JPS6158684A - Yarn holder of hole stitch sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thread holding device for a hole sewing machine, and particularly to a thread holding device for a sewing machine that holds a bobbin thread after automatic thread trimming.

[Conventional technology]

FIG. 2 is a perspective view showing a conventional thread holding device. In the figure, 1 is a moving knife, 2 is a hook part formed on the moving knife 1, 6 is a blade part on the moving knife 1, and 4 is a fixed knife. , 5 is a holding spring, 6 is a guide plate, 7 is a throat plate, 8 is a louver base lace, 9 is a lower thread, 10 is a core thread, and 11 is the entire stitch formation.

The conventional thread holding device is constructed as described above, and after a series of sewing operations are completed and the upper thread is cut, the bobbin thread 9 and core thread 10 coming out of the throat plate 7 are hooked by the action of the moving knife 1. 2 and is cut when the fixed knife 4 and the blade 6 of the movable knife part engage.

During the cutting process, the bobbin thread 9 and the core thread 10 are held by a holding spring 5 which is installed so as to sandwich the movable knife 1 between the movable knife 1 and the stationary knife 4.

After the thread cutting is completed, the throat plate 7 is attached and the louver base race 8 is rotated 180 degrees, and the series of cycles is completed.

[Problem that the invention seeks to solve]

In the conventional thread holding device as described above, both the bobbin thread 9 and the core thread 10 are held after the thread is cut.

However, since the bobbin thread 9 is thinner than the core thread 10, the holding force of the bobbin thread is extremely small compared to that of the core thread, and the thread may be detached from the retaining spring 5. In addition, since the holding spring 5 is attached to a sliding plate (on which the sewing material is placed and moves in a predetermined pattern), the held thread does not come off during sewing, and when the movable knife 1 is operated next, it will not move forward. The held thread will come off. For this reason, in addition to the threads to be cut, the previously held threads are also cut, resulting in a problem that the thread cutting performance is also adversely affected.

This invention was made in order to solve this problem, and it prevents the held thread from coming off when returning to the origin,
To provide a thread holding device for a sewing machine which can automatically pull out the thread held during sewing from a holding plate, prevent skipped stitches at the start of sewing, and stabilize thread tightening.

[Means for solving problems]

In the thread holding device according to the present invention, a thread holding mechanism in which a guide portion is formed in the thread insertion port of the thread holding surface is attached to the side of the throat plate so that the thread holding surface is at the height of the thread path when cutting the thread. A thread handling stepped portion is formed on the upper surface of the throat plate to separate the bobbin thread and the core thread.

[Effect]

In this invention, when the bobbin thread and the core thread are hooked on the movable knife, they are divided into upper and lower parts by the tension difference and the thread handling step part, and only the bobbin thread is held on the thread holding surface via the guide part. .

〔Example〕

FIG. 1 is a perspective view showing one embodiment of the present invention.
11 is exactly the same as the conventional device described above. 12it
, a holding spring 16 is a thread holding plate attached to the side of the throat plate 7 so as to hold the bobbin thread 9 between it and the holding spring 12, and the holding spring 12 forms a thread holding mechanism f:llll. ing.

Reference numeral 14 indicates a thread, a guide portion formed at the thread insertion opening on the thread holding surface of the holding mechanism, and reference numeral 16 a thread handling step portion (hereinafter abbreviated as step portion) formed on the upper surface 15 of the throat plate 7.

In the thread holding device configured as described above.

After a series of sewing operations are completed and the upper thread is cut, the lower thread 9 and core thread 10 coming out of the throat plate 7 are included in the movable knife 1 and hooked onto the hook 2. At this time, the tension of the core thread 10Fi is small, and the core thread 10Fi crosses over the stepped portion 16 on the throat plate 7. Since the upper surface of the stepped portion 16 is higher than the upper surface of the holding spring 12, the core yarn 10Fi.

Not retained.

On the other hand, since the bobbin thread 9 has a large tension, the needle plate 7
Unable to get over the stepped portion 16 on the thread holding plate 16, the upper surface 15 of the needle plate 7 is
4, the thread holding spring 12 is held between the thread holding plate 160 and the thread holding plate 160.

Also, after thread cutting, the looper base race 8 rotates 180°,
Even when returning to the origin, the held bobbin thread 9 does not come off.

〔Effect of the invention〕

As described above, according to the present invention, the bobbin thread holding mechanism is attached to the side of the throat plate so that its thread holding surface is located at the thread path height of the bobbin thread during thread trimming, and the upper surface of the needle plate Since the thread handling step part is formed to separate the bobbin thread and the core thread, it becomes possible to hold only the bobbin thread that needs to be held. As a result, the held thread is prevented from coming out when returning to the origin, and the thread held in the middle of sewing can automatically come out through the thread holding plate, preventing skipped stitches at the beginning of sewing and stabilizing the thread tightening. It has the effect of measuring

[Brief explanation of drawings]

FIG. 1 is a perspective view of a thread holding device of a hole sewing machine according to an embodiment of the present invention, and FIG. 2 is a perspective view of a thread holding device of a conventional hole sewing machine. 7... Throat plate, 9... Lower thread, 10... Core thread, 12.
...Retaining spring, 16... Retaining plate, 14... Guide part, 16... Step part. In addition, in the figures, the same reference numerals indicate the same or corresponding parts. Patent applicant Mitsubishi Electric Corporation 13: Sawa special plate 14: Kaid part 16: Step part

Claims (1)

[Claims] A thread holding mechanism is provided on the side of the needle plate so that a guide part is formed at the thread insertion opening of the thread holding surface and the thread holding surface is at the height of the thread path during thread trimming, and a thread holding mechanism is provided on the top surface of the needle plate. A thread holding device for a hole sewing machine, comprising a thread handling step portion that separates a formed bobbin thread and a core thread.