US3964838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Balanced airflow control valve for helicopter blade
Assignee: Individual
•
Filing: 1973-09-24
•
Granted: 1976-06-22
•
Expires: 1993-09-24
Abstract
Abstract An airflow control valve for a circulation control rotor helicopter blade wherein the airflow path is equally distributed about the closure element so as to prevent the generation of unbalanced pressure forces.
Inventors
- 👤 John D. Spargo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:32
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/325
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
66 words
A hollow airfoil; a fluid passage means longitudinally of the surface of said airfoil and communicating with its interior; said passage means including opposed interior openings along its length and a guide member, and fluid pressure balanced valve means; said valve means including an U-shaped member slidable axially of said passage means; means controlling operation of said U-shaped member for controlling flow through said passage means.
Claim 2
Dependent Claim
66 words
A hollow airfoil; a fluid passage means longitudinally of the surface of said airfoil and communicating with its interior; said passage means including opposed interior openings along its length and a guide member, and fluid pressure balanced valve means; said valve means including an U-shaped member slidable axially of said passage means; means controlling operation of said U-shaped member for controlling flow through said passage means.
Claim 3
Dependent Claim
25 words
An assembly as in claim 1 including means for reciprocating said generally U-shaped member into and out of sealing relationship with said fluid passage means.
Claim 4
Dependent Claim
18 words
An assembly as in claim 2 wherein said means for reciprocating said generally U-shaped member comprises a cam.
Claim 5
Dependent Claim
20 words
An assembly as in claim 3 including means to bias said generally U-shaped member against the action of said cam.
Claim 6
Dependent Claim
18 words
An assembly as in claim 3 including means at one end of said airfoil for actuating said cam.
Claim 7
Dependent Claim
25 words
An assembly as in claim 5 wherein said means for actuating said cam comprises a swash plate and follower assembly connected to rotate said cam.
References Cited (Backward Citations)
US2372030A
Cited
US2493041A
Cited
US2457936A
Cited
FR1270225A
Cited
US3139936A
Cited
US3524711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-22 | 1979-12-22 | 1980-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-22 | 1983-12-22 | 1984-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-22 | 1987-12-22 | 1988-06-22 | $7700.00 | Window Closed / Lapsed |