PLASTIC FRAMES

Abstract: A set of frame component comprising a plurality of tubes (6) incorporating an internal longitudinal spline member (7) and a plurality of connecting members (9) incorporating two identical spigots (2, 3) ends formed with four longitudinally extending grooves (4) which are spaced about the periphery of each spigot (2, 3) at 90<o> intervals. The spigots (2, 3) of each connecting member are inserted in the ends of the tubes (6) with the splines (7) engaging a groove (4) in the spigots (2, 3) to locate the connecting member at a predetermined desired orientation.

Description: TITLE: PLASTIC FRAMES This invention relates to supporting frames and components for such frames and more particularly to supporting frames and components for furniture, although not restricted thereto. In recent years, furniture having supporting frames constructed from plastic plumbing pipe and connecting joint or fittings have become increasingly popular, especially as outdoor furniture and increasingly as indoor furniture. In many cases, the furniture is sold as a kit of parts for subsequent assembly by the purchaser. In assembling the furniture frame it is necessary to apply adhesive to the secured lengths of pipe and connecting joints as the frame components are assembled-. It is of course important that each joint be accurately positioned on the pipe before the adhesive sets to ensure that the opposite end of the pipe is at the correct position to accept the remaining frame components. In a majority of cases, the connecting joint should be accurately located at 90 to the attached pipe although in some cases other angles may be required, for example, where the connecting joints supports a bracing strut. It will be appreciated that an unskilled person may easily assemble the connecting joint on the pipe at a slightly displaced angle and once the adhesive sets, it is extremely difficult or impossible to rectify that error. As a result, a partial or complete set of frame components may well be wasted by a quite small error in the fitting of the various connecting joints. Another disadvantage of supporting frames constructed from plastic plumbing fittings is that the pipe is .inserted into the socket in the connecting joint and therefore leaves -unsightly discontinuities or steps inthe frame at each joint. Although the above discussion is directed to frames for furniture, the invention is equally applicable to other frames, such as display frames for shops, shelving and the like. It is the principal objec or tne present invention to provide frame components by means of which the problem of incorrect alignment is avoided and the problem of unsightly discontinuities is also preferably avoided. The invention provides a set of frame components comprising a plurality of generally elongate, hollow members of generally symmetrical cross-section and a plurality of connecting members each having at least two spigots extending therefrom and dimensioned to be received in said hollow members, each said spigot having at least one longitudinal groove or spline in its outer surface disposed at a predetermined angular relationship to the remainder of the connecting member, and said hollow members each having a longitudinal spline or groove formed internally thereof and dimensioned to co-operate with the or each groove or spline in said spigots. Preferably, the spigots are. formed with four grooves or splines arranged at 90 to each other about the periphery of the spigot and aligned with a predetermined directional axis of the connecting member. The outer configuration of the elongate hollow members is preferably the same as the outer configuration of the connecting members at a position adjacent the spigots. In this way, the outer surfaces of the connecting members an attached hollow members are substantially continuous whereby the unsightly discontinuities of the prior art are avoided. If desired, additional grooves may be arranged at 45 , 22% or at any other desired angle to suit the specific requirements of the frame to be constructed from the hollow members and connecting members. The elongate hollow members are most preferably tubular. While a tube formed with only one locating spline is believed to be adequate, two or more splines arranged in alignment with the respective grooves in the spigots of the connecting members may be provided. The tubes and connecting members are most suitably moulded from pvc or some other suitable plastic material and are fixed together by means or a suitable adhesive. However, in certain circumstances, the tubes, or for that matter the connecting members, may be made from other materials such as cast and extruded aluminium, wood or the like in which case any suitable method of connection may be used. The connecting members may be formed in any desired configuration to provide for the desired connections between adjacent tubes of the frame. In the case of frames for furniture, the spigots on the connecting members are predominantly arranged at 90 to each other. Examples of various preferred connecting members are described in greater detail below. It will be appreciated from the above that the provisio of connecting spigots having grooves with which splines in the elongate frame components may co-operate means that the various components may be assembled by an unskilled person without substantial risk of the frame components being incorrectly positioned relative to each.other. As mentioned above, the most common error in assembly is the displacement of a frame component slightly off the 90 position required and this eventually is completely avoided by means of the present invention. The present invention also provides a kit of parts for constructing a frame comprising the generally elongate hollow members and connecting members defined in greater detail above together with a set of suitable instructions as to their assembly. Preferred embodiments of the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a first connecting member embodying the invention; Figure 2 is an end view of the connector showing the grooves in the spigot; Figure 2A is a perspective view of one end of a frame tube embodying the invention; Figures 3 to 9 are perspective view of further connecting members embodying the invention; Figure 10 is a perspective view of a table incorporatin a frame embodying the invention; and Figure 11 shows the assembly instructions for assembling the table of Figure 10 from a kit of components embodying the invention. Referring firstly to Figures 1 and 2 of the drawings, the connecting member embodying the invention will be seen to comprise a generally tubular member having a central body portion 1 from which two identical spigots 2,3 extend. Each spigot is formed with four longitudinally extending grooves 4 which are spaced about the periphery of each spigot 2,3 at 90° intervals. Each spigot 2,3 is slightly chamfered at 5 to enable easy interconnection between the connecting member 1 and the other frame components which are in the form of tubes 6 as shown in Figure 2A of the drawings. It will be noted from Figure 2A that the frame tube 6 is formed with an internal spline 7 which extends longitudinally of the frmae tube 6 throughout its length. The frame tube 6 is preferably extruded from pvc which is preferably UV stabilised. Similarly the connecting member 1 is injection moulded from a similar grade of UV stabilised pvc. The advantages of the grooved spigots and co-operating splined tube is more apparent from the connecting members shown in Figures 3 to 9 of the accompanying drawings in which the spigots 2,3 extend at various angles from the central portion 1 of the connecting member. In the case of the embodiment of Figure 3, the connecting member is a right angle connector. Figure 4 shows a T-connector in which an additional aim and associated spigot 8 are added to the right angle connector of Figure 3. In the case of Figure 5, an additional leg and associated spigot 9 extends in the opposite direction to the spigot 2 and at right angles to the spigots 3 and 8. In the embodiment of Figure 6, a rurrner arm ana associated, spigot 10 extends in a direction mutually perpendicular to the spigots 2,3 and in the case of the embodiments of Figures 7,8 and 9, additional arms and associatedspigots 11,12 and 13 are provided as clearly shown in the respective figures. The connecting members of Figures 3 and 4 are the most commonly used for the construction of furniture frames and a typical table having a supporting frame embodying the invention .is shown in Figures 10 and 11. It will be noted from Figure 11 that the table, of Figure 10 is intended to be constructed from a kit of frame components .comprising nine tubes 6, four right angle connectors 1A and two T- connectors IB as well as a table top T having sockets S adapted to receive the ends of the leg tubes 6. It will be appreciated from the above description that by virtue of the provision of the co-operating grooves 4 in the spigots and the splines 7 in the frame tubes 6 that the connecting members 1A and IB will be accurately located orthoganally in the frame at the time of adhesively securing the connecting members to the tubes so that accurate location of the leg tubes 6 in the sockets S will occur. As mentioned above, the frame components are not limite to use in constructing furniture frames and may be used for example in shop display frames, storage racks and the like. Where further structural rigidity is required, a connecting member having an arm and associated spigot extending 45° to one of the existing arms and spigots may be provided whereby a bracing member may be inserted in the frame. For similar reasons the grooves 4, or additional similar grooves, may be arranged at 45 intervals to enable right angle connectors to extend at 45 for bracing purposes. f OMPI

Claims: 1. A set of frame components comprising a plurality of generally elongate hollow members of generally symmetrical cross-section and a plurality of connecting members each having at least two spigots extending therefrom and dimensioned to be received in said hollow members, each said spigot having at least one longitudinal groove or spline in its outer surface disposed at a predetermined angular relationship to the remainder of the connecting member, and said hollow members each having a longitudinal spline or groove formed internally thereof and dimensioned to co¬ operate with the or each groove or spline in said spigots. 2. The set of frame component of claim 1, wherein each spigot is formed with four grooves or splines arranged at 90 to each other about the periphery of the spigot and aligned with a predetermined directional axis of the connecting member. 3. The set of frame component of claims 1 or 2, wherein the outer configuration of the elongate hollow members is preferably the same as the outer configuration of the connecting members at a position adjacent the spigots. 4. The set of frame, component of claims 1,2 or 3, wherein said hollow members are tubular and said connecting members have tubular terminal portions of similar dimensions. 5. The set of frame component of claims 1,2,3 or 4, wherein the spigots of said connecting members are arranged orthogonally to each other. 6. A set of frame components substantially as described with reference to Figures 1 to 9 of the accompanying drawing 7. A frame comprising a set of frame components as defined in any of the claims 1 to 6 assembled with said spigots engaging said hollow members with said splines engaging said grooves to connect said frame,-components in a predetermined assembly. 8. A frame substantially as described with reference to Figures 10 and 11 of the accompanying .drawings. 9. A kit of parts for constructing a frame comprising a set of frame components according to any one of claims 1 t OMPI 6 * together with a set of suitable instructions as to their assembly . 10. A kit substantially as described with reference to Fig. 11 of the accompanying drawings. OMPI

Inventors: BALLIS JOHN HARLOW, BALLIS, JOHN, HARLOW
Applicants: POLYMOD AUSTRALIA PTY LTD, POLYMOD AUSTRALIA PTY. LTD.
Application year: 1983
Main classification: F16B12
IPC codes: F16B7, F16B12