Related Application

This application claims priority from Australian Patent Application No. 2010904783, the contents of which are incorporated by reference.

Field of the Invention

The invention relates to a spacer or chair for supporting reinforcing bar such as used to reinforce concrete.

Background of the Invention

Reinforced concrete slab construction can use one or more layers of reinforcing material, such as a mesh formed of steel bars. The mesh layers are spaced apart in tiers and may be referred to as decks.

A first one of the decks is supported above a surface on which the slab is to be poured by a series of lower deck supports, which are generally located at places of intersection in the mesh, where the bars of the mesh cross.

In a two tier arrangement, the top deck is supported on relatively tall chairs which are generally positioned at spaced apart locations, away from the places of intersection of the lower deck, where the lower deck supports are 'located. The chairs have legs which are widely spaced to avoid contact with the lower deck whilst being long enough to rest directly on the underlying surface. Object of the Invention

†he present invention seeks to provide an alternative form of chair.

Summary of the Invention

In accordance with the invention, there is provided a reinforced concrete spacer for supporting a bar of a reinforcing top deck, including:

an upper body with a coupling for supporting the top deck; and

a main body with a connector to engage a bar of a bottom deck, so that the spacer serves to locate and space the top deck relative to the bottom deck.

Preferably, the connector is in the form of a recess in the main body, which has an entry toward a base of the spacer. ¹

Preferably, the entry is at least partially closed by a resilient clip to capture the bar in the recess.

Preferably, the recess tapers toward the upper section, so that the connector is adapted to fit with bars of different thickness.

Preferably, the connector has a saddle portion which rests directly on the bar to support the spacer. Preferably, the spacer includes a pair of aligned connectors to engage the bar.

Preferably, the spacer includes a second pair of connectors to receive a cross bar.

Preferably, the base has rim sections connected to the main body, the rim sections extending between each connector. Preferably, each rim section has a tab which projects into the entry of the associated recess to define the resilient clip. Preferably, the spacer is generally in the shape of a hollow cone suitable for stacking purposes. In another aspect, there is provided a method of supporting reinforcing mesh of an upper deck over reinforcing mesh of a lower deck, including fitting spacers, formed in accordance with the above described spacer, onto intersecting cross bars of the reinforcing mesh of the lower deck and connecting cross bars of the upper deck with associated couplings of the spacers, in order to support the upper deck above the lower deck.

Preferably the method further includes arranging a first set of spacers, also formed in accordance with the spacer described above, on a support surface and connecting the cross bars of the lower deck to associated couplings of the first set of spacers, in order to support the lower deck above the support surface.

Detailed Description of the Drawings

The invention is described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of the a spacer in accordance with the invention;

Figure 2 is side view of the spacer; Figure 3 is a top view of the spacer;

Figure 4 is a cross-sectional view of the spacer, taken along the line A-A shown in Figure 3; Figure 5 is a perspective view of another spacer. Detailed Description of the Invention

A spacer 1 is shown in Figure 1 as including an upper body 2, a main body 3 and base 4. The upper body 2 is provided with a series of couplings 5 in the form of notches 6 which receive cross bars 7, 8 of a reinforcing mesh 9 of an upper deck 10. The notches 6 lie between wall sections 1 1 that taper upwardly into lateral fingers 12 that project inwardly to form a resilient clip 13, to releasably lock the bars into the respective couplings 5. The main body 3 is hollow and generally conical shaped. The main body 3 includes four legs 14 that extend down from the upper body 2. The legs 14 terminate in connectors 15 which receive cross bars 16, 17 of a reinforcing mesh 18 of a lower deck 20.

Each connector 15 is in the form of a recess 21 which opens toward the base 22. The walls 23 defining the recess 21 are tapered in a direction toward the upper body 2 so that the connector 15 is adapted to fit with bars 16, 17 of different thickness.

A saddle portion 24 is provided at the top 25 of each recess 21. The saddle portion 24 rests directly on the bar 16 to support the spacer 1. A rib 26 extends along the outside 27 of each leg 14 to provide reinforcement to the saddle portion 24.

The base 22 is provided as a series of rim sections 28 which extend between the legs 14, The rim sections 28 are interrupted at the connectors 15. Each rim section 28 has a tab 29 which projects into an entry 30 of the associated recess 21 to define a resilient clip 31 , which at least partially closes the entry 30 and serves to capture the bar 17 in the connector 15.

The connectors 15 are arranged in aligned pairs, at diametrically opposed locations about the base 22. Since one of the bars 17 is above the other bar 16, the spacer 1 will only be supported on one pair of saddle portions 24 at any one time. However, the saddle portions 24 are spaced apart to provide stability to the spacer 1 in a direction along the bar 17. Limited rotational movement about the bar 17 may occur until the bar 7 of the upper deck 10 is located in place, which locks the spacer 1 relative to both the upper and lower decks 10, 20. Turning to Figure 2, the bar 17 is shown hard up against the saddle portion 24, while the upper body 2 is securely located relative to the upper deck 10 by the bar 7 being locked into a bottom 32 of the notch 6.

In order for the spacer 1 to be secured in place, the couplings 5 of the upper body 2 are directly in line with the connectors 15 of the main body 3. This ensures not only solid and non-rotatable connection between the decks 10, 20 and the spacer 1 but also means the intersection of the top deck 10 is aligned with the bottom deck 20.

With reference to Figure 3, the alignment of the mesh layers of the top and bottom deck 10, 20 is evident from the plan view, where the spacer 1 is directly over the intersection of the bars of the lower deck 20 such that the bars of the lower deck 20 cannot be seen. Such alignment allows for, uniform and reliable positioning of not only the mesh layers but also the spacer 1 itself, as compared to the potentially random positioning of the prior art support chairs.

In relation to Figure 4, the alignment is again apparent. In this Figure, however, it is clear the spacer 1 is resting directly on the bar 17 via the saddle portions 24. The spacer is not resting on the bottom spacer 33 at all. This ensures there is no overlap between the spacers 1 and 33, which maximises the open spaces or voids between the spacers 1 and 33 and aligns the gaps between the legs of each spacer for maximum flow through of concrete when poured in and around the spacer 1. This in turn ensures as much of the bars 16 and 17 as possible are encapsulated in the concrete.

In Figures 1 to 4, the bottom spacer 33 is shown as being of a lesser height than the spacer 1. The height of both spacers 1 , 33 is determined by the required nominal or industry standard heights for the top and bottom decks and the spacers 1 , 33 can be cast as either longer or shorter to suit, as required. In one possible arrangement the height of the deck 10 above the desk 20 could be the same as the height of the deck 20 above the supporting surface, in which case the spacers 1 , 33 can be the same height such that identical spacers could be used to support not only the top deck 10 but the bottom deck 20 as well. If additional height is needed between the top deck 10 and the bottom deck 20, an additional intermediate spacer could simply be stacked in the middle to effectively raise the level of the top most spacer.

In any event, the method of supporting the upper deck 10 above the lower deck 20 is straight forward, particularly when the spacer 33 is identical to the spacer 1. A first set of spacers I or 33 is firstly arranged on a support surface and the lower deck 20 is lowered onto the spacers 1 , 33 so that the coupling 5 of each spacer 1 , 33 connects with associated cross bars of the lower deck 20, in order to support the lower deck 20 above the support surface. The method then involves fitting a second set of spacers 1 on top of the intersecting cross bars of the lower deck 20 and connecting cross bars of the upper deck with associated couplings 5 of the spacers 1 , in order to support the upper deck 10 above the lower deck 20. Concrete is then poured over both supported decks 10, 20 and through and around the spacers 1 , 33 to form a reinforced concrete slab. It should be appreciated the conical shape of the spacer provides a considerably simpler and more cost effective way of supporting reinforcing mesh for a concrete slab, as compared to the conventional system requiring supports and bar chairs of different dimensions. The chairs 1 , 33 can either be used in a single layer application, where only one deck 20 of reinforcing material is supported, or stacked on another chair for use in twin layer applications, as described above, to support a second deck 10 of reinforcing material. The chairs 1 , 33 are preferably formed of moulded plastics material so they are cheap and convenient substitutes for conventional chairs because of the double use application option. The conical shape also facilitates multiple spacers being conveniently stacked for either storage or transportation. Referring now to Figure 5, an alternative form of spacer 40 is shown, where like parts are denoted with like reference numerals.

Similarly to the spacer of Figures 1 to 4, the spacer 40 has an upper body 2 with couplings 5 and a main body 3 with connectors 15. Each connector 15 is formed by a recess 21 which opens toward a base 22 of the spacer 40. The recess 21 is shaped with an enlarged section that tapers in a direction toward the upper body 2 so as to accommodate and snugly fit with different width bars. The entry 30 to each recess 21 is defined between opposed projections 34 which form a clip 31 to capture the bar 17 in the connector 15. Each projection 34 extends from an outwardly flared foot 35 which defines a rim section 28 of the base 22.

The spacer 40 may be integrally moulded or formed in two parts 36, 37, which can be snap fit together via clips 38, when needed.

Although the appearance of the spacer 40 is quite different to the spacer 1 , the functionality is the same in so far as the spacer 40 can stably locate the top deck 10 relative to the bottom deck 20 at an intersection of the bars 7, 8 and 16, 17 and there is no need to support the top deck 10 by tall chairs seated directly on the underlying surface.

The ability to the top deck 10 to be supported directly from the deck 20 below may result in less plastics material being used overall as the prior art top deck chairs are relatively bulky and large as they have to reach the entire distance from the top deck down to the underlying surface.

Also, stacking the spacer 1 directly on top of a bottom spacer 33 reduces the plastics "foot print" in the slab, which may be advantageous in so far as improving the overall percentage of concrete relative to plastic at least on the bottom surface of the resultant slab. The invention has been described by way of non-limiting example only and many modifications and variations may be made thereto without departing from the spirit and scope of the invention described.

ist of Parts

1. Spacer . Upper body

3. Main body . Base

5. Coupling . Notches

7. Cross bar . Cross bar . Mesh

10. Upper deck

1 1. Wall sections

*2· Fingers

13. Clip

14. Leg

15. Connector

16. Cross bar

17. Cross bar

18. Mesh

19.

0. Lower deck 1. Recess 2. Base

23. Walls

24. Saddle portion

25. Top

26. Rib

27. Outside

28. Rim Section

29. Tab 30. Entr

31. Clip

32. Bottom

33. Bottom spacer

34. Projections

35. Foot

36. Part

37. Part

38. Clip

39.

40. Spacer