GB542246A - Improvements in or relating to lighting and sterilizing apparatus - Google Patents

Abstract

542,246. Supporting lamps. SHEPHERD, G. R. (Westinghouse Electric International Co.). July 8, 1940, No. 11395. [Classes 75 (iii) and 75 (iv)] [Also in Group VI] Lighting apparatus, particularly for use in hospital operating rooms, has means for generating ultra-violet radiations arranged in conjunction with the lumination lamp; regulating means are provided so that the intensity of the ultraviolet radiations are maintained at a constant value on the patient on the operating table whatever be the position of the lamp. The lamp unit is shown in Fig. 1 suspended, above the operating table 4, from the ceiling support 6 in which it is rotatable. The hanging member 5 supports a bifurcated member 7 in which is pivoted a shaft 9 carrying the lamp unit in a bifurcation at one end and a counter-weight 12 at the other. The lamp unit consists of a spider 16 and a framework 14 of a truncated conical form carrying a number of inclined trapezoidal mirrors 15; the lamp is arranged at the centre at the focus of an annular Fresnel lens. A control knob 17 protrudes from the counter-weight 12 and by means of suitable mechanism enables the shaft 9 and the lamp unit to be swung into various positions about their supports, while the lower periphery of the lamp unit is maintained parallel to the table. The unit is provided with two semi-circular ultra violet lamps 18 arranged at the periphery in a reflecting section formed by the curved lower part 19 of the frame 14, and a parabolic section 20. The ultra-violet lamps 18 are connected to the supply through a transformer 24 and rheostats 25, 36. The latter 36 can be set so that a pre-selected maximum violet ray intensity cannot be exceeded. The former 25 is automatically varied as the position of the lamp unit is varied. A housing 22 is carried by the member 7 and encloses the transformer 24. A shaft 27 with a control knob 28 protrudes from the housing and carries a pinion 29 meshing with a rack bar 30 pivoted to a link bar 33 secured to the yoke 21 by a nut and bolt arrangement 34 which can be adjusted in the slot 35. By means of this adjustment the rheostat 36 is set and the nut 34 tightened to maintain its position. The set-screw 37 is loosened and control knob 28 is manipulated to set the rheostat 25 to an appropriate value corresponding to the position of the lamp and the set screw is then tightened. Thereafter the rheostat 25 is adjusted automatically when the lamp unit is moved. In a modification the adjustment is effected hydraulically.