Pressure sensitive switchmats.

摘要

An electrical switchmat having a normally open switch which is closed under a predetermined minimum load, the switchmat comprising a first metal sheet 3 separated from a load-bearing sheet 2 having an electrically conductive surface by resiliently compressible, non-conductive materials 5 and 7, and a plurality of bridging elements 6 positioned between the sheets such that when at least said predetermined minimum load is applied to the loadbearing sheet 2, the non-conductive material 5 and 7 compresses and one or more of the bridging elements establishes a conductive path between the sheets, the load-bearing sheet 2 being substantially rigid under the intended operating load of the switchmat and the bridging elements 6 being constructed and arranged such that when the load-bearing sheet is subjected to substantial overload, it is supported by the bridging elements 6 thereby preventing damage to the non-conductive materials 5 and 7.