A system for sensing a position of a locking bolt of an industrial locking switch includes an inductive circuit, a converter, and a master controller. The inductive circuit includes an inductive coil and a capacitor electrically connected in parallel. The inductive coil is positioned to receive a locking bolt of an industrial locking switch when the locking bolt is transitioned to a lock position. The converter is configured to convert a frequency of a current signal on the inductive circuit to a digital frequency value. The master controller is configured to generate a bolt detection signal in response to determining that the digital frequency value changes by an amount equal to or substantially equal to a defined frequency shift corresponding to a frequency shift induced by the inductive coil in response to presence of the locking bolt within the inductive coil's magnetic field.

A sensor includes a housing and an antenna element. The first wall and the second wall of the housing are facing each other at a distance from each other. The third wall and the fourth wall connect the first wall and the second wall and are facing at a distance from each other and have a larger area than the first wall and the second wall respectively. The housing has an internal space surrounded by the first wall, the second wall, the third wall, and the fourth wall. The antenna element is arranged in the internal space of the housing and receives identification information of an external actuator for detecting opening/closing of a door. The antenna element is arranged at a position, which is closer to the first wall than the second wall and includes a substantially center in a direction connecting the third wall and the fourth wall.

An industrial locking switch includes an inductive sensing circuit that uses a non-contact technique to detect when the switch's locking bolt has transitioned to the lock position. The inductive sensing circuit can comprise an inductive coil, a capacitor, and a converter that converts a frequency of a current signal through the inductive coil to a digital frequency value. A controller detects when the locking bolt has advanced to the lock position by monitoring the digital frequency value for frequency shifts indicative of a disturbance of the induction coil's magnetic field by the locking bolt. To validate operation of the inductive sensing system without requiring actuation of the locking bolt, a diagnostic switch connects a diagnostic capacitor to the inductive circuit to simulate the frequency shift caused by the locking bolt, and the inductive sensing system is validated if the expected frequency shift is detected.

The present invention relates to a safety device for securing a machine having a sensor that is configured to detect the presence of an object in a monitored zone and to output a detection signal when an object is located in the monitored zone and having an evaluation unit that is configured to receive the detection signal from the senor and to generate an output signal in dependence on the detection signal. Provision is made in accordance with the invention that the evaluation unit is adapted furthermore to generate the output signal in dependence on at least one additional criterion.

A non-mechanical-interfacing electronic switch or a mechanical-interfacing electronic switch are controlled to modulate between an active state and an inactive state based on electronic action. The switch includes an aperture defining an opening in a housing, and the opening defines an insertion path. A transmitter transmits a signal to a receiver along a signal path. To control the non-mechanical-interfacing electronic switch, a mechanical lockout device having a protrusion is inserted through the opening of the aperture along the insertion path. To control the mechanical-interfacing electronic switch, a mechanical control part have a protrusion is moveable to interrupt the signal. Methods of locking the non-mechanical-interfacing electronic switch with the mechanical lockout device as well as methods of locking the mechanical control part of the mechanical interfacing electronic switch with the mechanical lockout device are also provided.

The disclosure provides a door switch that improves visibility. The door switch includes an actuator and a sensor. In addition, the door switch is installed so that when a door is closed, a surface of the sensor and an opposite surface of the actuator are in contact with or close to each other, and when the door is open, the surface of the sensor and the opposite surface of the actuator are separated from each other. The actuator outputs a detection signal. A display part for indicating a reception state of the detection signal is formed on the surface of the sensor. The surface of the sensor has a non-opposite region, wherein the non-opposite region is at least a part of the display part not opposite to the opposite surface of the actuator in the reception state.

A resonant inductive sensing system includes an active resonator target that balances losses in the target resonator. The resonant sensor includes a sensor resonator LC circuit and a resonant target including a target resonator Lt/Ct circuit characterized by a loss factor Rts and a target quality factor Qt. The sensor resonator LC circuit and the target resonator Lt/Ct circuit are configured for operation as coupled resonators. The resonant sensor includes a sensor circuit configured to drive the resonant sensor, such that the sensor resonator LC circuit projects a magnetic sensing field based on a sensor quality factor Q, and an active negative resistance circuit Ra coupled to the target resonator Lt/Ct circuit, and configured to substantially cancel the loss factor Rts, such that target quality factor Qt is substantially Qt=([Lt/Ct]/Rts)(RaRts/[RaRtsLt/Ct]).

A safety switch (1) having a reading head (2) and an actuator (3) having a transponder (4) and being movable relative to the reading head (2). Encoded signals of the transponder (4) are detectable by means of the reading head (2). As a means for detecting encoded signals, the reading head (2) has a resonant circuit (6) controlled by a processor unit, with the distance between the actuator (3) and reading head (2) being determined by means of an amplitude evaluation of the signals of the transponder (4) detected with the resonant circuit (6). Control signals are generated as a function of the distance signals thus determined.

The door switch (1) includes an actuator (20) and a sensor (10). When a door is closed, a front surface (S1) of the sensor (10) and an opposite surface of the actuator (20) are in contact with each other, and separated when the door is open. The sensor (10) includes a light source part (150) for emitting detection light according to a reception state of a detection signal outputted from the actuator, a collector (122) for collecting the detection light, a diffuse light guide part (123) formed to be connected to the collector and for diffusing and emitting the detection light collected by the collector, and a back surface display part (121) formed on a back surface (B1) side of the sensor to be in contact with the diffuse light guide part and having a main surface (125) for emitting the detection light emitted from the diffuse light guide part.

A system may include a resonant phase sensing system comprising a resistive-inductive-capacitive sensor and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor, and a compensation circuit. The measurement circuit may be configured to use a phase detector to measure phase information associated with the resistive-inductive-capacitive sensor and based on the phase information, determine a displacement of a metal plate relative to the resistive-inductive-capacitive sensor. The compensation circuit may be configured to detect a change in a physical property associated with the resistive-inductive-capacitive sensor other than the displacement and compensate the phase information to correct for the change in the physical property.