GB2088434A - Resilient Deformable Reinforcement-bar Spacer - Google Patents

Abstract

The bar spacer has a disc-like body including an outer rim 1, an inner enclosure 2, and spokes 3. The rim and the enclosure are correspondingly gapped to provide an entrance 4 which narrows to less than the diameter of the enclosure. The rim has weakening(s) or break(s) 7 in continuity whereby the disc-like shape is retained upon deformation of the enclosure to receive a reinforcing bar 8a of larger diameter than the undeformed enclosure. Preferably arm(s) 5 extend into the enclosure to grip bars of any diameter accommodated in the enclosure. <IMAGE>

Description

SPECIFICATION Reinforcement Bar Spacer This invention relates to spacer means for holding steel reinforcement bars in appropriate positions prior to the setting of reinforced concrete and the like.

Reinforcement bars for this purpose are commonly supplied and used in a variety of diameters, and the variation may be of the order of two or three times between the smallest and the largest.

It is convenient to use, for the purpose of holding the reinforcement temporarily inland of the edges and surfaces of the concrete prior to setting, a spacer which is generally disc-shaped and accommodates the bar approximately centrally. To save having to thread each spacer onto the end of the bar, it is convenient to have a radical entry for the bar to move into the central position.

Such spacers are conveniently made of synthetic resinous plastics material and, whilst they must be sufficiently strong to sustain the bar in position, they must not occupy an unduly large volume in the concrete.

A conventional prior art form of such spacer is illustrated in Figure 1 of the accompanying drawings. It has an outer rim "A", and inner ring "B", and spokes "C", and part of the rim and ring are omitted to leave a radial entrance "D" to permit the reinforcement bar "E" to enter the seat in the ring "B". In Figure 1, the spacer is accommodating a bar "D" which is of an appropriate size for the ring "B" and for the entrance "D". Referring to Figure 2 of the drawings, there is seen the same spacer when an attempt has been made to introduce a reinforcement barE' which is of about twice the radius of the bar "E". The entrance has become unduly widened, and the whole structure of the disc has become distorted so that there is no longer a likelihood of the bar El remaining properly supported in spaced condition.

It is accordingly the object of the present invention to provide an improved form of spacer which can accommodate reinforcement bars of relatively widely varying diameter, say a variation of the order of 2-3, without losing its generally disc-like formation.

According to the present invention, a reinforcement bar spacer comprises a generally disc-like resiliently-deformable body including an outer rim portion, an inner enclosure, and a plurality of spokes coupling the rim and the enclosure, the rim and the enclosure being correspondingly gapped to provide an entrance which narrows to less than the width of the enclosure, the rim being provided with at least one weakening or break in continuity whereby the generally disc-like shape of the spacer is retained upon deformation of the enclosure to receive a reinforcement bar of larger diameter than the undeformed enclosure.

There may be provided an arm, or a pair of arms, extending from the rim or from the enclosure itself into the area enclosed by the enclosure, whereby a bar introduced into the enclosure is always held between the arms and is thus generally centred in the enclosure. Such arm or arms may have a serrated surface contacted by the bar, for better retention of the bar in the enclosure.

In a preferred form, the rim has two gaps disposed at approximately diametral positions, and the entrance is at about 90 to the line of the two gaps.

The rim may have radial projections to enhance its grip on the concrete, and/or to prevent the spacer from rolling freely.

The spacer may be of the same axial dimension across its diameter, or may have a generally axially thicker hub portion, e.g. the enclosure itself, and a generally axially thinner rim portion.

The break in continuity of the rim may be such that, prior to deformation, there is a circumferential gap between the adjacent portions of the rim. In an alternative, the break in continuity may be such that there is no gap between the adjacent portions, which overlap either radially, or axially of the spacer disc.

The adjacent portions of the rim, at the break in continuity, may have extensions in one or both axial directions.

The rim may be continuous circumferentially, other than at the entrance, but provided with one or more weakened points on its circumference, e.g. cut out portions radially inwardly, or radially outwardly, or both.

In order that the nature of the invention may be readily ascertained, some embodiments in accordance with the invention are hereinafter particularly described with reference to the figures of the accompanying drawings, wherein: Fig. 1 is an elevation of a prior art spacer accommodating a bar of the correct diameter; Fig. 2 is an elevation of the same prior art spacer which has become deformed permanently due to the forcing of an oversize bar into the spacer entrance; Fig. 3 is an elevation of an embodiment of the improved spacer of the present invention, seen accommodating a bar of small diameter; Fig. 4 is an elevation of the spacer of Fig. 3, seen accommodating a bar of about twice the diameter, and without serious deformation away from a disc-like shape; Figs. 5 and 6 are partial elevations to show alternative forms of outer rim;; Figs. 7 and 8 are edge elevations to show alternative shapes of the spacer; Fig. 9 shows various alternatives for the enclosure.

Figs. 1 and 2 have been described hereinabove, and need no further explanation.

Referring to Figs. 3 and 4, the improved spacer comprises a rim 1, an enclosure 2, a plurality of spokes 3, and an entrance 4 which narrows to less then the width of the enclosure. On the enclosure are two resilient arms 5 having teeth 6.

The rim is discontinuous, and includes two gaps 7. The spacer as a whole is generally disc-shaped.

When a bar 8 of small diameter, relative to the width of the enclosure, is introduced, the spacer is temporarily distorted, by bending at points "P" and "Q", to enable the entrance 4 to widen sufficiently for the bar 8 to pass through the narrowest point between the arms 5. The spacer then returns to its substantially unconstrained state, with the exception that the arms 5 remain bent and grip the bar 8 to hold it centrally in the enclosure.

In Fig. 4 there is shown the same spacer, but with a bar 8a of twice the diameter inserted in the enclosure. After insertion, the shaper remains slightly distorted, by bending at points "P" and "Q" such that the entrance 4b is somewhat wider, and the gap 7a are somewhat narrower. The arms 5 are pressed tightly against the enclosure, and the bar is gripped by the arms 5. Nevertheless, the shaper as a whole retains its disc-like shape.

Figs. 5 and 6 show modifications of the rim 1 to have radial projections 9, Fig. 5, or to have radial projections 10, Fig. 6.

Figs. 7 and 8 show respectively an edge view of a parallel-faced spacer, and an edge view of a spacer with an axially wider enclosure 2 and an axially narrower rim 1.

Fig. 9 shows various modifications of the enclosure 2 with and without an arm or arms 5, and an embodiment wherein the arms 5 are on the rim 1.

It will be appreciated that the invention is not restricted to the particular details described above with reference to the drawings but that numerous modifications and variations can be made without departing from the scope of the invention as defined in the following claims.

Claims (16)

Claims

1. A reinforcement bar spacer comprising a generally disc-like resiliently-deformable body including an outer rim, an inner enclosure, and a plurality of spokes coupling the rim and the enclosure, the rim and the enclosure being correspondingly gapped to provide an entrance which narrows to less than the diameter of the enclosure, the rim being provided with at least one weakening or break in continuity whereby the generally disc-like shape of the spacer is retained upon deformation of the enclosure to receive a reinforcement bar of larger diameter than the undeformed enclosure.

2. A spacer as claimed in Claim 1 wherein one or more arms extend into the enclosure to grip bars of any diameter accommodated in the enclosure.

3. A spacer as claimed in Claim 2 wherein said one or more arms have a serrated surface contacted by the bar accommodated in the enclosure.

4. A spacer as claimed in Claim 2 or Claim 3 wherein a pair of said arms extend into the enclosure from respective sides of the said entrance to the enclosure.

5. A spacer as claimed in any one of the preceding Claims wherein said break is constituted by one or more gaps between respective adjacent portions of the rim.

6. A spacer as claimed in CLaim 5 wherein there are two said gaps disposed at approximately diametrical positions with the line of the two gaps approximately perpendicular to the entrance.

7. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to and as shown in Figs. 3 and 4.

8. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to Fig. 5.

9. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to Fig. 6.

10. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference too Fig. 7.

11. A spacer as claimed in Claim 1 and substantially as herein before described with reference to Fig. 8.

12. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to the first embodiment shown in Fig. 9.

13. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to the second embodiment shown in Fig. 9.

14. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to the third embodiment shown in Fig.

9.

1 5. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to the fourth embodiment shown in Fig.

9.

16. A spacer as claimed in Claim 1 and substantially as hereinbefore described with reference to the fifth embodiment shown in Fig. 9