Non-Rotating Panel Clip

Abstract

A panel clip (1) for fixing a preformed concrete panel (10) to structural steelwork (12), includes a linear elongate body (2) terminating in a downward deflecting lip (3), the body including an aperture (4) formed in the linear body for receiving a fastening device (5) in which the clip includes a projecting tooth (6) protruding in the downward direction for engaging the preformed concrete panel and preventing the clip from rotating during tightening of the fastening device.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from Australian Provisional Patent Application No 2006907282 filed on 22 Dec. 2006, the content of which is incorporated herein by reference.

INTRODUCTION TO THE INVENTION

This invention relates to the method of building construction using prefabricated and tilt-up concrete panels and in particular to an improved method and fitting for attaching and fixing such concrete panels to structural steelwork.

BACKGROUND TO THE INVENTION

Pre-cast concrete panels in the form of tilt-up panels and other forms of pre-cast constructional members are enjoying an ever increasing penetration into the building and construction industry due to their versatility, reliability and structural strength. In addition, the very rapid and economical methodologies available for erecting such pre-cast concrete panels allow the very rapid and reliable erection of substantial constructions.

Typically, pre-cast concrete panels, including tilt-up panels are fastened to structural steel work, which is formed so as to provide a framework and supporting structure for a building in question. The pre-cast concrete panels effectively function as in-fill or walls, floors etc., and the attachment of the pre-cast concrete panels to the structural steelwork is the subject of the current patent application.

In the past, fastening and fixing of pre-cast concrete panels to structural steel work is accomplished by first welding a small clip or tab to the structural steelwork on a number of positions so as to provide a series of projecting tabs which can be used as a means of bolting or fastening concrete panels onto the structural steelwork without the need to drill or provide holes in the structural steelwork which would otherwise compromise the integral strength of the structural steelwork and generally necessitate the incursion of locking bolts very close to the edge of the pre-cast concrete panels. The use of welded tabs or clips to the structural steelwork allows the provision of a bolt to be inserted and attached to the concrete panel at a distance from the edge thereof and this provides a means for attaching the concrete panels to the structural steelwork.

Whilst it might be conceivable to use panel clips in the currently adopted methodologies without welding the clip to the structural steelwork, the practicalities of construction and erection are faced with a variety of problems including the uncontrolled rotation of the clip once it is drawn into abutment with the concrete panel so as to sandwich the structural steelwork between the clip and the panel. In addition, the logistical problems of assembly with workers having to man-handle and orientate the clips often in elevated and precarious positions, has seen the current methodologies adopted where the panel clips are welded onto the structural steelwork after erection thereof as a separate step after the pre-cast panels are drawn up into engagement with the structural steelwork and bolts are secured through the tabs into the concrete panels to effect the attachment of fixing of the concrete panels to the structural steelwork.

The above described methodologies involve the separate step of an operator welding the panel clips to the structural steelwork.

It would be desirable to provide an improved method and fittings which would overcome the previously described difficulties and limitations with the currently used panel clips.

STATEMENTS OF THE INVENTION

In one aspect the invention provides a panel clip for fixing a preformed concrete panel to structural steelwork said clip comprising a linear elongate body terminating in a downward deflecting lip, said body including an aperture formed in said linear body for receiving a fastening device wherein said clip includes a projecting tooth protruding in said downward direction for engaging said preformed concrete panel and preventing said clip from rotating during tightening of said fastening device.

The projecting tooth can be formed from any one of a number of preferred configurations including a projecting tooth formed on and protruding from the lip. Alternatively, the projecting tooth can be formed from the punch waste or stamping waste of the aperture with the stamping waste being cause to form around so as to project in a downward direction from the clip. In another embodiment the projecting tooth can be formed from a separate piece of punctual stamp waste formed from the lip itself.

An alternative embodiment of the projecting tooth is provided where the projecting tooth is formed as an elongate partial extension or tab extending from the underside of the clip body positioned so as to encompass the aperture.

Preferably the angle of deflection of the lip is about 5° or sufficient to accommodate the thickness of said structural steelwork and/or allow for compression of said clip during fixing of said concrete panel.

The aperture may be an elongate slot to accommodate slippage and movement during fixture.

The rebate formed in the concrete panel is preferably cruciform.

The clip is preferably formed of mild steel and hot dip galvanised.

In another aspect the invention provides a method of fixing pre-cast concrete panels and the like to steel structural work comprising fitting a panel clip as previously described to a pre-cast panel formed with a rebate wherein said clip is bolted or fastened to a ferrule in said panel and said clip is prevented from rotating during tightening by the co-operation of said tooth with said rebate.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described in more detail with reference to one particularly preferred embodiment as shown in FIGS. 1 through to 6:

FIG. 1 shows an under view of the clip.

FIG. 2 shows a rebate former.

FIG. 3 shows an exploded view of the clip fitting a panel to structural steel.

FIG. 4 shows a side view of the clip fixing a panel to structural steel.

FIG. 5 shows an alternative embodiment of the clip where the interlocking tab is produced by punching the aperture and bending a portion of the clip underneath so as form the tab.

FIG. 6 shows yet another embodiment with the interlocking tab being produced by slitting and then bending from a rear portion of the panel clip.

FIG. 7 shows yet another embodiment of the clip where the interlocking tab is welded onto the clip around the slotted hole to sit in a square recess formed in the panel.

LEGEND

• 1. Clip
• 2. Body
• 3. Lip
• 4. Aperture
• 5. Fastening device
• 6. Tooth
• 7. Cruciform arms
• 8. Central plug
• 9. Ferrule
• 10. Panel
• 11. Rebate
• 12. Structural steel

Referring to the figures, the invention provides an improved panel clip for fixing a concrete panel 10 to preformed structural steelwork 12, shown in FIGS. 3 and 4. The clip 1 comprises the relatively short and linear elongate body 2, terminating in a downwardly deflected short lip 3. The clip 1 provides a compact fastening device of similar proportions and materials to prior art clips. The body 2 includes an elongate slot as an aperture 4, which is formed in the straight or linear body part of the clip 2, toward the middle of the clip 1 and generally abutting the region of the body 2 which transforms into the downwardly deflecting lip 3. In a first embodiment the downwardly deflecting lip includes a short projecting tooth 6, protruding from the underside of the lip 3 in the downward direction adopted by the lip 3 relative to the body 2 of the clip 1. The angle of deflection of the lip 3 relative to the body is shown in the figures but would generally be expected to be in the order of about 5° or an angle selected to accommodate the thickness of the structural steel 12 as can be seen in FIG. 3.

Referring again to FIGS. 3 and 4 the panel clip of the invention is adapted to interact with a rebate 11, preformed in the panel 10 during casting and construction of the panel. During casting and construction of the panel, a rebate former as shown in FIG. 2 is used, so as to provide a cruciform rebate by virtue of the four cruciform arms 7 of the former in addition to a central plug 8. In this manner, the rebate former provides four options for engagement with the panel clip of the invention and thereby provides complete versatility during construction of the pre-cast panels which can then be fitted to structural steel using the clip of the invention in a variety of orientations.

In use, the panel clip of the invention allows pre-cast concrete panels incorporating the rebate to be raised and positioned in relation to the structural steel formations wherein the positioned panels can then be fitted and fixed to the structural steel by use of the panel clips of the invention where the user would fit a clip to the panel, such that the body of the clip would sandwich the structural steel member between the panel and the body per se., with the lip 3 and tooth 6 of the clip, being placed within the rebate 11 formed in the concrete panel. Once the clip is positioned, a fasting means 5 or bolt can then be passed through the elongate aperture or slot 4 and fitted to a threaded insert or ferrule 9, positioned within the panel 10. The bolt or fastener is then tightened, drawing the body of the clip down onto the structural steel member and tightly and snugly sandwiching the structural steel between the panel and the clip thereby securely fixing the panel to the structural steel. The inclined lip of the clip provides a measure of compliance and sprung tension to ensure the bolt does not loosen or come undone. As an additional security measure, the panel clip of the invention can be used in conjunction with the applicant's SEKURELOK™ washer as detailed in co-pending patent application PCT/AU2006/001371.

Referring now to FIGS. 5, 6 and 7, alternative configurations of the panel clip of the invention are shown where different methods of forming the tooth 6 are provided. Firstly referring to FIG. 5, the projecting tooth 6 is shown as being formed from the punch waste material projected from the clip body 2 during formation of the aperture 4. In this particular embodiment, a very economical method is provided for the formation of the projecting tooth without requirement for a separate provision and fitting of a tooth to the downward deflected short-lip 3. This particular embodiment of the invention provides for the bending and formation of the tooth into a position commensurate with the position of the tooth as shown and previously described with reference to FIG. 1.

Referring now to FIG. 6, an alternative method of forming the projecting tooth 6 is shown where this particular embodiment provides for the preparation and formation of the tooth as punch waste material resulting from the pressing of the lip from within the width of the downward deflected lip 3. Again, this method of forming the projecting lip does not require the separate step of forming and fixing the tooth to the downward deflecting lip and provides some economies in manufacture.

Referring now to FIG. 7, another embodiment providing an alternative method of forming the tooth 6 is shown, where the tooth in this particular embodiment takes the form of an elongate tab 6 extending from the underside of the body 1. The positioning of the elongate tab correlates with the position of the aperture 4 so as to encompass the aperture so as to ensure the adequate provision of an anti-rotational function of the clip relative to the position of the fastening device.

Among the advantages of the clip of the current invention, are its ability to be securely fixed to structural steel without the need to weld the clip onto the steel. The provision of the projecting tooth and its interaction with the rebate formed in the panel, ensures that the clip does not rotate or move outside its specified fitting configuration. The elongate slot and cruciform preparation of the rebate ensures that the panel clip is readily fitted and does not provide an impediment or require unnecessary alignment with a threaded insert or ferrule 9 positioned to be in the panel 10. In this manner, the clip of the invention is easy, efficient and safe to use in the sometimes exposed environments required for constructions of this type.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

1. A panel clip for fixing a preformed concrete panel to structural steelwork, said clip comprising a linear elongate body terminating in a downward deflecting lip, said body including an aperture formed in said linear body for receiving a fastening device wherein said clip includes a non load bearing projecting tooth protruding in a downward direction corresponding to said deflecting lip and formed intermediate of an end of said lip and said aperture for engaging an oversized rebate in said preformed concrete panel and preventing said clip from rotating during tightening of said fastening device whilst allowing lateral positioning of said clip during tightening.

2. A clip according to claim 1, wherein said projecting tooth protrudes from said lip.

3. A clip according to claim 1, wherein said projecting tooth is formed from a punch waste of said aperture.

4. A clip according to claim 1, wherein said projecting tooth is formed from a punch waste of an aperture formed in said lip.

5. A clip according to claim 1, wherein said projecting tooth is formed as an elongate tab extending from an underside of said body encompassing said aperture.

6. A clip according to claim 1, wherein said deflected lip is deflected at an angle sufficient to accommodate the thickness of said structural steelwork.

7. A clip according to claim 1, wherein said aperture is an elongate slot.

8. A clip according to claim 1, wherein said clip is formed of mild steel and is hot dip galvanized.

9. A method of fixing a precast concrete panel to structural steel work, comprising the steps of:

providing a panel clip of a type including a linear elongate body terminating in a downward deflecting lip, said body including an aperture formed in said linear body for receiving a fastening device wherein said clip includes a projecting tooth protruding in said downward direction for engaging said preformed concrete panel and preventing said clip from rotating during tightening of said fastening device,

fitting said panel clip to said precast concrete panel,

forming said precast concrete panel with a rebate for receiving said clip tooth, and

fastening said clip to said panel in a manner that said clip is prevented from rotating during tightening by cooperation of said tooth with said rebate.

10. (canceled)

11. (canceled)

12. A clip A clip according to claim 6, wherein said angle is about 5°.