GB2307535A

GB2307535A - Joints for metal sections

Info

Publication number: GB2307535A
Application number: GB9624088A
Authority: GB
Inventors: Mark Billing
Original assignee: Voestalpine Metsec PLC
Current assignee: Voestalpine Metsec PLC
Priority date: 1995-11-22
Filing date: 1996-11-20
Publication date: 1997-05-28
Also published as: GB9624088D0; GB9523880D0

Abstract

A joint-comprising a first metal L-section frame member (10) and a second metal L-section frame member (12), the first and second members each including an angled end wall (14) arranged to abut the angled end wall (14) of the other member, and wherein the end wall of the first member is provided with a projection (16) arranged to be received in a respective recess (18) provided in the end wall of the second member to correctly position the members with respect to one another. The projection (16) and the recess (18) are remote from the junction between web and flange. The first and second members (10, 12) are formed with angled end walls (14) simultaneously by a single cut from a continuous length.

Description

JOINT This invention relates to a joint, and in particular to a mitred joint for forming, for example, a frame constructed of cold rolled steel or other metal section members, and to a frame incorporating one or more of such joints.

Frames constructed of cold rolled metal sections often have mitred corners in which, once the adjacent metal sections are correctly aligned, the metal sections are welded to one another.

Figure 1 illustrates a known arrangement for ensuring that the metal sections align with one another, Figures 2 and 3 illustrating the two metal section members 1, 2 used in the joint of Figure 1. Each of the members 1, 2 shown in Figures 1 to 3 is of L-shaped cross-section including a web la, 2a, and an upstanding flange 1k, 2h. As shown most clearly in Figures 2 and 3, the webs la, 2a each have an angled end surface 3, the end surfaces 3 being angled at 450 to the longitudinal direction of the respective member 1, 2 such that when the end surfaces 3 abut, the members 1, 2 together form a right angle.

The upstanding flange ib of the member 1 extends beyond the end of the web la thereof by an amount equal to the flange thickness. The flange 2h of the member 2 terminates at a position aligned with the end of the respective web 2a, and it will be recognised that when the members 1, 2 are correctly positioned with respect to one another, the end of the flange 2k abuts the side face of the projecting part of the flange ib.

Although such an arrangement facilitates alignment of two members forming a right-angled joint, it will be understood that it is difficult to manufacture the members, particularly the member 1 where it is necessary to cut the web along its junction with the flange to leave the projecting region of the flange.

According to the present invention there is provided a joint comprising a first metal section member and a second metal section member, the first and second members each including an angled end wall arranged to abut the angled end wall of the other member, and wherein the end wall of the first member is provided with a projection arranged to be received in a respective recess provided in the end wall of the second member to correctly position the members with respect to one another.

Where the first and second members comprise respective interconnected webs and upstanding flanges, the projection and recess are preferably provided in parts of the respective end walls remote from the web/flange junction.

The invention further resides in a metal frame incorporating one or more such joints.

The invention will further be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a conventional mitred joint arrangement; Figures 2 and 3 are perspective views of the components of the arrangement of Figure 1; Figure 4 is a perspective view of a mitred joint in accordance with an embodiment of the invention; Figures 5 and 6 are perspective views of the components of the joint of Figure 4; Figure 7 is a view of the underside of the joint of Figure 4; and Figures 8 and 9 are views of the underside of the components illustrated in Figures 5 and 6, respectively.

The joint illustrated in Figures 4 to 9 comprises a first and second components 10, 12 each formed from generally L-shaped cold rolled steel section including a web 10a, 12a and an upstanding flange lOb, 12b.

The first and second components 10, 12 are intended to form a right angled mitred joint; thus the web 10a, 12a and flange lob, 12b of each component 10, 12 is cut so as to define an end wall making an angle of 45" with respect to the longitudinal axis of the respective component 10, 12. It will be recognised that the angled end wall 14 extends through both the web 10a, 12a and the upstanding flange 10k, 12b of each of the components 10, 12.

In order to facilitate alignment of the components 10, 12, the end wall 14 of the first component 10 is provided with a projection 16, the projection 16 being provided adjacent the end of the end wall 14 remote from the flange lOb. A recess 18 corresponding in shape with the projection 16 is provided in the end wall 14 of the second component 12, the recess 18 and projection 16 being arranged such that when the components 10, 12 are aligned with one another, the projection 16 is received within the recess 18.

During construction of the mitred joint, the components 10, 12 are arranged such that the end faces 14 thereof abut one another, their relative positions being adjusted until the projection 16 is received within the recess 18. Once the projection 16 has been received within the recess 18, it will be recognised that the components 10, 12 are correctly aligned with one another as shown in Figures 4 and 7, and can be welded to one another in order to form a rigid structure.

Although the above description relates to a right angled mitred joint, it will be recognised that by providing the end surfaces 14 at other suitable angles, mitred joints having an angle of other than 90" may be provided.

It will further be recognised that although in the above description the projection 16 and recess 18 are provided adjacent an end of the end surface 14, the projection 16 and recess 18 may be provided at any suitable location along the length of the end surface 14 provided that when the projection 16 is received within the recess 18, proper alignment of the first section 10 with respect to the second section 12 is achieved.

In the described and illustrated embodiment, the projection 16 includes a pair of walls which define a right angle, the recess 18 similarly taking the form of a right angle V-shaped groove. It will be recognised that other shapes for the projection 16 and recess 18 may be used, for example, semi-circular projections and recesses. Moreover although in the above embodiments the web and flange of each section are disposed at right angles to one another, the invention could be employed in relation to L-sections or other sectional shapes where the web and flange are other than perpendicular.

The metal sections used in production of the mitred joint are commonly produced using a continuous process and it is envisaged that at least in relation to L-sections a cutoff tool could be used in such a process in order to cut the continuous section into lengths suitable for use in constructing a frame having mitred joints. The cutoff tool is arranged to cut the metal section in order to define an end surface 14 including a recess 18 on the trailing end of one metal section, and at the same time to cut an end surface 14 including a projection 16 on the leading end of the next metal section to be produced. It will be recognised that such a cut-off tool is arranged to cut a generally V-shaped region from the section being produced during the continuous cold rolling process.

Claims

1. A joint comprising a first metal section member and a second metal section member, the first and second members each including an angled end wall arranged to abut the angled end wall of the other member, and wherein the end wall of the first member is provided with a projection arranged to be received in a respective recess provided in the end wall of the second member to correctly position the members with respect to one another.

2. A joint as claimed in Claim 1, wherein said first and second members comprise respective interconnected webs and upstanding flanges, the projection and recess being provided in parts of said angled end walls remote from the web/flange junction.

3. A joint as claimed in Claim 1 or Claim 2, wherein said angled end walls extend at 45" to the length of the respective section whereby the sections are to be arranged at 90" to one another.

4. A joint substantially as hereinbefore described with reference to Figures 4 to 9 of the accompanying drawings.

5. A method of manufacturing a joint as claimed in any one of Claims 1 to 4 comprising cutting first and second metal section members from a substantially continuous length such that the first member has an angled end wall including a projection, and the second member has an angled end wall including a recess, said angled end walls being so angled that when in abutting relationship the section members lie at a predetermined angle to one another, abutting the angled end faces such that said projection is received in said recess, and, securing the members together.

6. A method as claimed in Claim 5, wherein said angled end walls of said first and second members are cut simultaneously by a single cutoff tool as one of said members is cut from said length.

7. A method as claimed in Claim 5 or Claim 6, wherein said members are secured together by welding.

8. A joint formed by the method claimed in any one of Claims 5 to 7.

9. A metal frame incorporating one or more joints as claimed in any one of Claims 1 to 4 and Claim 8.