US3874819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Francis type runner for pump turbine
Assignee: Hitachi Ltd
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Filing: 1973-05-09
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Granted: 1975-04-01
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Expires: 1993-05-09
Abstract
Abstract A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, and a runner cone secured to said runner. Said runner cone has a curved lower end portion curved inwardly at a break point and is shaped so that L lies within the range of from 0.35D2 to 2.5D2 where L is the distance between the line passing through the center of the height of the outer end of said blades and a point in the vicinity of the break point in the curved lower end portion of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring. In the runner unit, the ratio D3/D2 is selected to lie within the range of 0<D3/D2<0.12 where D3 is the outer diameter of the curved lower end portion of said runner cone at the break point, so as to reduce vibrations and noises occurring in the runner.
Inventors
- 👤 Ryoichi Tamura
- 👤 Masayasu Okada
- 👤 Mituo Takase
- 👤 Masahiro Yamabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:21
CPC Classifications
F; F03; F03B; F03B3/00; F03B3/12; Y; Y02; Y02E; Y02E10/00; Y02E10/20
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
175 words
A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, a draft tube disposed at an outlet of the runner, and a runner cone secured to said runner, said runner cone having a substantially planar remote end and being shaped so that L lies within the range of from 0.35D2 to 2.5D2, said planar remote end protruding beyond a line passing through the lowermost ends of the blades toward the draft tube, where L is the distance between the line passing through the center of the height of the outer end of said blades and the remote end of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring, wherein the ratio D3/d2 is selected to lie within the range of 0< D3/D2< 0.12 where D3 is the outer diameter of the remote end of said runner cone.
Claim 2
Dependent Claim
175 words
A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, a draft tube disposed at an outlet of the runner, and a runner cone secured to said runner, said runner cone having a substantially planar remote end and being shaped so that L lies within the range of from 0.35D2 to 2.5D2, said planar remote end protruding beyond a line passing through the lowermost ends of the blades toward the draft tube, where L is the distance between the line passing through the center of the height of the outer end of said blades and the remote end of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring, wherein the ratio D3/d2 is selected to lie within the range of 0< D3/D2< 0.12 where D3 is the outer diameter of the remote end of said runner cone.
Claim 3
Dependent Claim
35 words
A Francis type runner unit as claimed in claim 1, wherein said runner cone is of non-perforated construction and is composed of a plurality of planar members defining a hollow space within said runner cone.
Claim 4
Dependent Claim
43 words
A Francis type runner unit as claimed in claim 2, wherein said planar members are disposed so as to substantially form an arc and are fixed to each other while making successively smaller angles withe respect to the main shaft of the turbine.
Claim 5
Dependent Claim
201 words
A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, a draft tube disposed at an outlet of the runner, and a runner cone secured to said runner, said runner cone having a curved lower end portion curved inwardly at a break point and being shaped so that L lies within the range of 0.35D2 to 2.5D2, the curved lower end of said runner cone protruding beyond the line passing through the lowermost ends of the blades toward the draft tube, where L is the distance between the line passing through the center of the height of the outer end of said blades and a point in the vicinity of the break point in the curved lower end portion of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring, wherein the ratio D3/D2 is selected To lie within the range of 0<D3/D2< 0.12 where D3 is the outer diameter of the curved lower end portion of said runner cone at the break point.
Claim 6
Dependent Claim
201 words
A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, a draft tube disposed at an outlet of the runner, and a runner cone secured to said runner, said runner cone having a curved lower end portion curved inwardly at a break point and being shaped so that L lies within the range of 0.35D2 to 2.5D2, the curved lower end of said runner cone protruding beyond the line passing through the lowermost ends of the blades toward the draft tube, where L is the distance between the line passing through the center of the height of the outer end of said blades and a point in the vicinity of the break point in the curved lower end portion of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring, wherein the ratio D3/D2 is selected To lie within the range of 0<D3/D2< 0.12 where D3 is the outer diameter of the curved lower end portion of said runner cone at the break point.
Claim 7
Dependent Claim
43 words
A Francis type runner unit as claimed in claim 4, wherein said runner cone is of non-perforated costruction and is composed of an upper planar member, an intermediate planar member and a lower planar member defining a hollow space within said runner cone.
Claim 8
Dependent Claim
47 words
A Francis type runner unit as claimed in claim 5, wherein said upper, intermediate and lower planar members are disposed so as to substantially form an arc and are fixed to each other while making successively smaller angles with respect to the main shaft of the turbine.
Claim 9
Dependent Claim
23 words
A Francis type runner unit as claimed in claim 4, wherein the lower end portion of said runner cone substantially planar in shape.
Claim 10
Dependent Claim
169 words
A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, and a runner cone secured to said runner, said runner cone having a curved lower end portion curved inwardly at a break point and being shaped so that L lies within the range of from 0.35D2 to 2.5D2 where L is the distance between the line passing through the center of the height of the outer end of said blades and a point in the vicinity of the break point in the curved lower end portion of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring, wherein the ratio D3/D2 is selected to lie within the range of 0< D3/D2< 0.12 where D3 is the outer diameter of the curved lower end portion of said runner cone at the break point.
Claim 11
Dependent Claim
169 words
A Francis type runner unit for a pump-turbine comprising a runner secured to a main shaft of the turbine and including a plurality of blades, a crown ring disposed above said blades and a shroud ring disposed beneath said blades, and a runner cone secured to said runner, said runner cone having a curved lower end portion curved inwardly at a break point and being shaped so that L lies within the range of from 0.35D2 to 2.5D2 where L is the distance between the line passing through the center of the height of the outer end of said blades and a point in the vicinity of the break point in the curved lower end portion of said runner cone, and D2 is the inner diameter of the outlet end of said shroud ring, wherein the ratio D3/D2 is selected to lie within the range of 0< D3/D2< 0.12 where D3 is the outer diameter of the curved lower end portion of said runner cone at the break point.
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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) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |