JP3576022B2 - Multi needle double chain stitch machine - Google Patents

Description

【００２２】
【発明の効果】
以上のように、本発明によれば、下死点からの針の上昇時に、針からルーパの腹部を経て生地に伸びるループ状の針糸によって、生地からルーパの目孔に連なるルーパ糸がルーパに沿うことがなくなるので、確実に前記糸三角形を形成して二重環縫い目を形成できるという効果を奏する。また、下死点からの針の上昇時に、針に形成される針糸ループに捩れが生じないので、針糸ループをルーパで確実にすくうことができる。
【００２３】
請求項２によれば、前記糸三角形における各針糸への係合解除が右側のループ状針糸から行われるので、前記糸三角形の形成をより確実に行うことができる。
【００２４】
請求項３によれば、縫目中における右針糸の比率が多くなるので、全体的に伸びのある二重環縫い目を形成できる。
【図面の簡単な説明】
【図１】本発明に適用される多本針二重環縫いミシンの外観斜視図である。
【図２】同上ミシンの要部説明図である。
【図３】同上ミシンの要部説明図である。
【図４】同上ミシンの要部説明図である。
【図５】同上ミシンの要部説明図である。
【図６】同上ミシンの要部説明図である。
【図７】同上ミシンの要部説明図である。
【図８】同上ミシンの各針糸の糸捌き量を説明する図である。
【図９】従来の２本針二重環縫いミシンによって形成されるシームの構成図である。
【図１０】従来の多本針二重環縫いミシンの外観斜視図である。
【図１１】従来の多本針二重環縫いミシンの各針糸の糸捌き量を説明する図である。
【符号の説明】
１，２ 左右の針（複数本の針）
１ａ 針棒
３ ルーパ
３ｅ ルーパ目孔
４ 左針用の針糸
４Ｌ ループ状針糸
５ 右針用の針糸
５Ｌ ループ状針糸
６ ルーパ糸
７ 糸調子器（複数の糸調子器）
１４，１４ 一対の針棒糸道（一対の糸案内）
１４ａ，１４ｂ 糸道孔（糸通し孔）
１５ 糸捌き
１５ａ 第１カム
Ｍ 主軸（ミシン主軸）
Ｓ 二重環縫い目[0001]
[Industrial applications]
The present invention relates to a multi-needle double chain stitch sewing machine, and more particularly to a two-needle or three-needle double chain stitch sewing machine capable of forming a good double chain stitch on a thin, stiff fabric.
[0002]
[Prior art]
A conventional multi-needle double chain stitch sewing machine having two needles 1 and 2 as shown in FIG. 10 is arranged side by side, and the lower end of the right needle 2 is higher than the lower end of the left needle 1. There are provided two needles 1 and 2 fixed to the lower end of the rod, and a looper 3 which advances and retreats from the right side toward each needle. As shown in FIG. 9, the double chain stitch S extends from the left needle thread 4 </ b> L and the needle thread 5 </ b> L and the cloth (not shown), which are looped by the looper 3, along the looper 3 through the looper eye hole 3 e. The left needle 1 and the right needle 2 respectively descend in the thread triangle formed by the looper thread 6, rise through the bottom dead center, and the looper 3 retreats and advances through the right dead center to form new needles formed on each needle. It is configured to scoop the yarn loop.
[0003]
In order to form the double chain stitch S on the fabric with the double chain stitch machine having the above-described configuration, a needle thread control mechanism has conventionally been provided between the needle thread paths between the needles 1, 2 and the thread tensioner groups 7a, 7b, 7c. 8 are arranged (FIG. 10). The needle thread control mechanism 8 includes a needle thread path 9 fixed to the upper end of the needle bar 1a, a needle thread path holder 10 fixed to the sewing machine arm A, and one end fixed to the swing shaft 11 and the other end. A needle thread handling key 12 having through holes 12a and 12b at its free end and swinging about a swing shaft 11 is provided. The needle bar thread path 9 extends from the upper end of the needle bar 1a in a direction opposite to the cloth feeding direction F of the sewing machine, and has a plurality of thread path holes 9a and 9b at its tip. The needle bar thread path 9 moves up and down in conjunction with the up and down movement of the needle bar 1a. The needle thread path holder 10 has a plurality of needle thread paths 10a and 10b for individually guiding the left and right needle threads 4 and 5, respectively. The right needle thread path 10b is fixed higher than the left needle thread path 10a. The vertical position of the needle thread path holder 10 can be adjusted via the elongated hole 10h and the screw 13, so that the vertical position of each of the needle thread paths 10a and 10b can be adjusted collectively. The swing shaft 11 swings in conjunction with the vertical movement of the needle bar 1a. The needle thread handle 12 passes through a plurality of through holes 12a and 12b so as to guide the left and right needle threads 4 and 5 individually. The thread tensioner group 7 is composed of thread tensioners 7a and 7b arranged for the left and right needle threads 4 and 5, and a thread tensioner 7c arranged for the looper thread 6, and applies tension to the corresponding thread. Is what you do.
[0004]
FIG. 11 shows the thread handling amounts of the respective needle threads 4 and 5 controlled between the needle thread paths of the sewing machine needles 1 and 2 and the needle thread paths 10a and 10b in FIG. In the figure, the vertical axis E represents the thread handling amount (mm) of each of the needle threads 4 and 5, and the horizontal axis A represents 360 degrees of an angle corresponding to one rotation of the main shaft M of the sewing machine, that is, one stitch forming process. Represents. The sewing machine spindle M is configured such that when the angle is 0 °, the left and right needles are respectively at the top dead center. When the angle of the sewing machine main axis M is around 90 °, the left needle 1 descends to the thread triangle, and when the angle of the sewing machine main axis M is around 120 °, the right needle 2 descends to the thread triangle. When the angle of the sewing machine spindle M is around 210 °, the looper 3 scoops a new needle thread loop formed on the right needle 2, and when the angle of the sewing machine spindle M is around 240 °, the looper 3 is formed on the left needle 1. Scoop a new needle thread loop. The thread handling amount of the left needle thread 4 increases from about 10 °, reaches a maximum at about 180 ° at the beginning, and becomes zero at about 330 °. The thread handling amount of the right needle thread 5 increases from around 20 °, starts at around 170 ° to around 210 °, and reaches a maximum, and becomes zero at around 340 °. Between the vicinity of the angle 50 ° and the vicinity of 340 ° of the main shaft M of the sewing machine, the thread handling amount of the right needle thread exceeds the thread handling amount of the left needle thread.
[0005]
[Problems to be solved by the invention]
However, in the conventional apparatus as described above, as shown in FIG. 11, the angle of the main shaft of the sewing machine is 240 ° or more, that is, the needle rises through the bottom dead center and the looper advances to scoop the right needle thread loop. There is not enough slack from the point of time to the top dead center, and the amount of loop-shaped right needle thread extending from the needle to the fabric through the abdomen of the looper is reduced. Therefore, the looper thread connected to the eye of the looper from the fabric is made to follow the abdomen of the looper by the loop-shaped right needle thread. As a result, there is a concern that the so-called “return skip” may occur, in which the right needle does not descend into the thread triangle formed by the loop-shaped right needle thread and the looper thread.
[0006]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a multi-needle double chain stitch sewing machine that can solve the above-described problems with a simple configuration and can form double chain stitches reliably.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the apparatus according to claim 1 of the present invention is arranged in such a manner that the lower end of the right needle is higher than the lower end of the left needle and is fixed to the lower end of the needle bar. It has two needles and a looper that advances and retreats toward each needle from the right side, and the needle and the looper cooperate with each other to form a loop-shaped needle thread and cloth through the looper through the looper eye to the looper. In a multi-needle double chain stitch sewing machine that forms a double chain stitch on the fabric after forming a thread triangle with a looper thread along the pair, a pair of thread path holes fixed to the upper end of the needle bar and provided facing each other And a first cam fixed to the sewing machine frame and extending along the direction of rising forward with respect to the fabric feeding direction so as to cross between the yarn path holes and a first cam extending along the vertical direction of the needle bar. and a handling member which forms a second cam, wherein with the descent of the needle bar needle Engage needle thread to the first cam between the pair of thread guide when lowering the yarn triangle, and a second cam to scoop looper moves forward needle thread loop with the needle rises through the bottom dead center Is maintained, and then the engagement with both cams is sequentially released.
[0008]
According to a second aspect of the present invention, the disengagement of the needle thread by the first cam is performed from the needle thread inserted through the rightmost needle.
[0009]
The device according to claim 3, wherein the path length of each needle thread between the thread guides at the time of engagement with the second cam is longer as the needle thread inserted through the right needle. is there.
[0010]
[Action]
According to the first aspect of the present invention, each needle thread between the pair of thread guides is sequentially engaged with the first cam when the needle descends to the thread triangle with the descending of the needle bar. Then, the engagement with the two cams is sequentially released after maintaining the engagement with the second cam until the looper advances with the needle rising through the bottom dead center and scoops the needle thread loop. After the release, each needle thread is rapidly loosened, and the loop-shaped needle thread is hung on the looper so that the looper thread extending from the cloth to the looper eye does not follow the looper.
[0011]
According to the second aspect of the present invention, the disengagement of the triangular thread from each needle thread is performed from the rightmost loop-shaped needle thread.
[0012]
According to the third aspect of the present invention, the ratio of the right needle thread in the stitch increases.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings, but description of parts common to conventional sewing machines will be omitted. FIG. 1 is an overall perspective view of a two-needle double chain stitch sewing machine according to the present invention. A pair of needle bar thread paths 14, 14 (a pair of thread guides) is fixed to the upper end of the needle bar 1a. The pair of needle bar thread paths 14 and 14 extend in a direction opposite to the fabric feeding direction F of the sewing machine, and the tips thereof are bent upward. At the distal ends of the needle bar thread paths 14, 14 bent upward, thread path holes 14a, 14a for left needle thread and thread path holes 14b, 14b for right needle thread are arranged at opposing portions. As shown in FIG. 2, both yarn path holes 14a, 14b is along the direction to be raised before with respect to the cloth feed direction F, it is along the direction intersecting the lifting direction of the needle bar 1a. The thread path holes 14a, 14a for the left needle thread are set lower than the thread path holes 14b, 14b for the right needle thread and on the rear side in the fabric feeding direction F.
[0014]
On the sewing machine arm A which constitutes a part of the sewing machine frame, there is arranged a thread handling 15 which engages with each needle thread between the needle bar thread paths 14 when the needle bar 1a is raised and lowered. The thread separating device 15 forms a first cam 15a extending along a direction that rises forward with respect to the cloth feeding direction F, and a second cam 15b extending along a direction in which the needle bar 1a moves up and down. The first cam 15a is fixed to a bracket 18 by a first slot 16 and a screw 17 so as to cross between the two thread passage holes of the needle bar thread passages 14,14. The bracket 18 is fixed to the sewing machine arm A via the second slot 19 and the screw 20. The second slot 19 of the bracket 18 and the screw 20 allow the thread handler 15 to change its fixed position up and down along the vertical direction of the needle bar 1a. Can be adjusted at the timing of engagement. The first slot 16 of the bracket 18 and the screw 17 allow the thread handling unit 15 to change the fixed position back and forth along the fabric feeding direction F, and adjust the path length of each needle thread 4 and 5 between the thread path holes. it can. The left and right needle thread paths 10a and 10b are set at substantially the same height.
[0015]
The needle thread 4 for the left needle is supplied from a thread supply source, not shown, from a thread tensioner 7a of a thread tensioner group, a needle thread path 10a of a needle thread holder, a through hole 12a of a needle thread handling key, and a thread path hole of a needle bar thread path. The needle thread 5 for the right needle is passed through an eye hole of the left needle 1 through 14a, 14a, and a thread tension source 7b of a thread tensioner, a needle thread path 10b of a needle thread holder, and a needle thread handling device are provided from a thread supply source (not shown). The right needle 2 is passed through the through hole 12b of the key and the thread path holes 14b, 14b of the needle bar thread path.
[0016]
Next, the operation of the two-needle double chain stitch sewing machine of the present invention configured as described above will be described with reference to FIGS.
As shown in FIG. 8, when the angle of the main shaft M of the sewing machine is 0 °, that is, when the needle bar 1a is at the top dead center, each needle thread 4 inserted into each thread hole of the pair of needle bar thread paths 14 , 5 are not engaged with the first cam 15a of the thread handling 15, and are located above (FIG. 2). With the lowering of the needle bar 1a, the thread handling amount of each of the needle threads 4 and 5 starts to rise almost in the same manner from around 20 °. When the angle of the main shaft M of the sewing machine reaches about 90 °, first, the thread formed by the needle thread 4L that is hung on the looper 3 to form a loop and the looper thread 6 from the cloth through the looper eye 3e and along the looper 3. The tip of the left needle 1 reaches the triangle. At this time, as shown in FIG. 3, the left needle thread 4 inserted between the left needle thread path holes 14a, 14a engages with the first cam 15a of the thread handling 15.
[0017]
Subsequently, when the needle bar 1a further descends and the angle of the main shaft M of the sewing machine reaches about 120 °, the needle thread 5L which is hung on the looper 3 and forms a loop from the cloth and the looper along the looper 3 through the looper eye 3e. The right needle 2 reaches between the needle thread 4L and the needle thread 5L, which are formed by the thread 6 and a triangular thread. At this time, the right needle thread 5 inserted between the thread paths 14b for the right needle engages with the first cam 15a of the thread handling 15, as shown in FIG. When the angle of the sewing machine main shaft M reaches about 130 ° due to the further lowering of the needle bar 1a, the thread handling amount of the left needle thread becomes maximum, and when the angle of the sewing machine main shaft M reaches about 170 °, the thread of the right needle thread becomes large. The amount of handling is maximized. The needle threads 4 and 5 between the thread passage holes engaged with the first cam 15a are slid to the second cam 15b at this time, and the engaged state is maintained (FIG. 5). In this engaged state, the path length of the needle thread 5 between the thread path holes 14b, 14b is longer than the path length of the needle thread 4 between the thread path holes 14a, 14a.
[0018]
When the needles 1 and 2 fixed to the lower end of the needle bar 1a rise through the bottom dead center and the angle of the main shaft M of the sewing machine reaches about 210 °, the looper 3 moves forward with the rise of the right needle 2 and the right needle first. The new needle thread loop formed in No. 2 is scooped. Subsequently, when the needle bar 1a moves up and the angle of the main shaft M of the sewing machine reaches about 240 °, the looper 3 moves forward with the rise of the left needle 1 and scoops a new needle thread loop formed on the left needle 1. Between these, the needle threads 4 and 5 between the needle bar thread paths 14 and 14 engaged with the second cam 15b slide to the first cam 15a (FIG. 6). The threading amount of the right needle thread maintains the maximum until the angle of the sewing machine spindle M reaches about 200 °, and then decreases sharply. Maintain the maximum until reaching ゜, then decrease. The needle thread 4 and 5 are engaged with the cam of the thread handling 15 until the needles 1 and 2 rise through the bottom dead center and the looper 3 scoops a new needle thread loop formed on the needles 1 and 2. So that the needle thread loop does not twist. This is effective to ensure that the looper 3 is scooped with the needle thread loop.
[0019]
After the looper 3 scoops the needle thread loop formed on both needles 1 and 2, the needle thread 5 between the thread passage holes 14b and 14b engaged with the first cam 15a is disengaged (FIG. 7). Thereafter, the needle thread 4 between the thread path holes 14a, 14a engaged with the first cam 15a is released. By releasing these engagements, the looper thread 6 continuing from the fabric to the looper eye hole 3e does not follow the abdomen of the looper 3, and as a result, the thread triangle can be formed stably. Further, in a state where each of the needle threads 4 and 5 is engaged with the second cam 15b of the thread handling 15, the path length of the needle thread between the right thread path holes is longer than that for the left needle. After the disengagement state is released, the slack degree of the loop-shaped needle thread on the right side becomes larger than that on the left side. As a result, the ratio of the right needle thread in the seam is increased, and a double-ringed seam that is entirely elongated can be formed. Due to the action of the cams 15a and 15b in the thread handling 15, the thread handling amount of the right needle thread exceeds the thread handling amount of the left needle thread between about 140 ° and 220 ° of the main shaft M of the sewing machine. Are both approximately the same amount of thread handling.
[0020]
Table 1 below shows a comparison of thread amounts when sewing is performed with the conventional sewing machine shown in FIG. 10 and the sewing machine according to the present invention shown in FIG.
[0021]
[Table 1]

[0022]
【The invention's effect】
As described above, according to the present invention, when the needle is lifted from the bottom dead center, the looper thread extending from the fabric to the eye of the looper is formed by the loop-shaped needle thread extending from the needle to the fabric through the abdomen of the looper. Therefore, there is an effect that the thread triangle can be surely formed to form a double ring seam. Further, when the needle is raised from the bottom dead center, the needle thread loop formed on the needle is not twisted, so that the needle thread loop can be reliably scooped by the looper.
[0023]
According to the second aspect, the disengagement of the thread triangle from each needle thread is performed from the right loop needle thread, so that the thread triangle can be formed more reliably.
[0024]
According to the third aspect, since the ratio of the right needle thread in the stitch increases, a double-ring stitch that is entirely elongated can be formed.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a multi-needle double chain stitch sewing machine applied to the present invention.
FIG. 2 is an explanatory view of a main part of the sewing machine.
FIG. 3 is an explanatory view of a main part of the sewing machine.
FIG. 4 is an explanatory view of a main part of the sewing machine.
FIG. 5 is an explanatory view of a main part of the sewing machine.
FIG. 6 is an explanatory view of a main part of the sewing machine.
FIG. 7 is an explanatory diagram of a main part of the sewing machine.
FIG. 8 is a diagram illustrating a thread handling amount of each needle thread of the sewing machine.
FIG. 9 is a configuration diagram of a seam formed by a conventional two-needle double chain stitch sewing machine.
FIG. 10 is an external perspective view of a conventional multi-needle double chain stitch sewing machine.
FIG. 11 is a diagram illustrating a thread release amount of each needle thread of a conventional multi-needle double chain stitch sewing machine.
[Explanation of symbols]
1,2 left and right needles (multiple needles)
1a Needle bar 3 Looper 3e Looper eye hole 4 Needle thread 4L for left needle Loop needle thread 5 Needle thread 5L for right needle Loop needle thread 6 Looper thread 7 Thread tensioner (plural thread tensioners)
14, a pair of needle bar thread paths (a pair of thread guides)
14a, 14b thread path hole (thread passing hole)
15 Thread handling 15a First cam M spindle (sewing machine spindle)
S double chain stitch

Claims (3)

At least two needles which are arranged side by side at the lower end of the needle bar, the lower end of the right needle is higher than the lower end of the left needle, and are fixed to the lower end of the needle bar, and a looper which advances and retreats from the right side toward each needle. The needle and the looper cooperate with each other to form a triangular thread triangle formed by the looped needle thread and the looped needle thread from the fabric through the looper eye hole, and then forming a double ring seam on the fabric. In the multi-needle double chain stitch sewing machine to be formed, a pair of thread guides fixed to the upper end of the needle bar and provided with a plurality of thread path holes facing each other are fixed to the sewing machine frame, and a gap between the thread path holes is provided. A first cam extending along a direction that rises forward with respect to the fabric feeding direction so as to traverse, and a yarn handling formed with a second cam extending along the elevating direction of the needle bar. needle thread is first between a pair of thread guide when said needle drops into the yarn triangle It engages the arm, so as to release the engagement to subsequently both cam to maintain engagement between the second cam until the looper moves forward scoop needle thread loop with the needle rises through the bottom dead center sequentially Multi-needle double chain stitch machine characterized by the following. 2. The multi-needle double chain stitch sewing machine according to claim 1, wherein the disengagement of the needle thread by the first cam is performed from the needle thread inserted through the rightmost needle. 3. The multiple thread according to claim 1, wherein a path length of each needle thread between the thread guides at the time of engagement with the second cam is longer as a needle thread inserted through the right needle. 4. Needle double chain stitch machine.

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