Patent US4850803A successfully refreshed from Google Patents.
US4850803A
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Ceramic radial turbine rotor
Assignee: NGK Insulators Ltd
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Filing: 1987-09-24
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Granted: 1989-07-25
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Expires: 2007-09-24
Abstract
Abstract A ceramic radial turbine rotor made of a ceramic material having a strength s (kg/mm2) includes blade tips having a thickness t (mm). A product st2 of strength s and t2 (square of t) is representative of resistance to breakage of the rotor to foreign objects colliding against blades of the rotor. The product st2 fulfills a relation st2>/=5x104 vm+33. In this case, v is a circumferential speed of tip ends of inducers of blades of the rotating rotor when the blades are damaged by steel balls having a mass m (kg) colliding against the blades in a steel ball collision test of blades of a ceramic radial turbine rotor, and vm is a product of v and m.
Inventors
- 👤 Keiji Kawasaki
- 👤 Kiminari Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:04
CPC Classifications
F; F01; F01D; F01D21/00; F01D21/003; F01D5/00; F01D5/02; F01D5/04; F01D5/043; F01D5/12; F01D5/28; F01D5/284; F05; F05D; F05D2200/00; F05D2200/20; F05D2200/22; F05D2200/221
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
127 words
A ceramic radial turbine rotor, comprising: a blade body having a plurality of blade tip portions which are highly resistant to breakage due to collisions with foreign objects, said blade body being made of a ceramic material having a strength s(kg/mm 2 ) and said blade tip portions having a thickness t (mm), wherein s and t are selected such that the following equation is fulfilled: s·t.sup.2 ≧(5=10.sup.4) V.sup.· m+33 wherein V(m/sec) is a circumferential speed of an outermost radial portion of said blade tip portions when said radial turbine rotor is rotating, and m (kg) is the mass of a steel ball which collides against said body during a steel ball collision test used to evaluate said radial turbine rotor rotating at said circumferential speed V(m/sec).
Claim 2
Dependent Claim
127 words
A ceramic radial turbine rotor, comprising: a blade body having a plurality of blade tip portions which are highly resistant to breakage due to collisions with foreign objects, said blade body being made of a ceramic material having a strength s(kg/mm 2 ) and said blade tip portions having a thickness t (mm), wherein s and t are selected such that the following equation is fulfilled: s·t.sup.2 ≧(5=10.sup.4) V.sup.· m+33 wherein V(m/sec) is a circumferential speed of an outermost radial portion of said blade tip portions when said radial turbine rotor is rotating, and m (kg) is the mass of a steel ball which collides against said body during a steel ball collision test used to evaluate said radial turbine rotor rotating at said circumferential speed V(m/sec).
Claim 3
Dependent Claim
26 words
A ceramic radial turbine rotor according to claim 1, wherein said ceramic material is selected from the group consisting of silicon nitride, silicon carbide and sialon.
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) | 1992-07-24 | 1993-01-23 | 1993-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-24 | 1997-01-23 | 1997-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-24 | 2001-01-23 | 2001-07-25 | $7700.00 | Window Closed / Lapsed |