US3749518A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite blade root configuration
Assignee: RTX Corp
•
Filing: 1972-03-15
•
Granted: 1973-07-31
•
Expires: 1992-03-15
Abstract
Abstract In a fiber reinforced composite blade, the fibers are extended from the airfoil into the right and left side of the root. It is carefully determined which fibers are extended into the left side and which are extended into the right side to assure that all the fibers are wholly contained within the root and the minimum acceptable bend radius of the fibers is not violated.
Inventors
- 👤 A Alver
- 👤 W Pilpel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:33
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/14; F01D5/147; F01D5/28; F01D5/282; F05; F05D; F05D2240/00; F05D2240/80; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
159 words
A composite blade comprising an airfoil and a dovetail shaped root, the root hAving a centerplane dividing the root into left and right sides, said root also having a neck, said left side including a left tang and said right side including a right tang, the airfoil including a base, a leading and trailing edge, an unlimited region, and fibers oriented in a substantially spanwise direction, and at the base thereof the airfoil having both its leading and trailing edges on the left side of the root centerplane, fibers near the leading and trailing edges being limited fibers and said right tang being a safe area for said limited fibers, said limited fibers extending into the root, through the neck, and thereupon into said right tang, and fibers between said leading and trailing edge limited fibers being within said unlimited region and extending into the root, through the neck, and thereupon being divided between said left and right tangs.
Claim 2
Dependent Claim
159 words
A composite blade comprising an airfoil and a dovetail shaped root, the root hAving a centerplane dividing the root into left and right sides, said root also having a neck, said left side including a left tang and said right side including a right tang, the airfoil including a base, a leading and trailing edge, an unlimited region, and fibers oriented in a substantially spanwise direction, and at the base thereof the airfoil having both its leading and trailing edges on the left side of the root centerplane, fibers near the leading and trailing edges being limited fibers and said right tang being a safe area for said limited fibers, said limited fibers extending into the root, through the neck, and thereupon into said right tang, and fibers between said leading and trailing edge limited fibers being within said unlimited region and extending into the root, through the neck, and thereupon being divided between said left and right tangs.
Claim 3
Dependent Claim
174 words
A composite blade comprising an airfoil and a root, said airfoil including a pressure surface, a suction surface, and fibers oriented in a substantially spanwise direction and extending into aid root, said root having a centerplane dividing said root into left and right sides, said root also having a neck, sai airfoil having a plurality of regions of fibers, said regions including at least one limited region and one unlimited region, each of said regions including both fibers adjacent said pressure surface and fibers adjacent said suction surface, one side and one side only of said root including a safe area for each of said limited regions of fibers, all fibers within each of said limited regions passing into said root through said neck and extending into said safe area for said limited region of fibers, and fibers within said unlimited regions extending into said root through said neck and being divided between said left and right sides of said root without passing outside said root and without violating the fiber minimum bend radius.
Claim 4
Dependent Claim
174 words
A composite blade comprising an airfoil and a root, said airfoil including a pressure surface, a suction surface, and fibers oriented in a substantially spanwise direction and extending into aid root, said root having a centerplane dividing said root into left and right sides, said root also having a neck, sai airfoil having a plurality of regions of fibers, said regions including at least one limited region and one unlimited region, each of said regions including both fibers adjacent said pressure surface and fibers adjacent said suction surface, one side and one side only of said root including a safe area for each of said limited regions of fibers, all fibers within each of said limited regions passing into said root through said neck and extending into said safe area for said limited region of fibers, and fibers within said unlimited regions extending into said root through said neck and being divided between said left and right sides of said root without passing outside said root and without violating the fiber minimum bend radius.
Claim 5
Dependent Claim
59 words
The composite blade according to claim 2 wherein said airfoil includes a base, and each limited region is positioned entirely on one side of said centerplane at said base, and said safe area for each limited region is on the other side of said centerplane from said limited region and each unlimited region straddles said centerplane at said base.
Claim 6
Dependent Claim
62 words
The composite blade according to claim 3 wherein said root is dovetail shaped and said right side includes a right tang, said left side includes a left tang, and said safe area is a tang, said root including a wedge separating the fibers of said unlimited region within said left side from the fibers of said unlimited region within said right side.
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) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |