US3814549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas turbine engine with power shaft damper
Assignee: Avco Corp
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Filing: 1972-11-14
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Granted: 1974-06-04
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Expires: 1992-11-14
Abstract
Abstract A gas turbine engine has an elongated thin wall, annular shaft extending from a rotor, including a turbine wheel to a reduction gear assembly for a variable pitch fan. A cylindrical metallic spring is placed in the interior of the shaft and is forced against its inner wall by centrifugal force to dampen vibrations.
Inventors
- 👤 V Cronstedt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:42
CPC Classifications
F; F02; F02K; F02K3/00; F02K3/02; F02K3/04; F02K3/06; F01; F01D; F01D25/00; F01D25/04; F02C; F02C7/00; F02C7/36; F16; F16F; F16F15/00; F16F15/10; F05; F05D; F05D2220/00; F05D2220/30; F05D2220/32; F05D2220/327; Y; Y10; Y10S; Y10S416/00; Y10S416/50
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
138 words
A gas turbine engine comprising: a generally annular housing; a rotor assembly including a turbine journaled in said housing for rotation at a relatively high rate; an output element journaled in said housing at a point spaced From said rotor assembly; an elongated, relatively thin wall annular shaft extending from said rotor assembly to said output element, said shaft being connected at its ends to said rotor assembly and said output element so that said shaft transmits substantially all of the torque between said rotor assembly and said output element; and a cylindrical helical spring of resilient metal received in the interior walls of said relatively thin wall shaft, said cylindrical spring being acted upon by centrifugal force to expand radially outward into frictional engagement with the interior walls of said shaft thereby dampening oscillations of said shaft.
Claim 2
Dependent Claim
138 words
A gas turbine engine comprising: a generally annular housing; a rotor assembly including a turbine journaled in said housing for rotation at a relatively high rate; an output element journaled in said housing at a point spaced From said rotor assembly; an elongated, relatively thin wall annular shaft extending from said rotor assembly to said output element, said shaft being connected at its ends to said rotor assembly and said output element so that said shaft transmits substantially all of the torque between said rotor assembly and said output element; and a cylindrical helical spring of resilient metal received in the interior walls of said relatively thin wall shaft, said cylindrical spring being acted upon by centrifugal force to expand radially outward into frictional engagement with the interior walls of said shaft thereby dampening oscillations of said shaft.
Claim 3
Dependent Claim
46 words
A gas turbine engine as in claim 1 wherein the diameter of the cylindrical spring in its relaxed state is larger than the diameter of the interior walls of said shaft whereby positive contact between the interior walls of the shaft and the spring is insured.
Claim 4
Dependent Claim
36 words
A gas turbine engine as in claim 1 wherein said shaft comprises an elongated central tube and end caps secured to the end of said tube, said spring being inserted before said end caps are secured.
Claim 5
Dependent Claim
27 words
A gas turbine engine as in claim 1 wherein said cylindrical spring is elongated and extends for a substantial portion over the interior walls of said shaft.
Claim 6
Dependent Claim
22 words
A gas turbine engine as in claim 1 wherein said output element is a bladed fan assembly driven by said output shaft.
Claim 7
Dependent Claim
47 words
A gas turbine engine as in claim 5 further comprising: a sun gear mounted on said shaft; at least one planet gear rotatable about a fixed axis and engaging said sun gear; and a ring gear engaging said planet gear and secured to said bladed fan assembly.
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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |