Illumination – Light source and modifier – Including reflector
Patent
1983-08-02
1985-04-30
Lechert, Jr., Stephen J.
Illumination
Light source and modifier
Including reflector
362341, 362347, 362362, 362377, 362396, 362417, 362444, F21V 700
Patent
active
045147930
DESCRIPTION:
BRIEF SUMMARY
This invention relates to a reflector system for securing to a light source.
Reflectors for lighting purposes are most often manufactured of anodized aluminium plate and are secured to the light fitting, in that the reflectors are normally produced especially for use in connection with the individual types of fittings.
However, many light sources are to be found, for example fluorescent tubes, which are mounted in fittings without reflectors or which are disposed freely outside the fitting. When for reasons of increasing energy prices it is desired to increase the illumination without exchanging the lamps for lamps having a greater energy consumption, one can provide them with suitable light reflectors. In order to make the assembly independent of the shape of the fitting, it is most expedient for the reflector to be mounted directly on the light source.
Reflectors for mounting directly on to fluorescent tubes are known, for example executed in plastic materials and provided with various means of reflection. It is, however, more expedient to produce the reflector of anodized pure aluminum, the reason being that this material is more robust and stable in shape and, furthermore, its reflecting characteristics are more durable.
In the following, the invention is explained in connection with the use of an elongated light source, and a normal fluorescent tube has been chosen as an example.
The actual cross-sectional curve of the reflector, which does not form a direct part of the present invention, conforms mainly to that shape known, for example, from British Pat. No. 884,068, the lower part of the reflector cross-sectional curve turning downwards to form a light output aperture which strongly reduces the light intensity immediately outside an angle which is desired to limit the transmission of light transversely to the fitting. The shape of this part of the reflector cross section is known from textbooks and from pending Danish patent application No. 5775/76.
However, between these two parts of the reflector cross section there is inserted a straight part, or an approximately straight part, from that point on the involute curve to the light source cross section in the same plane, from which a half-tangent to the light source is parallel--for symmetrical reflectors--to the plane of symmetry.
This straight part in the reflector cross section continues so far that the light intensity in directions near the reflector's plane of symmetry is so much less than the intensity of light at greater angles from the plane of symmetry that the light transmission results in a focal point relationship which, according to the BZ system, is greater than 0.7 at S/Hm=1.5.
Therefore, there is no real continuity in the transition between the types of curves used, and several of the remaining characteristics displayed in the shaping of the reflector according to Danish patent application No. 5775/76 do not apply to the reflector as described here.
The reflector system according to the invention will, however, display optimum characteristics with regard to energy loss, outer dimensions and glare, and also the improvement in the application possibilities which lies in the fact that it will provide good regularity in the illumination, even when the light fittings hang spread with S/Hm=1.5.
This improvement is necessary for the reason that the regularity of the illumination must not be diminished in the mounting of reflectors on existing installations.
Reflectors of the above-mentioned shape are difficult to mount in existing fittings which do not already have reflectors, and on completely freely-disposed fluorescent tubes.
The object of the invention is to provide a reflector system consisting of a reflector of the correct shape, for example of anodized aluminium plate, which is cheap to produce, and also to provide securing elements which are similarly simple and thus also cheap to produce. Moreover, with lighting installations, it is important that after having been fitted with reflectors that the installation maintains a reasonable
REFERENCES:
patent: 1903985 (1933-04-01), De Sherbinin
patent: 2103322 (1937-12-01), De Sherbinin
patent: 2300915 (1942-11-01), Florence
patent: 2304445 (1942-12-01), Doane
patent: 2434440 (1948-01-01), Schafranek
patent: 2446461 (1948-08-01), Diver
patent: 2524173 (1950-10-01), Peterson
patent: 2741694 (1956-04-01), Thomstad et al.
patent: 2759097 (1956-08-01), Kornan et al.
patent: 4214688 (1980-07-01), Griffin
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