JPS6111635B2 - - Google Patents

Description

Detailed Description of the Invention The present invention automatically cuts the decorative thread instead of the needle thread at the end of sewing on a flat multi-needle sewing machine such as a flat three-needle sewing machine or a flat two-needle sewing machine. This invention relates to an automatic decorative thread cutting device for a flat multi-needle sewing machine, which is characterized by gripping the end of the thread on the decorative thread path side.

Conventionally, in flat 3-needle sewing machines, flat 2-needle sewing machines, etc., when the pedal is pressed back at the end of sewing, the rotation of the sewing machine stops and the needle thread and looper thread are automatically and mechanically severed. The place is equipped so that
There is no way to automatically cut only the decorative threads,
When the needle thread and looper thread are cut as described above, the fabric presser foot automatically rises, allowing the worker to extend the finished fabric from the bottom of the presser foot to the rear left and remove the decorative threads that are still being sewn. The worker manually cuts the material using hand scissors near the front and back of the fabric retainer.
It was the first time that a sewn product could be removed from a sewing machine, and in today's era of ultra-high speed sewing machines, people were wasting time cutting decorative threads.
In addition to being inefficient, this method also has various drawbacks, such as requiring a highly skilled worker to cut the ornamental threads.

Incidentally, Japanese Patent Publication No. 55-40530 is also disclosed, but this disclosure relates to a needle thread cutting device, and although the device can cut needle threads, it cuts decorative threads which are mechanically completely different. That is impossible.

Furthermore, in a needle thread cutting device, the cut end is naturally held through the thread hole and does not interfere with the start of the next sewing, but decorative threads do not have a thread hole and do not have the function of holding the cut end. From this point of view, this device is unsuitable for use in cutting decorative threads.

However, in the present invention, the decorative thread is mechanically and automatically cut in the same way as the needle thread and the looper thread, and the cut end of the decorative thread on the thread path side is mechanically grasped and held, making it convenient for the next sewing. The results are remarkable, as even an unskilled person can cut decorative threads with high efficiency without wasting time.

A detailed description will now be given with reference to the accompanying drawings showing an example of implementation.

1 is needle thread, 2 is looper thread, 3 is decorative thread, 4 is 3
Main needle, 5 is the decorative thread looper, 6 is the decorative thread path, 7 is the fabric cloth, 8 is the looper of the looper thread, 9 is the sewing end of the decorative thread, 10 is the decorative thread on the sewing end side, 11 is the thread path The decorative threads on the side, 12 are thread hooks of the decorative thread looper, and 13 are arrows indicating the sewing direction of the fabric. 1
Reference numeral 4 denotes a decorative thread trimming device mounting plate, which is fixed directly or indirectly on the sewing machine body. Reference numeral 15 denotes a longitudinal position adjustment plate, which is attached to the decorative thread trimming device mounting plate 14 through a long hole 16 and a screw rod 17 so that the longitudinal position can be adjusted. Reference numeral 18 denotes a vertical position adjustment plate, which is attached to the longitudinal position adjustment plate 15 through a long hole 19 and a screw rod 20 so as to be vertically adjustable. Reference numeral 21 denotes a solenoid for operating the upper knife for trimming the decorative threads, and is attached directly or indirectly to the vertical position adjustment plate 18. Reference numeral 22 denotes a thread trimming knife device mounting plate, which is directly or indirectly attached to the main body with knife device mounting screws 23. Reference numeral 24 denotes an upper knife mounting plate for trimming threads, and an upper knife for trimming threads 25 is attached to the surface thereof.
A hook-shaped cutting edge 26 is formed at the tip of the upper scalpel. Reference numeral 27 denotes an upper knife attachment plate return spring, which is installed between the immovable ornamental thread trimming knife device mounting plate 22 and the ornamental thread trimming upper knife attachment plate 24, which is provided so as to be movable forward and backward. Reference numeral 28 denotes a lower knife for trimming decorative threads, the base end of which is attached to the immovable mounting plate 22 of the decorative thread trimming knife device, and the tip thereof is equipped so as to come into contact with the lower surface of the distal end of the return stroke of the upper knife 25, so that the blade tips of both blades come into contact with each other. This is used to cut the decorative threads. Reference numeral 29 denotes a thread pinching leaf spring, the base end of which is attached to the immovable decorative thread trimming knife device mounting plate 22, and the distal end of the thread clipping knife device mounting plate 22 so as to come into pressure contact with the upper surface of the upper scalpel 25 when returned. The end of the cut decorative thread on the thread path side is grasped and held between the sewing machine and the knife 25, and is held conveniently at the beginning of the next sewing process.
30 is the cloth presser, and 31 is the sewing end side. 3
2 shows the state of the thread after the decorative thread has been cut.

The present invention is constructed as described above, and when one sewing operation is completed and the pedal connected to the drive motor of the sewing machine is stepped back, the sewing machine stops at the predetermined top dead center of the needle bar, and the needle thread 1 and looper The thread 2 is cut by means of known equipment. Then, the solenoid for operating the decorative thread trimmer upper knife is activated, and against the elasticity of the return spring 27, the decorative thread trimmer upper knife is moved between the thread hook part 12 for threading the decorative thread looper and the sewing end part 9. The thread advances to the middle of the decorative thread stretched over the thread, then the solenoid no longer pulls the thread, and the elasticity of the spring 27 causes the upper knife 25 to move.
moves in the return direction. At this time, the decorative thread 3 is hooked onto the hook-shaped cutting edge 26 of the upper knife, and is automatically cut between it and the lower knife 28 waiting below. However, when cutting, the decorative thread produced by the decorative thread looper of this multi-needle sewing machine has a triangular shape, and the triangular shape depends on the number of needles, needle width, type of machine, etc. It also changes depending on the locus of movement of the looper.
5 needs to be inserted into the triangular shape of the ornamental thread 3 at the appropriate vertical and longitudinal positions. To do so, loosen the screw rod 17 and insert the long hole in the longitudinal position adjustment plate 15. 16, the adjustment plate 15 can be moved back and forth, and in order to adjust the vertical position of the decorative thread trimmer upper knife 25, the screw rod 20 is loosened and the length of the vertical position adjustment plate 18 is adjusted. Hole 19
The adjustment is made by moving the adjustment plate 18 up and down. At this time, since there is a thread pinching plate spring 29 above the lower knife 28 that presses against the surface of the upper knife, the cut end of the decorative thread 11 on the thread path side is pinched between the upper knife 25 and the thread pinching plate spring 29. This is done in preparation for the next sewing start.

In the present invention, the needle thread 1, the looper thread 2, and the decorative thread 3 are automatically and mechanically cut by the above-described action, and even an unskilled person can cut the decorative thread 3 with high efficiency, which is very effective. It is.

[Brief explanation of the drawing]

The attached drawings show an example of carrying out the present invention, in which Fig. 1 is a perspective view of the main part, Fig. 2 is an enlarged perspective view of the thread row, and Fig. 3 is a side view showing the relationship between the decorative thread and the upper and lower knives. In the figure, A shows the state in which the decorative thread cutting knife is in the return stroke, and B shows the state immediately after cutting the decorative thread. FIG. 4 is a perspective view of the main part when the hook-shaped cutting edge is hooked with a decorative thread and is in the returning state. 1... Needle thread, 2... Looper thread, 3... Decorative thread,
4... Needle, 5... Decorative thread looper, 6... Decorative thread path,
7...Fabric cloth, 8...Looper thread looper, 9
...Sewing end part of the decorative thread, 10... Decorative thread on the end side of sewing, 11... Decorative thread on the thread path side, 12... Thread hook part,
13...Arrow indicating the sewing progress direction of the fabric, 14...
Decorative thread trimming device mounting plate, 15... Front-rear position adjustment plate,
16, 19...Long hole, 17,20...Screw rod, 18
. . . Vertical position adjustment plate, 21 . . . Solenoid for operating the upper knife for thread trimming, 22 . . . Mounting plate for the thread trimming knife device, 23 . . . Screw for setting the knife device mounting plate, 24 . . . 25... Decorative thread trimming knife, 2
6... hooked cutting edge, 27... upper knife attachment plate return spring, 28... lower knife for decorative thread trimming, 29... thread pinching plate spring, 30... fabric presser, 31... sewing end side,
32... Thread after decorative thread cutting.

Claims (1)

[Scope of Claims] 1. At the end of sewing, the intermediate part of the decorative thread on the sewing end side stretched between the thread hook of the decorative thread looper and the sewing end part of the decorative thread is mechanically applied from diagonally upward and backward. Equipped with a hook-shaped upper knife for trimming decorative thread that moves forward and backward, and equipped with a lower knife that is stationary during the backward movement of the upper knife. When the thread looper stops at the dead center of the left swing, the decorative thread is mechanically cut at the appropriate intermediate position of the decorative thread stretched between the thread hook of the decorative thread looper and the right end needle stitch at the end of sewing. A feature is that the upper scalpel is inserted, the decorative thread is hooked on the hooked cutting edge of the upper knife, and the decorative thread is pulled in the return direction, and the decorative thread is cut between it and the waiting lower knife. Automatic decorative thread cutting device for flat multi-needle sewing machines. 2 At the end of sewing, a hook that is stretched between the thread hook part of the decorative thread looper and the sewing end part of the decorative thread is mechanically moved forward and backward from the diagonal upward and rearward direction to the middle part of the decorative thread on the sewing end side. Equipped with an upper knife for trimming decorative thread, equipped with a lower knife that is stationary during the forward and backward movement of the upper knife, and equipped with a thread pinching plate spring above the lower knife that presses against the upper surface of the upper knife. An automatic decorative thread cutting device for a flat multi-needle sewing machine, characterized in that the decorative thread end is held in a fixed position after the decorative thread is cut. 3. Attach an upper knife operation solenoid directly or indirectly to the sewing machine body, provide an upper knife that is moved forward by the solenoid, and equip the upper knife with a return spring so that the upper knife does not move downward during the return stroke of the upper knife. A knife is placed in place, and a thread pinching plate spring is installed above the lower knife so as to press against the upper surface of the upper knife, and after cutting the decorative thread,
An automatic decorative thread cutting device for a flat multi-needle sewing machine, characterized in that the decorative thread end is held in a fixed position.