Valve systems include at least one component comprising a conductive material and at least one inductance-to-digital converter (LDC) configured to wirelessly sense a position of at least a portion of the conductive material. The valve system is configured to determine at least one force applied to a portion of the valve system based at least partially on the position of the at least a portion of the conductive material. Methods of determining a force associated with a valve system include wirelessly sensing a position of at least a portion of the conductive material with the at least one inductance-to-digital converter (LDC) sensor and determining a force applied to a portion of the valve system based at least partially on the position of the at least a portion of the conductive material.

Remote inductive sensing uses a sensor resonator with a remote sense inductor coupled to a resonator capacitor through a shielded transmission line. The T-line includes a signal line and a shield return line: the sense inductor is connected at a T-line sensing end between the signal line and the shield return line, and the resonator capacitor is connected at a T-line terminal end to at least the signal line. An inductance-to-data converter (IDC) is connected at the T-line terminal end to the signal line and shield return line (set to a common mode voltage). In operation, the IDC drives oscillation signals over the signal line to the sensor resonator to sustain a resonance state, with the sense inductor projecting a magnetic sensing field, and converts changes in oscillation drive signals, representing changes in resonance state resulting from a sensed condition, into sensor data corresponding to the sensed condition.

The invention relates to a circuit for detecting a variation in inductance of the magnetic circuit of an inductive displacement sensor, wherein the detector circuit comprises:

a first flip flop arranged to supply a first signal comprising a voltage pulse of necessary and sufficient duration to charge the coil to a threshold current, wherein the first signal is applied to a first terminal of the coil

a pulse generator configured to supply a reference signal comprising a reference pulse

a clock signal generator arranged to trigger the charge pulse and the reference pulse periodically and simultaneously

a second flip flop arranged to generate an output signal taking the status of the first signal on the trailing edge of the reference pulse.

A system may include a resistive-inductive-capacitive sensor configured to sense a physical quantity, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to measure one or more resonance parameters associated with the resistive-inductive-capacitive sensor and indicative of the physical quantity and, in order to maximize dynamic range in determining the physical quantity from the one or more resonance parameters, dynamically modify, across the dynamic range, either of reliance on the one or more resonance parameters in determining the physical quantity or one or more resonance properties of the resistive-inductive-capacitive sensor.

One embodiment relates to a door operator including an operator body including a rotatable pinion, an arm connected to the pinion, an inductive sensor mounted adjacent the arm, and a controller in communication with the inductive sensor. The inductive sensor includes an inductor comprising a plurality of nested coils, and each of the coils is curved about the pinion. The controller is configured to provide the inductive sensor with a varying power signal, and the inductive sensor is configured to inductively link the inductor to the arm in response to the varying power signal. The inductive sensor has a characteristic which varies in response to the rotational position of the arm when the inductor is inductively linked with the arm. The controller is further configured receive information relating to the characteristic, and to determine the rotational position of the arm based upon the received information.

A stroke sensor system includes a tubular vehicle-body-side member, a tubular vehicle-wheel-side member, and a displacement obtainer. The tubular vehicle-body-side member is disposed at a vehicle body side. The tubular vehicle-wheel-side member is coupled to the vehicle-body-side member on a vehicle wheel side and movable in an axial direction of the vehicle-body-side member relative to the vehicle-body-side member. At least one of the members is a conductor. Another one of the members includes a coil. The displacement obtainer includes a capacitor electrically coupled to the coil and constituting an LC oscillation circuit that outputs an oscillation waveform when the members move relative to each other. The displacement obtainer digitizes the oscillation waveform to obtain a reshaped waveform, divides a frequency of the reshaped waveform by a frequency division ratio to obtain a frequency-divided waveform, and uses the frequency-divided waveform to obtain a displacement by which the members move relative to each other.

A resolver that ensures improvement in a detection sensitivity is provided. The resolver according to the present disclosure includes a rotor and a stator arranged to surround an outer peripheral surface of the rotor. The rotor includes a rotor core, the stator includes a stator core and a coil, the stator core includes a plurality of teeth disposed at intervals along a circumferential direction, the plurality of teeth project toward the outer peripheral surface side of the rotor, and the coil is wound around the plurality of teeth. A gap permeance between the rotor and the stator varies in association with a rotation around a rotation axis of the rotor. The rotor further includes a porous machinable film containing a magnetic metal, and the porous machinable film is disposed on a projecting portion on an outer peripheral surface of the rotor core.

An inductive type position encoder includes a scale, a detector portion and a signal processor. The scale includes a periodic pattern of signal modulating elements (SME) arranged along a measuring axis with a spatial wavelength W1. The SME in the pattern comprise similar conductive plates or loops. The detector portion comprises sensing elements and a field generating coil that generates a changing magnetic flux. The sensing elements may comprise conductive loop portions arranged along the measuring axis and configured to provide detector signals which respond to a local effect on the changing magnetic flux provided by adjacent SME's. In various implementations, SMEs having an average dimension DSME along the measuring axis direction that is at least 0.55*W1 and at most 0.8*W1 are combined with sensing elements having an average dimension along the measuring axis direction that is at least 0.285*W1 and at most 0.315*W1, which improves detector signal accuracy.

A trigger assembly, for use with a power tool having an electric motor, includes a trigger, a conductor coupled for movement with the trigger, and a printed circuit board. The printed circuit board has an inductive sensor thereon responsive to relative movement between the conductor and the inductive sensor caused by movement of the trigger. An output of the inductive sensor is used to activate the electric motor.

Provided is a movement distance measurement apparatus for confirming the operating state of a power transmission device for automobiles, which has removed the effect of temperature, and the movement distance measurement apparatus for confirming the operating state of a power transmission device for automobiles, which has removed the effect of temperature, is configured to measure the movement distance T of the detection target object 20 using a resonance circuit including the sensing coil by using changes in the resonance frequency of the resonance circuit and changes in the output voltage of the resonance circuit according to changes in the distance between the detection target object 20 and the sensing coil, and to be provided with a diode voltage detection unit that separately detects diode voltage included in the output value of the resonance circuit not to be affected by temperature change by removing the diode voltage.