摘要 |
A lock stitch sewing machine having a rotary loop taker adapted to carry a loop of thread about a stationary bobbin thread case. The bobbin thread case is restrained from rotation by a finger which is disposed between abutments in the bobbin thread case for opening a passage to allow the needle thread loop past the bobbin thread case rotation restraining means, the rotation restraining finger is vibrated at a frequency greater than four cycles per rotation of the loop taker.
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