Apparatus for stopping a sewing machine with its needle in pre-determined position

Claim 1

A SEWING MACHINE INCLUDING A MOTOR DRIVE, SHAFT, A DRIVEN SHAFT, AND AN ELECTROMAGNETIC CLUTCH COUPLING THE AFOREMENTIONED SHAFTS TO EACH OTHER, AN AXIALLY RECIPROCABLE NEEDLE OPERATIVELY ASSOCIATED WITH SAID DRIVEN SHAFT AND RECIPROCATINGLY DRIVEN THEREBY BETWEEN THE TOP AND BOTTOM AXIAL POSITIONS, AN ELECTROMAGNETIC BRAKE OPERABLE TO EXERT A BRAKING ACTION UPON SAID DRIVEN SHAFT, A GENERATOR DRIVINGLY CONNECTED TO SAID DRIVEN SHAFT AND PROVIDING A VOLTAGE OUTPUT PROPORTIONAL TO THE SPEED OF SAID DRIVEN SHAFT, A STOPPING MEANS FOR STOPPING SAID DRIVEN SHAFT IN CORRESPONDENCE TO SAID NEEDLE BEING AT ONE OF VARIOUS PRE-ESTABLISHED AXIAL POSITIONS, SAID STOPPING MEANS COMPRISING RESPECTIVE ENERGIZING CIRCUITS FOR SAID BRAKE AND SAID CLUTCH, SAID CIRCUITS INCLUDING A ZENER DIODE AND THE VOLTAGE OUTPUT OF SAID GENERATOR BEING IMPRESSABLE UPON SAID BRAKE CIRCUIT THROUGH SAID ZENER DIODE, SAID GENERATOR PROVIDING A VOLTAGE OUTPUT IN OPPOSITION TO THE NORMAL BIAS OF SAID DIODE, AND SAID GENERATOR OUTPUT BEING IMPRESSABLE UPON SAID CLUTCH CIRCUIT WITH SAID ZENER DIODE SERVING TO LIMIT THE SAID VOLTAGE OUTPUT TO SAID CLUTCH TO A VALUE NO GREATER THAN THE DIODE BREAKDOWN VOLTAGE, A FOLLOWER MEANS HAVING RESPECTIVE POSITIONS CORRESPONDING TO RESPECTIVE POSITIONS OF SAID NEEDLE, AND SWITCH MEANS OPERATIVE TO SIMULTANEOUSLY EXCITE AND DE-EXCITE SAID BRAKE AND CLUTCH, RESPECTIVELY, SAID SWITCH MEANS BEING OPERATIVELY ASSOCIATED WITH SAID FOLLOWER MEANS, SAID FOLLOWER MEANS BEING CORRELATED TO ACTUATE SAID SWITCH MEANS IN CORRESPONDENCE TO PARTICULAR POSITIONS OF SAID NEEDLE.