AU602807B2

AU602807B2 - A space frame

Info

Publication number: AU602807B2
Application number: AU28695/89A
Authority: AU
Inventors: Edwin Thomas Codd
Original assignee: Harley Systems Pty Ltd
Current assignee: Harley Systems Pty Ltd
Priority date: 1988-01-22
Filing date: 1989-01-23
Publication date: 1990-10-25
Anticipated expiration: 2009-01-23
Also published as: AU2869589A

Description

6~3- ~i"ta i COMMONWEALTH OF AUSTRALIA oo o 0 0 000 0 0 00 0 0 00 S0 0 0000 0 00 00 0 0 00 00 0o 0 0 @0 000 do a O 00 o 0 Patents Act 1952 Name of Applicant Address of Applicant Actual Inventor Address for Service HARLEY SYSTEMS PTY. LTD.

10 Shettleston Street, ROCKLEA. QLD. 4106

AUSTRALIA.

EDWIN THOMAS CODD GRANT ADAMS COMPANY, Patent Trade Mark Attorneys, 333 Adelaide Street, BRISBANE. QUEENSLAND. 4000

AUSTRALIA.

COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: 160,U "A SPACE FRAME" The following statement is a full description of the invention including the best method of performing it known to the applicant.

THIS INVENTION relates to a space frame.

The space f rame described and illustrated in the specification of Australian Patent No. 538693 is of double-layer flat grid type, in which both the upper and the lower grids are composed of similar size squares similarly oriented, but relatively displaced so that a node of the upper grid is located over the centre of a square of the lower grid, nodes of the two grids being interconnected by oblique web members or struts.

Although this configuration of space frame is widely adopted, in certain applications it is preferred o that a space frame of double-layer flat grid type should o have one grid skewed or angularly displaced by 450 relative to the other.

00 15 fae Certain other applications call for a space faeof "egg-crate" type in which the upper and lower grids are composed of similar size squares similarly oo~ooriented, and with the nodes of the upper grid directly o 0 above the corresponding nodes of the lower grid, oblique struts f rom each upper grid node being connected to o *nodes of the lower grid which are relatively displaced longitudinally and laterally, the struts therefore lying in the vertical planes of corresponding chords of the upper and lower grids.

The general object of the present invention is to provide a space f rame of either of such types which is particularly simple to make and assemble.

With the foregoing and other objects in view, the invention resides broadly in a space frame of ft 30 double-layer flat grid type wherein, at a node: two chords are superimposed; one pair of opposed oblique struts in a verti-*cal plane through one chord have terminals disposed on that chord; a second pair of opposed oblique struts 2

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lying in a vertical plane through the other chord have terminals interposed between the two chords; and the chords and strut terminals at the node being interconnected by connectors through the chords and the strut terminals.

Other features of the invention will become apparent from the following description.

In order that preferred embodiments of the invention may be readily understood and ca. 'ed into practical effect, reference is now made to the *accompanying drawings, wherein:

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0e FIG. 1 is a diagrammatic plan view of part of a a space frame of the type in which one grid is skewed °tOO .relative to the other; FIG. 2 is a partly broken-away perspective view of nodes of the space frame shown in FIG. 1; FIG. 3 is a partly broken-away perspective view of a strut of the space frame; FIG. 4 is a plan view of a node of the lower grid of a space frame according to the invention; FIG. 5 is a partly broken-away perspective view of a modified space frame strut; and FIG. 6 is a plan view of a space frame node according to an alternative embodiment of the invention.

4 2, In the space frame shown diagrammatically in SFIG. 1, the lower grid is composed of longitudinal chords 10 and lateral chords 11 arranged in squares.

The upper grid is composed of a series of chords 12 and a perpendicular series of chords 13 which are assembled in smaller squares and are, in plan view, at angles of I:45" to the chords of the lower grid, each lower grid node 14 (except for those at the corners or sides of the space frame) being directly below the centre of a square of the upper grid and therefore equidistant from four nodes 15 of the upper grid. The location of oblique 11 oow, uu ;,iw r struts 16 interconnecting the nodes of the upper and lower grids are indicated in broken lines in FIG. 1 and lie in vertical planes through the chords 10 and 11 of the lower grid.

The chords 10 and 11 of the lower grid, and the chords 12 and 13 of the upper grid, are all of fairly light gauge sheet metal roll-formed to lipped channels. At each node of the upper and the lower grid one chord member is superimposed on the other, the upper with its channel opening upwards, the lower one reversed.

The struts or web members 16 are of metal tube, their ends or terminals 17 and 17a being flattened and bent so that their planes are parallel and oblique to the axis of the main tubular part of the strut.

At each node 14 of the lower grid, the strut terminals 17, as shown in FIGS. 2, 3 and 4, are squarecut at their extremities, and they are each formed with two bolt holes 18. At each node 15 of the upper grid the strut terminals 17a are mitred at their extremities and each is formed with a single bolt hole 19.

At each upper grid node 15 two strut terminals 37a are interposed between the superimposed upper chord 12 and lower chord 13 and are secured by bolts through the chords and interposed strut terminal.

Preferably, as shown, four bolts 20 are used at the node, two securing the strut terminals as described, the others engaging spacer washers (not shown) of equal thickness to the strut terminals and interposed between the two chords.

At each lower grid node 14 the terminals 17 of one pair of opposed struts 16 are interposed between the lower or inverted chord channel 11ii and the upper chord channel 10, the other two opposed struts 17 having their terminals 17 seated within the upper chord channel Ai 1 -1- "ullrrrrrrrrrrar~*rrrrUU~r~.~lpzuu.~-L i Y- I 1 o ,O 0 00 0440 0.1 I 4 9040

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O O flush upon its web. In each pair of opposed struts 16, the square-cut extremities of the terminals abut. Four bolts 21 are passed through registering bolt holes 18 of the two pairs of strut terminals 17, and through registering bolt holes in the webs of the upper chord channel 10 and the lower chord channel 11.

If it should be necessary or desirable that a chord should be made up of two aligned sections, the arrangement of the parts allows the junction of sections 10 of either chord, or both, to be at the node. Such a junction in the upper chord 10 is indicated in FIG. 4 at 22 and it will be seen that the sections of the chord are held firmly together and in alignment by the four bolts 21.

15 The invention is applicable to the construction of a space frame of "egg-crate" type in which the upper and lower grids are similar, the nodes of the upper grid being directly above the nodes of the lower grid, the oblique struts interconnecting nodes of the two grids lying in vertical planes through the longitudinal and lateral chords of the two grids. In this embodiment of the invention the nodes of the lower grid are as described with reference to FIGS. 2 and 4, and the nodes of the upper grid are similar but inverted. The struts are modified as shown in FIG. the strut 16a having flattened and angled terminals 23 each of which is square-cut at its extremity and formed with twd' bolt holes 24.

In the modified node shown in FIG. 6 each of the struts 25 has a flattened and angled terminal 26 which is mitred at its extremity and formed with a single bolt hole. As before described, the terminals 26 of one pair of opposed struts 25 are interposed between the upper and lower chords 10 and 11, and the terminals of the other pair of opposed struts are seated within ii the channel of the upper chord 10. Four bolts 27 hold the assembly together, but the bolts in this instance are arranged at the corners of a square the sides of which are at angles of 450 to the chords. In a space frame of the type shown in FIG. i, the upper grid nodes will be similar to those shown in FIG. 2, and in a space frame of the "egg-crate" type, the upper grid nodes will be similar to those of the lower grid but inverted.

Space frames according to the invention will be found to be very effective in achieving the objects for which they have been devised. It will, of course, r be understood that the embodiments herein described and ,illustrated may be subject to many minor modifications of constructional detail and design, which will be readily apparent to persons skilled in the art, without departing from the scope of the invention hereinafter claimed.

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Claims

1. A space frame of double-layer flat grid type, the two grids being interconnected by oblique struts wherein, at a node: two chords are superimposed; one pair of opposed oblique struts in a vertical plane through one chord have terminals disposed on that chord; a second pair of c6pposed oblique struts lying in a vertical plane through the other chord have terminals interposed between the two chords; and the chorrls and strut terminals at the node being interconnected by connectors through the chords and the strut terminals.

2. A space frame according to Claim 1 wherein: the terminals of each pair of opposed struts are square-cut and in abutment.

3. A space frame according to either of the preceding claims wherein: the chords of the upper grid are skewed at angles of 450 relative to corresponding chords8 of the low%- grid; each said node is in thxe lower grid and equidistant from nodes of the upper grid; and at each node of the upper grid a pair of opposed oblique Gtruts have terminals interposed between two chords of the upper grid, the chords and strut terminals being interconnected by connectors through the chords and strut terminal!4.

4. A space. f rame according to any one of the preceding claims wherein: the chords of each grid are channels, the upper superimposed chord opening upwardly, the lower chord being inv~erted; and each of the oblique struts is tubular, its 1 terminals being flattened and bent to lie in planes oblique to the main unflattened tubular part.

A space frame substantially as herein described with reference to FIGS 1, 2, 3 and 4 of the accompanying drawings.

6. A space frame substantially as herein described with reference to FIGS. 4 and 5 of the accompanying drawings.

7. A space frame substantially as herein described with reference to FIG. 6 of the accompanying drawings. DATED this twenty-third day of January 1989. HARLEY SYSTEMS PTY. LTD., by its Patent Attor.eys, GRANT ADAMS COMPANY. A I