Patent Application
20100213814
This invention relates to automobile headlights and more particularly to those headlights wherein a replaceable lamp unit is utilized.
Automobile headlights wherein a replaceable lamp unit is employed as the light source are well known in the art. The instant invention is related to lamps of the variety described above. In particular, the invention defines a replaceable lamp unit, which assures that the electric lamp utilized therewith will be maintained in strict alignment as is necessary in automotive headlights.
The replaceable lamp defined herein assures that alignment of the electric lamp employed therewith will be maintained. That is, alignment of the glass envelope of the lamp relative to the unit's holder is provided such that the filament structure within the envelope (either a single coiled filament or two, spaced coiled filaments) will be accurately aligned relative to the optical axis of the reflector when the lamp unit is oriented within the reflector's rear opening. Such alignment is deemed critical to assure optimum headlight output in the direction(s) desired.
As also described herein, a preferred light source (which constitutes an important part of the replaceable lamp unit) is an electric lamp of the tungsten-halogen variety. One example of such a lamp is shown in U.S. Pat. No. 3,829,719, Westlund, Jr., et al., which is assigned to the assignee of the instant invention. In tungsten-halogen lamps, the tungsten, which constitutes the filament material, is evaporated from the filament during lamp operations and combines with the halogen to form a gaseous halide, the halide preventing the tungsten from depositing on the internal wall of the lamp envelope. Upon returning to the filament structure the halide decomposes, resulting in the deposition of tungsten back onto the filament structure and the release of the halogen gas to assure continuation on the cycle. The halogen cycle is well known in the art and lamps employing it have been used for some time. In the case of the two-beam (dual filament) lamp, a typical tungsten-halogen lamp provides about 65 watts when operated at high beam and about 55 watts at low beam. As stated, it is critical that the filament structure of the lamp within the automobile headlight be aligned relative to the reflector to provide optimum output of the finished headlight. Such alignment constitutes an important feature of the replaceable lamp unit defined herein.
It is, therefore, an object of the invention to obviate the disadvantages of the prior art.
It is another object of the invention to enhance the alignment of automotive headlights.
Yet another object of the invention is the improvement of automotive headlights.
These objects are accomplished, in one aspect of the invention, by the provision of an automotive headlamp comprising a light source capsule including a seal area; a retainer affixed to the seal area, a plastic base including a cavity arrayed about an axis and a circumferential wall about the cavity; an annular receptor associated with the circumferential wall, a plurality of axial slots formed in the circumferential wall, the slots forming segments of a circle arching around the axis, the slots being further defined by angularly located end stops; a plurality of metal inserts having base ends sized and shaped to closely fit the axial slots positioned in the slots, each of the metal inserts having one or more extended resilient fingers provided with a retainer engager engaging and supporting the retainer, and a retention feature formed with each of the base ends, the retention feature engaging the annular receptor.
The use of the retainer and resilient fingers on the metal inserts allows for accurate positioning of the lamp relative to the plastic holder. Further, it removes any support function from the lamp lead-ins, allowing greater flexibility of the lead-in attachment to the necessary socket prongs.
For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims taken in conjunction with the above-described drawings.
Referring now to the drawings with greater particularly, there is shown in
A plastic base 18 includes a cavity 20 arrayed about an axis 22 and has a circumferential wall 24 thereabout. Axial slots 26 are formed in the circumferential wall 24, these slots 26 forming segments of a circle arching around the axis 22. The slots 26 are further defined by angularly located end stops 28. The slots 26 and stops 28 are best seen in
A plurality of metal inserts 30, preferably formed from a stamped metal such as 301 stainless steel, and having base ends 32 sized and shaped to closely fit the axial slots 26 are frictionally positioned in the slots 26, each of the metal inserts 30 having an extended resilient finger 32a provided with a retainer engager 34 for engaging and supporting the retainer 16. A retention feature 36, in the form of a prong 38, is struck from the base end 32, and engages the circumferential wall 24, drastically increasing the force necessary to remove the inserts, from an average of 9.9 lbf to 22.5 lbf (thereby increasing the strength of the entire unit) as shown in the graph depicted in
If desired, the inserts 30 can be provided with up-standing shields 40 arrayed on either side of the fingers 32a for the purpose, among others, of blocking light that may emerge from the capsule press area.
During the assembly of the light source capsule 12 to the base 18, the retainer 16 is positioned with the resilient fingers 32a and the lead-ins 14a and 14b connected to the necessary socket prongs (not shown). At this point the light source capsule 12 and its retainer can be moved about the axis 22 to achieve the proper filament alignment, at which time the retainer engagers 34 are welded to the retainer wall 16a, preferably by laser welding, although other forms of attachment can be employed.
Thus, there is provided a ruggedized, alignment-correct automotive headlamp that is economical to produce.
While there have been shown and described what are at present considered to be the preferred embodiments of the invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the scope of the invention as defined by the appended claims.
