DE102016102024A1 - sewing machine - Google Patents

Abstract

The sewing machine in which a pin hole is formed in a throat plate or in a feed dog comprises a lower thread insertion mechanism, a sewing start stop holding mechanism, a first thread cutting device, and a control device. The lower thread insertion mechanism includes an air blowing mechanism that introduces a sewing start end of a lower thread from an underside of the needle hole through air into the needle hole. The sewing start holding mechanism holds the sewing start end of the inserted lower thread above the throat plate. The first thread cutting device cuts the sewing start end of the lower thread held by the sewing start holding mechanism. The controller controls operations of the sewing machine.

Description

BACKGROUND OF THE INVENTION

Field of the invention

The present invention relates to a sewing machine with a thread cutting device.

State of the art

A sewing machine of the prior art comprises a needle thread catching mechanism which catches a sewing start end of a top thread from a sewing needle which makes a stitch point of a first stitch below a throat plate using a catching member and which releases the sewing start end of the upper thread after the stitch point of a plurality of stitches and Occurrence of a sewing error due to deviation of the sewing start end of the upper thread from the stitch point position of the first stitch by lifting a thread take-up lever prevented.

The catching member of the catching mechanism includes opposing surfaces that can be brought into contact and separated from each other, executes a stitching point of a needle between the facing surfaces, closes the facing surfaces to catch the sewing start end of the upper thread when sewing start end of the upper thread Upper thread is pulled out by an edge of a shuttle down.

However, when the sewing start end of the upper thread is caught in this manner, it is found that the sewing start end of the upper thread hangs down long from the stitch point position of the first stitch on the back side of a sewing material.

Therefore, in the prior art upper thread catching mechanism, a holding force of the facing surfaces of the catching member is more reduced after the stitching point of the first stitch than in a normal state, and the sewing start end of the upper thread is caused to slide such that the sewing start end of the upper thread is not completely pulled out of the catch member by lifting the thread take-up lever, whereby the holding force is adjusted to reduce the catch length (see, for example JP-A-2006-320365 ).

SUMMARY OF THE INVENTION

Although it is considered in the sewing machine of the prior art to make the sewing start end of a top thread shorter; however, a sewing start end of a lower thread still remains and hangs down from a cloth long, resulting in a deterioration of the sewing quality. To improve the sewing quality, the sewing start end of the lower thread must be manually cut after sewing is completed, thereby causing an increase in the work load.

• (1) Bei einer Nähmaschine gemäß vorliegender Erfindung ist ein Nadelloch in einer Stichplatte oder in einem Transporteur ausgebildet. Die Nähmaschine umfasst einen Unterfadeneinführmechanismus, einen Nähstartendehaltemechanismus, eine erste Fadenschneideinrichtung und eine Steuereinrichtung. Der Unterfadeneinführmechanismus umfasst einen Luftblasmechanismus, welcher ein Nähstartende eines Unterfadens von einer Unterseite der Stichplatte her durch Luft in das Nadelloch einführt. Der Nähstartendehaltemechanismus hält das Nähstartende des eingeführten Unterfadens oberhalb der Stichplatte. Die erste Fadenschneideinrichtung schneidet das durch den Nähstartendehaltemechanismus gehaltene Nähstartende des Unterfadens. Die Steuereinrichtung steuert Operationen der Nähmaschine.
• (2) Bei der Nähmaschine nach (1) umfasst der Luftblasmechanismus eine Düse, welche Luft zu dem Nadelloch hin ausstößt. An einer Spitze der Düse weist die Düse einen Schlitz auf. Der Schlitz ist dazu ausgebildet, das Nähstartende des Unterfadens zu führen und zu halten.
• (3) Bei der Nähmaschine nach (1) oder (2) umfasst der Nähstartendehaltemechanismus eine Gleitplatte, welche ein Oberfadenfangloch und ein Unterfadenfangloch aufweist. Das Oberfadenfangloch und das Unterfadenfangloch sind in einer Gleitrichtung angeordnet. Das Oberfadenfangloch und das Unterfadenfangloch sind dazu ausgebildet, das Nähstartende des Unterfadens und ein Nähstartende eines Oberfadens zwischen der Gleitplatte und einer zugewandten Oberfläche der Stichplatte zu klemmen und zu halten. Die Gleitplatte ist in eine Oberfadeneinführposition, in eine Unterfadeneinführposition und in eine Auslaufposition bewegbar. In der Oberfadeneinführposition ist das Oberfadenfangloch dem Nadelloch überlagert. In der Unterfadeneinführposition ist das Unterfadenfangloch dem Nadelloch überlagert. In der Auslaufposition sind sowohl das Unterfadenfangloch als auch das Oberfadenfangloch von dem Nadelloch getrennt.
• (4) Bei der Nähmaschine nach (3) klemmt und hält die Gleitplatte das Nähstartende des Oberfadens und das Nähstartende des Unterfadens zwischen der Gleitplatte und der zugewandten Oberfläche der Stichplatte in der Auslaufposition. Die Steuereinrichtung steuert die Nähmaschine, um: vor einem Stichpunkt eines ersten Stichs die Gleitplatte in der Unterfadeneinführposition anzuordnen, das Nähstartende des Unterfadens von der Unterseite her durch Verwendung des Luftblasmechanismus in das Nadelloch und in das Unterfadenfangloch einzuführen, nach Einführung des Nähstartendes des Unterfadens die Gleitplatte in der Oberfadeneinführposition anzuordnen, durch den Stichpunkt des ersten Stichs das Nähstartende des Oberfadens in das Nadelloch und in das Oberfadenfangloch einzuführen, nach Einführung des Nähstartendes des Oberfadens die Gleitplatte in der Auslaufposition anzuordnen und bei und nach einem Stichpunkt eines zweiten Stichs das Nähstartende des Oberfadens und das Nähstartende des Unterfadens durch Verwendung der ersten Fadenschneideinrichtung zu schneiden.
• (5) Bei der Nähmaschine nach (3) oder (4) ist ein Messer der ersten Fadenschneideinrichtung unterhalb der Gleitplatte angeordnet. Die Nähmaschine umfasst ferner einen Fadenziehmechanismus. Der Fadenziehmechanismus führt eine Abwärtsbewegung aus, wenn die Gleitplatte in der Auslaufposition angeordnet ist, zieht das Nähstartende des Oberfadens und das Nähstartende des Unterfadens, welche durch die Gleitplatte ausgezogen werden, und bringt das Nähstartende des Oberfadens und das Nähstartende des Unterfadens mit der ersten Fadenschneideinrichtung in Eingriff. Die Steuereinrichtung steuert die Nähmaschine, um nach Abwärtsbewegung des Fadenziehmechanismus das Nähstartende des Oberfadens und das Nähstartende des Unterfadens durch Verwendung der ersten Fadenschneideinrichtung zu schneiden.
• (6) Die Nähmaschine nach einem der Punkte (3) bis (5) umfasst ferner eine zweite Fadenschneideinrichtung. Die zweite Fadenschneideinrichtung schneidet den Unterfaden bei Abschluss eines ersten Nähvorgangs und hält ein Ende des geschnittenen Unterfadens auf einer Schiffchenseite als ein Nähstartende für einen zweiten Nähvorgang, welcher als Nächstes auf den ersten Nähvorgang folgt. Der Unterfadeneinführmechanismus umfasst einen Haltefreigabemechanismus und einen Fadenhandhabungsmechanismus. Der Haltefreigabemechanismus gibt einen Haltezustand des Nähstartendes des Unterfadens, welches durch die zweite Fadenschneideinrichtung gehalten wird, frei. Der Fadenhandhabungsmechanismus zieht das Nähstartende des Unterfadens zur Unterseite des Nadellochs.
• (7) Bei der Nähmaschine nach (6) umfasst der Fadenhandhabungsmechanismus ein Fadenhandhabungsglied, welches durch eine Vorwärtsbewegung des Fadenhandhabungsglieds das Nähstartende des Unterfadens zur Unterseite des Nadellochs zieht. Das Fadenhandhabungsglied umfasst einen ersten geneigten Bereich, einen konkaven Bereich und einen zweiten geneigten Bereich. Der erste geneigte Bereich ist an einer Spitze des Fadenhandhabungsgliedes gebildet, um das Nähstartende des Unterfadens aufwärts zu bewegen. Der konkave Bereich ist in einem oberen Teil der Spitze gebildet, um das Nähstartende des Unterfadens zu fangen. Der zweite geneigte Bereich ist im Inneren des konkaven Bereichs gebildet, um das Nähstartende des Unterfadens abwärts zu bewegen. Ein oberes Ende des zweiten geneigten Bereichs ist höher als ein oberes Ende des ersten geneigten Bereichs.
• (8) Bei der Nähmaschine nach (6) oder (7) wird vor dem Einführen des Nähstartendes des Unterfadens in das Nadelloch und in das Unterfadenfangloch durch Verwendung des Luftblasmechanismus die Nähmaschine von der Steuereinrichtung gesteuert, um den Fadenhandhabungsmechanismus anzutreiben, das Nähstartende des Unterfadens zur Unterseite des Nadellochs zu ziehen, und um den Haltefreigabemechanismus anzutreiben, den Haltezustand des Nähstartendes des Unterfadens, welches durch die zweite Fadenschneideinrichtung gehalten wird, freizugeben.

It is an object of the present invention to make a sewing start end of a lower thread remaining on a fabric shorter.

• (1) In a sewing machine according to the present invention, a pinhole is formed in a throat plate or in a feed dog. The sewing machine includes a lower thread insertion mechanism, a Nähstartendehaltemchanismus, a first thread cutting device and a control device. The lower thread insertion mechanism includes an air blowing mechanism that introduces a sewing start end of a lower thread from a lower side of the throat plate by air into the needle hole. The sewing start holding mechanism holds the sewing start end of the inserted lower thread above the throat plate. The first thread cutting device cuts the sewing start end of the lower thread held by the sewing start holding mechanism. The controller controls operations of the sewing machine.
• (2) In the sewing machine of (1), the air blowing mechanism includes a nozzle which discharges air toward the needle hole. At a tip of the nozzle, the nozzle has a slot. The slot is adapted to guide and hold the sewing start end of the lower thread.
• (3) In the sewing machine of (1) or (2), the sewing start stop holding mechanism includes a slide plate having a top thread catching hole and a bottom thread catching hole. The upper thread catching hole and the lower thread catching hole are arranged in a sliding direction. The upper thread catching hole and the lower thread catching hole are formed to clamp and hold the sewing start end of the lower thread and a sewing start end of an upper thread between the sliding plate and a facing surface of the needle plate. The slide plate is movable into an upper thread insertion position, a lower thread insertion position, and a run-out position. In the upper thread insertion position, the upper thread catching hole is superimposed on the needle hole. In the lower thread insertion position, the lower thread catching hole is superimposed on the needle hole. In the discharge position, both the lower thread catching hole and the upper thread catching hole are separated from the needle hole.
• (4) In the sewing machine of (3), the slide plate clamps and holds the sewing start end of the upper thread and the sewing start end of the lower thread between the slide plate and the facing surface of the throat plate in the run-out position. The Control means controls the sewing machine to: before a stitch point of a first stitch to arrange the slide plate in the lower thread insertion position, to introduce the sewing start end of the lower thread from the lower side by using the air blowing mechanism into the needle hole and the lower thread catching hole, after introduction of the sewing start end of the lower thread, the slide plate in FIG to arrange the upper thread insertion position, to introduce the sewing start end of the upper thread into the needle hole and the upper thread catch hole by the stitch point of the first stitch, to arrange the slide plate in the run-out position after introduction of the sewing start end of the upper thread, and sewing start end of the upper thread and after a stitch point of a second stitch Sewing start end of the lower thread to be cut by using the first thread cutting device.
• (5) In the sewing machine of (3) or (4), a knife of the first thread cutting device is disposed below the sliding plate. The sewing machine further includes a thread pulling mechanism. The thread pulling mechanism performs a downward movement when the slide plate is disposed at the run-out position, pulls the sewing start end of the upper thread and the sewing start end of the lower thread pulled out by the slide plate, and brings in the sewing start end of the upper thread and the sewing start end of the lower thread with the first thread cutting device intervention. The control means controls the sewing machine to cut, after downward movement of the thread pulling mechanism, the sewing start end of the upper thread and the sewing start end of the lower thread by using the first thread cutting device.
• (6) The sewing machine according to any one of (3) to (5) further comprises a second thread cutting device. The second thread cutting device cuts the lower thread upon completion of a first sewing operation, and holds one end of the cut lower thread on a shuttle side as a sewing start end for a second sewing, which is next to the first sewing. The lower thread insertion mechanism includes a hold release mechanism and a thread handling mechanism. The holding release mechanism releases a holding state of the sewing start end of the lower thread held by the second thread cutting device. The thread handling mechanism pulls the sewing start end of the lower thread to the bottom of the needle hole.
• (7) In the sewing machine according to (6), the thread handling mechanism includes a thread handling member which pulls the sewing start end of the lower thread toward the lower side of the needle hole by advancing the thread handling member. The thread handling member includes a first inclined portion, a concave portion, and a second inclined portion. The first inclined portion is formed at a tip of the thread handling member to move the sewing start end of the lower thread upwards. The concave portion is formed in an upper part of the tip to catch the sewing start end of the lower thread. The second inclined portion is formed inside the concave portion to move the sewing start end of the lower thread downwards. An upper end of the second inclined portion is higher than an upper end of the first inclined portion.
• (8) In the sewing machine of (6) or (7), before the sewing start end of the lower thread is inserted into the needle hole and the lower thread catch hole by using the air blowing mechanism, the sewing machine is controlled by the controller to drive the thread handling mechanism, the sewing start end of the lower thread to To pull bottom of the needle hole, and to drive the holding release mechanism to release the holding state of the sewing start end of the lower thread, which is held by the second thread cutting device.

In the sewing machine of the present invention, a sewing start end of a lower thread is blown upward from the lower side and inserted into the needle hole through the lower thread insertion mechanism, the sewing start end of the lower thread is held above the stitch plate by the sewing start stop holding mechanism, and the held sewing start end of the lower thread is passed through the first thread cutting device cut. Accordingly, it is possible to cut a sewing start end of a lower thread from a cloth without using a manual operation and to shorten the sewing start end of the bobbin thread remaining in the cloth, thereby achieving an improvement in the sewing quality. Since no manual operation is required, it is possible to reduce a workload of an operation for cutting a sewing start end of a lower thread.

BRIEF DESCRIPTION OF THE FIGURES

1 Fig. 10 is a side view showing a configuration in the vicinity of a needle in a mechanical feed sewing machine.

2 Fig. 10 is a plan view of an end opposite to a stand body portion of a bed of the sewing machine.

3 Fig. 10 is a block diagram showing a control system of the sewing machine.

4 Fig. 10 is a side view showing a configuration in the vicinity of a horizontal boat.

5 is a perspective view of a thread handling mechanism.

6 is a plan view of a thread handling mechanism.

7A FIG. 15 is an enlarged plan view showing positions before and after operation of a yarn handling hook when a lower thread is disposed at a low position, and FIG 7B Fig. 10 is an enlarged plan view showing positions before and after operation of the thread handling hook when a lower thread is disposed at a high position.

8th Fig. 15 is a perspective view showing a state in which a nozzle of an air blowing mechanism moves backward and showing a configuration in the vicinity of a horizontal boat.

9 Fig. 15 is a perspective view showing a state in which a nozzle of an air blowing mechanism advances, showing a configuration in the vicinity of a horizontal boat.

10 is a perspective view of a flat nozzle.

11 is a cross-sectional view of the flat nozzle.

12 is a perspective view of an annular nozzle.

13 is a cross-sectional view of the annular nozzle.

14 is a plan view of a throat plate.

15 Fig. 13 is a perspective view of the vicinity of the throat plate showing an operation of cutting sewing start ends of a lower thread and a upper thread.

16 FIG. 15 is a perspective view of the vicinity of the throat plate showing and operating the operation of cutting sewing start ends of a lower thread and an upper thread 15 followed.

17 FIG. 15 is a perspective view of the vicinity of the throat plate showing and operating the operation of cutting sewing start ends of a lower thread and an upper thread 16 followed.

18 FIG. 15 is a perspective view of the vicinity of the throat plate showing and operating the operation of cutting sewing start ends of a lower thread and an upper thread 17 followed.

19 FIG. 15 is a perspective view of the vicinity of the throat plate showing and operating the operation of cutting sewing start ends of a lower thread and an upper thread 18 followed.

20 FIG. 15 is a perspective view of the vicinity of the throat plate showing and operating the operation of cutting sewing start ends of a lower thread and an upper thread 19 followed.

21 is a perspective view of a first thread cutting device.

22 FIG. 15 is a perspective view showing a thread cutting operation using a movable knife and a fixed knife of the first thread cutting device. FIG.

23 FIG. 16 is a perspective view showing the thread-cutting operation using the movable knife and the fixed knife of the first thread cutting device. FIG 22 followed.

24 FIG. 16 is a perspective view showing the thread-cutting operation using the movable knife and the fixed knife of the first thread cutting device. FIG 23 followed.

25 Fig. 12 is a side view showing the thread-cutting operation using the movable knife and the fixed knife of the first thread-cutting device.

26A FIG. 11 is an operation diagram showing an operation of cutting sewing start ends of a lower thread and an upper thread; FIG. 26B is an operation diagram which 26A connects, and 26C is an operation diagram which 26B followed.

27A FIG. 12 is an operation diagram showing an operation of cutting sewing start ends of the lower thread and the upper thread and on 26C connects, 27B is an operation diagram which 27A connects, and 27C is an operation diagram which 27B followed.

28A FIG. 12 is an operation diagram showing an operation of cutting sewing start ends of the lower thread and the upper thread and on 27C connects, 28B is a Operation diagram, which on 28A connects, and 28C is an operation diagram which 28B followed.

29 FIG. 12 is an operation diagram showing an operation of cutting sewing start ends of the lower thread and the upper thread and on 28C followed.

30 Fig. 10 is a flowchart showing a control flow of the operation of cutting the sewing start ends of the lower thread and the upper thread.

31 Fig. 12 is a perspective view showing another example of a thread pulling mechanism.

32 FIG. 10 is a plan view showing another example of a sewing start stopping mechanism. FIG.

33 Fig. 16 is a perspective view showing another example of the sewing start holding mechanism.

34 FIG. 15 is a perspective view showing a regulating plate of a thread pulling member. FIG.

LONG DESCRIPTION

Overview of the sewing machine

The following is a sewing machine 10 according to the present invention with reference to the accompanying drawings. As in 1 shown, it is the sewing machine 10 around a so-called mechanical feed sewing machine comprising a needle bar and a sewing needle 11 (please refer 18 ) which moves up and down and vibrates forward and backward in a cloth conveying direction, a transport foot 12 , which moves up and down and oscillates forwards and backwards synchronously with the needle bar, a presser foot 13 who is with the transport foot 12 alternately moved up and down, and a transporter 14 which moves periodically in the transport direction synchronously with the needle bar.

That is, the sewing machine with mechanical feed is in the transport foot 12 a through hole 12a formed by the sewing needle 11 is dived through, and in the transporter 14 is a pinhole 15 formed by the sewing needle 11 is dived through.

When the sewing needle 11 and the transport foot 12 move down, the feed dog moves 14 upwards, and these move in the direction of the material transport towards the front. Accordingly, a fabric is through the transport foot 12 and the transporter 14 clamped, from the sewing needle 11 pierced and transported in the fabric transport direction to the front.

When the sewing needle 11 and the transport foot 12 move up, the presser foot moves 13 down, the sewing needle 11 and the transport foot 12 move backwards while the presser foot 13 the fabric is pressed and a stitch point is made while the fabric is being transported again.

The sewing machine with mechanical feed is the pinhole 15 in the transporter 14 formed, which moves in a circumferential movement, and the position of the needle hole 15 changes with the circumferential movement of the carrier 14 ; the following description of the relative positional relationship to the pinhole 15 However, based on the premise that the position of the pinhole 15 the position is where the transporter 14 at a arm shaft angle of 0 ° (a top dead center of the needle bar).

The sewing machine 10 includes elements conventionally included in a mechanical feed sewing machine, for example, a needle bar up / down moving mechanism, a cloth conveying mechanism, a shuttle driving mechanism, a thread tension tray, and a thread take-up lever; however, these elements are known and therefore a detailed description thereof is omitted.

In the following description is in a state where the sewing machine 10 is placed on a horizontal plane, the vertical top is defined as "top", the vertical bottom is defined as "bottom", the downstream side in the cloth transport direction is defined as "front", the upstream side in the cloth transport direction (operator side) is defined as "rear" , the left side in a forward facing state is defined as "left" and the right side in the forward facing state is defined as "right".

2 Figure 11 is a plan view of an end resting on the pillar body region side of a bed 16 the sewing machine 10 opposite side (the left side), wherein an upper cover and some internal elements are not shown there. 3 is a block diagram illustrating the overall configuration of the sewing machine.

As shown in the figures, the sewing machine comprises 10 a throat plate 17 which on a sewing bed 16 is arranged, a horizontal boat 18 , which concerning the throat plate 17 is arranged bottom right, a lower thread insertion mechanism 2 , which is a Nähstartende a lower thread from below into the needle hole 15 introduces a sewing start holding mechanism 50 which is the sewing start end of the needle hole 15 dipping lower thread and an upper thread above the throat plate 17 holds, a first thread cutting device 60 which is that of the Nähstartendehaltemechanismus 50 held sewing start end of the lower thread cuts, a second thread cutting device 70 which cuts a bobbin thread consumed in sewing and holds one end of the cut bobbin thread lower thread as a sewing start end for the next sewing, a thread pulling mechanism 80 , which shows the sewing start ends of the upper thread and the lower thread passing through a sliding plate 51 of the sewing start holding mechanism 50 pulled in a sliding direction, pulling down, a catching mechanism 19 , which cut pieces of the lower thread and the upper thread, which from the first thread cutting device 60 be cut, catches, and a control device 110 which are the units of the sewing machine 10 controls.

The bobbin thread insertion mechanism 2 includes a hold release mechanism 20 which detects the holding state of the sewing start end of the bobbin thread by the second thread cutting device 70 releases a thread handling mechanism 30 , which the sewing start end of the lower thread to the bottom of the needle hole 15 pulls, and an air blower mechanism 40 that controls the sewing start end of the bobbin thread whose hold state is released by using air in the needle hole 15 introduces.

As described above, the sewing machine includes 10 a needle-up / down movement mechanism which causes the needle bar and sewing needle 11 move up and down and swing forward and backward, a press-up-down movement mechanism, which causes the transport foot 12 and the presser foot 13 alternately move up and down, and a cloth transport mechanism which causes the feed dog 14 through the opening of the needle plate 17 emerges and recedes, and which transports a fabric forward and backward, and a shuttle mechanism which the horizontal boat 18 to a rotational movement that is twice the upward and downward movement speed of the sewing needle 11 is, these mechanisms use a sewing motor as a common drive source.

Hereinafter, the above-mentioned elements will be described sequentially.

Second thread cutting device

4 is a side view showing the configuration in the vicinity of the horizontal boat 18 shows, and 8th is a perspective view thereof. As in the 2 to 4 and in 8th shown is the second thread trimmer 70 arranged at a position which is lower than the needle plate 17 and with respect to the pinhole 15 located to the front. The second thread cutting device 70 includes a hook-shaped movable knife 71 , a solid knife 72 , which is fixed to a sewing frame, and a leaf spring 73 which the movable knife 71 against the solid knife 72 suppressed.

The second thread cutting device 70 Catches and cuts one from the needle hole 15 to the horizontal boat 18 drooping upper thread and bobbin thread after the stitch point of the last stitch and holds one end of the cut lower thread. The bottom thread end serves as the sewing start end for the next sewing operation.

The moving knife 71 is long in the front-rear direction, is in a state in which the tip faces the rear, via a linkage with a second Fadenschneidsolenoid 74 connected and leads through the second thread cutting solenoid 74 a back and forth, comprising a movement towards the rear side to catch an upper thread and a lower thread and a movement towards the front to the lower position, from.

Accordingly, the tip of the movable knife points 71 a sharp-pointed shape, wherein in the vicinity of the tip, a hook-shaped, beveled portion is formed and in the interior of the folded portion, a front-facing cutting edge is formed.

The solid knife 72 is above the moving knife 71 arranged and its lower surface comes with the upper surface of the movable knife 71 in sliding contact. The solid knife 72 has a cantilever shape which extends toward the rear, and at its tip a cutting edge directed towards the rear is formed. Accordingly, the upper thread and the lower thread passing through the folded portion of the movable knife 71 trapped in an outward path of the toe and aft, in a return path of going and going through the cutting edge of the movable knife 71 and the cutting edge of the fixed blade 72 clamped and cut.

As the leaf spring 73 the movable knife 71 from the bottom presses to the top, the movable knife can 71 against the solid knife 72 can be pressed and it can be prevented that a gap between them, whereby reliable cutting is made possible.

Through the leaf spring 73 For example, the end of the cut lower thread on the shuttle side (the sewing start end for the next sewing operation) between the movable knife 71 and the leaf spring 73 be clamped and held, and thus it is possible to clarify the position of the sewing start end of the lower thread.

Thread handling mechanism

The thread handling mechanism 30 has a function of guiding a sewing start end of a lower thread to an appropriate position such that the air blowing mechanism 40 the sewing start end up into the needle hole 15 and a function of unwinding the bobbin from a bobbin in the horizontal shuttle 18 by a suitable length.

5 is a perspective view of the thread handling mechanism 30 . 6 Fig. 10 is an enlarged plan view showing positions of the thread handling mechanism before and after operation of a thread handling hook to be described 31 shows, and 7 is a diagram showing the behavior of the lower thread at the tip of the thread handling hook 31 shows. As in the 2 and 5 shown is the thread handling mechanism 30 arranged at a position which is lower than the throat plate 17 and with respect to the pinhole 15 a little to the left, towards the back.

The thread handling mechanism 30 includes a thread handling hook 31 as a thread handling member, which is the sewing start end of the lower thread coming from the horizontal shuttle 18 to the second thread cutting device 70 suspended, by a forward and backward movement, a first thread handling air cylinder 32 , which the thread handling hook 31 causes a forward and backward movement, a support plate 33 which the thread handling mechanism 30 as a whole supports, a support member 34 , which is the first thread handling air cylinder 32 allows in a predetermined direction over the support plate 33 to slide, and a second thread handling air cylinder 35 , which the first thread handling air cylinder 32 to a reciprocating motion in the predetermined direction relative to the support plate 33 causes.

The support plate 33 is designed to be horizontal on the sewing bed 16 to be attached, and has a trained in her slot 331 on which the forward and backward movement direction of the first yarn handling air cylinder 32 leads. The slot 331 is formed obliquely forward to the right, and when the first thread handling air cylinder 32 through the second yarn handling air cylinder 35 is ejected, the first thread handling air cylinder leads 32 a forward movement in a right-dashed direction.

The support member 34 includes a slider (not shown), which in the slot 331 slides, and a holding plate, which the first thread handling air cylinder 32 holding so that this at the back of the support plate 33 does not fall, and the first thread handling air cylinder 32 is with the support plate 33 connected to perform a forward and backward movement.

The first thread handling air cylinder 32 , which of the support plate 33 is supported is maintained in a state in which the forward / backward movement direction of a piston to the length direction of the yarn handling hook 31 fits, and the forward / backward movement direction of the piston is an obliquely forward-right direction with a right-hand component smaller than that of the long hole 331 ,

The obliquely forwardly rightward movement of the thread handling hook 31 takes place in two steps starting from the outlet position by the first and the second yarn handling air cylinder 32 and 35 ,

The thread handling hook 31 and the bobbin thread, which in 6 are shown with a solid line, the positions in a state in which both the first and the second yarn handling air cylinder 32 and 35 are caused to move forward, and the thread handling hook 31 and the lower thread, which are indicated by a two-dot long-dashed line, show the positions in a state in which in the state in which both the first and the second yarn handling air cylinder 32 and 35 are caused to move forward, only the second thread handling air cylinder 35 is caused to a backward movement.

By the thread handling hook 31 is caused to move furthest forward, its tip gets into a position where the thread handling hook 31 that of the horizontal boat 18 to the second thread cutting device 70 drooping bobbin thread crosses.

In the state in which both the first and the second yarn handling air cylinders 32 and 35 move forward, only the second thread handling air cylinder 35 is caused to a backward movement, that of the horizontal boat 18 to the second thread cutting device 70 drooping bobbin thread are brought close to the path between the tip of the nozzle 41 the air blowing mechanism 40 and the needle hole 15 runs.

As in 7 shown includes the tip of the thread handling hook 31 a first inclined area 311 formed on the tip thereof to cause the sewing start end of the bobbin thread to move upward, a concave portion 312 formed in the upper part of the tip thereof to catch the sewing start end of the lower thread, a second inclined portion 313 , which at the rear end (opposite the top) inside the concave area 312 is formed to cause the Nähstartende of the lower thread to a downward movement, and a third inclined portion 314 which is the second inclined area 313 inside the concave area 312 is facing, and is formed so that the upper end of the second inclined portion 313 is higher than the upper end of the first inclined area 311 ,

The first inclined area 311 has an acute angle, as indicated by an inclination angle θ1, is inclined upward and can the lower thread, at the time of forward movement of the thread-handling hook 31 with the first inclined area 311 comes in contact, push up.

The second inclined area 313 has an obtuse angle, as indicated by an inclination angle θ2, and is inclined downwardly, and the upper end of the second inclined portion 313 is higher than the upper end of the first inclined portion 311 , Accordingly, it is at the time of advancing the thread handling hook 31 possible, from the first inclined area 311 pushed up bobbin thread in the concave area 312 lower and lead into it.

The third inclined area 314 has an obtuse angle, as indicated by an inclination angle θ3, and is inclined downwards, and its upper end has the same height as the first inclined portion 311 , Accordingly, it is at the time of the backward movement of the thread handling hook 31 possible in the concave area 312 to catch it in bobbin thread, and to prevent the bobbin thread unintentionally from the concave area 312 comes out.

By using this structure, the thread handling hook can 31 the lower thread in contact with the first inclined area 311 bring and the bobbin thread by forward movement of the thread handling hook 31 slide up and over the second inclined area 313 catch the lower thread and into the concave area 312 lead in like in 7A shown when the lower thread is arranged lower than the upper end of the first inclined portion 311 , When the thread handling hook 31 is caused to perform a backward movement, the lower thread is in the concave area 312 through the third inclined area 314 caught and kept out of the concave area 312 to get out. The lower thread in the concave area 312 is blown up by the air blowing mechanism to be described later, but at this time moves along the third inclined portion 314 , whereby the movement is not disturbed.

When the lower thread is disposed at a position higher than the upper end of the first inclined portion 311 but lower than the upper end of the second inclined area 313 , then the lower thread can by a forward movement of the thread handling hook 31 in direct contact with the second inclined area 313 brought and into the concave area 312 be guided into, as in 7B shown. The behavior of the lower thread at the time of the backward movement of the thread handling hook 31 is the same as in 7A shown.

air blow

8th FIG. 15 is a perspective view showing a state in which the nozzle. FIG 41 the air blowing mechanism 40 moves backwards, and 9 FIG. 15 is a perspective view showing a state in which the nozzle. FIG 41 the air blowing mechanism 40 moved forward.

As shown in the figures, the air blowing mechanism comprises 40 a nozzle 41 from whose tip air from a position below the needle hole 15 to the needle hole 15 is discharged, a nozzle holding area 43 which is the nozzle 41 releasably holds and is connected to an air supply source (for example, with a compressor), a Düsenhubluftzylinder 44 , the nozzle 41 over the nozzle holding area 43 causes a forward and backward movement, and a switching valve 45 (please refer 3 ), which controls the supply and interruption of air from the air supply source to the nozzle holding area 43 on.

The nozzle holding area 43 includes a tubular nozzle insertion area 431 and a frame area 432 , which is the nozzle introduction area 431 with the piston of the nozzle air cylinder 44 combines.

The nozzle insertion area 431 can the nozzle 41 insert in it and the nozzle 41 fix it with a screw. By loosening the screw, the nozzle can 41 be easily removed, and in place of a flat nozzle 41 can also have a ring nozzle 42 occur, which will be described later.

The nozzle holding area 43 is connected to an air supply hose and allows through the supplied air, the discharge of air from the tip of the nozzle 41 ,

That of the nozzle holding area 43 held nozzle 41 is directed diagonally up to the front. The piston of the nozzle lift air cylinder 44 can the nozzle 41 to a forward and backward movement in the same direction as the length direction of the nozzle 41 cause. As in 9 can be shown in the state in which the piston of the nozzle air cylinder 44 makes a forward movement, the tip of the nozzle 41 be brought into a position which is almost just below the needle hole 15 lies.

As in the 10 and 11 shown points the nozzle 41 a flat opening that extends substantially along the right-left direction and can push out and blow out air at a high speed. Center in the width direction of the tip of the nozzle 41 is a slot 411 formed at the time of forward movement of the nozzle 41 can absorb the sewing start end of the lower thread. That is, the air blowing mechanism 40 is arranged such that the sewing start end of the bobbin thread which is close to the thread handling hook 31 the thread handling mechanism 30 is brought, at the time of forward movement of the nozzle 41 in the slot 411 is recorded.

In place of the nozzle 41 can the ring nozzle 42 kick in which 12 and 13 is shown. The ring nozzle 42 has a slot 421 which is formed at its tip to receive the lower thread therein.

The ring nozzle 42 has a wider opening and thus can blow out air in a wider area.

Holding release mechanism

As in the 4 and 8th includes the hold release mechanism 20 a locking member 21 which is the leaf spring 73 the second thread cutting device 70 and a release air cylinder 22 who is the locking member 21 raises and lowers.

The locking member 21 is arranged in the vertical direction and its upper end is bent perpendicularly to the right. The curved area 211 the upper end of the locking member 21 is adapted to the surface of an intermediate region in the longitudinal direction of the leaf spring 73 to be arranged facing from above.

The release air cylinder 22 can the locking member 21 in which the curved area 211 located in the position which the upper surface of the leaf spring 73 tightly, driving to a downward movement and can the leaf spring 73 over the locking member 21 pull down.

This downward pull turns the tip of the leaf spring 73 from the movable knife 71 separated and gives that between the movable knife 71 and the leaf spring clamped seam start end of the bobbin thread free.

needle plate

14 is a top view of the throat plate 17 , The throat plate 17 is a rectangular flat plate which is formed horizontally on the upper surface of the sewing bed 16 to be mounted, and which is arranged such that the direction of the long side is parallel to the front-rear direction.

A rectangular opening 171 through which the transporter 14 emerges or recedes, is in the middle of the upper surface of the throat plate 17 trained, and starting from the opening 171 is an opening 172 in which the movable knife 61 and the solid knife 62 the first thread cutting device 60 and the thread-pulling member 81 are arranged, formed continuously. The opening and the aperture are formed, the throat plate 17 to enforce vertically.

At the front of the opening 171 is starting from the opening 171 a guide groove 173 the sliding plate 51 of the sewing start holding mechanism 50 , which will be described later, formed continuously. The guide groove 173 has the same lateral width as the opening 171 ,

Nähstartendehaltemechanismus

The sewing start holding mechanism 50 includes a sliding plate 51 (please refer 15 to 20 ), at which a first opening 511 and a second opening 512 as a top thread catch hole and a Underneath thread hole are formed for holding Nähstartenden an upper thread and a lower thread, a first thread-holding air cylinder 52 , which is the sliding plate 51 causes a forward and backward movement, and a second yarn-holding air cylinder 53 (please refer 3 ), which the sliding plate 51 and the first thread-holding air cylinder 52 causes a forward and backward movement.

The sliding plate 51 is a long flat plate which extends in a straight line and in the front-rear direction in the guide groove 173 the needle plate 17 is arranged. The first opening 511 which holds the sewing start end of the upper thread is formed, the rear end of the slide plate 51 to enforce, and the second opening 512 which holds the sewing start end of the lower thread is adapted to pass through the position which is slightly forward with respect to the rear end.

The sliding plate 51 positions the first or the second opening 511 or 512 immediately above the needle hole 15 by forward and backward movement, and clamps and holds the sewing start end of the lower thread D or the upper thread U between the lower surface of the slide plate 51 and the inner surface of the guide groove 173 the needle plate 17 by advancing after introduction of the sewing start end of the lower thread or the upper thread into the same.

The sliding plate 51 happens the sewing start end of the lower thread D, which of the air blowing mechanism 40 at a lower thread insertion position, at which the second opening 512 relative to the pinhole 15 is positioned ( 16 ) is blown upwards, and moves from this state to an upper thread insertion position at which the first opening 511 relative to the pinhole 15 is positioned ( 19 ). In the upper thread insertion position, the sewing start end of the lower thread D becomes between the sliding plate 51 and the throat plate 17 clamped and held, and the sewing start end of the upper thread U can be inserted therethrough. After insertion of the upper thread U through the opening, the sliding plate moves 51 further forward to the run-out position, and the sewing start ends of the lower thread D and the upper thread U are between the slide plate 51 and the throat plate 17 held ( 20 ).

Accordingly, the sliding plate must 51 Position three positions: the lower thread insertion position, the upper thread insertion position and the outlet position.

At the first thread holding air cylinder 52 is the sliding plate 51 connected directly to the piston of the same, and it causes the sliding plate 51 moved between the lower thread insertion position and the upper thread insertion position.

In the second thread holding air cylinder 53 is the body of the first thread-holding air cylinder 52 connected directly to the piston of the same, and it causes the sliding plate 51 and the first thread-holding air cylinder 52 move between the upper thread insertion position and the run-out position.

The first thread holding air cylinder 52 can in the sewing bed 16 be supported by a sliding in the front-rear direction sliding guide or the like.

First thread cutting device

21 is a perspective view of the first thread cutting device 60 . 22 to 24 are perspective views of the movable blade 61 and the solid knife 62 the first thread cutting device 60 ,

The first thread cutter 60 includes a movable knife 61 which is long in the right-left direction and has a right-hand edge at its right end, a fixed knife 62 which is long in the right-left direction and which has a hook-shaped portion at its right end 621 and a first thread cutting air cylinder 63 (please refer 3 ), which is the movable knife 61 caused a reciprocation in the right-left direction.

The moving knife 61 has an edge at the tip, which is flat in the front-to-back direction and the fixed knife 62 is superimposed. The base end of the moving knife 61 is on a support plate 64 fixed, which on the piston of the first thread cutting air cylinder 63 is appropriate.

The moving knife 61 is at the time of non-cutting on the left side of the slide plate 51 arranged and the solid knife 62 is in the breakthrough 172 the needle plate 17 arranged, and at the time of cutting, it moves to the right and moves under the slide plate 51 ,

The solid knife 62 has a left-facing edge, which is inside the hook-shaped area 621 is formed at the right end of the same, and clamps and cuts the lower thread and the upper thread, which in the hook-shaped area 621 run in, between the edge of the fixed knife 62 and the edge of the movable knife 61 ,

The solid knife 62 extends to the right of the movable blade at the time of non-cutting 61 and is arranged to the slide plate 51 to go under.

Thread pulling mechanism

As in 22 to 25 shown includes the thread pulling mechanism 80 a thread-pulling link 81 passing through the sliding plate 51 stopped sewing start ends of the bobbin thread D and the upper thread U and pulls the caught sewing start ends down, and a thread drawing air cylinder 82 (please refer 3 ), which the thread-pulling link 81 caused to move in a predetermined thread pulling direction.

The thread-pulling link 81 includes a holding area 811 , which presses the Nähstartenden the bobbin thread D and the upper thread U from above, a claw area 812 , which at the top (at the right end) of the holding area 811 bent down and holds the sewing start ends of the lower thread D and the upper thread U, not to the holding area 811 to deviate, and a continuation area 813 that is different from the holding area 811 from in the thread-pulling direction (in the obliquely downward-left direction), and the base end of the extension portion 813 is with the piston of the thread drawing cylinder 82 connected.

The tip of the thread-pulling link 81 is arranged, the immediate front of the fixed knife 62 the first thread cutting device 60 to be adjacent. The thread-pulling link 81 is through the holding area 811 , the claw area 812 and the extension area 813 is formed substantially U-shaped and is arranged to cause the sliding plate to a the inside of the U-shape passing movement. So if the sliding plate 51 moves to the front run-out position and holds the sewing start ends of the lower thread D and the upper thread U, the sewing start ends of the lower thread D and the upper thread U pass through the inside of the U-shape.

At this time, since the sewing start ends of the lower thread D and the upper thread U are on the right side of the hook-shaped portion 621 the solid knife 62 are arranged as in 22 shown, the sewing start ends are not cut in this state.

However, since the thread-pulling member 81 through the thread drawing air cylinder 82 moved obliquely down to the left, as in 25 2, the sewing start ends of the lower thread D and the upper thread U can be made to be in the hook-shaped portion 621 the solid knife 62 be pulled in to engage with this.

Accordingly, the sewing start ends of the lower thread D and the upper thread U can be cut by the movable knife 61 is caused to a left-directed movement.

catch mechanism

The catch mechanism 19 is inside the sewing bed 16 and below the first thread cutting device 60 arranged. The catch mechanism 19 For example, a housing whose top is open includes a fan 191 (please refer 3 ), which is disposed in the housing, and a trap which catches the cut pieces of the lower thread and the upper thread sucked into the housing, and can trap the cut pieces in the case by driving the blower 191 to catch.

Control system of the sewing machine

A control system of the sewing machine will be described below with reference to FIG 3 described.

Coarsely comprises a control device 110 the sewing machine 10 a ROM 112 in which various programs for various processes, such as control and determination processes, are stored, a CPU 111 performing various computing processes according to various programs, a RAM 113 which is used as memory in various processes, and an EEPROM 114 in which a variety of sewing data and setting data are stored.

About a system bus, a drive circuit and the like is the control device 110 connected to the sewing motor 117 serving as a driving source for sewing, the release air cylinder 22 the hold release mechanism 20 , the first thread handling air cylinder 32 and the second yarn handling air cylinder 35 the thread handling mechanism 30 , the nozzle lift air cylinder 44 and the switching valve 45 the air blowing mechanism 40 , the first thread-holding air cylinder 52 and the second thread-holding air cylinder 53 of the sewing start holding mechanism 50 , the first thread cutting air cylinder 63 the first thread cutting device 60 , the second thread cutting solenoid 74 the second thread cutting device 70 , the thread drawing cylinder 82 of the thread pulling mechanism 80 , the blower 191 the catch mechanism 19 , an operation input unit 115 , which is used to input various operations, and a start pedal 116 , which is used to enter the sewing start.

In fact, the controller controls 110 Solenoid valves via which the release air cylinder 22 , the first thread handling air cylinder 32 , the second thread handling air cylinder 35 , the nozzle lift air cylinder 44 , the first thread-holding air cylinder 52 , the second thread-holding air cylinder 53 , the first thread cutting air cylinder 63 , the second thread cutter solenoid 74 and the Thread pulling air cylinder 82 be activated individually; However, the solenoid valves are not shown here.

The sewing motor 117 and the fan 191 are controlled by the drive circuit, but are also not shown here.

Cutting control of the sewing start end

30 FIG. 10 is a flowchart showing a control procedure for cutting the sewing start ends of the lower thread D and the upper thread U. The control procedure for cutting the sewing start ends of the lower thread D and the upper thread U, which by the above-mentioned configuration having control means 110 the sewing machine 10 is carried out at the time of sewing start, will be described below mainly with reference to the perspective views of 15 to 20 , the operation diagrams of 26 to 29 and the flowchart of 30 described. In 26 to 29 a reference character C denotes a sewing material as a sewing target.

The operation of cutting the sewing start ends, which will be described below, is based on the assumption that the sewing motor 117 is first stopped, in a state in which the needle bar is located at top dead center, and that the tip of the lower thread by the preceding sewing operation by the second thread cutting device 70 is clamped. The sliding plate 51 is in the discharge position ( 26A ), when the power supply of the sewing machine is turned off, and the slide plate 51 moves into the lower thread insertion position ( 26B ) when the power of the sewing machine is turned on. In the following description, the state in which the sliding plate is described 51 moves to the lower thread insertion position when the power of the sewing machine is turned on.

In the state in which the first and the second thread-holding air cylinder 52 and 53 perform a forward movement, the sliding plate 51 arranged at the Spulenfadeneinführposition, wherein the second opening 512 the needle hole 15 is superimposed (step S1 in 30 ). At this time, the thread-pulling air cylinder is 82 arranged in the forward moving position and the thread pulling member 81 is above the sliding plate 51 arranged ( 15 ).

As in 4 is shown with respect to the sewing start end of the lower thread, which from the horizontal boat 18 to the second thread cutting device 70 Hangs, the thread handling hook 31 caused to perform a forward movement in the state in which the first and the second yarn handling air cylinder 32 and 35 the thread handling mechanism 30 , Accordingly, the sewing start end of the bobbin thread becomes in the concave area 312 and then only the second thread handling air cylinder 35 causes a backward movement. Accordingly, the lower thread is continuously from the horizontal boat 18 led out and pulled, such that the sewing start end of the bobbin thread just below the needle hole 15 hindurchpassiert.

Subsequently, the nozzle lift air cylinder 44 the air blowing mechanism 40 causes a forward movement to the nozzle 41 raise, and the tip of the nozzle 41 approaches the bobbin thread and the pinhole 15 ,

By the release air cylinder 22 the hold release mechanism 20 is caused to a backward movement to the locking member 21 is lowered, the holding state of the sewing start end of the bobbin thread by the second thread cutting device 70 Approved. The switching valve 45 the air blowing mechanism 40 is controlled in an air supply state. As a result, by blowing air, the sewing start end of the bobbin thread D from the position below the needle hole 15 up to a position above the needle hole 15 blown and through the needle hole 15 and the second opening 512 introduced ( 16 and 26B and step S5 in FIG 30 ).

Subsequently, the first thread holding air cylinder 52 causes a backward movement, and the slide plate 51 is caused to move to the upper thread insertion position at which the first opening 511 the needle hole 15 is superimposed ( 17 and 26C and step S7 in 30 ). Accordingly, the sewing start end of the bobbin thread D becomes between the slide plate 51 and the throat plate 17 clamped. At this time, the Düsenhubluftzylinder 44 causes a backward movement to the nozzle 41 lower.

Then the sewing motor 117 driven to start a sewing process ( 18 and step S9 in FIG 30 ).

Accordingly, the sewing needle 11 lowered to perform the stitch point of a first stitch, the upper thread U enters the first opening 511 and into the needle hole 15 one, the edge of the horizontal boat 18 , which with drive of the sewing motor 117 begins to rotate is raised and the sewing start end of the upper thread U is in a position below the needle hole 15 drawn ( 19 and 27A ).

Subsequently, the second yarn holding air cylinder 53 to a backward movement, at the timing at which the sewing needle 11 is lifted and from the needle hole 15 deviates, and the sliding plate 51 is caused to move to the exit position ( 20 and 27B and step S11 in FIG 30 ).

Accordingly, the sewing start ends of the lower thread D and the upper thread U are pulled forward and extend below the thread pulling member 81 forward and backward.

The thread draw air cylinder 82 is caused to move backwards to the thread pulling member 81 lower ( 27C and step S13 in FIG 30 ).

Accordingly, as in 23 are shown, the Nähstartenden of the lower thread D and the upper thread U by means of the thread-pulling member 81 trapped and down into the hook-shaped area 621 the solid knife 62 the first thread cutting device 60 pulled into it.

Needle handling by the sewing motor 117 is performed continuously, and the stitch point of a second stitch is executed ( 28A ).

At this time, the thread-pulling air cylinder stops 82 the backward moved state, and by means of the thread-pulling member 81 a downward pulling force is continuously exerted on the sewing start ends of the lower thread D and the upper thread U. Accordingly, with the progress of sewing and forward transport of the cloth C, an additional length of the lower thread D and the upper thread U is generated, the thread pulling member 81 will be lowered by the same amount ( 28B ) and the sewing start ends of the lower thread D and the upper thread U are further in the hook-shaped portion 621 the solid knife 62 pulled into it.

In the meantime, the controller monitors 110 continuously the position of the needle bar based on the drive of the sewing motor 117 and wait for the needle high gear timing of a third stitch (step S15 in FIG 30 ).

Upon reaching the needle high gear timing of the third stitch, the stitch point position of the first stitch is immediately above the thread trimming position of the first thread trimmer 60 , This timing is achieved by switching the first thread cutting air cylinder 63 the first thread cutting device 60 in the forward moving state, the movable knife 61 moved forward to cut the sewing start ends of the lower thread D and the upper thread U ( 24 and 28C and step S17 in FIG 30 ).

If the sewing start ends of the lower thread D and the upper thread U are cut at this timing, then the sewing start end of the upper thread U can be cut shortest. Since no knot is formed in the first stitch, the lower thread D is hanging down from the stitch point position of the second stitch, but the sewing start end of the lower thread D can be satisfactorily shortened.

If it is preferable to shorten the sewing start end of the lower thread D, then the thread cutting may be performed at the sewing needle high gear timing of a fourth stitch.

Subsequently, after sewing, the first and the second thread holding air cylinder become 52 and 53 switched to the forward moving state and the sliding plate 51 is caused to move to the lower thread insertion position at which the second opening 512 the needle hole 15 is superimposed ( 29 and step S19 in FIG 30 ). At the same time the blower 191 the catch mechanism 19 activated (step S21 in 30 ).

Accordingly, the cut pieces of the lower thread D and the upper thread U passing through the sliding plate 51 be held, released and dropped and by the catching mechanism 19 captured.

Accordingly, the control process for cutting the sewing start ends of the lower thread D and the upper thread U ends.

Technical advantages of the embodiment

The sewing machine 10 includes the lower thread insertion mechanism 2 which introduces a sewing start end of a bobbin thread D from the lower side into the needle hole, the Nähstartendehaltemechanismus 50 which is in the needle hole 15 introduced sewing start end of the bobbin thread D above the throat plate 17 stops, and the first thread trimmer 60 that by the Nähstartendehaltemechanismus 50 held sewing start end of the lower thread D cuts.

Accordingly, it is possible to cut the sewing start end of the lower thread D remaining in the cloth C to make it shorter and thereby improve the sewing quality.

The sewing machine 10 includes the second thread cutting device 70 which cuts the lower thread D consumed in sewing and holds the end of the cut lower thread D on the shuttle side as the sewing start end for the next sewing, and the lower thread insertion mechanism 2 includes the hold release mechanism 20 which detects the clamped state of the sewing start end of the Lower thread D through the second thread cutting device 70 releases the thread handling mechanism 30 which the sewing start end of the bobbin thread D to the bottom of the needle hole 15 pulls, and the air blower mechanism 40 which feeds the sewing start end of the bobbin thread D, the clamped state of which is released, into the needle hole by air 15 introduces.

Accordingly, at the sewing end, the tail of the lower thread D on the shuttle side can be clamped as a sewing start end for the next sewing operation. Through the interaction of holding release mechanism 20 , Thread handling mechanism 30 and air blowing mechanism 40 it is possible to automatically introduce the sewing start end of the lower thread D into the needle hole.

Moreover, it is characterized by being up in the needle hole 15 introduced sewing start end of the lower thread D by the Nähstartendehaltemechanismus 50 held and by the first thread cutter 60 it is possible to automatically perform a series of operations, thus realizing a reduction in workload and an improvement in work efficiency.

The thread handling mechanism 30 the sewing machine 10 includes the thread handling hook 31 advancing the sewing start end of the bobbin thread D close to the bottom of the needle hole 15 the thread handling hook 31 includes the first inclined area 311 formed at its tip to cause the sewing start end of the bobbin thread D to move upward, the concave portion 312 formed on top of the tip to catch the sewing start end of the bobbin thread D and the second inclined portion 313 in the interior of the concave area 312 is formed to cause the Nähstartende the bobbin thread D to a downward movement, and the upper end of the second inclined portion 313 is designed to be set higher than the upper end of the first inclined portion 311 ,

Accordingly, the vertical range in which the sewing start end of the bobbin thread D by the thread handling hook 31 can be set wider, and it is thus possible, the lower thread D more reliable to the bottom of the needle hole 15 respectively.

The air blowing mechanism 40 the sewing machine 10 includes the nozzle 41 or 42 which air to the pinhole 15 out, and the nozzle 41 or 42 includes the slot 411 or 412 at the top of which the sewing start end of the bobbin thread D is inserted.

Accordingly, it is by the sewing start end of the bobbin thread D at the time of raising the nozzle 41 or 42 in the slot 411 or 421 guided and held therein, possible, the Nähstartende the bobbin thread D more reliable in the needle hole 15 blow up and introduce into this.

The sewing start holding mechanism 50 the sewing machine 10 includes a sliding plate 51 in which the first opening 511 and the second opening 512 are arranged in the sliding direction. Accordingly, the sewing start end of the bobbin thread D between the facing surfaces of the slide plate 51 and the throat plate 17 clamped and held by the sliding plate to a sliding movement starting from the lower thread insertion position at which the second opening 512 the needle hole 15 is superimposed, and the sewing start ends of the lower thread D and the upper thread U can between the mutually facing surfaces of the sliding plate 51 and the throat plate 17 clamped and held by the sliding plate to a sliding movement starting from the upper thread insertion position at which the first opening 511 the needle hole 15 is superimposed.

Accordingly, it is possible to hold both the sewing start end of the lower thread D and the sewing start end of the upper thread U using a single member to achieve a reduction in the number of components and to realize size reduction of the mechanisms and space saving.

At the sewing machine 10 slides the sliding plate 51 downstream in the transport direction of the transporter 14 which constitutes the cloth feeding mechanism for holding the sewing start ends of the upper thread U and the lower thread D, and the first thread cutting device 60 is with respect to the pinhole 15 downstream in the transport direction of the transporter 14 arranged the transport mechanism.

The control device 110 controls the Nähstartendehaltemechanismus 50 to hold the sewing start end of the bobbin thread D before the stitch point of the first stitch, and to keep the sewing start end of the upper thread U after the stitch point of the second stitch, and controls the first thread cutting device 60 to cut the sewing start ends of the upper thread and the lower thread after the stitch point of the second stitch.

Accordingly, since the base portions of the sewing start ends of the lower thread D and the upper thread U which hang down from the sewing cloth are close to the first thread cutting means arranged downstream in the cloth conveying direction 60 a further reduction of the sewing start ends of the lower thread and the upper thread, which remain in the fabric after cutting, possible.

At the sewing machine 10 are the moving knife 61 and the solid knife 62 the first thread cutting device 60 below the sliding plate 51 arranged, and it is the thread pulling mechanism 80 provided, which the Nähstartenden of the upper thread U and the lower thread D, which passes through the sliding plate 51 to be pulled in sliding direction, pulls down.

Accordingly, it is possible to protect the fabric by the movable knife 61 and the solid knife 62 the first thread cutting device 60 are arranged not to come into scratching or otherwise damaging contact with the fabric, and it is possible, the Nähstartenden of the lower thread D and the upper thread U to the movable blade 61 and the solid knife 62 to guide and thereby perform the cutting reliable.

Another example of the thread pulling mechanism

The thread pulling mechanism 80 pulls the sewing start ends of the lower thread D and the upper thread U using the single thread pulling link 81 to the solid knife 62 the first thread cutting device 60 ; however, two thread-pulling members may be used.

That is, a thread pulling device 80A , what a 31 includes a first thread-pulling member 81A which has a holding area 811A , a claw area 812A and a continuation area 813A includes a second thread-pulling member 83A which has a holding area 831A , a claw area 832A and a continuation area 833A comprises a first thread drawing air cylinder 82A which the second thread-pulling member 83A supports and the holding area 831A of the second thread-pulling member 83A by lifting in press contact with the holding area 811A of the first thread-pulling member 81A brings, and a second thread drawing air cylinder 84A , which is the first thread-pulling member 81A , the second thread-pulling link 83A and the first thread drawing air cylinder 82A supports and lifts them.

In the above-mentioned configuration, by switching the first thread-drawing air cylinder 82A in the forward moving state of the holding area 831A of the second thread-pulling member 83A in press contact with the holding area 811A of the first thread-pulling member 81A and the sewing start ends of the lower thread D and the upper thread U can be clamped therebetween.

By the second thread drawing cylinder 84A in the state in which the sewing start ends of the lower thread D and the upper thread U are clamped, is caused to move backward, it is possible to cause the sewing start ends of the lower thread D and the upper thread U to the knives 61 and 62 the first thread cutting device 60 to draw.

Thus, by clamping and pulling the sewing start ends of the lower thread D and the upper thread U, the sewing start ends of the lower thread and the upper thread can be prevented from being inadvertently caught by the thread pulling members 81A and 83A and the thread-pulling operation can be performed more reliably.

Another example of the sewing start holding mechanism

The sewing start holding mechanism 50 includes the rectilinear sliding plate 51 ; however, the shape is not limited to the straight line shape. For example, as in 32 and 33 shown a Nähstartendehaltemechanismus 50A Use find that an arcuate sliding plate 51A having.

In the sewing start holding mechanism 50A are a first opening 511A and a second opening 512A as the upper thread catching hole and the lower thread catching hole at one end of the arcuate sliding plate 51A formed near the one end, and the Nähstartendehaltemechanismus comprises a first yarn-holding air cylinder 52A which has an input arm 54A that the sliding plate 51A supports, in a rotational movement offset, such that it is rotatable about the center of the arc and coaxial with the sliding plate 51A rotates, and a second thread-holding air cylinder 53A , which the first thread-holding air cylinder 52A to a forward and backward movement in the same direction as the direction of movement of the piston of the first yarn-holding air cylinder 52A causes.

In this case, the sliding plate 51A arranged so that the needle hole 15 located on the circumference of the arc of the sliding plate 51A includes, and the input arm 54A and the piston of the first thread holding air cylinder 52A are connected by a shaft and a slot, slid over the arch and interlock.

The elements are arranged such that the second opening 512A the sliding plate 51A the needle hole 15 superimposed when both the first thread-holding air cylinder 52A as well as the second thread-holding air cylinder 53A in the forward moving state are that the first opening 511A the needle hole 15 superimposed when one of the two elements, which are the first thread holding air cylinder 52A and the second yarn holding air cylinder 53A , is in the forward moving state, and that the openings are arranged in the discharge position, in which the entire sliding plate 51A from the needle hole 15 deviates when both the first thread-holding air cylinder 52A as well as the second thread-holding air cylinder 53A are in the backward moving state.

Accordingly, the Nähstartendehaltemechanismus 50A the sliding plate 51A in the insertion position of the sewing start end of the lower thread D, in the insertion position of the sewing start end of the upper thread U and in the run-out position by the thread holding air cylinder 52A and 53A be controlled in the same manner as in the Nähstartendehaltemechanismus 50 ,

When the slide plate has a rectilinear shape, the arrangement space should be for the slide plate 51 in front of the needle hole 15 to be widely assured; if the sliding plate 51A however, has an arcuate shape, then the arrangement space in front of the needle hole 15 be reduced, and thus it is possible to achieve a space saving.

Regulator plate of the thread pulling link

When using the sliding plate 51A with an arcuate shape, the openings move 511A and 512A along the arch, as in 34 shown. Accordingly, at the time of holding the sewing start end, the sewing start end of the lower thread D or the upper thread U deviates in the right-left direction (to the left when the sliding plate 51A curved to the left, as in 34 shown) from the front-to-back direction and is pulled.

Because the sliding plate 51A is curved, the sliding plate can 51A not through the interior of the holding area 811 of the thread-pulling member 81 if not the width of the holding area 811 is designed to be larger than the width of the sliding plate 51A ,

Further, the sewing start end of the lower thread D or the upper thread U comes too close to the ends of the holding portion 811 of the thread-pulling member 81 in the right-left direction, and thus there is a possibility that the sewing start end of the lower thread D or the upper thread U does not properly enter the hook-shaped area 621 is guided into, even if the thread-pulling member 81 moved in a given direction.

So if the sliding plate 51A is used with an arcuate shape, it is preferred if Regulierplatten 85A and 86A which regulate the sewing start ends of the lower thread and the upper thread so that they do not move further in the right-left direction than the width of the slide plate 51A , on one side in the front-to-back direction of the thread pulling member 81 are formed.

It is preferable if an inclination 851A in the regulating plate 85A is formed, which on an inner diameter side in the direction of curvature of the sliding plate 51A is arranged such that the sewing start ends of the lower thread D and the upper thread U does not fall down. On the outer diameter side, the sewing start ends of the lower thread D and the upper thread U do not gather well, and thus the regulating plate can 86A may be omitted on the outside diameter side.

Another example of the holding mechanism

The curved area 211 the upper portion of the locking member 21 may be adapted to the underside of an intermediate region in the length direction of the leaf spring 73 to approach from below and to face it.

In this configuration, the leaf spring is supported 73 in a condition in which the leaf spring from the bottom of the movable knife 71 is disconnected, if no external force is applied, the release air cylinder 22 drives the locking member 21 , which is arranged in the position in which the curved portion 211 the lower surface of the leaf spring 73 approximates and this is facing to move upwards, and pushes the leaf spring 73 over the locking member 21 up. This push-up pushes the tip of the leaf spring 73 against the moving knife 71 and holds the sewing start end of the lower thread in cooperation with the movable knife 71 in the clamped state.

When releasing the holding state of the lower thread, the pressing action of the locking member 21 on the leaf spring 73 be canceled by driving the release air cylinder 22 to the locking member 21 lower and separate from it.

additional

The sewing machine 10 is exemplified as a sewing machine with mechanical feed; however, the elements for holding and cutting sewing start ends of a lower thread and an upper thread may be applied to another sewing machine (for example, a lockstitch sewing machine) in which a needle bar does not vibrate.

By way of example, the case was shown that the needle hole 15 in the transporter 14 is trained; However, the present invention is not limited to this case, and the members for holding and cutting the sewing start ends of a lower thread and a upper thread may also be applied to a sewing machine in which the needle hole is formed in the throat plate.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2006-320365 A [0005]

Claims (8)

Sewing machine with a needle hole formed in a needle plate or in a feed dog, comprising: a bobbin thread insertion mechanism that includes an air blowing mechanism that introduces a sewing start end of a bobbin thread from an underside of the needle plate into the needle hole by air; a Nähstartendehaltemechanismus which holds the Nähstartende the inserted lower thread above the throat plate; a first thread cutting device which cuts the sewing start end of the lower thread held by the sewing start stop holding mechanism; and a controller that controls operations of the sewing machine. Sewing machine according to claim 1, wherein the air blowing mechanism comprises a nozzle which discharges air toward the needle hole, wherein the nozzle has a slot at a tip of the nozzle and wherein the slot is adapted to guide and hold the sewing start end of the lower thread. Sewing machine according to claim 1 or 2, the sewing start stopping mechanism comprising a slide plate having a top thread catching hole and a bottom thread catching hole, wherein the upper thread catching hole and the lower thread catching hole are arranged in a sliding direction, wherein the upper thread catching hole and the lower thread catching hole are formed to clamp and hold the sewing start end of the lower thread and a sewing start end of an upper thread between the sliding plate and a facing surface of the throat plate, wherein the slide plate is movable to an upper thread insertion position, a lower thread insertion position, and a run-out position, wherein in the upper thread insertion position, the upper thread catching hole is superimposed on the needle hole, wherein in the lower thread insertion position, the lower thread catching hole is superimposed on the needle hole, and wherein in the discharge position, both the lower thread catching hole and the upper thread catching hole are separated from the pinhole. Sewing machine according to claim 3, wherein the slide plate clamps and holds the sewing start end of the upper thread and the sewing start end of the lower thread between the slide plate and the facing surface of the throat plate in the run-out position and wherein the control means controls the sewing machine to: before a stitch point of a first stitch to arrange the slide plate in the lower thread insertion position, to introduce the sewing start end of the lower thread from the lower side into the needle hole and the lower thread catch hole by using the air blowing mechanism after the sewing start end of the lower thread To arrange the slide plate in the upper thread insertion position, to insert the sewing start end of the upper thread into the needle hole and the upper thread catch hole by the stitch point of the first stitch, place the slide plate in the run-out position after introduction of the sewing start end of the upper thread and the sewing start end of the upper thread at a stitch point of a second stitch and to cut the sewing start end of the lower thread by using the first thread cutting device. Sewing machine according to claim 3 or 4, wherein a knife of the first thread cutting device is arranged below the sliding plate, the sewing machine further comprising: a thread pulling mechanism that performs a downward movement when the slide plate is disposed in the run-out position, the sewing start end of the upper thread and the sewing start end of the lower thread pulled out by the slide plate pulls and the sewing start end of the upper thread and the sewing start end of the lower thread with the first thread cutting device Engages, and wherein the control means controls the sewing machine to cut, after downward movement of the thread pulling mechanism, the sewing start end of the upper thread and the sewing start end of the lower thread by using the first thread cutting device. Sewing machine according to one of claims 3 to 5, further comprising: a second thread cutting device which cuts the lower thread upon completion of a first sewing operation and holds an end of the cut lower thread on a shuttle side as a sewing start end for a second sewing operation next following the first sewing; wherein the bobbin thread insertion mechanism comprises: a holding release mechanism which releases a holding state of the sewing start end of the lower thread held by the second thread cutting device, and a thread handling mechanism which pulls the sewing start end of the lower thread to the lower side of the needle hole. The sewing machine according to claim 6, wherein the thread handling mechanism comprises a thread handling member which pulls the sewing start end of the lower thread to the lower side of the needle hole by forward movement of the thread handling member, the thread handling member comprising a first inclined portion, a concave portion, and a second inclined portion. wherein the first inclined portion is formed at a tip of the thread handling member to move up the sewing start end of the lower thread, the concave portion being formed in an upper part of the tip to catch the sewing start end of the lower thread, the second inclined portion inside of the concave portion is formed to move down the sewing start end of the lower thread, and wherein an upper end of the second inclined portion is higher than an upper end of the first inclined portion. The sewing machine according to claim 6 or 7, wherein before the introduction of the sewing start end of the lower thread into the needle hole and the lower thread catch hole by using the air blowing mechanism, the control means controls the sewing machine to drive the thread handling mechanism, pull the sewing start end of the lower thread to the lower side of the needle hole, and to drive the holding release mechanism to release the holding state of the sewing start end of the lower thread held by the second thread cutting device.

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