| 摘要 |
1493506 Lamp reflectors SIEMENS AG 9 April 1975 [10 April 1974] 14712/75 Heading F4R A reflector arrangement for a lamp with variable geometry, e.g. to allow changes in the light distribution curve of a street lamp according to the type of road surface and wet or dry conditions, comprises two fixed reflector elements 301, 302 facing one another to define edges of a light exit, and two pivotable reflector elements 303, 304. In one arrangement, as shown, the pivotable elements are hinged at the top of the fixed elements and are equal in length thereto. In other arrangements the pivotable elements are made as hinged flaps in cut-out portions of the fixed elements (Figs. 4, 6, not shown). Both the fixed and pivotable elements may comprise a plurality of angularly disposed planar sections instead of the curved sections shown (Figs. 5-7, not shown). The top 305 of the reflector arrangement is a separate fixed member and has a diffuse reflector surface but in another embodiment the side walls and top are formed as an integral unit with planar sections dimensioned to approximate to a parabola portion in lateral cross-section (Figs. 8a-8b, not shown). Hinged flaps within the widewalls constitute the pivotable elements. |
