Illumination – Illuminated scale or dial – Edge illuminated modifier or light rod/pipe
Reexamination Certificate
1998-04-13
2001-01-30
O'Shea, Sandra (Department: 2875)
Illumination
Illuminated scale or dial
Edge illuminated modifier or light rod/pipe
C362S027000, C362S023000, C362S035000, C362S489000, C362S482000, C362S511000, C362S543000
Reexamination Certificate
active
06179429
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to automotive instrument cluster dials, and more specifically, to illumination of such dials.
BACKGROUND OF THE INVENTION
Conventional instrument cluster dials are illuminated by incorporating a small lamp on the dial or by using light conducting transparent pointer material optically coupled to a near-by light source. In the case of the small lamp on the dial, it is expensive to provide a lamp that is sufficiently small and yet sufficiently bright to illuminate the dial.
In the case of the light conduction method for dial illumination, it is the usual practice to transmit light from a remote lamp through a transparent light guide and into the dial. Problematically, illumination in such a manner requires many reflections before reaching the dial and only a small portion of the source light is eventually received by the dial, thereby resulting in a dimly lit dial. Further, a single, cone shaped reflective surface is used to couple the light into the dial. A single reflective surface has a limited usable reflective surface area with which to couple light into the dial. The limited surface area in conjunction with the small portion of light being received thereby only amplifies the dimly lit dial problem.
Recent automotive designs have necessitated reducing the packaging space or depth of the instrument cluster. Reducing the cluster depth has necessitated the use of smaller, lower power lamps for back lighting the cluster and illuminating the dial. These small lamps are less bright than the larger lamps used with the previous thicker clusters, which only amplifies the dimly lit dial problem described above.
One way to remedy the lower power lamp problem is to simply add additional lamps to brighten the dial. This solution, however, adds complexity and cost to the instrument cluster.
What is desired, therefore, is a mechanism to sufficiently illuminate an instrument cluster dial, which uses a minimum number of low power lamps, thereby minimizing cost and complexity.
SUMMARY OF THE INVENTION
Responsive to the deficiencies in the prior art, the present invention provides an automotive vehicle illumination mechanism for an instrument cluster dial, including a transparent light guide having a generally planar front surface, at least one semi-circular light socket, and at least one dial socket. A light source is arranged within the light socket for directing light into the light guide. A lens having a focal axis is arranged adjacent the light source and within the light socket for collecting the light from the light source and transmitting the light with a predetermined spread angle toward the dial socket. Finally, a plurality of reflective surfaces, distributed in a fan-like arrangement about the focal axis and intermediate the lens and the dial socket, redirect light received from the lens toward the dial.
In a preferred embodiment of the present invention, the plurality of reflective surfaces have generally curvilinear cross sections, which are concave with respect to the lens.
An object of the present invention is to sufficiently illuminate an instrument cluster dial with a minimum number of low power lamps.
An advantage of the present invention is the utilization of a plurality of reflective curvilinear surfaces to direct light into the dial. The plurality of reflective surfaces, distributed in a fan-like arrangement about the focal axis of the lens, function to reflect substantially more light into the dial than conventional single reflector mechanisms, thereby sufficiently illuminating the dial even though low power lamps are used.
REFERENCES:
patent: 2805505 (1957-09-01), Hardesty
patent: 2831453 (1958-04-01), Hardesty
patent: 2848830 (1958-08-01), Dmitriev et al.
patent: 3143098 (1964-08-01), Blackwell
patent: 4233927 (1980-11-01), Oikawa et al.
patent: 4258317 (1981-03-01), Dubauskas
patent: 4323951 (1982-04-01), Pasco
patent: 4404522 (1983-09-01), Pucciarello
patent: 4415855 (1983-11-01), Dubauskas
patent: 4447860 (1984-05-01), Stone et al.
patent: 4449024 (1984-05-01), Stracener
patent: 4714983 (1987-12-01), Lang
patent: 4882659 (1989-11-01), Gloudemans
patent: 4884058 (1989-11-01), Ikeda
patent: 5003433 (1991-03-01), Fournier
patent: 5142456 (1992-08-01), Murphy
patent: 5436038 (1995-07-01), Gelb
patent: 5458082 (1995-10-01), Cookingham
patent: 5556187 (1996-09-01), Furaya et al.
patent: 5578985 (1996-11-01), Cremers et al.
patent: 5678912 (1997-10-01), Ayres et al.
patent: 0 602 385 (1993-11-01), None
patent: 1077802 (1997-08-01), None
Kalashnikov Sergey
Sheldon Daniel Frank
Hodges Leslie C.
Negron Ismael
O'Shea Sandra
Visteon Global Technologies Inc.
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