Patent ID: 11898887
Assignee: MICROCHIP TECHNOLOGY INCORPORATED
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 9:
10. A rotational-position sensor, comprising:
a sense coil defining a continuous path for electrical current to flow between a first location and a second location, the continuous path comprising:
a first sense coil portion defined by a generally clockwise path for the electrical current to flow around an axis of rotation for a target;
a second sense coil portion defined by a generally counter-clockwise path for the electrical current to flow around the axis of rotation;
the first sense coil portion and the second sense coil portion together defining at least a first lobe and a second lobe, the second lobe adjacent and meeting with the first lobe at an inter-lobe region;
the inter-lobe region having a radial-direction-reversal region at which one of the first sense coil portion or the second sense coil portion defined as one of the generally clockwise path or the generally counter-clockwise path changes from being a generally outward path along a portion of the first lobe for the electrical current to flow away from the axis of rotation to a generally inward path along a portion of the second lobe for the electrical current to flow toward the axis of rotation in the same one of the generally clockwise path or the generally counter-clockwise path;

an oscillator coil arranged around the sense coil, wherein when an excitation signal is carried by the oscillator coil, a magnetic coupling is formed between a sense signal carried at the sense coil and the excitation signal;
the target arranged to rotate about the axis of rotation perpendicular to a plane of the sense coil and to influence a degree of magnetic coupling between the excitation signal and the sense signal, wherein the sense signal is modulated by a change in the degree of magnetic coupling responsive to the rotation of the target to generate a modulated sense signal; and
an integrated circuit to generate an output signal responsive to the modulated sense signal,
wherein respective geometries of the first sense coil portion and the second sense coil portion are such that the output signal is characterized by a waveform that, in response to a full rotation of the target in a clockwise direction, generally decreases, plateaus and then generally increases, and in response to a full rotation of the target in a counter-clockwise direction, generally decreases, plateaus, and then generally increases.