Automatic leveling device for automotive vehicle headlamps

Abstract

An automatic leveling device for automotive vehicle headlamps is described. The device automatically stops driving an actuator if the actuator is determined to be failing, while the other normally operating actuator is used to perform a leveling of the optical axis of the headlamp as close to a proper leveling as possible. In an implementation, a pair of left and right headlamps,L,,R have optical axes L that are tilted individually by driving left and right actuators,L,,R, respectively. A single control unit,simultaneously controls the driving of the left and right actuators,L,,R. A vehicle speed detection means,, a pitch angle detection means,, and failure detection means,L,,R are included. The control unit,controls the driving of the actuators,L,,R based on a detected pitch angle such that the optical axes of the headlamps stay in a certain inclined state with respect to the surface of a road, and when an actuator is determined to be failing, the CPU unit,stops driving the failing actuator, while driving the normally operating actuator, thereby performing a leveling of the optical axis of the headlamp as close to a proper leveling as possible.