Gm Global Technolgoy Operations, Inc.

Nancy Jean Paulus

Richard W Duce

Robert Gregory Fournier

Sara Ann Touse-Shunkwiler

Venkatesh Rajagopalan

William John Paulus

Kathryn Mary McCauley

David K Chen

Earl Wayne Lankheet

Raymond E Bedford

Kurt W Wright

David A Thompson

Terrence B Boyer

John J Sterba

A sensor with a glass seal between a planar sensing element in a tubular housing and the tubular housing, wherein the glass seal is maintained in radial compression over an entire temperature operating range of the sensor. The compressed seal has improved strength and durability, is self-limiting and is operable over a large temperature range and in an environment subject to jarring and vibrations.

Sensor with glass seal

The invention includes the use of a pre-equilibration zone on an exhaust gas sensor to provide catalytic site to catalyze non-reacted components of the exhaust gas prior to the gas sample reaching the sensor's outer electrode. The pre-equilibration zone has microcomposite which preferably includes a precious metal in a porous carrier such as a ceramic oxide. The invention also includes a method of making an exhaust sensor including a pre-equilibration zone, and a method of sampling an exhaust gas by passing the same through a pre-equilibration zone.

Catalytic/ceramic oxide microcomposites for use as exhaust sensor

The invention includes a metal substrate having an insulative coating thereon, wherein the insulative coating is prepared from a composition including .gamma.-alumina (gamma alumina) with a wide particle size distribution that includes at least 10 percent of the particles having by weight being larger than 20 micrometers, 5 to 10 percent by weight pseudo-boehmite, and a catalyst. The composition is sprayed onto the metal substrate at a distance from about 12 to about 15 inches using a round orifice spray nozzle operated at a pressure ranging from about 15 to about 25 psi. A polyvinyl alcohol overcoat is applied to the insulative coating to prevent flaking and chipping when coated metal substrate are stacked on each other. The insulative coating is particularly useful on folded foils used to construct metal monoliths for electrically heating catalytic converters.

Metal substrate with insulative coating thereon and method of making the

The invention includes a flat plate exhaust sensor including a flat plate sensing element which is carried by a first ceramic insulator having at its upper end an upwardly extending annular ring. The annular ring defines a disc-shaped recess which is filled with a glass seal. Thus, the glass seal extends from the flat plate sensor to the annular ring of the ceramic insulator. The sensor includes an upper tubular shell which includes at the lower end a leg portion which extends inside an inner wall of a lower tubular shell. The leg portion includes a foot which is bent to match an outwardly extending sloped annular shoulder formed on an upper insulator. The upper insulator is seated on the glass seal. An intermediate gasket is formed by an active metal braze gasket between the foot and the outwardly extending sloped annular shoulder of the upper insulator. An external seal is provided by a braze ring which joins an upper end of the lower tubular shell to the upper tubular shell. The system removed the thermal expansion mismatch problems of prior art glass seal sensors.

Flat plate sensor with a robust package design

Growing community of inventors

Grand Blanc, MI, United States of America

Nancy Jean Paulus