| 摘要 |
The machine has the usual upper thread needle, and lower-thread hook reciprocating transversely and oppositely to an upper hook, which manipulates the lower thread above the fabric and which is forked. The lower hook has a flat needle-contacting face on one side, and on the other side has a wedge-shaped pointed projection through which thread passes, and which has a guide face, of inclined form for cooperation by light contact with a matching curved and bent portion of the upper hook. The curved and bent portion engages and pulls out the thread of the lower hook projection.
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