Patent US3850678A successfully refreshed from Google Patents.
Patent US3888746A successfully refreshed from Google Patents.
US3888746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of providing an intermediate steel layer for chrome plating on rotor housings
Assignee: Ford Motor Co
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Filing: 1974-01-04
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Granted: 1975-06-10
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Expires: 1994-01-04
Abstract
Abstract A method (and resulting product) is disclosed for making rotor housings useful in a rotary internal combustion engine. The housing is preferably sand cast; the internal epitrochoid surface is flame-spray coated with a thin layer of nickel-aluminide, flame-spray coated with a thicker layer of plain carbon steel, and then plated with chromium. The resulting casting-coating composite provides enhanced wearability, increased dimensional stability, and reduced internal stress of the coatings.
Inventors
- 👤 James C Uy
- 👤 Yeshwant P Telang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:13
CPC Classifications
F; F01; F01C; F01C21/00; F01C21/10; F01C21/104; F01C21/106; C; C25; C25D; C25D5/00; C25D5/34; C25D5/42; C25D5/44; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49231; Y10T29/49234
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
143 words
A METHOD OF FABRICATING A ROTOR HOUSING FOR A ROTARY INTERNAL COMBUSTION ENGINE, COMPRISING: A. PREPARING AN ALUMINUM CASTING DEFINING SAID ROTOR HOUSING HAVING AN ANNULAR CONFIGURATION WITH AN INTERNAL SURFACE SHAPED AS A TROCHOID, SAID CASTING HAVING DIMENSIONALLY MACHINED SIDES AND A ROUGH AS-CAST TROCHOID SURFACE, SAID CASTING HAVING AT LEAST ONE PASSAGE OPENING INTO SAID SURFACE WHICH IS TEMPORARILY CLOSED BY AN INERT PLUG DURING SUBSEQUENT PROCESSING, B. WITH SAID CASTING MAINTAINED AT A TEMPERATURE OF AT LEAST 200*F, APPLYING A THIN SELF-FUSED COATING OF HEATED NICKELALUMINIDE PARTICLES ACROSS SAID ENTIRE TROCHOID SURFACE TO FORM A LAYER THEREON WITH A THICKNESS NO GREATER THAN 0.01 INCH, C. IMMEDIATELY APPLYING A UNIFORM COATING OF CARBON STEEL PARTICLES HAVING AT LEAST THE OUTER SURFACES THEREOF HEATED TO A TEMPERATURE OF AT LEAST 2,000*F FOR SELF-FUSING WHEN IMPELLED AGAINST SAID FIRST COATED CASTING SURFACE,
Claim 2
Independent Claim
143 words
A METHOD OF FABRICATING A ROTOR HOUSING FOR A ROTARY INTERNAL COMBUSTION ENGINE, COMPRISING: A. PREPARING AN ALUMINUM CASTING DEFINING SAID ROTOR HOUSING HAVING AN ANNULAR CONFIGURATION WITH AN INTERNAL SURFACE SHAPED AS A TROCHOID, SAID CASTING HAVING DIMENSIONALLY MACHINED SIDES AND A ROUGH AS-CAST TROCHOID SURFACE, SAID CASTING HAVING AT LEAST ONE PASSAGE OPENING INTO SAID SURFACE WHICH IS TEMPORARILY CLOSED BY AN INERT PLUG DURING SUBSEQUENT PROCESSING, B. WITH SAID CASTING MAINTAINED AT A TEMPERATURE OF AT LEAST 200*F, APPLYING A THIN SELF-FUSED COATING OF HEATED NICKELALUMINIDE PARTICLES ACROSS SAID ENTIRE TROCHOID SURFACE TO FORM A LAYER THEREON WITH A THICKNESS NO GREATER THAN 0.01 INCH, C. IMMEDIATELY APPLYING A UNIFORM COATING OF CARBON STEEL PARTICLES HAVING AT LEAST THE OUTER SURFACES THEREOF HEATED TO A TEMPERATURE OF AT LEAST 2,000*F FOR SELF-FUSING WHEN IMPELLED AGAINST SAID FIRST COATED CASTING SURFACE,
Claim 3
Dependent Claim
22 words
The method as in claim 1, in which the plain carbon steel particles have a carbon range of between 0.8-1.2% by weight.
Claim 4
Dependent Claim
21 words
The method as in claim 1, in which the nickel-aluminide coating has an average thickness in the range of 0.001-0.008 inches.
Claim 5
Dependent Claim
25 words
The method as in claim 1, in which the plain carbon steel particle coating is deposited in a uniform thickness of at least 0.06 inches.
Claim 6
Dependent Claim
16 words
The method as in claim 1, in which the first coating layer is comprised of NiAl.
Claim 7
Dependent Claim
33 words
The method as in claim 1, in which the first coating layer is comprised of a material selected from the group consisting of the following particle chemistries: NiAl, Ni-bronze, Ni-Chromium, Ni-BC, and molybdenum.
Claim 8
Dependent Claim
42 words
The method as in claim 1, in which the trochoid surface of said rotor housing casting is machined to a finish of about 64-256 r.m.s. prior to deposition of any coatings thereon, said machining being followed by a very light grit blasting.
Claim 9
Dependent Claim
31 words
The method as in claim 1, in which the carbon steel coating of step (c) is deposited in a thickness at least 5 times the maximum thickness of said Ni-Al coating.
Claim 10
Dependent Claim
21 words
The method as in claim 1, in which the chromium coating is machined to a surface finish of about 20-30 r.m.s.
Claim 11
Dependent Claim
24 words
The method as in claim 1, in which the Ni-Al coating of step (b) is comprised of about 80% nickel and about 20% aluminum.
References Cited (Backward Citations)
US3674544A
Cited
US3705818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-09 | 1978-12-09 | 1979-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-09 | 1982-12-09 | 1983-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-09 | 1986-12-09 | 1987-06-10 | $7700.00 | Window Closed / Lapsed |