JPH0860522A - Method of repairing yarn break in multi-head type ring sewing machine - Google Patents

Abstract

PURPOSE: To make it unnecessary to bore a hole on the base (substrate) cloth for picking up the broken yarn, when a yarn break occurs, to prevent the threads extending to the hooks from being pulled out excessively long in the other normal machine heads whereby the following manual thread breaking is made unneeded and wrinkles on the substrate cloth can be also prevented. CONSTITUTION: When a thread is broken at the machine head 2A, the threads continuing to the hooks are held above the looper and cut below the needle plate 4 in the other normal machine heads 2B-2D. The substrate cloth W is transferred together with the cloth-holding frame 3 from the embroidering position to the thread-picking up position and the thread-passing hole 6 on the needle plate 4 is exposed. In the machine head 2A of thread breakage, the broken thread is picked up from the thread-passing hole 6 upward above the needle plate 4, then the substrate cloth W is allowed to move together with the cloth-holding frame 3 from the thread-picking up position to the embroidering-restarting position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-head chain stitch sewing machine having at least two sewing machine heads and a method of repairing a thread breakage in a sewing machine head.

[0002]

2. Description of the Related Art In a multi-head chain stitch sewing machine, when thread breakage occurs during an embroidery operation, the broken thread is pulled into the looper by its own weight and thread tension and falls below. In such a case, conventionally, as shown in FIG. 9, in a sewing machine head in which thread breakage has occurred, the thread take-up tool 52 made of wire is pierced into the work cloth W while the work cloth W is left at the sewing position. The looper 51 is penetrated and the thread T is attached to the lower end of the thread take-up tool 52.
And was taken out above the needle plate 53.

[0003]

However, according to the conventional thread breakage repairing method, it is necessary to pierce the work cloth W with the thread take-up tool 52, so that the work cloth W has a hole and the appearance of the sewn product is deteriorated. There was a problem of doing. When the work cloth W has dense embroidery stitches A, the work cloth W is made of a hard material such as leather, or when the work cloth W is sewn with appliqué pieces. However, there is also a problem that it is difficult to pierce the thread take-up tool 52 and it takes a lot of time to repair the thread break.

JP-A-2-104761 discloses that in a single-head embroidery sewing machine having one sewing machine head, when the thread breaks, the work cloth is moved to a thread take-out position away from the sewing position and a hole is formed in the work cloth. A technique for taking out a thread without opening the thread is disclosed. However, in a multi-head chain stitch sewing machine having at least two sewing machine heads, if the work cloth is moved immediately after thread breakage, as shown in FIG. As W moves, the work cloth W is crocheted 54
The thread T that is continuous with the thread T is pulled out for a long time, and it becomes necessary to manually cut the thread T later, or the work cloth W is pulled by the thread T and becomes wrinkled, which hinders the movement itself of the work cloth W. It causes another trouble such as coming.

Therefore, an object of the present invention is, in a multi-head chain stitch sewing machine having at least two sewing machine heads, in the sewing machine head in which thread breakage occurs, it is necessary to make a hole in the work cloth when the thread is taken out upward. Therefore, the thread breakage repair work can be easily performed, the appearance of the sewn product is not deteriorated, and with other normal sewing heads, the thread that is linked to the crochet needle is not pulled out for a long time, so that the thread trimming by the subsequent manual work It is an object of the present invention to provide a thread breakage repairing method for a multi-head chain stitch sewing machine that requires no work and does not cause wrinkles on the work cloth, and allows the work cloth to be moved smoothly.

[0006]

In order to solve the above problems, the thread breakage repairing method of the present invention is provided with at least two sewing machine heads, and each sewing machine head is provided with a multi-head chain stitch provided with a vertically moving crochet needle. In a sewing machine, when thread breakage occurs in one sewing machine head, in another normal sewing machine head, a step of holding the thread connected to the crochet above the looper and cutting it under the needle plate, and in all sewing machine heads The process of moving the work cloth together with the cloth support frame from the sewing position to the thread take-out position to expose the thread passing hole of the needle plate, and in the sewing machine head where the thread breakage occurred, The method is characterized by including a step of taking out above the plate and a step of moving the work cloth together with the cloth support frame from the thread take-out position to the sewing restart position in all the sewing machine heads.

Here, although it is possible to manually move the cloth support frame, it is desirable to automatically move the cloth support frame by utilizing an existing controller of the chain stitch sewing machine. In this case, the sewing position of the cloth support frame is counted by the counter and stored in the memory, and the thread take-out position is input and set in advance at a predetermined position where the thread passing hole of the needle plate is exposed from the work cloth. Then, the movement amount of the cloth support frame is calculated based on the X and Y coordinate values at each position, and the frame drive mechanism is automatically controlled according to the calculation result (see pages 3 to 5 of the above publication). Although the sewing restart position of the cloth support frame may be the same as the sewing position, one or more stitches (1-10
In the case where the needle is operated, the distance corresponding to the number of stitches is before the sewing position.

[0008]

According to the thread breakage repairing method of the present invention, the threading hole of the needle plate is exposed by moving the cloth support frame to the thread take-out position. The thread can be taken out without making a hole. Further, since the thread is held and cut by the normal sewing machine head prior to the movement of the cloth support frame, there is no fear that the work cloth pulls out the thread connected to the crochet for a long time.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show a multi-head chain stitch sewing machine 1
2 schematically shows a plane configuration of the bed, and the bed is not shown here. Above the bed, four sewing machine heads 2A to 2D are arranged side by side, and a cloth support frame 3 common to each sewing machine head 2 is arranged so as to be movable back and forth and left and right. A needle plate 4 is arranged on the upper surface of the bed at a position corresponding to each sewing machine head 2, and the needle plate 4 is provided with a needle hole 5 and a threading hole 6. The cloth support frame 3 has an embroidery frame 7
The work cloth W is supported through the work cloth W, and dense embroidery stitches A are formed on the work cloth W.

Incidentally, FIG. 1 shows a state in which the cloth support frame 3 is arranged at the sewing position so that the sewing point of the work cloth W is aligned with the needle hole 5, and FIG. 2 shows the threading hole 6 from the work cloth W. It shows a state in which the cloth support frame 3 is arranged at the threading position so as to be exposed. The existing controller (not shown) of the chain stitch sewing machine 1 has a counter for counting the sewing position of the cloth support frame 3, an input section for the operator to set the thread take-out position, and X, Y coordinates of each position. A memory that stores values, a calculation unit that calculates the movement amount of the cloth support frame 3 based on those coordinate values, and a control unit that controls the frame drive mechanism according to the calculation result are provided.

3 to 5 show the structure of the sewing device provided for each sewing machine head 2, and the bed 8 is shown by a chain line in FIGS. 4 and 5. A mechanism box 9 is provided below the bed 8 at a position corresponding to the sewing machine head 2, and the needle plate 4 is attached to the upper surface of the mechanism box 9. In the mechanism box 9, the same number of loopers 10 and thread holding members 11 are arranged on a common slider (not shown). The slider is driven by a known color changing mechanism (not shown), and the looper 10 and the thread holding member 11 are selectively indexed to the needle drop point of the crochet needle 12.

The looper 10 includes a needle insertion hole 13 and a yarn feeding hole 14.
And rotatably about a vertical axis, and the needle plate 4
Is provided so as to be able to move up and down between an operating position that approaches the position and a rest position below the operating position. The thread holding member 11 includes a fixed clamp 15 and a movable clamp 16, and is configured to hold the thread T connected to the crochet needle 12 above the looper 10 in the rest position in the closed state thereof. The thread holding member 11 is provided with a spring 17 that biases the movable clamp 16 in the closing direction, and the mechanism box 9 is provided with a solenoid 18 that opens and closes the thread holding member 11 at the needle drop point.

A thread cutting member 20 is provided on a support plate 19 fixed to the mechanism box 9. The thread cutting member 20 is a crochet needle 1.
The yarn T continuous with 2 is cut between the yarn holding member 11 and the needle plate 4. The thread cutting member 20 is a fixed knife 21.
The movable knife 2 is configured to be opened and closed by the movable knife 22 and the movable knife 22.
2, a cam groove 23 is formed. Also, the support plate 19
A thread guide member 24 is rotatably supported by the looper 10 and
The yarn T is hooked between the needle plate 4 and the needle plate 4 and can be inserted into the yarn holding member 11 and the thread cutting member 20. A pair of upper and lower retaining pieces 25 are formed at the tip of the yarn guide member 24, and a cam plate 27 having a cam groove 26 is integrally rotatably coupled to the base end of the yarn guide member 24.

An operating piece 29 is slidably supported in the long groove 28 of the support plate 19, and a pin 30, which is fitted into the movable knife 22 and the cam grooves 23 and 26 of the cam plate 27, is mounted on the operating piece 29.
31 is projected. The operating piece 29 is connected to the rod 33 via the rotating body 32, and as the rod 33 moves,
According to the shapes of the cam grooves 23 and 26, the movable knife 22 of the thread cutting member 20 closes and cuts the thread T immediately after the thread guiding member 24 inserts the thread T into the thread holding member 11 and the thread cutting member 20. It is configured.

In the multi-head chain stitch sewing machine configured as described above, a thread trimming repair method will be described next. When thread breakage occurs in the sewing machine head 2A during the embroidery operation shown in FIG. 1, first, in response to a signal from a thread breakage detector (not shown), the crochet needles 12 and the cloth support frame 3 of all the sewing machine heads 2A to 2D. Is stopped, and as shown in FIG.
The looper 10 is lowered to the rest position. The sewing position of the cloth support frame 3 at this time is stored in the memory (not shown) of the control device.
Memorized in.

Next, as shown in FIG. 6, in the other normal sewing heads 2B to 2D in which thread breakage has not occurred, the solenoid 18 is urged to project and the thread holding member 11 at the needle drop point is opened. . In synchronization with this, the rod 33 is driven in the direction of the arrow, the yarn guide member 24 is rotated according to the shape of the cam groove 26, and the hooking piece 25 thereof causes the looper 10 to rotate.
The thread T between the needle plate 4 and the needle plate 4 is inserted into the thread holding member 11 and the thread cutting member 20.

Next, as shown in FIG. 7, in the sewing machine heads 2B to 2D, the solenoid 18 is deenergized, the thread holding member 11 is closed, and the thread T connected to the crochet needle 12 is fixed and clamped above the looper 10. It is held between 15 and the movable clamp 16. Immediately after this, with the movement of the rod 33, the movable knife 22 of the thread cutting member 20 is closed, and the thread T is cut below the needle plate 4.

Then, in all the sewing heads 2A to 2D, the work cloth W is automatically moved together with the cloth support frame 3 from the sewing position shown in FIG. 1 to the thread take-out position shown in FIG.
The threading hole 6 is exposed. At this time, since the thread T has been cut in advance in the normal sewing machine heads 2B to 2D, the work cloth W may pull out the thread connected to the crochet with the movement of the cloth support frame 3 (the phenomenon of FIG. 10). )
Nor. For this reason, there is no need for subsequent thread cutting work, and there is no concern that wrinkles will occur on the work cloth W.
Can be moved smoothly.

Next, as shown in FIG. 8, in the sewing machine head 2A in which the thread breakage has occurred, the thread T passes through the thread feeding hole 14 of the looper 10 from the thread passing hole 6 to above the needle plate 4 by the thread take-up tool 52. Taken out. In this case, since the threading hole 6 is exposed, the thread T can be easily taken out without making a hole in the work cloth W by the thread take-up tool 52.

After that, the cloth support frame 3 moves from the thread take-out position shown in FIG. 2 to the sewing restart position (that is, a position before the previous sewing position shown in FIG. 1 by the number of stitches due to the inertial operation of the crochet needle 12).
Moved to. Then, when the embroidery operation is restarted, the thread holding members 11 are opened in all the sewing machine heads 2A to 2D, the vertical movement of the first hook 12 and the looper 10 are performed.
The thread T is automatically hooked on the hook portion 12a of the crochet needle 12 with the rotation of the.

[0021]

As described in detail above, according to the thread breakage repairing method of the present invention, in a multi-head chain stitch sewing machine having at least two sewing machine heads, the thread is broken upward in the sewing machine head where thread breakage occurs. There is no need to make holes in the work cloth when taking it out, and thus thread breakage repair work can be easily performed, and the appearance of the sewn product is not deteriorated. Therefore, it is possible to smoothly move the work cloth without the need for a subsequent thread cutting operation by hand and without wrinkles on the work cloth.

[Brief description of drawings]

FIG. 1 is a plan view of a multi-head chain stitch sewing machine showing an embodiment of the present invention.

FIG. 2 is a plan view showing a thread take-out position of a cloth support frame in the sewing machine.

FIG. 3 is a plan view showing a sewing device of the sewing machine.

4 is a sectional view taken along line XX of FIG.

FIG. 5 is a cross-sectional view showing the operation of the thread guide member by the sewing machine.

FIG. 6 is a plan view showing a thread holding process by the sewing machine.

FIG. 7 is a plan view showing a thread cutting process by the sewing machine.

FIG. 8 is a cross-sectional view showing a thread take-out step by the sewing machine.

FIG. 9 is a cross-sectional view showing a conventional yarn breakage repairing method.

FIG. 10 is a cross-sectional view showing a defect in a normal sewing machine head in which thread breakage does not occur in another conventional thread breakage repairing method.

[Explanation of symbols]

 1 multi-head chain stitch sewing machine 2 sewing machine head 3 cloth support frame 4 needle plate 5 needle hole 6 threading hole 10 looper 11 thread holding member 12 crochet needle 20 thread cutting member 24 thread guide member 52 thread taker T thread W processed cloth

Claims (1)

[Claims] 1. At least two sewing machine heads are provided,
In a multi-head chain stitch sewing machine in which each sewing machine head is provided with a vertically moving crochet needle, when a thread breakage occurs in one sewing machine head, another normal sewing machine head holds the thread connected to the crochet above the looper. The process of cutting below the needle plate, the process of moving the work cloth together with the cloth support frame from the sewing position to the thread take-out position in all sewing machine heads to expose the thread passing hole of the needle plate, and thread breakage occurs. In the sewing machine head, the step of taking out the broken thread from the threading hole to the upper side of the needle plate and the step of moving the work cloth together with the cloth support frame from the thread take-out position to the sewing restart position in all the sewing machine heads are included. A method for repairing thread breakage in a multi-head chain stitch sewing machine.