Positive stop mechanism

Claim 1

A ROTATABLY MOUNTED SHAFT MEMBER HAVING AN END THEREOF EXTENDED INTO A FIXED HOUSING, A DRIVE MEMBER ROTATABLY MOUNTED ON SAID SHAFT END, SAID DRIVE MEMBER HAVING A PINION FORMING PORTION AND A CUP-LIKE FLANGE FORMING PORTION, A RECIPROCABLY MOUNTED RACK ENGAGING THE PINION PORTION OF SAID DRIVE MEMBER, POWER MEANS FOR RECIPROCATING SAID RACK, A PLATE CLUTCH ASSEMBLY MOUNTED ON THE EXTENDED SHAFT END ADJACENT SAID DRIVE MEMBER, WHICH CLUTCH ASSEMBLY COMPRISES COOPERATING INTERLEAVED CLUTCH PLATES MOUNTED ON SAID SHAFT END AND IN THE CUPLIKE PORTION OF SAID DRIVE MEMBER, A BRAKE ASSEMBLY MOUNTED ON SAID SHAFT END IN AXIALLY SPACED RELATION TO SAID CLUTCH ASSEMBLY WHICH BRAKE ASSEMBLY COMPRISES COOPERATING INTERLEAVED ANNULAR BRAKE PLATES MOUNTED ON SAID SHAFT END AND SAID FIXED HOUSING, RESPECTIVELY, A PAIR OF SLEEVE-LIKE ACTUATOR MEMBERS MOUNTED IN AXIALLY MOVABLE RELATION ON SAID SHAFT END BETWEEN SAID CLUTCH AND BRAKE ASSEMBLIES, SAID ACTUATOR MEMBERS HAVING PRESSURE APPLYING FLANGES AT THE OPPOSITELY DISPOSED ENDS THEREOF, PERIPHERALLY SPACED COMPRESSION SPRINGS SUPPORTED ON SAID ACTUATOR MEMBERS BETWEEN SAID PRESSURE APPLYING FLANGES WHICH URGE SAID FLANGES INTO PRESSURE ENGAGEMENT WITH THE CLUTCH PLATES AND THE BRAKE PLATES, RESPECTIVELY, IN THE CENTRAL POSITION OF SAID ACTUATOR MEMBERS, SAID SHAFT END HAVING AN AXIAL BORE, A ROD MEMBER MOUNTED IN SAID BORE FOR AXIAL RECIPROCATING MOVEMENT, POWER MEANS FOR RECIPROCATING SAID ROD MEMBER, A RADIALLY AND AXIALLY EXTENDING SLOT IN SAID SHAFT END AND COMMUNICATING WITH SAID BORE, A RELATIVELY FLAT PLATE-LIKE RECTANGULAR KEY MEMBER SECURED ON SAID ROD MEMBER AND MOVABLE IN AN AXIAL DIRECTION IN SAID SLOT WITH THE EDGES THEREOF PROJECTING AT OPPOSITE SIDES OF SAID SHAFT END, A NOTCH IN EACH OF SAID PROJECTING KEY EDGES, SAID ACTUATOR MEMBERS HAVING PORTIONS EXTENDING INTO SAID NOTCHES SO THAT SAID ACTUATOR MEMBERS MOVE AXIALLY ON SAID SHAFT END IN RESPONSE TO MOVEMENTS OF SAID ROD MEMBER, AND MANUALLY ACTUATED OPERATING MECHANISM CONNECTED TO THE POWER MEANS FOR SAID RACK AND SAID ROD MEMBER WHEREBY WHEN SAID RACK MEMBER IS OPERATED SAID CLUTCH AND BRAKE ASSEMBLIES ARE ACTUATED AUTOMATICALLY TO FIRST ROTATE THE SHAFT MEMBER AND THEREAFTER TO HOLD THE SHAFT MEMBER IN A STATIONARY CONDITION AFTER IT HAS COME TO A POSITIVE STOP.