Speed detector for traffic control

Claim 1

An arrangement for monitoring traffic comprising: an elongate strip member adapted to be placed on a road surface, said elongate strip member including a base layer; at least two longitudinally extending and laterally spaced apart electrical contact means being provided on the upper surface of said base layer; a dielectric spacer layer extending over the upper surface of said base layer; a plurality of longitudinally and laterally spaced apart apertures being provided in said dielectric layer, so as to be located substantially over the electrical contact means provided on the upper surface of said base layer; said apertures in said dielectric layer being formed of at least two sets of longitudinally spaced apart apertures, each said set being laterally spaced apart one from the other by a distance over which monitoring and/or timing of traffic is to take place; a resilient material layer extending over said dielectric spacer layer; at least two further longitudinally extending and laterally spaced apart electrical contact means being provided on the lower surface of said resilient material layer so as to be located substantially over said apertures; said longitudinally and laterally spaced apart apertures, and said respective electrical contact means, forming a plurality of longitudinally spaced apart switches, each of said switches being connected to monitoring and/or timing means associated with said strip member; and means being provided to supply voltage across said electrical contact means; whereby upon one or more vehicles passing over said elongate strip member, one or more of said switches will be actuated by said resiliently mounted electrical contact means being caused to make contact with said base layer electrical contact means through one or more of said apertures, to thereby actuate said monitoring and/or timing means.