GB2250793A

GB2250793A - Forming lateral joints between members of complex section

Info

Publication number: GB2250793A
Application number: GB9019779A
Authority: GB
Inventors: Anthony Brockman
Original assignee: Universal Components Ltd
Current assignee: Universal Components Ltd
Priority date: 1990-09-10
Filing date: 1990-09-10
Publication date: 1992-06-17
Anticipated expiration: 2010-09-10
Also published as: GB9019779D0; GB2250793B

Abstract

Elongate members 10 are joined to an elongate bar 12 at pre-determined angles, the members 10 and the bar 12 having a cross-section including first and second portions of different widths, by forming the elongate members 10 as two sub-sections connected together for relative sliding movement, and by forming the elongate members 10 with end-faces inclined at the appropriate angle, so that each sub-section can be displaced relative to the other to bring each sub-section into lateral abutment with one of the first and second portions of the bar 12, prior to securing the joint. This method is suitable for forming a joint between a jack rafter and a hip bar of a roof, e.g. the roof of a conservatory. <IMAGE>

Description

"LATERAL JOINTS BETWEEN ELONGATE MEMBERS" This invention relates to the formation of lateral joints between elongate members such as the rafters of a roof. More particularly, but not exclusively, the invention is applicable to the formation of a lateral joint between the so-called jack rafter and a hip bar of a conservatory roof formed of extruded aluminium sections.

When it is required to form lateral joints which may either be square or angled, it is necessary to cut one section transversely at the required angle to the longitudinal axis. Additionally, however, when, as is usually the case, the hip bar has a crosssection including a flange portion and a web portion, the cut in the jack rafter has to be stepped to accommodate the flange, and this is a complex operation.

In accordance with the present invention, we propose a method of forming a lateral joint at a pre-determined angle between elongate members, one of which has a cross-section including first and second portions of different widths, wherein the other elongate member is formed to include (in cross-section) two subsections connected together for relative sliding movement in the direction of the longitudinal axis of the member, wherein the said other member is formed with an end-face inclined at the appropriate angle, and wherein the sub-sections are displaced relative to one another to bring each sub-section into lateral abutment with one of the said portions of the said one member, prior to securing the joint.

Also, according to this invention, and in a preferred embodiment thereof, an extruded section for forming lateral joints with another member having first and second portions of different widths, comprises a first sub-section and a second sub-section connected, or for connection to, the first sub-section for relative sliding movement therewith in the direction of the longitudinal axis of the sub-sections.

When, as in the example referred to above, it is required to form a lateral joint between a jack rafter and a hip bar having a base flange for supporting a glazing panel, or the like, and an upstanding narrower web, the jack rafter can be formed by making a single cut at the required angle and the upper sub-section advanced by sliding relative to the lower sub-section, into lateral abutment with the web, leaving the lower sub-section in abutment with the base flange, both at the same angle.

In a preferred embodiment, the two sub-sections are slidably connected together by means of a head and neck (preferably a Tshaped) connector on one sub-section for insertion in an undercut groove or channel in the other sub-section. It will be understood that two or more such slidable connections may be provided depending upon the cross-sectional geometry of the member which in practice is generally another extruded section, with which the lateral joint is to be formed.

One embodiment of this invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a traditional conservatory construction; Figure 2 is a perspective view to an enlarged scale of a lateral joint between a jack rafter and a hip bar; Figure 3 shows the cut end of the jack rafter in the conventional lateral joint shown in Figure 2; Figure 4 is a cross-sectional view of the two sub-sections that make up a jack rafter for forming a lateral joint in accordance with the present invention; and Figure 5 is a cross-sectional plan view of a lateral joint formed in accordance with the present invention.

In the conservatory construction of Figure 1, a jack rafter 10 is joined to a hip bar 12 which itself comprises an assembly of extruded aluminium sections, by a lateral joint such as illustrated in Figure 2. Figure 3 illustrates how the jack rafter is cut transversely to the longitudinal axis thereof, at the required angle a, so as to form a step of length L which in the assembled position (Figure 2) will accommodate the flange portion 14 of the hip bar 12, allowing the jack rafter 10 to abut the hip bar 12 both in the region of the flange 14 and against the upstanding web 16.

By use of a jack rafter in accordance with the present invention, such as shown in Figure 4, the need to provide a stepped mitred end is avoided. The jack rafter is formed by connecting together two separately formed extruded aluminium sections 20,22 as illustrated. The lower flange sub-section 22 has an upstanding stub 24 with a T-section head 26 for insertion from one end thereof in a complimentary undercut groove 28 formed in the web portion 30 of the upper sub-section 20. This head and neck connection between two sub-sections firmly secures the two sections together permitting only relative sliding movement in the direction of the longitudinal axis of the section.

To form a lateral joint in accordance with the present invention, a cut is made at the required angle through the entire height of the jack rafter, that is to say, through both sections in the same plane. The mitred end is then offered transversely to the hip bar until one sub-section, in this case the lower subsection, is brought into abutment with a portion of the hip bar, in this case, the base flange. The upper sub-section 20 is then displaced in the direction of the longitudinal axis relative to the lower sub-section 22 until the mitred end of that subsection abuts the upper web portion 16 of the hip bar 12 as shown in Figure 5. In this position the joint is secured.

It will be understood that the joint may be secured in any convenient manner for example using a screw passing through the jack rafter into the hip bar as shown in Figure 2.

Alternatively, an angled bracket 32 may be attached by screws 34 on the one hand to the upper web portion 16 of the hip bar 12 and on the other to web 30 of the jack rafter 10 as shown in Figure 5 which is a cross-sectional plan view taken through the web 30 of the jack rafter at a level indicated by arrows AA in Figure 4.

Claims

1. A method of forming a lateral joint at a pre-determined angle between elongate members, one of which members has a crosssection including first and second portions of different widths, wherein the other elongate member is formed to include (in crosssection) two sub-sections connected together for relative sliding movement in the direction of the longitudinal axis of the member, wherein the said other member is formed with an end-face inclined at said pre-determined angle, and wherein the sub-sections are displaced relative to one another in said longitudinal direction to bring each sub-section into lateral abutment with one of the said portions of the said one member, prior to securing the joint.

2. A method according to claim 1, wherein the said other member is a jack rafter having upper and lower sub-sections and the said one member is a hip bar having a base flange for supporting a glazing panel, or the like, and an upstanding narrower web, wherein the jack rafter is shaped by making a single cut at the predetermined angle and the upper sub-section of the jack rafter advanced by sliding relative to the lower subsection, into lateral abutment with the web of the hip bar, leaving the lower sub-section in abutment with the base flange, both at the same angle.

3. An extruded section for forming a lateral joint with another member having first and second portions of different widths, said extruded section comprising a first sub-section and a second sub-section connected, or for connection to, the first sub-section for relative sliding movement therewith in the direction of the longitudinal axis of the sub-sections.

4. An extruded section according to claim 1, wherein the two sub-sections are slidably connected together by means of a head and neck connector on one sub-section for insertion in an undercut groove or channel in the other sub-section.

5. An extruded section according to claim 4, wherein the head and neck connector is T-shaped.

6. A method or extruded section substantially as described herein with reference to the accompanying drawings.