Force-responsive detectors and systems

摘要

A force-responsive sensor is disclosed, such as for incorporation in a safety system for detecting an obstruction in a window opening closable by a motorized slidable window pane. The sensor is mounted within a hollow volume in flexible material running alongside the top frame member of the window opening. The sensor comprises an upper flexible and resilient layer supporting a continuous longitudinally extending conductive strip. This upper layer is spaced from a similar layer supporting a continuous longitudinally extending conductive strip, the two layers being separated from each other by insulating spacers spaced at intervals along the length of the sensor. Any obstruction in the window opening is carried upwardly by the rising window glass and applies a force to the flexible material. A ridge in the lower wall of the hollow chamber responds by causing contact between the two conductive strips to produce a warning signal. The construction is such that the sensor responds not only to a point force but also to a force applied over a substantial length of the window frame.