Robert Boschgmbh

Gunther Knoll

Thomas Frey

Helmut Weyl

Werner Grunwald

Friedrich J Esper

Heinz Geier

Gerhard Holfelder

A rod-like electrical heating element is incorporated in the interior of a tubular solid electrolyte sensor connecting zones of the heating element are disposed on the end face thereof remote from the sensing end. Electrical connecting parts are pressed against the connecting zones of the heating element by means of a spring element. These electrical connecting parts are in electrical contact with the connecting cable of the gas sensor via conductor wires, leads or other connecting means.

Gas sensor, particularly oxygen sensor exposed to combustion exhaust

To decrease the preheat time and power requirements in preheater-type glow plugs for Diesel engines, a closed ceramic tube (20), for example of aluminum oxide and of about 5 mm diameter has, on the bottom (21) thereof applied a layer or film-like heater element (24, 24'), for example in an undulating or zig-zag configuration (FIG. 2) or in form of a constriction or pinch (FIG. 4: 24') to provide a concentrated point or strip source of heat. The heater layer itself is protected by a protective coating (25) and, to provide for the required heat distribution, the underlying bottom (21, 21') of the tube (20, 20') supports an insulating intermediate layer and possibly a heat conductive layer is intermediate. Preheat times in the order of 1-2 seconds, with lower current consumption than prior wound-wire plugs can be obtained.

Glow plug, particularly for diesel engine

Growing community of inventors

Stuttgart, Germany

Gunther Knoll