Patent US4570946A successfully refreshed from Google Patents.
US4570946A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nitrided piston ring with outer layer on surface
Assignee: Nippon Piston Ring Co Ltd
•
Filing: 1985-02-27
•
Granted: 1986-02-18
•
Expires: 2005-02-27
Abstract
Abstract A piston ring provided with a nitriding layer at entire surfaces of the piston ring body to form a compound layer and a diffusion layer, so that a compound layer is formed over the diffusion layer. From an outer peripheral surface of the piston ring body, the compound layer or both compound layer and diffusion layers is removed, and the plating or spraying layer is formed on the exposed diffusion layer or the exposed surface of the piston ring body.
Inventors
- 👤 Takeshi Tsuchiya
- 👤 Shuji Samejima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:11
CPC Classifications
C; C23; C23C; C23C4/00; C23C4/02; C23C8/00; C23C8/80; F; F16; F16J; F16J9/00; F16J9/26
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
75 words
A piston ring comprising; a piston ring body formed of one of steel and cast iron; nitriding layer formed over said ring body surfaces, said nitriding layer including a diffusion layer and a compound layer provided over said diffusion layer; at the outer peripheral portion of said piston ring body, at least said compound layer being removed; and one of plating and spraying layer formed on the outer peripheral surface of said piston ring body.
Claim 2
Dependent Claim
75 words
A piston ring comprising; a piston ring body formed of one of steel and cast iron; nitriding layer formed over said ring body surfaces, said nitriding layer including a diffusion layer and a compound layer provided over said diffusion layer; at the outer peripheral portion of said piston ring body, at least said compound layer being removed; and one of plating and spraying layer formed on the outer peripheral surface of said piston ring body.
Claim 3
Dependent Claim
36 words
A piston ring of claim 1, wherein said outer peripheral portion of said piston ring body is provided with diffusion layer only, and said one of plating and spraying layer is formed on said diffusion layer.
Claim 4
Dependent Claim
26 words
A piston ring of claim 1, wherein said one of plating and spraying layer is formed directly on said outer peripheral surface of said ring body.
Claim 5
Dependent Claim
13 words
A piston ring of claim 1, wherein said plating is formed of chromium.
Claim 6
Dependent Claim
21 words
A piston ring of claim 1, wherein said plating is formed of a disperation of discrete particles within a plated matrix.
Claim 7
Dependent Claim
15 words
A piston ring of claim 1, wherein said spraying layer is formed of ferrous material.
Claim 8
Dependent Claim
14 words
A piston ring of claim 1, wherein said spraying layer is formed of molybdenum.
Claim 9
Independent Claim
80 words
A method for producing a piston ring comprising: the steps of preparing a piston ring body formed of one of steel and cast iron; forming nitriding layer at entire surfaces of said ring body to form an internal diffusion layer and a compound layer; removing at least said compound layer from said nitriding layer on an outer peripheral portion of said ring body; forming one of plating and spraying layer on the exposed outer peripheral surface of said ring body.
Claim 10
Independent Claim
80 words
A method for producing a piston ring comprising: the steps of preparing a piston ring body formed of one of steel and cast iron; forming nitriding layer at entire surfaces of said ring body to form an internal diffusion layer and a compound layer; removing at least said compound layer from said nitriding layer on an outer peripheral portion of said ring body; forming one of plating and spraying layer on the exposed outer peripheral surface of said ring body.
Claim 11
Dependent Claim
27 words
A method of claim 8, wherein both said compound and diffusion layer are removed from said nitriding layer on the outer peripheral surface of said ring body.
References Cited (Backward Citations)
GB662213A
Cited
US2905512A
Cited
DE1195110B
Cited
GB1057570A
Cited
DE2934027A1
Cited
US4299401A
Cited
US4407515A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-17 | 1989-08-19 | 1990-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-17 | 1993-08-19 | 1994-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-17 | 1997-08-19 | 1998-02-18 | $7700.00 | Window Closed / Lapsed |