Aiming mechanism for vehicular headlamp

摘要

An automobile headlamp aiming mechanism including a tilting member supported on a stationary member so as to be capable of tilting and defining the illumination angle of the headlamp beam. A cylindrical nut member is rotatably supported by a bearing formed on the stationary member. An aiming screw threadedly joined with the nut member extends forward and backward in threaded connection with the nut member, the aiming screw being prevented from moving with respect to the nut member, and moving forward and backward in the axial direction to tilt the tilting member. The aiming mechanism allows the nut member to rotate smoothly when a bevel gear formed on the nut member is engaged with a driver inserted in a direction at a right angle with respect to the longitudinal axis of the aiming screw. Concavo-convex engaging parts for engaging the nut member with the bearing are provided on predetermined confronting faces in sliding contact between the bearing and the nut member, the nut member engaging parts operating to prevent the nut member from rotating in response to vibration or the like. The nut member is supported elastically in the axial direction in such a manner that the engagement of the engaging parts is released by the thrust generated when the nut member is rotated.