Patent US3087690A successfully refreshed from Google Patents.
US3087690A
Expired / Lapsed
US
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Rotor with two joints in drive shaft
Assignee: Doman Helicopters Inc
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Filing: 1961-01-30
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Granted: 1963-04-30
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Expires: 1981-01-30
Abstract
No abstract record available.
Inventors
- 👤 Glidden S Doman
- 👤 Pont Stephen Du
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:34
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/37; B64C27/41; B64C27/22; B64C27/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
198 words
A ROTOR FOR A HELICOPTER HAVING A FUSELAGE AND THE LIKE COMPRISING A NON-ROTATING TUBULAR PYLON ADAPTED TO BE CARRIED BY THE FUSELAGE, A ROTOR UNIVERSAL JOINT CARRIED BY THE PYLON INCLUDING AN OUTER SHELL AND A JOINT CENTER AND A CENTRAL CAVITY, A ROTOR HEAD ROTATABLY MOUNTED ON THE ROTOR UNIVERSAL JOINT INCLUDING A ROTOR HUB AND MEANS CARRIED BY THE HUB TO MOUNT A PLURALITY OF BLADES FOR PITCH CHANGE UPON THEIR LONGITUDINAL AXIS, A DRIVE SHAFT PASSING THROUGH THE PYLON AND HAVING AN AXIS; AND A SHAFT UNIVERSAL JOINT UNIT OPERATIVELY CONNECTED AT ONE END WITH THE DRIVE SHAFT AND OPERATIVELY CONNECTED AT THE OTHER END WITH THE ROTOR HUB INCLUDING A PAIR OF CARDAN JOINTS, ONE JOINT BEING LOCATED INBOARD OF AND THE OTHER JOINT BEING LOCATED OUTBOARD OF THE CENTER OF THE ROTOR UNIVERSAL JOINT, THE CARDAN JOINTS BEING PHASED 90* APART, A CENTER LINK CONNECTING ONE CARDAN JOINT TO THE OTHER, THE MIDPOINT OF THE CENTER LINK BEING AT OR CLOSE TO THE CENTER OF THE ROTOR UNIVERSAL JOINT WHEN THE CARDAN JOINTS ARE IN AXIAL ALIGNMENT WITH THE DRIVE SHAFT, AND CONNECTING MEANS HAVING AXIAL FREEDOM OF MOVEMENT AND TORQUE RIGIDITY.
Claim 2
Dependent Claim
198 words
A ROTOR FOR A HELICOPTER HAVING A FUSELAGE AND THE LIKE COMPRISING A NON-ROTATING TUBULAR PYLON ADAPTED TO BE CARRIED BY THE FUSELAGE, A ROTOR UNIVERSAL JOINT CARRIED BY THE PYLON INCLUDING AN OUTER SHELL AND A JOINT CENTER AND A CENTRAL CAVITY, A ROTOR HEAD ROTATABLY MOUNTED ON THE ROTOR UNIVERSAL JOINT INCLUDING A ROTOR HUB AND MEANS CARRIED BY THE HUB TO MOUNT A PLURALITY OF BLADES FOR PITCH CHANGE UPON THEIR LONGITUDINAL AXIS, A DRIVE SHAFT PASSING THROUGH THE PYLON AND HAVING AN AXIS; AND A SHAFT UNIVERSAL JOINT UNIT OPERATIVELY CONNECTED AT ONE END WITH THE DRIVE SHAFT AND OPERATIVELY CONNECTED AT THE OTHER END WITH THE ROTOR HUB INCLUDING A PAIR OF CARDAN JOINTS, ONE JOINT BEING LOCATED INBOARD OF AND THE OTHER JOINT BEING LOCATED OUTBOARD OF THE CENTER OF THE ROTOR UNIVERSAL JOINT, THE CARDAN JOINTS BEING PHASED 90* APART, A CENTER LINK CONNECTING ONE CARDAN JOINT TO THE OTHER, THE MIDPOINT OF THE CENTER LINK BEING AT OR CLOSE TO THE CENTER OF THE ROTOR UNIVERSAL JOINT WHEN THE CARDAN JOINTS ARE IN AXIAL ALIGNMENT WITH THE DRIVE SHAFT, AND CONNECTING MEANS HAVING AXIAL FREEDOM OF MOVEMENT AND TORQUE RIGIDITY.
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) | 1966-04-29 | 1966-10-29 | 1967-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-04-29 | 1970-10-29 | 1971-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-04-29 | 1974-10-29 | 1975-04-30 | $7700.00 | Window Closed / Lapsed |