US4552510A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radial type ceramic turbine rotor and method of producing the same
Assignee: NGK Insulators Ltd
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Filing: 1984-02-13
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Granted: 1985-11-12
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Expires: 2004-02-13
Abstract
Abstract A radial type ceramic turbine rotor comprises a shaft portion, a hub integrally connected to the shaft portion, a blade portion integrally formed on said hub, and an end surface on a gas exit side of the hub extending from an end surface of the blade portion in the proximity of the hub. According to the present invention, a fillet is formed at a circular connection between the blade portion and the hub, on the gas exit side of the rotor. The fillet has a concave surface with a radius of curvature of greater than 3 mm. The radial type ceramic turbine rotor of this invention is produced by the steps of injection molding a ceramic material in such a manner that the radius of curvature is more than 3 mm after sintering, removing a plasticizer included in the turbine rotor and sintering it under a normal pressure, thereby precluding the formation of cracks in the fillet.
Inventors
- 👤 Mizuno Takeyuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:38
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/638; C04B35/632; C04B35/634; F; F01; F01D; F01D5/00; F01D5/12; F01D5/28; F01D5/284; F01D5/34; F02; F02B; F02B1/00; F02B1/02; F02B1/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
92 words
A radial type ceramic turbine rotor comprising a shaft portion, a hub integrally connected to said shaft portion, a blade portion integrally formed on said hub, an end surface on a gas exit side of the hub extending from an end surface of said blade portion in the proximity of said hub, and a fillet formed at a circular connection between said blade portion and said end surface on the gas exit side of the hub, said fillet comprising a concave surface having a radius of curvature of greater than 3 mm.
Claim 2
Dependent Claim
92 words
A radial type ceramic turbine rotor comprising a shaft portion, a hub integrally connected to said shaft portion, a blade portion integrally formed on said hub, an end surface on a gas exit side of the hub extending from an end surface of said blade portion in the proximity of said hub, and a fillet formed at a circular connection between said blade portion and said end surface on the gas exit side of the hub, said fillet comprising a concave surface having a radius of curvature of greater than 3 mm.
Claim 3
Dependent Claim
23 words
The radial type ceramic turbine rotor as set forth in claim 1, wherein said radius of curvature is not greater than 10 mm.
Claim 4
Dependent Claim
20 words
The radial type ceramic turbine rotor as set forth in claim 1, wherein said radius of curvature is 4-6 mm.
Claim 5
Independent Claim
133 words
A method of producing a radial type ceramic turbine rotor which comprises a shaft portion, a hub integrally connected to said shaft portion, a blade portion integrally formed on said hub, an end surface on a gas exit side of the hub extending from an end surface of said blade portion in the proximity of said hub, said method comprising the steps of injection molding a ceramic material into an injection molding die, said injection molding die producing a fillet at a circular connection between said blade portion and said end surface on the gas exit side of the hub, said fillet comprising a concave surface having a radius of curvature of greater than 3 mm, after sintering, removing a plasticizer from the injection molded rotor and sintering the rotor under atmospheric pressure.
Claim 6
Independent Claim
133 words
A method of producing a radial type ceramic turbine rotor which comprises a shaft portion, a hub integrally connected to said shaft portion, a blade portion integrally formed on said hub, an end surface on a gas exit side of the hub extending from an end surface of said blade portion in the proximity of said hub, said method comprising the steps of injection molding a ceramic material into an injection molding die, said injection molding die producing a fillet at a circular connection between said blade portion and said end surface on the gas exit side of the hub, said fillet comprising a concave surface having a radius of curvature of greater than 3 mm, after sintering, removing a plasticizer from the injection molded rotor and sintering the rotor under atmospheric pressure.
Claim 7
Dependent Claim
40 words
The method as set forth in claim 4, wherein a ceramic material to be injection molded comprises at least one material selected from the group consisting of silicon nitride, silicon carbide, sialon and substances which produce these materials when sintered.
Claim 8
Dependent Claim
18 words
The method as set forth in claim 4, wherein the rotor is hydrostatically pressed prior to being sintered.
Claim 9
Dependent Claim
17 words
The method as set forth in claim 4, wherein the rotor is sintered in a nitrogen atmosphere.
Claim 10
Dependent Claim
23 words
The method as set forth in claim 4, wherein the rotor is heated to 500° C. for 10 hours to remove the plasticizer.
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) | 1988-11-11 | 1989-05-13 | 1989-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-11 | 1993-05-13 | 1993-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-11 | 1997-05-13 | 1997-11-12 | $7700.00 | Window Closed / Lapsed |