COLLISION ALARM DEVICE FOR VEHICLES

摘要

PURPOSE: To assure minimum safe distance between vehicles and extend life of luminous element by prolonging the illumination interval of the luminous element in accordance with the lowering of speed of the car concerned. CONSTITUTION: An operation circuit 41 sends a distance detection command signal to a drive signal generation circuit 11, takes in a distance signal R to a preceding car from a counter 20 and a car velocity signal Vf of the present car from a car velocity sensor 31, and calculates the relative velocity (d/dt)R between the preceding car and the present car and the velocity Va of the preceding car. Then, the difference in stop distances VF<2> /2α, Va<2> /2α(whereαis deceleration performance) between the preceding car and the present car is calculated and the collision is prenoticed based on the distance by adding set 42 free running distance Vf.Td (is the time to brake) of the car concerned. Altogether, when the preceding car is stop (Va=0) and Vf.Td+Vf<2> /2α>=R, when the preceding car is running and (d/dt)R >= predetermined speed C, and when (d/dt)R=R, alarm 52 functions. At this moment, the circuit 41 takes in the speed signal Vf and direct the circuit 11 to prolong the illumination interval of luminous elements LD-L, LD-C, LD-R in accordance with the lowering of the speed Vf.