Abstract: An intrusion detection barrier, comprises a coiled wire fence deployable over the ground or over another fence, a sensor wire tensioned between a pair of wire-supporting posts anchored in the ground, an intrusion detector connected to the sensor wire to sense any change in tension thereof, and coupling members coupling the sensor wire to spaced points of the coiled wire fence. Each of the coupling members permits free movement of the sensor wire with respect to the coiled wire fence in the direction of the longitudinal axis of the sensor wire, but restrains movement of the sensor wire with respect to the coiled wire fence in the direction transversely to the longitudinal axis of the sensor wire.

Abstract: A trip-wire guiding device for a protective fence is described including an elongated member attachable to ground-anchoring means intermediate the fence poles and formed with a plurality of openings through which the tensioned trip-wire are passed for maintaining them in parallel space relationship. Each trip-wire is insertable into the opening via a passageway extending from the opening to the edge of the member. A common locking member is received in a channel extending longitudinally through the elongated member aligned with and passing through the passageways, the common locking member being effective to lock the trip-wires in their respective opening against removal through the passageways, but permits their longitudinal movement, such as to cause the detector means to be actuated upon a change in tension in the trip-wires, but to preclude disabling the detector means by merely fastening the tensioned trip-wires to the wire-guiding member or to the common locking member fixed thereto.

Abstract: An underground taut wire intrusion detection system includes a sensor wire enclosed within a conduit adapted to be buried in the ground, the conduit being sufficiently rigid so as to be collapse-resistant when buried in the ground, but being sufficiently flexible in its length such that when disturbed by an attempted intruder the disturbance is transferred to the sensor wire to cause it to actuate a detector.

Abstract: A taut wire intrusion detection system for a fence includes a testing device adapted to be actuated from a central station to apply a mechanical force to the fence wire in order to cause it to simulate an intrusion. The system further includes a testing circuit at the central station for actuating the testing device, and an indicator at the central station which receives the signal from the detector, and thereby indicates the actual response of the detector to the mechanical force.

Abstract: A taut wire type intrusion detection system includes an actuator common to a group of the tensioned wires, which actuator is adapted to actuate a detector upon a change in tension in any of the wires. In some described embodiments, the common actuator includes an actuator wire coupling the plurality of wires to the detector; and in other described embodiments, the common actuator includes an actuator bar coupling the plurality of wires to the detector. Also described is a detector in the form of a ceramic piezoelectric force transducer which outputs an electrical signal proportional to the force applied by the actuator.

Abstract: A force transducer device is described having temperature compensation and including two force transducer units mounted to a fixed support along a common axis by a first mounting member attachable to the fixed support and engaging one end of the two units, and a second mounting member engaging the other end of the units, the device further including force applying means for applying the external force along the common axis of the two units. Also described is an electrical circuit connecting the two force transducer units together such that force-generated signals are added to each other and temperature-generated signals are subtracted from each other, thereby compensating for any temperature variations.

Abstract: An intrusion detector comprises a housing attachable to a fixed support, an electrical switch fixed within the housing and having a switch actuator movable within a longitudinal bore in the housing to actuate the switch. The actuator is attachable to a wire tensioned between it and another fixed support so as to actuate the switch upon stretching or cutting the wire, a spring being disposed within the housing bore and having one end engaging the movable actuator to bias it in the direction opposite to the tensioned wire. A closure member closes one end of the bore and engages the opposite end of the spring and is adjustable to preset the initial non-actuating position of the actuator with respect to the switch.