Patent ID: 6510378
Filing Date: 2003-01-21
Classification: G08G

Abstract:
A traffic control system for timely signalling the presence of an obstruction on a roadway which includes a plurality of vehicle detecting units (10) powered by an electric supply voltage spaced along said roadway, each vehicle detecting unit including a control plant (11) comprising:a) means for sensing the presence of motor vehicles including a signal emitting unit (13) and a signal receiving unit (14); b) timer means for receiving signals from said sensing means indicating the presence of motor vehicles and for filtering said signals so as to pass only signals longer than a pre-established time; c) a central control unit (16) interfaced with said timer means to receive the signals passed by said timer means; d) alarm means (17,18) communicating with said central control unit (16) and actuated thereby upon receipt by said central control unit of a signal from said timer means; e) radio transmitter units (19,20) activated by said central control unit (16) upon receipt by said central control unit of a signal from said timer means to transmit a signal to adjacent detecting units which activates through a respective central control means associated with said adjacent detecting units alarm means of said adjacent detecting units; and f) radio receiver units (21,22) operatively communicating with said central control unit (16) for receiving signals from adjacent detecting units to activate said alarm means (17,18).