Thread chain guiding device for overedge sewing machines

摘要

A thread chain guiding device provides a needle-thread-guide plate which extends underneath a throat plate by energizing a solenoid as needed. Thus, the needle-thread-guide plate pushes the needle threads twined around a lower looper outwardly away such that the thread chain is prevented from hanging on an inner chain-off finger when it is rotated counter clockwise. The needle-thread-guide plate is retracted during a normal stitching process by de-energizing the solenoid.