JP3486820B2 - Thread trimming method in chain stitching - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of cutting a thread at the end of sewing when chain sewing is performed on a cloth.

[0002]

2. Description of the Related Art In the case of performing chain sewing, a hook needle that repeatedly moves up and down when the thread that has been sewn is cut to finish sewing with one thread and start sewing with another thread. The operation of the hook needle is stopped in a state where the thread is raised, and the thread is cut by the thread cutting device provided at a predetermined position under the bed. In this case, the yarn cutting device is provided under the bed at a position close to the bed in order to shorten the length of the yarn remaining under the fabric in a state of being connected to the fabric.
If it is possible to cut the length of the thread remaining in the state of being connected to the cloth as described above, for example, when sewing while exchanging the thread for various colors in one handle, the thread is cut every time the color is changed. Even if the ends of a large number of threads that have been hanged remain under the cloth, they are all short, so that the troublesome work of cutting off the hung threads in a later step can be eliminated.

[0003]

However, the final position of one sewing operation, for example, the position of the end of sewing of one pattern, or even the continuous sewing of one pattern once is completed and then the next sewing is performed. At the position where the starting point is distant, it is necessary to attach the end of the thread that is continuous with the cloth to the cloth in order to prevent the seam from unraveling in the post-process. If cutting had been performed, there was a problem that it was very difficult to tie the work together.

The present invention has been made in order to solve the above-mentioned problems (technical problems) of the prior art, and the purpose thereof is to increase the length of the thread remaining in the state of being connected to the cloth at the final sewing position. (EN) A thread cutting method in chain sewing in which the thread can be cut in the above state and the end of the remaining thread can be easily attached to a cloth in a subsequent step.

In the thread trimming method for chain sewing in the present invention, the sewing hook needle arranged above the bed is lowered to the looper arranged below the bed through the cloth on the bed and the needle hole of the bed, and the hook needle is used by the looper. After hooking the thread on the hook portion, the hook needle is raised to pull the thread from the looper to the upper surface side of the cloth in a loop shape by the hook portion, and the cloth is laterally moved by one stitch in the pulled state. In the method of performing chain sewing on the cloth by pulling up the thread through the loop of the thread that has been pulled up before, in the final stitch of the cloth, the thread is pulled by the hook portion. With the thread pulled up to the upper surface side, the thread that has been pulled up goes through the portion hooked to the hook portion from the end on the front needle eye side to the bed. The length of the thread between the cloth and the needle hole is adjusted by the needle withdrawing member so that the length up to the part that penetrates the needle hole is longer than the length of the same part when the thread is pulled up at the middle stitch. The thread between the needle hole and the looper is cut by a thread cutting device provided at a predetermined position under the bed in a state where the thread is pulled out to the side from the position above the hole. Further, preferably, the hook needle for sewing arranged above the bed is lowered to the looper arranged below the bed through the cloth on the bed and the needle hole of the bed, and after hooking the thread on the hook portion of the hook needle by the looper, Raising the hook needle to pull the thread from the looper to the upper surface side of the cloth in a loop shape by the hook portion, and laterally moving the cloth by one stitch in the pulled state are repeated, and the thread is pulled up. In the method of sewing a chain on the cloth by carrying out the thread through the loop of the thread pulled up before, in the final stitch for the cloth, the thread is pulled up to the upper surface side of the cloth by the hook portion, For the thread that has been pulled up, measure the length from the end on the front needle eye side to the part that passes through the part hooked on the hook part and penetrates the needle hole of the bed. To be longer than the length of the portion in time of pulling the thread in the eye, of increasing the open eye needle to a position higher than the raised position during normal sewing
In this state, the thread between the needle hole and the looper is cut by a thread cutting device provided at a predetermined position under the bed.

[0006]

[Function] At the last stitch of sewing, when the thread is pulled up to the upper surface side of the cloth by the hook, the portion of the pulled-up thread that is hooked on the hook from the end on the front stitch side is pulled. The length up to the part that passes through the needle hole of the bed is longer than the length of the same part when pulling up the thread at the middle stitch, and in that state, the thread between the needle hole and the looper under the bed. Disconnect. Therefore, the length of the yarn remaining after being cut in a continuous state with the cloth, that is, the length from the front end on the stitch side to the cut end is long. When this thread is long, it becomes easy to tie it to the cloth in a later step.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6, reference numerals 1 to 16 represent respective members in a known chain stitch sewing machine, 1 is a bed, and is composed of a plate 1'attached to a base frame of the sewing machine and a needle plate 2. There is. The throat plate 2 is attached to the bed plate 1'with set screws 3. Reference numeral 4 denotes a needle hole, and 5 denotes a threading hole. 4a is a needle hole having a different diameter, 5a is a threading hole provided corresponding to the needle hole.
When the needle hole 4 and the threading hole 5 are rotated by 0 °, the needle hole 4 and the threading hole 5 are used by being exchanged with them. Reference numeral 6 is a lid for closing a maintenance hole formed in the bed plate, which is attached with a fixing screw 7. 8 is a vertically movable hook needle for sewing, and 9 is a hook portion. The hook needle 8 is repeatedly moved up and down between a normal ascending position indicated by reference numeral P1 in FIG. 8 (A) and a descending position reaching the looper 12 by a commonly known lifting mechanism (not shown). As shown by symbol P2 in FIG. 9 (G), it is possible to raise to a position higher than the raised position P1 (see, for example, Japanese Unexamined Patent Publication No. 5-15679). 11 is a looper base, which is provided so as to be movable laterally with respect to the base frame of the sewing machine. 12 and 12 ... are a plurality of loopers attached to the looper table 11,
By the lateral movement of 11, the needles 4 are exchangeably arranged so as to be positioned immediately below the needle hole 4. As shown in FIG. 1, each looper 12 is at a lowered position where it is retracted from the path of the reciprocating movements 15a and 15b of the pulling member 15, and when it is sewn, it is raised near the needle plate 2 as shown in FIG. 8A. Up and down positions are individually changed between the positions. Each looper is loaded with different types of threads (eg, color, thickness, properties, etc.).
Reference numeral 13 is a drive rod for driving the looper base 11 in the lateral direction. 14 is a thread cutting device provided under the throat plate 2
A pulling member 15 capable of reciprocating in the directions 15a and 15b and a cutter body 14a for cutting a thread (see FIG. 8B) are provided.

Next, 17 is a recess for accommodating the wiping member formed in the upper surface of the bed plate 1 ', and 18 is a bearing hole formed in the bed plate 1'. Reference numerals 19 and 20 are guide pieces attached to the bed plate 1 ', and their upper surfaces are arcuate guide surfaces 19a and 20a as shown in FIGS. 7 and 6, respectively.
Reference numeral 21 denotes a wiping member, which can be laterally moved along the upper surface of the needle plate 2, and in this example, for example, is configured to perform an arc motion along the upper surface of the needle plate 2 around a shaft body 22 provided at the base portion. . You may make it move in parallel along the upper surface of the needle plate 2. The shaft body 22 is supported by the bearing hole 18 so as to be rotatable and movable in the axial direction. Reference numeral 23 shown in FIG. 4 is an urging member for urging the wiping member 21 toward the bed plate 1'side, for example, a spring for urging downward in this example, which is a spring receiver constituted by a part of the bed plate 1 '. Spring seat 25 attached to part 24 and shaft 22
It is interposed between and. Reference numeral 26 is a passive lever fixed to the shaft body 22. 27 is a fitting hole formed at a position corresponding to the guide piece 20. Next, reference numeral 30 shown in FIG. 31 is a motor in the mechanism, 32 is a cam, and has a cam groove 32a in the periphery. Reference numeral 33 is a drive lever, which is axially supported by the intermediate portion 33c and has a follower provided at one end.
33a is engaged with the cam groove 32a, and the engaging piece 33b provided at the other end
Is engaged with an engaging hole 26a formed in the passive lever 26.
In this drive mechanism 30, one rotation of the cam 32 by the motor 31 causes the driving member 33 and the passive lever 26 to move the wiping member 21.
Makes one round trip in the direction of the arrow.

The operation of the paying member 21 is as follows.
In the state of FIG. 7A, that is, after the sewing of the cloth 35 by the well-known operation of the looper 12 and the hook needle 8 is completed and the thread 36 is cut by the cutting device 14, the wiping member 21 drives the driving mechanism 30 thereof. Reciprocates as described above. In this case, in the course of the forward movement, first, the wiping member 21 is guided by the guide surfaces 19a and 20a of the guide pieces 19 and 20 from the state of FIG. 6A and FIG. ) And as shown in FIG. 7B. Subsequently, the payout member 21 is shown in FIG.
Along the upper surface of the needle plate 2 as indicated by the arrow 37 on the needle hole 4
It moves laterally through the position where it overlaps. Due to this lateral movement, among the cut yarns 36, the yarn 36a on the side connected to the cloth 35, that is, the yarn 36a remaining in the needle hole 4 as shown in FIG. As shown in C), it is pulled out from the needle hole 4,
It is in a state of being along the lower surface of the cloth 35. Post-payment material 21
Moves back and returns to the position inside the recess 17.

Next, FIGS. 8, 9 and 10 showing the process of sewing the cloth 35 by the sewing machine will be described. Looper
By the well-known operation of the hook 12 and the hook 8, the cloth 35 is sewn by the thread 36 supplied through the looper 12 as shown in FIG. That is, the hook needle 8 descends from the raised position P1 to the lowered position through the needle hole 4, and then the looper
12 rotates, the thread is hooked on the hook portion 9, and then the hook needle 8 rises toward the top dead center to pull the thread 36 from the looper 12 to the upper surface side of the cloth 35 in a loop shape. The pulling is done through the loop 38 of previously pulled thread. After the thread is pulled up, the cloth tension frame holding the cloth 35 is laterally moved on the bed plate 1'by the size of one stitch of the sewing, and the cloth 35 is laterally moved by the same size. Such operations are repeated and the chain sewing 36b is performed.

The above-mentioned sewing is performed to complete the thread exchange point, that is, the sewing with one thread 36 is completed, and the next different thread
The operation when the point to start sewing by 36 'is reached is as follows. When reaching the thread exchange point, the hook needle 8 stops at the raised position P1 as shown in FIG. The height H1 is, for example, 2 to 3 mm. Next, as shown in FIG. 8B, the pulling member 15 moves forward as indicated by an arrow 15a to bring the yarn 36 between the needle hole 4 and the looper 12 to the cutter body 14a, and the yarn 36 36 is held by a holding tool 16 which is individually provided corresponding to each looper 12, and the cutter body 14a cuts the thread. In this case, the length L1 of the yarn 36a remaining in the state of being connected to the cloth 35 is, for example, 20 to 25 m.
m. After that, the pulling member 15 moves back in the direction of the arrow 15b. Next, the wiping member 21 moves forward as described above, and becomes the state as shown in FIG. Along with the movement of the above-mentioned sweeping member 21 (even after the movement of the sweeping member 21 is finished), the looper table
The lateral movement of 11 causes a looper 12 'directly below the needle hole 4 as shown in FIG. 9 (D) to be loaded with another type of thread 36' to be used for sewing next. Reference numeral 16 'is a thread holder provided for the looper 12'. After returning the sweeping member 21, as shown in FIG. 9 (E), the hook 8 and the new looper 12 '.
By starting the operation of, sewing with another type of thread 36 'is started. After the sewing with the thread 36 'is started, the final loop 38a of the previous thread 36 is changed to the first needle 39 by sewing the second stitch, the third stitch, ... Second stitch
Sew on fabric 35 with thread 36 'between 40.

Next, as shown in FIG. 9G, the cutting of the thread 36 'when the final stitch 41 of the sewing by the thread 36' is reached,
In the state where the thread 36 ′ is pulled up to the upper surface side of the cloth 35 by the hook portion 9, among the pulled-up thread 36 ′, from the end 43 on the front needle eye 42 side, through the portion hanging on the hook portion. Length L3 up to the part 44 that penetrates the needle hole 4 of the bed
Is made longer than the length L4 of the same portion when the thread 36 'is pulled up at the middle stitch as shown in FIG. 9 (F),
In that state, as shown in FIG. 10H, the thread between the needle hole 4 and the looper 12 'is cut by the thread cutting device 14 at a predetermined position under the bed.
Cut 36 '. For example, as shown in FIG. 9 (G), when the final stitch 41 is reached, the hook 35 is not moved laterally and the hook needle 8 is moved to the long pull-out position P2 higher than the normal raised position P1. Up to. The height H2 is, for example, about 20 mm. When pulled up in this way, the above edge 43
The length L3 from the above portion to the above portion 44 can be made longer than the length L4 of the portion when the thread 36 'is pulled up at the middle stitch. By cutting in this state as shown in FIG. 10H, the length L2 of the yarn 36a 'from the end 43 to the end 45 cut by the cutter body 14a is long, for example, 60 to 65 mm. It will be about. The relationship of the operation timing of each member when the yarn is cut at the final stitch 41 is as shown in FIG.

When all the sewing operations for the cloth are completed, the cloth 35
After lifting the sewing machine from the sewing machine,
In order to prevent the remaining thread 36a 'connected to the cloth at 41 from being unwound, the thread 36a' is attached to the cloth 35 as shown in FIG. 10 (I). As is generally known, the operation is performed so that the thread 36a 'between the portions indicated by the reference numerals 43 and 45 in FIG. 10 (H) is entirely clothed as indicated by the reference numeral 46 in FIG. Pull it to the upper surface side of 35, and then pass the thread 46 under the cloth 35 at a position 47 different from the final stitch 41, and form a knot 48 there so that the thread 36 ′ does not come out of the cloth 35. To do. After completion of the staking, the cloth 35 is removed from the embroidery frame, and the work is completed.

Next, FIG. 12 showing a different embodiment of the present application will be described. This example shows the last stitch stitch for sewing on the cloth 35.
At 41, in a state where the thread 36 ′ is pulled up to the upper surface side of the cloth 35 by the hook portion 9 of the hook needle 8, among the pulled up threads, the thread 43 ′ is hooked on the hook portion 9 from the end 43 on the front needle eye 42 side. The following shows a different example of a method in which the length from the portion passing through the needle hole 4 of the bed to the portion 44 passing through the needle hole 4 is made longer than the length of the same portion when the thread 36 'is pulled up at the middle stitch. is there. In this example, at the last stitch 41 of sewing, the hook needle 8 is stopped to move up to the normal rising position P1 as shown in (A). Then cloth as shown in (B)
The yarn 49 between the needle 35 and the needle hole 4 is pulled out laterally from the position on the needle hole 4 by the yarn drawing member 50. As the yarn drawing member 50, the above-mentioned wiping member 21 can be used. The pull-out amount of the yarn can be set by setting the forward movement distance of the wiping member 21. Next, as shown in (C), cutting is performed by the cutting device 14 in the same manner as in the previous embodiment while maintaining the drawn state. The relationship of the operation timing of each member in the case of cutting the yarn at the final stitch is as shown in FIG. In addition, the parts which are considered to have the same or equivalent configurations as those in the previous figure in terms of function are denoted by the same reference numerals as those in the previous figure, and redundant description is omitted.

[0015]

As described above, according to the present invention, the yarn 36 remaining in the state of being continuous with the cloth 35 at the final sewing position.
The yarn 36 'can be cut so that the length of a'becomes longer, and as a result, there is an effect that the work of clasping the remaining yarn 36a' to the cloth 35 in the subsequent step can be facilitated.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a chain stitch sewing machine.

FIG. 2 is a plan view showing a state near the needle plate on the upper surface of the bed plate in the chain stitch sewing machine.

FIG. 3 is an exploded perspective view showing a relationship between a wiping member, a bed plate and a needle plate.

FIG. 4 is an enlarged sectional view taken along line IV-IV in FIG.

FIG. 5 is a mechanism diagram showing a drive mechanism of a displacing member.

6A is an enlarged sectional view taken along line VI-VI in FIG.
FIG. 6B is a cross-sectional view showing a state at the start of operation of the wiping member.

7A, 7B, and 7C are sectional views for explaining the operation of the wiping member.

8A, 8B, and 8C are explanatory views of a yarn cutting operation at a yarn exchange point.

9 (D) and 9 (E) are diagrams for explaining a sewing start operation at a thread exchange point, FIG. 9 (F) is a diagram for explaining the operation of the hook needle at an intermediate stitch, and FIG. 9 (G) is a diagram for explaining the operation of the hook needle at the last stitch.

FIG. 10 (H) is a diagram showing a cut state of the yarn at the final stitch, and (I) is a diagram showing a state in which the yarn is tied to the cloth.

FIG. 11 is a time chart showing the operation of each member of the sewing machine in the process from FIG. 9 (G) to FIG. 10 (H).

12A, 12B, and 12C are views showing an embodiment in which the operation at the end point of sewing is different.

13 is a time chart showing the operation of each member of the sewing machine in the process of FIG.

[Explanation of symbols]

8 hooks 9 Hook 12 looper 35 cloth 36,36 'thread

Claims (2)

(57) [Claims] 1. A sewing hook needle arranged above the bed is lowered through a cloth on the bed and a needle hole of the bed to a looper arranged below the bed, and after the looper hooks a thread on the hook portion of the hook needle, Raising the hook needle to pull the thread from the looper to the upper surface side of the cloth in a loop shape by the hook portion, and laterally moving the cloth by one stitch in the pulled state are repeated, and the thread is pulled up. In the method of sewing a chain on the cloth by performing it through the loop of the thread pulled up before, in the final stitch of the cloth, when the thread is pulled up to the upper surface side of the cloth by the hook portion, the yarn is pulled, the length from the end of the previous stitch side to the portion extending through the needle hole of the bed through a portion hanging on the hook, the middle of the stitch So as to be longer than the length of the same part in when you pull up the thread at, and cloth
Remove the thread between the needle hole and the side from the position on the needle hole by the thread withdrawing member.
A thread cutting method in chain sewing, wherein a thread cutting device provided at a predetermined position under a bed cuts a thread between a needle hole and a looper in a state of being pulled out to one side . 2. A sewing hook needle arranged above the bed is lowered through a cloth on the bed and a needle hole of the bed to a looper arranged below the bed, and after the looper hooks a thread on the hook portion of the hook needle, Raising the hook needle to pull the thread from the looper to the upper surface side of the cloth in a loop shape by the hook portion, and laterally moving the cloth by one stitch in the pulled state are repeated, and the thread is pulled up. In the method of sewing a chain on the cloth by performing it through the loop of the thread pulled up before, in the final stitch of the cloth, when the thread is pulled up to the upper surface side of the cloth by the hook portion, the yarn is pulled, the length from the end of the previous stitch side to the portion extending through the needle hole of the bed through a portion hanging on the hook, the middle of the stitch As it is longer than the length of the portion in time of pulling the yarn at, the open eye needle
Up to a position higher than the raised position during normal sewing.
A thread cutting method in chain sewing, characterized in that the thread between the needle hole and the looper is cut by a thread cutting device provided at a predetermined position under the bed in the raised state .