US4205649A
Expired / Lapsed
US
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Light-metal piston
Assignee: Mahle GmbH
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Filing: 1977-06-06
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Granted: 1980-06-03
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Expires: 1997-06-06
Abstract
Abstract A light-metal piston with parts hard-eloxated to increase their resistance to heat and mechanically reinforced to the depth of the hard eloxation.
Inventors
- 👤 Albrecht Ostermann
- 👤 Manfred Rohrle
- 👤 Klaus Welker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:59
CPC Classifications
F; F16; F16J; F16J1/00; F16J1/01; F02; F02F; F02F3/00; F05; F05C; F05C2201/00; F05C2201/02; F05C2201/021; F05C2251/00; F05C2251/04; F05C2251/042; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49249; Y10T29/49256; Y10T29/49263
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
80 words
A light metal piston for a combustion engine, said piston having a combustion cavity including an edge, only said edge being eloxated to provide a coating of eloxated material in the zone at and adjacent to said edge, and only that zone of the piston being subsequently compressed after eloxation in such a manner that the depth of the compressed effect is approximately the same as the depth of the eloxated material, this depth being between 40 and 150 μm.
Claim 2
Dependent Claim
80 words
A light metal piston for a combustion engine, said piston having a combustion cavity including an edge, only said edge being eloxated to provide a coating of eloxated material in the zone at and adjacent to said edge, and only that zone of the piston being subsequently compressed after eloxation in such a manner that the depth of the compressed effect is approximately the same as the depth of the eloxated material, this depth being between 40 and 150 μm.
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) | 1983-06-03 | 1983-12-03 | 1984-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-06-03 | 1987-12-03 | 1988-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-06-03 | 1991-12-03 | 1992-06-03 | $7700.00 | Window Closed / Lapsed |