Needle positioning mechanism for sewing machines

Claim 1

IN A SEWING MACHINE, INCLUDING A SEWING HEAD HAVING A ROTARY DRIVE SHAFT, A NEEDLE BAR OPERATIVELY CONNECTED TO SAID ROTARY SHAFT FOR RECIPROCATION THEREBY, A MOTOR, A MAIN TRANSMISSION INCLUDING A MAIN DRIVEN SHAFT OPERATIVELY CONNECTED TO SAID ROTARY SHAFT AND MOVABLE MEANS RELEASABLY OPERATIVELY CONNECTING SAID MAIN DRIVEN SHAFT TO SAID MOTOR, THE IMPROVEMENT CONSISTING OF A SECONDARY TRANSMISSION ROTATABLE BY SAID ROTOR AT A LESSER SPEED THAN SAID MAIN TRANSMISSION, SAID SECONDARY TRANSMISSION INCLUDING A SECONDARY DRIVEN SHAFT PARALLEL TO SAID MAIN DRIVEN SHAFT, MEANS INTERCONNECTING SAID DRIVEN SHAFTS FOR ROTATION SIMULTANEOUSLY IN ONE DIRECTION, MEANS RELEASABLY OPERATIVELY CONNECTING SAID SECONDARY DRIVEN SHAFT WITH SAID MOTOR, AND MEANS OPERABLE BY SAID MOVABLE MEANS UPON MOVEMENT THEREOF TO RELEASE SAID MAIN DRIVEN SHAFT FROM SAID MOTOR TO CONNECT SAID SECONDARY DRIVEN SHAFT WITH SAID MOTOR, AND MEANS CONTROLLED BY SAID ROTARY DRIVE SHAFT FOR RELEASING SAID SECONDARY DRIVEN SHAFT FROM SAID MOTOR UPON POSITIONING OF SAID NEEDLE BAR AT A PREDETERMINED POSITION.