TWI650460B - Double loop stitching method and double loop stitching sewing machine - Google Patents

Abstract

The needle loop formed by the needle thread under the needle plate is self-connected to prevent the double loop stitching seam from spreading, and then driven by the movable cutter to cut the needle thread portion protruding on the back side of the sewing fabric at or near the needle drop position. In addition, the thread hooking portion protruding on the back side of the sewing fabric is moved to the edge portion of the fixed cutter in a range that does not enter the up and down motion path of the needle, and the sliding edge of the blade edge portion and the thread hook thread catching portion causes Was cut off. Accordingly, the present invention provides a double-loop sewing method and a sewing machine which can improve the sewing operation efficiency without the need for steps such as reinforcement stitching and thread cutting operations such as scissors, and can cut the threads protruding on the back side of the sewing fabric as appropriate. The appropriate length will not decrease the anti-scratch effect and improve the appearance of the sewn product.

Description

Double-loop sewing method and double-loop sewing machine

The invention relates to a double-loop stitching method and a double-loop stitching sewing machine, which mainly uses a double-loop stitching sewing machine represented by a horizontal cylinder shape, and forms a double-loop stitching seam by needle thread and thread hook thread, and performs an anti-flapping action. In order to prevent the suture completion part of the double-loop suture seam from flaking.

A general double-cylinder double-loop stitching sewing machine includes: a needle, which keeps the needle thread up and down; and a thread hook, which keeps the thread hook and advances and retreats in a direction slightly orthogonal to the vertical movement path of the needle; The needle repeatedly captures a stitch formed under the needle plate by the movement of the thread hook in and out, and repeatedly loops the needle thread with the thread held by the hook to repeatedly loop the needle thread. , Forming a double loop stitching seam on the sewing fabric.

The structure of a general double-loop suture formed by a double-loop suture sewing machine has the following problems: as shown in FIG. 24, when the sewing is completed in the direction of the arrow shown in FIG. At this time, the hook line 10 is pulled out from the final stitch coils 20a2 and 20b2 formed by the needle lines 20a and 20b. The pull-out of the hook line 10 is easily transferred to the start side of the suture and spreads to the start side of the suture. As a result, The entire sewing seam M is open.

FIG. 24 shows a double loop suture M formed by two needle threads 20a, 20b and a hook line 10. However, for a double loop suture formed by a needle thread and a hook line, the same hook as described above also occurs. line.

The present applicant has developed a method of preventing blooming as shown in Japanese Patent Application Laid-Open No. 2011-206527 and Japanese Patent Application Laid-Open No. 2013-6009 for the purpose of preventing the puffing peculiar to the sewing seam formed by the double loop sewing machine as described above. And a double-loop stitching sewing machine with an anti-flapping device, and a patent application has been filed (hereinafter, the above-mentioned patent publication is referred to as the prior art invented by the applicant).

As shown in Figs. 25 and 26, the above-mentioned double loop stitch sewing machine of the prior art invented by the present applicant has a needle 2a, 2b (refer to Figs. 16 to 21). The needle threads 20a and 20b (refer to FIGS. 16 to 21) move up and down with respect to the needle drop positions A and A. The needle drop positions A and A are set in the left and right directions at an interval in the center of the needle plate 12; 1 (refer to FIGS. 16 to 21), which can hold the thread hook 10 and advance and retreat in the side-by-side direction of the needle drop positions A and A, and capture the needle coil 20a2 formed under the needle plate 12 when entering and leaving. 20b2; The hook 3 which is curved in an arc shape can move close to and away from the hook 1 in a standby position away from the hook 1 shown in FIG. 25 and close to the hook 1 shown in FIG. 26 Between the thread hanging positions, the support shaft 30 in the upper and lower directions is centered and shakes in a plane slightly parallel to the needle plate 12; the wire hook thread holding body 6 bent in an arc shape is fixed by the fixing screw 60 On the upper surface of the middle part of the hook 3, it is shaken integrally with the hook 3; the wire operating cylinder 32 makes the hook 3 and the wire The thread holding body 6 is driven to swing to the above-mentioned standby position and thread hanging position; the rocking lever 9 and the stop lever 4 are arranged at a position farther away from the needle plate 12 than the thread hanging hook 3, and are supported on the upper surface of the needle plate table 11, and Rotate the support shaft 90 in the up-down direction in a plane that is slightly parallel to the needle plate 12 to keep the needle coils 20a2 and 20b2 captured by the hanging hook 3 at the hanging position between the hanging position and the standby position. A holding cylinder 42 which drives the stop lever 4 from the engaging position engaged with a part of the rocker lever 9 to drive to a retreat position deviating from the engaging position; a connecting rod 35 which is linked to the suspension The wire hook 3 and the rocking lever 9; the return spring 91 Between the post 35 and a spring hook portion 95 protruding forward from the left side of the online operation cylinder 32; and a control unit 8 (refer to FIG. 14) that selectively controls the above-mentioned line operation cylinder 32 and the stopper after the normal sewing is completed Stopping the operation of the air cylinder 42, the needle coil 20b2 captured by the hook portion 3b at the front end of the hook 3 is held at the above-mentioned holding position, and the thread receiving portion 6a at the front end of the hook holder 6 is located at the hook portion The upper side of the thread hook 1 in front of 3b is maintained at this state, and a sewing operation of at least one stitch is performed.

In addition, with respect to the fluff preventing device of the prior art double loop stitch sewing machine invented by the present applicant, the needle plate table 11 is configured as a long object in the left-right direction. The constituent members and constituent parts in the anti-flapping device of the double-loop stitching sewing machine described in the embodiment are the same as or correspond to the corresponding constituent members and constituent parts, and are marked with the same symbols as those explained with the anti-flapping device in the embodiment of the present invention, and are omitted. Detailed description of these components and parts.

According to the above-mentioned prior art invented by the present applicant, after the end of normal sewing, each operation of the thread hook 3, the thread hook holding body 6, the stop lever 4, and the swing lever 9 is controlled by the control unit 8 as described above. As shown in FIG. 27, the thread hook 10 is formed in the final stitch loop 20b2 on the right side (left side in FIG. 27) of the back of the sewing fabric at the end of the double loop stitching seam M, as shown in FIG. To prevent crochet thread 1 stitches from being folded back before the needle thread 20b pulled out on the back side of the sewing fabric, and then cut through the position inside the final needle loop 20b2 on the right side, the result is that the needle thread 20b and the thread hook 10 A knot-like interconnected circle is formed as shown in the figure. On the other hand, the needle thread 20a on the left side (the right side in FIG. 27) pulled out on the back side of the sewing fabric during sewing with one stitch is passed through the final stitch loop 20a2 formed on the back of the sewing fabric at the end of normal sewing. The final needle coil 20a2 is self-looping. With this, since the left self-series The synergistic effect of the loop-shaped and right-side knot-like interconnected loops can prevent the unique hooking of the double loop stitching seam M, regardless of the direction of the force acting on the thread hooking line 10.

As described above, according to the prior art double-loop sewing machine invented by the present applicant, after the normal sewing is completed, the one-needle stitching operation for preventing flaking as described above is continuously performed, whereby the double-loop sewing can be effectively prevented Hooks unique to the stitching. Therefore, it is not necessary to perform other steps such as bar tacking to prevent fracturing after the end of sewing, and it is possible to improve the sewing operation efficiency when continuously producing a large number of sewing products. However, the prior art double loop stitching sewing machine invented by the present applicant still has the following problem: According to the cutting processing method of the needle thread portion and the thread hook portion that protrude on the back side of the sewing fabric after the anti-flapping operation is performed by the tandem loop, The anti-flanging effect caused by self-stringing loops is reduced, or the appearance of the sewn products is deteriorated. This point will be described in detail below.

In the prior art double loop sewing machine invented by the present applicant, as the thread cutting device 5 for cutting the needle thread portion and the thread hook portion protruding on the back side of the sewing fabric, a thread cutting device 5 having the following configuration is used. As shown in FIGS. 28 (A) and 28 (B), the structure includes: a movable cutter 50; a fixed cutter 51; and a hook and wire clamping member 52 made of a flat spring, which are arranged below the movable cutter 50. And elastically clamps the end of the cut wire hook wire 10 between the movable cutter 50 and the above-mentioned movable cutter 50; and a wire clamping auxiliary spring 53 for adjusting the clamping of the wire hook wire clamping member 52 A hook-shaped thread catching portion 50a is formed on a side edge portion of the front end of the movable cutter 50, and a hook-shaped thread catching portion 50b is formed. The hook-shaped thread catching portion 50a is hooked and caught The thread hooking portion 10a protruding from the back side of the sewing fabric W. The hook-shaped needle thread catching portion 50b is sequentially hooked at the side edge portion closer to the base end of the movable cutter 50 than the thread hook thread catching portion 50a. The left and right needle thread portions 20a1 and 20b1 protruding on the back side of the sewing fabric W are captured.

The thread trimming device 5 can be driven back and forth between the entry position P1 toward the front left toward the needle plate 12 and the thread hook 1 and the retreat position P2 toward the rear right from the entry position P1. After the sewing operation is completed, that is, when the stitching is completed, it is driven to move from the retreat position P2 to the in and out position P1, and is linked to the reciprocating drive moving mechanism 70. The reciprocating drive moving mechanism 70 is driven to move to the thread cutting device 5 to After the above-mentioned entry / exit position P1, only the movable cutter 50 is positioned between the side (right side) of the needle drop positions A and A (entry and exit position) and the other side (left side) of the needle drop positions A and A. Drive back and forth between external locations.

In addition, the configuration of the reciprocating drive moving mechanism 70 connected to the thread cutting device 5 in the same manner is the same as the configuration of the reciprocating drive moving mechanism described in detail in the embodiment of the present invention described later. Therefore, the corresponding constituent members are attached with The same symbols are used to describe the reciprocating drive moving mechanism in the embodiment of the present invention.

Next, the thread trimming operation performed by the thread trimming device 5 after the fluff preventing operation as described above is performed by the double loop stitch sewing machine of the prior art invented by the applicant will be described with reference to FIG. 29.

First, as shown in FIG. 29 (a), after the stitching is completed, after the thread cutting device 5 is moved to the external position on the side closer to the needle drop position, that is, the above-mentioned entry / exit position P1, as shown in FIG. 29 (b), only The movable cutter 50 is driven and moved in the direction of the arrow x from the above-mentioned entry / exit position P1 to an outer position on the other side of the needle drop position. By this forward driving movement, as shown in FIG. 29 (c), the thread hook thread catching portion 50a on the front end side of the movable cutter 50 passes over the thread hook between the vicinity of the front end of the hook 1 and the back side of the sewing fabric W. Immediately after the thread 10 is moved, the moving direction of the movable cutter 50 is reversed, and the thread hook thread catching portion 50a is caught and caught by the thread hook thread portion 10a protruding on the back side of the sewing fabric W. Pick up Then, as shown in FIG. 29 (d), the movable cutter 50 moves from the external position on the other side of the needle drop position to the entrance position P1 and drives in the direction of arrow y. When the return drive moves, The left and right needle thread portions 20a1 and 20b1 protruding on the back side of the sewing fabric W are caught and caught by the needle thread catching portion 50b. Next, the movable cutter 50 is further driven and moved in the direction of the arrow y. As a result, as shown in FIG. 29 (e), the needle thread portions 20a1, 20b1 and the thread hook thread capture portion 50b captured by the needle thread capture portion 50b are captured. The thread hooking portion 10 a is cut by the sliding contact of each of the catching portions 50 a and 50 b with the fixed cutter 51. Then, as shown in FIG. 29 (f), the needles 2a and 2b are moved above the needle plate 12, and the ends of the thread hook 10 held by the thread hook 1 are elastically clamped between the movable cutter 50 and the thread hook. Hold between the members 52 for the next sewing.

The thread cutting device of the prior art double loop stitching sewing machine of the present application that performs the thread cutting action as described above is automatically cut off by the sliding contact between the movable cutter 50 and the fixed cutter 51 and protrudes on the back side of the sewing fabric W when sewing is completed. The needle thread portions 20a1, 20b1, and the thread hook portion 10a can cut each thread to a slightly averaged length so that the remaining length of each thread does not vary.

However, in the case of the thread trimmer 5 of the prior art, the cutting positions of the needle thread portions 20a1, 20b1 and the thread hook thread portion 10a are away from the needle drop position so as not to enter the up and down movement path of the needles 2a, 2b. Position, and the outer position on the right side more than the right needle 2b, so as shown in FIG. 27, after cutting, the left and right needle thread portions 20a1, 20b1, and the thread hook portion 10a of the back side of the sewing fabric W are completed. The remaining length of the line counted from the part is still long.

The above-mentioned prior art thread trimming device considers that the cutting position to be cut by sliding contact between the movable cutter 50 and the fixed cutter 51 is as close to the needle drop position as possible, thereby shortening the needle thread portions 20a1, 20b1, and the thread hook. The remaining length of the line after the part 10a is cut, but In this case, after the needle thread portions 20a1 and 20b1 are caught and caught by the needle thread catching portion 50b, the needle thread portions 20a1 and 20b1 are cut to the cutting position where the fixed cutter 51 is located. Therefore, the threads of the needle thread portions 20a1 and 20b1 are cut. There is naturally a limit to the reduction of the remaining length. In particular, the remaining length of the needle thread portion 20a1 on the left side is compared with the remaining thread length of the needle thread portion 20b1 on the right side, and the distance between the left and right needles 2a, 2b is extended. Therefore, the actual situation of the thread trimming device of the prior art is as follows: instead of making the cutting position as close to the needle drop position as possible, as shown in FIG. 12 (B), the cutting edge 51e The position where the vertical movement path of the needle 2b is separated by a sufficient distance d1 is set as the cutting position, whereby each thread reaches a remaining length of the thread suitable for cutting with scissors or the like described later.

In this way, at the completion of sewing, the needle thread portions 20a1, 20b1, and the thread hook portion 10a remain on the back side of the sewing fabric W for a long time. For example, if the sewing object exceeds the sewing object, the aesthetic appearance deteriorates, and the value of the product decreases. Therefore, in order to improve the aesthetic appearance and increase the value of the product, after the stitching is completed, the following means are used: using scissors, etc., to shorten the remaining length of the thread, and manually cut each thread portion on the back side of the sewing fabric W. However, in this case, each time the sewing of a sewing object is completed, the complicated manual operation for cutting the thread is required. As a result, the effect of not only accompanying the anti-flapping action from the tandem loop is halved, that is, no need to reinforce the sewing The other steps, such as anti-scratch operation, increase the efficiency of the sewing operation (increased productivity), halve the effect, and easily damage the sewing fabric W by scissors, etc. In addition, the remaining length of the thread is cut by manual work. It is also prone to deviations. In particular, there is a problem (problem): if the remaining length of the thread is cut too short, the anti-flapping effect of the folded corner will be impaired, and the suture seam after the anti-flapping of the thread is highly likely to open.

The present invention is an invention made in view of the above-mentioned actual situations, and an object thereof is to provide the following double-loop stitching method and double-loop stitching sewing machine. After sewing, it does not require other steps such as reinforcement stitching, nor does it require manual operations such as using scissors. The sewing operation efficiency is significantly improved, and the remaining length of each thread protruding on the back side of the sewing fabric can be cut to an appropriate length. The appropriate length will not reduce the anti-spreading effect caused by the tandem loop, and will not reduce The appearance of the stitched product is deteriorated.

In order to achieve the above-mentioned object, the double-loop suture method of the first invention is a double-loop suture method that captures the needle thread by holding in and out of a thread hook that can advance and retreat in a direction slightly orthogonal to the vertical movement path of the needle. And the needle coil formed by one or more needles under the needle plate is moved up and down, and the needle coils are connected in series by the hook wire held by the hook, and the sewing fabric is conveyed and moved on the needle plate. A double loop suture is formed on the upper loop. The double loop suture method is characterized in that the thread hook is put in and out and the normal sewing is completed, and then a sewing operation including at least one stitch including the following steps is performed. Needle thread to make the above-mentioned needle coil self-connected in series, so as to prevent the double loop stitching seam from spreading. The above-mentioned step refers to keeping the needle loop captured by the hook at a position closer to the entry and exit ends of the hook than the lowered position of the needle, and After the thread of the hook is positioned more forward than the lowered position of the needle, the feeding of the thread of the hook toward the hook is suppressed, and the state is maintained straight. The needle is lowered by the needle coil captured by the thread hook, and then the position holding of the needle coil is released, and the needle is lowered by the needle coil. Then, when the needle drop position in the needle board can be reached A movable cutter that moves back and forth between an external position on one side and a position closer to the other side of the needle drop position. In a backward driving movement between the two positions, the movable cutter moves from the side closer to the needle drop position. When the position is driven toward the external position on the other side, or When the movable cutter moves back from the external position on the other side to the position on the one side, it is cut or pulled near the needle drop position or the vicinity of the needle drop position by the blade formed on the movable cutter. The needle thread portion protruding on the back side of the sewing fabric is dragged and cut; then, when the movable cutter is driven to move from the position on the other side of the needle drop position to the position on the outer side on the one side, it is formed by The thread hook thread catching part of the movable cutter is hooked on the thread hook thread part protruding from the back side of the sewing fabric, and the thread hook part is moved to the edge of the fixed cutter, and the edge of the fixed cutter The portion is disposed close to the needle drop portion within a range that does not enter the vertical movement path of the needle, and the thread hook is cut by sliding contact between the thread catching portion and the edge portion of the fixed cutter to cut the thread hook. The end of the cut wire hook thread is elastically clamped between the movable cutter and the wire hook thread clamping member arranged at the lower part of the movable cutter, and is waiting for the next sewing.

In addition, the double loop stitch sewing machine of the second invention is a double loop stitch sewing machine including one or a plurality of needles that hold the needle thread and move up and down, and a thread hook that can hold the thread hook and move up and down with the needle. The forward and backward movement is performed in a direction slightly orthogonal to the path, and the needle coil formed by the above needle under the needle plate is captured during the in and out movement; the outer position on the side of the needle drop position in the needle plate and the needle drop can be captured. The other side of the position is driven back and forth, and the hooks held by the hooks are used to make the needle coils captured by the movement of the hooks in and out of each other in series. A double-loop stitching seam is formed on the moving sewing fabric conveyed on the needle plate. The double-loop stitching sewing machine has a thread cutting device that includes a movable cutter and a fixed cutter, and a thread hook thread holding member. The movable cutter and the fixed cutter After the double loop stitching is formed, the needle thread portion and the thread hook portion protruding on the back side of the sewing fabric are cut, and the end portion of the cut hook thread is elastically clamped to the thread. Between the hook thread holding member and the movable cutter, the double loop sewing machine is characterized by having: The needle thread holding mechanism can move closer to and away from the thread hook, and during the approach operation, the needle coil captured by the thread hook is held closer to the entry and exit ends of the thread hook than the lowered position of the needle. Position; the thread hook thread holding body can move close to and away from the thread hook, and keep the thread hook thread extending from the thread hook to the sewing fabric more forward than the lowering position of the needle during the approach motion Side position; a thread hook thread suppressing mechanism that suppresses the feeding of the thread hook toward the thread hook; and a control unit that controls the needle thread in association with the operation of the needle and the thread hook and the conveying and moving operation of the sewing fabric The holding mechanism and the hook and thread holding body are moved closer and farther. The control unit sets the thread hook to the in and out position, sets the needle to the raised position, and finishes normal sewing, and then performs at least one stitch including the following steps. With this, the needle coil is held by the needle and the needle coil is self-stringed into a loop to prevent the double loop suture from spreading. The above steps refer to Moving the needle thread holding mechanism closer to the needle coil at a position closer to the entry / exit side of the hook than the lowered position of the needle, and moving the hook thread holding body close to the hook to make the hook After the thread is positioned more forward than the lowered position of the needle, the thread hook thread suppressing mechanism is started to inhibit the thread hook thread from being sent to the thread hook, and the state is maintained until the needle is caught by the thread hook. After the needle coil is lowered, the position holding of the needle coil is released, and the needle is lowered by the needle coil in accordance with the lowering and rising of the needle, the forward and backward movement of the thread hook, and the conveying operation of the sewing fabric; The movable cutter in the thread cutting device is formed with a blade portion and a wired hook thread catching portion. After the fleece prevention action, when the movable cutter is at the position on the other side of the needle drop position and on the side During the reciprocating driving movement between the outer positions, the movable cutter moves from the position on one side of the needle drop position to the outside on the other side. When set to move the row driver, or the movable knife from said outer position on the other side on the side of the above-described When the position is driven back, the blade portion is cut or pulled to cut the needle thread portion protruding on the back side of the sewing fabric when the blade portion is near the needle drop position or the needle drop position. When the position on the other side is driven back to the outer position on the one side, the thread hook thread catching part hooks and catches the thread hook part protruding on the back side of the sewing fabric, and the fixed cutting in the thread cutting device The front ends of the knives and the thread-hook and thread-clamping members are arranged close to the needle drop portion within a range that does not enter the vertical movement path of the needle; when the movable cutter is on the other side from the needle drop position When the position is driven back to the external position on the side, the sliding contact between the thread hook and thread catching part and the fixed cutter cuts off the capture by the thread hook and thread catching part and is transferred to the fixed cutter. The thread hook portion up to the front end portion of the thread hook, and the end portion of the cut thread hook thread is elastically clamped between the movable cutter and the thread hook thread holding member, and is waiting for the next sewing.

According to the double-loop sewing method of the first invention and the double-loop sewing machine of the second invention having the above-mentioned features, after the normal sewing is completed by setting the thread hook in and out, the sewing process includes at least one stitch including the following steps. By this operation, the previous needle coil is self-connected by using the needle thread held by the lowered needle, and the self-serial loop is used to press the thread hook thread, which is prevented regardless of the amount of tension applied to the needle thread and the thread hook thread. The thread of the hook is pulled out, and the suture can be prevented from cracking even if other steps such as reinforcement stitching are not performed. The above steps refer to keeping the stitch coil captured by the hook closer to the thread than the lowering position of the needle. The position of the hook in and out end side is maintained until the needle is lowered by the needle coil captured by the thread hook, and then the position holding of the needle coil is released, and the needle is lowered by the needle coil.

In addition, after a predetermined sewing operation including the fleece prevention operation from the tandem ring (After the stitching is completed), with the fixed cutter positioned and fixed on the outer side closer to the needle drop position than on the other side, move the movable cutter from the outer side closer to the needle drop position. The position is driven to move to the above-mentioned external position on the other side, whereby the blade portion of the movable cutter can automatically cut the needle thread portion protruding on the back side of the sewing fabric at or near the needle drop position, so that The remaining length of the needlework section is shortened and can be cut to a certain length without deviation. On the other hand, when the movable cutter moves back from the outer position on the other side of the needle drop position to the outer position on the other side, the thread hook portion protruding on the back side of the sewing fabric is hooked by the thread hook thread catching portion. After hanging and catching, it can be automatically cut off by the sliding contact between the fixed cutter and the wire hook thread catching part, the remaining length of the wire hook wire is also as short as possible, and it can be cut to a certain length without deviation. The cutter is arranged in such a way that, at a position closer to the other side than the outer position on one side, the front end portion (the front edge of the blade portion) does not enter the upper and lower reciprocating motion path of the needle. Within the range, it is located closest to the needle drop position.

Therefore, when the stitching is completed, complicated manual operations such as the use of scissors are not required to cut the remaining length of the thread on the back side of the sewing fabric so as to shorten the remaining length of the thread. And other steps, which not only significantly improves the sewing operation efficiency (productivity) when continuously producing a large number of sewing products, but also does not damage the sewing fabric by scissors or the like, or does not cause the cutting position. The deviation of the thread cuts the remaining length of the thread too short and damages the anti-flapping effect caused by the self-stringing loop. The thread will not open after the self-anti-flapping suture seam, which can also improve the completion of the finished sewing product as a whole. And aesthetics.

In particular, in the first and second inventions, when the conveying movement of the sewing fabric has been stopped, or when the conveying movement is performed with a smaller conveying movement amount than that in the normal sewing, the execution of the The sewing action of at least one stitch that is stringed into a loop to prevent flaking can be made tight, and the self-serial loop part can be pressed against the hook hook thread, thereby preventing the hook hook thread from being stitched more effectively. The finished part was pulled out and spread due to its spread.

Further, in the first invention and the second invention, the blade portion of the movable cutter may be any one of the following three blade portions. The first blade portion is formed as follows: When the movable cutter is When the position of one side of the needle drop position is moved to the outer position of the other side, the needle thread part protruding on the back side of the sewing fabric is cut and cut; the second type of blade part is formed as follows: When the movable cutter When the outer position on the other side of the needle drop position is moved back to the position on the other side, the needle thread is cut off by pulling; or the third type of blade is formed as follows: When the movable cutter When the position on one side is moved toward the outer position on the other side, the needle thread portion is wiped off from the side. Among them, the following blade portion is particularly preferred. The blade portion is formed in the following manner: When the position on one side is moved toward the outer position on the other side, the needle thread portion is cut and cut.

In this case, there is no need to adopt a special shape in order to allow the cutting edge portion of the movable cutter to smoothly pass through the needle coil. Compared with the case of pulling or cutting on the side, the cutting edge portion is simple to manufacture and can be reliably made. Cut off the needlework section neatly.

Further, in the first invention and the second invention, it is preferable that after the hook thread is positioned more forward than the lowered position of the needle, the feeding of the hook thread toward the hook is suppressed.

In this case, it is possible to apply a predetermined tension to the thread hook thread extending from the front end of the thread hook to the sewing fabric, to strengthen the tension of the thread hook thread, and to prevent the thread hook thread from being pulled out. The short length also improves the aesthetic appearance of the suture, which can improve the quality of the suture.

In the double loop sewing machine according to the second invention, it is preferable to further include The thread hook thread holding body can move close to and away from the thread hook separately from the needle thread holding mechanism, and keep the thread hook thread extending from the thread hook to the sewing fabric at a position closer to that of the needle during the approach operation. The lowered position is closer to the front or rear side.

In this case, as with the needle thread holding mechanism, after the thread hook is put in and out to end the normal sewing, the thread hook is held by the thread hook thread holding body, and the thread hook is extended to the position of the sewing fabric. The thread of the hook is held more forward or rearward than the lowered position of the needle, whereby not only the needle thread can be reliably positioned, but also the hook thread can be reliably positioned. Therefore, the self-tandem loop can be implemented more reliably, and the effect of preventing the suture seam from spreading can be more reliably achieved.

In addition, the double-loop stitching sewing machine of the second invention is suitable for a case where a horizontal-cylindrical double-loop stitching sewing machine is targeted, but a single-needle double-loop stitching sewing machine or a flat-type double-loop stitching sewing machine other than the horizontal cylinder may be used as the target sewing machine.

1‧‧‧ wire hook

2a, 2b‧‧‧needle

3‧‧‧ hanging hook

4‧‧‧ stop member

6‧‧‧ thread hook thread retaining body

8‧‧‧Control Department

10‧‧‧ line hook line

12‧‧‧ Needle plate

20a, 20b ‧‧‧ Needlework

20a1, 20b1 ‧‧‧ Needlework Department

20a2, 20b2 ‧‧‧ Needle Coils

50‧‧‧ movable cutter

50a‧‧‧Line hook line capture section

50e‧‧‧Blade

51‧‧‧ fixed cutter

51e‧‧‧Edge

52‧‧‧Wire hook wire clamp

55‧‧‧ Needlework Pressing Device

83‧‧‧Transport reduction agency

84‧‧‧Line hook and wire suppression mechanism

A‧‧‧ Needle drop position

B‧‧‧ Sewing Machine

M‧‧‧Double loop suture

H‧‧‧Flameproof device

W‧‧‧ Sewing Fabric

Fig. 1 is a perspective view showing the overall appearance of a horizontal cylindrical double-loop sewing machine according to a first embodiment of the present invention.

Fig. 2 is a perspective view showing the structure of a main part of a seam preventing flare device in the horizontal cylindrical double-loop sewing machine.

FIG. 3 is a perspective view showing a state where a part of a configuration of a main part of the suture-scraping prevention device is removed.

Fig. 4 is a plan view showing the structure of a main part of the suture-scraping prevention device.

Fig. 5 illustrates the structure and the first operation of the stopper mechanism of the suture-prevention device; Bottom view of the main part of Ming.

FIG. 6 is a bottom view of a main part explaining the configuration and the second operation of the stopper mechanism.

FIG. 7 is a bottom view of a main part explaining the configuration and the third operation of the stopper mechanism.

FIG. 8 is a bottom view of a main part explaining the configuration and fourth operation of the stopper mechanism.

FIG. 9 is an exploded perspective view illustrating the configuration of a reciprocating driving movement mechanism of a thread cutting device in a horizontal cylindrical double-loop sewing machine.

FIG. 10 shows a state where the thread trimming device is retracted to the retracted position by the reciprocating driving moving mechanism. (A) is a plan view of a main part, and (B) is a longitudinal sectional view taken along line A-A in FIG. 10 (A).

FIG. 11 shows a state where the thread cutting device is moved in and out by the reciprocating driving moving mechanism. (A) is a plan view of a main part, and (B) is a longitudinal sectional view taken along line A-A in FIG.

FIG. 12 is a diagram for explaining the detailed positional relationship between the forward and backward reciprocating motion paths of the fixed cutter and the thread holding member in the thread cutting device and the right needle in the case of the first embodiment of the present invention and the case of the prior art; The main part comparison chart, (A) is the case of the first embodiment of the present invention, and (B) is the case of the prior art.

Fig. 13 is an enlarged plan view of a movable cutter in the thread cutting device according to the first embodiment.

Fig. 14 is a block diagram showing the configuration of a control system of a horizontal cylindrical double-loop sewing machine including a suture-scraping prevention device according to the first embodiment.

FIG. 15 is a timing chart showing the content of operations of the control unit for preventing the suture seam from spreading over time.

FIG. 16 is an explanatory view of a first flaking prevention operation of the suture prevention flaking device. FIG.

FIG. 17 is an explanatory diagram of a second fleece prevention operation of the suture prevention fleece prevention device. FIG.

Fig. 18 is an explanatory view of a third fleece prevention operation of the suture prevention fleece device.

Fig. 19 is an explanatory view of a fourth fleece prevention operation of the suture fleece prevention device;

Fig. 20 is an explanatory view of a fifth fretting preventing operation of the suture fleeing preventing device;

21 (a) to (f) are perspective views of main parts for sequentially explaining a tangent operation of the tangent device.

Fig. 22 is a view of the structure of a double-loop stitching seam formed by the horizontal cylindrical double-loop stitching sewing machine of the first embodiment, as viewed from the back of the sewing fabric.

Fig. 23 is an enlarged plan view of a movable cutter of a thread cutting device in a horizontal cylindrical double-loop sewing machine according to a second embodiment of the present invention.

Fig. 24 is a bottom view schematically showing the structure of a stitched seam of a stitched completed portion of a general double loop stitching.

Fig. 25 is a plan view schematically showing a configuration of a main part of a suture-prevention device according to the prior art invented by the present applicant.

FIG. 26 is a plan view for explaining an operation state of a main part of the suture-scraping prevention device in the prior art described by the present applicant.

Fig. 27 is a view of the structure of a double loop stitched seam obtained from the back of the stitched fabric in the prior art invented by the applicant, as viewed from the back of the sewn fabric.

FIG. 28 shows a state where the thread cutting device in the prior art invented by the present applicant enters and exits at an entry / exit position by reciprocatingly driving the moving mechanism. (A) is a plan view of the main part, and (B) is a view along FIG. Vertical section view of CC line.

Figs. 29 (a) to (f) are perspective views of main parts sequentially explaining the tangent operation of the tangent device in the prior art invented by the present applicant.

Hereinafter, embodiments of the present invention will be described based on the drawings.

Fig. 1 is a perspective view of the overall appearance of a horizontal cylindrical double-loop sewing machine according to the first embodiment of the present invention, and Figs. 2 and 3 are diagrams showing the main parts of the seam-prevention device provided with the horizontal cylindrical double-loop sewing machine of the first embodiment; FIG. 4 is a plan view showing the structure of the main part of the above-mentioned suture-prevention device, and FIG. 5 to FIG. 8 are the main descriptions of the structure of the stopper mechanism and the first to fourth operations of the anti-extrusion device. Partial bottom view.

9 is an exploded perspective view illustrating the configuration of the reciprocating driving moving mechanism in the thread cutting device of the horizontal cylindrical double-loop sewing machine, and FIG. 10 shows a state where the thread cutting device is retracted to the retracted position by the reciprocating driving moving mechanism. (A) is a plan view of the main part, (B) is a vertical cross-sectional view taken along the line AA of FIG. 10 (A), and FIG. 11 shows that the cutting device is moved in and out by the reciprocating driving movement mechanism described above, and can be moved and cut (A) is a plan view of the main part, and (B) is a longitudinal sectional view taken along the line BB of FIG. 11 (A).

In addition, in the following description, the description of "left and right" and "front and back" shown by arrows in Figs. 2 to 4 and 9 to 11 will be described. Here, "front" refers to one side of the sewing operator, "rear" refers to one side of the sewing operator, and "left and right" refers to "left and right" when viewed from the front side of the sewing operator.

As shown in FIG. 1, in the horizontal-cylindrical double-loop sewing machine of the first embodiment, the sewing machine arm portion C and the sewing machine bed portion B extend to the left from the upper and lower positions of the sewing machine main body portion D, and extend slightly parallel to each other. Inside the sewing machine arm C, a driving shaft for driving, a needle driving mechanism for moving the left and right needles 2a, 2b up and down, a cloth pressing foot driving mechanism for moving the presser foot 25 up and down, or the above driving mechanisms are incorporated. Power transmission mechanism, etc., but due to the Such driving mechanisms or power transmission mechanisms are well known, so descriptions are omitted.

As shown in FIG. 4, the horizontal cylindrical double-loop sewing sewing machine includes a thread hook 1, left and right needles 2a, 2b (see FIGS. 16 to 21), a needle plate table 11 mounted on the upper surface of the sewing machine bed portion B, The needle board table 11 is provided with a suture-prevention device H and a needle board 12 mounted on the needle board table 11.

In the sewing machine shuttle bed portion B of the lower portion of the needle plate 12, a wire hook 1, a thread cutting device 5, a reciprocating drive moving mechanism 70, and the like are installed. The wire hook 1 holds the thread hook 10 and extends along the same distances as the needles 2a, The upward and downward reciprocating motion path of 2b performs the forward and backward movements in the left-right direction which is slightly orthogonal. The reciprocating driving moving mechanism 70 causes the edge portion 51e of the fixed cutter 51 of the thread cutting device 5 to be as shown in FIGS. 10 (A) and (B). The forward and backward position P1 toward the left and forward, and the retreat position P2, which is further to the right and rear than the above entry and exit position P1 as shown in Figs. 11 (A) and (B), are driven back and forth, and the thread cutting device 5 has been moved to In the state of the above-mentioned entry and exit position P1, only the movable cutter 50 described below is positioned in a straight line along the xy direction between the outer position on one side (right side) and the outer position on the other side (left side) of the needle drop position. The ground is moved back and forth, and the above-mentioned leftward and forward position P1 is a position close to the needle plate 12 and the thread hook 1, and is a position when an abutment member 34 described later abuts on a stopper member 33 described later.

The left and right needles 2a and 2b are attached to a lower end portion of a needle bar (not shown), and the needle bar is raised and lowered in association with the rotation of a transmission rotation shaft (not shown) in the arm portion C of the sewing machine. A and A in FIGS. 2 and 4 indicate the needle drop positions (lowering positions) of the needles 2 a and 2 b. The needle drop positions A and A are set at intervals in the left-right direction and are set at approximately the center of the needle plate 12.

The thread hook 1 is disposed in the sewing machine shuttle bed portion B, and the movement of the hook driving mechanism (not shown) is slightly orthogonal to the vertical movement paths of the needles 2a and 2b to the needles 2a and 2b. 2b moves forward and backward (leftward and rightward) in the side-by-side direction. The solid line in FIG. 4 indicates a state in which the hook 1 is operating in a leftward position, and the dotted line in FIG. 4 indicates a state in which the hook 1 is operating in a rightward retracted position. As shown by the solid line in FIG. 4, the front end portion of the thread hook 1 in the left advance position extends beyond the needle drop positions A and A to the left. As shown by the dotted line in FIG. The distal end portion is located away from the needle drop positions A and A to the right.

The horizontal-cylindrical double-loop stitching sewing machine sew the sewing fabric (not shown) placed on the needle plate 12 by raising and lowering the needles 2a and 2b and moving left and right of the thread hook 1. The sewing fabric is pressed against the throat plate 12 by the presser foot 25, and is moved in the direction of the arrow Y in FIG. 4 by the operation of a transport mechanism provided inside the sewing machine shuttle bed B. The conveying mechanism has conveying teeth that repeatedly perform the following operations. The action is directed toward the needle plate 12 and then moves backward. After immersing in the needle plate 12, it moves back forward. The sewing fabric is conveyed by this conveying. The teeth intermittently move in the direction of arrow Y.

The needle bar, the hook driving mechanism, and the conveying mechanism are well-known mechanisms that operate in synchronization with each other by a transmission action of a transmission rotation shaft (not shown). The needles 2a and 2b hold the needle threads 20a and 20b (refer to FIGS. 16 to 21), and while the sewing fabric stops conveying and moving, penetrate through the sewing fabric to reach below the needle plate 12, and then rise and pull out above the sewing fabric. The thread hook 1 holds the thread hook 10 (refer to FIGS. 16 to 21), advances to the left as the needles 2 a and 2 b start to rise, and captures the needle coils 20 a 2 and 20 b 2 of the needle threads 20 a and 20 b formed under the needle plate 12. The sewing fabric is conveyed and moved when the needles 2a and 2b are raised. The needles 2a and 2b descend through the sewing fabric that is being conveyed and move, and catch the thread hook thread 10 held by the thread hook 1 that is retracting to the right. The double loop sewing machine repeats the above operations to form a double loop sewing seam on the sewing fabric.

Secondly, first, the seams of the horizontal cylindrical double-loop sewing machine The seam preventing flare device H will be described in detail. The anti-flapping device H includes a needle thread holding mechanism, a stop mechanism, and a hook 35 as a connecting member that connects the hook 3 (described later) of the needle thread holding mechanism and the stop member 4 (described later) of the stop mechanism in a linked manner. And control unit 8 (to be described later).

The above-mentioned needle thread holding mechanism has a hanging hook 3 and a reciprocating thread-operating cylinder 32 which makes the hanging hook 3 in a standby position away from the thread hook 1 and a thread hanging near the thread hook 1 Between the positions, the support shaft 30 in the up-down direction is used as a center to drive and swing. A support shaft 30 serving as a swing center of the hanging hook 3 is disposed near the right rear corner of the throat plate 12 and is supported on the throat plate base 11.

The hanging hook 3 has an arc-shaped curved shape, and is connected to a front end portion of a support arm 3e extending to the left from the support shaft 30 so as to be folded back. The front end portion of the thread hook 3 is located below the needle plate 12 and faces the needle drop positions A and A from the left rear side. A hook portion 3b protruding outward is formed at the front end portion. The support arm 3e includes an extension portion 3c extending forward from the support shaft 30, and one end portion of the connecting rod 35 is connected to a front end portion of the extension portion 3c.

As shown in FIG. 4, the wire hook and wire holding body 6 having an arc-shaped curved shape is fastened to the base of the wire hook 3 through two fixing screws 60 and 60. The front end portion of the thread hook thread holding body 6 extends substantially forward along the left side of the thread hook 3, and faces the needle drop positions A and A at a forward position of the front end portion of the thread hook 3. A split hook receiving portion 6 a is formed at the front end portion of the hook and thread holding body 6. By loosening the fixing screws 60 and 60, the position of the thread hook thread holding body 6 with respect to the hook 3 can be adjusted, and by adjusting the position, the thread hook thread receiving portion 6a at the front end securely holds the thread hook thread 10.

As shown in FIGS. 5 to 8, the stopper mechanism includes a stopper member 14 which is fixed to a front end portion (left end portion) of the output lever 31 of the wire-operated cylinder 32 through a stop screw 36, The wire-operated cylinder 32 performs a telescoping operation using the operating air supplied through the air pipe 33, whereby the stopper member 14 linearly drives back and forth in the left-right direction; the rocker lever 9 can be engaged with the stopper A part of the member 14 and release of engagement; a spring 96 that engages the rocking lever 9 to a part of the stopper member 14 and swings and applies pressure in a direction in which the hanging hook 3 is in a standby position; and a single action (toward The left-side ejection-type) blocking cylinder 42 forcibly releases the rocking lever 9 from a part of the blocking member 14 against the biasing pressure of the spring 96.

The stopper cylinder 42 is ejected in the left direction by using the operating air supplied through the air pipe 43, and the output lever 41 of the stopper cylinder 42 causes the rocker lever 9 to counterclockwise against the pressure of the spring 96. Shake the direction.

The swing lever 9 is supported on the upper surface of the swing lever mounting base 92 so as to be swingable around a support shaft 90 that can be moved in the vertical direction. The rocker lever 9 has an engaging hook 9a at a front end thereof that can be engaged with a part of the stopper member 14. As shown in FIG. 5, when the stopper member 14 is extended by the line operation of the cylinder 32 (see FIG. 3), When driving to the left, that is, when the hook 3 is moved to the standby position, the rocking lever 9 is in contact with the side of the stopper member 14 by the pressure of the spring 96. When the stopper member 14 is operated by the thread When the cylinder 32 is contracted to move in the right direction, as shown in FIG. 6, the rocking lever 9 swings clockwise around the support shaft 90 by the pressure of the spring 96, and the engaging hook 9a at the front end It is in a state capable of being engaged with a part of the stopper member 14.

Further, as shown in FIG. 7, the contracted wire operating cylinder 32 (see FIG. 3) is extended slightly again to thereby engage the engaging hook 9 a at the tip of the rocker lever 9 with a part of the stopper member 14. The stopper member 14 temporarily stops the driving movement in the left direction. To stop In the state where the member 14 is temporarily stopped, the hanging hook 3 is moved to a holding position between the standby position and the hanging position through the connecting rod 35. At this time, the hook portion 3b at the front end of the thread hook 3 moves leftward and rearward from the thread hook position (needle drop positions A and A) shown in FIG. 4, and hooks the thread 20a and 20b to be held at the holding position.

Further, as shown in FIG. 8, the output lever 41 is pushed out and driven in the left direction as the stopper cylinder 42 is extended, whereby the rocker lever 9 swings counterclockwise against the pressure of the spring 96, and the rocking The engaging hook 9 a at the front end of the lever 9 is released from engagement with a part of the stopper member 14, and the temporary stop of the stopper member 14 is released. Thereby, the thread operating cylinder 32 performs the extension operation to the maximum extent, and the thread hanging hook 3 swings back to the standby position through the connecting rod 35.

As described above, in the first embodiment, the thread hanging hook 3 of the needle thread holding mechanism is moved between the standby position, the thread hanging position, and the holding position by the telescopic operation of the thread operating cylinder 32 and the blocking cylinder 42.

In the horizontal cylindrical double-loop sewing machine of the first embodiment, the needle plate table 11 mounted on the upper surface of the shuttle bed section B of the sewing machine is shown in Figs. With the right needle plate base 11R. The needle plate 12 is detachably mounted on the upper surface of the left needle plate base portion 11L through a set screw 100, and supports a support shaft 30 serving as a swing center of the hanging hook 3 of the needle thread holding mechanism.

There are a plurality of positions (2 positions) in front of and behind the left end part near the left end portion of the left needle plate base portion 11L divided into two, specifically, the front end (left end) of the sewing machine arm portion C shown by the imaginary line in FIG. 4. In the vicinity, a screw hole 101 is formed at a portion separated from the mounting portion of the above-mentioned needle plate 12, and the left needle plate base portion 11L can be fastened and released through a stop screw member 102 screwed into these screw holes 101 ( It can be attached and detached to the upper surface of the shuttle bed part B of the sewing machine.

Further, on the upper surface of the sewing machine shuttle bed portion B and the left needle plate base portion 11L, as shown in FIG. 3, ejection pins 103 are formed at two positions away from the fastening portions of the stop screw member 102. And the pin hole 104 into which the ejection pin 103 is fitted, and the pin hole 104 is inserted into the ejection pin 103 from above to thereby engage the left needle plate table with a predetermined position and posture relative to the sewing machine shuttle bed portion B. The portion 11L is positioned, and the stopper screw member 102 is screwed into the screw hole 101 in this state, whereby the left needle plate base portion 11L can be fastened to the upper surface of the sewing machine shuttle bed portion B.

Furthermore, in the first embodiment, it has been described and illustrated that the ejection pin 103 projects upward from the upper surface of the sewing machine bed portion B, and the pin hole 104 is formed in the left needle plate base portion 11L, but the ejection pin 103 It is also possible to protrude downward from the lower surface of the left needle plate base portion 11L, and a pin hole 104 is formed on the upper surface of the sewing machine shuttle bed portion B.

On the other hand, the divided right needle plate base portion 11R constitutes a cylinder mounting base portion (hereinafter, the right needle plate base portion 11R is referred to as a cylinder mounting base portion), and the cylinder mounting base portion supports the above-mentioned line-operated cylinder 32 And a stopper cylinder 42, and the stopper mechanism is arranged below the cylinder mounting base portion 11R. In detail, as shown in FIG. 5 to FIG. 8, the line-operated cylinder 32 is fixedly supported on the lower surface of the cylinder mounting base portion 11R through the mounting screw 105, and the stopper cylinder 42 is arranged on the line in a state of two-stage overlapping. The lower portion of the air cylinder 32 is operated, and the stopper cylinder 42 is fixedly supported by the air cylinder mounting base portion 11R through a mounting screw 106.

The cylinder mounting base portion 11R is fixed to the rear surface of the sewing machine shuttle bed portion B through the set screw member 107. Here, the fixed state refers to a state in which, when the flaking preventing device H is assembled to the sewing machine bed portion B, it is fixed in a predetermined position by tightening the stop screw member 107, and is not performed after assembly. Position adjustment, etc. Assembly position.

One end (right end) of the connecting rod 35 is rotatably connected to the stopper member 14 in the stopper mechanism by a pin screw 108. The cylinder mounting base portion 11R at a position corresponding to the following connection portion is formed with a long groove 109 that is longer in the left-right direction to allow linear movement in the left-right direction in accordance with the expansion and contraction of the line-operated cylinder 32. The linearly reciprocating movement of the stopper member 14 is described above. The above-mentioned connection portion is a connection portion formed by connecting one end of the connecting rod 35 and the stopper member 14 with a pin screw 108.

Further, the connection end portion 35a is bent downward substantially by the thickness of the extension portion 3c, and the connection end portion 35a is connected to the extension portion 3c connected to the hanging hook 3 at the other end of the connection rod 35. At the connecting end portion 35 a of the connecting rod 35 that is bent downward, a plug pin 110 projects upward. On the other hand, a connecting hole 111 is formed in the extension portion 3 c, and the connecting hole 111 can pass from above the plug pin 110. It is inserted into the latch 110 and can be pulled out upward.

Thereby, when the left needle plate base portion 11L is released from the sewing machine shuttle bed portion B and removed from the sewing machine shuttle bed portion B, the following operation is not required. This operation refers to the connection of the connecting rod 35 and the extension. The setting portion 3c can be fixedly connected, for example, by a loosening operation such as a set screw to release the linkage state between the two. As long as the left needle plate base portion 11L is lifted upward, the extension portion 3c can be pulled upward from the latch 110. The connection hole 111 releases the linkage state between the connection lever 35 and the extension portion 3c (the hook 3). In addition, when the left needle plate base portion 11L is mounted on the sewing machine shuttle bed portion B, the connection hole 111 can be inserted into the latch 110 from above as long as the left needle plate base portion 11L is moved from the upper direction to the sewing machine shuttle bed portion B. Thus, the connecting rod 35 and the extension portion 3c (the hook 3) are returned to the linked state. The connection end portion 35a of the connection rod 35 does not necessarily have to be bent downward. That is, the connecting rod 35 may be a flat plate-shaped connecting rod that is flat over its entire length.

Furthermore, the rocker mounting base 92 is mounted on the cylinder mounting base portion 11R through a long slot 93 and a set screw 94 in the left-right direction so as to be able to adjust the position left and right. The support shaft 90 is swingably supported by the swing lever 9 in the stop mechanism as a center. Even after the cylinder mounting base portion 11R is fixedly assembled to the sewing machine shuttle bed portion B through the stop screw member 107, the position of the rocker mounting base 92 can be adjusted arbitrarily with respect to the cylinder mounting base portion 11R. The timing of pulling out the hook 1 from the needle coils 20a2 and 20b2 held by the hanging hook 3 can be adjusted, thereby making it possible to reliably perform the self-tandem loop for preventing the sewing seam from spreading.

As described above, the horizontal cylindrical double-loop stitching sewing machine of the first embodiment adopts a structure in which the needle plate base 11 is divided into two parts: a left needle plate base part 11L and a right needle plate base part 11R. When the seam preventing device H is assembled on the sewing machine shuttle bed section B, the left and right needle plate table sections 11L and the right cylinder mounting table section 11R of the needle plate table 11 which is divided into left and right can be respectively installed on the sewing machine shuttle bed section B. . Therefore, compared with the case where the left and right needle plate table sections 11L and 11R are integrated, and one needle plate table which is longer and larger in the left and right direction can be processed, it can be easily performed with less labor. Mounting (assembling) the entire anti-flap device H on the shuttle bed portion B of the sewing machine.

After the needle plate table 11 (the left needle plate table section 11L and the right cylinder mounting table section 11R) is temporarily assembled in the sewing machine shuttle bed section B, for example, when the thread hook 1 or its operating member needs to be corrected on the needle plate The position or movement trajectory of the sewing member inside the sewing machine shuttle bed section B at the lower part of the table 11 is used to adjust the sewing tension, or when various parts required to be stored inside the sewing machine shuttle bed section B at the lower part of the needle plate table 11 are repaired or For maintenance such as replacement, it is not necessary to remove the cylinder mounting base portion 11R from the sewing machine shuttle bed portion B, and the air cylinder 33 is assembled and connected to the cylinder mounting base portion 11R. When operating the cylinder 32 and the stop cylinder 43 with the line 43 and 43, it is firmly fixed and supported at a predetermined position. As long as it is released from the sewing machine shuttle bed section B and only the left needle plate table section 11L is removed, it can be ensured to be sufficiently large The working space allows easy adjustment or maintenance of the suture tension.

Next, the thread trimming mechanism 5 provided in the horizontal-cylindrical double-loop sewing machine of the first embodiment will be described. As shown in FIG. 9 to FIG. 11, the thread cutting mechanism 5 is configured as follows: The thread cutting device 5 can drive the moving mechanism 70 by reciprocating motion, and at the above-mentioned entry-exit position P1 near the needle plate 12 and the thread hook 1, and The entry / exit position P1 is moved back and forth between the retreat position P2 on the right rear. Further, the thread cutting device 5 includes a movable cutter 50 for thread cutting, which cuts off the left and right needle thread portions 20a1, 20b1, which protrude from the back side of the sewing fabric W after a predetermined sewing operation is completed, that is, when the sewing is completed. Wire hook and thread portion 10a; the fixed cutter 51, whose blade portion 51e is at the above-mentioned entry / exit position P1, is disposed within a range of the vertical reciprocating motion path of the right needle 2b among the left and right needles 2a and 2b, The position closest to the needle drop position; a flat spring thread hook thread holding member 52 is disposed below the movable cutter 50 and elastically clamps the cut thread between the movable cutter 50 and the movable cutter 50 An end portion of the hook wire 10; and a wire holding assist spring 53 for adjusting a holding force of the wire hook wire holding member 52.

Here, referring to the comparison diagrams of FIGS. 12 (A) and (B), the positions of the fixed cutter 51 and the hook and wire clamping member 52 at the above-mentioned entry / exit position P1 in the case of the first embodiment will be specifically described. The relationship with the positions of the fixed cutter 51 and the wire hook wire holding member 52 at the above-mentioned entry / exit position P1 in the case of the prior art invented by the present applicant.

Fig. 12 (A) shows the positions of the fixed cutter 51 and the wire hook and wire holding member 52 in the case of the first embodiment, and Fig. 12 (B) shows the positions of these members in the case of the prior art. In the case of the first embodiment, as shown in FIG. 12 (A), the edge portion 51e of the fixed cutter 51 is set The distance d between the front end of the front end and the front end portion 52e of the wire hook thread holding member 52 and the up and down movement path of the right needle 2b is as close to zero as possible, and is smaller than the distance d1 in the case of the prior art (d < d1), that is, a position that is located closest to the up-and-down motion path of the right needle 2b, compared with the case of the prior art shown in FIG. 12 (B), the fixed cutter 51 is extended to the left and extended. And wire hook wire holding member 52.

As shown in FIG. 13, the movable cutter 50 is formed of a strip-shaped plate material which is longer in the left-right direction, and has a blade portion 50 e near the front end of the movable cutter 50 composed of the longer strip material. When the movable cutter 50 is driven and moved from the external position on the one side (right side) to the external position on the other side (left side) of the movable cutter 50 from the above-mentioned entry / exit position P1, that is, the needle drop position, the needle cutting position A, A or near the needle drop positions A and A, the left and right needle thread portions 20b1 and 20a1 protruding from the left and right sides of the sewing fabric W on the needle plate 12 are sequentially cut and cut, and the blade portion 50e is such that the leading edge is located on the belt. It is formed so that it may become the lower surface side of the plate | board thickness direction of a sheet material.

A wire hook catching portion 50a is formed at a front end portion of the movable cutter 50 made of the longer strip-shaped plate, and the wire hook catching portion 50a is positioned close to the movable cutter 50 from the needle drop position. When the external position on one side (left side) is driven back to the external position on the other side (right side), the thread hooking portion 10a protruding from the back side of the sewing fabric W caught on the needle plate 12 is hooked to make the thread The thread hooking portion 10a captured by the hook thread catching portion 50a is moved to a position closer to the other side (right side) than the outer position on one side (right side) of the needle drop position, and the thread hooking unit 50a is in sliding contact with the edge portion 51e of the fixed blade 51 to cut the wire hook portion 10a.

The reciprocating driving moving mechanism 70 is configured as shown in FIGS. 9, 10 (A), (B), and 11 (A), (B). The reciprocating driving moving mechanism 70 keeps the thread trimming device 5 in the in-out position. Driven back and forth between P1 and the above-mentioned retreat position P2, and the thread trimmer 5 has moved In the state of entering and exiting the position P1, only the movable cutter 50 is positioned in a straight line along the xy direction between the outer position on one side (right side) of the needle drop position and the outer position on the other side (left side). Ground back and forth to drive movement.

That is, the lower surface of the right end portion of the movable cutter 50 is fixed to the movable cutter table 124 through the screw 123. A U-shaped notch portion 125 is formed at a substantially central portion in the longitudinal direction (left-right direction) of the movable cutter table 124, and the left and right positions sandwiching the notch portion 125 are along the longitudinal direction of the movable cutter table 124. A pair of long left and right slits 126a and 126b are formed.

The fixed cutter 51 is disposed on the upper surface of the movable cutter 50, and the cutter table guide 127 and the right end portions of the hook and wire clamping member 52 are overlapped and disposed on the lower surface of the right end portion of the fixed cutter 51. The fixed cutter 51, the cutter table guide 127, and the hook and wire clamping member 52 are fixed to the left end portion of the fixed cutter table 129 through a screw 128. The movable cutter table 124 is inserted into the pair of left and right links through small bolts 148 inserted into the back (lower surface) of the fixed cutter table 129 and the upper surface sides of the left and right pair of links 140a and 140b. The flanged cylindrical nuts 131a and 131b at one end of 140a and 140b are in a state where the flanged cylindrical nuts 131a and 131b allow one end of the left and right pair of links 140a and 140b to rotate. And it is clamped in the state which can slide and move within the length range of the left and right pair of slits 126a and 126b of the said movable cutter table 124.

The other ends of the pair of left and right links 140a and 140b are screwed to the device mounting base 130 through flanged sleeves 141a, 141b and flat head screws 142a, 142b. The flanged sleeves 141a, 141b are from the above. The upper surface sides of the pair of left and right links 140a and 140b are inserted and allowed to rotate in the other ends of the pair of left and right links 140a and 140b. Thereby, the movable cutter table 124 and the fixed cutter table 129 can move to the left with the swinging motion of the left and right pair of links 140a and 140b. The state of back and forth movement in the right direction is supported by the device mounting base 130.

Furthermore, of the flanged sleeves 141a and 141b, the flanged sleeve 141b on the right side is formed into an eccentric cam shape, so that the distance between the two ends of the holes on the right side link 140b can be changed to the left side. The flanged sleeve 141a of the connecting rod 140a is a fulcrum, and the needle drop position of the movable cutter 50 at the above-mentioned entry and exit position P1 of the thread trimming device 5 and the position of the starting point of the movement in and out of the cloth conveying direction with respect to the thread hook 1 Make fine adjustments.

An abutment member 134 is formed on the fixed cutter table 129, and the abutment member 134 abuts on a position below the left link 140a of the left and right pair of links 140a and 140b, and is screwed to the device installation. But not limited to 130.

Further, an engaging protrusion 136 is formed at a rear portion of the central portion of the fixed cutter base 129 in the longitudinal direction, and the engaging protrusion 136 and a protrusion 135 protruding rearward from a position slightly to the right of the left end of the movable cutter base 124 are formed. Butt separation. The movable cutter table 124 cannot move further to the right alone because the engaging projection 136 abuts on the projection 135. In addition, the movable cutter table 124 is elastically urged so as to always move in the left direction through a spring 137, which is screwed to the device mounting table 130 and has one end portion and the right end of the contact member 134. Face elastic contact.

A slot 146 is formed in the device mounting table 130, and the fixed cutter table 129 is inserted into the slot 146 in a freely sliding manner in the left-right direction. The slot 146 is fixed to the sewing machine shuttle through a plurality of screws 147 arranged around the slot. Bed section B. A drive rod 145 is mounted on the device mounting base 130, and the driving rod 145 is pivotally connected to the front end portion of the piston 148 of the tangent cylinder 48 through a shoulder screw 143. 144 is a center and is driven in the direction of arrow ab. The tapered round portion 145a of the front end of the driving rod 145 engages In the U-shaped notch portion 125, the U-shaped notch portion 125 is formed at a substantially central portion of the movable cutter table 124.

According to the reciprocating drive moving mechanism 70 configured as described above, as shown in FIGS. 10 (A) and (B), when the driving rod 145 is driven to swing in the direction b as the piston 148 of the thread trimming cylinder 48 is extended, the thread trimming device 5 resists. The elastic force of the spring 137 moves to the right, the engaging protrusion 136 and the protrusion 135 are in abutting state, and the cylindrical nuts 131a and 131b of the left and right pair of links 140a and 140b move to the left and right pair of slits 126a, In the leftmost state in 126b, the left end face of the abutment member 134 of the fixed cutter table 129 is separated from the stopper member 133. In this state, the thread trimming device 5 is in the retracted position P2 and stands by in an inclined posture that does not hinder the movement of the thread hook 1.

Next, as shown in FIGS. 11 (A) and (B), if the drive rod 145 is driven to swing in the direction a due to the contraction of the piston 148, the abutment member 134 of the fixed cutter table 129 is pressed by the elasticity of the spring 137. And move to the left. Accordingly, in a state where the engaging protrusion 136 and the protrusion 135 abut, the thread trimming device 5 reduces the inclination angle of the above-mentioned inclined posture due to the swing of the left and right pair of links 140a and 140b, and fixes the abutment of the cutter table 129. The left end of the contact member 134 moves to the left until it comes into contact with the stopper member 133. As a result, the thread trimming device 5 is moved to the entering / exiting position P1, and is in a posture slightly orthogonal to the direction in which the suture proceeds.

When the piston 148 is further contracted from this state, and the driving lever 145 is driven to swing in the direction a, the movable cutter table 124 passes the needle drop position of the needle plate 12 while the fixed cutter table 129 stays at the above-mentioned in-out position P1. Move left (x direction). That is, only the movable cutter 50 fixed to the movable cutter table 124 advances leftward (moves forward) between the needle plate 12 and the thread hook 1. At this time, the movable cutter table 124 and the fixed cutter table 129 are supported in the state of being able to move back and forth in the left-right direction in accordance with the rocking motion of the left and right pair of links 140a and 140b. The stage 130 is thus controlled so that the movable cutter 50 moves linearly by a pair of left and right links 140a and 140b.

Next, the drive rod 145 is driven to swing in the direction b as the piston 148 is extended. Accordingly, the leftmost position of the movable cutter 50 which moves forward by itself moves to the right direction (y direction), and moves back to the right (return movement) to the lower part of the fixed cutter 51 which is in standby at the aforementioned entry / exit position P1. The piston 148 further shrinks from this state, whereby the thread trimming device 5 moves backward to the retreat position P2 shown in Figs. 10 (A) and (B).

In addition to the structure and device described above, the double loop sewing machine of the first embodiment also includes a needle thread pressing device 55 and a thread release device.

As shown in FIG. 1, the needle thread pressing device 55 is attached to the sewing machine arm portion C above the needle plate 12 through the bracket 56. Although the illustration is omitted, the needle thread pressing device 55 is configured by abutting and separating a pair of front and rear needle thread pressing plates through a cylinder and a spring. When the sewing is completed, when the movable cutter 50 of the thread cutting device 5 is 铡When the needle thread portions 20 a 1 and 20 b 1 are cut, the needle threads 20 a and 20 b are pressed and held by the pair of needle thread pressing plates on the upper portion of the needle plate 12. Thereby, the needle thread pressing device 55 has a function of making the blade portion 50e of the movable cutter 50 surely cut and cut the needle thread portions 20a1 and 20b1.

In addition, the thread release device lifts the thread tension discs 57 and 58 (refer to FIG. 1) (relaxes the threads) while the movable cutter 50 starts to move in a row, so that the needle threads 20 a and 20 b and the thread hook are instantaneously fed out. 10. The thread unclamping device 10 is used to loosen the thread hook thread 10, whereby the thread hook thread 10 caught and caught by the thread hook thread catching portion 50 a of the movable cutter 50 can be moved to the edge portion 51 e using the fixed cutter 51. The movable cutter 50 is stably moved until the cutting position in sliding contact with the thread hook thread catching portion 50a. In addition, after each thread is cut by the movable cutter 50, When the sewing fabric W is taken out, the needle thread 20a, 20b can be pulled out slightly by the resistance when the sewing thread W is pulled out from the sewing fabric W, and the next sewing seam can be formed stably.

FIG. 14 is a block diagram showing the configuration of the control system of the horizontal-cylindrical double-loop suture sewing machine of the first embodiment, which includes the suture-prevention device H and the thread cutting device 5 as described above.

The front pedal signal 21a and back pedal signal 21b generated by the pedal switch 21, the needle position signal 22 when the needles 2a and 2b are near the top dead center, and the thread trimming signal 23 and the needle thread sending signal 24 are input to the control of the double loop sewing machine, respectively. Department 8.

On the other hand, the operation control signal is output from the control unit 8 to the line operation cylinder 32, the stopper cylinder 42, and the thread trimming cylinder 48, respectively. The thread hook 3 and the thread hook holding body 6 operate in the manner described above according to the operation control signals output from the control unit 8 to the line operation cylinder 32 and the stop cylinder 42. The thread trimming cylinder 48 is based on the thread cut output from the control unit 8. Signal 23 performs telescopic movements.

In addition, the operation control signal is output from the control unit 8 to the sewing machine motor 80, which is the driving source of the transmission rotary shaft, the work clamp cylinder 81 for raising and lowering the work clamp foot, and the needle thread 20a, 20b cut off in the following manner An air wiper 82, a conveyance reduction mechanism 83 that adjusts the conveyance amount of the sewing fabric, and a thread hook thread suppression mechanism 84 that suppresses the feeding of the thread hook 10 to the thread hook 1.

The conveyance reducing mechanism 83 changes the operation form of the conveying teeth in the conveying mechanism. For example, the operation path of the conveying teeth is inclined with respect to the needle plate 12 to shorten the protruding time of protruding to the needle plate P, thereby reducing the effect of the conveying teeth on the needle plate. The time when sewing the fabric on 12 or the length of the rod that circulates the conveying teeth is changed, thereby reducing the unit conveying pitch of the conveying teeth, thereby reducing Since the conveying amount of the sewing fabric is well known, such a conveying reduction mechanism 83 is omitted, so detailed illustrations and explanations are omitted.

The thread hook thread suppressing mechanism 84 includes: a thread tension disc which clamps the midway portion of the thread hook thread 10 which is fed to the thread hook 1; and an actuator which causes the thread tension disc to clamp the thread hook thread. Operate by increasing or decreasing the strength; increase the clamping strength of the thread tension disc to the hook wire and increase the resistance exerted on the hook wire 10, thereby suppressing the sending of the hook wire 10, such a hook wire The suppression mechanism 84 is also well known, so detailed illustrations and explanations are omitted.

The control unit 8 performs the hooking hook 3 in association with the sewing machine motor 80, the cloth presser cylinder 81, the blower thread reel 82, the conveyance reduction mechanism 83, and the thread hook thread suppression mechanism 84 after the completion of the sewing of the double loop stitching. With this operation, the anti-fracture operation and the thread trimming operation of the double loop suture are performed.

FIG. 15 is a timing chart showing the content of operations of the control section 8 for preventing blooming according to time. The control unit 8 is a computer having a CPU, a ROM, and a RAM. The anti-fracture action and the tangent action according to the timing chart of FIG. 15 are executed by a series of actions of the CPU based on the control program stored in the ROM.

FIGS. 16 to 20 are explanatory diagrams of the anti-flapping operation of the anti-flapping device H in the horizontal-cylindrical double-loop stitching sewing machine of the first embodiment, and show the hanging caused by the operation of the control unit 8 according to the timing chart of FIG. 15. The operation state of the thread hook 3 and the thread hook holding body 6.

When a sewing operator using a sewing machine finishes normal sewing, he stops the stepping operation of the pedal for driving the sewing machine, and then performs a fleece prevention operation. In this case, the pedaling operation is performed on the pedal. The pedal switch 21 is attached to the pedal, and outputs a front depression signal 21a during a forward depression operation, and outputs a depression signal 21b during a depression operation.

When the normal sewing is finished, at the time of S1 in FIG. 15, the pedal for driving the sewing machine has returned from the forward pedaling state to the neutral state, that is, when the forward pedaling signal 21 a and the pedaling signal 21 b are not output from the pedal switch 21. In any signal state, the control unit 8 refers to the needle position signal 22 given to the input side and outputs a stop command to the sewing machine motor 80. With this, the sewing machine is temporarily stopped in a state where the needles 2a and 2b are near the top dead center and the thread hook 1 has been advanced to the left.

Then, the control unit 8 waits until the pedal is depressed. When the step-back operation is performed at the time point of S2 in FIG. 15 and the step-back signal 21b is input to the input side, the control unit 8 first at the time of S3, for example, gives an operation start command to the conveyance reduction mechanism 83 to reduce the unit of the conveying teeth. The conveying pitch is such that the conveying amount (decrease) of the sewing fabric is smaller than the conveying amount during normal sewing, and then the fleece prevention operation described below is started. Furthermore, before the needle coils 20a2 and 20b2 are positioned closer to the entry and exit ends of the thread hook 1 than the lowering positions of the needles 2a and 2b by the hook 3, the setting is started by the above-mentioned conveying reduction mechanism. Period of conveying teeth in 83 to convey the sewing fabric with a small conveying amount (S3).

Furthermore, when the front pedal signal 21a is input from the pedal switch 21 to the control unit 8 again, the sewing operation returns to the normal sewing operation. Therefore, the sewing operator can perform the front pedal operation again to continue the normal sewing. . Further, in FIG. 15, the neutral state is maintained from the time point of S1 to the time point of S2, but it is not necessary to maintain such a neutral state. Generally, the operation of the pedal at the end of sewing can also be continuously transitioned from the forward pedaling state to Step back. In this case, when the neutral position is passed during the transition, it becomes a no-signal state in which neither of the front step signal 21a and the back step signal 21b is output, and the control unit 8 takes the no-sign state as the cause, as described above. As described, after the needles 2a and 2b are raised to the vicinity of the top dead center and the thread hook 1 has been advanced to the left, the anti-flapping operation is started.

Further, in the timing chart of FIG. 15, the pedal depression operation at the time of S2 is continued during the execution of the anti-flapping operation described below, but it is not necessary to continue this until the end of the anti-flapping operation. In this kind of stepping operation, even after the input of the stepping signal 21b is stopped, the fleece prevention operation is continuously performed by the action of the control unit 8.

FIG. 16 shows the state of the needles 2a, 2b, the thread hook 1, the thread hook 3, and the thread hook thread holding body 6 at the start of the fray prevention operation. The needles 2a and 2b are pulled out above the sewing fabric, and the sewing fabric is formed with a double loop sewing seam M by two needle threads 20a, 20b and one thread hook thread 10. The thread hook 1 is in a state where it goes to the lower side of the sewing fabric to the left and captures the stitch coils 20a2 and 20b2 formed by the stitches 2a and 2b. In this state, after the needle thread 20a, 20b and the thread hook thread 10 are cut, as shown in FIG. 24, a general suture completion portion is easily formed.

After the burst prevention operation is started, the control unit 8 first gives an operation command to the output-side line operating cylinder 32 at the time of S4 in FIG. 15. Thereby, the wire operating cylinder 32 moves from the extended state shown in FIG. 5 to the contracted state shown in FIG. 6, and the stopper member 14 is driven to move to the right direction, and the hanging hook 3 passes through the stopper member 14 and the connecting rod. 35. It swings around the support shaft 30 and moves from the standby position to the hanging position. At this time, the hook portion 3b at the front end of the thread hook 3 hooks a needle coil 20a1, and the rocking lever 9 in the stopper mechanism is pivoted clockwise with the fulcrum 90 as the center by the pressure of the spring 96. The engaging hook 9 a at the tip of the swing lever 9 is in a state capable of engaging with a part of the stopper member 14.

Then, the control unit 8 gives an operation instruction to the wire operation cylinder 32 which is slightly extended from the state shown in FIG. 6 to the state shown in FIG. 7, and the stopper member 14 is driven to move linearly to the left. When the wire operating cylinder 32 is slightly extended, the engaging hook 9 a at the front end of the swing lever 9 is engaged with a part of the stopper member 14. Thereby, the stopper member 14 is temporarily stopped Drive to the left. In a state in which the stopper member 14 is temporarily stopped and driven to move to the left in the above-described manner, as shown in FIG. 17, the hanging hook 3 stops moving between the standby position and the hanging position through the connecting rod 35. Position, the hook portion 3b at the front end holds the needle coil 20a2 at the above-mentioned holding position, and the thread hook thread holding body 6 enters and exits from the front side of the thread hook 1, and the front thread hook receiving portion 6a is held forward of the left needle drop position A线 爪 线 10。 Line hook line 10.

As described above, after the thread hook 3 and the thread hook holding body 6 are stopped at the above positions, the control unit 8 gives an operation command to the sewing machine motor 80 and the thread hook thread suppressing mechanism 84 at the time of S5 in FIG. 15. With reference to the needle position signal 22, the motion command is given after the needles 2a, 2b have descended until they are again raised to a position near the top dead center. Thereby, a sewing operation for one stitch of the sewing fabric is performed. By the operation of the conveyance reduction mechanism 83, the one-stitch sewing is performed with a smaller conveyance amount than during the normal sewing. In addition, by the operation of the thread hook thread suppressing mechanism 84, the one-stitch sewing is performed in a state where the feed of the thread hook 10 to the thread hook 1 is suppressed. Thereby, the sutured thread hook thread 10 is preferably tightened, and therefore, the anti-flapping effect described later can be improved.

As shown in FIG. 17, the thread hook 3 and the thread hook holding body 6 continue to hold the needle thread 20 a, 20 b and the thread hook 10 until the conveying movement of the sewing fabric is completed, and the needles 2 a and 2 b are held by the thread held by the thread hook 3 Loop 20a2 and capture the needle coil 20a2. At this time, as shown in FIG. 17, the thread hook thread 10 held by the thread hook thread holding body 6 is positioned across the front side of the left needle 2 a. Therefore, the needle 2a on the left side does not capture the thread hook thread 10, and the thread hook 10 is captured by the needle 2b on the right side only at the rear side of the thread hook 1.

The control unit 8 captures the timing of the needle coil 20a2 with the needle 2a on the left, that is, at a point after S6 in FIG. 15, and gives an operation command to the stopper cylinder 42 of the stopper mechanism. The stopper cylinder 42 extends, and the output lever 41 follows Eject the drive to the left. With this, as shown in FIG. 8, the above-mentioned shaking The lever 9 swings in the counterclockwise direction against the pressure of the rocking force of the spring 96. The engaging hook 9 a at the front end of the rocking lever 9 is released from a part of the stopper member 14, and the temporary stop of the stopper member 14 is released. Therefore, the stop of the stopper member 14 is released, and the wire operating cylinder 32 is extended to the maximum at the point of S6. Thereby, as shown in FIG. 18, the thread hanging hook 3 and the thread hook holding body 6 pass through the stopper member 14 and the connecting rod 35 and swing around the support shaft 30, and return to the standby position from the holding position. As a result, the holding of the needle coil 20a2 and the hook wire 10 is released.

Next, the thread hook 1 performs a rightward retreat operation as the needles 2a and 2b are lowered, and is pulled out from the needle coil 20a2 which has been captured. As the thread hook 1 is pulled out, as shown in FIG. 19, the right needle 2b catches the thread hook thread 10 as in normal sewing, and the left needle 2a catches the left needle coil 20a2. Of the state.

In this state, the hook 1 is shifted to the left, and the needles 2a, 2b are shifted to the up. As shown in FIG. 20, the left-hand thread hook 1 captures the stitch coils 20a2 and 20b2, and the rising stitches 2a and 2b are pulled out above the sewing fabric. Thereby, the needle thread 20a captured by the thread hook 1 performs a so-called self-series loop, that is, the needle thread 20a and the captured needle coil 20a2 are looped.

After the sewing operation of 1 needle, the sewing operation is ended when the needles 2a and 2b have risen to the vicinity of the top dead center and the thread hook 1 has reached the vicinity of the left advance end. Then, the control unit 8 stops the conveyance reduction mechanism 83 at the time of S7 in FIG. 15 and waits in this state until the thread cutting signal 23 is given. Next, at time S8 in FIG. 15, the control unit 8 is given a tangent signal 23 and then gives an operation command to the tangent cylinder 48 of the tangent device 5 to cause the tangent cylinder 48 to perform a predetermined operation. As a result, as shown in FIG. 11, the thread trimming device 5 is moved to the external position on the side of the needle drop positions A, A through the reciprocating drive movement mechanism 70, that is, the above-mentioned entry / exit position P1. Then, a tangent operation is performed. Hereinafter, this tangent operation will be described in detail based on FIG. 21.

First, as shown in FIG. 21 (a), after the stitching is completed, after the thread cutting device 5 is moved to the external position on the side closer to the needle drop position, that is, the above-mentioned entry / exit position P1, as shown in FIG. 21 (b), only The movable cutter 50 is driven to move in the direction of the arrow x (leftward movement) from the above-mentioned entry / exit position P1 to an outer position on the other side of the needle drop position. During the forward driving movement, the blade portion 50e of the movable cutter 50 sequentially hits the right needlework portion 20b1, the left needlework portion 20a1 protruding on the back side of the sewing fabric W, and the left and right needlework portions 20b1. , 20a1 is cut off at or near the needle drop position. By this cutting, each of the left and right needlework portions 20b1, 20a1 becomes a short remaining thread length from the back surface of the sewing fabric W to the passing position of the blade portion 50e of the movable cutter 50.

Next, as shown in FIG. 21 (c), the thread hook thread catching portion 50a on the front end side of the movable cutter 50 passes over the thread hook portion 10 between the vicinity of the front end of the thread hook 1 and the back side of the sewing fabric W, and then moves. The moving direction of the cutter 50 is immediately reversed. Next, as shown in FIG. 21 (d), the movable cutter 50 moves from the external position on the other side of the needle drop position to the entrance / exit position P1 and moves back (rightward) in the direction of arrow y. During the return driving movement, the thread hooking portion 10a protruding on the back side of the sewing fabric W is caught and caught by the thread hooking thread catching portion 50a. Next, the movable cutter 50 is further driven and moved back in the direction of the arrow y. As shown in FIG. 21 (e), the thread hook portion 10a captured by the thread hook thread capture portion 50a is fixed by the capture portion 50a and the fixed portion. The blade edge portion 51e of the cutter 51 is cut by sliding contact. At the time of this cutting, as shown in FIG. 12 (A), the edge portion 51e of the fixed cutter 51 is located at the position of the up and down movement path of the needle 2b on the right side. Therefore, as shown in FIG. 22, it remains in the sewing after cutting. The length of the thread hooking portion 10a on the back surface of the cloth W also becomes shorter.

Then, as shown in FIG. 21 (f), the needles 2a and 2b are moved upward to the needle plate 12, and the ends of the thread hook thread 10 held by the thread hook 1 are elastically clamped between the movable cutter 50 and the thread hook thread. Hold 件 52 之间。 Between members 52.

The thread-hook thread suppression mechanism 84 continues to operate until the thread-cutting operation as described above ends, and applies a predetermined tension to the thread-hook thread 10 extending from the front end of the thread hook 1 to the sewing fabric. Thereby, the thread hook thread catching part 50a at the front end of the movable cutter 50 can reliably catch and cut the tight thread hook thread 10.

After the above thread cutting operation is completed, the thread cutting device 5 moves to the retreat position P2 as shown in FIGS. 10 (A) and (B) through the reciprocating driving movement mechanism 70, and waits in an inclined posture that does not hinder the movement of the thread hook 1 Next sewing. On the other hand, the control unit 8 waits until the needle thread sending signal 24 is inputted. At the time of S9 in FIG. 15, the control unit 8 inputs the needle thread sending signal 24 and outputs an operation instruction to the hair dryer threader 82. This blower dial 82 is operated. The air blower 82 blows air, and the cut ends of the needle threads 20a and 20b connected to the needles 2a and 2b are raised. Then, at the time of S10 in FIG. 15, the control unit 8 outputs an operation command to the work clamp air cylinder 81 to operate the work clamp air cylinder 81 to raise the work clamp foot, thereby ending a series of fray prevention operations.

In the above-mentioned one-needle stitching operation for preventing blooming, as shown in FIG. 22, the thread hook thread 10 is formed in the stitch loop 20b2 on the right side of the back of the sewing fabric W at the end of the sewing seam M, and During the one-needle sewing operation, it is folded back before the right needle thread 20b pulled out on the back of the sewing fabric W, and it is pulled out again and cut by the final needle loop 20b2 on the right side.

On the other hand, the left needle thread portion 20a1 pulled out on the back side of the sewing fabric W during the sewing operation of one stitch for preventing fraying is formed in the final stitch loop 20a2 on the back surface of the sewing fabric W at the time of normal sewing. Then, the final needle coil 20a2 is self-stringed into a loop, thereby forming a single-loop stitching seam M. Therefore, the hook thread 10 is firmly held by the needle thread 20a and the final needle coil 20b2. As shown in FIG. 22, the press is restrained in a state where the holder is positioned between the last needle coil 20 b 2 on the left side and the needle coil 20 c formed once before. This restraint state is maintained regardless of the direction in which the force is applied to the thread hook thread portion 10a. Therefore, it is possible to prevent a unique hook thread from occurring in the double loop suture M.

Moreover, in the sewing operation of one stitch for preventing flaking, the conveying amount of the conveying teeth in the conveying reducing mechanism 83 for the sewing fabric is smaller than the conveying amount during normal sewing. Therefore, as shown in FIG. The pitch P of the stitching seam formed by the previous series of loops is smaller than the pitch P0 of the stitching seam formed by the previous series of loops. As a result, the pressing of the thread hook portion 10a between the left needle thread 20a and the left needle loop 20a2 is strengthened, and the stopping resistance increases. Therefore, when the state shown in FIG. 22 has been reached, it is possible to increase the multiplying effect of the stopping resistance of the thread hook 10 from the tandem loop portion and the reduction of the pitch P with the following stitching, as follows: The double loop stitching seam M is prevented from spreading, and the pitch P of the stitching seam is formed by the inter-series loops before self-stringing.

Furthermore, it is also possible to start from a stage before the sewing operation of the 1-needle for preventing fraying, specifically, since the needle coil 20a2 is located closer to the entry and exit ends of the needle hook 1 than the lowering position of the needle 2a by the needle hook 3 Beginning at least one and a half stitches before the side position (at the time of S3 in FIG. 15), the above-mentioned conveyance reduction mechanism 83 starts conveying with a small conveyance amount. In this case, the pitch of the stitching seam formed by the series-connected loops before the series-connected loops is also smaller than the pitch P of the stitching seam formed by the series-connected loops. Therefore, the stopping resistance of the hook wire 10 is further increased, thereby It is possible to more reliably prevent the suture seam M from spreading.

In a series of wire cutting operations described in FIG. 21, as shown in FIG. 21 (b), when only the movable cutter 50 is driven to move in the arrow x direction (leftward), the movable cutter 50 When cutting the left and right needle thread portions 20b1 and 20a1 in sequence with the blade portion 50e of 50, the needle thread pressing device 55 is operated to press the needle threads 20b and 20a, whereby the needle thread portions 20b1 and 20a1 at the time of cutting can be applied. By applying a certain tension, the needle thread portions 20b1 and 20a1 can be cut accurately and neatly at the needle drop positions A, A or the vicinity thereof.

As described above, according to the thread-cutting device 5 of the double-loop stitching sewing machine of the first embodiment, after a predetermined sewing operation (after the stitching is completed), the movable cutter 50 is moved from the outer side of the needle drop position to the other side. The outer position on the side is driven to move in a row, whereby the blade portion 5e of the movable cutter 50 can be pushed against the left and right needle thread portions 20b1 and 20a1 protruding on the back side of the sewing fabric W, and at the needle drop positions A, A, or The needle and thread portions 20b1 and 20a1 are cut and cut near the needle drop position. Therefore, the needle and thread portions 20b1 and 20a1 on the back of the sewing fabric W can be automatically cut to the following length, which does not damage the protection caused by the self-winding loop. The length of the blooming effect is a short remaining length that does not greatly exceed the level of the seam M of the sewing fabric W. As a result, the sutures are not frayed after the fleece is prevented, and it is possible to improve the completion and appearance of the stitched product as a whole.

In addition, when the movable cutter 50 is driven and moved from the outer position on the other side of the needle drop position A, A to the outer position on the other side, the movable cutter 50 is captured by the thread hook formed on the movable cutter 50. After the portion 50a catches and catches the thread hooking portion 10a protruding on the back side of the sewing fabric W, the fixed cutter 51 slides the thread hooking portion 10a by sliding contact with the thread hooking thread catching portion 50a, and the fixed cutter The edge portion 51e of the front end of the 51 is located within the range that does not enter the up and down reciprocating motion path of the right needle 2b, and is located closest to the needle drop position. Therefore, the sewing can be performed without exceeding the stitching seam M by a large margin. The remaining length of the thread hook portion 10a on the back of the cloth W is also automatically cut to a shorter remaining length.

Therefore, at the completion of sewing, no complicated and manual operations that are prone to deviations, such as the use of scissors, are required to cut the sewing fabric W to shorten the remaining length of the thread. The respective wire portions 20b1, 20a1, and 10a on the back side. Therefore, the manual operation for cutting the thread is not required, and the above-mentioned self-tandem loop is used to prevent flaking, and other steps such as reinforcing the seam are not required. Therefore, the sewing operation efficiency (productivity) in the continuous production of a large number of sewing products can be significantly improved. ). Therefore, it is possible to prevent the following situations, which can improve the completion and aesthetics of the finished sewing product as a whole. The above-mentioned situation refers to the damage to the sewing fabric due to scissors, etc., or the remaining length of the thread is cut due to the deviation of the cutting position. If the length is too short, the anti-flapping effect caused by the self-connecting loop will be impaired, and the stitching seam after the anti-flapping of the thread will open.

Next, a horizontal cylindrical double-loop sewing machine according to a second embodiment of the present invention will be described.

As shown in FIG. 23, the horizontal cylindrical double-loop sewing machine of the second embodiment differs from the first embodiment in that it has a tilted posture slightly reversed from that of the first embodiment to form a movable cutter in the thread cutting device 5. The configuration of the blade portion 50e of 50 is the same as that of the first embodiment. Therefore, descriptions and specific illustrations of configurations other than the above-mentioned configuration (the shape of the blade portion 50e of the movable cutter 50) different from the first embodiment are omitted.

In the horizontal cylindrical double-loop sewing machine of the second embodiment, when the movable cutter 50 in the thread cutting device 5 moves from the outer position on the other side (left) of the needle drop position A, A to the side (right) When the position is driven to move back (when moving from the state corresponding to FIG. 21 (c) to the state corresponding to FIG. 21 (d)), the blade portions 50e are sequentially abutted on the left and right sides of the protruding side of the sewing fabric W The needle thread portions 20a1 and 20b1 are pulled and cut at the needle drop positions A, A or the vicinity of the needle thread portions 20a1 and 20b1.

This second embodiment is similar to the first embodiment in that it does not impair the effect of preventing looping caused by self-stringing, and can not exceed the stitching seam M to a large extent, and will sew fabric. The needle thread portions 20a1, 20b1 and the thread hook portion 10a protruding on the back surface of W are automatically cut to a shorter remaining length. As a result, similarly to the first embodiment, it is possible to remarkably Improve the sewing work efficiency (productivity) when continuously producing a large number of sewing products, and do not damage the sewing fabric by scissors, etc., or damage the remaining length of the thread due to the deviation of the cutting position. The blooming effect can improve the completion and aesthetics of the finished sewing product as a whole.

Furthermore, in each of the embodiments described above, as the cutting edge portion 50e of the movable cutter 50, the cutting edge portion 20a1, 20b1 which is protruded on the back surface of the sewing fabric W has been described as being cut or pulled, However, it may be formed in a shape such that when the movable cutter 50 moves forward or backward, the blade portion 50e moves in contact with the sides of the needle thread portions 20a1 and 20b1, thereby wiping off from the side. Needlework portions 20a1 and 20b1.

In each of the above embodiments, it has been described that the thread hook thread holding body 6 is configured so as to be able to move in and out of the thread hook 1 integrally with the thread hook 3 in the needle thread holding mechanism. The thread hook holding body 6 can be constructed in a manner capable of moving closer to and away from the thread hook 1 in the above-mentioned needle thread holding mechanism. Moreover, it is not necessary to provide the hook-and-thread holding body 6.

Furthermore, in the first embodiment described above, a configuration has been described in which the thread hook 1 is moved in and out of the thread hook 1 and the thread hook receiving portion 6a at the front end holds the thread hook 10 in front of the needle drop positions A and A. The thread hook thread holding body 6, but it can also enter and exit on the rear side of the thread hook 1, and the thread hook receiving portion 6a at the front end holds the thread hook thread 10 at the rear of the needle drop position A, A to constitute the thread hook.线 住 体 6。 Line retaining body 6.

In addition, although the needle thread pressing device 55 described in the first embodiment is effective in reliably cutting the needle thread portions 20a1 and 20b1, the blade portion 50e of the movable cutter 50 may be formed as a sharp blade portion. The provision of the needle thread pressing device 55 is omitted.

In addition, in each of the above-mentioned embodiments, the installation of the anti-flapping device H has been described. The needle plate table 11 is divided into a left needle plate table section 11L and a right needle plate table section 11R. Thus, the assembling workability or ease of maintenance of the sewing machine shuttle bed section B is improved, but as before, As shown in FIG. 25 and FIG. 26 in the art, the needle plate base 11 in the fray prevention device H may be configured as a long object in the left-right direction.

In addition, in the above-mentioned embodiments, the double-needle horizontal-cylindrical double-loop sewing machine is applied, but it can also be applied to a single-needle horizontal-cylindrical double-loop sewing machine or a flat-type double-loop sewing machine.

Claims (5)

A double loop suture method that captures one or more needles under the needle plate by holding the needle thread and moving up and down by a thread hook capable of advancing and retracting in a direction slightly orthogonal to the up and down motion path of the needle The formed stitches are connected in series with each other by the hooks held by the hooks to form a double loop stitch on the sewing fabric conveyed on the needle board. The double loop stitch method is characterized by: After the above-mentioned thread hook is put in and out and the normal sewing is finished, a sewing operation including at least one stitch including the following steps is performed, whereby the needle loop is self-connected by the needle thread held by the needle, thereby preventing double loop stitching. The seam is opened, and the above-mentioned step means that the stitch coil captured by the thread hook is kept closer to the entry and exit end sides of the hook than the lowered position of the needle, and the hook wire is positioned closer to the lowered position of the needle. After the position on the front side, the feeding of the thread toward the hook is suppressed, and the state is maintained until the needle is lowered through the stitch coil captured by the hook. , And then release the position holding of the needle coil, and the needle is lowered by the needle coil; then, when the outer position on one side of the needle drop position in the needle board and the needle drop position on the other side can be released When the movable cutter moves back and forth between the two positions, the movable cutter is driven back and forth between the two positions from the position on one side of the needle drop position to the position on the other side of the other side. When moving, or when the movable cutter moves back from the external position on the other side to the position on the one side, the blade is formed at the needle drop position or the needle drop position by the blade portion formed on the movable cutter. Nearby cut or pull to cut the needle thread part protruding on the back side of the sewing fabric; and then, when the movable cutter moves from the position of the other side of the needle drop position to the position of the outer side of the one side, it is driven and moved back , Hooking the thread hooking portion protruding from the back side of the sewing fabric by the thread hooking thread catching portion formed on the movable cutter, and transferring the thread hooking portion to the edge portion of the fixed cutter The blade edge portion of the fixed cutter is disposed near the needle drop portion within a range that does not enter the up-and-down motion path of the needle. The sliding hook portion is cut by sliding contact; and the end portion of the cut wire hook is elastically clamped between the movable cutter and a wire hook clamping member disposed at a lower portion of the movable cutter. And wait for the next sewing. For example, the double-loop stitching method of the first scope of the patent application, in which the conveying movement of the sewing fabric has been stopped, or when the conveying movement is smaller than the conveying movement of the sewing fabric during ordinary sewing, The sewing operation of at least one stitch for the self-tandem loop is performed. A double loop sewing sewing machine comprising: one or a plurality of needles for holding a needle thread and moving up and down; a thread hook capable of holding the thread of a hook to advance and retreat in a direction slightly orthogonal to the vertical movement path of the needle, and During the movement, it captures the stitch formed by the needle under the needle plate; it can move back and forth between the outer position on the one side of the needle drop position and the position on the other side of the needle drop position in the needle plate. Driven by movement, using the hook thread held by the hook, the needle loop captured by the movement of the hook into and out of the loop is connected in series, thereby forming a double loop on the sewing fabric conveyed on the needle board. Stitching seam; The double loop stitching sewing machine includes a thread cutting device including a movable cutter and a fixed cutter, and a thread hook thread holding member. The movable cutter and the fixed cutter are cut after the double loop sewing seam is formed. The needle thread portion and the thread hook portion that protrude on the back side of the sewing fabric are elastically clamped at the ends of the cut thread hook between the thread hook holding member and the movable cutter. The double-loop sewing sewing machine is characterized by having a needle thread holding mechanism capable of approaching and moving away from the thread hook, and during the approaching motion, holding the stitch coil captured by the thread hook at a lower position than the needle It is closer to the entry and exit ends of the above-mentioned hooks; the hook hook thread holding body can move close to and away from the above-mentioned hooks, and when the approaching action is performed, the hooks extending from the above-mentioned hooks to the sewing thread are held At a position closer to the front side than the lowering position of the needle; the thread hook thread suppressing mechanism that suppresses the feeding of the thread toward the thread hook; and a control unit that operates with the needle and the thread hook, and the sewing fabric The movement of the needle thread holding mechanism and the thread hook thread holding body is controlled in accordance with the conveying movement of the sewing machine. The control unit sets the thread hook to the in and out position, and sets the needle to the raised position to end normal sewing. The sewing operation including at least one stitch including the following steps is performed to prevent the stitches of the stitches from being looped by the stitches held by the stitches. The operation of the double loop suture opening is to move the needle thread holding mechanism closer to the needle coil, to keep the needle coil closer to the entry and exit ends of the hook than the lowered position of the needle, and to keep the hook thread After the body is close to the hook and the thread of the hook is positioned more forward than the lowered position of the needle, the thread hook thread suppressing mechanism is started to suppress the feeding of the thread toward the hook, and maintain the The state is until the needle is lowered by the needle loop captured by the thread hook, and then the position holding of the needle loop is released, in cooperation with the lowering and rising of the needle, the forward and backward movement of the thread hook, and the conveying motion of the sewing fabric. The needle is lowered by the needle coil; a blade portion is formed on the movable cutter in the thread cutting device, and a wire hook catching portion is formed; after the anti-flapping operation, when the movable cutter is at the position where the needle is dropped, During the reciprocating driving movement between the position on the other side and the external position on the near side, the movable cutter moves from the needle drop position. When the position on one side is driven to move toward the external position on the other side, or when the movable cutter is driven and moved from the external position on the other side to the position on the one side, the blade portion At the needle drop position or near the needle drop position, cut or pull to cut the needle thread part protruding on the back side of the sewing fabric. When the movable cutter moves from the position on the other side of the needle drop position to the side closer to the needle, When the outer position is driven and moved back, the thread hook thread catching portion catches and catches the thread hook thread portion protruding on the back side of the sewing fabric, and each of the fixed cutter and the thread hook thread holding member in the thread cutting device is The front end portion is disposed close to the needle drop portion within a range that does not enter the up and down motion path of the needle; when the movable cutter moves from the position on the other side of the needle drop position to the outer position on the side closer to the needle drop position During the return driving movement, the sliding contact between the thread hook thread catching portion and the fixed cutter is used to cut off the portion captured by the thread hook thread catching portion and transferred to the front end portion of the fixed cutter. The thread hook thread portion is configured to elastically clamp an end portion of the cut thread hook thread between the movable cutter and the thread hook thread holding member, and wait for the next sewing. For example, the double-loop stitching sewing machine according to item 3 of the patent application, wherein the control unit is configured in such a manner that the conveying movement of the sewing fabric has been stopped, or the conveying movement of the sewing fabric is smaller than that during normal sewing When the conveying movement amount is conveyed, the sewing operation of the at least one stitch for the self-winding loop is performed. For example, the double-loop stitching sewing machine according to item 3 of the patent application further includes a needle thread pressing device, and when the needle thread portion is cut and cut by the blade portion of the movable cutter, the needle thread is held on the upper portion of the needle plate. .