Semiconductor force measuring device

Claim 1

A TORQUE METER FOR ATTACHMENT OT A ROTATABLE SHAFT COMPRISING A DEVICE INCLUDING A SEMICONDUCTOR WAFER HAVING A RECTIFYING JUNCTION THEREIN AND HAVING A NEGATIVE RESISTANCE REGION IN ITS VI CHARACTERISTIC; MEANS FOR BIASING SAID DEVICE SUCH THAT ROTATION OF SAID SHAFT WILL CAUSE DEFORMATION OF SAID WAFER TO CAUSE CHANGE OF THE OPERATING POINT ON SAID VI CHARACTERISTIC AND THEREBY ENABLE CHANGE OF THE SWITCHING FREQUENCY OF SAID DEVICE; A TANK CIRCUIT INCLUDING A REACTIVE MEANS AND A RESISTIVE MEANS CONNECTED TO SAID DEVICE TO FORM AN OSCILLATOR GENERATOR WHOSE FREQUENCY OF OSCILLATION IS INDICATIVE OF THE TORQUE ESTABLISHED BY SAID ROTATABLE SHAFT; A PHOTO CELL ATTACHED TO SAID SHAFT FOR PROVIDING POWER TO SAID DEVICE, AND BEING RESPONSIVE TO LIGHT FROM A SOURCE EXTERNAL TO SAID SHAFT ONCE PER REVOLUTION THEREOF; MEANS FOR TRANSMITTING A SIGNAL WHICH COMBINES THE OUTPUT SIGNALS OF SAID OSCILLATOR GENERATOR AND SIGNALS FROM SAID PHOTOCELL; AND MEANS EXTERNAL TO SAID SHAFT FOR RECEIVING SAID COMBINATION SIGNAL AND FOR COMPUTING THE POWER OUTPUT OF SAID SHAFT.