AU686146B2 - Concealed fixing - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT CONCEALED FIXING THE FOLLOWING STATEMENT IS A FULL DESCRIPTION OF THIS INVENTION, INCLUDING THE BEST METHOD OF PERFORMING IT KNOWN TO ME:- The present invention relates to a retaining clip construction for the concealed fixing of roofing or other cladding sheets.

Cladding sheets for concealed fixing have a plurality of longitudinal, re-entrant ribs, with pan sections between the ribs. The edges of the sheets are adapted for interengagement with the adjacent sheets, so that an end rib of one sheet fits over the end portion of the adjacent sheet.

The sheets are typically secured to the roof structure by elongated clips which secure the trailing edge end portion of the previously laid sheet and the leading edge rib and intermediate ribs of the sheet to be laid. The clip has retaining formations spaced along the length thereof to coincide with the rib spacing.

An endmost retaining formation of the clip is engaged with the trailing edge portion of the previously laid sheet, with the remainder of the clip extending in the direction of progress, and is fixed to the roof structure. The next sheet is then pressed onto the clip so that the leading edge rib and intermediate ribs are engaged with the retaining formations and the leading edge rib also locks over the trailing edge portion of the previous sheet.

The prior art clips are formed as a strap, which is folded to form a series of humps. The humps have -2detents for engagement with re-entrant portions of the ribs of the sheet. The clip is installed with the first hump positioned over the trailing edge rib of the previously laid sheet and the remainder of the clip extending in the direction of laying progress. The clip is then fixed to a purlin by fasteners passing through the clip beside the humps, and the next sheet is snap-fitted over the clip.

The present invention seeks to provide an alternative clipping arrangement.

In a first aspect, the present invention provides a cladding sheet and clip arrangement, the cladding sheet having spaced apart leading and trading edge regions and being arranged to be juxtaposed with a like cladding sheet with the leading edge region of one sheet overlapping the trailing edge region of the other sheet to form a longitudinal extending rib at said overlapping edge region, said leading edge region including a rib part and said trailing edge region including an upwardly facing shoulder and a distal edge having a downwardly turned lip, the clip arrangement including an elongate retaining clip having an endmost retaining formation including a pair of downwardly facing surfaces, said clip being adapted S: for partial insertion under said trailing edge of said sheet such that an endmost one of said downwardly facing surfaces locates in a retained position above the 20 upwardly facing shoulder of said trailing edge region, wherein said endmost retaining formation includes means for engaging said lip so as to retain said S'trailing edge region in said retained position and wherein when in said retained position, the other downwardly facing surface of the endmost retaining formation is free for engagement with the leading edge rib part of a like cladding sheet so 25 as to enable the overlapping edge regions to be secured to an underlying structure by said clip arrangement.

Preferably the leading edge rib part includes a pair of opposed re-entrant portions and wherein one of the re-entrant portions is adapted to locate under the shoulder of the trailing edge region of the like sheet and the other re-entrant por'k;n is adapted to locate below the free downwardly facing surface of the end most S. retaining formation.

CWNWCRDtSVONESYONEY16AF97 OCC -2a- Preferably the leading edge region is adapted to overlap in a snap fit engagement with the end most retaining formation and the trailing end region of the like sheet.

Preferably the lip engaging means of the endmost retaining formation includes a flange behind which the lip of the trailing edge region of the cladding sheet is adapted to be retained. Preferably the flange hooks under the lip of the trailing edge region in locating the trailing edge region of the cladding sheet in the retained position.

Preferably the end most retaining formation is adapted to be secured to an underlying structure when the trailing edge region is in the retained position.

In a second aspect, the present invention provides a method of fixing a plurality of cladding sheets to an underlying structure, the cladding sheets having at least one longitudinal extending rib and including a longitudinal extending leading and trailing edge, the leading edge being in the form of a rib part, the or each rib and rib part including an interior space bounded by opposing interior walls and the cladding sheets being fixed to the underlying structure by a clip incorporating a plurality of retaining formations locatable within the interior space of the 20 respective ribs and rib part, the method including the steps of: a) fixing a first cladding sheet to the underlying structure, the cladding .:.sheeting being fixed by a first retaining formation which is fastened to said underlying structure and which is in engagement with interior walls of a rib of said first cladding sheet; 25 b) interconnecting a second retaining formation to the trailing edge of the first cladding sheet the trailing edge of said first cladding sheet including a hooked edge and wherein said trailing sheet is interconnected with the second retaining formation by the hooked edge being located in a recess in an upper surface of said second retaining formation; c) fastening said second retaining formation having said trailing edge connected thereto to the underlying structure; and c, SNF -2bd) fixing a second cladding sheet to the underlying structure by locating the leading edge of the second cladding sheet over said second retaining formation and said trailing edge of said first sheet and bringing the interior walls of said rib part into engagement with said second retaining formation and said trailing edge of said first sheet.

Further preferred embodiments of the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a schematic perspective showing installation *e *o *o*o o al VR Y c) of a roofing sheet using a prior art clip; Fig. 2 is a plan view of a preferred clip in accordance with the present invention; Fig. 3 is a side view of the clip of Fig. 2; Fig. 4 is a perspective view of the clip of Fig. 2; Fig. 5A is a left hand end view of the clip of Fig. 2; Fig. 5B is a right hand end view of the clip of Fig. 2; Fig. 6 illustrates the cladding sheet profile for use with the clips of Fig. 2; Figs. 7A to 7D are schematic side views illustrating the installation procedure; and Fig. 8 is a detail side view of a retaining formation of the clip engaged with the leading edge rib of a sheet and the trailing edge portion of the previous sheet.

oloo e: e With reference to Fig. 1, the prior art fixing system includes a clip 10 consisting of a flat strap which has been folded along lines 900 to its length to form hump-shaped retaining formations lla,llb at its ends.

These formations have detents 12 therein to engage inside the female 13b and intermediate 14 ribs of the roofing sheets 15a,15b. In use, the first hump lla of the clip is positioned over the male rib 16a on the trailing edge of the previously laid sheet 15a, and the cli fixed to purlin 17 by screws at positions 18a aiiu ±8b. The second sheet 15b is then positioned with its female 13b and intermediate 14b ribs over the

~L,

-4respective formations Ila, llb and is pressed downwards to snap home over the detents 12 and to engage the female rib over the full length of of the male rib 16a. The procedure is repeated for subsequent sheets, with the male rib of the final sheet being held by a finishing clip.

Figs. 2 to 5 illustrate a preferred clip arrangement according to the present invention. The clip includes a strap 21 shaped for most of its length as a shallow, downwardly facing channel 22 (as best shown in Fig 5A). At point 23 the channel inverts to form an upwards facing channel 24 best shown in Figs. 4 and Three retaining formations 25 are attached to the strap, at positions corresponding to the leading Edge rib 26 and the two intermediate ribs 27 of the roofing sheet 28 of Fig. 6. Each retaining formation is formed as a generally channel-shaped element in end having a base 29 and a pair of opposed upright 0**t tabs 30 of a generally similar profile to tIAe rib.

"'"Each tab has a pair of downwardly facing shoulders 39 for location above the re-entrant portions 40 of the 25 rib, an inwardly turned longitudinal top flange 31 and a pair of inwardly angled longitudinal flanges 32.

The faces of angled flanges 32 are adapted to abut the inside surface of the rib. There preferably is some clearance of the top longitudinal flange 31 and the top of the rib, to allow the rib to flex while being snap-fitted onto the tab.

As illustrated in Figs. 7A to 7D, the first clip oe is secured to the purlin by fasteners 35 passing o 35 through the fastener holes 36 in the strap between the tabs of each retaining formation. Securing the clip also compresses the insulation blanket 41.

,---111 As shown in Fig. 7B, the roofing sheet 28a is aligned above the clip 20a and pushed downwardly to snap fit the top prortions of the ribs over corresponding barbed part of the tabs. Engagement between downwardly facing shoulders 39 of the tchs and opposed re-entrant parts 40 of each rib then prevent the sheet from being lifted out of engagement. The angled flanges 32 above the shoulders 39 fit tightly inside upwardly convergent top walls 42 of the rib to prevent twisting of the tab.

The next clip 20b is installed with the angled flanges 32 of the endmost retaining formation 25a hooking under the lip 43 of the trailing edge portion 33 of the previously laid roofing sheet 28a. The clip is pivoted downwards and secured to the purlin 34 by fasteners 35 passing through fastener holes 36 in the clip (Fig. 7C).

20 The next roofing sheet 28b is then aligned above clip 20b and snapped home as described above for roofing sheet 28a, except that the leading edge rib 26 snaps over both the endmost retaining formation 25a and the trailing end portion 33 of the previous sheet. The engagement between the two clips 20a,20b and the two sheets 28a,28b is described below with reference to Fig. 8.

Fig. 8 illustrates the overlap between two adjacent sheets. The trailing edge portion 33 is shaped as one side of a rib, including an upwardly facing shoulder 44 shaped like the re-entrant parts 40 of the ribs.

S. 55 e S• The shoulder 44 of the end portion is held down by the near shoulder 39 of the tab in the same manner as the ribs. The downwardly turned lip 43 at the outer edge of the trailing edge portion is hooked behind the ~s c endmost angled flange 32 of the tab to prevent the shoulder 44 of the edge portion and the shoulder 39 of the tab from moving laterally out of alignment.

The illustrated retaining formations and the manner of connection with the projecting edge portion of the sheet allow fasteners to be positioned centrally below the longitudinal rib of the roofing sheet for greater wind uplift resistance and allows direct engagement between the retaining tabs and the leading edge rib. Furthermore, the short trailing edge portion allows greater material efficiency in the roofing sheet compared to the prior art.

The alignment of the tabs 30 across the rib profile results in the fold line 37 between the tabs and the base 29 of the retaining member being parallel to the clip length, rather than perpendicular as in the prior art. Furthermore, the angled flanges 32 of the retaining formation are closely received in the top portion of the rib, restraining against bending of the clip in both the parallel or perpendicular directions.

Consequently, the wind uplift forces acting through the flanges 32 act substantially parallel to the plane 25 of the tab. Extreme uplift forces attempt to twist the tab. This mechanism results in considerably greater resistance to wind uplift forces than the prior art hump-shaped retaining formations, in which the uplift forces attempt to unfold the hump by bending along the existing perpendicular fold lines.

As the tabs substantially correspond to the rib profile, separate bird proofing accessories are not required.

C Unlike prior art clips, the tail 38 of the clip extends past the final retaini.g formation 25c, thus -7supporting the full sheet profile and compressing the insulation blanket in the region of connection of the laid sheet with the next clip. This arrangement also allows the head of the next clip to nest wit] ir, the channel section 24 at the tail of the previous clip, and the alignment of circular fastener holes 36 ensures exact positioning of the clips for correct roof pitching.

While particular embodiments of this invention have been described, it will be evident to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments and examples are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

e oo In the appended claims, the invention is defined with reference to the orientation for use in roof cladding, 25 where the plane of the sheets is generally horizontal.

This however should not be construed as limiting the invention to that orientation. The present invention o can, for example, be used for wall cladding.

Claims (12)

1. A cladding sheet and clip arrangement, the cladding sheet having spaced apart leading and trading edge regions and being arranged to be juxtaposed with a like cladding sheet with the leading edge region of one sheet overlapping the trailing edge region of the other sheet to form a longitudinal extending rib at said overlapping edge region, said leading edge region including a rib part and said trailing edge region including an upwardly facing shoulder and a distal edge having a downwardly turned lip, the clip arrangement including an elongate retaining clip having an endmost retaining formation including a pair of downwardly facing surfaces, said clip being adapted for partial insertion under said trailing edge of said sheet such that an endmost one of said downwardly facing surfaces locates in a retained position above the upwardly facing shoulder of said trailing edge region, wherein said endmost retaining formation includes i means for engaging said lip so as to retain said trailing edge region in said retained position and whe-n when in said retained position, the other downwardly facing surface of the endmost retaining formation is free for engagement with the leading edge rib part of a like cladding sheet so as to enable 20 the overlapping edge regions to be secured to an underlying structure by said clip arrangement.

2. A cladding sheet and clip arrangement according to claim 1, wherein said leading edge rib part includes a pair of opposed re-entrant portions, and wherein 25 when said rib part overlaps with the trail end region of a like sheet in said retained position, one of said re-entrant portions locates under said shoulder of the trailing edge region of the like sheet, and the other re-entrant portion is adapted to locate below said free downwardly facing surface of said endmost retaining formation.

3. A cladding sheet and clip arrangement according to claim 2, wherein the leading edge rib part is adapted to overlap in a snap fit engagement with the endmost retaining fDrmation and said trailing end region of the like sheet in said retained position. SWTNWOR3%SlIMNE ZNV 489? O7 3 s~ L3 -0-

4. A cladding sheet and clip arrangement accordin3 to claim 2 or 3, wherein the downwardly facing shoulder of the trailing edge region substantially conforms in profile to said endmost re-entrant portion.

5. A cladding sheet and clip arrangement according to any preceding claim, wherein said lip engaging means of the endmost retaining formation includes a flange behind which the lip of the trailing edge region of the cladding sheet is adapted to be retained.

6. A cladding sheet and clip arrangement according to claim 5, wherein the flange hooks under the lip of the trailing edge in locating the trailing edge region of the cladding sheet in said retaining position.

7. A cladding sheet according to any preceding claim, wherein said endrnost retaining formation is adapted to be secured t.3 an underlying structure when said trailing edge regions is in said retained position.

8. A cladding sheet in clip arrangement according to claim 7, wherein when in said overlapping arrangement with a like cladding sheet, said trailing edge region 20 does not extend beyond a longitudinal axis of the rib formed at said overlapping edge regions.

9. A cladding sheet and clip arrangement according to claim 8, wherein the clip arrangement is adapted to be secured to the underlying structure by fastening 25 means, and wherein when the cladding sheet is in engagement with the endmost formation in said retained position and is in overlapping arrangement with a like cladding sheet, said fastening means extends through said end most formation and is located substantially in !ine with the longitudinal axis of said rib formed at said overlapping edge region. 'WINWORD'SIM ONSYVNEV.89&7 OOC A cladding sheet and clip arrangement according to claim 1 wherein said clip has one or more further retaining formations spaced along the clip, and wherein said clip is adapted for hooking under the trailing edge region and fastening to an underlying structure so as to secure said trailing edge region in said retaining position. followed by snap-fitting of said like sheet over the clip so that the leading edge rib of said like sheet snap-fits over both the trailing edge region and the endmost retaining formation, and one or more intermediate ribs of the like sheet snap-fit over respective ones of said further retaining formations.

11. A method of fixing a plurality of cladding sheets to an underlying structure, the cladding sheets having at least one longitudinal extending rib and including b longitudinal extending leading and trailing edge, the leading edge being in the form of a rib part, the or each rib and rib part including an interior space bounded by opposing interior walls and the cladding sheets being fixed to the underlying structure by a clip incorporating a plurality of retaining formations locatable within the interior space of the respective ribs and rib part, the method including the steps of: a) fixing a first cladding sheet to the underlying structure, the cladding sheeting being fixed by a first retaining formation which is fastened to said 20 underlying F-ructure and which is in engagement with interior walls of a rib aF said crst cladding sheet; b) interconnecting a second retaining formation to the trailing edge of the first cladding sheet, the trailing edge o f said first cladding sheet including a hooked edge and wherein said trailing sheet is interconncsted with the second retaining 25 formation by the hooked edge being located in a recess in an upper surface of said second retaining formation; c) fastening said second retaining formation having said trailing edge connected thereto to the underlying structure; and d) fixing a second cladding sheet to the underlying structure by locating the leading edge of the second cladding sheet over said second retaining formation and said trailing edge of said first sheet and bringing the interior walls of said rib CC C~IWRIIOE~S3E1da CCC -11- part into engagement with said second retaining formation and said trailing edge of said first sheet.

12. A method of fixing a plurality of cladding sheets according to claim 11, wherein on bringing the interior walls of said rib part into engagement with said second retaining formation and said trailing edge of said first sheet, the second cladding sheet is caused to overlap the first cladding sheet to form a longitudinal rib at said overlapping region.

13. A method of fixing a plurality of cladding sheets according to either claim 11 or 12, wherein the interior walls of the rib and the rib part include opposed re- entrant portions which form a pair of upwardly facing shoulders, and wherein each retaining formation includes a pair of downwardly facing shoulders which are arranged to engage respective one of the upwardly facing shoulders. 0 -Dated this 29th day of August, 1997 20 PHILLIPS ORMONDE FITZPATRICK Patent Attorneys for the Applicant STRAMIT CORPORATION LIMITED I *s 0. 0 N n L-l-l ABSTRACT A cladding sheet (28) and clip (10) arrangement is disclosed. The sheet has a leading edge rib (26) and a trailing edge portion (33) which includes an upwardly facing shoulder The clip has an endmost retaining formation (25a) with a pair of downwardly facing surfaces the clip being partly inserted under the trailing edge of a previously laid sheet to locate an endmost one of the downwardly facing surfaces above the shoulder, with the other downwardly facing surface being free for engagement with the leading edge of the next sheet. The leading edge may have a pair of opposed re-entrant portions (40) which snap-fit engage with the shoulder and the free downwardly facing surface respectively. Recommended Figure: Fig. 8. e e i, dl