Thread-cutting apparatus

Claim 1

A THREAD-CUTTING APPARATUS HAVING A ROTATABLE DRIVING PART AND A ROTATABLE DRIVE PART, A FIRST COUPLING MEMBERS FOR CONNECTING SAID PARTS, WHEN SAID FIRST COUPLING MEMBERS ARE ENGAGED, TO ROTATE SAID DRIVEN PART IN DIRECT DRIVE IN THE SAME DIRECTION AS SAID DRIVING PART, AND SECOND COUPLING MEMBERS FOR CONNECTING SAID PARTS, WHEN SAID SECOND COUPLING MEMBERS ARE ENGAGED, TO ROTATE SAID DRIVEN PART BY INDIRECT DRIVE IN THE REVERSE DIRECTION TO SAID DRIVING PART, FIRST SPRING MEANS INTERPOSED BETWEEN SAID DRIVING PART AND SAID FIRST COUPLING MEMBERS AND CONSTANTLY URGING SAID FIRST COUPLING MEMBERS INTO ENGAGEMENT TO TRANSMIT TORQUE FROM SAID DRIVING PART TO SAID DRIVEN PART DURING DIRECT DRIVE SO LONG AS THE TORQUE DOES NOT EXCEED A PREDETERMINED VALUE, SAID FIRST COUPLING MEMBERS BEING ADAPTED TO DISENGAGE TO INTERRUPT THE DIRECT DRIVE BETWEEN SAID TWO PARTS WHEN SAID TORQUE EXCEEDS THE PREDETERMINED VALVE, SAID SIAD SECOND COUPLING MEMBERS COMPRISING ROTATABLE BEARING MEMBERS, A STATIONARY RETAINER FOR SAID BEARING MEMBERS, AND OUTER AND INNER RACEWAYS THEREFOR, SAID OUTER RACEWAY BEING CONNECTED TO THE DRIVING PART, A REVERSING MEMBER CONNECTED TO THE DRIVEN PART DURING INDIRECT DRIVE THEREOF AND TO WHICH SAID INNER RACEWAY IS CONNECTED, AND SECOND SPRING MEANS EXERTING AXIAL PRESSURE ON SAID RACEWAYS, AND POSITIONED TO COOPERATE WITH SAID FIRST SPRING MEANS TO CAUSE SAID SECOND MEMBERS TO TRANSMIT TORQUE FROM SAID DRIVING PART TO SAID DRIVEN PART TO EFFECT REVERSE DRIVE, WITHOUT INFLUENCE ON DIRECT DRIVE.