Patent Application
20100213815
This invention relates to automobile headlights and more particularly to those headlights wherein a replaceable lamp unit is used.
Automobile headlights wherein a replaceable lamp unit is used 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 used therewith in strict alignment as is necessary in automotive headlights.
The replaceable lamp defined herein assures that alignment of the electric lamp used therewith is 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) is accurately aligned relative to the optical axis of the reflector when the lamp unit is oriented within the reflectors 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 using 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 headlight comprising a light source capsule including a seal area; a cup-shaped retainer affixed to the seal area, the cup-shaped retainer having an upper surface, an outer wall surface and an inner wall surface; a plastic base including a cavity arrayed about and axis and a circumferential wall about the cavity; a pair of oppositely disposed, axial slots formed in the circumferential wall, the slots forming segments of a circle arching around the axis, the slots being further defined by a pair of oppositely disposed end stops; a pair 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 two resilient fingers each having a retainer engager formed to engage the inner wall surface of the retainer and engaging and supporting the retainer; and retention features formed with the base ends, the retention features engaging the circumferential wall.
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. Positioning the retainer engagers on the inside of the retainer smoothes the entire design and minimizes the risk of accidentally striking one of the resilient fingers (during insertion into a reflector) and disturbing the lamp alignment.
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. Two 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 two, angularly located end stops 28. The slots 26 and stops 28 are best seen in
A pair of metal inserts 30 (only one of which is shown in
If desired, the inserts 30 can be provided with up-standing shields arrayed on either side of the fingers 32a for the purpose, among others, of blocking light that may emerge from the capsule press area; aiding in the alignment of the metal insert 30 during assembly; and further increase in the force necessary for pull-out during assembly.
During the assembly of the light source capsule 12 to the base 18, the retainer 16 is positioned with the resilient fingers 32a (and their corresponding retainer 34 contacting the inner wall 16c) 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 alignment, at which time the retainer engagers are welded to the retainer inner wall 16c, preferably by laser welding, although other forms of attachment can be used. Positional movement is easily achieved by virtue of the shape of the retainer engagers, which shape is in the form of a spherical section. Thus, contact with the inner wall 16c is by a single point on each retainer engager, which greatly reduces the energy necessary to move the lamp and achieve the necessary alignment.
Thus, there is provided a ruggedized, alignment-correct automotive headlamp that is economical to produce. Positional movement of the retainer about the retainer engagers is easily accomplished, and the positioning of the retainer engagers on the inner wall of the retainer prevents subsequent damage when the lamp is inserted into a reflector.
While there have been shown and described what are at present considered to be the preferred embodiments of the invention, it is 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.
