US2257419A - Lighting fixture - Google Patents

Description

Sept. 30, "1941. F, w, A, KURZ 2,257,419

LIGHTING FIXTURE Filed Feb. 14, 1940 flew, an)? Patented Sept. 30, 1941 LIGHTING FIXTURE Friedrich Wilhelm Anton Kurz, Orrcfors, Sweden, assignor to Aktiebolaget Orrefors Glasbruk, Orrefors, Sweden, a corporation of Sweden Application February 14, 1940, Serial No. 318,953 In Sweden March 14, 1939 1 Claim.

The present invention relates to lighting fixtures of the type comprising a shade surrounding the source of light and a reflector located above the said shade. The object of the invention is to provide a perfectly non-dazzling lighting fixture of the type indicated having the greatest possible efficiency.

In previously known lighting fixtures of the general type to which the present invention relates, a substantially horizontal connecting surface of clear glass was inserted, for constructional reasons, in the plane of the source of light between the reflector and the translucent or partly translucent and partly transparent lower portion of the shade. However, since most of the rays reflected by the reflector are thrown upon said connecting surface at acute angles, losses due to refraction and disturbing reflexes will be encountered with the construction indicated. In a lighting fixture devised in accordance with the invention, there is no such horizontal surface, and instead thereof, the rays of light pass through the upper portion of the shade, which has cup-shaped or more or less inclined transparent surfaces, without noticeable losses and disturbing reflexes.

In the annexed drawing, several embodiments of the invention are illustrated in vertical central section.

In the drawing:

Fig. 1 is a section through one embodiment of the invention, showing an incandescent lamp, a shade for said lamp, and an appertaining reflector;

Fig. 2 is a similar view of a slightly modified construction;

Fig. 3 is a further modification of the lighting fixture shown in Fig. 1.

Referring to Fig. 1, reference numeral It indicates the shade which surrounds the source of light H. Above the shade there is removably mounted a reflector l2. As will be obvious, the reflector may be of any suitable shape, such as slightly bulgy, parabolic, hemispherical, cylindrical or conical. In accordance with the desired distribution of light, the reflector may consist of glass, metal or other reflecting material.

The upper portion I3 of the shade consists of clear glass or other transparent substance indicated by double thin lines and is substantially hemispherical in shape with the light source approximately at the center thereof The portion of the shade located below the horizontal plane through the source of light consists of zone I 4 and cup shaped portion 15 of translucent glass indicated by thick lines and of a frusto-conical portion 15 of clear glass or other transparent substance marked by double thin lines.

The portions I4 and I5 which may consist of opal glass, etched glass, frosted glass, coloured glass, enamelled glass or similar translucent material, are separated from each other by the portion [6 of clear glass. The portion I6 is inclined inwardly towards the central axis of the incandescent body and is disposed in such a manner that the rays of light from the lamp cannot directly escape through the portion l6, whereas reflected light can freely pass therethrough. In the embodiment shown in Fig. l, the lower portion of the translucent material is slightly cupshaped. Since between the lower edge of the reflector I2 and the shade there is only an air space, the rays reflected by the reflector will not meet any obstacle on the side of the shade.

The construction shown in Fig. 2 is provided with a reflector l2a of somewhat modified shape. Further, the bottom of the shade consists of a corrugated surface l5a of a material, such as frosted glass, with greater light transparency than the translucent portions l4 and [5. The shade shown in Fig. 3 comprises two inwardly inclined surfaces It and Ilia of clear glass being located such as to prevent direct escape therethrough of the rays from the source of light. In this embodiment, three translucent portions l4, Ila, l5 are provided, said portions being separated from each other by the transparent portions l6 and Ilia.

The scope of the invention is not limited to i the embodiments illustrated in the drawing, but comprises also such constructional modifications as will be embraced by the claim and consistent with the state of the prior art.

What I claim is:

A lighting fixture comprising a unitary glass shade surrounding a light source and a concave uniformly curved reflector mounted above said shade and light source with the lower edge thereof terminating substantially in a horizontal plane passing through the light source, said shade comprising a substantially hemispherical upper portion of clear glass above the horizontal plane through the light source with the light source at the approximate center thereof whereby the light rays pass therethrough to the reflector without refraction or reflection, a zone of translucent glass extending below said horizontal plane through the light source and formed as a continuation of the hemispherical wall of said upper portion, a cup shaped translucent portion centered below said light source, and a frustoconical wall of clear glass joining the rim of the cup to the lower rim of said translucent zone and disposed so that reflected light only can pass therethrough.

FRIEDRICH WILHELM ANTON KURZ.

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