US3449882A - Reinforcing rod spacer - Google Patents

Description

June 17, 1969I i w @TT ET AL 3,449,882 j REINFoRcING Ron SPACER Filed April 24, 1967 sheet ,Z of 2 United States Patent O U.S. Cl. 52-689 4 Claims ABSTRACT OF THE DISCLOSURE A chair spacer for accommodating rods of differing diameters for use in moulds is described. The spacer is made of a resilient material and includes one portion which accepts rods of smaller diameter between a pair of finger members, and a second portion for retaining rods of larger diameter between the noses of a pair of linear arms.

This invention relates to a spacer or chair for the support and location of reinforcing rods for use particularly in moulded material. It has particular reference to the use in conjunction with reinforced concrete.

In the past the normal method of assembling reinforcing rods before the pouring of concrete into which the rods are to become embedded has been for the artisans concerned to lay out the rods in the position in which they will be required, and to wire the rods together to form an integrated structure in the space defined by the formwork for the concrete. This structure must be strong enough to withstand the weight of persons or other objects placed on it.

More recently metallic chairs or spacers have been used for supporting and standing off rods which must be spaced from the surfaces of the formwork so that when the concrete hardens the rods will have proper bonding and be protected from the weather. Such spacers receive their respective rods which are retained by bending of parts of the spacer. Other spacers are of a plastic in which the rod can sit, and within which it can be retained by wiring the rod onto the seat of the spacer. Still other spacers are of plastic which is distorted to embrace the rod for which it is designed.

While the plastic chair finds favour in the construction industry, those on the market are capable of cooperating effectively with only the one size of reinforcing rod for which they are respectively made and this leads to a problem in inventory since rods of different sizes are required on even quite simple jobs.

With the drawbacks of the prior art in mind the present invention has been developed and provides a concrete spacer chair of a resilient material which can space a rod from the edge of formwork, which retains the rod seated within the chair without the need for wiring and which is specifically adapted for accommodating and effectively securing rods of different sizes A description of the invention now follows and reference will be made to the accompanying drawings in which:

FIGURE 1 shows a side view of a spacer constructed in accordance with the teaching of the invention,

FIGURE 2 shows a plan view of the device of FIG- URE 1 from above,

FIGURE 3 shows a plan view of FIGURE 1 from below,

FIGURE 4 shows the position taken up by a rod of one size when employed with the spacer of the invention,

FIGURE 5 shows the position of a rod of a second size in the spacer.

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As seen with reference to FIGURE l the spacer chair comprises a base support part 1 and an upper rod encompassing part 2. The base 1 comprises a pair of wing leg supports 5 extending in a direction transverse to the plane of FIGURE 1 (see FIGURES 2 and 3) for a seat 6. Beneath the seat 6 additional support is formed by a web 7 which terminates in cross foot rail 8 in the same plane as the foot edge 9 of the wing legs S. The web 7 is reinforced by the raising of shoulders 10 adjacently above the cross foot rail 8.

The seat 6 is shaped to define a V shaped crotch portion 15 with a fiat bottom shelf 14 and which is bounded by two resilient linear arms 16 rising from and integral with the seat 6. The arms 16 each carry an inwardly extending nose 17. The arms also includes downwardly extending fingers 18 which project inwardly and are spaced from one another at a distance somewhat less than that between the tips 19 of the noses 17.

The spacer is moulded of a resilient plastic material for preference, and may consist of nylon, ABS, polypropylene or polyethylene for example. Other similar tough resilient plastics may be employed depending upon the cost and availability.

With reference now to FIGURE 4 the function of the spacer when accepting a small reinforcing rod 25 can be seen, The rod 25 is entered into the upper portion 2 by passing it through the space 26 between the tips 19 of the nose portions 17. The gap between the ends 27 of the fingers 18 is two small for the rod 25 to pass through freely, but the fingers are displaced downwards until they retract sufficiently to allow the rod to pass. The rod finally comes to rest on the fiat bottom shelf 14 in the lower part of the crotch portion 15 being held in position by the tips 27 of the fingers 18.

When the chair is to be used for accommodating a larger rod such as shown at 30, the rod can not pass through the space 26 but deflects the noses 17 out of position by forcing back the arms 16 from the broken lined to the full lined position (FIGURE 5). The fingers 18 which are much more flexible than the noses 17 and are bent downwards to allow the reinforcing rod 30 to be accommodated further up the crotch portion 15 against the fingers 18. The actual position occupied by the rod 30 will of course depend upon its diameter.

For accommodating a very much larger rod such as shown at 40 the spacer is supplied with fingers 18 removed during manufacturing. The rod deflects the noses 17 out of position and finds a final position in the V, dependent upon the size of the rod, 4but invariably resting on flat bottom 14.

The wing legs 5 are particularly valuable in giving strong broad feet to the structure so that there is little tendency to be canted or overturned when gripping a rod, and should the chair become displaced either longitudinally or axially of the rod.

The web 7 serves to tie the two wing legs 5 together so that they can not be splayed outwards (in the view of FIGURE 1) when carrying a heavy rod. The shoulders 10 help this strengthening and further prevent any buckling of the web under heavy load or side pressure.

By adopting the structure of the invention a wide range of sizes of reinforcing rods can be employed with a single size of spacer chair, which effectively will hold and locate the rods and without wiring them into position, and which is extremely strong and resistant to displacing.

We claim:

1. A chair spacer formed of a resilient material for accommodating rods from a range of differing diameters which comprises, a seat, a pair of triangular wing legs for said seat extending outwardly and downwardly from said seat, a web extending transversely between said legs and 3 beneath said seat, a pair of linear arms extending upwards and outwardly from said seat to define a crotch portion therebetween, a pair of inwardly directed nose members at the extremities of said arms, and a locating pair of defiectable inwardly directed finger members mounted on said arms and intermediate between said crotch and said nose portions, the clearance between the ends of said finger members being less than that between the tips of said nose members for locating rods of smaller diameter beneath said finger members and in said crotch portion and rods of larger diameter between said finger members and beneath said nose portions.

2. A chair as defined in claim 1 wherein said material is selected from the group consisting of nylon, ABS, polypropylene and polyethylene.

3. A chair as defined in claim 1 including a shoulder defined in said web and extending between said wing legs.

4. A chair as defined in claim 3 said web extending in a downward direction from said shoulder and forming a cross foot rail for said chair.

References Cited FOREIGN PATENTS 12/ 1962 Australia.

5 1966 Switzerland. 6/ 1966 Great Britain.

FRANCIS K. ZUGEL, Primary Examiner.

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