PURPOSE: To eliminate the dead ground of illumination, by interlocking the steerling system with the headlamp system so that the headlamp and the front wheels are directed in the same way.

CONSTITUTION: In changing the direction of front wheels in accordance with the control of a steering wheel 1, a concave female corrugated plate 24 which is matched with a convex male one at the tip of a steering shaft 2 is interlocked with an upper gear engaged with the female plate. At the same time, gears 7, 8 and 9, 10 supported by a universal joint rod 6 and connecting rod 11 resepctively are also interlocked with to turn the headlamp fitted solidly together with the gear 10 at the tip of a shaft 31.