Filament support for incandescent lamps.

摘要

An incandescent lamp (54) containing a coiled filament (28) within a vitreous envelope wherein the filament is supported at at least one point along its coil length by a refractory metal support wire (10) one end of which is welded to a coil (28) and the other end secured to the envelope wall by a glass bead (24). The support prevents filament sag during lamp operation and is especially useful with double-ended high intensity tungsten-halogen lamps having an elliptically shaped filament chamber with an infrared reflecting and visible light transmitting optical interference coating on the chamber. <IMAGE>