US3623289A - Flexible spacing device for concrete reinforcing materials - Google Patents

Abstract

A NEW AND IMPROVED FLEXIBLE SPACING DEVICE OR SPACER, USED WITH CONCRETE REINFORCING MATERIALS, E.G., WIRE MESH, REINFORCING RODS, BARS AND THE LIKE, FOR SPACING THE LATTER IN FIXED PARALLEL PLANE RELATIVE TO A WALL OR SURFACE ON WHICH PLASTIC AND PLASTIC-LIKE COMPOSITIONS, SUCH AS CONCRETE, ARE TO BE POURED AND SET TO FORM SLABS. THE SPACING DEVICE HOLDS, E.G., THE WIRE MESH OR REINFORCING ROD, WHICH IS TO BE INCORPORATED WITHIN THE CONCRETE SLAB, IN A PREDETERMINED POSITION OUTWARDLY FROM THE PLANE FORMED BY THE WALL OR SURFACE, WHICH CAN BE HORIZONTAL, VERTICAL OR DIAGONAL, REGULAR OR IRREGULAR. THE SPACING DEVICE IS CONSTITUTED OF AN ELASTIC OR RESILIENT MATERIAL, PREFERABLY PLASTIC, AND COMPRISES A LEG, GENERALLY A CYLINDRICALLY SHAPED PORTION UPON A TERMINAL END OF WHICH IS PROVIDED A NOTCHED SUPPORT SURFACE FOR HOLDING THE WIRE MESH OR REINFORCING RODS OR BARS. PREFERABLY, THE NOTCHED SUPPORT SURFACE IS CONTAINED WITHIN AN ENLARGED HEAD, AND THEREON IS PROVIDED A PAIR OF INTERSECTING NOTCHES, CONTAINING KEY SLOT OPEININGS AT THE BOTTOM PORTIONS THEREOF TO FORM LOBED SURFACES WHICH INTERLOCK WITH THE WIRE MESH, REINFORCING RODS AND THE LIKE. THE LOWER FACE OF THE ENLARGED HEAD IS GENERALLY FLAT, PREFERABLY TO PROVIDE A BEARING SURFACE FOR USE OF A PLIER-LIKE TOOL, IN SECURING THE SPACING DEVICE TO THE WIRE MESH OR CONCRETE REINFORCING ROD.

Description

Nov. 30, 1911 J. 1.. LOWERY 3,623,289

FLEXIBLE SPACING DEVICE FOR CONCRETE REINFORCING MATERIALS Filed Nov. 12, 1969 INVE T)R. JOHN L. LOWE BY gmw u 1 4 (EL ATTORNEY United States Patent 3,623,289 FLEXIBLE SPACING DEVICE FOR CONCRETE REINFORCING MATERIALS John L. Lowery, 955 Magnolia Wood Ave., Baton Rouge, La. 70808 Filed Nov. 12, 1969, Ser. No. 875,995 Int. Cl. E04c 5/16 US. Cl. 52-309 9 Claims ABSTRACT OF THE DISCLOSURE A new and improved flexible spacing device or spacer, used with concrete reinforcing materials, e.g., Wire mesh, reinforcing rods, bars and the like, for spacing the latter in fixed parallel plane relative to a wall or surface on which plastic and plastic-like compositions, such as concrete, are to be poured and set to form slabs. The spacing device holds, e.g., the wire mesh or reinforcing rod, which is to be incorporated within the concrete slab, in a predetermined position .outwardly from the plane formed by the wall or surface, which can be horizontal, vertical or diagonal, regular or irregular. The spacing device is constituted of an elastic or resilient material, preferably plastic, and comprises a leg, generally a cylindrically shaped portion upon a terminal end of which is provided a notched support surface for holding the wire mesh or reinforcing rods or bars. Preferably, the notched support surface is contained within an enlarged head, and thereon is provided a pair of intersecting notches, containing key slot openings at the bottom portions thereof to form lobed surfaces which interlock with the wire mesh, reinforcing rods and the like. The lower face of the enlarged head is generally flat, preferably to provide a bearing surface for use of a plier-like tool, in securing the spacing device to the wire mesh or concrete reinforcing rod.

It is well known to use various styles and forms of spacing elements for supporting and retaining concrete reinforcing materials, e.g., Wire mesh, reinforcing rods, bars and the like, in elevated position while pouring and forming plastic and plastic-like forms, e.g., concrete slabs. Most are rigid members, constructed of metal; generally, iron or steel. These spacing elements, generally referred to as chairs, hold the wire mesh or rods above and away from the foundation or surface upon which the slab to be formed to enhance the strength of the finished slab. When the wet concrete is poured, the latter covers both the supports and the wire mesh or reinforcing rods; and all becomes a part of the finished slab after the concrete has set.

In such constructions it is particularly important to properly position the wire mesh or reinforcing rods within the slab to enhance its strength. The problems associated with proper positioning of wire mesh and reinforcing rods in horizontal slab constructions has been particularly difficult in the past because even after positioning these members at an optimum location within a stab, they are often skewed out of place, bent about the supports or pressed close to the ground by careless workers. Or, as often happened, even the supports themselves were physically forced, or pushed, into the ground or through protecting waterproof membranes. This problem, however, has been largely overcome by the use of multileg flexible supports composed of resilient materials, whereby upon application of an unbalanced force upon, e.g., the bar, the legs of the support deform so that the bar is displaced downwardly. And, upon removal of the deforming force, the legs rebound to their initial condition to return the bar to its original preselected elevation. Such supports, disclosed and claimed in my US. Fat.

ice

3,368,320, issued Feb. 13, 1968, have proven admirably suitable for this purpose, but, nonetheless, further improved supports are desired.

One type of construction which yet poses especially diflicult and acute problems thus relates to the formation of slabs between parallel walls, particularly parallel vertical walls, as is necessary in poured-in-place walls, tilt-up constructions, pre-cast work and in placing wire in forms for making pipe. In such constructions it is necessary to properly position or space the wire mesh or concrete reinforcing bars outwardly from the walls. This is particularly difficult with wire mesh. The unrolled wire mesh, e.g., which has a tendency to curl and kink, must often 'be lowered downwardly between pairs of walls. In so doing, it is generally found necessary to cut openings in one of the walls to gain access to straighten, properly space and se cure the wire in proper position within the walls. There is yet a need, in the art, therefore, for new and improved spacer devices, particularly spacer devices for use in these types of constructions.

Accordingly, it is a primary objective of this invention to provide a new and improved flexible spacing device for the foregoing and additional usages of even greater simplicity of design and construction.

A specific object is to provide a new and novel flexible spacing device particularly adaptable for use in vertical, diagonal and irregular wall type constructions.

A more specific object is to provide such spacing device which will not tarnish or rust to preserve the appearance of the face of the slab construction.

A further object is to provide a spacing device of such character which can be conveniently constructed by extrusion and injection molding, particularly adaptable for use with wire fabrics, reinforcing rods and bars, and the like.

A yet further object is to provide a tool for placement of such spacing devices on wire mesh or reinforcing rods.

These objects and others are achieved in accordance with the present invention, a flexible spacing device, or spacer, comprising a generally cylindrical shaped portion, constituting a leg, at a terminal end of which is provided a notched support surface for holding the wire mesh or reinforcing rod or bar. The spacer is composed or constructed of elastic or resilient material to provide a combination of sound stability and yielding spring-like elasticity.

The notched portion of the spacing device is preferably enlarged to form a head, and more preferably the underside of the head is squared or flattened to provide a bearing surface so that the spacing device can be used with a tool for securing the said device to a wire mesh or reinforcing rod. The upperside of the head is provided with a pair of notches, one at right angles to the other, for better securing the support to either side of intersecting wire portions of the mesh, or for attachment to a bar.

A key and novel feature of the invention is that the utility of the support is greatly enhanced, as contrasted with my previously disclosed multi-leg supports, supra. The present supports have been reduced to the ultimate in their simplicity and design. Yet they are not only usable for those constructions for which the former multi-leg supports were designed, but provide even greater utility in their outstanding capacity for use in diagonal, vertical and irregular wall type constructions.

These and other features and advantages will be better understood by reference to the following detailed description and to the accompanying drawings to which reference is made in the description.

Referring to the drawings:

FIG. 1 depicts a top or plan view of a preferred type of spacing device, loking downwardly upon the head;

FIG. 2 depicts in half-section an elevation view, taken along lines 22 of the preceding figure of the support;

FIG. 3 depicts a preferred use of the spacer devices for positioning a wire mesh at a desired location between the walls of a vertical form (which could also be a diagonal or irregular form) within which concrete is to be poured and set; and

FIG. 4 depicts a preferred form of tool useful for affixing the spacer devices to, e.g., wire mesh.

Referring to FIGS. 1 and 2, there is shown a preferred type of spacer comprising a leg 11, which is generally a cylindrical portion, which carries an enlarged portion or head 12. The underside, or lower face, 12A of the head 12 is flat to provide a suitable bearing surface for grasping with special plier-like tools, hereinafter described, used for affixing the supports upon wire mesh, concrete reinforcing rods and the like. The upper side, or upper face 12B, of the head 12 is provided with a pair of grooves or notches 13, 14, one at right angles to the other, and extending across the head diameter. It will be observed that one of the notches 14 is cut deeper into the head 12 than the other notch 13, and that the lower portions of the notches 13, 14 are enlarged to form key-hole slots. The notches 13, 14 are cut in this fashion to provide lobed surfaces which is actually a snap-on or lock feature to facilitate attachment of the spacers 10 to the junctures formed by the intersecting wires of a standard concrete reinforcing wire mesh, one wire of which is raised by passage over the others. On the other hand, the head is as easily secured to a concrete reinforcing rod or bar. The lower portion of the leg 11 is preferably frusto conical shaped to provide a small area contact surface, this minimizing visible spots or marks which might appear in the surface of a finished slab.

FIG. 3 shows the use of a plurality of the spacing devices 10 through 10 secured, locked tightly, and alternately arranged upon the intersections of wire 41, 42; 41, 43; 41, 44; 41, 45; and 41, 46 to maintain a desired spacing of the wire between both of the vertical walls 15, 16. By such means concrete can be poured and set between the walls 15, 16 without concern of dislocation of the wire mesh. The supports are equally suitable for use in diagonal or vertical structures, and their high degree of resiliency prevents their displacement from the junctures to which they are attached.

Spacers which are constructed of resilient plastics offer outstanding advantages. These structures are highly resilient, do not tarnish or rust, and can be formed, e.g., by extrusion and injection molding, in various shapes and then used as initially formed or reshaped upon attachment to the rigid reinforcing bars, grids or frameworks for the support thereof.

The resilient plastic compositions most suitable for use in accordance with the present invention are those low density, high molecular weight polymers having a crystalline or partially crystalline structure. Generally, the molecular weight of the polymer should range from about 50,000 to about 100,000, and higher, and the degree of crystallinity at least about 10 percent, or higher. More preferably, however, the molecular weight ranges from about 100,000 to about 200,000, and above, and crystallinity ranges from thirty to about seventy percent, and above. Such plastics can be modified by the addition of stabilizers, molding powders and the like to provide the proper resiliency. Polyvinylchloride and polypropylene are particularly suitable from a cost-effectiveness standpoint. An advantage of such plastics is that, generally, even off-specification products can be used quite effectively. Iron and steel in resilient form, however, can be used in formation of these spacing devices.

Referring to FIG. 4, there is shown a plier-like tool especially adapted for use in securing the spacer devices 10 to intersecting wires 51, 52, one of which is crossed over the other, of a wire mesh. The plier-like tool is provided with a pair of levers, providing handles 54, 55, pivotally connected together via a stud or bolt 56 intermediate their lengths. At the opposite ends of the levers 54, 55 there is provided a pair of oppositely disposed jaws 57, 58 which can be forcibly brought together by action on the ends of levers, or handles 54, 55, which tend to bring these members together. The lower portion of the jaw 58 is bifurcated, providing a pair of members 58 58 which fit underneath the flat portion of the head 12 of a spacer device 10 holding the latter tightly in place while force is applied downwardly at the intersection of the wires 51, 52 via force applied thereon through the knobbed or bulged surface 59 of the top jaw 57 so that the lobed surface of the spacing device 10 can be locked at the intersection of the wire mesh. The tool greatly facilitates the securing of the spacers 10 to Wire mesh or concreate reinforcing rods, this being a very diflicult task when performed by hand.

It is apparent that various changes, such as in absolute or relative dimensions of the parts, materials and the like, can be made without departing the spirit and scope of the invention, as will be apparent to those skilled in the art.

It is also apparent that the spacing device can be used in various ways, and in such manner as to provide advantages over other types of spacing device now in use. For example, as will be apparent to those skilled in the art, the spacing devices of this invention can be secured or fastened onto wire mesh outside of the form within which the mesh is to be used, and then dropped or lowered into place within the form. In descending between a pair of walls the spacer devices, due largely to their inherent resiliency do not rotate, become dislodged or fall off the wire mesh. Instead, the spacing devices hold fast at the joint of the wires, and remain perpendicular to the plane of the wire.

It is no longer necessary to precast work, in constructing horizontal forms, to hand wire fabric, and consume time and energy in raising and tying the wire fabric up at spaced intervals, to avoid its lying at the bottom of a form. Also in constructing Vertical forms, the spacer devices can be used to hold the wire mesh at the proper distance from each form, at the desired locations. Much of the precast work is prefabricated with both wall forms located properly. The wire is dropped in from the top, and the spacers used. After setting, the forms can be removed for use in further prefabrications.

It now also becomes easier in constructing horizontal forms to finish the tops of precast slabs. In present practice, to prevent the blemishes, the wire may now be hung from the top. The support wires which are used to hang the mesh in position within the form prevent easy finishing of the top of the finished slab. The support wires are also difficult to cut off after the construction is completed, and rust on the inside to form unsightly blemishes. Now, the top of the slabs can be readily finished because hanging wires are eliminated, and offer no interference.

Unsightly spots and images which all too often make their appearance in the face of such prior art precast construction now virtually disappear due to the very small point or tip of the present spacing device, even though it may rest at or very near the bottom of the form,

The point contact provided by the preferred spacing devices is also advantageous when used in relatively coarse slab forming areas, and the notched heads themselves readily grasp, support and hold securely to wire mesh even when the key slot openings of the notches are larger than the diameter of the wires upon which they are secured.

Having described the invention, what is claimed is:

1. A spacing device for securing to a rigid concrete reinforcing structure to position and maintain the said concrete reinforcing structure in preselected position between a pair of vertical walls for formation of a slab construction comprising a single elongate member of relatively small diameter as contrasted with its over-all length constituted of a resilient plastic material deformable to some extent to provide suflicient resiliency to prevent its ready dislodgement from the structure to which it is secured, an enlarged head at a terminal end of said elongate member, said head having a flat underside at the juncture wherein the head adjoins the elongate member, and a pair of deep notches within the upperside of the said enlarged head, said notches intersecting at right angles one to the other, and one notch of the pair being cut deeper into the head than the other.

2. The spacing device of claim 1 wherein the bottom portions of the notches are provided with key-shaped slots, providing lobed surfaces which snap onto the structure to which it has been secured.

3. The spacing device of claim 1 wherein the material of which the device is constructed is a plastic composition of molecular weight ranging from about 50,000 and higher, and the material possesses at least about ten percent crystallinity.

'4. The spacing device of claim 3 wherein the material of construction is selected from the group consisting of polyvinylchloride and polypropylene.

5. In combination, apparatus comprising a rigid concrete reinforcing structure, and a spacing device to which it is secured, the latter member comprising a single elongate member of relatively small diameter as contrasted with its over-all length constituted of a resilient plastic material deformable to some extent to provide sufiicient resiliency to prevent its ready dislodgement from the concrete reinforcing structure, an enlarged head at a terminal end of said elongate member, said head having a fiat underside at the juncture wherein the head adjoins the elongate member, and a pair of deep notches within the upperside of said enlarged head, said notches intersecting at right angles, one to the other, one notch of the pair being cut deeper into the head than the other, the bottom portion of each being provided with key-shaped slots, providing lobed surfaces which snap onto the concrete reinforcing structure.

6. The combination of claim 5 wherein the spacing device is constructed of a plastic composition of molecular weight ranging from about 50,000 and higher and the material possesses at least about ten percent crystallinity.

7. The combination of claim 6 wherein the spacing device is constructed of a material selected from the group consisting of polyvinyl chloride and propylene.

8. The combination of claim 6 wherein a plurality of the spacing devices are alternately arranged on opposite sides of the wire mesh, and the wire mesh is vertically suspended.

9. The spacing device of claim 2 wherein the upper side of the enlarged head is rounded to facilitate access of the reinforcing structure into the pair of notches to secure the said spacing device to the said reinforcing structure.

References Cited UNITED STATES PATENTS 1,356,315 10/1920 Scofield 52687 X 1,672,852 6/1928 Roughan 52677 3,447,277 6/1969 Korf 52687 3,368,320 2/1968 Lowery 52684 3,290,842 12/1966 Aberg 52689 FOREIGN PATENTS 1,300,528 1962 France 52688 36,828 1913 Sweden 52684 211,591 1966 Sweden 52685 JOHN E. MURTAGH, Primary Examiner US. Cl. X.R. 52677, 685

Images