Why does the rotary shuttle of Straight Buttonhole Machine entangle thread?

When the Straight Buttonhole Machine is in use, there are always some winding problems, especially the winding of the rotary shuttle of the sewing machine. Here are 6 common problems:

1. If the machine is used for a long time, the second wire clamp and wire hook grind out small grooves or form burrs, resulting in poor surface line and block. Because the 781 upper thread is low tension, this little block is enough to have a great impact on the face line tension.

If the tension of the second thread gripper is too large at this time, it is easier to break the thread. Generally, the thread breaking head will be here, and the remaining surface thread will be wound on the rotary shuttle; If the spring force of the take-up spring is too small, the excess surface thread cannot be collected, and the formation of stitch is unstable, which will also occur. In addition, it is worth noting that the spring force of the take-up spring of the machine should be slightly larger than that of the flat sewing machine.

2. As the shuttle shell has been used for a long time, the matching part between the shuttle door and the rotary shuttle frame shaft is seriously worn, which makes the shuttle shell outward as a whole, so that the surface thread is hooked to the shuttle shell or the shuttle skin adjusting screw hooked to the shuttle shell.

3. The bobbin thread is too close to the bobbin thread surface, especially when the bobbin thread is pressed too close to the bobbin thread surface.

4. The fixed position of the bottom cutter is wrong. Sometimes, in order to make it cut the bottom line well, move the lower scissors to increase the "bite" with the moving scissors. Since the fixed knife moves to the needle plate hole, the thread to the right row of the face will touch the fixed knife and break the thread, and the broken thread will wrap around the rotary shuttle.

5. If the top thread is too loose, the Straight Buttonhole Machine is easy to roll and wind on the shaft behind the rotary shuttle.

6. Attention should be paid to the adjustment of the positioning hook - the outer opening and inner opening of the contact part between the positioning hook and the wire hook of the rotary shuttle frame should be flat.

These 6 problems are often seen in the rotary shuttle of the Straight Buttonhole Machine. Sometimes it is this small problem that leads to errors in sewing, so we must solve them in this way when we encounter