JPH075818Y2 - Safety stitch and forming mechanism of sewing machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a structure of a safety seam and a sewing machine for forming the safety seam.

[Conventional technology]

Conventionally, as this type of safety seam, a seam composed of an overlock seam and a single-thread chain seam is known. This type of seam is used in the dyeing process to connect fabrics of infinite length to fabrics of infinite length.

However, since this type of seam has overedging seams composed of two threads, it has no elasticity compared to one single-thread chain stitch, and when it is washed with water, etc. And the like are likely to occur, resulting in color unevenness in the dyeing process and the like.

Further, since the overedging seam is composed of two threads, there is a defect that when the roller is applied after the dyeing process, the seam is not dyed well and the seam is not fixed.

Also, in the dyeing process, this type of safety stitch connects the fabric edges together to make the process an infinite length.
When the process requires less tension, the single-thread chain stitches of the safety seams are unwound to eliminate the overlapped areas of the fabric even a little and to prevent uneven dyeing so that the process flows smoothly.

However, even if the single-thread chain stitch is unwound in the conventional safety seam, the overlocking seam is composed of the double chain stitch in which two threads are intricately entangled, so that the cloths are tightly tightened. However, there is a drawback that the joint portion of the cloth edge cannot be made flat.

Also, when using this seam for dyed goods, it is necessary to unravel this safety seam after the dyeing process, but it is difficult to unravel because the overlocking seam is a double ring composed of two threads. The workability was extremely poor.

Furthermore, this conventional safety seam consumes a total of three yarns, even though it is unraveled later, and thus has a drawback that the consumption amount of the yarns increases.

Therefore, due to the drawbacks of "wrinkle", "fixability", "flatness" and "difficulty of unwinding", this stitch is completely unsuitable for safety stitches such as dyed fabrics.

[Problems to be solved by the device]

The present invention was made in view of such conventional problems, and there is no difference in stretchability. Therefore, while providing a safety seam that is less likely to cause "wrinkles", such a safety seam is provided. An object of the present invention is to provide a safety stitch forming mechanism of a sewing machine that can be formed.

[Means for Solving the Problems]

In this invention, the safety seam is composed of a single-thread ring overlock stitch and an independent single-thread chain stitch, and as a means of forming this seam, it is hung on the lower surface of the needle plate near the needle hole. To form a single-thread chain stitch overlock stitch by the cooperation of the first pin and the first needle with the thread escaping groove formed along the needle hole on the lower surface of the pin and the needle plate on the pin side. And a safety stitch forming mechanism of the sewing machine, which includes a second stitch forming mechanism that forms a single thread chain stitch.

〔Example〕

In FIG. 1, reference numeral 1 denotes an upper hook looper shaft that is rotatably supported by a machine frame (not shown) along the cloth feeding direction and swings in conjunction with a main shaft (not shown). Reference numeral 2 is an arm fixed to the upper hook looper shaft 1, and 3 is a rotating piece rotatably supported by the machine frame 4, and a supporting rod 5 is slidably inserted into the rotating piece 3.

The lower end of the support rod 5 is rotatably supported by the free end of the arm 2, and the upper hook is fixed with an upper hook looper 6.

Reference numeral 7 denotes a lower looper shaft rotatably supported by the machine frame along the cloth feed direction, and is connected so as to swing in conjunction with a main shaft (not shown). Reference numeral 8 denotes a lower hook looper fixed to the lower looper shaft 7.

Reference numeral 9 denotes a single-loop looper shaft that is rotatably supported by the machine frame along the cloth feed direction, and is connected so as to swing in conjunction with the main shaft. Reference numeral 10 is a single yarn ring looper supported on the single ring looper shaft 9.

The single-thread looper 10 has a scooping groove 10A for scooping a needle thread on its abdomen.

Reference numeral 11 denotes a needle bar that is supported in the machine frame so as to be movable up and down in conjunction with the main shaft.The needle bar 11 is provided with a staggered position in the cloth feed direction and is spaced apart in the direction intersecting the cloth feed direction. Two needles one
2,13 are fixed.

Then, as shown in FIG. 7, the first needle 12 has the needle thread A inserted therethrough, and cooperates with the upper and lower hooks and loopers 6 and 8 to form a single-thread ring overlock stitch SF, and The needle thread B is inserted through the needle 13, and the single thread loop stitch S is formed in cooperation with the single ring looper 10.

Reference numeral 14 is a needle plate provided on a sewing machine bed (not shown), and has a first needle hole 15 through which the first needle is inserted and a second needle hole 16 through which the second needle 13 is inserted.

As shown in FIG. 5, a thread sabaki pin 17 is hung on the side of the lower surface of the needle plate 14 of the second needle hole 16. Then, on the lower surface side of the needle plate 14 on the pin 17 side, there is formed a thread slit escape groove 18 which is gradually narrowed from the end of the second needle hole 16 along the cloth feeding direction.

[Operation of Example]

 Next, the operation of the embodiment of the present invention will be described.

(Formation of Single Thread Ring Overlock Stitch) In FIG. 6, the first needle 12 is inserted through the cloth W, and then the needle
12 rises and a loop LA of the needle thread A is formed.

This loop is captured by the lower cagirupa 8 and moves to the lower side edge of the cloth W. After that, the needle thread A captured by the lower cagirupa 8 is captured by the upper cagirupa 6 and moved from the lower side edge of the cloth W to the cloth upper surface side so as to cover the cloth edge.

Then, as shown in FIG. 3, the needle 12 that has descended again from the raised position to the uppermost dead point is inserted into the loop LA of the moved needle thread A.

This operation is repeated to form a single-thread ring edge stitch.

(Formation of Single Thread Chain Stitch) When the second needle 13 descends and is inserted into the cloth and rises above the bottom dead center, a needle thread loop LB is formed.

The single loop looper 10 moves while scooping the needle thread loop LB with the rake groove 10A.

When the single ring looper 10 is retracted, the thread sabaki pin 17 scoops and temporarily hooks one side of the needle thread B scooped by the looper 10. Then, in the rake groove 10A on the abdomen of the looper 10, the needle thread is retracted, and the needle 13 is inserted into the triangular loop formed by the thread sabaki pin 17, the abdomen of the looper 10 and the needle thread loop knot at the tip. , This loop is scooped by the needle 13.

Then, when the looper 10 is finally retracted, the needle thread hooked on the thread sabaki pin 17 and the needle thread hooked on the looper 10 also come off, and the needle is lowered to the bottom dead center to return to the initial state.
By repeating this operation in sequence, a single-thread chain stitch is formed.

According to the embodiment of the present invention, when the triangular loop is formed, the thread slit escape groove 18 is formed.
As a result, the thread from the knot point of the needle thread loop to the pin 17 enters into the groove 18, so that the triangular loop is opened more than the conventional one and the needle 13 surely scoops the loop and skips. The effect is that it can be prevented.

[Effect of device]

According to this invention, the seam is composed of a chain stitch overedging seam made of a single thread and a single thread chain seam which is independent in parallel with the overedging seam at a distance. Since the eye is a single thread ring, it is extremely easy to untie, the work efficiency is improved, and since there is no roughness in the seam, there is an effect that the cloth stitching portion has no unevenness and beautiful dyeing can be achieved.

Furthermore, since it is composed of two yarns in total, there is an effect that the amount of yarn consumption is small.

Further, according to the stitch forming mechanism of the present invention, since the thread escape groove is formed in the vicinity of the needle hole, the needle can surely scoop the needle thread. This has the effect of being able to solve the drawback that eyes and jumps have occurred because of the restrictions on the.

Furthermore, according to the safety seam according to the present invention, since the overlock seam is composed of a single thread, the tension is not so much, and the joint portions of the cloth can be stretched to the extent that they do not overlap each other. There is an effect that the connected state can be maintained while the spliced part is flat, and in the dyeing process,
It is possible to prevent the disadvantage that the dyeing is not completely dyed on the cloth due to the conventional polymerized portion.

[Brief description of drawings]

FIG. 1 is a front view of an apparatus according to an embodiment of the present invention, FIG. 2 is a plan view of an essential portion of the apparatus according to an embodiment of the present invention, and FIGS. 3 and 6 are formation of single-thread chain stitch overlock stitches. Fig. 4 (a), (b), (c), (d) is a perspective view showing the formation of a single thread chain stitch, and Fig. 5 (a) is a second needle hole. FIG. 5 (b) is a right side view of FIG. 5 (a), FIG. 5 (c) is a sectional view taken along the line AA of FIG. 5 (a), and FIG. It is a perspective view showing the structure of the safety seam. 6 ... Upper hook looper 8 ... Lower hook looper 10 ... Single ring looper 11 ... Needle bar 12 ... First needle 13 ... Second needle 14 ... Needle plate 17 ... Thread slit pin 18 ... Thread slit escape groove

Claims (2)

[Scope of utility model registration request] 1. A chain stitch overlock seam in which a fabric edge is overed with a single thread,
A safety stitch for a sewing machine, which is spaced apart from the single-thread chain stitch overedging seam and is composed of independent single-thread chain stitches parallel to and independent of the single-thread chain stitch overedging seam. 2. A needle bar which is supported by a sewing machine frame so as to be movable up and down, and which moves up and down in conjunction with a main shaft, and a first bar which is provided on the needle bar so as to be separated from each other in a direction intersecting the cloth feed direction.
Needles and second needles, a needle plate that is supported on the sewing machine bed, and has first and second needle holes through which the first and second needles are inserted, and interlocks with the spindle. The lower hook looper, which supports the needle thread loop of the first needle, and the lower hook looper that interlocks with the main shaft and crosses the lower hook looper below the needle plate. The upper hook looper supported on the sewing machine frame so that it can swing up and down to the position intersecting with the needle, and the sewing machine frame below the needle plate so that it can swing in conjunction with the main shaft, and the needle thread loop of the second needle A single ring looper to be caught, a thread sabaki pin provided on the lower surface of the needle plate near the second needle hole through which the second needle is inserted, and a thread sabaki pin on the lower surface of the needle plate on the side of the second needle hole. Thread slit relief groove formed along the cloth feed direction from the first needle, the lower hook looper and the upper hook looper. Forming a single-thread ring edge overlock seam on the cloth edge in cooperation with
A mechanism for forming a safety seam of a sewing machine, characterized in that a single thread chain stitch is formed by the needle of the machine and a single loop looper.