Electro-mechanical brakes especially for machine tools

Claim 1

AN ELECTROMAGNETIC BRAKE COMPRISING, IN COMBINATION: (A) BRAKE DISC MEANS; (B) A PLURALITY OF BRAKE SHOES; (C) A PLURALITY OF BRAKE LEVERS, SAID BRAKE SHOES BEING RESPECTIVELY MOUNTED ON SAID BRAKE LEVERS; (D) SPRING MEANS PERMANENTLY URGING SAID BRAKE SHOES INTO BRAKING ENGAGEMENT WITH SAID BRAKE DISC MEANS; (E) AN ELECTRIC MOTOR ENERGIZABLE FOR ROTATION IN TWO OPPOSITE DIRECTIONS; (F) MOTION TRANSMITTING MEANS INTERPOSED BETWEEN SAID ELECTRIC MOTOR AND SAID BRAKE LEVERS FOR RESPECTIVELY MOVING SAID BRAKE SHOES TOWARD AND AWAY FROM SAID BRAKE DISC MEANS WHEN SAID MOTOR ROTATES IN SAID DIRECTIONS, SAID MOTION TRANSMITTING MEANS INCLUDING (1) SELF-HOLDING GEAR MEANS INCLUDING A WORM SECURED TO SAID MOTOR FOR ROTATION THEREBY, AND A WORM WHEEL ENGAGING SAID WORM, AND (2) AN ELECTROMAGNETIC CLUTCH INTERPOSED BETWEEN SAID WORM WHEEL AND SAID BRAKE LEVERS, SAID CLUTCH INCLUDING A SPRING FOR NORMALLY HOLDING SAID CLUTCH IN A DISENGAGED CONDITION, AND A MAGNET COIL ENERGIZABLE FOR ENGAGING SAID CLUTCH AGAINST THE FORCE OF SAID SPRING; (G) A TIME DELAY CIRCUIT SHUNTED ACROSS SAID MAGNET COIL AND INCLUDING RECTIFIER MEANS, THE DECAY OF THE MAGNETIC FIELD OF SAID MAGNET COIL BEING DELAYED BY SAID SHUNTED CIRCUIT WHEN SAID COIL IS DENERGIZED; (H) A CURRENT SUPPLY CIRCUIT FOR SAID MOTOR; (I) CAM MEANS MOVABLE RESPONSIVE TO SAID MOVEMENTS OF SAID BRAKE LEVERS; AND (J) CAM ACTUATED SWITCH MEANS OPERATIVELY CONNECTED TO SAID CAM MEANS FOR INTERRUPTING SAID CURRENT SUPPLY CIRCUIT WHEN THE BRAKE SHOES HAVE BEEN MOVED OUT OF SAID ENGAGEMENT AND WHEN THE BRAKE SHOES HAVE BEEN MOVED INTO SAID ENGAGEMENT, AND (K) A CONTROL SWITCH HAVING TWO CONTACTS RESPECTIVELY ARRANGED IN SAID CURRENT SUPPLY CIRCUIT OF SAID MOTOR AND IN CIRCUIT WITH SAID COIL.