Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh

Helmut Grahmann

Rolf Kiesel

Horst Wittmann

Dieter Hofmann

Alfred Wacker

Gerhard Maier

To eliminate the necessity for a temperature-hardening cement to set the ular ends of paired discharge tubes into a plastic base, a holding element (7), including inwardly and downwardly directed barbs or tongues (8), is located within the base, the barbs or tongues engaging in depressions (3) or behind projections (3') of the pinch seal (2) normally formed at the end of the tubes. To additionally hold the tubes in position, a compression gasket (9) is interposed between a cover cap (6) and the bottom portion (5) of the base, the cover cap and the bottom portion being connected together by a snap fit.

Single-ended fluorescent discharge lamp construction

The lamp has a pinch seal which surrounds a mounting structure carrying l-in wires of the filament;

Electric lamp with an envelope seal designed as pinch seal, and a device

To permit the use of hard glass rather than silica or quartz glass, a bulb of hard glass is drawn from a length of hard glass tubing, the exhaust tube being molded on adjacent the rounded-off bulb. A mount assembly composed of filaments and two or more lead-in wires is pinch-sealed into the bulb such that pre-oxidized portions of the lead-in wires come to lie within the pinch seal. The pinch seal is rendered vacuum-tight and shaped in separate steps including repeated heating to fuse the wires to the glass and to shape the pinch seal. Subsequent to filling with inert gas, the lamp manufacture is terminated by tipping off the exhaust tube.

Growing community of inventors

Friedberg, Germany

Helmut Grahmann