Mesh Chair For Concrete Reinforcement

Abstract

A device for maintaining a predetermined space between reinforcement and concrete forms comprises a modular element with support means adapted to receive and retain different sized reinforcing members, such as, wire mesh and includes spaced supporting legs having complementary male and female portions so that elements can be stacked or nested together to vary the spacing between the reinforcement and the concrete forms as well as to support multiple layer reinforcements in spaced predetermined relation to one another.

Description

BACKGROUND OF THE INVENTION

The present invention generally concerns a spacer device for maintaining a predetermined spacing between reinforcement and concrete forms and more particularly concerns a spacer device referred to in the trade as a mesh chair, which is modular in construction whereby identical elements can be stacked to vary the spacing of reinforcement from concrete forms and also to support a plurality of layers of reinforcement if desired.

A number of various types of reinforcement spacers for the support of reinforcement in forms for molding concrete have been used in the industry. The reinforcement, which normally takes the form of wire mesh or fabrics, rigid iron bars, grids or frame work, is employed as skeletal reinforcing for cement and other plastic compositions poured into the forms. The reinforcement is necessary to strengthen the finished compositions and is normally laid out on the concrete form so as to be uniformly spaced a predetermined distance therefrom. The reinforcement frequently covers a large area and must be supported in position as a preliminary to pouring in order to prevent excessive misalignment or bending of the reinforcement.

It is, therefore, desirable that the spacer devices be stable so as not to be easily capsized and have means for firmly gripping the reinforcement so as not to be easily dislodged therefrom. Since the size of the reinforcement varies depending upon the type of construction, it is important that the spacer devices be adapted to be secured to the various sized reinforcement material and it is also desirable that the spacers be devised so that the space between the reinforcement and the form can be easily regulated to conform to various spacings which are needed in the art of casting concrete panels. Where the spacer devices are required to rest against one form, it is also desirable that the area of contact between the spacer and the form be minimized so that there will be a minimum exposure of the spacer device in the face of the finished panel.

Accordingly, it will be appreciated that there are several variables which must be considered in designing a spacer device. In spacer devices now commercially available, for the most part each spacer is specially designed to satisfy specific conditions for a particular type of construction. From an economical standpoint, it is readily apparent that a modular type of spacer device would be desirable in that it would be readily conformable for use under different conditions and applications. In other words, to simplify manufacture and supply and to minimize installation costs, it is desirable that the spacer device be of a single design which is capable of satisfying the various conditions and requirements presented in different applications.

SUMMARY OF THE INVENTION

The spacer device of the present invention is an inexpensive unitary modular member having means for releasably securing the element to reinforcement of several sizes. Preferably the element has four spaced supporting legs defining a relatively broad, stable base so that it is not easily capsized and has a relatively small contact area engageable with or resting on the adjacent form so that there is very little exposure of the element in the finished panel of concrete. The modular element is provided with complementary male and female portions such that elements can be stacked with the male portion of one element mating ith a female portion of an adjacent element whereby a plurality of the elements can be nested to vary the spacing of the reinforcement from the adjacent form. Additionally, the elements are designed to support reinforcement between connected elements so that several layers of the reinforcement can be supported on a single form. The modular elements are of sufficiently high strength that they will not collapse under the weight of the reinforcement and are preferably molded of a plastic material which can be colored or dyed to match the concrete thereby further diminishing the extent to which they are visible in finished concrete panel.

Basically, the modular spacer element includes a body portion with outwardly disposed, spaced depending legs having male portions at one end and complementary female portions at the other end whereby when elements are stacked the male portion of each leg mates with a female portion of an associated leg on an adjacent element to releasably connect the two elements. Each element is also provided with a plurality of retainer arms extending upwardly away from the body so that a reinforcement wire can be held in position between the retainer arms. Each retainer arm is preferably spaced a different distance from the two adjacent arms on either side so that the device can retain and support reinforcement of different types and sizes. The element is provided with bracing and auxiliary supports, and reinforcement wire is constrained to pass directly over the legs of the element to give it maximum strength. However, when elements are stacked and reinforcement is retained between elements, the retainer arms will yield sufficiently to allow the reinforcement to pass slightly to one side of the leg over which it would normally pass so that the male and female portions of legs can be mated.

Accordingly, it is an object of the present invention to provide a reinforcement spacer for concrete construction which is modular and lends itself to application in satisfying various construction variables.

It is another object of the present invention to provide a modular reinforcement spacer for concrete construction wherein a plurality of the spacers when stacked are capable of supporting a plurality of spaced reinforcements.

It is another object of the present invention to provide a reinforcement spacer which leaves very little exposure in the finished concrete panel due to small contact areas between the spacer and the adjacent form.

It is another object of the present invention to provide a modular reinforcement spacer adapted for securement to reinforcement material of various sizes.

It is another object of the present invention to provide a high strength modular reinforcement spacer device which is economical to manufacture and is suited for satisfying numerous variables in concrete panel construction .

BRIEF DESCRIPTION OF THE DRAWING

Other objects, advantages and capabilities of the present invention will become more apparent as the description proceeds taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a fragmentary perspective view with parts broken away showing a concrete form having a plurality of the spacer devices of the present invention supporting a reinforcement mesh.

FIG. 2 is an enlarged fragmentary side elevation with parts broken away of a concrete form illustrating the versatility of the spacer device shown in FIG. 1.

FIG. 2A in a section taken along line 2A--2A of FIG. 2A showing spacer device of the present invention when contorted for use in supporting a plurality of reinforcement.

FIG. 3 is a further enlarged perspective view of the spacer device of the present invention.

FIG. 4 is a top plan view of the spacer device shown in FIG. 3.

FIG. 5 is a vertical section taken along line 5--5 of FIG. 3; and

FIG. 6 is a fragmentary section taken along line 6--6 of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring first to FIG. 1, a typical application of the spacer device or element 10 of the present invention is illustrated. The spacer element 10 is there shown supporting a wire grid reinforcement 12 in uniform spaced relationship from the bottom surface 14 of a concrete form 16. The form 16 also includes side and end panels 18 and 20 respectively, only one of the end panels being seen, so that concrete material 22 can be poured into the form to surround the wire grid reinforcement 12 as well as the spacer elements 10 whereby a finished panel of concrete will be ideally reinforced with the reinforcement grid spaced a preselected distance from the bottom surface of the panel.

A preferred embodiment of the spacer device 10 of the present invention is seen in FIG. 3 to include a body portion 24, peripherally spaced legs 26, and retainer or hook arms 28 for releasably connecting the element to the reinforcement. In the desired form, the spacer device 10 is a completely integrated modular element molded from a plastic material having limited flexibility.

While other configurations could be suitable, the body portion 24, as is best illustrated in FIG. 5, can be seen to be frusto-conical in configuration having an outer conical wall 30 and a top circular surface 32 defining a downwardly opening internal cavity 34. A circular opening 36 passing centrally through the top surface 32 does not serve a functional purpose but is present as a side effect of the particular manner of molding the elements which has been found most suitable.

There are four support flanges 38 extending outwardly from the lower edge of the frusto-conical surface 30, each supporting flange 38 being equally peripherally spaced from the two adjacent flanges. Triangular shaped pairs of upper bracing webs 40 interconnect the frusto-conical surface with the upper surface of the flanges to give added vertical strength to the flanges.

The legs 26 of the spacer device depend downwardly from the flanges 38 and comprise substantially cylindrical supports having pilot portions 42 of reduced diameter at their lower terminal ends. Circular passages 44 are provided through the support flanges 38 and align with hollow central portions 46, FIG. 5, of the legs. The passages 44 have a diameter substantially the same as the diameter of the pilot portion 42 of each leg so that the pilot portions of one spacer element can be inserted into the passages 44 of an identical underlying element whereby two of the elements can be releasably connected in stacked relationship.

As is best seen in FIG. 5, triangular shaped pairs of lower bracing webs 48 interconnect the cylindrical sides of each leg 26 with the undersurface of the associated supporting flange 38 to provide lateral support for the legs. Since the legs 26 support the spacer element as well as the reinforcement grid 12 which is connected to the elements, an upward force is placed on the supporting flanges 38 by the legs 26 and the upper bracing webs 40 serve to transmit the vertical force substantially horizontally into the body of the element. Therefore, the upper bracing webs 40 along with the lower spacing web 48, which give lateral support to the legs, strengthen the elements so that they will not collapse under excessive pressures such as are exerted thereon by the weight of the reinforcement grid and the weight of workers walking upon the reinforcement grid.

The pilot portions 42 of each leg 26 have a relatively small diameter and are adapted to rest against the bottom 14 of the form 16 so that there is very little contact area between the spacer elements and the form. This, of course, is important since when the concrete panel is finished, the only exposure of the spacer elements will be at the relatively small contact areas at the ends of the legs and these will be virtually unnoticeable, particularly when viewed from a distance.

There are four retainer or hook arms 28 which are spaced around the top surface 32 of the elements 10 and which protrude upwardly from the top surface. Each of the hook arms 28 is wedge shaped tapering upwardly in an inner radial direction to give it radial support. Upwardly extending bracing ribs 50 are provided on both sides of each hook arm to give the arms lateral support. Each hook arm 28 has a radially inwardly extending nose 52, FIGS. 5 and 6, defining an overhang 54 which in cooperation with a substantially vertical inner surface 56 of the arm defines one side of a radial passage 58 or 60, FIG. 4, which passes between adjacent arms 28 on diametrically opposed sides of the element and which is adapted to receive a reinforcement wire. The overhangs 54 of two adjacent hook arms 28 serve to retain the reinforcement wire within the defined passage 58 or 60. The plastic material from which the spacer element 10 is made has limited flexibility so that the reinforcement wire can be forced down between adjacent nose portions 52 of the hook arms and once in the included passage, will be retained therein by the overhangs which will immediately return to their normal positions.

As can be best appreciated with reference to FIG. 4, each hook arm 28 is spaced a different distance from the two adjacent hook arms so that a hook arm will be closer to one adjacent hook arm than to the other. This arrangement makes the two mutually perpendicular passages 58 and 60 across the top of the elements a different width so that a variety of reinforcement wire sizes, two being shown by dotted lines in FIG. 4, can be accomodated with the spacer element. The passages 58 and 60 are aligned with diametrically opposed legs of the element such that wire retained in either passage will pass directly over two of the legs for maximum support. Since the hook arms 28 have limited flexibility, several reinforcement sizes can be accomodated by both passages. In other words, a reinforcement wire which is small enough will fit easily down into either passage while reinforcement wires which are slightly larger will also fit into the same passage but will be more tightly received. The same is true of the other passage so that numerous reinforcement sizes are accomodated.

As mentioned previously, it is preferable that the spacer elements 10 be molded of a plastic material with limited flexibility so that the reinforcement wires can be snapped into the passages between the hook arms for best retention. Being made of a plastic material, the spacer elements can be dyed or colored to blend with the finished concrete panels so that the small contact areas on the end of the pilot portion 42 of each element will be virtually unnoticeable in the finished product. A recent trend in prefabricated construction techniques has been to spread a layer of colored aggregate on the bottom surface of the forms before pouring the concrete so as to create a more decorative colored aggregate face on the finished panel. The spacer element of the present invention is particularly well suited for use in this type of prefabricated construction in that the spacer can be colored or dyed to match the color of the aggregate and has a relatively large clearance between the body of the element and the lower supporting form so that it will sit over the aggregate while being supported by the form.

If it is desired to use the spacer elements 10 to support a plurality of spaced reinforcement wire grids 12, as shown in FIG. 2, wherein several of the spacer elements are stacked on top of each other with the wire gird passing between adjacent elements, the limited flexibility of the hook arms 28 allows them to flex slightly, FIG. 2A, so that the wire does not pass directly over legs 26 of a lower element and prevent the pilot portions 42 of the legs on an upper element from being received in the sockets or passages 44 of the legs of the lower element. The various applications of the element in this regard are illustrated in FIG. 2. At the far left of FIG. 2, a single spacer element is shown utilized to support a single layer of reinforcement 12 while in the center two of the elements are stacked supporting two spaced reinforcement grids 12. At the far right four of the spacer elements are shown with a wire reinforcement grid 12 passing between each spacer so that four reinforcement grids with relatively narrow spacings are supported.

Accordingly, it can be appreciated from the foregoing description that the modular unitized spacer device or element 10 of the present invention is highly versatile. Not only is it designed for high strength applications whereby each of the supporting components of the device is structurally braced, but it is also suited for varying the spacing of a single layer of wire reinforcement from the bottom of the concrete form or for supporting a plurality of spaced wire reinforcements on the bottom of the form. In this relation, the spacing of the reinforcement from the bottom of the form can also be varied merely by altering the length of the pilots 42 and such variations can be easily made in the molding operation. A particularly valuable asset of the spacer element is that the various foregoing advantages are achieved with modular units of a single design so that molding costs are minimized and a worker does not have to select from a variety of spacing elements when putting the elements to use and can merely utilize the one element design in its numerous possible applications to give the desired results.

Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made by way of example and that changes in details of structure may be made without departing from the spirit thereof.

Claims

What is claimed is:

1. A chair adapted for supporting wire reinforcement in a concrete form comprising a unitary member including a main body portion, flange members disposed at equally spaced intervals around said body portion, a leg portion depending downwardly from each of said flanges in a common direction and in spaced parallel relation to one another, each leg portion terminating in a lower end portion of reduced size, and socket means in each flange adapted to receive the lower end portion of each leg portion of a second corresponding chair whereby to permit a pair of said chairs to be nested together, and retainer means on said body portion defining at least one wire-receiving passage for releasably retaining a portion of the wire reinforcement therein.

2. A chair according to claim 1, said retainer means defined by a plurality of arms directed inwardly toward one another, said arms being spaced apart to form mutually perpendicular passages for the reception of wire mesh reinforcement.

3. A chair according to claim 2, said arms being spaced unequal distances apart to form mutually perpendicular passages of differing widths for the reception of wire mesh reinforcement of different sizes, said retainer means adapted to retain the wire mesh reinforcement in place against the body portion of said chair.

4. A chair according to claim 2 wherein said retainer means is composed of a material of limited flexibility to permit the wire mesh reinforcement to be snapped into the wire-receiving passages.

5. A chair according to claim 1 further including bracing means for said flanges, said bracing means extending between said body portion and said flanges.

6. A chair according to claim 1, wherein said retainer means comprise a plurality of circumferentially spaced arms having hook-shaped outer ends adapted to hook over said reinforcement.

7. A chair according to claim 1 wherein said body portion is of generally circular configuration and has a central opening extending therethrough in a direction parallel to said legs, said flange members extending radially outwardly from said main body portion.

8. A chair according to claim 1, said retainer means extending from said body portion in a direction opposite to said leg portions.

9. A chair according to claim 1, said socket means communicating with hollow portions in each of said legs.

10. A mesh chair adapted for supporting wire mesh reinforcement comprising a unitary member having a generally circular body portion, flange means extending radially away from said body portion at equally spaced intervals, a plurality of circumferentially spaced legs depending from said flange parallel to the axis of said body portion, bracing means interconnecting said flange means and the body portion and interconnecting said flange means and the legs to reinforce said legs and said flange means, pilot means on the free ends of said legs having arcuate lower ends, socket means in said flange adapted to receive the pilot means of a second corresponding chair, and retainer means extending from said body portion in a direction opposite to said legs, said retainer means being defined by a plurality of arms directed inwardly toward one another, said arms being spaced unequal distances apart to form mutually perpendicular passages of differing widths for the reception of reinforcement of different sizes, said arms being adapted to retain the reinforcement in place against the body portion of the chair.