AU2008201259A1

AU2008201259A1 - Ferrule supports

Info

Publication number: AU2008201259A1
Application number: AU2008201259A
Authority: AU
Inventors: Martin Randall
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-03-25
Filing date: 2008-03-18
Publication date: 2008-10-09

Description

OO

C FERRULE SUPPORTS This invention relates to ferrule supports. The invention has particular application to ferrule supports for supporting 00 fixing ferrules of the type used in the construction of Ch concrete tilt-slab panels and the invention will be described with particular reference to such use. However, it is to be 0 S understood that the invention may have application to 00 supporting ferrules and the like in concrete slabs generally and perhaps in slabs and panels formed of settable materials other than concrete.

Commonly, fixing ferrules are circular or hexagonal in cross section and have a threaded axial bore opening at one end (the proximal end) and terminating in a blind end towards Sthe other end (the distal end) with a lateral (or cross) bore extending from one side to the other in the portion between the blind end and the distal end. However, fixing ferrules need not have all those particular features and could be made in other configurations if desired.

Typically, fixing ferrules are set in various locations in tilt-slab panels for the purpose of connecting braces, plates, brackets or the like thereto. The locations selected depend on the particular purpose of the ferrule. Typically, some ferrules are located such that the threaded bore opens to one side of the panel while some may have it opening to the 00 -2-

C

S other side. Some may open to the top or bottom edges of the t panel and some may open to the side edges.

Various types of supports are used to locate ferrules in

OO

the moulds in which tilt-slab panels are manufactured Ch 5 depending on the desired location. One type of support used to S locate ferrules opening to the underside face of the panel

C

00 (while the panel is being formed in a horizontal mould) has a

O

disc-like base and an upstanding cylindrical plug adapted to tightly slide into the threaded bore of the ferrule being supported. Other similar supports have a threaded plug adapted to screw into the threaded bore of the ferrule. In use of such supports, the disc-like base is nailed to the pad, slab or formwork on or against which the concrete is to be poured and a ferrule is pushed or screwed onto the plug portion as the case may be, thus securing the ferrule in place. Such supports are commonly formed from polyethylene or similar plastics material and are removed once the tilt slab has set. One problem with such ferrule supports is that the plug does not resist side loads applied to the ferrule sufficiently, be it threaded or slide on, and as a result, persons fitting steel reinforcing bar in the mould or pouring concrete in the mould can disrupt the ferrule and cause it to lean one way or another instead of standing perpendicular to the surface to which the support is fixed, with the result that when the concrete sets, the ferrule is unable to accept a bolt due to OO -3- 0 S its inclination, and worse still cannot be drilled out. In t such situations, the plate, bracket or fixture that was intended to be bolted to the ferrule must be re-drilled and a 0O chemically set bolt or a mechanical expansion bolt such as a CN 5 dyna-bolt must be fitted to the tilt-slab in a different S location.

0 OO The present invention is aimed at ameliorating one or 00 more of the aforementioned problems by providing a ferrule support which is less susceptible to accidental damage or movement prior to and during pouring of concrete in the mould.

With the foregoing in view, the invention resides broadly in a ferrule support including: a plug adapted to engage in the bore of a fixing ferrule to releasably secure the fixing ferrule thereto; and a retainer adapted to engage said plug for securing said plug to formwork and support means integral with or operatively connected to said retainer adapted to engage the side face of the fixing ferrule with which the plug is intended to be engaged for supporting the ferrule in a desired upright attitude relative to the plug.

Preferably, said plug has a bore engagement portion which is adapted to engage in the bore of the fixing ferrule and a former engagement portion which is adapted to engage with the surface of a former when the bore engagement portion is engaged in the bore of the fixing ferrule. In a preferred form -4oc

C

D

the former engagement portion is a disc like portion from which the bore engagement portion extends.

Preferably, said retainer has securement means for securing it to the former and preferably said support means is operatively connected to the securement means.

In another aspect, the invention resides broadly in a D ferrule support including: D a plug having a bore engagement portion which is adapted to engage in the bore of a fixing ferrule and a formwork 3 engagement portion which is adapted to engage with the surface of formwork; and a retainer adapted to engage with said formwork engagement portion to retain said plug in a predetermined position relative to said retainer, said retainer including securement means by which it may be secured to formwork and one or more support means operatively connected to said securement means and defining at least two opposed contact points spaced from said formwork engagement portion.

Preferably, the support means is adapted to engage the formwork remote from the fixing ferrule being supported thereby providing a greater reaction moment for resisting bending. In a preferred form said support means comprises a plurality of thin spaced apart webs extending radially from the ferrule being supported.

00 00 O In order that the invention may be more easily understood and put into practical effect, reference will now be made to the accompanying drawings wherein: 00 Fig. 1 is a pictorial representation of a ferrule support according to the invention ready for use; Fig. 2 is a pictorial representation of the ferrule 00 support of Fig. 1 as moulded with two optional plugs connected O to the retainer; Fig. 3 is a pictorial representation of the ferrule support of Fig. 1 with the two optional plugs removed from the retainer shown in Fig. 2; Fig. 4 is a pictorial representation of the ferrule support of Fig. 1 supporting a ferrule; Fig. 5 is pictorial representation of a ferrule connected to an alternative plug which can be used with the retainer of the ferrule support of Fig. 1 instead of the plug shown in Figs. 1 to 4; Fig. 6 is a pictorial representation of the retainer of the ferrule support of Fig. 1 from one side; Fig. 7 is a plan view of the bottom face of the retainer of the ferrule support of Fig. 1; and Fig. 8 is a bottom plan view of the plug of the ferrule support of Fig. 1 from the under side (and also the optional plug shown in Figs. 2 and 3 and also the alternative plug shown in Fig. 00 -6- 00 O The ferrule support 10 illustrated in Fig. 1 includes a plug 11 and retainer 12 all moulded from polyethylene although other suitable plastics materials could be used if desired.

00 The plug has a bore engagement portion 13 which is sized to 5 slidably engage in the threaded axial bore of a ferrule 14 as In a tight push fit. The plug also has a formwork engagement 00 portion 16 of generally disc-like form with a bottom face 17 adapted to rest on or against the face of a sheet of ply or metal formwork or a pad, slab or the like on which a concrete tilt slab is to be constructed. Advantageously, the formwork engagement portion has a slot 18 formed therein which is adapted to receive a large screw driver or the like to assist with removal from the ferrule at the desired time as will be described in more detail later. As can be seen in Fig. 5, the form work engagement portion has a tapered peripheral edge 19.

The retainer 12 has a generally cylindrical base portion 21 from which two opposed fixing lugs 22 and 23 extend, each lug having a hole 24 therein through which a nail can be driven to secure the retainer to formwork or a pad or slab as the case may be. Four angularly spaced support webs 26 to 29 extend from the cylindrical base and are arranged in opposed pairs such that adjacent webs define an angle of therebetween and each web extends radially away from the axis of the cylindrical base portion. Each web has an inner edge 31 which defines a contact line for contacting the cylindrical 00 O face of the ferrule 14 as can be seen in Fig. 4 thereby t securing the ferrule to the retainer and providing support to 00 the ferrule against side ways movement relative to the cylindrical base portion and the securing lugs 22 and 23. In 5 this embodiment a flexible fin 38 extends radially inwards from the inner edge of each web and is adapted to help 00 accommodate slight variations in ferrule diameter by bending sideways in the case of an oversized ferrule and remaining fully extended in the case of an undersized ferrule.

Advantageously, each web has a bottom edge 32 which is adapted to engage the formwork or pad to which the retainer is to be secured thereby providing further support for the retainer against tilting or bending. As can be seen in the drawings, the height of the cylindrical base portion is lower in the opposed sections adjacent the securing lugs and higher in the sections remote from the securing lugs thereby providing the opportunity for using the ferrule support as a bar chair with different heights of bar support. As can be seen more clearly in Fig. 7, the retainer has a recess adjacent its bottom face which is adapted to receive therein the formwork engagement portion of the plug 11. Advantageously, the recess is defined at its periphery by a tapered peripheral edge 36 which is adapted to engage with the corresponding tapered edge 19 of the formwork engagement portion 19 of the plug so as to 00 -8- O provide a reasonably tight fit of the formwork engagement portion in the retainer.

00 In use, the plugs 11 and lla are removed from the retainer immediately prior to use and the correct size ferrule 5 plug to suit the selected ferrule is retained and fitted to In the recess 34 of the retainer while the other plug is 00 discarded as can be seen in Fig. 1. The retainer with the plug fitted thereto is then fixed to the formwork, underlying pad or the like as the case may be by driving two nails or screws through the holes 24 into the underlying formwork whereupon the underface 17 of the formwork engagement portion will rest on the formwork or the pad and the bottom edges 32 of the webs will also rest thereon providing good support, the retainer retaining the plug in the recess and securing it to the iformwork. The selected ferrule is then pushed between the inner edges 31 of the webs and onto the bore engagement portion 13 of the plug. In the case of a threaded plug being used, the ferrule is simply screwed onto the bore engagement portion of the plug. A piece of reinforcing bar is then placed in the cross bore 15 of the ferrule and fixed to other reinforcing bar in the slab to be built in known manner.

Advantageously, the webs support the ferrule against lateral movement thus decreasing the likelihood of the ferrule tilting under the load of the steel bars being laid in the formwork or workmen walking on the reinforcing bars therein. In other -9- 00 O0 words, the ferrule support assists in keeping the longitudinal axis of the ferrule perpendicular to the face of the slab to which it opens as desired. Once the slab has been erected, the 00 plug 11 can be removed from the ferrule to expose the threaded S5 bore and whatever is required to be bolted to the ferrule can In then be secured. In the case of a threaded plug 11, the slot 00 18 provides for removal by a screw driver or the like.

0O SThe foregoing description has been given by way of illustrative example of the invention and many modifications in variations which will be apparent to persons skilled in the art may be made without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. With the foregoing in view, the invention resides broadly 00 in a ferrule support including: 5 a plug adapted to engage in the bore of a fixing ferrule In to releasably secure the fixing ferrule thereto; and 00 a retainer adapted to engage said plug for securing said 00 S plug to formwork and support means integral with or operatively connected to said retainer adapted to engage the side face of the fixing ferrule with which the plug is intended to be engaged for supporting the ferrule in a desired upright attitude relative to the plug.

2. A ferrule support including: a plug having a bore engagement portion which is adapted to engage in the bore of a fixing ferrule and a formwork engagement portion which is adapted to engage with the surface of formwork; and a retainer adapted to engage with said formwork engagement portion to retain said plug in a predetermined position relative to said retainer, said retainer including securement means by which it may be secured to formwork and one or more support means operatively connected to said securement means and defining at least two opposed contact points spaced from said formwork engagement portion.