US4969326A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hoop shroud for the low pressure stage of a compressor
Assignee: General Electric Co
•
Filing: 1988-08-15
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Granted: 1990-11-13
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Expires: 2008-08-15
Abstract
Abstract An axial flow compressor for a bypass type jet engine has a low pressure stage which includes a one-piece, annular hoop shroud mounted to the airfoil of each of the rotor blades in the low pressure stage to divide the airflow entering the compressor into an outer, bypass airflow path and an inner airflow path directed to the higher pressure stages of the compressor. The hoop shroud is formed of circumferentially wound, parallel fibers such as silicone carbide fibers embedded in a metal matrix material such as titanium, wherein the volume ratio of the hoop shroud is approximately one-third fibers and two-thirds metal matrix material.
Inventors
- 👤 William D. Blessing
- 👤 Richard W. Stickles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:12
CPC Classifications
F; F01; F01D; F01D21/00; F01D21/04; F01D21/045; F01D5/00; F01D5/12; F01D5/22; F04; F04D; F04D29/00; F04D29/08; F04D29/083; F04D29/26; F04D29/32; F04D29/321; Y; Y02; Y02T; Y02T50/00; Y02T50/60; Y10; Y10S; Y10S60/00; Y10S60/909
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
113 words
Apparatus for dividing the airflow entering a low pressure stage of a jet engine compressor having low and high pressure stages, wherein a stage includes a rotor blade having a tip and root, said apparatus comprising: a one-piece, continuous annular hoop shroud bonded to said airfoil directly within a notch formed at a location intermediate the root and tip of the rotor blade; said annular hoop shroud forming an outer air flow path for a portion of the air entering the compressor to bypass the higher pressure stages of the compressor, and an inner airflow path for another portion of the air entering the compressor to flow into the higher pressure stages thereof.
Claim 2
Dependent Claim
113 words
Apparatus for dividing the airflow entering a low pressure stage of a jet engine compressor having low and high pressure stages, wherein a stage includes a rotor blade having a tip and root, said apparatus comprising: a one-piece, continuous annular hoop shroud bonded to said airfoil directly within a notch formed at a location intermediate the root and tip of the rotor blade; said annular hoop shroud forming an outer air flow path for a portion of the air entering the compressor to bypass the higher pressure stages of the compressor, and an inner airflow path for another portion of the air entering the compressor to flow into the higher pressure stages thereof.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 in which said annular hoop shroud is formed of a plurality of circumferentially wound, substantially parallel fibers embedded in a metal matrix material.
Claim 4
Dependent Claim
13 words
The apparatus of claim 2 in which said fibers are silicone carbide filaments.
Claim 5
Dependent Claim
14 words
The apparatus of claim 2 in which said metal matrix material is titanium metal.
Claim 6
Dependent Claim
36 words
The apparatus of claim 2 in which said fibers comprise about one-third of the volume of said annular hoop shroud and said metal matrix material comprises about two-thirds of the volume of said annular hoop shroud.
Claim 7
Dependent Claim
74 words
The apparatus of claim 1 in which the low pressure stage of the compressor includes a row of circumferentially spaced stator vanes axially spaced from said rotor blades, each of said stator vanes mounting a stator shroud, said annular hoop shroud being formed with a circumferentially extending sealing tip adapted to engage a surface of said stator shroud mounted to said stator vanes to seal said outer airflow path from said inner airflow path.
Claim 8
Dependent Claim
56 words
The apparatus of claim 1 in which said hoop shroud has a top surface and a bottom surface, said hoop shroud being bonded directly within said notch of said airfoil of said rotor blades by a weldment on both said top and bottom surfaces of said hoop shroud, said weldments being formed of aluminum brazing material.
Claim 9
Dependent Claim
131 words
A low pressure stage of a compressor in a jet engine, wherein the compressor includes a rotor and a compressor casing, said stage comprising: an annular row of circumferentially spaced, rotor blades extending radially outwardly from the rotor toward the casing of the compressor of the jet engine, each of said rotor blades having an airfoil formed with a notch on the aft, trailing edge thereof which is radially spaced from said rotor; a one-piece, continuous annular hoop shroud fixedly mounted directly within said notch in each of said rotor blades; an annular row of spaced stator vanes extending radially inwardly from the casing of the compressor toward said rotor, said stator vanes mounting a stator shroud in position to sealingly engage said annular hoop shroud mounted to said rotor blades.
Claim 10
Dependent Claim
131 words
A low pressure stage of a compressor in a jet engine, wherein the compressor includes a rotor and a compressor casing, said stage comprising: an annular row of circumferentially spaced, rotor blades extending radially outwardly from the rotor toward the casing of the compressor of the jet engine, each of said rotor blades having an airfoil formed with a notch on the aft, trailing edge thereof which is radially spaced from said rotor; a one-piece, continuous annular hoop shroud fixedly mounted directly within said notch in each of said rotor blades; an annular row of spaced stator vanes extending radially inwardly from the casing of the compressor toward said rotor, said stator vanes mounting a stator shroud in position to sealingly engage said annular hoop shroud mounted to said rotor blades.
Claim 11
Dependent Claim
28 words
The apparatus of claim 8 in which said annular hoop shroud is formed of a plurality of circumferentially wound, substantially parallel fibers embedded in a metal matrix material.
Claim 12
Dependent Claim
36 words
The apparatus of claim 9 in which said fibers comprise about one-third of the volume of said annular hoop shroud, and said metal matrix material comprises about two-thirds of the volume of said annular hoop shroud.
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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) | 1993-11-12 | 1994-05-14 | 1994-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-12 | 1998-05-14 | 1998-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-12 | 2002-05-14 | 2002-11-13 | $7700.00 | Window Closed / Lapsed |