Lock stitch sewing machines

Claim 1

IN A LOCK STITCH SEWING MACHINE HAVING A FRAME, AN ENDWISE RECIPROCATORY NEEDLE BAR, A LOOP TAKER HAVING A BOBBIN JOURNALED THEREIN AND MEANS INCLUDING A SHAFT ROTATABLE IN SAID FRAME FOR OPERATIVELY CONNECTING SAID NEEDLE BAR AND SAID LOOP TAKER FOR MOVEMENT IN TIMED RELATION AS IS REQUIRED FOR THE FORMATION OF LOCK STITCHES, MEANS FOR ACTUATING SAID NEEDLE BAR AND LOOP TAKER CONNECTING MEANS, MECHANISM FOR REPLENISHING THREAD ON SAID BOBBIN IN PLACE IN SAID LOOP TAKER DURING ACTUATION OF SAID NEEDLE BAR AND LOOP TAKER CONNECTING MEANS, CONTROL MECHANISM CARRIED BY SAID SEWING MACHINE FOR RENDERING SAID THREAD REPLENISHING MECHANISM EFFECTIVE AND INEFFECTIVE, A RELEASABLE DRIVING CONNECTION BETWEEN SAID ROTATABLE SHAFT AND SAID NEEDLE BAR DRIVING CRANK MEANS INCLUDING A LATCH LEVER PIVOTALLY SUPPORTED ON SAID CRANK MEANS AND FORMED WITH A DETENT BIASED INTO AND OUT OF INTERLOCKING RELATION WITH A RECESS FORMED IN SAID SHAFT, A RELEASE MEMBER SHIFTABLY SUPPORTED ON SAID SEWING MACHINE FRAME, AND MEANS OPERATIVELY CONNECTED WITH THE CONTROL MECHANISM FOR SAID BOBBIN THREAD REPLENISHING MECHANISM FOR SHIFTING SAID RELEASE MEMBER INTO THE PATH OF SAID LATCH LEVER TO EFFECT MOVEMENT OF SAID LATCH LEVER DETENT OUT OF INTERLOCKING RELATION WITH SAID SHAFT RECESS WHEN SAID BOBBIN THREAD REPLENISHING MECHANISM IS RENDERED EFFECTIVE.