GB464885A - Improvements in and relating to negative glow electric discharge devices - Google Patents

Abstract

464,885. Discharge lamps. HENNINGER, A. F. May 9, 1936, No. 13206. [Class 39 (i)] [Also in Group XVIII] The electrodes of a negative glow device are supported from one or more plates of substantial area which either engage the envelope or are spaced a small distance therefrom and secured to a member, transverse to the plate, which engages the envelope. The plate may be of mica with the electrodes flat against it, or of metal, with the electrodes spaced away from it. In one form, Fig. 3, a plate 13 of mica extends diametrically across a tubular envelope so as to engage it at each edge. An electrode 14, in the shape of a bottle, and an electrode 27 are mounted against the plate. Electrodes 17, 25 and 28 perforated with designs are spaced from the plate by insulating bushings 23 and secured to a lead 18. Further electrodes 32, 35, of desired shape, are furnished with separate leads and supported by the bushings 38. A single plate 13, or a pair back to back, bent so as to engage the envelope firmly may be employed. The electrodes may be employed selectively by a switching mechanism. In a modification, Fig. 8, a metal member 39 carries mica plates 13 which are supported at the end remote from the pinch by a mica disc transverse to them and engaging the envelope. The electrodes 14 are secured to the plates 13 by bent-over tabs 41 which are coated with an insulating varnish. A number of electrodes 14, shaped as letters may be employed on each face, and the tabs 41 of adjacent letters may engage to give electrical contact. A flaming discharge effect is produced in the narrow space B. Shields 45 may be mounted on the plates. A single plate may carry electrodes flat on one face and a single electrode spaced from it with an interposed shield, on the other.