| 摘要 |
<p>PROBLEM TO BE SOLVED: To steppedly or continuously adjust the radiation distance of a vehicle front radiation light, from a high beam to a low beam, by moving a light source in an optical axial direction by using a driving means to change a relative position with a reflector. SOLUTION: A ball screw bar 8 is rotated via a gear 11, etc., by driving a motor 12 to make a lighting control circuit unit 30 guided by a guiding bar to be moved forward and backward, and a discharge bulb 21, integrated with the unit 30, is also moved forward and backward to change the relative position with a reflector 5. When the discharge bulb 21 is in an advanced position, radiated light reflected by the reflector 5 is advanced obliquely downward to constitute a lower beam; and when the discharge bulb 21 is in a retreated position, radiated light reflected by the reflector 5 at the same position is advanced in an upper part than the previous radiated light to constitute a high beam. Both beams can be switchedly formed by thus moving the discharge bulb 21 in forward and backward directions via a gear acceleration transmitting mechanism, composed of the gear 11, etc., and the ball screw bar 8, by driving the motor 12.</p> |
