Lightweight Concrete Cladded Heavy Equipment Base

1. Field of the Invention

This invention relates to pads for the support of heavy equipment such as air conditioners, heaters and transformers.

2. Discussion of Related Art

The high cost of poured onsite concrete bases for various types of air conditioning, heating and electrical equipment has given rise to a growing market of precast concrete bases. Although such precast bases are usually less expensive than site poured bases, they are generally very heavy requiring heavy equipment or several laborers to set into place. Precast concrete bases are also expensive to ship and thus lose their cost advantage when transported to points at much greater distances than those within the local area.

Certain substitutes for precast concrete bases have been suggested. For instance, U.S. Pat. No. 4,050,659, issued Sept. 27, 1977, shows a transformer pad having a fiberglass reinforced plastic exterior surface and an expanded foam core. U.S. Pat. No. 4,023,755 issued May 17, 1977 to Alesi, Jr., shows a transformer mounting pad wherein structural support for the load is provided by a wood and foam core enclosed within a plastic shell, U.S. Pat. No. 3,772,845, issued May 27, 1973 to Unger, shows a ground mounting base for use with heat exchanger units. The base comprises a pad of concrete employing vermiculite as its primary aggregate, a wire screen reinforcement, and a top layer of sand aggregate concrete. U.S. Pat. No. 3,713,620, issued Jan. 30, 1973 to Tkach, shows a machine supporting slab formed of a rigid body of closed-cell foam resin material of high density covered by a metal sheath spanning the top and extending around the marginal edges of the body.

One object of the present invention is to provide a heavy equipment base which appears to be an ordinary solid concrete slab but which is in fact a low density material cladded with fibered concrete.

A further object of the present invention is to provide a heavy equipment base which is 1/16-1/8 the weight of an ordinary concrete base of the same size thus allowing ease of handling by installation personnel.

Yet another object of the present invention is to provide a heavy equipment base which is formed with a cushion on the bottom in order to allow a plurality of the bases to be stacked one upon another for shipment without need of protective spacers between the base. Also, by virtue of the padded bottom, less smoothing of the ground upon which the base is to rest is required since the base will more readily conform to the shape upon which it is set.

An even still further object of the present invention is to provide a heavy equipment base which is less subject to breakage than ordinary concrete bases.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.

FIG. 1 is a perspective view of the lightweight concrete cladded heavy equipment base with a portion broken away showing the foam core.

FIG. 2 is a perspective view of a lightweight concrete cladded heavy equipment base provided with threaded inserts mounting vertical stanchions.

FIG. 3 is a perspective view of a lightweight concrete cladded heavy equipment base formed for use as a transformer pad.

Now with reference to the drawings, a lightweight concrete cladded heavy equipment base incorporating the principles and concepts of the present invention and generally referred to by the reference numeral 10 will be described in detail. Base 10, as seen in FIG. 1 comprises a substantially rectangular core 12 which is a polystyrene foam board, polyurethane foam board, urea-formaldehyde foam board or other low density insulating board having a compressive stength range of 1000-20,000 lbs. per sq. ft. The preferred material for core 12 is polystyrene foam since this is not subject to attack by soil conditions, fungus, bacteria, insects, or moisture, and will last indefinitely unless exposed to high temperatures (above 200.degree. F.) and certain strong solvents and/or direct sunlight. The core 12 is provided with bevelled upper edges shown at 14 in order to increase the thickness of the concrete coating 16 which covers the core in that area. Concrete coating 16 is a fiberglass/cement composition using alkali resistant fiberglass strands. Non-alkali resistant glass and organic fibers may be used for a generally less durable product. The fiberglass coating can be any known composite and can be applied in any known manner as described, for instance, in U.S. Pat. Nos. 3,785,621; 3,852,082, 3,716,386; and 3,783,092. The coating 16 is applied around the sides of core 12 and over the top surface of the core leaving the bottom of the core exposed. The coating 16 is preferably 3/4 of an inch thick at the bottom 20 and tapers to 1/2 inch thick just below the bevel in the area generally labelled by the reference numeral 22. The top of the core 12 has a 3/8 of an inch thick layer of concrete applied thereto. In addition to the general reinforcing throughout the cement phase by alkali resistant fiberglass strands, steel rods 24 can optionally be embedded around the bottom of the coating 16 running parallel to the sides of core 12. While not necessary, a thin coating of cementitious material may also be applied to the core bottom, if desired.

By use of the low density polystyrene core 12, the base 10 will ultimately be of 1/6-1/8 the weight of an ordinary concrete base of the same size. Thus, a plurality of bases 10 can be shipped typically three to five times the distance for the same cost as an ordinary concrete slab of the same size. The bases can also be stacked one upon the other and shipped by conventional means without use of protective spacers between the bases since the exposed bottom of the foam core 12 acts as a cushion preventing damage to the top surface of the base stacked beneath the exposed bottom. The exposure of the bottom of the core 12 also allows for easier installation of the base since the polystyrene will conform to a ground configuration thus requiring less smoothing than that necessary for the installation of ordinary concrete bases.

Access recesses, mounting studs and threaded recesses as well as wires, tubing and stressed reinforcing cables may be built into the bases. As one example of the use of a threaded recess, FIG. 2 shows a base 10'. Base 10' is similar in every respect to base 10 including core 12 covered by coating 16. Base 10' is adapted to receive a heat pump and therefore is provided with a plurality of mounts 30. Each mount 30 comprises a threaded steel post 32 welded to a steel bearing plate 34. Steel bearing plates 34 are preferably 21/2".times.21/2".times.3/16" and are capped by a mastic material to insure a noiseless, secure mounting for the heat pump outdoor unit. The posts 32 are preferably provided in varying the heights from 8"-24" and each post is individually adjustable thereby allowing a level, vibration free installation. Heavy steel coils 36 forming threaded inserts are embedded in the composite concrete coating 16 to receive the threaded post 32 with the composite coating 16 including integral depending bosses 38 which are preferably 3 inches in diameter and formed from the fiberglass cement composite and are cast in one piece with the coating 16.

As a final example of a base constructed according to the present invention, FIG. 3 shows a base 10" configured to receive a transformer. Accordingly, base 10" has the same core and coating as base 10 but formed with an upwardly opening recess 40 to receive a transformer. Other types of equipment may be placed on bases constructed according to the invention. Such equipment includes pumps, filters, compressors, engines, motors, electrical switching equipment, telephone booths, etc. as can be seen by one of ordinary skill in the art, the base shape can be altered to receive any of this equipment and, as mentioned hereinabove, studs, wires, etc. can be molded into the base as required.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.