Patent CA576729A successfully refreshed from Google Patents.
Patent US4407515A successfully refreshed from Google Patents.
US4407515A
Expired / Lapsed
US
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Combined oil ring
Assignee: Nippon Piston Ring Co Ltd
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Filing: 1982-06-11
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Granted: 1983-10-04
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Expires: 2002-06-11
Abstract
Abstract A combined oil ring comprising a steel spacer expander and two steel side rails is described, which has excellent wear resistance and can be used in, for example, an internal combustion engine. The spacer expander and the side rail have specific structures procuded by applying a low temperature gas nitriding treatment.
Inventors
- 👤 Yoshio Naito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:33
CPC Classifications
F; F16; F16J; F16J9/00; F16J9/26; F16J9/06; F16J9/064; F16J9/066; F16J9/067; F16J9/12; F16J9/20; F16J9/203
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
59 words
An oil ring, comprising; a steel spacer expander and a pair of steel side rails, said steel spacer expander comprising a parent material of Austenite matrix structure and having a nitride layer in the surface the thereof; said steel side rails comprising a parent material of Martensite matrix structure, and having a nitride layer formed in the surface thereof.
Claim 2
Dependent Claim
59 words
An oil ring, comprising; a steel spacer expander and a pair of steel side rails, said steel spacer expander comprising a parent material of Austenite matrix structure and having a nitride layer in the surface the thereof; said steel side rails comprising a parent material of Martensite matrix structure, and having a nitride layer formed in the surface thereof.
Claim 3
Dependent Claim
22 words
A device as claimed in claim 1, said nitride layer of said steel spacer expander having a thickness of at least 2μ.
Claim 4
Dependent Claim
22 words
A device as claimed in claim 1, said surface of said expander having a total hardness of HV 800 to HV 1,000.
Claim 5
Dependent Claim
24 words
A device as claimed in claim 1, said steel side rails including fine granular carbides dispersed in an area ratio of 3 to 7%.
Claim 6
Dependent Claim
26 words
A device as claimed in claim 4, said carbides having a grain size of 10μ or less and a hardness of HV 1,200 to HV 1,500.
Claim 7
Dependent Claim
36 words
A device as claimed in claim 1, said nitride layer formed on said steel rails having a thickness of at least 2μ, and the surface thereof having a total hardness of HV 900 to HV 1,500.
Claim 8
Dependent Claim
20 words
A device as claimed in claim 1, further including a diffusion layer beneath said nitride layer of said steel rails.
Claim 9
Dependent Claim
17 words
A device as claimed in claim 7, said diffusion layer having a thickness of at least 20μ.
Claim 10
Dependent Claim
26 words
A device as claimed in claim 1, said steel rails containing carbon and chromium in a range of 0.6 to 1.4% and 12 to 19%, respectively.
Claim 11
Dependent Claim
26 words
A device as claimed in claim 1, said steel rails containing molybdenum and vanadium in a range of 1 to 1.3% and 0.07 to 0.12%, respectively.
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) | 1986-10-03 | 1987-04-04 | 1987-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-03 | 1991-04-04 | 1991-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-03 | 1995-04-04 | 1995-10-04 | $7700.00 | Window Closed / Lapsed |