DE2914117

The present invention relates to an improved thread control mechanism for chain-stitch sewing machines. The present invention is adapted to apply a quick and effective clamping action to the sewing thread of the machine in timed relation with the rotary or oscillatory movements of the stitch forming instrumentalities. The mechanism's clamping force magnitude may be selectively regulated to exceed the tensile strength of the particular thread being used and is effective to break the thread should it become wound about an operable rotary shaft of the machine. The present invention includes a rotary actuating member for moving a thread engaging member between two extreme positions so as to entrap and intermittently clamp the thread at a location interposed between the stitch forming instrumentalities and the thread supply source.