Patent US4968045A successfully refreshed from Google Patents.
US4968045A
Expired / Lapsed
US
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Metal gasket
Assignee: Nippon Leakless Industry Co Ltd
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Filing: 1988-11-22
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Granted: 1990-11-06
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Expires: 2008-11-22
Abstract
Abstract A metal gasket for an internal combustion engine has cylinder openings and a cooling water openings and is coated on its outer surface with a surface treatment agent. The surface treatment agent in a region of the metal gasket surrounding the cooling water openings has been removed. A method of producing a metal gasket having at least a cooling water opening comprises steps of coating a surface treatment agent on an outer surface of the metal gasket, covering by a masking jig the outer surface of the metal gasket except a region surrounding the cooling water opening, and removing the surface treatment agent in the region by jetting superhigh pressure water at the region.
Inventors
- 👤 Tsunehiko Abe
- 👤 Sadao Watanabe
- 👤 Norio Hamba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:13
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/02; F16J15/06; F16J15/08; F16J15/0818; F16J15/0825; F16J2015/085; F16J2015/0856
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
101 words
A metal gasket for an internal combustion engine having at least one cylinder opening and at least one cooling water opening, said metal gasket comprising a metal sheet having opposed outer surfaces and a permanent non-metal, surface treatment agent covering said outer surfaces in direct contact with said metal sheet, a region of said metal sheet adjacent to and surrounding said cooling water opening being free from said surface treatment agent, a substantial portion of the region free from said surface treatment agent extending away from said cooling water opening a distance greater than the diameter of said cooling water opening.
Claim 2
Dependent Claim
101 words
A metal gasket for an internal combustion engine having at least one cylinder opening and at least one cooling water opening, said metal gasket comprising a metal sheet having opposed outer surfaces and a permanent non-metal, surface treatment agent covering said outer surfaces in direct contact with said metal sheet, a region of said metal sheet adjacent to and surrounding said cooling water opening being free from said surface treatment agent, a substantial portion of the region free from said surface treatment agent extending away from said cooling water opening a distance greater than the diameter of said cooling water opening.
Claim 3
Dependent Claim
22 words
A metal gasket as claimed in claim 1, there being a plurality of said cooling water openings, said region interconnecting said openings.
Claim 4
Dependent Claim
20 words
A metal gasket as claimed in claim 2, said region being disposed in a closed path encompassing said cylinder opening.
Claim 5
Dependent Claim
24 words
A metal gasket as claimed in claim 3, there being a plurality of cylinder openings, said closed path encompassing all of said cylinder openings.
Claim 6
Dependent Claim
36 words
A metal gasket as claimed in claim 1, having also a plurality of bolt holes therethrough, said surface treatment agent surrounding and extending up to said bolt holes and separating said bolt holes from each other.
Claim 7
Dependent Claim
30 words
A metal gasket as claimed in claim 1, in which said surface treatment agent is a member selected from the group consisting of rubber, synthetic resin, and a mixture thereof.
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) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |