Apparatus for proportionally converting a rotational angle into a phase angle of an alternating voltage

Claim 1

A SHAFT-POSITION INDICATING DEVICE COMPRISING ROTOR AND STATOR ELEMENTS CLOSELY OPPOSED, ONE OF SAID ELEMENTS HAVING FIRST AND SECOND PAIRS OF ELECTRODES, ONE PAIR BEING RADIALLY OUTWARD OF THE OTHER, THE MEMBERS OF EACH PAIR OF ELECTRODES BEING IN THE FORM OF COPLANAR CONDUCTING AREAS SEPARATED BY STRAIGHT INSULATING LINES LYING ON RADII OF THE SHAFT WITH ALTERNATE AREAS INTERCONNECTED TO FORM MESHED ELECTRODE PAIRS, INSULATING LINES ON ONE PAIR BEING OUT OF ALIGNMENT WITH INSULATING LINES ON THE OTHER, AND THE OTHER OF SAID ELEMENTS COMPRISING CONDUCTING AREAS SEPARATED BY STRAIGHT INSULATING LINES LYING ON RADII OF THE SHAFT, EACH SUCH CONDUCTING AREA ON SAID OTHER ELEMENT BEING OF A LENGTH TO FACE BOTH PAIRS OF ELECTRODES ON THE FIRST ELEMENT, MEANS TO IMPRESS ALTERNATING VOLTAGES OF CONSTANT PHASE DIFFERENCE ON THE RESPECTIVE PAIRS OF ELECTRODES OF THE FIRST ELEMENT, SO THAT THE PHASE OF THE VOLTAGE INDUCED IN THE AREAS OF SAID OTHER ELEMENT VARIES IN ACCORDANCE WITH THE SHAFT ROTATION, AND MEANS TO INDICATE THE PHASE OF THE VOLTAGE CAPACITATIVELY INDUCED IN SAID OTHER ELEMENT.