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US3934922A Expired / Lapsed US ⏱️ 0.0 years remaining

Aerodynamic drag reduction devices for surface vehicles

Assignee: Aerovironment Inc
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Filing: 1974-09-05
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Granted: 1976-01-27
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Expires: 1994-09-05
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Abstract

Abstract Apparatus combined with or combinable with a vehicle body having a longitudinally elongated corner from which body surfaces extend at an angle, one of the surfaces presented forwardly toward oncoming air flow, and the other surface extending generally rearwardly away from that corner, the apparatus comprising A. means for preventing, reducing, or delaying separation of the flow boundary layer from said other surface rearwardly of said corner at normal operating speeds of the vehicle, B. said means comprising a longitudinally elongated protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of a first of said body surfaces said protrusion surface having a first longitudinally elongated terminal extent merging toward said first body surface in spaced relation to said corner, and second longitudinally elongated terminal extent merging toward a second of said body surfaces proximate said corner.

Inventors

  • 👤 Paul B MacCready, Jr.
  • 👤 Peter B. S. Lissaman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 16:10
CPC Classifications
B; B62; B62D; B62D35/00; B62D35/001

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 225 words
In combination, a. a vehicle body having an exterior front wall, an exterior side wall and an exterior top wall, said side wall meeting said front wall at a vertical corner, and said top wall meeting said front wall at a horizontal corner, b. means for preventing, reducing, or delaying separation of the flow boundary layer from said side and top walls rearwardly of said corners at normal operating speeds of the vehicle, c. said means comprising two cooperating elongated protrusions respectively extending parallel to said two corners, each protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of said front wall, said protrusion surface having first elongated extent merging toward said front wall at a shallow angle therefrom and in a generally transverse direction extending away from the corner paralleling that protrusion and terminally joined to and extending along said front wall in spaced relation to said corner such that the first elongated extent substantially merges with the front wall, and second elongated extent merging generally toward said corner and terminally joined to and extending along said body proximate said corner such that the second elongated extent substantially merges with a body wall proximate said corner whereby each corner is enveloped by one protrusion, d. said two protrusions extending generally perpendicular toward one another and mating proximate the intersection of said corners.
Claim 2
Dependent Claim 225 words
In combination, a. a vehicle body having an exterior front wall, an exterior side wall and an exterior top wall, said side wall meeting said front wall at a vertical corner, and said top wall meeting said front wall at a horizontal corner, b. means for preventing, reducing, or delaying separation of the flow boundary layer from said side and top walls rearwardly of said corners at normal operating speeds of the vehicle, c. said means comprising two cooperating elongated protrusions respectively extending parallel to said two corners, each protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of said front wall, said protrusion surface having first elongated extent merging toward said front wall at a shallow angle therefrom and in a generally transverse direction extending away from the corner paralleling that protrusion and terminally joined to and extending along said front wall in spaced relation to said corner such that the first elongated extent substantially merges with the front wall, and second elongated extent merging generally toward said corner and terminally joined to and extending along said body proximate said corner such that the second elongated extent substantially merges with a body wall proximate said corner whereby each corner is enveloped by one protrusion, d. said two protrusions extending generally perpendicular toward one another and mating proximate the intersection of said corners.
Claim 3
Dependent Claim 22 words
The combination of claim 1 wherein each protrusion extends outwardly of said front wall to maximum extent between 2 and 20 inches.
Claim 4
Dependent Claim 22 words
The combination of claim 1 wherein each protrusion surface has a generally hook-shaped cross-section in planes normal to the direction of elongation.
Claim 5
Dependent Claim 33 words
The combination of claim 1 including a generally wedge shaped element projecting outwardly from at least one protrusion, for inhibiting separation of the flow from the body wall rearwardly of said one protrusion.
Claim 6
Dependent Claim 16 words
The combination of claim 1 including a flow turning spaced outwardly of at least one protrusion.
Claim 7
Dependent Claim 18 words
The combination of claim 1 wherein the bulk of each said protrusion projects forwardly of said front wall.
Claim 8
Dependent Claim 20 words
The combination of claim 1 wherein each protrusion comprises a one-piece, thin-walled molded unit consisting of glass fibers and resin.
Claim 9
Dependent Claim 23 words
The combination of claim 1 including a protrusion extending lengthwise proximate a corner formed by the intersection of the top and side walls.
Claim 10
Dependent Claim 225 words
For combination with a vehicle body having an exterior front wall, an exterior side wall and an exterior top wall, said side wall meeting said front wall at a vertical corner, and said top wall meeting said front wall at a horizontal corner, a. means for preventing, reducing, or delaying separation of the flow boundary layer from said side and top walls rearwardly of said corners at normal operating speeds of the vehicle, b. said means comprising two cooperating elongated protrusions respectively extending parallel to said two corners, each protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of said front wall, said protrusion surface having first elongated extent merging toward said front wall at a shallow angle therefrom and in a generally transverse direction extending away from the corner paralleling that protrusion and terminally joined to and extending along said front wall in spaced relation to said corner such that the first elongated extent substantially merges with the front wall, and second elongated extent merging generally toward said corner and terminally joined to and extending along said body proximate said corner such that the second elongated extent substantially merges with a body wall proximate said corner whereby each corner is enveloped by one protrusion, c. said two protrusions extending generally perpendicularly toward one another and mating proximate the intersection of said corners.
Claim 11
Dependent Claim 225 words
For combination with a vehicle body having an exterior front wall, an exterior side wall and an exterior top wall, said side wall meeting said front wall at a vertical corner, and said top wall meeting said front wall at a horizontal corner, a. means for preventing, reducing, or delaying separation of the flow boundary layer from said side and top walls rearwardly of said corners at normal operating speeds of the vehicle, b. said means comprising two cooperating elongated protrusions respectively extending parallel to said two corners, each protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of said front wall, said protrusion surface having first elongated extent merging toward said front wall at a shallow angle therefrom and in a generally transverse direction extending away from the corner paralleling that protrusion and terminally joined to and extending along said front wall in spaced relation to said corner such that the first elongated extent substantially merges with the front wall, and second elongated extent merging generally toward said corner and terminally joined to and extending along said body proximate said corner such that the second elongated extent substantially merges with a body wall proximate said corner whereby each corner is enveloped by one protrusion, c. said two protrusions extending generally perpendicularly toward one another and mating proximate the intersection of said corners.
Claim 12
Dependent Claim 220 words
In combination a. a vehicle body having two elongated intersecting corners from each of which body surfaces extend at an angle, one of said surfaces presented forwardly toward oncoming relative air flow and other surfaces extending generally rearwardly away from said corners, said surfaces defining said corners, b. means for preventing, reducing, or delaying separation of the flow boundary layer from said other surfaces rearwardly of said corners at normal operating speeds of the vehicle, c. said means comprising two cooperating elongated protrusions respectively extending parallel to said two corners, each protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of a first of said body surfaces which extends toward each of said two corners, said protrusion surface having first elongated extent merging toward said first body surface in a generally transverse direction extending away from the corner paralleling that protrusion and terminally joined to said first body surface in spaced relation to said corner, and second elongated extent merging generally toward said corner and terminally joined to said body proximate said corner whereby each corner is enveloped by one protrusion, d. said two protrusions extending generally perpendicularly toward one another proximate the intersection of said corners, e. each protrusion including an inflatable section, and means to inflate said section to present said arcuate outer surface, as defined.
Claim 13
Dependent Claim 220 words
In combination a. a vehicle body having two elongated intersecting corners from each of which body surfaces extend at an angle, one of said surfaces presented forwardly toward oncoming relative air flow and other surfaces extending generally rearwardly away from said corners, said surfaces defining said corners, b. means for preventing, reducing, or delaying separation of the flow boundary layer from said other surfaces rearwardly of said corners at normal operating speeds of the vehicle, c. said means comprising two cooperating elongated protrusions respectively extending parallel to said two corners, each protrusion having a substantially smooth, arcuate outer surface projecting smoothly outwardly of a first of said body surfaces which extends toward each of said two corners, said protrusion surface having first elongated extent merging toward said first body surface in a generally transverse direction extending away from the corner paralleling that protrusion and terminally joined to said first body surface in spaced relation to said corner, and second elongated extent merging generally toward said corner and terminally joined to said body proximate said corner whereby each corner is enveloped by one protrusion, d. said two protrusions extending generally perpendicularly toward one another proximate the intersection of said corners, e. each protrusion including an inflatable section, and means to inflate said section to present said arcuate outer surface, as defined.
Claim 14
Dependent Claim 24 words
The combination of claim 10 wherein at least one protrusion includes a web section attached to said inflatable section and defining said elongated extent.
Claim 15
Dependent Claim 35 words
The combination of claim 10 wherein said means to inflate said section includes a duct having an open air inlet presented toward oncoming airflow, the duct communicable with a hollow defined by the inflatable section.
Claim 16
Dependent Claim 26 words
The combination of claim 10 wherein said means to inflate said section includes a gas pressure source communicable with a hollow defined by the inflatable section.
Claim 17
Dependent Claim 13 words
The combination of claim 1 wherein each protrusion comprises a thin-walled metallic unit.
Claim 18
Dependent Claim 311 words
In combination with a truck that includes a cab having a roof, and a box-like body rearwardly of the cab, the body having an exterior front wall facing forwardly toward the cab, said front wall extending downwardly substantially below the level of the cab roof, the body also having laterally opposite exterior side walls, and an exterior top wall, said side walls meeting said front wall at vertical corners, and said top wall meeting said front wall at a horizontal corner, the improvement that comprises, a. first and second protrusions respectively extending adjacent and along said vertical corners in enveloping relation therewith, each of said protrusions being linearly elongated in a vertical direction throughout its length from an upper location above the level of the cab roof to a lower location substantially below the cab roof level, each protrusion having two vertically elongated edge portions respectively attached in merging relationship to said body exterior front wall and to one body side wall, each protrusion having a vertically elongated mid-portion which is forwardly convex throughout the major vertical length of the protrusion, b. a third protrusion extending adjacent and along said horizontal corner in enveloping relation therewith, said third protrusion being linearly elongated in a horizontal and lateral direction throughout its length, said third protrusion having two horizontally elongated edge portions respectively attached in merging relationship to said body exterior front wall and to said body exterior top wall, said third protrusion having a horizontally elongated mid-portion which is forwardly convex throughout the major horizontal length of the protrusion, c. said third protrusion having opposite end portions respectively mating with upper end portions of said first and second protrusions, d. said protrusion convex mid-portions and edge portions configured to prevent, reduce or delay the separation of the air flow boundary layers from said exterior side and top walls rearwardly of said protrusions.
Claim 19
Dependent Claim 311 words
In combination with a truck that includes a cab having a roof, and a box-like body rearwardly of the cab, the body having an exterior front wall facing forwardly toward the cab, said front wall extending downwardly substantially below the level of the cab roof, the body also having laterally opposite exterior side walls, and an exterior top wall, said side walls meeting said front wall at vertical corners, and said top wall meeting said front wall at a horizontal corner, the improvement that comprises, a. first and second protrusions respectively extending adjacent and along said vertical corners in enveloping relation therewith, each of said protrusions being linearly elongated in a vertical direction throughout its length from an upper location above the level of the cab roof to a lower location substantially below the cab roof level, each protrusion having two vertically elongated edge portions respectively attached in merging relationship to said body exterior front wall and to one body side wall, each protrusion having a vertically elongated mid-portion which is forwardly convex throughout the major vertical length of the protrusion, b. a third protrusion extending adjacent and along said horizontal corner in enveloping relation therewith, said third protrusion being linearly elongated in a horizontal and lateral direction throughout its length, said third protrusion having two horizontally elongated edge portions respectively attached in merging relationship to said body exterior front wall and to said body exterior top wall, said third protrusion having a horizontally elongated mid-portion which is forwardly convex throughout the major horizontal length of the protrusion, c. said third protrusion having opposite end portions respectively mating with upper end portions of said first and second protrusions, d. said protrusion convex mid-portions and edge portions configured to prevent, reduce or delay the separation of the air flow boundary layers from said exterior side and top walls rearwardly of said protrusions.

References Cited (Backward Citations)

FR805960A Cited
US2037942A Cited
US2208075A Cited
US2737411A Cited
US2964352A Cited
US3425740A Cited
US3415566A Cited
US3834752A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-01-26 1979-07-28 1980-01-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-01-26 1983-07-28 1984-01-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-01-26 1987-07-28 1988-01-27 $7700.00 Window Closed / Lapsed

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