AU652485B2

AU652485B2 - An improved panel profile

Info

Publication number: AU652485B2
Application number: AU26243/92A
Authority: AU
Inventors: James Matthew Jansen
Original assignee: Stratco Australia Pty Ltd
Current assignee: Stratco Australia Pty Ltd
Priority date: 1991-10-04
Filing date: 1992-10-06
Publication date: 1994-08-25
Anticipated expiration: 2012-10-06
Also published as: AU2624392A

Description

a ua~mram~h~-m~ I 652 85 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

r cc o~rrr rre~ Ilv o o D o oo a Oo* o, a o~ r o a o oo ro~r ~c oo o** o r rr rr o~ o Name of Applicant: STRATCO (AUSTRALIA) PTY. LIMITED Actual Inventor: JAMES MATTHEW JANSEN Address for Service: R K MADDERN ASSOCIATES, 345 King William Street, Adelaide, South Australia, Australia Invention title: AN IMPROVED PANEL PROFILE Details of Associated Provisional Application No: PK 8720 dated 4th October, 1991.

The following statement is a full description of this invention, including the best method of performing it known to us.

This invention relates to an improved panel profile, and in particular relates to a panel having interlocking edges that is designed to resist unclipping of the edges under normal loads.

Panel sheeting or decking is produced with a great variety of profiles. The profiles vary from simple corrugations to channel sections having interlocking edges.

Such decking profiles are normally produced using roll forming techniques, and are produced in set widths and can be produced in varying lengths.

Such decking or sheet panels have a variety of applications, but normally are used in relation to roofing members. In order to produce a weatherproof joint, such decking panels are normally provided with either overlapping edges, or the edges are formed so that adjacent panels clip together.

In order to form a joint, each edge of a panel is provided with, on one edge a male or inner edge portion, and S on the other side a female or outer edge portion. Therefore, adjacent panels can be interlocked by engagement of the inner and outer portions.

Normally, the inner and outer edge portions comprise in "o cross-section an upstanding channel, and the outer edge eve.

portion is designed to overlap the inner edge portion.

Normally, the outer edge portion is designed to resiliently 30 deform thereby resulting in a joint, which, once forced together.

Although under normal light loads, such clipping eel..

arrangements are satisfactory, it has been found that higher loads which are applied perpendicularly to the surface of the sheeting causes buckling and unclipping of the joints. This unclipping tends to occur at relatively light loads, and obviously if the join lines could remain clipped, then much higher loads could be withstood by the assembled panels.

-2- Such known edge joints for panels have previously always been asymmetric about a vertical centre line. It is due to this asymmetry which results in the buckling of the joint when normal forces are applied.

This buckling and resultant unclipping is due to torsional forces along the joint which result from forces applied perpendicularly to the assembled panels.

Generally, when shear stress is distributed across a cross-section, the resultant force will act through a vertical line in the cross-section. This line or point on the cross-section is known as the shear centre, and the shear centre does not coincide with the centroid of the crosssection other than when the cross-section is symmetrical about a vertical line. Therefore, the resultant shear force which acts through the shear centre produces a bending moment about the centroid, which results in a torsional force being applied to the section.

In known examples of edge joints for panels, it is this asymmetry and resulting torsional force which causes buckling S. and unclipping of the joint.

25 Therefore, by making the respective portions of the edge oe 4 joints so as to form an assembled joint which is symmetric about a vertical line, the torsional forces can be eliminated or reduced so as to prevent buckling and unclipping of the r joint when forces are applied perpendicularly to the panel.

This then results in assembled panels being able to withstand significantly increased forces.

4 Therefore, it is an object of this invention to provide interlocking edge portion cross-sectional shape that is less likely to unclip as a result of perpendicular forces applied to assembled panels.

L~ i -i ec- I In another aspect of this invention, it is a requirement that any assembled panels be aesthetically pleasing in their appearance. In respect of sheet metal panels which are used for carports or garages, it is not normal to provide any lining on the underneath surface of the panel. Therefore, it is desirable that the panel have a uniform and aesthetically pleasing appearance when viewed from underneath.

This has not normally been possible with some sheet metal sections. This is particularly so in relation to panels which are formed into channel-like sections where a pair of channels are formed to produce a single sheet. The channels are normally defined by the edge locking portions, and a single rib that runs through the centre of the panel.

The central rib comprises a substantially U-shape crosssection, and obviously when viewed from underneath there is a somewhat irregular pattern formed as a result of difference in spacing between adjacent sheets when clipped together. In particular, there is a difference of appearance between the gap at a clip compared to the gap at a central rib.

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.4 44 4 0 4 444 4 '4 4449 4044 4 4 4440 Further, any minor reinforcing corrugation or ribs which may be formed in the panel between the rib and adjacent edge may not match the appearance of gaps between adjacent edges and the gap formed by the central rib. Therefore, when viewing several assembled sheets from underneath, a somewhat haphazard pattern is observed.

Therefore, it is a further object of this invention to provide a panel profile which has a more aesthetic appearance when viewed from underneath the assembled panels.

In its broadest form, the invention comprises a panel having locking edge portions arranged on two of the opposed edges of the panel which are adapted to connect in interlocking fashion, and stiffening channels formed in the panel between said locking edge portions extending parallel to said edge portions, said locking edge portions comprising '1) r o an outer locking edge portion on one side of the panel having a channel-shaped cross-section, and an inner locking edge portion on a side of the panel opposed to the outer locking edge portion having a channel-shaped cross-section that locates within the outer locking edge portion of an adjacent panel such that the inner locking edge is held with respect to the outer locking edge portion so that the edges of adjacent panels abut, the interlocking inner and outer edge portions of adjacent panels having a cross-sectional shape which is symmetric about a vertical axis that extends between the edges of adjacent panels, and said abutting edges shaped to form a channel having substantially the same crosssectional shape as said stiffening channels.

This results in a more uniform and aesthetically pleasing appearance when assembled sheets are viewed from o 0 8 underneath. Although a more pleasing visual appearance is 8888 produced, the strength properties of the assembled profile is 8 not reduced significantly.

In order that these and other aspects of this invention 888 0 may be readily understood, a preferred embodiment will now be described, however it should be realised that the invention :888.: is not to be confined or restricted to the precise details of 8 250 this embodiment.

This embodiment is illustrated in the accompanying diagrams in which: Fig. 1 shows an end view of a panel, Fig. 2 shows a perspective view of a panel, and Fig. 3 shows a cross-sectional view of interlocked adjacent edge portions.

In this embodiment, the panel is formed in continuous lengths from sheet steel. The sheet steel may be provided with coloured surfaces or may simply be galvanised.

As seen in the profile or end view of the embodiment, each edge is formed with a substantially channel-shaped portion. On one edge is formed an inner locking edge portion or inner edge portion 11 and on the other adjacent edge is formed an outer locking edge portion or outer edge portion 12.

The panel is formed with a central stiffening rib 14, and a plurality of stiffening channels 15. The stiffening rib 14 is substantially U-shaped in cross-section, but it will be seen that the base portion of the stiffening rib 14 is formed such that the sheet material is brought together along the length of the stiffening rib 14, and that the portions of the panel 14a are formed with the same crosssectional shape as the adjacent stiffening channels 15. When 120 viewed from underneath, the lower portions 14a of the go stiffening rib 14 will have the same appearance as the Sadjacent stiffening channels As can be seen from the end view, the outer edge portion 12 is formed so that some deformation of the channel is required to engage the inner edge portion 11. The outer edge portion 12 must elastically deform about or adjacent to the o edge 16, and the force associated with this deformation will also cause the inner edge portion 11 to likewise deform resulting in elastic deformation about or adjacent to edge aoo 17. The extent of deformation of both the inner and outer edge portions 11 and 12 will be within the elastic range, and as the surface 18 of the outer edge portion 12 passes over the edge 17 of the inner edge portion 11, the outer edge portion 12 will clip and lock to the inner edge portion 11.

As can be seen in the embodiment, both the inner and outer edge portions 11, 12 are formed with a vertical surface portion 20, and an angled surface portion 21. The inner and outer edge portions 11 and 12 are formed such that the vertical surfaces 20 of adjacent sheets abut, so that when viewed from beneath the assembled panels, the angled surface portions 21 have a cross-sectional shape similar to the stiffening channels 15. Therefore, it will be difficult to discern any difference between the stiffening rib 14, the join line between adjacent panels and the stiffening ribs This will result in a more aesthetically pleasing appearance.

In addition, it will be seen from Fig. 3 that when assembled, the inner and outer edge portions 11 and 12 have a substantially symmetrical cross-section about a central vertical axis y-y extending between the abutting panels.

There may still be minor variations in shape between the inner and outer edge portions 11 and 12 which result in a slight asymmetry however it is possible to vary the distribution of material such that the shear centre 25 is at least located over the central vertical axis y-y. This thereby avoids any torsional forces resulting from shear 20 loading across the joint, which in turn reduces buckling and S the tendency to unclip the inner and outer edge portions 11 and 12.

From a brief consideration of the above detail, it will be clear that the invention provides an improved panel profile with increased strength characteristics, and in a 44 addition the possibility of having improved appearance of the S* assembled panels when viewed from underneath.

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Claims

3. A panel according to any one of the preceding claims wherein the channel of the outer locking edge portion is shaped so as to elastically deform when it is forced over the inner locking edge portion, the inner and outer locking edge portions being shaped so that said outer portion locks onto said inner portion.
4. A panel according to any one of the preceding claims further comprising a stiffening rib formed between the inner and outer locking edge portions, said rib having substantially the same cross-sectional shape as the cross- sectional shape of the interlocked inner and outer locking edge portions, -8- hh :i A panel according to any one of the preceding claims wherein the stiffening channels have an inverted V-shape in cross-section, and the edge of each panel having an angled surface portion and a vertical surface portion below each said inner and outer edge portion, that when brought together form a V-shaped cross-sectional shape.
6. A panel substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings. Dated this 4th day of May 1994 STRATCO (AUSTRALIA) PTY LIMITED By its Patent Attorneys R K MADDERN ASSOCIATES. 0 0 0 0 0J 0 0
09- ABSTRACT This invention relates to an improved panel profile and in particular to a panel having interlocking edges that are designed to resist unclipping under normal loads. The invention comprises a panel having locking edge portions (11, 12) that are arranged on two of the opposing edges of the panel. The are adapted to connect in an interlocking fashion. A first edge portion comprises an inner locking edge (11) which has a channel-shaped cross-section that locates within an outer locking edge portion (12) of an adjacent panel such that the inner locking edge (11) is held with respect to the outer locking edge portion The interlocking inner and outer edge portions (11, 12) of adjacent panels have a cross-sectional shape which is symmetric about a vertical axis that extends between the edges of adjacent panels. The advantage of this symmetrical shape is that the shear centre will be located over the central vertical axis. This avoids any torsional forces being applied to the joint which would result from normal shear loading that is applied to the panels. 0 t 4 i 1 i 4 44t I rrr I t) i L i