Electro-magnetic rotation measuring apparatus

Claim 1

APPARATUS COMPRISING A ROTARY DEVICE MOUNTED FOR ROTATION WITH RESPECT TO A STATIONARY SUPPORT MEMBER, THE SAID ROTARY DEVICE INCLUDING A PART WHICH IS LIABLE TO RECIPROCATE WITH RESPECT TO THE REMAINDER OF THE ROTARY DEVICE DURING ROTATION OF THE ROTARY DEVICE, AND MEANS FOR MEASURING THE FREQUENCY OF RECIPROCATION OF THE SAID RECIPROCATING PART OF THE ROTARY DEVICE, SAID MEASURING MEANS COMPRISING SIGNAL GENERATING MEANS INCLUDING A FIRST PART MOUNTED ON THE RECIPROCATING PART OF THE ROTARY DEVICE AND A SECOND PART COMPRISING AN ELECTRICAL CONDUCTOR MOUNTED ON THE STATIONARY SUPPORT MEMBER AND FORMED BY A PLURALITY OF REGULARLY SPACED BUT INTERCONNECTED MUTUALLY PARALLEL BAR ELEMENTS FORMING AN ANNULUS CO-AXIAL WITH THE ROTARY DEVICE, THE BARS BEING SO POSITIONED ON THE SUPPORT MEMBER THAT ROTATION OF THE ROTARY DEVICE CARRIES THE FIRST PART ACROSS EACH OF THE BAR ELEMENTS IN TURN WHEN NO RECIPROCATION OF THE RECIPROCATING PART IS OCCURRING, WHEREBY A CARRIER ELECTRICAL SIGNAL IS GIVEN BY THE CONDUCTOR AT A FIXED FREQUENCY WHEN NO RECIPROCATION OF THE RECIPROCATING PART IS OCCURRING, THE SAID CARRIER SIGNAL DURING ACTUAL RECIPROCATION OF THE RECIPROCATING PART BEING MODIFIED, WHICH MODIFICATION IS INDICATIVE OF THE FREQUENCY AND VELOCITY OF RECIPROCATION OF THE RECIPROCATING PART WITH RESPECT TO THE REMAINDER OF THE ROTARY DEVICE.