Inductive sensor

About: Inductive sensor is a research topic. Over the lifetime, 2282 publications have been published within this topic receiving 21984 citations.

Capacitive proximity sensor and proximity sensing method

Abstract: A capacitive proximity sensor ( 100 ) comprises a sensor unit ( 10 ) and a sense circuit unit ( 20 ). The sensor unit ( 10 ) includes a sensor electrode ( 11 ), a shield electrode ( 12 ) and an auxiliary electrode ( 13 ). The sensor electrode ( 11 ) is connected to a C-V conversion circuit ( 21 ) and the shield electrode ( 12 ) is connected to a shield drive circuit ( 24 ). The auxiliary electrode ( 13 ) is connected via a change-over switch ( 30 ) to the C-V conversion circuit ( 21 ) or the shield drive circuit ( 24 ). The capacitance values (C 1 , C 2 ) switched by the change-over switch ( 30 ) and detected at the C-V conversion circuit ( 21 ) are compared to arbitrarily set a range of a sense region on the sensor electrode ( 11 ).

System and method for measuring variable impedance elements in a wireless sensor

Abstract: A wireless remote sensor (110) that is powered by an inductive transmitter (112) and is configured to produce an oscillating wave that varies based on one or more sensed parameters. The oscillating wave is communicated to the inductive transmitter (112) by reflected impedance, where it can be detected to determine the sensed value(s). In another aspect, the present invention provides a wireless remote sensor with a Wheatstone bridge arrangement having an internal resonant circuit to produce an electromagnetic field indicative of the sensed value. In a third aspect, the present invention provides a wireless remote sensor with optical feedback from a reference circuit and a sensor circuit. In a fourth aspect, the present invention provides a wireless remote temperature sensor having coils printed on a material with a high coefficient of thermal expansion so that the size and/or shape of the coils varies as the temperature increases or decreases.

Sensor unit with staggered actuation faces

Abstract: An inductive sensor for detecting the position of a vehicle seat or for a gate shifting unit of an automatic transmission is described. The inductive sensor unit has a plurality of sensor coils that are disposed in planar fashion on a printed circuit board A conductive actuation element is guided, spaced apart, in a path over the sensor coils and an electrical evaluation circuit detects changes in inductance of the sensor coils in accordance with the path position of the actuation element and converts the changes into electrical signals corresponding to seat position signals on gear shifting signals. The actuation element is guided along the sensor coils with conductive bottom faces that are staggered in the direction of the path.

Capacitive/Inductive Proximity Detection for Wi-Fi Protection

Abstract: A combination of capacitive, mutual capacitive, and inductive proximity and touch sensing is used to detect the presence and nature of nearby objects to a wireless device. When the proximity of metal or a user is sensed the output power of a Wi-Fi module in the device is reduced so as to prevent harm to the user and/or the Wi-Fi transmitter amplifier circuits. Inductive sensors located at the four corners of the wireless device are used to detect metal, and capacitive sensors are used to detect a capacitance change or shift due to the presence of a user's hand, body or metal. In addition, the capacitive sensors may be located at the four corners of the device and can measure changes in the mutual capacitance coupling between these capacitive sensors.