Patent US78988A successfully refreshed from Google Patents.
US3833320A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coating for apex seals of rotary engines and method of making
Assignee: Ford Motor Co
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Filing: 1973-07-05
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Granted: 1974-09-03
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Expires: 1993-07-05
Abstract
Abstract A rotary internal combustion engine is disclosed having a rotor housing presenting an internal epitrochoid surface electrolytically coated with a composite of nickel and silicon carbide or coated with tungsten carbide. A rotor piston is mounted for planetary movement within the rotor housing and carries a plurality of apex seal strips each comprised of a wearresistant portion and a supporting portion. The wear-resistant portion is constituted of a fused composite of generally equally hard particle types, one type comprising martensitic stainless steel and the other particle type comprising a nickel-based alloy. At least one of the particle types contains molybdenum disulfide or graphite. An intermediate coating of nickel aluminide may preferably be used therebetween. The supporting portion is constituted of a material having a lower specific gravity than the wear-resistant portion and a greater yield strength. The supporting portion may be preferably comprised of aluminum.
Inventors
- 👤 Y Telang
- 👤 J Uy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:11
CPC Classifications
F; F01; F01C; F01C19/00; F01C19/005
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
150 words
A seal element for use on a rotor subjected to planetary motion within a rotary engine, said element being subjected to increasing and decreasing radially directed inertial forces during each revolution of said rotor and said rotor carrying means for countering said inertial forces to continuously maintain engagement of said seal element with an outer housing, said seal element comprising: a. a supporting strip of material having an elongated configuration effective to extend substantially transversely across said rotor at predetermined circumferential locations thereof, said supporting strip being formed from material having a specific gravity no greater than 7.5, b. an outer wear-resistant coating comprising an alloy of chromium, nickel and boron held together by a metal binder, said alloy and binder being deposited by thermal spraying upon said supporting strip to a thickness in the range of 15-20 mils, said coating having a porosity in the range of 5-8 percent.
Claim 2
Dependent Claim
150 words
A seal element for use on a rotor subjected to planetary motion within a rotary engine, said element being subjected to increasing and decreasing radially directed inertial forces during each revolution of said rotor and said rotor carrying means for countering said inertial forces to continuously maintain engagement of said seal element with an outer housing, said seal element comprising: a. a supporting strip of material having an elongated configuration effective to extend substantially transversely across said rotor at predetermined circumferential locations thereof, said supporting strip being formed from material having a specific gravity no greater than 7.5, b. an outer wear-resistant coating comprising an alloy of chromium, nickel and boron held together by a metal binder, said alloy and binder being deposited by thermal spraying upon said supporting strip to a thickness in the range of 15-20 mils, said coating having a porosity in the range of 5-8 percent.
Claim 3
Dependent Claim
47 words
The seal element as in claim 1, in which an intermediate coating of nickel aluminide is sprayed upon the supporting body in a thickness range of 5-8 mils, and said outer wear-resistant coating is mechanically removed after deposition to result in a thickness range of 10-12 mils.
Claim 4
Dependent Claim
152 words
A rotatable body member and seal combination for use within a hollow outer body, said bodies defining a combustion chamber for a rotary engine, the combination comprising: a. a rotatable body member presenting more than one apex for dividing the space of said chamber, each apex having a slot for carrying one of said seals, b. a seal formed as an elongated strip fitting loosely within said slot and effective to be sequentially urged by gases within said combustion chamber against respective opposite sides of said slot during a complete revolution of the body member, said seal having an adherent wear-resistant portion, consisting of a self-fused composite of generally equally hard particle types, one type comprising martensitic stainless steel and the other particle type comprising a nickel-based alloy, at least one of the particle types having an addition of 2-5 percent by weight of an element selected from molybdenum disulfide or graphite.
Claim 5
Dependent Claim
152 words
A rotatable body member and seal combination for use within a hollow outer body, said bodies defining a combustion chamber for a rotary engine, the combination comprising: a. a rotatable body member presenting more than one apex for dividing the space of said chamber, each apex having a slot for carrying one of said seals, b. a seal formed as an elongated strip fitting loosely within said slot and effective to be sequentially urged by gases within said combustion chamber against respective opposite sides of said slot during a complete revolution of the body member, said seal having an adherent wear-resistant portion, consisting of a self-fused composite of generally equally hard particle types, one type comprising martensitic stainless steel and the other particle type comprising a nickel-based alloy, at least one of the particle types having an addition of 2-5 percent by weight of an element selected from molybdenum disulfide or graphite.
Claim 6
Dependent Claim
15 words
The combination as in claim 3, in which the martensitic stainless steel is type 420.
Claim 7
Dependent Claim
25 words
The combination of claim 3, in which the composite chemical analysis of the wear-resistant portion contains at least 40 percent iron and 35 percent nickel.
Claim 8
Dependent Claim
17 words
The combination as in claim 3, in which the wear-resistant portion has a porosity of 5-8 percent.
Claim 9
Dependent Claim
33 words
The combination as in claim 3, in which the strip supporting said wear-resistant portion is comprised of a material having a lower specific gravity and a higher yield strength than said wear-resistant portion.
Claim 10
Dependent Claim
32 words
The combination as in claim 3, in which said wear-resistant portion has an arcuate face presented for engagement with the hollow outer body, said wear-resistant portion being metallurgically bonded to said strip.
Claim 11
Dependent Claim
25 words
The combination as in claim 3, in which said nickel-basEd alloy further comprises about 5 percent silicon, about 3.0 boron and about 0.5 percent carbon.
Claim 12
Dependent Claim
20 words
The combination as in claim 9, in which said nickel-based alloy preferably is comprised of chromium of about 13 percent.
Claim 13
Dependent Claim
26 words
The combination as in claim 3, in which the supporting seal strip is comprised of a material having a specific gravity less than said wear-resistant portion.
Claim 14
Dependent Claim
26 words
The combination as in claim 3, in which said nickel-based alloy comprises about 5 percent iron, 1-3 percent boron, and 1.5-3.5 percent silicon, the remainder nickel.
Claim 15
Dependent Claim
15 words
The combination as in claim 12, in which said nickel-based alloy contains 10-17 percent chromium.
Claim 16
Dependent Claim
124 words
The combination as in claim 3, in which the hollow body has an end wall defining an epitrochoid and said rotatable body member is effective to move through a planetary motion with said seals in continuous engagement with said epitrochoid surface, each of said seal strips extending generally parallel to the axis of rotation of said body member and substantially across the entire transverse extent of the hollow body, said seal strips being subjected to increasing and decreasing inertial forces during each revolution of said body member and subjected to a mechanical bias force to maintain engagement with said end wall, said wear-resistant portion cooperating with the material of said end wall to increase the integrity and consistency of contact with said end wall.
Claim 17
Dependent Claim
27 words
The combination as in claim 14, in which the radial inertial forces acting on said seal strip exceed 200 pounds during eavh revolution of the rotatable member.
Claim 18
Dependent Claim
30 words
The combination as in claim 3, in which the supporting seal strip is constituted of a material selected from the group consisting of cast iron, aluminum and plain carbon steel.
Claim 19
Dependent Claim
22 words
The combination as in claim 16, in which a coating of nickel aluminide is interposed between said wear-resistant portion and supporting strip.
Claim 20
Dependent Claim
27 words
The combination as in claim 16, in which the intermediate coating has a thickness between 5-8 mils and the wear-resistant portion has a thickness between 15-20 mils.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-02 | 1978-03-04 | 1978-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-02 | 1982-03-04 | 1982-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-02 | 1986-03-04 | 1986-09-03 | $7700.00 | Window Closed / Lapsed |