摘要 |
A lockstitch sewing machine utilizing a needle looper to extend upwardly through a work material to grasp an upper thread and pull it downwardly through the work material to a looptaker which casts the upper thread about a lower thread in order to form a lockstitch. When the needle looper is in an upper position to catch an upper thread, a hook needle is exposed and thread is deflected into the hook thereof. As the needle looper is retracted to a depressed position the hook needle is moved to a guard position so as to retain the upper thread therein during transit. When the needle looper is at its lower position, the hook is again exposed to release its thread to a looptaker for concatenation with a lower thread.
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