LIGHT WEIGHT CONTOURED LOAD CARRYING STRUCTURE

• US 3,779,487 A
• Filed: 04/19/1971
• Issued: 12/18/1973
• Est. Priority Date: 04/19/1971
• Status: Expired due to Term

• Current Assignee: Dale P. Abildskov, Larry J. Ashton
• Original Assignee: Dale P. Abildskov, Larry J. Ashton
• Inventors: Ashton, Larry J., Abildskov, Dale P.
• Primary Examiner(s): Reger, Duane A.
• Assistant Examiner(s): Barefoot, Galen L.
• Application Number:
  US05/134,973
• Time in Patent Office: 974 Days
• Field of Search: 244/123,117R,117A,129R,124,125,133 161/139,127,161 156/212-215 29/455R,455LM,460,471.1 416/187,226,230,241A
• US Class Current: 244/123.5
• CPC Class Codes: B64C 3/00 Wings ornithopter wings B64C33/02
• CPC Class Codes: Y10T 29/49879 Spaced wall tube or receptacle

Abstract

A lightweight load carrying foil structure including a plurality of elongated filament wound fiberglass tubular members disposed in side by side relationship and varying in cross section from one member to the other to have the opposite lateral sides thereof cooperate in defining the contour of a foil cross section that progressively increases in thickness from the leading edge of the foil cross section to form an intermediate portion defining a maximum thickness and to then progressively decrease in thickness to terminate in a relatively thin trailing edge. Fiberglass skin is stretched over the tubular members and cooperates therewith to form longitudinal cavities between such members. A filler foam fills the cavities and is held in place by the fiberglass skin to contain the members against bending when a moment is applied thereto.

Claims

1. A lightweight foil structure for mounting in a cantalever arrangement comprising:

a plurality of elongated load carrying filament wound fiberglass tubular members disposed in side by side relationship and varying in cross section from one to the other to have the opposite lateral sides thereof cooperate in defining the contour of the foil cross section that progressively increases in thickness from the leading edge of said foil cross section to form an intermediate portion defining a maximum thickness and to then progressively decrease in thickness to terminate in a relatively thin trailing edge;

fiberglass retaining means secured over said tubular members and cooperating therewith to form longitudinal cavities, said retaining means defining the external cross-section of said foil structure; and

lightweight filler means filling said cavities to closely fit the peripheries of said tubular members and having sufficient resistance to compression under normal operating conditions to provide for transfer of loads from said retaining means to said tubular means to cause said tubular means to cooperate with said retaining means in supporting said tubular members against buckling whereby lifting loads applied to the tip end of said structure as mounted cantaleverly which result in longitudinal bending moments will be resisted by said filament wound tubular members and buckling of said members will be resisted by said filler means in cooperation with said retaining means.

2. A lightweight structure as set forth in claim 1 wherein:

said tubular members are arcuate in cross section; and

said retaining means includes skin means stretched over said tubular members to cooperate with said tubular members to form said cavities.

3. A lightweight structure as set forth in claim 1 wherein:

said tubular members are circular in cross section and include a layer of circumferential filaments and a layer of spiral filaments.

4. A lightweight structure as set forth in claim 1 wherein:

said filler means is in the form of cellular foam.

5. A lightweight structure as set forth in claim 1 wherein:

said tubular members are circular in cross section.

6. A lightweight structure as set forth in claim 1 that includes:

elongated reinforcing members projecting down opposite sides of said tubular members to cooperate in supporting said members against bending.

7. A lightweight structure as set forth in claim 1 wherein:

said tubular members include elongated reinforcing members running down said one side thereof for supporting said tubular members against bending.

8. A lightweight structure as set forth in claim 1 wherein:

said tubular members are arcuate in cross section.

9. A lightweight structure as set forth in claim 1 wherein:

said tubular members are tapered from one end to the other.

10. A lightweight structure as set forth in claim 1 wherein:

said tubular members are formed with walls having a thickness less than one tenth of an inch.