Abstract: A robust coiled filament electrode for a fluorescent lamp used in high vibration environments. A cylindrical mandrel is placed within coils in each end of a coiled filament electrode. The mandrel and the coiled filament electrode are held by a mounting post. The mounting post is bent over and crimped, holding the mandrel and coiled filament electrode. The mandrel extends inward between the two mounting posts, providing support for the coiled filament electrodes. The coiled filament electrode may be made by method or process of chemically dissolving selected portions of a mandrel. Lamp life is extended, as well as the variance between lamp life is substantially reduced. The present invention is particularly applicable to applications in avionics.

Abstract: A method of assembling the arc tube of a high-pressure sodium lamp is disclosed that comprises using a spring clip to engage the lead wire proximate the end plug on the side opposite the electrode coil assembly. The electrode coil assembly is thereby centered relative to the end plug and the three ends of the clip provide planar support of the end plug/electrode on the end of the arc tube. The clip is formed by bending a refractory metal wire 180.degree. about the midpoint, bending the ends of the legs away from each other while maintaining co-planar geometry, and providing an indentation for engaging the lead wire.

Abstract: A high-intensity discharge lamp having an arc tube which is enclosed by and supported within a light-transmitting outer envelope which is spaced from the arc tube. The outer envelope enclosing a hard vacuum. Electrical lead-in means are sealed through the arc tube connected to the electrodes. Electrical adapter means are affixed to the outer surface of the protective envelope to facilitate electrical connection for the lamp to a source of electrical power. A pair of electrical conductors electrically connect the electrical adapter means to the electrical lead-in means. Fuse means is provided. The fuse means has a fusible element extending from one of the electrical conductors and separated from and encircling an insulating sleeve means carried about the other of the electrical conductors, so that the spacing therebetween constitutes the shortest gap within the envelope between opposite current-carrying components. The hard vacuum enclosed by the outer envelope is obtained by flashing barium getter means.