US3139937A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary wing aircraft
Assignee: Boelkow Entwicklungen KG
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Filing: 1961-07-21
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Granted: 1964-07-07
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Expires: 1981-07-21
Abstract
No abstract record available.
Inventors
- 👤 Derschmidt Hans
- 👤 Eck Gerhard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:20
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/54; B64C27/32; B64C27/37; B64C27/41
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
237 words
A HELICOPTER COMPRISING A ROTARY CENTRAL ROTOR HEAD, A MAIN ROTOR SHAFT MOUNTED FOR ROTATION WITHIN SAID ROTOR HEAD, A PLURALITY OF ROTOR BLADES MOUNTED ON SAID HEAD FOR ROTATION THEREWITH, MEANS MOUNTING SAID BLADES TO SAID ROTOR HEAD FOR PIVOTAL LEAD AND LAG MOVEMENT IN ADDITION TO THEIR ROTATION WITH SAID ROTOR HEAD, A SWASH PLATE MOUNTED CONCENTRICALLY AROUND SAID ROTOR SHAFT FOR PIVOTAL MOVEMENT ABOUT AN AXIS SUBSTANTIALLY PERPENDICULAR TO SAID SHAFT FOR INCLUDING SAID SWASH PLATE FOR CONTROLLING PIVOTAL LEAD AND LAG MOVEMENT OF SAID BLADES, MEANS ROTATABLE AROUND SAID SWASH PLATE, MEANS FOR CONTROLLING THE INCLINATION OF SAID SWASH PLATE, A PLURALITY OF PIVOTAL CRANK ARM LEVER MEMBERS OF A NUMBER CORRESPONDING TO THE NUMBER OF SAID BLADES, MEANS PIVOTALLY MOUNTING SAID CRANK ARM LEVER MEMBERS ON SAID SHAFT FOR ROTATION THEREWITH AND FOR PIVOTAL ROCKING MOVEMENT ABOUT AN AXIS SUBSTANTIALLY PERPENDICULAR TO THE AXIS OF SAID SHAFT, RESPECTIVE ONES OF SAID CRANK LEVER MEMBERS HAVING A FIRST ARM, MEANS FOR CONNECTING SAID FIRST ARM TO AN ASSOCIATED ONE OF SAID BLADES FOR CAUSING PIVOTAL LEAD AND LAG MOVEMENT OF SAID BLADES, AND A SECOND ARM, MEANS FOR CONNECTING SAID SECOND ARM TO SAID MEANS ROTATABLE AROUND SAID SWASH PLATE PERMITTING MOVEMENT OF SAID CRANK LEVER MEMBERS RELATIVE TO EACH OTHER, SAID CRANK LEVER MEMBERS BEING ROCKABLE IN ACCORDANCE WITH THE INCLINATION OF SAID SWASH PLATE UPON ROTATION OF SAID MAIN ROTOR SHAFT.
Claim 2
Dependent Claim
237 words
A HELICOPTER COMPRISING A ROTARY CENTRAL ROTOR HEAD, A MAIN ROTOR SHAFT MOUNTED FOR ROTATION WITHIN SAID ROTOR HEAD, A PLURALITY OF ROTOR BLADES MOUNTED ON SAID HEAD FOR ROTATION THEREWITH, MEANS MOUNTING SAID BLADES TO SAID ROTOR HEAD FOR PIVOTAL LEAD AND LAG MOVEMENT IN ADDITION TO THEIR ROTATION WITH SAID ROTOR HEAD, A SWASH PLATE MOUNTED CONCENTRICALLY AROUND SAID ROTOR SHAFT FOR PIVOTAL MOVEMENT ABOUT AN AXIS SUBSTANTIALLY PERPENDICULAR TO SAID SHAFT FOR INCLUDING SAID SWASH PLATE FOR CONTROLLING PIVOTAL LEAD AND LAG MOVEMENT OF SAID BLADES, MEANS ROTATABLE AROUND SAID SWASH PLATE, MEANS FOR CONTROLLING THE INCLINATION OF SAID SWASH PLATE, A PLURALITY OF PIVOTAL CRANK ARM LEVER MEMBERS OF A NUMBER CORRESPONDING TO THE NUMBER OF SAID BLADES, MEANS PIVOTALLY MOUNTING SAID CRANK ARM LEVER MEMBERS ON SAID SHAFT FOR ROTATION THEREWITH AND FOR PIVOTAL ROCKING MOVEMENT ABOUT AN AXIS SUBSTANTIALLY PERPENDICULAR TO THE AXIS OF SAID SHAFT, RESPECTIVE ONES OF SAID CRANK LEVER MEMBERS HAVING A FIRST ARM, MEANS FOR CONNECTING SAID FIRST ARM TO AN ASSOCIATED ONE OF SAID BLADES FOR CAUSING PIVOTAL LEAD AND LAG MOVEMENT OF SAID BLADES, AND A SECOND ARM, MEANS FOR CONNECTING SAID SECOND ARM TO SAID MEANS ROTATABLE AROUND SAID SWASH PLATE PERMITTING MOVEMENT OF SAID CRANK LEVER MEMBERS RELATIVE TO EACH OTHER, SAID CRANK LEVER MEMBERS BEING ROCKABLE IN ACCORDANCE WITH THE INCLINATION OF SAID SWASH PLATE UPON ROTATION OF SAID MAIN ROTOR SHAFT.
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) | 1967-07-07 | 1968-01-06 | 1968-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-07-07 | 1972-01-06 | 1972-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-07-07 | 1976-01-06 | 1976-07-07 | $7700.00 | Window Closed / Lapsed |