIG.

According to the sewing execution program, it is divided into sections of K1 to K7 and controlled in order for each section.

First, bar-tacking is performed in the section K1 through the input of the start switch 105. That is, the CPU 101 drives the sewing machine motor 3 to oscillate the needle to a predetermined width to drive the Y-axis motor 74 while dropping the needle to advance sewing to the set pitch. Then, the X-axis motor 73 is driven to adjust the needle drop position to the sewing start position of the straight section of the new eye hole.

In sewing, the needle swing mechanism 30 is driven by the sewing machine motor 3 throughout the entire section, and the inner side of the needle swing mechanism 30 is close to the needle drop position of the outer side with respect to the new eye hole where the sewing needle 11 is a buttonhole. The so-called needle swing is made to swing the needle bar 12 in a predetermined needle swing direction so as to fall alternately to the needle drop position.

K2 is a section for sewing a straight portion of the new eye hole, and the CPU 101 drives the sewing machine motor 3 and the Y-axis motor 74 to execute the straight sewing in the forward direction.

K3 is a section for sewing the inclined shape of the water droplets of the new eye hole, and the CPU 101 drives the sewing machine motor 3 to drop the needle by needle fluctuation, while the Y-axis motor 74 and the X-axis By the cooperation of the motor 73, operation control for advancing the needle 11 in front of the inclined portion is executed.

K4 is a section for sewing the semi-circular arc shape of the water droplets of the new eye hole, the CPU 101 drives the sewing machine motor (3) to drive the turning motor (63) while performing the needle drop by needle fluctuation The swinging direction is gradually rotated 180 degrees, and the operation control is performed to position the needle to fall along the edge of the new eye hole by the cooperation of the Y-axis motor 74 and the X-axis motor 73.

K5 is a section for sewing the inclined shape of the water droplets of the new eye hole again, the CPU 101 drives the sewing machine motor 3 to perform the needle drop by needle fluctuation, while the Y-axis motor 74 and X By the cooperation of the shaft motor 73, operation control of advancing the needle 11 behind the inclined portion is executed.

K6 is a section for sewing the straight portion of the new eye hole again, and the CPU 101 drives the sewing machine motor 3 and the Y-axis motor 74 to execute the linear sewing in the retracting direction.

K7 is a section for executing the bolting again, the CPU 101 drives the sewing machine motor 3 to swing the needle to a predetermined width to drive the Y-axis motor 74 while dropping the needle, and at the same time retreats sewing. The sewing advances to the center by the drive of the X-axis motor 73 and ends.

Next, the control by the thread execution program will be described. Control of such threading is made when sewing is not performed.

That is, when the thread sewing switch 107 is input for the first time, the CPU 101 rotates the sewing machine motor 3 such that the upper and lower shaft angles are 0 degrees by the encoder output, and the turning motor 63 is rotated 180 degrees. The rotation control is made to match the position, whereby the position of the needle bar opening 12b is aligned in the extension direction of the upper thread air nozzle 83. In other words, the CPU 101 thus functions as upper thread sewing control means.

In addition, when the sewing thread switch 107 is input for the second time, the CPU 101 executes the operation control of setting the upper and lower shaft angles to 0 ° and setting the turning motor 63 to 0 ° by the sewing machine motor 3. As a result, the position of the drive shaft opening portion 45b is aligned with the forward forming direction of the lower thread air nozzle 93. In other words, the CPU 101 thus functions as a lower thread sewing control means.

Control by the thread execution program will be described in more detail based on the flowchart shown in FIG. 10.

First, when the thread sewing switch 107 is pressed (step S1), the presser foot cylinder 98 is driven to lower the presser foot (step S2), and the cloth lifter 71 is driven by the Y-axis motor 74. It moves to the predetermined highest retreat position (step S3).

Then, the sewing machine motor 3 is driven so that the upper shaft angle and the lower shaft angle are 0 degrees, and the turning motor 63 is turned to a position of 180 degrees (step S4). This angular position is detected by counting the number of pulses for the turning motor 63, which is a pulse motor. As a result, the position of the needle bar opening 12b is aligned with the extension forming direction of the upper threaded air nozzle 83.

Then, it is determined whether or not the nozzle switch 108 is pressed (step S5). If it is not pressed, the process proceeds to step S9, and when pressed, the solenoid valve 87 of the upper thread air discharge device 80 is pressed. The upper threaded air nozzle 83 starts to move forward (step S6). Then, when the tip portion of the upper threaded air nozzle 83 reaches the needle bar opening 12b, air is supplied into the upper thread guide portion 12a to generate airflow downward. As a result, since the needle bar opening 12b is attracted at the upper end of the needle bar 12, when the sewing machine operator approaches the end of the upper thread U, it is sucked and discharged from the lower end of the needle bar 12. Accordingly, the setting of the upper thread U is completed by hooking the upper thread U to the thread tension adjusting device 15 and inserting the upper thread U into the hole of the sewing needle 11.

Subsequently, when the nozzle switch 108 is input again (step S7), the solenoid valve 87 of the upper thread air discharge device 80 is closed and the solenoid valve 88 is opened to release the air from the nozzle 83. At the same time as the discharge is stopped, the upper threaded air nozzle 83 starts to move back (step S6). This solenoid valve 88 continues to open for a predetermined time and then closes, and the process proceeds to step S9.

In step S9, it is determined whether or not the second thread sewing switch 107 is input. If it is not input, the process returns to S4, and if it is input, the state where the upper and lower axis angles are 0 degrees is maintained, and the turning motor 63 turns to the position of 0 degrees (step S10). As a result, the position of the drive shaft opening portion 45b is adjusted to the front of the extension formation direction of the lower thread air nozzle 93.

Then, it is determined whether or not the nozzle switch 108 has been pressed (step S11), and if not pressed, the process proceeds to step S15, and when pressed, the solenoid valve 97 of the lower thread air discharge device 90 is pressed. It opens and the lower thread air nozzle 93 starts to move forward (step S12). When the tip portion of the lower thread air nozzle 93 reaches the drive shaft opening 45b, air is supplied into the lower thread guide hole 45a to generate airflow upward. Thereby, since the drive shaft opening part 45b becomes a suction state in the lower end part of the spreader drive shaft 45, when a sewing machine operator approaches the edge part of the lower thread D, it will be sucked and discharged from the upper end part of the spreader drive shaft 45. Accordingly, the lower thread D is passed through the thread take-up spring 54 and the thread guide members 55 and 56 to pass the thread sewing hole of the left looper 49, and furthermore, the lower thread D is passed through the needle plate 48. The setting of is completed.

Subsequently, when the nozzle switch 108 is input again (step S13), the solenoid valve 97 of the lower chamber air discharge device 90 is closed and the solenoid valve 98 is opened to release the air from the nozzle 93. At the same time as the discharge is stopped, the lower thread air nozzle 93 starts to move backward (step S14). The solenoid valve 98 continues to open for a predetermined time and then closes, and the process proceeds to step S15.

In step S15, it is determined whether a new thread sewing switch 107 has been input. If it is input, the process returns to step S4, and if it is not input, the presence or absence of input of the reset switch 109 is determined (step S16). If there is no input, the process returns to step S15.

When the reset switch 109 is input, the sewing machine motor 3 and the turning motor 63 return to the origin (step S17), and the cloth lifter 71 returns to the normal use position from the highest retracted position. (Step S18). Moreover, the presser foot cylinder 98 is driven to raise the presser foot (step S19), and the control on threading is terminated.

(Effect of Embodiment)

In the buttonhole sewing machine 10, the needle bar 12 is driven by the sewing machine motor 3 and the turning motor 63a under the control of the operation control means 100, and the discharge port of the upper thread air nozzle 83 is operated. Since it is arranged at a predetermined position at which the air can flow from the needle bar opening 12b to the needle bar opening 12b, that is, at the forward movement target position of the upper thread air nozzle 83, Air can be injected from the air nozzle 83, whereby the upper thread U can be inserted into the needle bar without using the thread sewing mechanism.

Similarly, the drive shaft opening 45 is driven from the discharge port of the lower thread air nozzle 93 by driving the spreader drive shaft 45 under the control of the operation control means 100 and the sewing machine motor 3 and the swing motor 63a. Since it is arranged at a predetermined position where air can be flowed to 45b), that is, at a forward movement target position of the lower thread air nozzle 93, the lower thread air nozzle with respect to the spreader drive shaft 45 disposed at the position. 93, it is possible to inject air, whereby the lower thread D can be inserted into the spreader drive shaft 45 without using the thread sewing mechanism.

Therefore, it is possible to prevent the occurrence of scratches in the upper thread guide portion 12a or the lower thread guide hole 45a.

In addition, the air gun does not need to be attached to the upper thread guide portion 12a or the inlet of the lower thread guide hole 45a, and therefore, it does not interfere with the insertion of the upper thread U or the lower thread D, and thus the upper thread U or the lower thread D ) Can be inserted easily and smoothly.

In addition, since both the upper thread air discharging device 80 and the lower thread air discharging device 90 can retract the nozzles 83 and 93 except when threading the upper thread U or the lower thread D, in particular, By moving to the retracted position during sewing, it is possible to avoid obstructions to the sewing needle 12 and the spreader drive shaft 45 which operate sewing.

In addition, in the buttonhole sewing machine 10, the needle bar 12 or the spreader drive shaft 45 can be aligned to a predetermined position at which air injection is enabled by the input operation of the thread sewing switch 107. The operation of inserting the upper thread U into the upper thread guide portion 12b of the c) or the operation of inserting the lower thread D into the lower thread guide hole 45b of the spreader drive shaft 45 can be performed smoothly and arbitrarily. .

(Etc)

In addition, in the buttonhole sewing machine 10 of the above embodiment, the spreader drive shaft 45 is inserted inside the looper drive shaft 46, but the looper drive shaft 46 is thinned to the looper drive shaft inside the spreader drive shaft 45. (46) may be inserted. In this case, the lower thread guide hole and the drive shaft opening part are formed in the looper drive shaft 46, and the lower thread air nozzle 93 preferably injects air to the looper drive shaft 46.

In the upper thread air discharge device 80 and the lower thread air discharge device 90, movement of the nozzle and discharge of air are performed by supplying air from the same solenoid valve, but separately by a separate solenoid valve. You may.

In addition, although the thread sewing switch 107 is configured to be used jointly for the insertion of the upper thread U and the insertion of the lower thread D, the upper thread sewing switch and the lower thread sewing switch in the insertion of the upper thread U and the insertion of the lower thread D. It may be configured to install separately.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side cross-sectional view of part of a buttonhole sewing machine according to an embodiment of the present invention.

2 is an enlarged cross-sectional view showing the upper periphery of the needle bar.

3 is an enlarged sectional view seen from above of the upper periphery of the needle bar.

4 is an enlarged cross-sectional view showing the periphery of the looper mechanism.

Fig. 5 is a sectional view seen from above showing the internal structure of the upper thread air discharge device and the lower thread air discharge device, and Fig. 5 (A) shows a state where the nozzle is in a discharge position, and Fig. 5 (B) shows that the nozzle is in the atmosphere Represents a state in position.

6 is a sectional view seen from the side showing the internal structure of the upper thread air discharge device.

7 is a sectional view seen from the side showing the internal structure of the lower air discharge device.

8 is a block diagram showing a control system of a buttonhole sewing machine.

9 is an explanatory diagram showing an example of a needle movement in the case of cutting into a new eye hole.

10 is a flowchart showing the control process contents for thread sewing.

11 is a plan view of the threading mechanism.

        Explanation of symbols on the main parts of the drawings

10: buttonhole sewing machine

11: sewing needle

12: needle bar

12a: Upper thread guide

12b: needle bar opening

20: Shanghai East Organization

30: needle swing mechanism

40: looper mechanism

47: Rupertoe

49: left looper

50: right looper

51: left spreader

52: right spreader

60: turning mechanism

70: moving mechanism

80: upper air discharge device (upper thread retraction mechanism)

90: air discharge device for the lower thread (retraction mechanism for the lower thread)

100: motion control means (upper thread sewing control means, lower thread sewing control means)

107: thread sewing switch (upper thread sewing switch, lower thread sewing switch)

U: upper thread

Claims (6)

A needle bar having a needle thread having a hole formed therein for inserting the upper thread at the lower end thereof, and communicating with the lower thread to form the upper thread guide hole for guiding the upper thread; Shanghai copper mechanism connected to the needle bar to move the needle bar up and down, A needle swing mechanism for swinging the needle bar in a predetermined needle swing direction; A looper mechanism installed at a lower side of the sewing machine sewing surface, the looper and the spreader swinging to bind the lower thread to the upper thread are supported on the looper base; And a revolving mechanism arranged in association with the needle bar and the looper base to pivot the needle bar and the looper base about the same axis, and forming a needle stitch around the buttonhole of the fabric. as, A needle bar opening communicating with the upper thread guide hole from an outer side surface of the needle bar, the needle bar opening being inclined so that air flowing from the outside flows downward from the inside of the upper thread guide hole; An upper nozzle air nozzle having a discharge port for discharging air to the needle bar opening, and arranged on a side of the shanghai east path of the needle bar; The upper thread sewing control means for controlling the shank moving mechanism, the needle swing mechanism, and the turning mechanism to adjust the position of the needle bar to a predetermined position where air can flow from the discharge port of the upper thread air nozzle to the needle bar opening; Buttonhole sewing machine characterized in that. The method of claim 1, An upper thread retraction mechanism for moving the upper thread air nozzle forward and backward between an operating position where the discharge port is connected to the needle bar opening of the needle bar positioned at the predetermined position and a standby position where the discharge port is isolated from the operating position. Equipped, The upper thread sewing control means controls the upper thread retracting mechanism to position the needle bar at the predetermined position and to control the upper thread air nozzle from the standby position to the operating position. Sewing machine. The method according to claim 1 or 2, The upper thread sewing switch for outputting the upper thread sewing command signal by an input operation, And said upper thread sewing control means controls a drive source of said shank moving mechanism, needle swing mechanism and swing mechanism such that said needle bar is in said predetermined stop position in response to said upper thread sewing command signal. A needle bar that holds a sewing needle having a hole into which the upper thread is inserted, at the bottom; Shanghai copper mechanism connected to the needle bar to move the needle bar up and down, A needle swing mechanism for swinging the needle bar in a predetermined needle swing direction; A drive shaft having a hollow lower thread guide hole for guiding the lower thread from the lower end to the upper end, A looper mechanism installed below the sewing surface of the sewing machine and supporting the looper and the spreader swinging to bind the lower thread to the upper thread on a looper base, and swinging the looper or the spreader by moving the drive shaft up and down; A turning mechanism arranged in association with the needle bar and the looper base to pivot the needle bar and the looper base about the same axis, wherein the needle stitches are wound around the buttonhole of the fabric by the respective mechanisms. As a buttonhole sewing machine to form, A drive shaft opening communicating with the lower thread guide hole from an outer side of the drive shaft, the drive shaft opening being inclined such that air flowing from the outside flows upward from the lower side of the lower thread guide hole; An air nozzle for a lower thread having a discharge port for discharging air to the opening of the drive shaft, and arranged at a side of the drive shaft; And a thread sewing control means for controlling the looper mechanism and the swing mechanism to adjust the position of the drive shaft to a predetermined position at which air can flow from the discharge port of the lower thread air nozzle to the drive shaft opening. Buttonhole sewing machine. The method of claim 4, wherein A lower thread retraction mechanism for moving the lower thread air nozzle back and forth between an operating position at which the discharge port is connected to a drive shaft opening of the drive shaft located at the predetermined position and a standby position at which the discharge port is isolated from the operating position; Equipped, The lower thread sewing control means controls the lower thread retracting mechanism to position the drive shaft at the predetermined position and to move the lower thread air nozzle from the standby position to the operating position. . The method according to claim 4 or 5, A bobbin thread switch for outputting a bobbin thread command signal by an input operation; And the lower thread sewing control means controls a drive source of the looper mechanism and the turning mechanism so that the needle bar is at the predetermined stop position in response to the lower thread sewing command signal.

Images