WO2009113337A1 - Seam forming apparatus and sewing machine - Google Patents

Abstract

Disclosed is a seam forming apparatus which can perform fine adjustment of the width of a seam from zero by simple manual operation. The seam forming apparatus (1) comprises a needle clamp member (2) provided at the lower portion of a needle bar (52), and two needles (3, 4) secured to the needle clamp member (2). The needle clamp member (2) comprises a fixing member (11) fixed to the needle bar (52), and a rotating member (21) which is rotatably provided on the fixing member (11) and to which the two needles (3, 4) are secured. The rotating member (21) so rotates as to change the positions of the two needles (3, 4), whereby the width of a seam formed by the two needles (3, 4) can be adjusted.

Description

Seam forming device and sewing machine

The present invention relates to a stitch forming device that adjusts the interval between stitches formed by the needle thread of two needles by changing the position of the needle, and a sewing machine using the stitch forming device.

Some conventional sewing machines include a seam forming device that forms a seam substantially parallel to a sewing product such as a cloth or leather by two needles (for example, Patent Documents 1, 2, and 3). The width of the seam formed by these two needles is 3.2 mm or more for thin objects and 4.8 mm or more for thick objects (for example, Non-Patent Document 1).
JP-A-3-236895 Japanese Utility Model Publication No. 3-103085 Japanese Utility Model Publication No. 54-47568 Brother Industries, Ltd., product catalog “2-needle lockstitch direct drive sewing machine”, page 11, [online], May 2007, [March 4, 2008 search], Internet <URL: http: / /pub.brother.co.jp/pub/jp/j-ism/pdf/t8420b.pdf>

The conventional seam forming device attached to the sewing machine has a problem that the width of the seam can be changed, but the width of the seam cannot be finely adjusted from zero. For example, in the invention described in Patent Document 1, a needle cub single body with a needle attached is fixed to both sides of the needle cub base with screws, but the needle cub single body is changed left and right to change the width of the seam. It is like that. Therefore, as shown in FIGS. 11A and 11B, the invention described in Patent Document 1 can only change the widths of the stitches P1 and P2 into two types (D1 and D2), Cannot be finely adjusted from 0. Moreover, the work to change the width of the seam is extremely troublesome because the needle cub base on both sides is removed from the needle cub base by loosening the screw, and the needle cub single body is replaced with left and right, and then the screw is tightened to fix it to the needle cub base. There was a problem that it took.

In the invention described in Patent Document 2, the auxiliary needle holder is rotatably attached to the needle body. A needle is attached to the needle holder body and the auxiliary needle holder. In order to change the width of the seam, loosen the set screw to allow the auxiliary needle holder to rotate, rotate the auxiliary needle holder to a predetermined position, and then tighten the set screw to fix the auxiliary needle holder. Thus, the invention described in Patent Document 2 can change the width D3 of the seams Q1, Q2 to the width D4 as shown in FIGS. 12 (a) and 12 (b). Cannot be fine-tuned from zero. Further, only the needle attached to the auxiliary needle holder can be rotated to change the position of the seam Q2. However, since the needle attached to the main needle body is fixed, the position of the seam Q1 is changed. There was a problem that it was not possible.

Further, in the invention described in Patent Document 3, the attachment members attached with the needles are fixed to the both sides of the support frame with screws. However, in order to change the width of the seam, the screws are loosened and the attachment members are slid. The mounting members on both sides are slid in the left-right direction, and then the screws are tightened to fix the mounting members to the support frame. In this way, the invention described in Patent Document 3 can change the width D5 of the seams R1, R2 to the width D6 or D7 as shown in FIGS. 13 (a), (b), and (c). Yes, but the seam width cannot be finely adjusted from zero. In addition, the work of changing the width of the seam is very troublesome because the mounting members on both sides are loosened, then the mounting members are slid to a predetermined position, and the screws are tightened to fix the mounting members to the support frame. There was a point.

When using a current sewing machine that forms a seam with two needles and performing ground stitching on thick materials such as leather and canvas, it is necessary to make the two seams as close as possible due to the strength of the sewing. This is because, in the case of a product that applies force in a direction that always expands from the inside to the outside, such as a leather ball, if the distance between the two seams is wide, no force is equally applied to both seams. This is because a force is applied only to the outer seam without applying a force to the inner seam, and the outer seam may be loosened. However, as described in Non-Patent Document 1, the current sewing machine that forms a seam with two needles has a minimum seam width of 3 depending on the thickness of the gauge to which the needle is attached, the outer diameter of the needle itself, and the like. This minimum width is the current standard. Therefore, the current sewing machine has a problem that the width of the seam cannot be reduced to zero.

In addition, as described in Non-Patent Document 1, a current sewing machine that forms a seam with two needles needs to change the gauge to which the needle is attached in order to change the needle width (the width of the seam). However, there is a problem that the operation of exchanging the gauge is extremely troublesome and the needle width (seam width) cannot be easily changed. Furthermore, the current sewing machine changes the needle width (seam width) by changing the gauge so that, for example, the next of 3.2 mm becomes 4.8 mm, so it is set to 4 mm, for example. However, there was a problem that stepless fine adjustment was not possible.

The present invention has been devised in view of the above problems, and a first object of the invention is to provide a seam forming apparatus capable of finely adjusting the width of a seam from 0 to steplessly by a simple manual operation. And It is a second object of the present invention to provide a sewing machine provided with the stitch forming device.

A seam forming apparatus according to claim 1 of the present application is a seam forming apparatus that is attached to a needle bar of a sewing machine and forms a seam substantially parallel to a sewing direction by two needles in order to achieve the first object. The needle retaining member is provided at a lower portion of the needle bar and two needles attached to the needle retaining member. The needle retaining member is fixed to the needle bar, and is rotated with respect to the fixing member. And a pivoting member to which the two needles are attached. The pivoting member changes the position of the two needles by pivoting, and a seam formed by the two needles. The width can be adjusted.

In order to achieve the second object, a sewing machine according to claim 2 of the present invention is a sewing machine including the seam forming device according to claim 1, wherein the sewing machine includes a feed dog that feeds a sewing product in an anti-sewing direction. And a pair of elongated holes that are inserted into the lower feed member at any rotation position of the two needles in accordance with the rotation of the two needles. And

In order to achieve the second object, the sewing machine according to claim 3 of the present invention has an upper feed member that feeds a sewn product with the lower feed member and feeds it in the counter-sewing direction. A pair of elongated holes are formed so that the two needles are inserted at any rotation position of the two needles in accordance with the rotation of the two needles.

In order to achieve the second object, the sewing machine according to claim 4 of the present application includes a pair of horizontal hooks respectively corresponding to the two needles, and the pair of horizontal hooks rotates the corresponding needles. It is arranged according to the position, and is configured to crawl only the loop of the needle thread formed by the corresponding needle.

In order to achieve the second object, the sewing machine according to claim 5 of the present application partitions the pair of long holes in the lower feed member, and a loop of needle threads formed on one long hole side is the other. A partition member is provided to prevent the needle thread loop formed on the long hole side and the other long hole side from projecting to the one long hole side.

The seam forming device according to the present invention forms a seam substantially parallel to the sewing direction by the needle thread of two needles. The two seams extending in parallel are formed symmetrically on both sides of the center line formed so as to extend the rotation center of the rotation member in the sewing direction. When the rotating member is rotated to one side, one needle is arranged on the center line at the front part in the sewing direction, and the other needle is arranged on the center line at the rear part in the sewing direction, the stitch formed by one needle Then, the seam formed by the other needle overlaps to sew on the center line, and the width of the pair of seams becomes zero. When the rotation member is rotated to the other side, one needle is arranged away from the center line at the front part in the sewing direction, and the other needle is arranged away from the center line at the rear part in the sewing direction, a pair of needles Will sew symmetrical positions on both sides of the center line, and the seam formed by one needle and the seam formed by the other needle will be separated from each other and extend substantially in parallel, creating a gap between the pair of seams. . As described above, the seam forming device according to the present invention can gradually increase the width of the seam formed by the pair of needles steplessly from 0 by rotating the rotating member. The effect is that fine adjustment is possible. The seam forming device according to the present invention can greatly improve the strength of sewing by setting the width of the seam to substantially zero, and forms a decorative seam by gradually changing the width of the seam steplessly. It is possible to provide various seams.

The sewing machine according to the present invention is provided with a stitch forming device having the adjustment function described above, and is long enough to insert two needles into the upper feed member and / or the lower feed member that feed the sewing product on which the stitch is formed. Since a pair of holes are formed, as described above, even if the position of the needle is changed by the rotating member, the needle always passes through the long hole, so that the needle sewing operation is not hindered. There is an effect that it can be performed smoothly.

The sewing machine according to the present invention includes a pair of horizontal hooks corresponding respectively to the two needles, and the pair of horizontal hooks is configured to receive only a loop of a needle thread formed by the corresponding needles. Therefore, it is possible to reliably carry out that the sword tip of one horizontal hook catches the loop of one needle thread and the sword tip of the other horizontal hook catches the loop of the other needle thread. Accordingly, in the sewing machine according to the present invention, the sword tip of one horizontal hook does not crawl the other needle thread loop, and the sword tip of the other horizontal hook does not crawl the one needle thread loop. There is an effect that the seam can be reliably formed.

In the sewing machine according to the present invention, since the lower feeding member is provided with a partition member for partitioning the pair of long holes, the loop of the needle thread formed on one long hole side protrudes to the other long hole side. And the loop of the needle thread formed on the other long hole side does not protrude to the one long hole side. Therefore, it is possible to surely prevent the sword tip of one horizontal hook from hitting the loop of the other needle thread, and to reliably prevent the sword tip of the other horizontal hook from hitting the loop of one needle thread. There is.

Embodiments of a sewing machine according to the present invention will be described with reference to FIGS. FIG. 1 is an overall perspective view of a seam forming device used in a sewing machine. 2A and 2B are explanatory views for explaining a fixing member of the needle retaining member, wherein FIG. 2A is a left side view, FIG. 2B is a front view, FIG. 2C is a right side view, and FIG. FIGS. 3A and 3B are explanatory views for explaining a rotating member of the needle retaining member, wherein FIG. 3A is a left side view, FIG. 3B is a front view, FIG. 3C is a right side view, and FIG. . 4A and 4B are explanatory views for explaining an upper feed member of the sewing product, in which FIG. 4A is a left side view, FIG. 4B is a front view, FIG. 4C is a plan view, and FIG. . FIG. 5 is an explanatory view for explaining a lower feed member of a sewing product, wherein (a) is a plan view, (b) is a front view, (c) is a bottom view, (d) is a left side view, and (e). Is a right side view. FIG. 6 is an explanatory diagram for explaining the rotation trajectory of the upper feed member, the lower feed member, and the needle. FIG. 7 is an explanatory diagram for explaining the positional relationship between a pair of horizontal hooks and two needles. FIG. 8 is an explanatory view of a lower feed member to which a partition member is attached, in which (a) is a front view and (b) is a bottom view. FIG. 9 is an explanatory diagram of the stitches sewn by the stitch forming device according to the present invention. FIG. 10 is a front view of a seam actually sewn by the sewing machine according to the present invention, where (a) is a front view of the seam formed with different needle threads, and (b) is formed with the same needle thread. The front view of a seam, (c) is a front view of a seam in which the pitch is increased with different needle threads.

As shown in FIG. 1, a seam forming device 1 is attached to a needle bar 52 of a sewing machine 51 and forms seams 3a, 4a substantially parallel to a sewing direction X by two needles 3, 4. It comprises a needle retaining member 2 provided below the needle bar 52 and two needles 3 and 4 attached to the needle retaining member 2. The needle retaining member 2 includes a fixing member 11 fixed to the needle bar 52 and a rotating member 21 that is rotatably provided on the fixing member 11 and attaches the two needles 3 and 4. Yes. The rotating member 21 can change the position of the two needles 3 and 4 by rotating, and can adjust the width of the seams 3 a and 4 a formed by the two needles 3 and 4.

As shown in FIG. 9 (a), the stitch forming device 1 forms the stitches 3a and 4a substantially parallel to the sewing direction X by the needle threads of the two needles 3 and 4. The two seams 3a and 4a extending substantially in parallel are formed symmetrically on both sides of the center line A formed so as to extend the rotation center of the rotation member 21 in the sewing direction. As shown in FIG. 9 (b), the rotating member 21 is rotated in one direction so that one needle 3 is placed on the center line A in the front part of the sewing direction X and the other needle 4 is in the rear part in the sewing direction X. Are placed on the center line A, the seam 3a formed by one needle 3 and the seam 4a formed by the other needle 4 overlap to sew on the center line A, and a pair of The width of the seams 3a, 4a is zero.

As shown in FIG. 9A, the rotation member 21 is rotated to the other side, one needle 3 is arranged away from the center line A in the front part of the sewing direction X, and the other needle 4 is sewn. When spaced apart from the center line A at the rear in the direction X, a pair of needles 3 and 4 sew symmetrical positions on both sides of the center line A, and a stitch 3a formed by one needle 3; The seam 4a formed by the other needle 4 is separated and extends substantially in parallel, and a gap is formed between the pair of seams 3a and 4a. Thus, the seam forming device 1 can gradually widen the width of the seams 3a and 4a formed by the pair of needles 3 and 4 step by step from 0 by rotating the rotating member 21. Fine adjustment of seam width is possible. The seam forming device 1 can greatly improve the sewing strength by making the widths of the seams 3a and 4a substantially zero, and by changing the widths of the seams 3a and 4a steplessly step by step. Various seams can be provided.

The sewing machine 51 includes the above-described stitch forming device 1, and includes an upper feed member 61 that feeds a sewing product in an anti-sewing direction (Y direction) and a lower feed member 71 that includes feed teeth 76 and 77, and the upper feed member 61 and the lower feed member 71 are formed with a pair of long holes 68, 78, 69, 79 for inserting the two needles 3, 4, respectively. In the sewing machine 51, even if the position of the needles 3, 4 is changed by the rotating member 21, the needles 3, 4 always pass through the long holes 68, 78, 69, 79 and hinder the sewing work of the needles 3, 4. Therefore, the stitching operation of the needles 3 and 4 can be performed smoothly.

As shown in FIG. 7, the sewing machine 51 includes a pair of horizontal hooks 81 and 82 corresponding to the two needles 3 and 4, respectively. 4 is arranged in accordance with the rotational position of 4, and is configured to receive only the loop of the needle thread formed by the corresponding needles 3 and 4. The sewing machine 51 can surely perform that the sword tip of one horizontal hook 81 crawls one needle thread loop and the sword tip of the other horizontal hook 82 crawls the other needle thread loop. Accordingly, the sewing machine 51 has a pair of seams 3a because the sword tip of one horizontal hook 81 does not crawl the other needle thread loop, and the sword tip of the other horizontal hook 82 does not crawl one needle thread loop. , 4a can be reliably formed.

As shown in FIG. 8, the sewing machine 51 partitions the pair of long holes 78, 79 from the lower feed member 71, and the needle thread loop formed on one long hole 78 side is on the other long hole 79 side. In addition, a partition member 85 is provided to prevent the needle thread loop formed on the other long hole 79 side from projecting to the one long hole side 78. By this partition member 85, the sewing machine 51 reliably prevents the sword tip of one horizontal hook 81 from catching the other needle thread loop, and the sword tip of the other horizontal hook 82 catches the one needle thread loop. Can be reliably prevented.

Further, the stitch forming device 1 will be described in detail. The stitch forming device 1 includes a needle retaining member 2 and two needles 3 and 4. The needle retaining member 2 includes a fixing member 11 that is fixed to the needle bar 52 and a rotating member 21 that is rotatably provided on the fixing member 11 and to which the two needles 3 and 4 are attached. The

As shown in FIG. 2, the fixing member 11 includes a fixed shaft 12 and an attachment body 13 provided continuously with the lower end of the fixed shaft 12. A male screw portion 15 is provided on the upper portion of the fixed shaft 12. The attachment body 13 is formed in a hexahedron shape, and a bearing hole 17 is formed in the lower surface 16 thereof. Further, a female screw hole 19 communicating with the bearing hole 17 is formed on the side surface 18 of the attachment body 13.

As shown in FIG. 3, the rotating member 21 includes a rotating shaft 22 and a holding body 25 that is connected to the lower end of the rotating shaft 22. The rotating shaft 22 is provided with flanges 23 and 24 at an upper portion and a lower portion. The holding body 25 is formed in a hexahedral shape, and includes a front surface 26, a right side surface 27, a left side surface 28, a back surface 29, an upper surface 30, and a lower surface 31. The rotating shaft 22 has a lower end connected to the upper surface 30 of the holding body 25.

Mounting holes 32 and 33 for mounting the needles 3 and 4 are formed on the lower surface 31 of the holding body 25. A line connecting the centers of the mounting holes 32 and 33 is substantially parallel to the right side surface 27. A female screw hole 35 communicating with the mounting hole 32 is formed on the right side surface 27 of the holding body 25, and a female screw hole 36 communicating with the mounting hole 33 is further formed.

A positioning hole 37 communicating with the mounting hole 32 and penetrating the right side surface 27 and the left side surface 28 is formed immediately above the female screw hole 35. A positioning hole 38 communicating with the mounting hole 33 and penetrating the right side surface 27 and the left side surface 28 is formed immediately above the female screw hole 36. A protruding piece 40 is formed at the lower end of the front face 26. A guide hole 41 for guiding the needle thread is formed in the protruding piece 40. Similarly, a protruding piece 43 is formed at the lower end of the left side surface 28. The protruding piece 43 is also provided with a guide hole 45 for guiding the needle thread.

As shown in FIG. 1, the seam forming device 1 is configured by rotatably attaching a rotating member 21 to a fixed member 11. When the rotating shaft 21 is inserted into the bearing hole 17 of the fixing member 11 and the hexagon socket head bolt 20 is screwed into the female screw hole 19 of the fixing member 11, the tip of the bolt 20 is connected to the rotating shaft 22. It enters between the flanges 23 and 24 and is attached to the fixing member 11. The rotating member 21 is restricted from moving up and down within a range in which the flanges 23 and 24 abut against the tip of the hexagon socket head cap bolt 20. When the hexagon socket head bolt 20 is further screwed in, the rotating member 21 is fixed to the fixing member 21 because the tip of the bolt 20 is pressed against the rotating shaft 22.

The seam forming device 1 is fixedly attached to the needle bar 52 of the sewing machine 51 by screwing the male screw part 15 of the fixed shaft 12 of the fixing member 11 into the female screw part of the needle bar 52 of the sewing machine 51. When the bases of the needles 3 and 4 are inserted into the mounting holes 32 and 33 of the rotating member 21 and the hexagon socket bolts 34 and 34 are screwed into the female screw holes 35 and 36 of the rotating member 21, Since the tips of 34 and 34 are pressed against the bases of the needles 3 and 4, they are fixed to the rotating member 21.

The sewing machine 51 has an upper feed member 61 and a lower feed member 71 that feed a sewing product in the anti-sewing direction (Y direction) during a sewing operation. As shown in FIG. 4, the upper feed member 61 is formed in a substantially L shape, and includes a pressing shaft portion 62, an upper feeding plate 63 provided at a substantially right angle at the lower end of the pressing shaft portion 62, and an upper feeding plate 63. And an inclined piece 65 formed at the tip of the head. The pressing shaft portion 62 has an insertion hole 66 formed at the upper end and a screw hole 67 communicating with the insertion hole 66 on the upper side surface. The upper feed plate 63 is formed with long holes 68 and 69 through which the needles 3 and 4 are inserted. The peripheral edges of the long holes 68 and 69 are chamfered.

As shown in FIG. 1, the upper feed member 61 is fixedly attached to a support shaft 53 that is suspended so as to be substantially parallel to the needle bar 52 of the sewing machine 51. That is, an insertion shaft is formed at the lower end of the support shaft 53, the insertion shaft is inserted into the insertion hole 66 of the pressing shaft portion 62, and a bolt (not shown) is screwed into the screw hole 67, so that the bolt The tip is pressed against the insertion shaft of the support shaft 53, and the upper feed member 61 is fixed to the support shaft 53 so as not to rotate. The upper feed plate 63 is configured to press the sewing product against the lower feed plate 72 of the lower feed member 71 when the needles 3 and 4 are pushed down during the sewing operation (downward movement) of the sewing product. Further, the needles 3 and 4 move backward (sewing direction Y) in the same manner as the upper feed plate 63 during the sewing operation of the sewing product.

As shown in FIG. 5, the lower feed member 71 includes a lower feed plate 72, an attachment leg 73 provided at the lower front portion of the lower feed plate 72, and an attachment arm 74 provided at the lower rear portion of the lower feed plate 72. Consists of. The lower feed plate 72 has feed teeth 76 and 77 formed at the front and rear portions with the intermediate portion 75 interposed therebetween. Long holes 78 and 79 through which the needles 3 and 4 are inserted are formed in the intermediate portion 75. The long holes 78 and 79 are formed in substantially the same shape as the long holes 68 and 69 of the upper feed member 61.

As shown in FIG. 1, the lower feed member 71 is attached to a mechanism portion interlocking with the needles 3 and 4 so that the lower feed plate 72 is disposed in the opening 55 formed in the needle plate 54. The arm 74 is fixed. The lower feed plate 72 is configured to press the sewing product against the upper feed plate 63 of the upper feed member 61 when the needles 3 and 4 are pushed up during the sewing operation (downward movement) of the sewing product. Further, the needles 3 and 4 move rearward (sewing direction Y) in the same manner as the lower feed plate 72 during the sewing operation of the sewing product.

As shown in FIG. 6, when the upper feed member 61 and the lower feed member 71 are attached to the sewing machine 51, the long hole 68 located in front of the upper feed member 61 (X direction) and the front of the lower feed member 71 are located. The long hole 78 faces, and the long hole 69 located behind the upper feed member 61 and the long hole 79 located behind the lower feed member 71 face each other. As described above, the upper feed member 61 and the lower feed member 71 perform the operation of feeding the sewing product, so that the long hole 68 of the upper feed member 61, the long hole 78 of the lower feed member 71, and the upper feed member 61 are moved. The long hole 69 and the long hole 79 of the lower feed member 71 always coincide with each other during the sewing operation of the needles 3 and 4. As described above, the needles 3 and 4 rotate about the rotation shaft 22, but the needle 3 passes through the long holes 68 and 78 regardless of the position of rotation, and the needle 4 is the long hole 69. , 79 is inserted. The needles 3 and 4 also move backward in synchronization with the upper feed member 61 and the lower feed member 71 during the sewing operation.

As shown in FIG. 7, the sewing machine 51 is provided with horizontal shuttles 81 and 82 corresponding to the needles 3 and 4, respectively. The horizontal hook 81 corresponding to the needle 3 positioned forward in the sewing direction (X direction) is arranged in front of the horizontal hook 82 corresponding to the needle 4 positioned rearward in the sewing direction (X direction). The horizontal hook 81 is arranged in accordance with the rotation position of the needle 3 so that only the loop of the needle 3 is picked up regardless of the position of the movement of the needle 3. Similarly, the horizontal hook 82 is arranged in accordance with the rotational position of the needle 4 so that only the loop of the needle 4 is picked up no matter where the needle 4 moves.

A partition member 85 may be provided between the horizontal hooks 81 and 82. By this partition member 85, it is possible to avoid the possibility that the horizontal hook will crawl the loop of the needle that does not correspond. For example, the horizontal hook 81 is originally designed to pick up only the loop of the needle thread of the needle 3, but if the loop of the needle thread of the needle 4 protrudes for a long time for some reason, There is a possibility of hitting the loop. However, since the loop of the needle thread of the needle 4 does not protrude to the position where the horizontal hook 81 crawls due to the partition member 85, the horizontal hook 81 does not crawl the loop of the needle thread of the needle 4. Of course, the partition member 85 prevents the needle thread loop of the needle 3 from protruding to the position where the horizontal hook 82 crawls, so that the horizontal hook 82 does not crawl the needle thread loop of the needle 3.

The partition member 85 is formed of an elastic plate and is provided on one side of the sewing machine 51, but it is needless to say that the partition member 85 may be provided directly on the lower feed member 71 as shown in FIG. Further, the partition member 85 may not have elasticity, and may be integrally formed with the same material as the lower feed member 71.

The seam forming device 1 attached to the sewing machine 51 is a simple operation of loosening the hexagon socket head cap bolt 20 so that the rotating member 21 can be rotated, and the rotating member 21 is rotated to move the positions of the needles 3 and 4. The stitch width can be finely adjusted. After this fine adjustment, the hexagon socket head cap screw 20 is tightened to fix the rotating member 21 and set the positions of the needles 3 and 4. Since this fine adjustment can be performed while the needle thread is passed through the needles 3 and 4 during the sewing operation, for example, as shown in FIG. 10, the width of the seam can be continuously changed. In the conventional sewing machine, when changing the stitch width, the needle thread must be removed from the needle and the gauge must be replaced. Therefore, the stitch width cannot be changed continuously.

The stitch forming device 1 attached to the sewing machine 51 can improve the sewing strength by setting the width of the stitches to zero. In addition, decorative stitches can be performed by widening the stitch width. Furthermore, as shown in FIG. 10 (a), a seam formed with different needle threads, as shown in FIG. 10 (b), a seam formed with the same needle thread, as shown in FIG. 10 (c), Various seams can be formed, such as seams having pitches expanded with different needle threads.

The seam according to the present invention can be used for cloth products such as clothes and leather products such as bags.

1 is an overall perspective view of a seam forming device used in a sewing machine according to the present invention. It is explanatory drawing explaining the fixing member of a needle holder. It is explanatory drawing explaining the rotation member of a needle holder. It is explanatory drawing explaining the upper feed member of a sewing product. It is explanatory drawing explaining the lower feed member of a sewing product. It is explanatory drawing explaining the rotation track | orbit of an upper feed member, a lower feed member, and a needle | hook. It is explanatory drawing explaining the positional relationship of a pair of horizontal shuttle and two needles. It is explanatory drawing of the lower feed member to which the partition member was attached. It is explanatory drawing of the seam sewn by the seam formation apparatus which concerns on this invention. It is a front view of the seam actually sewn by the sewing machine according to the present invention. It is explanatory drawing of the seam sewn by the conventional sewing machine. It is explanatory drawing of the seam sewn by the conventional sewing machine. It is explanatory drawing of the seam sewn by the conventional sewing machine.

Explanation of symbols

A Center line X Sewing direction Y Feeding direction 1 Seam forming device 2 Needle retaining member 3 Needle 3a Seam 4 Needle 4a Seam 11 Fixing member 12 Fixed shaft 13 Mounting body 15 Male thread portion 16 Lower surface 17 Bearing hole 18 Side surface 19 Female screw hole 20 Hexagon socket head cap bolt 21 Rotating member 22 Rotating shaft 23 Flange 24 Flange 25 Holding body 26 Front surface 27 Right side surface 28 Left side surface 29 Back surface 30 Upper surface 31 Lower surface 32 Mounting hole 33 Mounting hole 34 Hexagon socket head bolt 35 Female screw hole 36 Female Screw hole 37 Positioning hole 38 Positioning hole 40 Projection piece 41 Guide hole 43 Projection piece 45 Guide hole 51 Sewing machine 52 Needle bar 53 Support shaft 54 Needle plate 55 Opening 61 Upper feed member 62 Press shaft portion 63 Upper feed plate 65 Inclined piece 66 Difference Insert hole 67 Screw hole 68 Long hole 69 Long hole 71 Lower feed member 72 Lower feed plate 73 Mounting leg 74 Mounting arm 75 Intermediate part 76 Feed dog 77 Feed dog 78 Long hole 79 Long hole 81 Horizontal hook 82 Horizontal hook 85 Partition member

Claims (5)

A seam forming device that is attached to a needle bar of a sewing machine and forms a seam substantially parallel to the sewing direction by two needles,
A needle retaining member provided at the bottom of the needle bar;
It consists of two needles attached to the needle retaining member,
The needle retaining member is composed of a fixing member fixed to the needle bar, and a rotating member that is rotatably provided on the fixing member and attaches the two needles.
The seam forming apparatus characterized in that the turning member can change the position of two needles by turning to adjust the width of a seam formed by the two needles. A sewing machine comprising the seam forming device according to claim 1, comprising a lower feed member having a feed dog that feeds a sewn product in an anti-sewing direction,
A sewing machine according to claim 1, wherein a pair of elongated holes are formed in the lower feed member so that the two needles are inserted at any rotation position of the two needles in accordance with the rotation of the two needles. Having an upper feed member that sandwiches the sewing product with the lower feed member and sends it in the anti-sewing direction;
3. The upper feed member is formed with a pair of elongated holes that are inserted in any rotation position of the two needles in accordance with the rotation of the two needles. The described sewing machine. A pair of horizontal hooks respectively corresponding to the two needles;
The pair of horizontal hooks are arranged in accordance with the rotation positions of the corresponding needles, and are configured to receive only the loop of the needle thread formed by the corresponding needles. The described sewing machine. The lower feed member partitions the pair of long holes, and a needle thread loop formed on one long hole side is formed on the other long hole side and the needle thread formed on the other long hole side. The sewing machine according to claim 4, wherein a partition member is provided to prevent the loop from projecting to the one long hole side.

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