Lock stitch sewing machine having a rotatable shuttle

摘要

A lock stitch sewing machine, comprises a sewing machine housing having a bed plate with an opening therethrough, with a needle reciprocating on one side of the opening and a rotatably mounted shuttle on said housing on the opposite side of the opening for cooperation with the sewing needle. The shuttle includes a bobbin case with a shuttle rotatable in said case which has a thread loop pickup point. A supply of thread is located in the case on a spool and a case carrier having a catch shoulder for engaging the thread and also having a carrier stop is rotatable in the bobbin case for limited rotation between defined limits. The limits are defined by stop surfaces on a stop fixture. The stop fixture comprises a spring having a free end portion which is disposed in a plane parallel to the rotation plane of the shuttle and the transversely extending stop surface defining a thread guide portion for a thread guide edge which extends obliquely to the pull off path of the needle thread loop. The thread guide edge and a radially extending stop member edge of the carrier stop diverge from the straight interior stop surface in a direction opposite to the pull off direction of the needle thread loop.