Patent US4137007A successfully refreshed from Google Patents.
US4137007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotor blade structure
Assignee: Individual
•
Filing: 1976-12-20
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Granted: 1979-01-30
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Expires: 1996-12-20
Abstract
Abstract A system of spars, each having a rectangular cross-section, is provided by placing the spars in lateral juxtaposition to one another like a plank to form a rotor blade. A skin of plastic foam is provided on the blade. The cross-sections of the spars, and the corresponding cross-sections of the blade, are varied in accordance with aerodynamic requirements. The spars are kept in position by means of clamps and/or connections and/or rings, forming an integral unit similar to a plank; and the integrated spars are directly attached to a hub or an electric generator.
Inventors
- 👤 Walter Schonball
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:08
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/46; B64C27/473; Y; Y02; Y02E; Y02E10/00; Y02E10/70; Y02E10/72
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
131 words
A rotor blade for a wind generator, comprising; a plurality of straight spars each having a longitudinally uniform, rectangular cross-section, and all secured to one another in lateral contact with one another to provide an integral unit thereof, similar to a plank; a skin of synthetic plastic foam embedding the unit of spars and defining a rotor blade having an exterior, aerodynamic profile, the number of the spars, transverse of the rotor blade, diminishing longitudinally from a hub end of the rotor blade, and the uniform cross-section of each spar having an area corresponding to the cross-sectional area of a directly embedding portion of the rotor blade; and means for attaching the hub end of the rotor blade to a hub, whereby the rotor blade has maximum strength near the hub.
Claim 2
Dependent Claim
131 words
A rotor blade for a wind generator, comprising; a plurality of straight spars each having a longitudinally uniform, rectangular cross-section, and all secured to one another in lateral contact with one another to provide an integral unit thereof, similar to a plank; a skin of synthetic plastic foam embedding the unit of spars and defining a rotor blade having an exterior, aerodynamic profile, the number of the spars, transverse of the rotor blade, diminishing longitudinally from a hub end of the rotor blade, and the uniform cross-section of each spar having an area corresponding to the cross-sectional area of a directly embedding portion of the rotor blade; and means for attaching the hub end of the rotor blade to a hub, whereby the rotor blade has maximum strength near the hub.
Claim 3
Dependent Claim
22 words
A rotor blade according to claim 1 in which the spars are glued to one another for their securing to one another.
Claim 4
Dependent Claim
26 words
A rotor blade according to claim 1 in which the spars are of aluminum and are welded to one another for their securing to one another.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-01-29 | 1982-07-31 | 1983-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-29 | 1986-07-31 | 1987-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-29 | 1990-07-31 | 1991-01-30 | $7700.00 | Window Closed / Lapsed |