| 摘要 |
450,498. Street lamps; reflectors. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London. Aug. 21, 1935, No. 23494. Convention date, Aug. 24, 1934. [Classes 75 (ii) and 75 (iv)] In a street lamp with a horizontally arranged elongated lamp 6 such as a sodium vapour discharge lamp, a pair of reflecting surfaces 15, 16 converging to a ridge 25 parallel to the lamp are arranged to distribute light from the lamp in opposite directions on to a roadway, a pair of reflectors 12, 13 suspended from the convergent reflectors are arranged on opposite sides of and parallel to the lamp, and a plane reflector 14 is arranged at one end of and perpendicularly to the lamp 6. The reflecting surfaces 15, 16 are parts of parabolic cylinders, the focal lines of which coincide with the light source. The curvature of the surfaces 15, 16 is modified near the ridge 25. At the front the surfaces 15, 16 are joined by a paraboidal surface 22. The reflectors 12, 13 may be flat or curved, and have extensions 28, 29. |
