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US4421320A
Expired / Lapsed
US
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Boomerang
Assignee: Individual
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Filing: 1982-04-13
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Granted: 1983-12-20
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Expires: 2002-04-13
Abstract
Abstract The disclosure is directed to a multi-arm boomerang with a structural configuration with permits simple modification of operational flight characteristics. The boomerang comprises a plurality of airfoil-shaped arms spaced about a central axis with an airfoil-shaped control device, preferably in the form of a ring, interconnecting the arms. By altering the cross sectional shape of the control device means, the flight characteristics of the boomerang may be modified. Furthermore, by constructing the disclosed boomerang of a resilient material there is created an entertainment device with safety features far in advance of those heretofore known.
Inventors
- 👤 David P. Robson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:05
CPC Classifications
A; A63; A63B; A63B65/00; A63B65/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
82 words
In a boomerang with a plurality of airfoil-shaped arms spaced about a central axis and extending outwardly thereabout the improvement wherein: the boomerang has a top surface and an opposing bottom surface and an airfoil-shaped lift producing control means interconnecting said plurality of arms, said control means being generally open-centered and symmetrical about said central axis, said airfoil-shaped arms providing a net lift toward said top surface, said control means providing a net lift toward said bottom surface for controlling lay down.
Claim 2
Dependent Claim
82 words
In a boomerang with a plurality of airfoil-shaped arms spaced about a central axis and extending outwardly thereabout the improvement wherein: the boomerang has a top surface and an opposing bottom surface and an airfoil-shaped lift producing control means interconnecting said plurality of arms, said control means being generally open-centered and symmetrical about said central axis, said airfoil-shaped arms providing a net lift toward said top surface, said control means providing a net lift toward said bottom surface for controlling lay down.
Claim 3
Dependent Claim
18 words
The boomerang of claim 1 wherein: said control means and said arms are statically balanced about said axis.
Claim 4
Dependent Claim
12 words
The boomerang of claim 2 wherein: said control means comprises a ring.
Claim 5
Dependent Claim
14 words
The boomerang of claim 3 wherein: said arms are spaced symmetrically about said axis.
Claim 6
Dependent Claim
22 words
The boomerang of claim 4 wherein: said arms do not extend inwardly toward said axis beyond the inner periphery of sai ring.
Claim 7
Dependent Claim
18 words
The boomerang of claim 5 wherein: said arms and ring are generally planar and comprise a resilient material.
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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) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |