US4417848A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Containment shell for a fan section of a gas turbine engine
Assignee: RTX Corp
•
Filing: 1982-02-01
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Granted: 1983-11-29
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Expires: 2002-02-01
Abstract
Abstract A fan case 30 which extends circumferentially about a fan rotor assembly 26 in a turbofan gas turbine engine 10 is disclosed. The fan case has a shell 66 outwardly of the rotor assembly for blocking the rotor blade 38 during a blade failure from penetrating the portion of the shell immediately outwardly of the rotor blade. The material of the shell increases in thickness in the axially rearward direction and has a maximum thickness rearward of a reference plane passing through the mid-chord point of the rotor blade.
Inventors
- 👤 Kurt M. Dembeck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:48
CPC Classifications
F; F01; F01D; F01D21/00; F01D21/04; F01D21/045; F05; F05D; F05D2220/00; F05D2220/30; F05D2220/32; F05D2220/327; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
112 words
In an axial flow gas turbine engine of the type having a fan case which includes a shell extending circumferentially about an array of fan rotor blades, and having an axis of symmetry As the improvement which comprises: a shell having a thickness of material in the radial direction which increases in the axially rearward direction and which has a maximum thickness rearward of a plane P 2 perpendicular to the axis of symmetry As and passing through the mid-chord point of one of the rotor blades wherein the increasing thickness of the shell selectively increases the cross-sectional area of the case to reinforce the case against the impact of blade fragments.
Claim 2
Dependent Claim
112 words
In an axial flow gas turbine engine of the type having a fan case which includes a shell extending circumferentially about an array of fan rotor blades, and having an axis of symmetry As the improvement which comprises: a shell having a thickness of material in the radial direction which increases in the axially rearward direction and which has a maximum thickness rearward of a plane P 2 perpendicular to the axis of symmetry As and passing through the mid-chord point of one of the rotor blades wherein the increasing thickness of the shell selectively increases the cross-sectional area of the case to reinforce the case against the impact of blade fragments.
Claim 3
Dependent Claim
64 words
The shell for a fan case of claim 1 wherein said rotor blade has a tip having a trailing edge, wherein a second plane P 3 extends through the trailing edge and extends perpendicular to the axis of symmetry As, and wherein a region bounded by the first plane P 2 and the second plane P 3 contains the maximum thickness of the shell.
Claim 4
Dependent Claim
95 words
The shell for a fan case of claim 1 wherein said rotor blade has a tip having a trailing edge wherein the trailing edge of said blade is spaced a distance L from the stacking line of the blade, wherein a second plane P 4 extends through a point rearwardly of the trailing edge a distance L and extends perpendicular to the axis of symmetry As to form a region extending between the first plane P 2 and the second plane P 4 , wherein the maximum thickness of the shell is in said region.
Claim 5
Dependent Claim
27 words
The shell for a fan case of claims 1, 2 or 3 wherein the thickness of material increases at a constant rate in the axially rearward direction.
Claim 6
Dependent Claim
21 words
The shell for a fan case of claim 1 wherein the thickness of material increases in at least one non-uniform increment.
Claim 7
Dependent Claim
20 words
The shell of a fan case of claim 5 wherein the thickness of material increases in a plurality of steps.
Claim 8
Dependent Claim
53 words
The invention as claimed in claims 1, 2 or 3 wherein each rotor blade has a tip having a leading edge and wherein the shell has a first thickness radially outwardly of the leading edge region and has a maximum thickness which is at least twenty percent (20%) greater than the first thickness.
Claim 9
Dependent Claim
36 words
The fan case of claims 1, 2 or 3 wherein the rotor blade has a tip having a leading edge region and wherein a flange radially outwardly of the leading edge region extends from the shell.
References Cited (Backward Citations)
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US2930521A
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GB1369229A
Cited
US3843278A
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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) | 1986-11-28 | 1987-05-30 | 1987-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-28 | 1991-05-30 | 1991-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-28 | 1995-05-30 | 1995-11-29 | $7700.00 | Window Closed / Lapsed |