GB714761A - Improvements to electric lamps - Google Patents

Abstract

714,761. Filament supports for electric lamps. CAMILLBRAPP, M. M. April 30, 1951 [Sept. 27, 1950 ; Jan. 20, 1951], No. 10127/51. Class 39 (2) In order to obviate the effect of vibration or mechanical shock upon the filament of an electric incandescent lamp, the filament 6 is attached to rigid arms 16, 17, and radial supporting wires 5 secured to an insulating arbor 1 and forming a unit which is mounted on one end of at least three flexible metal rods 10-12, at least two of which serve as current leads to the filament. The three flexible supporting rods 10-12 are sealed into the pinch 13 at their lower ends and, in the example, the upper ends of the rods 10 and 11 are clamped or welded to filament mounting arms 16, 17 extending radially from the arbor 11 whilst the wire 12 functions as a damping wire which is welded to a radial wire 22. The current conducting rods 10, 11 may be made of tantalum or molybdenum or, in the case of gas-filled lamps, of nickel plated or chromeplated steel, these rods being resilient, and the damping rod 12 made of pure copper which has been annealed. Intermediate their ends the rods 10-12 are welded to radial arms 18, 19, 21 sealed into a bead 20 on the arbor 1. Instead of being straight the rods 10-12 may be in the form of a zigzag or a helix, and the damping rod 12 may be connected to a point on the filament and comprise a current conductor if the filament is to be fed with polyphase current or is divided into two parts which may be of different resistances.