US3261407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter rotor system
Assignee: Lockheed Martin Corp
•
Filing: 1964-08-05
•
Granted: 1966-07-19
•
Expires: 1984-08-05
Abstract
No abstract record available.
Inventors
- 👤 Irven H Culver
- 👤 Thomas F Hanson
- 👤 Lance G Look
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:22
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/46; B64C27/473; B64C27/48; B64C27/33; B64C27/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
159 words
A HELICOPTER ROTOR SYSTEM COMPRISING: A ROTOR MAST; A ROTOR HUB ON SAID MAST; A PLURALITY OF ROTOR BLADES SPACED APART FROM SAID MAST; MEANS FOR EFFECTING FORWARD SWEEP OF EACH OF THE BLADES; A FLEXURE MEMBER EXTENDING RADIALLY FROM THE HUB AND FORMING THE CHIEF STRUCTURAL COMPONENT OF EACH OF THE BLADES, SAID MEMBER CARRYING THE BLADE CENTRIFUGAL FORCE, BLADE FLAPPING AND IN-PLANE BENDING MOMENTS, AND BLADE SHEAR LOADS TO THE HUB AND SAID MEMBER BEING TORSIONALLY SOFT TO PROVIDE FOR BLADE PITCH CHANGE; SAID MEMBER FURTHER HAVING A VARIABLE, FLAPPING AND IN-PLANE ELASTIC STIFFNESSES; A TORQUE TUBE PIVOTALLY CONNECTED TO THE HUB AND ENVELOPING THE PORTION OF SAID FLEXURE MEMBER BETWEEN THE BLADE AND THE MAST; A COUPLING MEMBER ATTACHED TO THE BLADE AND TO THE TORQUE FOR FLEXIBLE JOINDER THEREOF; SWASHPLATE UNIVERSALLY MOUNTED ON SAID MAST; AND A PITCH CONTROL LINK PIVOTALLY CONNECTED TO EACH TORQUE AND TO SAID SWASHPLATE FOR CHANGING PITCH OF THE BLADES.
Claim 2
Dependent Claim
159 words
A HELICOPTER ROTOR SYSTEM COMPRISING: A ROTOR MAST; A ROTOR HUB ON SAID MAST; A PLURALITY OF ROTOR BLADES SPACED APART FROM SAID MAST; MEANS FOR EFFECTING FORWARD SWEEP OF EACH OF THE BLADES; A FLEXURE MEMBER EXTENDING RADIALLY FROM THE HUB AND FORMING THE CHIEF STRUCTURAL COMPONENT OF EACH OF THE BLADES, SAID MEMBER CARRYING THE BLADE CENTRIFUGAL FORCE, BLADE FLAPPING AND IN-PLANE BENDING MOMENTS, AND BLADE SHEAR LOADS TO THE HUB AND SAID MEMBER BEING TORSIONALLY SOFT TO PROVIDE FOR BLADE PITCH CHANGE; SAID MEMBER FURTHER HAVING A VARIABLE, FLAPPING AND IN-PLANE ELASTIC STIFFNESSES; A TORQUE TUBE PIVOTALLY CONNECTED TO THE HUB AND ENVELOPING THE PORTION OF SAID FLEXURE MEMBER BETWEEN THE BLADE AND THE MAST; A COUPLING MEMBER ATTACHED TO THE BLADE AND TO THE TORQUE FOR FLEXIBLE JOINDER THEREOF; SWASHPLATE UNIVERSALLY MOUNTED ON SAID MAST; AND A PITCH CONTROL LINK PIVOTALLY CONNECTED TO EACH TORQUE AND TO SAID SWASHPLATE FOR CHANGING PITCH OF THE BLADES.
References Cited (Backward Citations)
GB418698A
Cited
US2070657A
Cited
US2133043A
Cited
US2475337A
Cited
US2575533A
Cited
US2757745A
Cited
US3052305A
Cited
US2949967A
Cited
US3026942A
Cited
US3106964A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-07-18 | 1970-01-17 | 1970-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-07-18 | 1974-01-17 | 1974-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-07-18 | 1978-01-17 | 1978-07-19 | $7700.00 | Window Closed / Lapsed |