US1757420A - Head lamp - Google Patents

Description

HEADLAIP May 6,' 1930. R. N. FALGE 1,757,420

Filedoct. 29, 1927 Patented May 6, 1930 ROBERT N. FALGE, OF DETROIT, MICHIGAN, ASSIGNOR TO PATENT OFFICE GENERAL MOTORS RESEARCH CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION OF DELAWARE Haan' LAMP Application filed October 29, 1927. Serial No. 229,684. i

or a shallow annular groove 1n the rim or i constructed to conform with a headlight with a new and flange of the reflector and glue a gasket of cork or cotton cord or similar material on this shelf or groove in position to contact the lens, thus providing a sealing cushion bei 10 tween the reiiector and lens. The process of manufacture of reflectors is such that only a shallow groove can be formed for the cord. so shallow that the cord is easily pulled out of its seat and the seal broken. A particular disadvantage of the cork gasket is that it tends to become brittle and often breaks when the lens is removed to change the bulb in the headlight or make some other adjustment or repair.

It isan object of this invention to provide improved sealing connection between the refiector and lens. It is a further object of the invention to provide an improved gasket for use in this connection, using the less expensive materials available for such purposes. It is a further object of the invention to so construct the adjacent portions of the rim and lens that my improved gasket will be held in place when the lens is removed for changingthe bulb.

Other objects and advantages of the invention will appear in the course of the follow-- ing description, taken in connection with the accompanying drawing and appended claim.

In the drawing:

Figure 1 is a rear view of a separate lens my invention;

Figure 2 is a section on the line 2-2 of Figure 1;

Figure 3 is a vertical longitudinal section through the upper portion of an assembled headlight embodying my invention; and

Figure 4 is an enlarged detail view, partly broien away, of a modified form of gasket cor Referring to Figure 3 of the drawing,1 have.'i;llustrated a portion of a concavo-convext-eflectorvlO which is provided with an annular run 1,2, which extends outward in a plane perpendicular to the axis of the reiector. The outer portion of the rim is recessed at intervals to provide countersunk portions 14: apertured for reception of fastening screws 16.

The numeral 18 indicates a bullet shaped casing, though my invention is `not limited to any particular shape of headlightl Fitting within the rim of the casing is the annular body band 20, fixed within the casing in any usual way, such as by welding. The body band 20 is bent inward slightly to form an annular shoulder 21, then extends forward and then inward, as at 23, in a plane perpendicular to the axis of the casing 18. At this point the band 2O extends rearward and inward, as at 25, to provide a support for reflector 10. j

A number of threaded apertures are provided in the portion 23 of the band for receiving the respective screws 16 for adjustably positioning the reflector l() relative to the casing 18.

The lens, as shown in Figures 1 and 2, comprises a glass disc 24 provided with the usual corrugations, though my invention is equally applicable with a headlight comprising a fluted reflector' and a plain lens. The lens is formed on the inner side with a groove 26 which is substantially semi-circular in cross section. The groove extends complete- 1y about the lens except for a small plain segment 27 at ,the lower part. Held within the groove and forming a sealing cushion .between the lens and reiiector, as shown in Figure 3, is the gasket 30.

The gasket comprises an ordinary closely woven cotton cord. The gasket may or may not be glued into place. The cord rests on the surface of the rim 12 of the reflector and is compressed slightly when the lens is {ixld firmly in position in the assembled headig t.

The means for holding the lens in position comprises the door ring 34 the outer surface of which conforms to the outer surface of casing 18. It may beA noted that the front side of the lens is shaped adjacent the rim to provide an annular groove 36, and the door ring is provided with an inward extendnarrower and ing fiange 38 which is crimped rearward slightly to fit within groove 36. Within the door ring is a reinforcing ring 40, which C onforms roughly to the shape of the door ring 34, Reinforcing ring 40 is provided wlth an inward extending-'liangek 42 which follows the contour of the door ring flange 38 and contacts with the forward side of the lens adjacent g ove 36. The axially extending portion o reinforcing ring 40 is bent outward to contl t with door ring 34 as illustrated and ext/ends Hush with the edge of the door ring where the ring 40 abuts against the annular shoulder 21 of the body bandv 20. The door ring 34 is held snugly against casing 18 by any usual or desirable fastening means (not shown).

With the construction just described, the flange on the reflector may be comparatively narrow as the cord gasket is quite narrow and the fastening screws are partially countersunk in the edge. of "the flange. In prior constructions it has been the practice to eX- tend this ange outward a short distance,l

then bend it rearward and outward for providing a seat for a comparatively large cork gasket. The flange must extend out some `distance still farther beyond the gasket in order to provide a hole for reception of the fastening screw. Myl invention makesY it feasible to provide a flange on the reflector which is narrower than the flange of the conventional reflector by an amount slightly greater than the 'width he cork gasket of casing. This permits the makes possible a betterl and more desirable design of headlamp. These results are obtained by forming the groove in the lens, which may be readily accomplished. Production conditions are such with the reliector that only a shallow groove in the rim of the reflector ispracticable.

In Figure V4 I have illustrated a modified an more expensive form of cord gasket. This comprises a helical steel wire 50, such as a piano wire, over which is drawn a cover or sleeve 52 which may be of thin cotton fabric. This form retains its shape a little better than the plain cotton' core and tends to remain more firmly seated in the groove 26 in the lens. It also permits greater conimerc'ial variations in the spacing between i lens and reector where the latter is fastened to the shoulder on the housing and thereby avoids poor sealing, on the one hand, and, on the other, distorted doors.

I claim:

An automobile headlamp comprising a' casing, a lreiector in the casing, a lens fitted over the rclector'and provided with a peripheral groove for receiving a sealing-gasket, a gasket in the groove, said reflector being provided with a narrow outturned flange having -length to prevent a plane surface adapted to engagethe sealing gasket throughout substantially its entire entrance of dust and moisture, said flange bein provided with dis continuous countersun t, portions outwardly of the line of contact with said gasket, means engaging, said co'untersun'k portions andthe casing for securing the refiector to the casing, and meansfor clamping the lens to thel re- Hector andy casing.

In testimony whereof I alx my si ature.

ROBERT N. FATIGE.

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