The present invention relates to a seam formed by needle threads of two needles, less likely to be slackened and raveled, and having a novel structure and to a device and a method for forming the seam.
Conventionally, as shown in
Patent Document 1: Japanese Patent No. 3673601
The conventional seam A has the chain seams a1 and the lock seams a2 on the same straight line. Therefore, the needle forming the chain seams a1 and the needle forming the lock seams a2 are disposed on the same straight line along the sewing direction T. A pitch width P1 of the needle forming the chain seam a1 needs to be longer than an interval P2 between the needle for forming the chain seams a1 and the needle for forming the lock seams a2 so as to form the seam A. Therefore, the seam A needs to be set in consideration of a positional relationship between the needle for forming the chain seams a1 and the needle for forming the lock seams a2, which takes a lot of trouble. Moreover, in the conventional seam A, the lock seam a2 merely pulls the chain seam a1 to a front face side (upward) of a sewing material for tightening and therefore tightening force and resisting force for preventing slackening and raveling are slightly weak.
The invention of the present application has been made in view of the above problems and it is a first object of the invention to provide a seam without trouble of considering a positional relationship between a needle for forming chain seams and a needle for forming lock seams and with increased tightening force and resisting force for drastically preventing slackening and raveling. It is a second object to provide a seam forming device for forming the seam. It is a third object to provide a seam forming method for forming the seam.
To achieve the first object, a seam according to a first aspect of the present application is a seam formed by two needles juxtaposed in a substantially perpendicular direction to a sewing direction. The seam includes chain seams and lock seams formed by needle threads respectively passed through the two needles. A loop of the needle thread forming the chain seam is passed through a loop of the needle thread forming the lock seam, a stitch is tightened, and a loop of the needle thread forming the chain seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam.
To achieve the first object, a seam according to a second aspect of the present application is a seam formed by two needles juxtaposed in a substantially perpendicular direction to a sewing direction. The seam includes chain seams and lock seams formed by needle threads respectively passed through the two needles. A loop of the needle thread forming the chain seam is passed through a loop of the needle thread forming the lock seam, a stitch is tightened, and a loop of the needle thread forming the lock seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam.
To achieve the first object, a seam according to a third aspect of the present application is a seam formed by two needles juxtaposed in a substantially perpendicular direction to a sewing direction. The seam includes chain seams and lock seams formed by needle threads respectively passed through the two needles. A loop of the needle thread forming the chain seam is passed through a loop of the needle thread forming the lock seam, a stitch is tightened, and a loop of the needle thread forming the chain seam and a loop of the needle thread forming the lock seam located on a downstream side in the sewing direction are passed through the loop of the needle thread forming the upstream chain seam.
To achieve the first object, a seam according to a fourth aspect of the present application is a seam formed by alternately forming chain seams and lock seams by two needles juxtaposed in a substantially perpendicular direction to a sewing direction. The seam includes a first seam and a second seam. A loop of the needle thread forming the chain seam of the first seam is passed through a loop of the needle thread forming the opposed lock seam of the second seam, a stitch is tightened, a loop of the needle thread forming the chain seam of the second seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam of the first seam. A loop of the needle thread forming the chain seam of the second seam is passed through a loop of the needle thread forming the opposed lock seam of the first seam, a stitch is tightened, and a loop of the needle thread forming the chain seam of the first seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam of the second seam.
To achieve the second object, a seam forming device according to a fifth aspect of the present application includes: two needles which are juxtaposed in a substantially perpendicular direction to a sewing direction and to which needle threads for forming chain seams and lock seams are fed; an upper drive means for reciprocating the two needles in a vertical direction; a first looper for passing a loop of the needle thread of one of the needles formed on a back face side of a sewing material through a loop of the needle thread of the other needle in synchronization with vertical movements of the two needles; a loop spreader for retaining the loop of the needle thread of the one needle formed by the first looper until the needle thread of the one needle of the next or later stitch is positioned in the loop of the needle thread of the one needle of the earlier stitch; a second looper for passing the loop of the needle thread of the one needle of the next or later stitch through the loop of the one needle thread retained by the loop spreader; and a lower drive means for causing the first and second loopers and the loop spreader to operate in synchronization with the vertical movements of the two needles. The device forms a seam formed by tightening the chain seam by the lock seam.
To achieve the third object, a seam forming method according to a sixth aspect of the present application is a seam forming method for sewing by forming chain seams and lock seams with needle threads of two needles juxtaposed in a substantially perpendicular direction to a sewing direction. The method includes: a first step of moving down the two needles by a drive means to protrude the needle thread of one needle and the needle thread of the other needle to a back face side of a sewing material; a second step of moving up the two needles by the drive means to form a loop of the needle thread of the one needle and a loop of the needle thread of the other needle on the back face side of the sewing material and passing the loop of the needle thread of the one needle formed on the back face side of the sewing material through the loop of the needle thread of the other needle by a first looper protruding in synchronization with the upward movements of the two needles; a third step of retaining the loop of the needle thread of the one needle, which is retained by the first looper during the upward movements of the two needles, on a loop spreader protruding in synchronization with the upward movements of the two needles and then for returning the first looper to an original position to separate the first looper from the one needle thread; and a fourth step of spreading the loop of the one needle thread, which is retained on the loop spreader, by a second looper protruding in synchronization with the first looper, passing the one needle out of the two lowering needles through the spread loop of the one needle thread, and returning the second looper and the loop spreader to original positions to separate the second looper and the loop spreader from the one needle thread.
The seam according to the invention of the present application is formed by forming the chain seams and the lock seams by the two needles juxtaposed in the substantially perpendicular direction to the sewing direction. Therefore, unlike the conventional seam, the seam can be formed without the trouble of setting the positional relationship between the needle for forming the chain seams and the needle for forming the lock seams in consideration of a feeding pitch width of the needle for forming the chain seams and an interval between the needle for forming the chain seams and the needle for forming the lock seams.
In the seam according to the invention of the present application, the chain seams and the lock seams are not disposed on the same straight line as in the conventional seam but disposed with the predetermined interval therebetween and the loop of the needle thread forming the lock seam pulls and tightens the loop of the needle thread forming the chain seam to the front face side (upward) of the sewing material after pulling the loop aside (toward the lock seam). Therefore, the tightening force and the resisting force are increased, the slackening and raveling are prevented drastically, and tightening of the stitch is performed reliably.
According to seam forming device and forming method according to the invention of the present application, it is possible to efficiently and easily form the seam having the above effects.
a) to 2(d) are perspective views showing a forming process of the seam in
a) to 3(g) are explanatory views showing forming steps of the seam in
a) to 4(c) are explanatory views showing amounted state of the seam in
a) to 6(d) are perspective views showing a forming process of the seam in
a) and 7(b) are explanatory views showing a mounted state of the seam in
a) to 9(d) are perspective views showing a forming process of the seam in
a) and 10(b) are explanatory views showing a mounted state of the seam in
a) to 12(d) are perspective views showing a forming process of the seam in
a) and 13(b) are explanatory views showing a mounted state of the seam in
a) and 14(b) are explanatory views of a conventional seam.
A first embodiment of a seam according to the invention of the present application will be described based on
As shown in
As shown in
The seam 1 is formed by forming the chain seam 10 by the one needle thread 12 and forming the lock seam 20 by the other needle thread 22 simultaneously and tightening, with a tightening portion 25 of the lock seam 20, the portion of the chain seam 10 on the downstream side of the knot portion 15 in the sewing direction shown by an arrow T in
Moreover, the seam 1 includes two threads for pressing and joining the cloths on each of the front face and the back face of the cloths. Therefore, it is possible to overcome weakness after sewing, which is a drawback of the chain seam 10, while maintaining a stretch property due to the chain seam 10 and it is possible to obtain a sewn state of high quality such as soft texture. Moreover, because the seam 1 is formed by using the two needle threads 12 and 22, the respective needle threads 12 and 22 can be fed from spools (not shown) around which large quantities of thread are wound and it is possible to efficiently carry out sewing operation for a long time. Furthermore, the seam 1 has separate thread paths for the two needle threads 12 and 22 and therefore it is possible to reliably prevent stitch skipping to maintain high sewing quality.
As shown in
The two needles 11 and 21 are attached to needle bars by needle clamps, the needle bars being allowed to reciprocate with a predetermined vertical stroke by a known upper drive means (not shown) called a needle bar drive mechanism or the like operating in synchronization with an upper shaft driven for rotation by a sewing machine motor as a drive source. Therefore, the two needles 11 and 21 are caused to reciprocate in a vertical direction by the upper drive means. The upper drive means will not be described in detail.
As shown in
The one needle 11 positioned on the left side of the sewing direction shown by the arrow T in
The seam forming device 30 operates as follows to form the seam 1. If the seam forming device 30 is turned on and switched on (not shown), the upper drive means and the lower drive means interlocked with the upper drive means are actuated, the two needles 11 and 21 perform the vertical reciprocation, and the first looper 31, the loop spreader 32, and the second looper 33 perform predetermined movements.
As shown in
As shown in
As shown in
As shown in
In the seam 1, the chain seams 10 and the lock seams 20 are not disposed on the same straight line but disposed substantially parallel with a predetermined interval therebetween. The loop 13 of the needle thread 12 forming the chain seam 10 is passed through the loop 23 of the needle thread 22 forming the lock seam 20 to form the tightening portion 25 and the loop 13 of the needle thread 12 forming the chain seam 10 is pulled toward the lock seam 20 side and tightened by the tightening portion 25. Therefore, the tightening force is increased and the slackening and raveling are prevented drastically.
A second embodiment of the seam according to the invention of the present application will be described based on
The seam 41 is formed by two needles 11 and 21 juxtaposed in a substantially perpendicular direction to a sewing direction T similarly to the seam 1. As shown in
As shown in
A third embodiment of the seam according to the invention of the present application will be described based on
The seam 61 is formed by two needles 11 and 21 juxtaposed in a substantially perpendicular direction to a sewing direction T. As shown in
As shown in
A fourth embodiment of the seam according to the invention of the present application will be described based on
The seam 81 is formed by two needles 11 and 21 juxtaposed in a substantially perpendicular direction to a sewing direction T. As shown in
As shown in
As described above, the seam 1 is formed by the two needles 11 and 21 juxtaposed in the substantially perpendicular direction to the sewing direction T and includes the chain seams 10 and the lock seams 20 formed by the needle threads 12 and 22 respectively passed through the two needles 11 and 21. The loop 13 of the needle thread 12 forming the chain seam 10 is passed through the loop 23 of the needle thread 22 forming the lock seam 20, the stitch is tightened, and the loop 13 of the needle thread 12 forming the chain seam 10 located on the downstream side in the sewing direction T is passed through the upstream loop 13.
In the seam 41, the chain seams 45 and 47 and the lock seams 46 and 48 are formed alternately by the two needles 11 and 21 juxtaposed in the substantially perpendicular direction to the sewing direction T. The seam 41 consists of the first seam 42 and the second seam 43. The loop 51 of the needle thread 12 forming the chain seam 45 of the first seam 42 is passed through the opposed loop 53 of the needle thread 22 forming the opposed lock seam 48 of the second seam 43, the stitch is tightened, and the loop 52 of the needle thread 12 forming the chain seam 47 of the second seam 43 located on the downstream side in the sewing direction T is passed through the loop 51. The loop 52 of the needle thread 22 forming the chain seam 47 of the second seam 43 is passed through the loop 54 of the needle thread 12 forming the opposed lock seam 46 of the first seam 42, the stitch is tightened, and the loop 51 of the needle thread 12 forming the chain seam 45 of the first seam 42 located on the downstream side in the sewing direction T is passed through the loop 52.
The seam 61 is formed by the two needles 11 and 21 juxtaposed in the substantially perpendicular direction to the sewing direction T and includes the chain seams 65 and the lock seams 70 formed by the needle threads 12 and 22 respectively passed through the two needles 11 and 21. The loop 68 of the needle thread 12 forming the chain seam 65 is passed through the loop 71 of the needle thread 22 forming the lock seam 70, the stitch is tightened, and the loop 68 of the needle thread 12 forming the chain seam 65 and the loop 71 of the needle thread 22 forming the lock seam 70 located on the downstream side in the sewing direction is passed through the upstream loop 68.
The seam 81 is formed by the two needles 11 and 21 juxtaposed in the substantially perpendicular direction to the sewing direction T and includes the chain seams 85 and the lock seams 90 formed by the needle threads 12 and 22 respectively passed through the two needles 11 and 21. The loop 88 of the needle thread 12 forming the chain seam 85 is passed through the loop 91 of the needle thread 22 forming the lock seam 90, the stitch is tightened, and the loop 91 of the needle thread 22 forming the lock seam 90 located on the downstream side in the sewing direction T is passed through the upstream loop 88.
Each of the seams 1, 41, 61, and 81 are formed by forming the chain seams and the lock seams by the two needles 11 and 21 juxtaposed in the substantially perpendicular direction to the sewing direction T. Therefore, unlike the conventional seam, each of the seams can be formed without the trouble of setting the positional relationship between the needle for forming the chain seams and the needle for forming the lock seams in consideration of the feeding pitch width of the needle for forming the chain seams and the interval between the needle for forming the chain seams and the needle for forming the lock seams.
In each of the seams 1, 41, 61, and 81, the chain seams and the lock seams are disposed with the predetermined interval therebetween and the loop of the needle thread forming the lock seam does not immediately pull the loop of the needle thread forming the chain seam to the front face side (upward) of the sewing material but pulls and tightens the loop to the front face side (upward) of the sewing material after pulling the loop aside (toward the lock seam) along the back face side of the sewing material. Therefore, the tightening force and the resisting force are increased, so that the slackening and raveling can be prevented drastically, thereby reliably performing tightening of the stitch.
Industrial Applicability
The seam according to the invention of the present application can be utilized for fabric goods such as clothes and leather goods such as bags.
Number | Date | Country | Kind |
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2007-296142 | Nov 2007 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2008/070227 | 11/6/2008 | WO | 00 | 4/19/2010 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2009/063795 | 5/22/2009 | WO | A |
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5383414 | Winter et al. | Jan 1995 | A |
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46-014222 | Apr 1971 | JP |
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51-066057 | Jun 1976 | JP |
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Entry |
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International Search Report (PCT/ISA/210) for PCT/JP2008/070227 dated Dec. 2, 2008. |
Number | Date | Country | |
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20100212070 A1 | Aug 2010 | US |