JP2003111991A - Bobbin case holder device for lock stitch twin needle sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bobbin case holder device for lock stitch twin needle sewing machine wherein sewing failure due to nonuniform twist of left and right sewing threads is prevented and both left and right stitches are formed as perfect stitches. SOLUTION: The bobbin case holder device comprises two needles 11 and 12 placed left and right; and a pair of left and right bobbin case holders 13 and 14 which are placed in correspondence with the respective needles and have points 13a and 14a for catching needle thread loops formed at the respective needles. The needle 12 positioned on the right side is placed with the gouged portion 12a thereof facing to the right. The bobbin case holder 14 positioned on the right side is rotated clockwise R1 and catches the right thread loop of the needle positioned on the right side. In the bobbin case holder device for lock stitch twin needle sewing machine, the needle 11 positioned on the left side is placed with the gouged portion 11a thereof facing to the right. The bobbin case holder 13 positioned on the left side is rotated counterclockwise R2 and further catches the right thread loop of the needle positioned on the left side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hook device for a lockstitch two-needle sewing machine.

[0002]

2. Description of the Related Art A conventional example of a hook device for a lockstitch two-needle sewing machine will be described with reference to FIGS. In the present specification, “left and right” or “right side” and “left side” refer to the left and right, or the right side and the left side when the operator sees the sewing machine. Further, the “clockwise direction” or the “counterclockwise direction” similarly refers to the clockwise direction or the counterclockwise direction as seen by the operator.

The hook device of a two-needle sewing machine has two hooks 1 and 2 arranged on the left and right and a hook point 3a for catching a needle thread loop formed corresponding to each needle and formed on each needle. , And a pair of left and right shuttles 3 and 4 having a and 4a.

The example shown in FIG. 5 is a general conventional example.
The needle (left needle) 1 arranged on the left side is arranged with the awl portion 1a facing the left side, and the needle (right needle) 2 arranged on the right side is arranged with the awl portion 2a facing the right side. Further, the left and right hooks 3 and 4 are all rotated clockwise R1, and the hook (left hook) 3 arranged on the left side catches the thread loop on the left side of the left needle 1 and the hook (right hook) arranged on the right side. The hook 4 catches the thread loop on the right side of the right needle 2.

In the case of such a relative positional relationship between the needles 1 and 2 and the shuttles 3 and 4, the threading of the sewing threads 5 and 6 is symmetrical with respect to the left and right needles 1 and 2 as shown in (b). , (C), the cloth is fed upward in FIG. 5 and the left and right seams 7, 8 are
To form the sewing thread 5, 6
The rubbing direction is reversed with the left and right needles 1 and 2. Therefore, the Z-twist sewing threads 5 and 6 that are generally used in the sewing machine are twisted from the needle hole to the thread winding side (above (b)) in the right needle 2, and the twist is returned to the cloth side. A seam is formed in the reverse direction, and the left needle 1 is the reverse of this, and the twist movement proceeds from the needle hole in the direction of the seam, and the seam is formed in a state where the number of twists is large. For this reason, the left and right seams become nonuniform, and the problem particularly concentrates on the left needle 1, which causes thread breakage and disorder of stitches (warping, stitch skipping, etc.).

The example shown in FIG. 6 is proposed in Japanese Patent Publication No. 2-15240 to solve this problem, and the configuration and arrangement of the right needle 2 and the right shuttle 4 are shown in FIG. It is the same as the one described above, and the rotation directions of both hooks 3 and 4 are also the same in the clockwise direction R1, but the left needle 1 is arranged so that the counterbore part 1a faces right, and the left hook 3 is the right side of the left needle 1. It has a structure that captures the yarn loop of the. Incidentally, a structure in which the loop to be captured is located on the side away from the center 3c of the hook with respect to the needle 1 such as the left hook 3 is referred to as a removal scooping hook.

According to the hook device of the lockstitch two-needle sewing machine, as shown in (b), the threading of the left needle 1 is from the left side of the needle 1 to the right side, and the threading of the right needle 2 is also from the right side of the needle 2. Since it is performed to the left side, it is not symmetrical as in the case of FIG. 5, (c)
When forming the left and right stitches 7 and 8 as shown in FIG. 3, the sewing threads 5 and 6 are squeezed in the needle holes of the needles 1 and 2 in the same direction. Therefore, even if the Z-twisted sewing threads 5 and 6 are used, the left and right seams 7 and 8 are uniform.

The example shown in FIG. 7 is disclosed in Japanese Patent Laid-Open No. 8-332.
It is proposed in Japanese Patent No. 292, and compared with the one shown in FIG. 5, only the rotation direction of the left hook 3 is different, and the others are the same. That is, as for the left needle 1 and the left hook 3, the left needle 1 is arranged with the burring portion 1a facing left, the left hook 3 rotates in the counterclockwise direction R2, and at the same time, catches the thread loop on the left side of the left needle 1. .

[0009]

However, in the case of the conventional example shown in FIG. 6, the right seam 8 is formed as a perfect stitch as shown in FIG. 8, while the left seam 7 is formed as a hitch stitch. Will be formed. Therefore, the left and right seams 7 and 8 have different tightening and puckering. Similarly, in the case of the conventional example shown in FIG. 7, the right seam 8 is formed as a perfect stitch, while the left seam 7 is formed as a hitch stitch.

Further, in the case of the conventional example shown in FIG. 7, the threading of the left and right needles 1 and 2 is the same as in the conventional example of FIG. 5 as shown in FIG. ), When forming the left and right stitches 7, 8, the direction in which the sewing threads 5, 6 are squeezed into the needle holes of the needles 1, 2 is
At 2, it goes in the opposite direction. Therefore, the problem of poor sewing caused by uneven twisting of the left and right sewing threads when the Z-twisting sewing threads 5 and 6 are used cannot be solved.

Therefore, it is an object of the present invention to prevent a sewing failure caused by uneven twisting of the left and right sewing threads and to form the left and right stitches as a perfect stitch even if a Z-based thread is used. It is to provide a hook device for a simple lockstitch two-needle sewing machine.

[0012]

In order to achieve the above object, according to the present invention, two needles arranged on the left and right and a needle thread formed corresponding to each needle and formed on each needle It has a pair of left and right hooks with hook tips for catching loops, the needle arranged on the right side is arranged with the burring part facing the right side, and the hook arranged on the right side is rotated clockwise and is moved to the right side. In a hook device of a lockstitch two-needle sewing machine that captures the thread loop on the right side of the arranged needle, the needle arranged on the left side is arranged so that the burring portion faces the right side, and the hook arranged on the left side is arranged. A lockstitch 2 characterized by rotating counterclockwise and capturing a thread loop on the right side of a needle arranged on the left side
A shuttle device for the needle sewing machine is provided.

Comparing the structure according to the present invention with the structure shown in FIG. 6 (proposed in Japanese Patent Publication No. 2-15240), only the structure of the shuttle arranged on the left side is different and the structure on the left side is different. The configuration of the needle and the configuration of the shuttle and the needle arranged on the right side are the same. Further, as compared with the configuration shown in FIG. 7 (proposed in Japanese Patent Laid-Open No. 8-332292), the configurations of the shuttle and the needle arranged on the left side are different, and those of the shuttle and the needle arranged on the right side are different. The configuration is the same.
It is preferable to form a notch as a relief groove for the needle at the blade point of the shuttle arranged on the left side.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hook device for a lockstitch two-needle sewing machine according to the present invention will be described below with reference to FIGS.

This shuttle device has two needles 1 arranged on the left and right.
1, 12 and a pair of left and right hooks 1 arranged corresponding to each needle
3 and 14 are provided. As described above, “left / right”, “right side”, “left side”, and “clockwise” “counterclockwise” refer to left / right, right side, left side, clockwise direction, and counterclockwise direction when viewed from the operator. The left and right and clockwise R1 and the counterclockwise R2 in each figure correspond to this.

The needles 11 and 12 are fixed to a needle bar 10 which moves up and down in conjunction with a sewing machine main shaft (not shown). Left needle (left needle) 11 and right needle (right needle)
12 is arranged so that the hollow portions 11a and 12a face the right side. The shuttle (right shuttle) 14 arranged on the right side is rotated in the clockwise direction R1 and the thread loop on the right side of the right needle 12 is captured by the sword tip 14a.

On the other hand, the shuttle (left shuttle) 13 arranged on the left side is rotated in the counterclockwise direction R2, and the sword tip 13a catches the thread loop on the right side of the left needle 11. That is, the left hook 13 is a hook (outer rake hook) of the type in which the loop to be caught is located on the side away from the center 13c of the hook with respect to the needle 11.

At the upper end of the base of the blade 13a of the left hook 13,
A notch 13b that opens upward is formed. When the left needle 11 is raised, the left needle 11 is cut out (escape groove) 1
Pass 3b and rise. That is, the notch 13b is a groove for preventing the left needle 11 from colliding with the base of the sword tip 13a when the needle 11 moves up and allowing passage of the needle.

According to the shuttle device of the present embodiment, FIG.
As shown in, threading the left needle 1 from the left side to the right side of the needle 1,
Since the threading of the right needle 2 is also performed from the left side to the right side of the needle 2, it is not symmetrical as in the case of the conventional example shown in FIG. Therefore, when the left and right stitches 17 and 18 are formed as shown in FIG. 1C, the direction in which the sewing threads 15 and 16 are squeezed into the needle holes of the needles 11 and 12 is the left and right needles 1 and 2.
In the same direction. Therefore, the left and right seams 17, 18 are uniform even when the Z-twisted sewing threads 15, 16 are used.

Further, as shown in FIG. 4, the left and right seams 17, 18 formed according to this embodiment are both formed as perfect stitches. Therefore, there is no difference in tightening or puckering between the left and right seams as in the case of the conventional example shown in FIGS. 6 and 7.

Although the present invention has been described based on the embodiment shown in the drawings, the present invention is not limited to this embodiment and can be variously modified. For example, in the above-described embodiment, the cutout portion is provided at the hook blade tip, but it is also conceivable that a sufficient gap is formed between the hook body and the blade tip to prevent the needle from colliding with the hook blade tip.

[0022]

According to the present invention, the two left and right
A needle and a pair of left and right hooks arranged corresponding to each needle and having hook hook tips for catching needle thread loops formed on each needle. , The hook arranged on the right side is rotated clockwise, and in the hook device of the lockstitch two-needle sewing machine which catches the thread loop on the right side of the needle arranged on the right side, the hook is arranged on the left side. Since the needle is arranged so that the burrow portion faces the right side, the hook arranged on the left side is rotated counterclockwise, and the thread loop on the right side of the needle arranged on the left side is caught, the Z twist Even when the left and right needles are used for the left and right needles, it is possible to prevent a sewing failure caused by uneven twisting of the left and right sewing threads and to form the left and right stitches as a perfect stitch.

When the needle escape groove is formed in the blade tip of the shuttle arranged on the left side, it is possible to prevent the left needle from colliding with the blade tip of the shuttle arranged on the left side when rising.

[Brief description of drawings]

FIG. 1 is a simplified diagram for explaining an embodiment of a hook device of a lockstitch two-needle sewing machine according to the present invention, (a) is a plan view,
(B) is a front view of the needle and (c) is a plan view of the needle and the seam.

FIG. 2 is a perspective view of the present embodiment.

FIG. 3 is a plan view of the present embodiment.

FIG. 4 is a perspective view showing a seam formed according to the present embodiment.

5A and 5B are simplified diagrams for explaining a hook device of a lockstitch two-needle sewing machine according to a conventional example. FIG. 5A is a plan view, FIG. 5B is a front view of the needle, and FIG. 5C is a plan view of the needle and the seam. Is.

6A and 6B are simplified views for explaining a hook device of a lockstitch two-needle sewing machine according to another conventional example. FIG. 6A is a plan view, FIG. 6B is a front view of the needle, and FIG. It is a top view.

FIG. 7 is a schematic view for explaining a hook device of a lockstitch two-needle sewing machine according to still another conventional example, in which (a) is a plan view,
(B) is a front view of the needle and (c) is a plan view of the needle and the seam.

8 is a perspective view for explaining a seam formed by the shuttle device of the conventional example shown in FIGS. 6 and 7. FIG.

[Explanation of symbols]

R1 clockwise R2 counterclockwise 11 left needle 11a, 12a Egg part 12 right needle 13 left pot 13a Kettle point 13b escape groove 14 right pot 14a Kettle point

Continued front page    (72) Inventor Tadashi Yokoyama             1 J, 8-2 Kokuryo-cho, Chofu-shi, Tokyo             Within TUKI CORPORATION (72) Inventor Tatsuhito Akiyama             1 J, 8-2 Kokuryo-cho, Chofu-shi, Tokyo             Within TUKI CORPORATION F term (reference) 3B150 AA03 AA11 CB03 CB27 CD04                       CE01 CE27 DC03 DG03 DG04                       DG17 QA01

Claims (2)

[Claims] 1. A pair of left and right hooks having two needles arranged on the left and right and a hook sword tip which is arranged corresponding to each needle and catches a needle thread loop formed on each needle, The needle arranged on the right side is arranged with the burring part facing to the right side, and the hook arranged on the right side is rotated clockwise and the two lockstitch needles that catch the thread loop on the right side of the needle arranged on the right side. In the hook device of the sewing machine, the needle arranged on the left side is arranged so that the burring portion faces the right side, and the hook arranged on the left side is rotated counterclockwise and the thread on the right side of the needle arranged on the left side is rotated. A hook device for a lockstitch two-needle sewing machine characterized by catching a loop. 2. A hook device for a lockstitch two-needle sewing machine according to claim 1, wherein a hook portion of the hook arranged on the left side is formed with a notch portion for allowing the needle to pass therethrough. A hook device for a 2-needle sewing machine.