A proximity sensor comprises a reference inductor, a first set of sensor inductors, a first set of comparators, each comparator of the first set of comparators corresponding to one of the sensor inductors of the first set of sensor inductors, and an alternating current voltage source to output a sinusoidal voltage to the reference inductor and each of the sensor inductors. Each comparator of the first set of comparators receives a voltage across the reference inductor as a reference voltage and each comparator of the first set of comparators receives a voltage across a corresponding sensor inductor as an input voltage.

One inductive sensor is configured to maintain a fixed frequency in a resonant circuit. One apparatus includes an inductance-to-digital converter (LDC). The LDC includes a digital filter to measure an inductance change of a sensor and convert the inductance change to a digital value. The LDC further includes a digital control loop to maintain a fixed frequency in the sensor. The sensor forms an oscillator in the digital control loop. An output of the digital control loop is representative of the inductance change of the sensor.

A method is provided for sensing proximity of a target. The method includes sensing inductance associated with a magnetic field, wherein the inductance is affected by the target when the target is proximate the magnetic field. The method further includes providing the sensed inductance for processing. The processing includes determining an inductance value from at least the sensed inductance and estimating a parameter of a gap between a location of sensing the inductance and the target as a function of the inductance value and application of a nonlinear model of a relationship between the gap and inductance.

A proximity sensor for the inductive detection of objects, including a housing with a front cap, a processing and receiving unit, comprising a printed circuit board, which is configured to connect to an external control and evaluation unit, and a coil carrier, on which at least one primary coil and at least one first secondary coil are arranged circumferentially wound and spaced apart in an axial direction of an axis extending axially through the housing, wherein the first secondary coil lies closer, in the axial direction, to the end face than the primary coil, wherein a second secondary coil is arranged on the coil carrier, wherein the primary coil is arranged between the first and second secondary coils, wherein a metallic shielding element is arranged in an axial area surrounding the second secondary coil and is not arranged in an axial area surrounding the first secondary coil.

A system may include a sensor configured to output a sensor signal indicative of a distance between the sensor and a mechanical member associated with the sensor, a measurement circuit communicatively coupled to the sensor and configured to determine a physical force interaction with the mechanical member based on the sensor signal, and a compensator configured to monitor the sensor signal and to apply a compensation factor to the sensor signal to compensate for changes to properties of the sensor based on at least one of changes in a distance between the sensor and the mechanical member and changes in a temperature associated with the sensor.

Traffic control systems and methods to improve safety are disclosed. The systems, in some example aspects, include a first magnetic field generator mounted over an aisle for generating a first zone magnetic field defining a first zone. The methods, in some example aspects, include generating a first zone magnetic field defining a first zone by a first magnetic field generator mounted over an aisle. Other aspects include generating, and/or including a controller to generate, control signals to reduce the speed of a vehicle, and/or reduce the size of a danger zone.

One inductive sensor is configured to maintain a fixed frequency in a resonant circuit. One apparatus includes an inductance-to-digital converter (LDC). The LDC includes a digital filter to measure an inductance change of a sensor and convert the inductance change to a digital value. The LDC further includes a digital control loop to maintain a fixed frequency in the sensor. The sensor forms an oscillator in the digital control loop. An output of the digital control loop is representative of the inductance change of the sensor.

Mechanized area controller systems and methods for coordinating the movement of workers and vehicles to improve safety are disclosed. Some embodiments of the methods include generating a magnetic field defining a first zone and detecting a response signal from a first device. Other method embodiments also include detecting a response signal from a second device and generating a danger signal when the first and second devices are both within the first zone. Some system embodiments include a magnetic field generator for defining a first zone and a first device configured to detect the first zone magnetic field and generate a first device response signal. Other system embodiments also include a second device configured to detect the first zone magnetic field and generate a second device response signal and a first controller configured to generate a danger signal when the first and second devices are both within the first zone.

A devise that will increase an inductive proximity sensor's detection distance and detection position. The devise uses a housing in combination with a sensor and axially magnetized magnet and a target magnet to achieve the increased detection distance and position. The devise can be defined as universal because it allows different manufacturers and sizes of sensors to be used and calibrated. A treaded end section of the devise allows connection of standard conduit fittings.

A machinery brake of an elevator includes a frame part including an electromagnet, an armature part, an inductive proximity sensor indirectly mounted to one of the following: the frame part, the armature part, and a target mounted to another of the following: the frame part, armature part. The machinery brake further includes, for establishing the indirect mounting: a temperature change compensation device mounted between the inductive proximity sensor and one of the following: the frame part, the armature part. Some aspects relate to a method for compensating a change in switching point of an inductive proximity sensor.