GB2192965A

GB2192965A - Space frame system

Info

Publication number: GB2192965A
Application number: GB08627671A
Authority: GB
Inventors: Tan Ee Ping
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-07-22
Filing date: 1986-11-19
Publication date: 1988-01-27
Anticipated expiration: 2006-11-19
Also published as: GB8627671D0; GB2192965B; GB8617910D0

Abstract

A frame system comprises a series of elongate frame members 12 connected to a series of nodes 14. The nodes 14 comprise spherical shells with at least eight uniformly spaced holes therein. Diagonal members are bolted to the shell itself, and horizontal/vertical members are connected to the arms of a cruciform cross bar located within the node which provides extra strength and transmits tension and/or compression stresses. <IMAGE>

Description

SPECIFICATION Frame system This invention relates to a frame system and in particular relates to a structural building frame system capable of providing large uninterrupted spans without columns.

According to the present invention there is provided a frame system which comprises a series of elongate frame members adapted to be connected to a series of nodes, the nodes comprising spherical shells with at least eight uniformly spaced holes therein, and a series of cruciform cross bars each adapted to be fixed within a node and to be connected to adjacent elongate frame members.

The elongate members are preferably tubular members and conveniently have threaded portions formed on or in or attached to each end. In one preferred construction the elongate members are hollow tubes having internally threaded truncated cone shaped portions welded to each end thereof.

The elongate members are fixed at each end to an adjacent node, for example with suitable bolt means passing through one of the holes in the node to engage the member. Preferably four holes in each node are spaced about the equator thereof at 900 intervals, and the remaining four holes are spaced uniformly about one hemisphere at 45" to the horizontal plane through the equator. The hemisphere opposite that bearing four of the holes may conveniently have a removable end cap or cover plate portion, to allow access to the interior thereof.

The cross bar has four arms, each of which aligns with one of the four equatorial holes in the node. Each arm of the cross bar is externally threaded and receives an internally threaded sleeve, which sleeve receives an externally threaded bar previously screwed into the conical part of an elongate frame member.

An external turning nut is provided on the threaded bar to provide, together with the sleeve on the cross bar, the required strong connection between the cruciform cross bar and the elongate frame member, to facilitate the direct transmission of tension or compression stress, and to give fixity and rigidity to the spherical shells, by tightening the said external turning nut and the sleeve against the contact surfaces of the spherical shell. The latter is achieved by manufacturing the radii of curvatures of the contact surfaces of the nut and sleeve to correspond to the external and internal radii of curvatures respectively of the spherical shell.

In this way, tension and/or compression stresses from the horizontal elongate frame members in both horizontal directions are transmitted directly through to its opposite member, through the cruciform cross bar, without inducing stresses in the spherical shell. Advantageously, the preferred stiffness and rigidity is imparted to the spherical shell, enabling it to withstand high stress distribution from the other four diagonal elongate frame members, the assembly of which will be described more fully hereinafter.

The cross bar has at its junction of the four arms a plain section which would be provided with an internally threaded hole or bracket to facilitate either a connection support for light fittings to be installed at the immediate base of the node, or for the above mentioned cover plate portion, or other items.

The sleeve, together with the threaded bar connected to the conical part of the elongate frame member and the washers which are provided between the external turning nut and the end of the conical part of the elongate frame member provides flexibility, and greater distances, tolerances and fabrication adjustments, without affecting the structural strength and aesthetic features.

In addition to the horizontal elongate frame members which are connected to the cruciform cross bar, four diagonal elongate frame members are connected to the spherical shell by means of a threaded bolt which is passed through each one of the remaining (ie nonequatorial) holes in the shell. The bolt is screwed by means of an external turning nut, into the conical portion of the elongate frame member and a washer is provided between the nut and the elongate frame member. This arrangement allows the required torque to be applied externally, and also advantageously caters for flexibility and greater distances, tolerances and fabrication adjustments.

The elongate frame member connected to any node can be installed or dismantled, even after the positions of adjacent nodes have been fixed.

The nodes forming part of the present invention are fabricated spherical shells which .are stream-lined, neat and aesthetically impressive, especially when stainless steel is used.

The size of the spherical shell may be minimised, provided the four diagonal bolts connecting the diagonal frame members to the shell can be conveniently installed from the inside of the shell before the cruciform cross bar is introduced.

The present invention provides a frame system incorporating small size, lightweight spherical shells strengthened by the cruciform bar connections which are highly practical, aesthetically pleasing and economical. Together with the flexibility for greater distance, tolerance, and fabrication adjustment, and convenient assembly the present invention proves most satisfactory as compared with previous modular construction methods.

The frame system of the invention may be manufactured from any suitable material but it is especially preferred that all the components be manufactured from stainless steel for strength, durability and attractive appearance.

The surface of the steel may be treated so as to alter the appearance thereof either by surface marxing, polishing or colouring.

The invention will be described further, by way of example, with reference to the accompanying drawings in which: Fig 1(a) to (d) illustrates elevation plan side elevation and perspective views respectively of an assembled framework in accordance with the invention; Fig 2 is an isometric view of the elongate members at a connection node; Fig 3 is a cross-sectional view of a connection node; Fig 4 is an exploded view of a connection node; Fig 5 is a-cross-sectional view of installed diagonal elongate members; Fig 6 is an exploded view of a diagonal elongate member connecting with a node; Fig 7 is an elevational view of an elongate member; Fig 8 is a cross-sectional view of an end part of an elongate member; Fig 9 is an end view of anelongate member corresponding to Fig 7 on an enlarged scale; Fig 10 is a top view of a connecting node;; Fig 11 is an exploded view of a connecting node; Fig 12 illustrates a suitable nut and bolt for use with the invention; Fig 13 illustrates a threaded bar; Fig 14 is a top view of a cruciform cross bar; Fig 15 is a side elevation corresponding to Fig 14; and Fig 16 is a cross-sectional view corresponding to Fig 15.

Referring to the drawings, a frame system in accordance with the invention generally designated 10 comprises pipe members 12 and nodes 14. The pipe members (as illustrated in Figs 7 to 9) comprise elongate tubular portions 16 having truncated conical end parts welded thereto, the conical parts 18 having internally threaded portions 20.

The nodes 14 comprise spherical shells 22 having eight hole 24 26 formed therein. Four of the holes 24 are spaced at- 900 intervals about the equator 28 of the node. The remaining four holes 26 are spaced between the holes 24 at an angle of 45" to the horizontal plane including the equator 28. The opposite hemisphere of the node 14 to that containing the holes 26 has a removable end cap or cover plate 30 allowing access to the interior of the spherical shell. A cover plate 30 is held in position by means of a screw or bolt 31 as described more fully hereinafter.

A cruciform locking bar 32 is provided to fit within each of the nodes 14. Each arm corresponds with one of the equatorial holes 24 of the node and is externally threaded at 36 to receive the internally threaded sleeve 40.

A threaded bar 38, initially screwed into the conical end section 18 of the elongate pipe member 16, can then be turned into and be accepted by the threaded sleeve 40, through the equatorial hole 24, after the nut 42 and washer 8 has been installed onto the threaded bar 38. The contact surfaces of nut 42 and sleeve 40 are machine-finished or manufactured so that their radii of curvatures correspond to the external and internal radii of curvatures of the spherical shell 22 respectively.

The threaded sleeve 38 is internally turned to be in contact with the inner surface of the spherical shell 22, followed by the final external tightening of the turning nut 42 onto the spherical shell 22. The spare washer 8 is then engaged into its final position.

The frame system according to the invention can conveniently be fabricated at the actual location and position of erection or prefabrication on the ground and lifted and connected positions. First of all a truss is formed by bolting diagonal elongate members in place through the holes 26 in a respective node using the bolts 46 and nuts 48. The bolts 46 engage the internally threaded portions 20 of the members 12 and the nuts 48 act in effect as lock nuts. Next the vertical and horzontal cords are connected through the holes 24 in the nodes 14 into the cruciform locking bar 32 by turning the threaded bars 38 into the internally threaded sleeve 40, followed by the tightening of the sleeve 40 and eventual tightening of the external turning nut 42.

The final adjustment and tightening can be carried out by tightening the hexagonal nut of each elongate member in contact with the external surface of its respective node 14. Upon final adjustment, alignment and installation of all the members in a particular system, the cover plates 30 of the nodes may be installed by screwing the bolt 31 through the end plates into a threaded hole 50 provided on the cruciform bars 32.

Where the frame system of the invention is used as framing for curtain walling or roof trusses, space plates or brackets and/or bolts may be provided on the elongate members and a top hole may be provided in each of the nodes respectively to facilitate easy connection of the curtain walling or roofing panels to the framing members.

The spherical shell configuration of the nodes 14 in the system of the invention takes advantage of the efficiency of shell characteristics since it is a continuous medium and a high proportion of the material from which it is made is used to capacity. It provides the most efficient cross-sectional shape and its material is conveniently distributed along the perimeter. The radius of gyration is constant for all axes passing through the centroid of cross-section. The cruciform locking bars 32 further strengthen the spherical nodes 14.

The system of the invention thus offers a light, strong and durable framing system which is resistant to the elements and aesthetically pleasing in appearance.

Claims

1. A frame system which comprises a series of elongate frame members adapted to be connected to a series of nodes, the nodes comprising spherical shells with at least eight uniformly spaced holes therein, and a series of cruciform cross bars each adapted to be fixed within a respective node and to be connected to adjacent elongate frame members.

2. A system as claimed in Claim 1 in which four holes in each node are spaced about the equator thereof at 90C intervals, and the remaining four holes are spaced uniformly about one hemisphere at 45C to the horizontal plane through the equator.

3. A system as claimed in Claim 1 or Claim 2 in which the hemisphere opposite that bearing four of the holes has a removable cap or cover plate portion to allow access to the interior thereof.

4. A system as claimed in any of the preceding Claims in which each cruciform cross bar has four arms, each of which aligns with one of the four holes spaced about the equator of the node.

5. A system as claimed in any of the preceding Claims in which the elongate members are tubular members.

6. A system as claimed in Claim 5 in which the tubular members have threaded portions formed on, or in, or attached to each end.

7. A system as claimed in Claim 6 in which the elongate members are hollow tubes having internally threaded truncated cone-shaped portions welded to each end thereof.

8. A system asclaimed in any of the preceding Claims in which the elongate members are fixed ateach end to an adjacent node.

9. A system as claimed in any of Claims 6 to 8 in which an elongate member is connected horizontally or vertically to an adjacent node by means of a threaded bar which passes through one of the four holes spaced about the equator of the node and which engages at one end thereof with the threaded portion of the elongate member and at the other end with an internally threaded sleeve surrounding one of the arms of the cross bar.

10. A system as claimed in any one of Claims 6 to 9 in which an elongate member is connected diagonally to an adjacent node by means of a threaded bolt which passes through one of the holes spaced about one hemisphere of the node and engages with the threaded portion of the elongate member.

11. A system as claimed in any of the preceding Claims manufactured from stainless steel.

12. A frame system according to Claim 1 and substantially as herein described.

13. A frame system substantially as herein described with reference to the accompanying drawings.