US4006932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inflatable drag reducer for land vehicles
Assignee: United States Department of Transportation
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Filing: 1975-07-21
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Granted: 1977-02-08
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Expires: 1995-07-21
Abstract
Abstract A transport vehicle with a front end that leads the vehicle during normal movement thereof and a substantially planar surfaced rear end that trails the vehicle during such movement. Mounted on the rear end is an inflatable enclosure that when inflated possesses convergent contoured surfaces that extend from the edges of the rear end's planar surface. An inflation mechanism is operable by a driver of the vehicle to inflate the enclosure and thereby reduce the effects of base drag during relatively high speed movement of the vehicle. Also operable by the driver is a deflation mechanism that can be operated to deflate the enclosure into a stowed position when the vehicle is not in use or operating at low speeds in confined areas.
Inventors
- 👤 Alan T. McDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:39
CPC Classifications
B; B62; B62D; B62D35/00; B62D35/001; B62D35/004
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
104 words
A vehicle comprising: a front end that leads said vehicle during normal movement thereof; a rear end with a substantially planar surface that trails said vehicle during normal movement thereof; an inflatable enclosure secured to said rear end, said enclosure when inflated having convergent contoured surfaces extending from the edges of said planar surface and further comprises a substantially flat rear surface spaced from said planar surface and connected to said contoured surfaces; wherein said contoured surfaces comprise cusp portions that project rearwardly from the periphery of said flat rear surface; inflation means for inflating said enclosure; and deflation means for deflating said enclosure.
Claim 2
Dependent Claim
104 words
A vehicle comprising: a front end that leads said vehicle during normal movement thereof; a rear end with a substantially planar surface that trails said vehicle during normal movement thereof; an inflatable enclosure secured to said rear end, said enclosure when inflated having convergent contoured surfaces extending from the edges of said planar surface and further comprises a substantially flat rear surface spaced from said planar surface and connected to said contoured surfaces; wherein said contoured surfaces comprise cusp portions that project rearwardly from the periphery of said flat rear surface; inflation means for inflating said enclosure; and deflation means for deflating said enclosure.
Claim 3
Dependent Claim
32 words
A vehicle according to claim 1 wherein said flat rear surface is spaced between five and eight feet from said planar surface and has an area of between 50 and 70% thereof.
Claim 4
Dependent Claim
44 words
A vehicle according to claim 1, wherein said inflation means comprises air supply means responsive to the air pressure generated aerodynamically from vehicle motion including tube means extending between said enclosure and an air inlet orifice mounted on said front end and opening forwardly.
Claim 5
Dependent Claim
36 words
A vehicle according to claim 3 wherein said air supply means comprises valve means for controlling automatically said aerodynamically generated air flow through said tube means and disposed for operation by a driver of said vehicle.
Claim 6
Dependent Claim
18 words
A vehicle according to claim 4 wherein said deflation means comprises aspirator pump means for evacuating said enclosure.
Claim 7
Dependent Claim
52 words
A vehicle according to claim 1 wherein said inflated enclosure comprises a pair of inflatable enclosures each connected to one of a pair of doors that form said planar surface, each of said inflated enclosures comprises a substantially flat rear surface spaced from said planar surface and connected to said contoured surfaces.
Claim 8
Dependent Claim
24 words
A vehicle according to claim 6 wherein said contoured surfaces comprise cusp portions that project rearwardly from the periphery of said flat rear surface.
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) | 1980-02-08 | 1980-08-09 | 1981-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-08 | 1984-08-09 | 1985-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-08 | 1988-08-09 | 1989-02-08 | $7700.00 | Window Closed / Lapsed |