Hermetic glass-to-metal seal useful in headers for airbags
AssigneeCoors Ceramics Company
InventorsRobert E. Naugler, Frank E. Anderson
Life of this patent
Estimating the term…
Abstract
A hermetic glass-to-metal seal between a conductive pin and an outer body, wherein a corrosion-resistant noble metal (e.g., gold) coating is applied to the conductive pin before the hermetic seal is formed. The noble metal-coated conductive pin is located in glass having a softening point less than about 650° C. and disposed in a cavity of the outer body. This is accomplished by inserting the coated conductive pin into a bore in a glass preform, heating the assembly to a temperature in excess of the softening point of the glass but less than about 700° C., and cooling the assembly. The coefficients of thermal expansion of the components of the assembly are preferably selected such that the resulting assembly is a hermetic compression seal.
Claims16
An article having a compression glass-to-metal seal, the article being adapted for use on a header for an air bag and the article comprising;
- (a) an outer body having a single cavity extending therethrough the cavity having therein a single conductive pin and fused glass;
- (b) the single conductive pin having an outer surface and having a layer of noble metal coated over substantially all of said outer surface, said pin extending through said cavity and having one end protruding from the outer body and the fused glass;
- said pin having a coefficient of thermal expansion;
- and
- (c) the fused glass originating from a unitary fused glass preform with a bore therethrough for receiving the single pin and being disposed within and extending completely across said cavity to form a substantially hermetic compression seal between said pin and said outer body, wherein said fused glass preform has a softening point of less than about 650° C. and wherein said outer body has a coefficient of thermal expansion greater than the coefficient of thermal expansion of said glass.
An article having a glass-to-metal compression seal and adapted for use as a header for an air bag, the article comprising:
- (a) a metal outer body having a single cavity extending therethrough, the cavity having therein a single conductor pin and fused glass;
- (b) the single conductive metal pin having an outer surface and having a layer of gold coated over substantially all of said outer surface, said coated metal pin extending through said cavity and having one end protruding from the outer body and the fused glass;
- and
- (c) the fused glass originating from a unitary fused glass preform with a bore therethrough for receiving the single pin and being disposed within said cavity to form a substantially hermetic compression seal between said pin and said outer body, wherein said fused glass preform has a coefficient of thermal expansion that is at least about 10×10−7 per ° C. less than the coefficient of thermal expansion of said outer body and a softening point of less than about 650° C.
Dependencies are inferred from the claim text.