Field of the invention

[001] This invention relates to a connector system for use in panel construction systems, to connectors for use in such a connector system, to a construction system using such a connector system and to a method of construction for use in panel construction systems.

Background to the invention

[002] The invention finds application in the attachment of glass fibre reinforced concrete (GRC) panels to an underlying support structure, such as a steel framed structure and it will be described with reference to such an application by way of example. It will be appreciated that this is not intended to limit the invention to such applications.

[003] Unlike conventional panel construction, structural insulated panels being an example, GRC panels can be produced with surfaces that curve out of the plane. A good example is to be found in the fibreC™ GRC panels produced and sold by Rieder Smart Elements GmbH, Maishofen, Austria, which are conventionally planar, but which can be cast as curved panels. Being relatively thin (8 to 13 mm thick), the curvature of a fibreC™ panel will result in the front and back (top and bottom) surfaces of the panel being equivalently curved and it will be appreciated that the securement of such a curved panel to a non- curved support structure presents a problem.

[004] It is an object of the invention to address this problem.

Summary of the invention

[005] A connector system for structural elements constituted by a panel support structure and the panels supported thereby, the connector system comprising: a plurality of ball and socket connectors, each made up of initially discrete ball and socket assemblies; the ball assembly including means for connection to the one structural element and the socket assembly including means for connection to the other structural element; the ball and socket assemblies including means to adjust the distance between the structural element connection means on the ball and socket assemblies; and the ball and socket assemblies being adapted for connection to one another with some rotational freedom, the ball being adapted to be received rotationally within the socket. [006] In this specification, the ball and socket assemblies will be described with reference to examples in which the ball assemblies are secured to the structural elements constituted by the panel support structure, the socket assemblies being secured to the structural elements constituted by the panels. It will be appreciated that this is done purely for exemplary purposes, since an opposite arrangement (or a combination arrangement) could also be used, in which all or some of the ball assemblies are secured to the panels and all or some of the socket assemblies are secured to the support structure.

[007] The connector system may be used with structural elements in which the panel may be retained on a plane that is angled relatively to the plane of the panel support structure and in which the linear distances between points on the panel and corresponding points on the support structure may vary in direct proportion to the deviation of the panel plane from the plane of the support structure, the means to adjust the distance between the structural element connection points across individual ball and socket connectors being adapted to permit the different connectors in the connector system to accommodate the different linear distances between the panel and the support structure.

[008] In the preferred form of the invention, the connector system is adapted for use with structural elements constituted by panels and a panel support structure in which one or both sets of structural elements are curved on a plane of curvature and in which the plane of curvature of the panel may be different to that of the support.

[009] In such a structure the linear distances between points on the panel and corresponding points on the support structure may vary in direct proportion to the deviation, at that point, of the panel plane from the plane of the support structure (or in direct proportion to the deviation out of the plane of the curved panel, the support structure or both). To accommodate such deviation, the means to adjust the distance between the structural element connection points across individual ball and socket connectors may be adapted to permit the different connectors in the connector system to accommodate the different linear distances between the curved panel and the underlying panel support structure.

[0010] In addition, the difference in the plane angles (of the panel and support structure respectively) at different points on the curved panel differ with the curvature of the panel, the ball and socket assemblies being adapted for connection to one another with a predetermined degree of rotational freedom, thereby to accommodate the different plane angles of the structural elements relatively to one another, the rotational ability of the ball and socket connectors being adapted to permit the different connectors in the connector system to accommodate such differing plane angles at each point of connection.

[0011] A number of means are available to permit the adjustment of the distance between the structural element connection means across the ball and socket assembly, the preferred means being the provision of a two-part screw- threaded ball assembly, one part of which may be screwed into or out of the other to decrease or increase, respectively, the length of the ball assembly, thereby to adjust the distance between the connection means.

[0012] The invention includes a connector for use in a panel construction system, the connector including a ball and socket connector with initially discrete ball and socket assemblies, the ball assembly including means for connection to a structural element constituted by a panel support structure or a panel supported thereby and the socket assembly including means for connection to the other structural element, the ball and socket assemblies including means to adjust the distance between the structural _^ element connection means on the ball and socket assemblies and the ball and socket assemblies being adapted for connection to one another with a predetermined degree of rotational freedom, the ball being adapted to be received rotationally within the socket.

[0013] The invention includes a construction system using such the connector system and the connectors of the invention.

[0014] The invention includes a method of connecting at least two sets of structural elements, the first set being constituted by a panel support structure and the second set being constituted by the panels supported thereby, the method including the steps of: securing a plurality of ball and socket connectors, each made up of initially discrete ball and socket assemblies, to the structural elements, the ball assembly being connected to the one set of structural elements and the socket assembly being connected to the other set of structural elements; adjusting the distance between the structural element connection means on the ball and socket assemblies; and connecting the ball and socket assemblies to one another with a predetermined degree of rotational freedom, the ball of each ball and socket assembly being housed rotationally within the socket of its corresponding ball and socket assembly.

[0015] In the preferred form of the invention, the distance between the structural element connection means on the ball and socket assemblies is adjusted, before the ball and socket assemblies are secured to one another, by adjusting the distance of the ball from the the ball assembly connection means. Brief Description of the drawings

[0016] The invention will be further described with reference to the accompanying drawings in which:

Figure 1 is a diagrammatic isometric view of the connector system of the invention showing the structural elements to be connected, constituted by a panel support structure and a panel supported thereby;

Figure 2 is a sectional side elevation of a ball and socket assembly forming part of the connector system of Figure 1 ;

Figure 3 is a diagrammatic side view, partly in section, of part of a ball and socket assembly in place on a different support structure;

Figure 4 is a diagrammatic, exploded, isometric view of the ball and socket assembly in place on a support structure;

Description of embodiments of the invention

[0017] The drawings illustrate the connector system 10 of the invention used in an application in which curved, glass fibre reinforced concrete (GRC) panels 12 (such as the fibreC™ GRC panels of Rieder Smart Elements GmbH, Austria), are secured to an underlying support structure 14, such as a steel framed structure.

[0018] The connector system 10 consists of a plurality of ball and socket connectors 16, each made up of a ball assembly 18 and a socket assembly 20. The ball and socket assemblies 18, 20 are initially discrete and are intended to be connected to the panels 12 and the support structure 14. The ball and socket assemblies 18, 20 are connected to one another to connect the panels 12 to the support structure 14.

[0019] The ball assembly 18 is supported by a slider foot constituted by a slider base 24 with an internally threaded pedestal 26 arising therefrom. The slider base 24 is adapted for sliding engagement within a slideway forming part of the support structure 14. The attachment of the slideway to the support structure 14 and the attachment of the support base to the slideway will be described in greater detail below.

[0020] The ball 28 of the ball assembly 18 is adjustably mounted on the pedestal 26 by means of an externally screw-threaded post 30. Together the post 30 and pedestal 26 make up a ball support stalk 32 that is length- adjustable, in that the post 30 can be screwed into and out of the pedestal 26 to adjust the length of the stalk 32 and hence, the height (or distance) of the ball 28 from the slider base 24.

[0021] The socket assembly 20 consists of an open cup 34 within which the ball 28 can be rotatably received.

[0022] In the drawings, the cup 34 is shown as inverted because, in the structure assumed by the drawings, the panel 12 is supported operationally above the support structure 14. The panel 12 could however be suspended from the support structure, in which case the connector system will depend from the support structure and the cups 34 will open upwardly. By the same token, the ball assembly 18 is shown as being connected to the support structure 14 and the socket assembly 20 is connected to the panel 12, once again resulting in the cups 34 being inverted. It will be appreciated that the connector system may be connected the other way round, with the ball assembly connected to the panel and the socket assembly connected to the support structure, so that the sups 34 open upwardly.

[0023] The cup base has an attachment foot 36 that is formed with a plurality of attachment openings 38, each adapted to receive a screw, bolt, anchor or other fastener by means of which the cup 34 may be attached to the panel 12. In so-called invisible- or rear-fastening panel assembly systems, the fasteners may be undercut anchors 39, such as the undercut anchors supplied by KEIL Befestigungstechnik GmbH, Engelskirchen, Germany).

[0024] The mouth 40 of the cup 34 has a flared rim 42 to facilitate the engagement of the cups 34 with the balls 28 during assembly of the connector system 0.

[0025] In use, the cups 34, after engagement with the balls 28, will be secured in place by means of retaining pins 44 pressed into pin guide apertures 46 formed on either side of the cup 34. The pin guides 46 are located, within the cup 34, at points where a ball 28 (located in the cup 34 in use) narrows from its widest girth (the ball equator) to the point of attachment to the post 30, so that pins 44 inserted into the pin guides 46 in use, will trap the ball 28 within the cup without interfering with the rotation of the ball 28 relatively to the cup 34.

[0026] The cup 34 and pins 44 are preferably made from materials that will permit suspended attachment of the panels 2 to the supporting structure 14, the cups 34 and pins 44 being adapted to support the weight of the panels 12 when the panels 12 are installed upside down or in any other, essentially weight-bearing orientation.

[0027] To facilitate two-dimensional adjustment of the ball and socket assemblies 16 on and in the plane of the support structure 14, the system preferably includes a secondary support structure constituted by a plurality of extruded aluminium sections 48, each formed, on its upper surface, with a track or slideway 50.

[0028] The secondary support structure is adapted for securement on the primary support structure 14 by means of bolting through slotted apertures formed in the aluminium sections that allow small sideways adjustment of the secondary support structures on the support structure 4, in the one axis of the plane of the support structure 14. For adjustment in the other axis of the plane of the support structure 14, the slideway 50 is shaped complementally to the slider base 24 of the ball assembly 18 to permit sliding engagement of the slider base 24 within the slideway 50.

[0029] The screw adjustment of the ball and stalk assembly 18 provides the connector system 10 of this invention with the ability to accommodate three- dimensionally curved panels 12.

[0030] The ball and stalk assemblies 18 are first set on the secondary support structure and the ball heights (the linear distances of the balls 28 from the slider bases 24) are then adjusted to accommodate the plane or curved surfaces of the undersides of the panels 12 to be secured to the support structure 14.

[0031] The cups 34 are pre-assembled by the attachment of the cups 34 to the undersides of the panels 12 by means of appropriate anchors or fasteners.

[0032] The panels 12 are then lowered onto the balls 28, whereafter a fastener tool (not shown) is inserted into the gaps between adjacent panels 12 to insert the retaining pins 44 into the retaining pin guides, to secure the cups 34 to the balls 28 and hence the panels 12 to the support structure. [0033] With curved panels 12, the curvature of the panels 12 is accommodated by the fact that the cups 34 can engage the balls 28 at an angle. The permitted curvature of the panels 12 will be determined by the permitted engagement angle of the balls 28 with the cups 34 which angle, in turn, is determined by the ingress angle permitted by the flare angle of the flared rims 42 of the cups 34.

[0034] An alternative support structure, constituted by a cylindrical beam 1 4, is shown in Figure 3. To adapt the connector system of the invention to such an alternative structure, it is simply necessary to produce an alternative secondary support structure 148, in which no more than the base of the alternative secondary support structure 148 needs to change. Using a similar slideway 150 it is possible to retain the remaining components of the connector system.

[0035] It is difficult to support a freely curved surface structure on a conventional, non-curved support structure, unless one uses initially plastic materials, such as concrete or plastics. Most support structures are basically polyhedral, being made up of one or more polyhedrons (geometric solids with flat faces and straight edges). In such a structural system, the attachment surface of the supporting structure 14 and the attachment surface of the final curved surface 12 (cladding for instance) are spaced apart, but inconsistently so, the spacing distance varying inconsistently with varying convergence and divergence between the two surfaces across the entire structure and even across individual structural elements (cladding panels, for instance). In addition, the plane angles at each attachment point in such a structure will vary inconsistently with varying convergence and divergence between the two surfaces across the entire structure across individual structural elements.

[0036] This invention provides a structural translation mechanism between a curved final surface, such as a curved panel-clad exterior surface, and a non- curved or less curved supporting structure 14.

[0037] The connector system of this invention includes a structural translation mechanism by means of which the varying spacing and plane angles between the curved final surface and the less-curved support structure is accommodated, the ball and socket connectors 16 having the means to adjust to fit the varying spacing distances and the cups 34 permitting the balls 28 to enter the cups from a range of entry angles and permitting the balls 28 and cups 34 to rotate relatively to one another with the degree of rotational freedom required to adjust to the varying plane angles at each attachment point.

[0038] In this specification, the ball and socket connectors 16 and the panel 12 and support structures 14 have been described with reference to substantially horizontal reference planes. As indicated above however, the use of the retaining pins 44 makes it possible for the connector system 0 to retain its structural integrity in any gravitational orientation. In this way, the connector system 10 of the invention can be used for the translation of a planar support structure in any orientation, to a curved surface in substantially the same orientation, whether horizontal, vertical, upward- or downward facing, since the the ball and socket connectors 16 will bear load in any direction so that the surfaces of the structure can flow from floors, to walls, to ceilings to roofs.