Headlamp with displacement gauge

Art automobile headlamp having a displacement gauge that facilitates the rotation of a zeroing adjustment screw. The displacement gauge is mounted between a lamp body and a reflector, which is supported rotatably by aiming mechanisms in the lamp body and is employed to measure the amount of rightward or leftward displacement of the light beam axis of the reflector. A zeroing adjustment screw for the displacement gauge passes through and extends rearward beyond the lamp body. A crown gear, employed as a screwdriver engaging fitting to rotate the zeroing adjustment screw, is fitted over the end of the zeroing adjustment screw at the rear of the lamp body. With this arrangement, a screwdriver can be inserted from above the lamp body to engage the crown gear and to rotate the zeroing adjustment screw. In an alternate embodiment, a drive shaft is provided having a bevel gear at its lower end engaging the crown gear and a screwdriver-engaging fitting at its upper end.

What is claimed is:

1. An automobile headlamp comprising:

a fixed member;

a movable member including a light source and a reflector having an optical light beam axis;

an aiming mechanism for pivotally supporting said movable member on said fixed member;

a displacement gauge, said displacement gauge being mounted between said fixed member and said movable member for measuring an amount of rightward or leftward movement of said light beam axis of said movable member, said displacement gauge comprising a wherein horizontal movement of said movable member causes said slide pin to move within said movable holder;

a gear fitted over a rearward extending segment of said zeroing adjustment screw at an external rear wall of said fixed member, said gear being engagable by a screwdriver inserted from above said fixed member, said gear comprising a crown gear having teeth facing said fixed member;

a screwdriver guide for guiding a screwdriver to said crown gear, said screwdriver guide being secured to an external surface of said fixed member, said screwdriver guide having an arched notch for positioning a head of said screwdriver and preventing disengagement of said screwdriver from said crown gear.

2. An automobile headlamp comprising:

a fixed member;

a movable member including a light source and a reflector having an optical light beam axis;

an aiming mechanism for pivotally supporting said movable member on said fixed member;

a displacement gauge, said displacement gauge being mounted between said fixed member and said movable member for measuring an amount of rightward or leftward movement of said light beam axis of said movable member, said displacement gauge comprising a cylindrical fixed holder penetrating an aperture in and fixed to a rear wall of said fixed member, said cylindrical fixed holder having a pipe-shaped cross section and a slot along a top surface thereof and comprising a flanged portion extending above and below said aperture in said rear wall of said fixed member, a cylindrical movable holder inserted in and movable forward and backward within said fixed holder, said cylindrical movable holder having a generally cylindrical configuration and a rectangular vertical cross section, slide pin inserted into and movable within said movable holder, said slide pin having a protruding portion slidably received in said slot of said fixed holder, scale lines being inscribed on a portion of said slide pin exposed by said slot and a reference line being inscribed on an upper surface of said movable holder adjacent said slot, a compressed coil spring retained in said movable holder and urging said slide pin forward through a front opening in said movable holder, said zeroing adjustment screw passing through and being supported by said fixed holder and being screwed into and retained within said movable holder, a zeroing adjustment screw extending rearward beyond said fixed member, and a nut member threadedly joined to said adjustment screw and fitted to a rear opening of said movable holder, said coil spring being disposed between said slide pin and said nut member so as to drive said slide pin forward so that a forward face of said slide pin contacts a vertical wall of said movable member cylindrical fixed holder penetrating an aperture in and fixed to a 7 rear wall of said fixed member, said cylindrical fixed holder having a pipe-shaped cross section and a slot along a top surface thereof and comprising a flanged portion extending above and below said aperture in said rear wall of said fixed member, a cylindrical movable holder inserted into and movable forward and backward within said fixed holder, said cylindrical movable holder having a generally cylindrical configuration and a rectangular vertical cross section, a slide pin inserted in and movable within said movable holder, said slide pin having a protruding portion slidably received in said slot of said fixed holder, scale lines being inscribed on a portion of said slide pin exposed by said slot and a reference line being inscribed on an upper surface of said movable holder adjacent said slot, a compressed coil spring retained in said movable holder and urging said slide pin forward through a front opening in said movable holder, said zeroing adjustment screw passing through and being supported by said fixed holder and being screwed into and retained within said movable holder, a zeroing adjustment screw extending rearward beyond said fixed member, a nut member threadedly joined to said adjustment screw and fitted to a rear opening of said movable holder, said coil spring being disposed between said slide pin and said nut member so as to drive said slide pin forward so that a forward face of said slide pin contacts a vertical wall of said movable member wherein horizontal movement of said movable member causes said slide pin to move within said movable holder;

a crown gear fitted over a rearward extending segment of said zeroing adjustment screw at an external rear wall of said fixed member;

a drive shaft extending upward from said first gear means, said drive shaft having a screwdriver-engaging recess at an upper end thereof;

a bevel gear fixed to a lower end of said drive shaft, said bevel gear engaging said crown gear; and

a pair of brackets for rotatably supporting said drive shaft, said brackets being fixed to said rear wall of said fixed member.