Patent US3673452A successfully refreshed from Google Patents.
US3673452A
Expired / Lapsed
US
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Spark plug
Assignee: Individual
•
Filing: 1970-09-21
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Granted: 1972-06-27
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Expires: 1990-09-21
Abstract
Abstract A spark plug for a combustion engine or a combustion chamber, in which the electrodes of ferrous metals or ferroalloys have a coating fused directly thereon by a process known in the art as ''''electronic sputtering.'''' The coating forms a very thin laminar deposit of a high temperature resistant metal, for example, one of the carbides of tungsten, titanium and chromium.
Inventors
- 👤 Ronald F Brennen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:53
CPC Classifications
H; H01; H01T; H01T13/00; H01T13/20; H01T13/39
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
46 words
A spark plug for a combustion engine or combustion chamber having a pair of spaced electrodes exposed to high operating temperatures, said electrodes having thereon a coating of a high temperature resistant material selected from the group consisting of the carbides of tungsten, titanium and chromium.
Claim 2
Dependent Claim
46 words
A spark plug for a combustion engine or combustion chamber having a pair of spaced electrodes exposed to high operating temperatures, said electrodes having thereon a coating of a high temperature resistant material selected from the group consisting of the carbides of tungsten, titanium and chromium.
Claim 3
Dependent Claim
39 words
A spark plug for a combustion engine or combustion chamber as defined in claim 1, in which the high temperature resistant material is deposited as a very thin coating only on the portions of the electrodes facing each other.
Claim 4
Dependent Claim
29 words
A spark plug for a combustion engine or combustion chamber as defined in claim 4, in which the thickness of the coating is not in excess of 0.002 inch.
Claim 5
Dependent Claim
26 words
A spark plug for a combustion engine or combustion chamber as defined in claim 1, in which the coating is deposited by an ''''electronic sputtering'''' process.
Claim 6
Dependent Claim
33 words
A spark plug for a combustion engine or a combustion chamber as defined in claim 1, in which the electrodes are selected from the group consisting of a ferrous metal and a ferroalloy.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |