Control mechanism for lock stitch sewing machines

Claim 1

IN A SEWING MACHINE HAVING A FRAME, A THREAD CARRYING NEEDLE CARRIED IN SAID FRAME, A LOOP-TAKER JOURNALED IN SAID FRAME, A THREAD CARRYING BOBBIN JOURNALED IN SAID LOOP-TAKER, A DRIVE MEANS OPERATIVELY INTERCONNECTING SAID NEEDLE AND LOOP-TAKER FOR MOTION IN TIMED RELATION AS IS REQUIRED FOR THE FORMATION OF LOCK STITCHES, AND MEANS ASSOCIATED WITH SAID LOOP-TAKER FOR REPLENISHING THREAD ON SAID BOBBIN IN PLACE IN SAID LOOP-TAKER DURING MOTION OF SAID NEEDLE AND LOOP-TAKER AS IS REQUIRED FOR THE FORMATION OF LOCK STITCHES THE IMPROVEMENT COMPRISING, A CONTROL MEMBER HAVING AN AT-REST POSITION, MEANS SHIFTABLY SUPPORTING SAID CONTROL MEMBER RELATIVELY TO SAID SEWING MACHINE FRAME FOR MOVEMENT INTO AND OUT OF SAID AT-REST POSITION, MEANS ASSOCIATED WITH SAID CONTROL MEMBER FOR RENDERING SAID THREAD REPLENISHING MEANS INEFFECTIVE WHEN SAID CONTROL MEMBER OCCUPIES SAID AT-REST POSITION AND EFFECTIVE WHILE SAID CONTROL MEMBER IS DISPOSED OUT OF SAID AT-REST POSITION, OPERATOR INFLUENCED MEANS FOR SHIFTING SAID CONTROL MEMBER FROM SAID AT-REST POSITION AND TO ANY SELECTED ONE OF A RANGE OF DISTANCES THEREFROM, AN INDEXING MECHANISM OPERATED BY SAID DRIVE MEANS FOR SAID NEEDLE AND LOOP-TAKER AND OPERATIVE TO RETURN SAID CONTROL MECHANISM TO SAID AT-REST POSITION AT A RATE PROPORTIONAL TO THE SPEED OF OPERATION OF SAID DRIVE MEANS, AND MEANS ASSOCIATED WITH SAID CONTROL MEMBER FOR RENDERING SAID INDEXING MECHANISM EFFECTIVE UPON MOVEMENT OF SAID CONTROL MEMBER OUT OF SAID AT-REST POSITION.