Abstract: A safety lock for a closing-off device which can be opened, has an actuating unit with an actuator which is guided in a displaceable manner, and has a locking unit into which the actuator, with the closing-off device closed, can be pushed and can be locked via an electromagnetically actuable, pivotable catch, by way of interengaging engagement surfaces, the actuator has a trigger element and the locking unit has a response element which, with the actuator pushed in, reacts to the trigger element by emitting an electric signal which triggers the locking action, in the case of which the catch can be pivoted about an axis extending parallel to the movement direction of the actuator, and the engagement surfaces of the catch and of the actuator run perpendicularly to the movement direction.

Abstract: A device with a safety circuit with an armature activated by a solenoid activates an electromagnet. The device has a switch connected in series to the solenoid, a device temporarily interrupting application of the voltage, first and second clock generators, first and second resistors, and a current detection switch. DC voltage is applied to the solenoid when the switch is closed. The voltage is interrupted when a predetermined current flowing through the solenoid is detected. The first clock generator actuates the switch during a predetermined first clock cycle. The detection switch detects current flowing through the solenoid. The first resistor, in conjunction with the response threshold of the current detection switch, determines the holding current for the armature. The second resistor generates an attraction current for the armature when activated by the second clock generator in a predetermined second clock cycle partially overlapping the first clock cycle.

Abstract: The invention relates to the detection of the position of an object which can be moved along an acoustic-signal conductor of ferromagnetic material, in which an acoustic signal is incoupled in a clocked manner into the acoustic-signal conductor by means of a signal input coupler connected to a signal transmitter, extracted by means of a signal output coupler and the extracted signal is evaluated by an evaluating circuit for generating a signal representative of the instantaneous position of the object, wherein an opposite magnetic field for the magnetic field generated by the acoustic signal is incoupled in each case after the incouplion of the acoustic signal.

Abstract: A monitoring device for a protected area of a machinery installation, the area being accessible through at least one access opening which can be closed off by an element, such as a door, shutter, or the like, which is movable between an open position and a closed position. The monitoring device being arranged adjacent to the movable element and comprising a safety switch having a housing, an evaluation device, a movable element positionable between a closed and an open position, a coded release mechanism located on the movable element, and a read head for reading the coded release mechanism when the movable element is in the closed position. The safety switch being further provided with an actuator bearing a release mechanism, and which, in a locking position in the housing, locks the movable element in its closed position. The housing having a receiving space for the actuator such that the release mechanism is located adjacent to the read head when the actuator is in the locking position in the housing.

Abstract: The invention relates to an apparatus for detecting the position of an object moveable along a predetermined travel path, comprising: an acoustic signal waveguide extending along the travel path and having a predetermined, uniform speed of propagation of sound; a signal input coupler located on the moveable object, to couple a clocked acoustic signal into the acoustic signal waveguide, at least one signal output coupler being arranged at one end of the acoustic signal waveguide and being connected to an evaluation unit for determining the propagation time of the sound signal from a position at which it is coupled in to the at least one signal output coupler and for generating a signal representative of the instantaneous position of the moveable object on the travel path, wherein the signal input coupler couples in, as acoustic signal, adjacent pulses having a varying time interval.

Abstract: The invention relates to an apparatus for detecting the position of an object moveable along a predetermined travel path, comprising: an acoustic signal waveguide extending along the travel path and having a predetermined, uniform speed of propagation of sound; a signal input coupler located on the moveable object, to couple a clocked acoustic signal into the acoustic signal waveguide, signal output couplers at both ends of the acoustic signal waveguide and each being connected to an evaluation unit for determining the propagation-time difference of the sound signal from a position at which it is coupled in to the signal output couplers and for generating a signal representative of the instantaneous position of the moveable object on the travel path, wherein a calibration signal input coupler connected to a calibration acoustic signal generator for a calibration acoustic signal is provided on one of the signal output couplers, the evaluation unit calculating a correction variable for subsequent determinat

Abstract: An apparatus for detecting the position of a moveable object along a path such as a rail or a wire. The apparatus includes an acoustic signal conductor, a signal input coupler, and a signal extractor. The acoustic signal conductor extends along the travel path and has a predetermined, uniform speed at which sound is propagated. The signal input coupler is located on the moveable object to couple a clocked acoustic signal into the acoustic signal waveguide. The signal extractor is arranged at one end of the acoustic signal waveguide and is connected to an evaluation unit for determining the propagation-time of the sound signal from a position at which the sound signal is coupled to the signal extractor to accordingly generate a signal representative of the instantaneous position of the moveable object on the travel path. A sensor on the acoustic signal conductor is actuated by being passed over by the moveable object.

Abstract: The invention relates to a contactless safety switch for detecting the shut position of a shutting part in relation to a closeable part, with a switch unit, supplied with current by an electrical supply source on one of the parts and with a trip arranged on the other part and comprising a magnet. In this case, the switch unit comprises a transmission circuit with a clock-signal generator and with a transmission coil, a receiver circuit connected to an evaluation unit and having at least one receiver coil and also a Hall sensor responding to the magnet, and the trip comprises a trip coil which is capable, in the shut position, of being excited inductively by the transmission coil and exciting the receiver coil, while, in the shut position, the evaluation unit triggers a clearance path when the Hall sensor is activated via the magnet.

Abstract: The invention relates to an actuator for a safety switch provided with at least one insertion slot with inclined insertion guides for the actuator, having a holder which can be fastened to a part whose open and closed positions are to be monitored, and which is fitted with the key mounted on it such that the said key can be moved, the key comprising a foot, and the holder being provided with a recess for the key on the side facing the key and with a bearing for the foot, the said bearing extending around the recess and allowing the foot to be displaced and rotated.

Abstract: A safety switch, operable by a removable coded actuator, is designed for mounting on a support surface in four different orientations. The switch has a substantially square cross-section and grooves or holes for receiving mounting fasteners extend across each side of the switch housing, the grooves being located in a common plane intermediate the ends of the housing.

Abstract: The operability of a plurality of sensors is monitored by periodically interrogating the sensors individually and evaluating the responses to the interrogation. The sensors are each connected to a two-conductor power supply bus via a signal processor and an interface. The information exchanged via the bus is in the form of binary coded signals generated by clocking the bus voltage.

Abstract: The position of an object which is moved along a prescribed path, for example an elevator cage, is continuously and accurately monitored by coupling an acoustic signal generator carried by the object to an acoustic signal conductor which extends along the path, the acoustic signal conductor being characterized by the velocity of sound propagation therealong being uniform and constant. The position of the object is calculated by processing signals generated by transducers located at the opposite ends of the acoustic signal conductor, the signal processing determining the delay between receipt of a sound signal originating at the object at the opposite ends of the conductor.

Abstract: A key operable electrical safety switch includes a housing and a switch operator that is operated by an actuator. A slot in the housing receives the actuator. A plurality of pin stacks, the stacks having axes that are parallel and perpendicular to the slot, are spring biased to extend into the slot. At least one of the pins engages the actuator to lock it in a fixed position relative to the housing. The actuator is released from the locked position, and displaced a predetermined stroke to actuate the switch operator and thereby change the state of the switch contacts, by a key. The key has a coded pattern of pin receiving holes corresponding to the locking pins to align the pins and release the actuator. The pins are correspondingly codeable.

Abstract: A key operable safety switch includes a housing and a switch operator that is operated by an actuator. A slot in the housing receives the actuator. A plurality of discs independently rotatably mounted on an axle, the discs each having a radial recess aligned with the slot and cam-like control grooves, form a roller. The actuator has a coded pattern or actuation portions corresponding to each disc radial recess. Insertion of the actuator engages the actuation portions with the radial recesses causing the discs to be rotated as a whole. A pin mounted to the switch operator and transversely disposed in the control grooves is axially displaced by rotation of the discs. The switch operator is displaced a predetermined stroke to actuate the switch.