GB2167489A - Connector for tubular frames - Google Patents

Abstract

A corner connector (3) comprises a base element (12) which can be screwed on to a continuous tubular bearers (4, 10), two clamping tenons (3', 3'') which are at right angles to one another in a common plane and which receive tubes (8) or tube portions projecting at right angles from the continuous bearer. Each of the clamping tenons (3', 3'') is provided with a conical spreader device (14, 15). Spreader slots (17, 18) are arranged crosswise round a conical bore (13), into which a tapered sleeve (14) can be drawn by means of a tensioning screw (15), and are formed in pairs opposite one another in the clamping tenons (3', 3''). The shank of the tensioning screw (15) is guided in an inner cylindrical portion (13'') of the centre bore (13), also containing the conical bore (13'), and is intended to pass through a fastening recess (16) in the continuous tube bearer (4, 10), in the inner wall of which the screw head (15') is supported. The spreader slots (17, 18) which are opposite one another in pairs and of which one is open inwards and the other outwards in the corner connector (3) guarantee that the tube end is clamped securely and uniformly over practically the entire length of each of the clamping tenons (3', 3''). <IMAGE>

Description

SPECIFICATION Connector for tubular frames This disclosure relates to a connector suitable for use in tubular frames, and in particular to a corner connector.

In the erection of tubular frames, it is known to use corner connectors in which tube ends can be attached to plug-in tenons and are fastened by means of rotary clamping or screwing. When these corner connectors are to be suitable for frames with high supporting loads, high lateral stresses or vibrations as a result of impact stress or alternating loads, clamping connectors pure and simple are of no use. This leaves, for preference, screw connectors in which a connection made by tightening one or more screws is obtained between the plug-in tenons and the connecting ends of the tube. Although such screw connectors can be made vibration-proof by means of relatively simple measures, screw heads are left projecting above the tube surface and retaining elements which have disadvantages in design terms and which have an unsatisfactory appearance.

Viewed from one broad aspect there is herein disclosed a connector for tubular frames comprising at least one clamping tenon secured to a base element and adapted for insertion into a tubular frame member, such tenon including a central bore having a slotted conical portion and wedging means including a tapered sleeve disposed within said conical portion, said sleeve having a threaded axial bore which is threadedly engaged with an axially extending tensioning element passing through said base element, the arrangement being such that rotation of said tensioning element causes axial movement of said sleeve relative to said conical bore which causes radial expansion of said tenon in the region of the slots into clamping engagement with a tubular frame member in use.

An embodiment of this broad aspect will now be described by way of example with reference to the accompanying drawings in which: Figure 1 shows an end part of a tubular frame with corner connectors according to this embodiment; Figure 2 shows a floor-standing supporting arrangement of an upright tubular frame; Figure 3 shows, on a larger scale, a frame junction point including a corner connector; Figure 4 shows a corner connector in an axial section, and Figures 5 and 6 show representations of the corner connector offset 90 relative to one another.

In the figures, the same reference symbols designate the same or identical components. Referring firstly to Figure 1, in the end part of a tubular wall frame base cross members 1 are connected to the two adjacent inwardly directed side faces 2 (only one of which is visible), of a corner column 4 which extends the entire height of the frame, by means of a corner connector 3 (indicated by broken lines). The corner column 4 is taken down to the base plane 5 at the place of erection, so that its bottom end 4' can form a supporting point for the frame. As can easily be seen, the corner connector 3 could, if desired, be arranged so that the undersides 1' of the base cross members 1 also rest on the base plane 5, with the result that at least the regions of these which are near the corner also contribute to forming a supporting point.

The corner column 4 is provided with apertures 6 which are arranged, for example, in a grid pattern and which allow fastening screws for the corner connector 3 and the associated tool to be introduced into the tube interior, as will be explained with reference to Figure 4. The tube profiles used for the base cross members 1 and the corner column 4 preferably have a square or rectangular cross-section, however other cross-sectional forms of the tubes can also be used, provided that the joining members of the corner connectors 3 are adapted accordingly.

The apertures 6, the height of which determine the connection points of the base cross members 1 and shelf- receiving or stabilising cross members 7, are located in the outer faces of the corner column 4, that is to say in those faces which are located opposite the connection points of the corner connector 3. Matching bores for a screw shank are provided in the inner faces of the corner column and will be described with reference to Figure 4.

Figure 2 illustrates a floor-standing supporting arrangement for an upright tubular frame, with four upright tubes 8 standing freely or in a structure inter-connected by means of cross members (not shown). As shown on a larger scale in Figure 3, each of the upright tubes 8 stands on a junction point 9. Each junction point 9 comprises a corner connector 3 (shown by broken lines) fastened to a continuous tubular bearer 10, the latter being divided into two portions 10' and 10" by the connection point of the corner connector. The portion designated by 10', functioning as an outer supporting arm of the supporting arrangement, is provided with a resting element 11. In contrast, the other portion 10" is connected to an adjacent junction point 9 by means of the horizontal tenon 3' (Figures 2 and 3) of a corner connector 3 which engages the interior of portion 10".In the floorstanding supporting arrangement shown in Figure 2, there are four such junction points 9, at which the details described are repeated in turn.

Figure 4 shows a corner connector 3 in section and in a state of preassembly on a continuous corner column 4 (Figure 1) or a continuous bearer 10 (Figures 2 and 3). Arranged on a L-shaped base element 12, the surface dimensions of which match the cross-sectional outer dimensions of the corner column 4 or continuous bearer 10 to be used and the cross member portions 1, 7 or upright tubes 8 to be connected, are tube-connecting clamping tenons 3', 3" with axes x-x and y-y which are perpendicular to one another and which lie in the same plane. As explained below, the clamping tenons 3', 3" are divided into four parts, but these are connected in one piece to the base element 12.

Each tenon comprises a centre bore 13 which is conical in an outer portion 13' and cylindrical in an inner portion 13". Located in each of the conical portions 13' are wedging means in the form of a tapered sleeve 14 which can be drawn into the conical portion 13' by means of a tensioning element such as a screw 15. The shank of the screw 15 passes through an inner aperture 16 in line with the outer aperture 6, and the heads 15' of the screws 15 rest against the inner wall of the column or bearer. The axial geometry and the dimensions of the screw heads 15' are co-ordinated with one another in such a way that, after one screw 15 has been tightened, the other can be inserted through the associated aperture 6 and likewise tightened.

To ensure that the tenon surface presses as uniformly as possible against the inner wall of the tube, the tube-connecting clamping tenons 3' and 3" are provided with spreader slots 17, 18 arranged crosswise relative to one another. A preferred form of slot arrangement is shown in Figures 5 and 6. in Figures 5 and 6, a corner connector is shown in two views which are at 900 relative to one another. In Figure 5, the spreader slots 17 first pass through the base element 12 from "inside" and divide the latter into two portions of approximately equal size. The spreader slots 17 end at a point before the outer tenon end 13"' and which is located far enough inwards to ensure the stability of the base element 12.In the assembled state of the corner connector 3, the tenons 3', 3" are surrounded by the walls of the associated tube ends, so that the outer portion of the base element 12 is prevented from drifting out when the screw 15 is tightened.

The spreader slots 18 shown in Figure 6 are open towards the tenon ends 13"' and terminate at a point 19 (see also Figure 5)1 to 2 mm from the base element 12, so that the spreader slots 18 also ensure the stability of the base element 12. The two paired spreader slots 17, 18 are in respective planes which are perpendicular to one another and in which the axes x-x and y-y of the tenons 3', 3" also lie.

When the tapered sleeve 14 is drawn inwards by means of the screw 15, the spreader slots 17, 18 open outwards and inwards respectively in each of the tenons 3', 3" and ensure that, the surfaces of the tenons 3', 3" come up against the opposite inner faces of the associated tube ends as effectively as possible and thus make a positive strong connection between the tubes connected at the junction point. To prevent the tapered sleeve 14 from rotating when the screw 15 is tightened, it is provided on its surface with axially directed engaging means preferably with centring wings 20 (Figure 4) which are located diametrically opposite one another and which are intended for engaging into the spreader slot 18 extending from the outer end inwards.The base element 12 divided in two by the spreader slots 17 is prevented from drifting out by the tube attached to it and is pressed firmly as a whole on to the surface of the continuous bearer by the screws 15.

It will be seen that, at least in a preferred embodiment, there is provided a corner connector for tubular frames, in which the advantages of a clamping connector, in particular the simple attachment of a tube end to be connected, can be combined with a vibration-proof screw connection between the corner connector and tubular frame, and at the same time, with the exception of stop portions between the tube surfaces and the supporting body of the corner connector, there are no connector components which project above the tube surface.

Modifications to the specific embodiments and to any broad aspects thereof referred to or suggested herein may be apparent to those skilled in the art and the disclosure hereof is intended to encompass any such modifications.

Claims (12)

1. A connector for tubular frames comprising at least one clamping tenon secured to a base element and adapted for insertion into a tubular frame member, such tenon including a central bore having a slotted conical portion and wedging means including a tapered sleeve disposed within said conical portion, said sleeve having a threaded axial bore which is threadedly engaged with an axially extended tensioning element passing through said base element, the arrangement being such that rotation of said tensioning element causes axial movement of said sleeve relative to said conical bore which causes radial expansion of said tenon in the region of the slots into clamping engagement with a tubular frame member in use.

2. A connector according to claim 1 wherein said connector is a corner connector and com- prises two tenons secured at right-angles to one another on a substantially L-shaped base element.

3. A connector according to claim 1 or 2 wherein each such tenon is formed with a pair of mutually perpendicular slots which each intersect said conical bore portion, one of said slots extending from the base element toward the outer end of the tenon terminating at a distance therefrom and the other of said slots extending from the outer end of the tenon towards the base element terminating at a distance therefrom.

4. A connector according to any preceding claim wherein said tapered sleeve is formed with longitudinal ribbing whereby, said sleeve is prevented from turning when said tensioning element is rotated.

5. A connector according to claim 4 wherein said ribbing comprises at least one centering wing engaging one of said slots.

6. A connector according to any preceding claim wherein said tensioning element comprises a screw which is adapted to pass through an aperture in a wall of a tubular frame member, the inner face of said wall adjacent said aperture forming the bearing surface for the screw, whereby said connector is fixedly secured to a tubular member by means of the screw upon tightening thereof to cause axial movement of the sleeve in use.

7. Corner connector for tubular frames, with two tube-connecting clamping tenons (3', 3",) arranged at right angles to one another in a common plane, and with a base element (12) which carries the two clamping tenons and which is intended to be fastened to a continuous corner column (4) or to a continuous bearer (10), the clamping tenons (3', 3") each being designed for the positive and non-positive coupling of a further tube to the corner column or to the continuous bearer and being provided with a conical spreader device (14, 15, 17, 18), characterised in that the conical spreader device of each clamping tenon (3', 3") comprises a taper sleeve (14), which can be drawn into an outer conical portion (13') of a centre bore (13) in the clamping tenon (3', 3") from the end (3"') of the clamping tenon by means of a tensioning screw (15), and a pair of spreader slots (17, 18) which are at right angles to one another in each clamping tenon and of which one (17) is formed so as to extend from the base element (12), severing the latter, towards the outer tenon end (3"') and the other (18) is formed so as to extend from the outer tenon end (3"') towards the base element (12), ending at a distance from the latter, and in that the shank of the tensioning screw (15) is guided in an inner cylindrical portion (13") of the centre bore (13), passes through the base element (12) and is intended to penetrate through a recess (16) in the adjacent tube-profile wall, the inner face of which is intended for forming the bearing points for the screw head (15').

8. Corner connector according to claim 7, characterised in that the clamping tenons (3', 3") are connected in one piece to the base element (12), and the latter has on the inside a plan which matches that of the further tube intended to be connected.

9. Corner connector according to claim 7, characterised in that the spreader slots (17, 18) are aligned in planes which are at right angles to one another and which coincide with the longitudinal axes (x-x, y-y) of the clamping tenons (3', 3").

10. Corner connector according to claim 7, characterised in that the taper sleeve (14) is provided with axis-parallel longitudinal ribbing as a means of preventing it from rotating.

11. Corner connector according to claim 7 or 10, characterised in that the taper sleeve (14) is provided with at least one centering wing (20) engaging into the spreader slot (18) open from outside inwards.

12. A connector for tubular frames substantially as hereinbefore described with reference to the accompanying drawings.