GB2064055A - Tube joint - Google Patents

Abstract

Aligned tubes 1, 1a are joined by a tubular spigot 2 which can be expanded by means of a wedge 5 driven into a longitudinal slot in the spigot. The spigot carries a central ring 3 having ribs 9 for supporting cross-members 10. The wedge is operated by a bolt 5. <IMAGE>

Description

SPECIFICATION Expansion joint The present invention relates to an expansion joint provided with fastenings for connecting tubular elements disposed in end-to-end relation.

The invention more particularly relates to an expansion joint which is an improvement of that described and claimed in Italian Patent 960 155, filed on May 4th 1 972 by the present Applicant.

Thus, the preferred, but not exclusive use of the present invention is in the joining together of tubular elements of assemblable latticeworks and structural frames, particularly used as frames for exhibiting articles and as so-called displays in department stores and supermarkets.

The expansion joint described in the aforementioned Italian Patent solved the problem of providing a particularly stable connection of tubular elements which, for aesthetic reasons, required that the joint in no way interrupted the continuity of the lines of the connected tubular elements. This problem is particularly noticeable, for example, in the aforementioned case of display frames in general, as well as glass windows or show cases, no matter whether they are used indoors or outdoors.

However, it was found that while the aforementioned expansion joint was suitable for joining elements in the longitudinal direction, it could not be used on transverse elements extending radially with respect to the tubular eiements such as e.g. platforms, consoles, etc.

In order to be able to construct cross-members by means of the above joint it is necessary to use special multiway tubular connecting members, known in the art as T-joints and which comprise a plurality of tubular segments, forming a predetermined angle to one another and which are combined into a single member.

However, the use of such joints obviously increases the cost of a structure obtained in this way, either through the actual joints being expensive, or through their requiring the use of additional expansion joints, whose coat is added into the final cost of the structure.

A further disadvantage is due to the fact that such T-joints only permit a limited number of arrangements of transverse elements, due to the limited number of segments.

According to the present invention, there is provided an expansion joint for tubular elements comprising: a C-shaped socket adapted to be inserted over approximately half its length into the interior of the end of a first tubular element to be joined to a second tubular element; and a wedge arranged within the socket for widening the opening of the C-shape, an element operable from the outside being provided and serving for moving the wedge against the circumferential ends of the C-socket for widening the opening of the C-shape, the C-socket being wedged within a ring wherein on the outside of said ring there are radially projecting longitudinal ribs suitable for using and fixing connecting cross-members, projecting in use substantially radially from the joined tubular elements.

As will be apparent from the following description the illustrated embodiment of the invention can obviate ali the aforementioned disadvantages. It is particularly intended to obviate the use of Tjoints, because it is provided with suitable means for fixing cross-members.

Another feature of the illustrated expansion joint is that it permits a virtually unlimited number of cross-member arrangements, so that in this way the shape of the structure can be modified at random.

The invention also provides a jointed structure comprising a pair of tubular elements disposed in end-to-end relation and joined by means of an expansion joint according to the invention therebetween, and having respective ends of its C-shaped socket inserted in the facing ends of the two tubular elements and being urged thereagainst by said wedge.

The features and advantages of the expansion joint according to the present invention can be gathered from the following detailed description of a non-limitative embodiment and with reference to the accompanying drawings, in which: - Figure 1 is a cross-section through an embodiment of the expansion joint along the line I-I of Figure 2 and at right angles to the axis of the elements to be joined.

Figure 2 is a longitudinal section along the line Il-Il of Figure 1.

Figure 3 is a disassembled view of the joint, tubular elements and end of a cross-member to be fixed to the joint.

Figure 4 is a plan view of the use of a joint according to the invention.

Figure 5 is a diagrammatic perspective view of a use of the joint according to the invention.

For reasons of clarity and with particular reference to Figures 1 and 2 part of the joint which is not essential to the invention will now be described and in fact details thereof have already been described in the aforementioned Italian Patent specification.

According to the drawings the expansion joint has a C-shaped socket 2 on to which is centrally wedged a ring 3 for the purpose of joining together two tubular elements 1. From one end socket 2 is pressed into the interior of one of the tubular elements, for example element 1, until ring 3 comes into contact therewith. On the generatrix diametrically opposite to the C-socket opening there is a passage 4 which passes through the centre of ring 3, as well as through the underlying area of socket 2.

A metallic element 5 in the form of a wedge is mounted in socket 2 along the diameter defined by the opening of C-socket 2 and passage 4.

Wedge 5 is prevented from rotating within socket 2 by one of its ends being provided with teeth in order to adapt to the two open ends of the socket, whilst the other end is located within a recess (not shown) provided in socket 2.

A screw bolt with polygonal inner edges is introduced into the passage 4 and normally holds the wedge 5 in position which, corresponding to bolt 6, has a recess 7 facing the end of bolt 6. The latter rotates within a nut 8 engaged on the walls of recess 7 and preventing longitudinal movements of wedge 5. By tightening bolt 6 by means of a suitable box spanner wedge 5 is driven against the open ends of socket 2 which it widens and consequently increases the pressure exerted on the inner walls of the two tubular elements.

As can be seen in Figure 1 socket 2 is also provided with teeth in order to be able to receive nut 8 and the two ends of the C-shape are chamfered in order to facilitate the wedging of the end of wedge 5 bent in the same way. Preferably on its outer contact face with the tubular elements 1, 1 a and ring 3 socket 2 has longitudinal recesses interrupted by prismatic projections, facilitating the adaptation and wedging of said socket within elements 1, 1 a at ring 3.

Referring to Figure 3, as well as Figures 1 and 2, ring 3 comprises a body, whose outer part has a substantially polygonal shape (in the present case octagonal) having a longitudinal rib 9 in the central portion of each face. In the present embodiment the longitudinal rib is crosssectionally dove-tailed, but it is obvious that any other suitable shape can be used, provided that it is suitable for introducing and locking the end of a crossmember.

It is apparent from Figure 3 that cross-member 10 has an end suitable for fixing to ring 3 and which is toothed in a manner corresponding to the longitudinal ribs. For this purpose the end of the cross-member has a coupling member fitted thereto or constructed in one piece with the crossmember and which in corresponding, not shown, manner is toothed in order to permit connection to longitudinal rib 9. The end of cross-member 10 is open at the bottom and closed at the top, in such a way that the upper edge 12 engages against the corresponding end of longitudinal rib 9.

It can be more particularly gathered from Figure 4 that the outer faces of ring 3 are suitable for making the anchoring of cross-member 10 particularly stable and consequently prevent transverse displacement of the latter.

A first embodiment of the joint according to the invention can now be described relative to Figure 4 in which, for reasons of simplicity, ring 3 is shown without the socket and its locking means.

In Figure 4 five cross-members 10 are provided on ring 3 and are arranged in random circular manner around the latter. The two cross-members 10 on the right-hand side, which substantially form a V-shape, are intended to carry a contact surface 14. for example of glass, by means of known brackets 13 fitted thereto. A similar contact surface 1 5, for example of wood, is formed in the same way by the left-hand horizontal cross-member and the vertically lower cross-member in the drawing. The remaining upper cross-member 10 can be used to support supporting elements for articles to be displayed or merely for displays.

Figure 5 shows a second embodiment of the joint according to the invention. Only the ring 3 for the various joints to be used is visible in Figure 5, but the structure comprises two supports 1 6, having a substantially inverted U-shaped configuration and connected at the bottom by two base struts 1 7. At the top, supports 1 6 are joined by means of cross-members 10 fitted by their ends to rings 3.

At the lower end of one of the supports 1 6 a first cross-member 10 is provided, permitting by means of a further upper cross-member 10 the mounting of a stop plate, e.g. of glass.

It is obvious that the structure obtained in this way, which is similarly closed at the opposite end face by another plate, can advantageously be used as a display frame for articles.

Obviously variants and/or modifications to the expansion joint are possible within the scope of the invention as defined in the appended claims.

Thus, for example, the number of longitudinal ribs 9 can be varied compared with the present embodiment in which 8 are provided. This may obviously be carried out in accordance with the specific requirements made on the structure obtained.

The shape of the longitudinal ribs can also be modified, particularly their cross-section and this leads to the modification of the end of the crossmember to be connected.

Finally it is clear and as described in the aforementioned Patent specification that the material from which the socket is made is preferably softer than that of the tubular elements. For example an aiuminium socket can be used for steel pipes.

Claims (7)

1. An expansion joint for tubular elements comprising: a C-shaped socket adapted to be inserted over approximately half its length into the interior of the end of a first tubular element to be joined to a second tubular element; and a wedge arranged within the socket for widening the opening of the C-shape, an element operable from the outside being provided and serving for moving the wedge against the circumferential ends of the C-socket for widening the opening of the C-shapd, the C-socket being wedged within a ring, wherein on the outside of the said ring there are radially projecting longitudinal ribs suitable for using andfixing connecting cross-members, projecting in use substantially radially from the joined tubular elements.

2. An expansion joint according to claim 1, wherein the ring has a polygonally shaped cross section, the longitudinal ribs being arranged substantially in the central portion of each face of the polygonal shape.

3. A jointed structure comprising a pair of tubular elements disposed in end to end relation and joined by means of a joint according to claim 1 or 2 therebetween and having respective ends of its C-shaped socket inserted in the facing ends of the two tubular elements and being urged thereagainst by said wedge.

4. A structure according to claim 3 and including at least one cross member extending substantially radially from the ring and having a complementarily shaped end portion fitted to one of the ribs of the ring.

5. A structure according to claim 3 or 4 wherein the tubular elements and the ring of the joint have substantially equal outer diameters.

6. An expansion joint constructed and arranged substantially as herein described with reference to and as illustrated in Figures 1, 2 and 3 of the accompanying drawings.

7. A jointed structure constructed and arranged substantially as herein described with reference to and as illustrated in Figures 3, 4 and 5 of the accompanying drawings.