Lightweight structural columns

• US 4,259,821 A
• Filed: 06/29/1977
• Issued: 04/07/1981
• Est. Priority Date: 06/29/1977
• Status: Expired due to Term

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Bush, Harold G.
• Primary Examiner(s): Murtagh, John E.
• Application Number:
  US05/811,401
• Time in Patent Office: 1,378 Days
• Field of Search: 52/DIG. 10, 52/80, 52/81, 52/648, 52/148, 52/114, 52/649, 403/171, 403/176, 403/172, 428/902, 285/DIG. 12, 285/423, 285/319
• US Class Current: 52/309.1
• CPC Class Codes: B64G 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: E04B 1/1903 Connecting nodes specially adapted therefor
• CPC Class Codes: E04B 1/34326 mainly constituted by longitudinal elements
• CPC Class Codes: E04B 2001/1918 with connecting nodes having flat radial connecting surfaces
• CPC Class Codes: E04B 2001/1921 with connecting nodes having radial connecting stubs
• CPC Class Codes: E04B 2001/1927 of essentially circular cross section
• CPC Class Codes: E04B 2001/1963 Screw connections with axis at an angle, e.g. perpendicular, to the main axis of the strut
• CPC Class Codes: Y10S 428/902 High modulus filament or fiber
• CPC Class Codes: Y10S 52/10 Polyhedron
• CPC Class Codes: Y10T 403/342 Polyhedral
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

Lightweight half-lengths of columns for truss structures that are adapted for nestable storage and transport to facilitate fabrication of large area truss structures at a remote site and particularly adaptable for space applications.

Claims

1. A lightweight structural element adapted to be secured to a plurality of like members to form a truss structure comprising:

an elongated hollow body having a first end and tapering along the body length to a second end;

a first fitting secured to said first end and so constructed and arranged as to form engaging surfaces for attachment to an identical fitting secured to another identical structural element, and a second fitting secured to said second end and having an extension thereon to facilitate attachment of said second end to other elements;

said first fitting being provided with a first length slidably received within said first end of said hollow body, a second length thereof integral with said first length and forming an annular shoulder exteriorly along the circumference of said hollow body, and a third length thereof integral with said first and said second lengths and forming a plurality of equal width fingers disposed in equal spaced adjacency along the circumference of said second length and wherein the spacing between any two individual fingers is at least as wide as an individual finger, and

said elongated body being formed of a graphite/epoxy composite material.

2. The lightweight structural element of claim 1 wherein said plurality of equal width fingers are provided with tab protrusions at the ends thereof, said tab protrusions projecting perpendicularly inwardly toward the longitudinal center to provide a surface area for contacting an annular shoulder on a like structural element when two elements are forcibly connected by an axial force directed along the longitudinal axis thereof and the tips of said tab protrusions being provided with an inwardly tapered surface.

3. The lightweight structural element of claim 1 wherein the circumferential area of said second length disposed between said fingers is also provided with a tapered end surface and serving to engage the tapered surface tip of individual fingers on a like structural element to assist in springing the individual fingers over said second length for lock engagement with said annular shoulder thereon.

4. The lightweight structural element of claim 1 wherein said fingers have an inherent spring resiliency to permit attachment of said element to a like element by slidably positioning said fingers on a like element such that said fingers lock onto the annular shoulder on the like element.

5. A lightweight structural element adapted to be secured to a plurality of like members to form a truss structure comprising:

an elongated hollow body having a first end and tapering along the body length to a second end,

a first fitting secured to said first end and so constructed and arranged as to form engaging surfaces for attachment to an identical fitting secured to another identical structural element, and a second fitting secured to said second end and having an extension thereon to facilitate attachment of said second end to other elements,

said second fitting being provided with a first length slidably received within said second end;

a frustoconical portion integral with said first length and having an annular shoulder thereon adapted to abut against said second end; and

, said extension being bifurcated and integral with and tapering away from said frustoconical portion to an essentially pointed tip, and

said elongated hollow body being formed of a graphite/epoxy composite material.

6. The lightweight structural element of claim 5 wherein said bifurcated extension is provided with at least one diametrical opening therethrough and adapted to receive lock means for securing said element to a member receivable within the bifurcated extension.

7. A lightweight truss structure comprising in combination:

a plurality of elongated structural columns interconnected to form the truss structure,

each said column being formed of two hollow connected half-length segments and tapering from an enlarged center section to reduced diameter ends of essentially one-half the diameter of said center section,

each said half-length segment being provided with identical sliding fit lock connecting elements extending therefrom at an enlarged end thereof to facilitate column construction from any two half-length segments,

each said half-length segment being provided with second end fittings at the reduced diameter ends thereof to facilitate connection of these ends to other of said columns to thereby form a unitary lightweight truss structure.

8. The combination of claim 7 wherein each said second end fitting is provided with a bifurcated tip and rigid cluster bracket means having angular disposed exterior fingers thereon are securely positionable within said bifurcated tips to thereby connect a plurality of said columns for forming said truss structure.