A detector (10) for detecting electrically conductive material is provided. The detector (10) comprises at least one transmitter (11) having a transmitter coil (12) and a supply source (13), a receiver (14) having a receiver coil (15), and an evaluation unit (16), wherein the transmitter coil (12) is connected to the supply source (13), the supply source (13) is configured to provide an alternating voltage or an alternating current when in use, the receiver (14) is designed as a resonant-circuit-free receiver, the receiver (14) is connected to the evaluation unit (16), and the evaluation unit (16) is configured to detect a signal induced in the receiver coil (15).

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.

To provide an elevator car position detection sensor capable of suppressing erroneous detection of presence or absence of a plate. The elevator car position detection sensor includes a first coil provided to one of an elevator car and a hoistway and configured to output an excitation magnetic field to a plate provided to the other of the elevator car and the hoistway; a second coil provided on an opposite side of the first coil relative to the plate; a shield wall configured to shield an end portion of the plate located closer to one of the car and the hoistway; and a determination circuit configured to determine a phase of an alternating-current voltage corresponding to a frequency of the excitation magnetic field output from the first coil at an alternating-current voltage generated across the second coil.

Techniques are disclosed relating to sensing an object using an inductive proximity sensor. In an embodiment, an apparatus includes a transmission coil having turns formed on a first circuit board and including a first primary winding having a first winding direction. The apparatus further includes a first sensor coil having turns formed on a second circuit board and including a second primary winding having a second winding direction and a second sensor coil having turns formed on a third circuit board and including a third primary winding having a third winding direction opposite to the second winding direction. The coils are spaced apart from one another in a common axial direction and at least one of the coils includes a compensation winding having at least one turn, where the compensation winding is arranged radially outside of, and has a winding direction opposite to, the same coil's primary winding.

An apparatus for identifying when an individual is in proximity to an object having a length has a sensor portion having a wire loop through which electric current runs and creates an electromagnetic field that emanates about the wire loop. The wire loop extending along at least a third of the length of the object. The apparatus has a personal alarm device that is worn by the individual which detects the presence of the magnetic field emanating from the wire loop when the personal alarm device is in the magnetic field and produces a signal indicating the personal alarm device is within the magnetic field. Alternatively, the sensor portion extends from a contiguous boundary up to 500 meters, where the boundary has a geometry that is linear or meandering. A head piece for an individual's head. A method for identifying when an individual is in proximity to an object. A field extension module. A proximity device.

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.

Disclosed is a device for detecting intention to lock or unlock a door of a motor vehicle, the device including at least a first inductive sensor, including a first target, an oscillating circuit including a coil, a unit measuring a resonant frequency of the circuit, and a printed circuit. The device includes a second inductive sensor including: a second target in the form of a loop, such that a first end of the loop is connected to a fixed potential, and a second end of the loop is connected to a switch having two states, in a first state, the second end of the loop is connected to the fixed potential, in a second state, the second end of the loop is connected to a floating potential; and a controller for the switch. The coil of the first inductive sensor is common to the second inductive sensor.

An explosion-proof electronic system. The system comprises a substantially explosion-proof enclosure, a substantially explosion-proof glass window forming a portion of the enclosure, an electrical coil located within the enclosure, an electrical excitation circuit located within the enclosure and connected to the electrical coil, where the excitation circuit is configured to cause the electrical coil to establish a magnetic field that extends through the explosion-proof glass window, and a processor located within the enclosure and coupled to the electrical excitation circuit. The processor is configured to monitor the electrical excitation circuit, determine an electrical inductance of the electrical coil based on monitoring the electrical excitation circuit, identify a fluctuation of the electrical inductance that exceeds a predetermined threshold as a control input, and transmit an output in response to the control input, whereby a human operator can provide the control input by bringing a finger proximate to the explosion-proof glass window.

Disclosed is a device for detecting intention to lock or unlock a door of a motor vehicle, the device including at least a first inductive sensor, including a first target, an oscillating circuit including a coil, a unit measuring a resonant frequency of the circuit, and a printed circuit. The device includes a second inductive sensor including: a second target in the form of a loop, such that a first end of the loop is connected to a fixed potential, and a second end of the loop is connected to a switch having two states, in a first state, the second end of the loop is connected to the fixed potential, in a second state, the second end of the loop is connected to a floating potential; and a controller for the switch. The coil of the first inductive sensor is common to the second inductive sensor.

A detector (10) for detecting electrically conductive material is provided. The detector (10) comprises at least one transmitter (11) having a transmitter coil (12) and a supply source (13), a receiver (14) having a receiver coil (15), and an evaluation unit (16), wherein the transmitter coil (12) is connected to the supply source (13), the supply source (13) is configured to provide an alternating voltage or an alternating current when in use, the receiver (14) is designed as a resonant-circuit-free receiver, the receiver (14) is connected to the evaluation unit (16), and the evaluation unit (16) is configured to detect a signal induced in the receiver coil (15).