Abstract:
A tie for insulated concrete forms that has a Z-bend configuration so that the tie is nestable with similar Z-bend ties in order to optimize the cubic volume and the weight of a container of nested ties for shipment.

Description:
RELATED APPLICATION 
   This application claims the benefit of priority of U.S. provisional application Ser. No. 60/589,732, filed Jul. 21, 2004, which is relied on and incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The present invention relates to insulated concrete forms (“ICF”) and particularly to the ties used in such ICFs. 
   BACKGROUND OF THE INVENTION 
   ICFs generally comprise two walls or slabs of foam (usually expanded polystyrene foam (“EPS”)) held apart a defined distance by a series of ties. An ICF is used to construct a one-piece, monolithic concrete wall with reinforced concrete posts and beams. The ICF remains in place and provides an energy efficient concrete wall that can be finished with conventional interior and exterior wall coverings. The ties serve to space the two foam walls of the ICF a uniform distance apart and to prevent the walls of the ICF from spreading as the hydraulic pressure of the wet concrete fills the form. A conventional ICF with conventional ties is shown in  FIGS. 1-3 . 
   The conventional ICF  10  shown in  FIGS. 1-3  consists of two walls  12  and a plurality of ties  14 . Each tie  14  is comprised of crosstie elements  16  and reinforcing elements  18 . The ties  14  shown in  FIGS. 1-3  hold the walls  12  in place as concrete  5  is poured into the ICF  10 . Further, as shown in  FIGS. 1 and 3 , the ties  14  may have a furring strip  15  connected to, and extending along each side of, the crosstie elements  16  of the tie  14 . Each furring strip  15  generally consists of a solid sheet of plastic or metal. The furring strips  15  give greater resistance to wall separation during concrete  5  pouring and also serve as anchor strips into which screws or other fasteners may be inserted to hold finish materials such as drywall or siding to the outside of the form walls  12 . 
   The prior art ties  14  are made either of injection molded plastic or formed or welded wire and sheet metal. As shown in  FIG. 2 , the prior art ties  14  are bent into a conventional U-shaped configuration before the ties are molded into the foam block walls  12  of the ICF  15 . The ties  14  are bent into the conventional U-shaped, or an H-shaped configuration, either at the time they are made or in a subsequent forming operation. 
   These conventional U-shaped and H-shaped configurations are designed to meet criteria related to the function of the ICF. The conventional U-shaped and H-shaped ties do not, however, result in efficient shipping configurations. Particularly, the conventional U-shaped and H-shaped ties tend to fill up the available cubic volume in a transport vehicle long before the weight limit of that vehicle is reached. This increases freight, warehousing, and handling costs of the conventional U-shaped and H-shaped ties, as well as scrap due to damage, between the point where the ties are made and the point where the ties are molded into the ICF. 
   One attempted method to solve the problem outlined above is shipping and handling the ties in a flat configuration before the ties are formed into the conventional U-shaped or H-shaped configuration. The flat ties are then formed into the conventional U-shaped or H-shaped configuration at the EPS molding site or at a nearby third party. Difficulties are encountered with shipping ties in a flat configuration because EPS molders typically do not have forming or die bending experience (resulting in inefficient operations and high waste), and the use of third party benders increases the length of the supply chain resulting in more work in progress inventory, increased handling costs, and lack of single point responsibility for quality control. 
   SUMMARY OF THE INVENTION 
   The present invention overcomes the problems above by means of a Z-bend, nestable tie design. The Z-bend ties nest within each other so that the weight and cubic volume limits of conventional shipping containers are efficiently matched. 
   According to one aspect of the present invention a tie is provided for an ICF comprising a first planar section of intersecting elements, the first planar section having a first side, a second side, a first end, and a second end; a second planar section connected to the first side of the first planar section at approximately a right angle; a third planar section connected to the second side of the first planar section at an angle greater than 90 degrees; and a fourth planar section connected to the third planar section at an angle less than 90 degrees. 
   In one embodiment, a first furring strip is connected to the second planar section of the tie. Likewise, a second furring strip may be connected to the fourth planar section of the tie. 
   According to another aspect of the present invention a tie is provided for an ICF comprising at least one crosstie element and at least one reinforcing element. Each crosstie element has a first side section, a central section, and a second side section. The second side section comprises a first portion connected to the central section at an angle greater than 90 degrees and a second portion connected to the first portion at an angle less than 90 degrees. Each reinforcing element is connected to the central section of at least one crosstie element. 
   In one embodiment, a first furring strip is connected to the first side sections of the crosstie elements. Likewise, a second furring strip may be connected to the second side sections of the crosstie elements. 
   When the Z-bend ties of the present invention are used with molded EPS walls of an ICF, no visible difference is apparent to the end user of the forms. Further, the Z-bend ties can be used in the existing EPS molding dies, thus allowing immediate use without expensive tooling modifications. 
   Importantly, the Z-bend ties are nestable which allows for much lower transport costs for the Z-bend ties. Consequently, the Z-bend ties can be made and formed at one factory and shipped worldwide for use at multiple EPS molding plants. For instance, for the conventional U-shaped ties, the number of U-shaped ties which fit in a 40 ft. container is between 14,820 and 44,400, depending upon exact tie size. With the Z-bend tie of the present invention, that range for a 40 ft. container is 33,120 to 73,600 ties, a number which reaches the weight limit for containers at about the same point the cubic volume limit is reached. 
   In addition, the nesting action of Z-bend ties tends to reinforce each other in the nested stack, giving a synergistic effect which makes each individual tie as strong as the nested stack. Consequently, nesting of the Z-bend ties greatly cuts down on handling damage and the resulting waste experienced with the prior art conventional U-shaped or H-shaped ties which are much more vulnerable to damage during transport. 
   Moreover, The Z-bend ties can be made and formed at one facility, improving quality control and shortening the supply chain. The Z-bend configuration and advantages work for either bent or formed metal ties or injection molded plastic ties. 
   All of the above is accomplished without the need for equipment modifications to use the new Z-bend tie, and without alerting the end-users that any changes have been made to the insulated concrete form. The functionality of the Z-bend tie, in terms of holding the forms in place, resisting separation, anchoring finish materials is unchanged from that of the conventional U-shaped and H-shaped ties. 
   Further objects, features and advantages will become apparent upon consideration of the following detailed description of the invention when taken in conjunction with the drawing and the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of the prior art ICF with cutaway portions to show conventional, prior art ties. 
       FIG. 2  is a top plan sectional view of the prior art ICF illustrated in  FIG. 1 . 
       FIG. 3  is a front sectional view of the prior art ICF illustrated in  FIG. 1 . 
       FIG. 4  is a perspective view of a Z-bend tie in accordance with the present invention with furring strips. 
       FIG. 5  is a top plan sectional view of an ICF with Z-bend ties in accordance with the present invention. 
       FIG. 6  is a front sectional view of the ICF with Z-bend ties in accordance with the present invention. 
       FIG. 7  is a perspective view of the Z-bend tie in accordance with the present invention supported on a gauge. 
       FIG. 8  is a side sectional view of a reinforcing section bent over a crosstie element in a Z-bend tie in accordance with the present invention. 
       FIG. 9  is a top plan view of 8 inch Z-bend ties nested in accordance with the present invention. 
       FIG. 10  is a top plan view of 6 inch Z-bend ties nested in accordance with the present invention. 
       FIG. 11A  is a top plan view of Z-bend ties nesting in a pallet in accordance with the present invention 
       FIG. 11  is a top plan view of a pallet of nested Z-bend ties in accordance with the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   With reference to  FIGS. 4-6 , a tie  24  in accordance with the present invention, for an ICF  20  consisting of walls or slabs of EPS foam  22 , is illustrated. According to one aspect of the present invention, the tie  24  comprises a first planar section  32 , a second planar section  33 , a third planar section  35 , and a fourth planar section  37 . The first planar section  32  is formed of intersecting elements  28  and  30  and has a first side  40 , a second side  38 , a first end  34 , and a second end  36 . The second planar section  33  is connected to the first side  40  of the first planar section  32  at approximately a right angle. The third planar section  35  is connected to the second side  38  of the first planar section  32  at an angle greater than 90 degrees. The fourth planar section  37  is connected to the third planar section  35  at an angle less than 90 degrees. 
   In one embodiment, shown in  FIGS. 4 and 6 , a first furring strip  50  extends across and is connected to the second planar section  33  of the tie  24 . Likewise, a second furring strip  52  may extend across and be connected to the third planar section  35  and the fourth planar section  37  of the tie  24 . In another embodiment, the second furring strip  52  may only extend across and be connected to the fourth planar section  37  of the tie. The first furring strip  50  and the second furring strip  52  function as anchor strips into which screws or other fasteners may be inserted to hold finish materials such as drywall or siding on the outside of the walls  22 . 
   According to another aspect of the present invention, the tie  24  comprises at least one crosstie element  28  and at least one reinforcing element  30 . Each crosstie element  28  has a first side section  44 , a central section  42 , and a second side section  45 . The first side section  44  is connected to the central section  42  at approximately a right angle. The second side section  45  comprises a first portion  46  connected to the central section  42  at an angle greater than 90 degrees, and a second portion  48  connected to the first portion  46  at an angle less than 90 degrees. Each reinforcing element  30  is connected to the central section  42  of at least one crosstie element  28 . 
   In one embodiment, shown in  FIGS. 4 and 6 , a first furring strip  50  extends across and is connected to the first side section  44  of the tie  24 . Likewise, a second furring strip  52  may extend across and be connected to the second side section  45  of the tie  24 . In another embodiment, the second furring strip  52  may only extend across and be connected to the second portion  48  of the second side section  45  of the tie. The first furring strip  50  and the second furring strip  52  function as anchor strips into which screws or other fasteners may be inserted to hold finish materials such as drywall or siding on the outside of the walls  22 . 
   The ties  24 , when used in connection with the walls  22  of the ICF  20 , function in the same manner as the conventional U-shaped ties  14 , shown in the prior art  FIGS. 1-3 , or as the conventional H-shaped ties. Moreover, because the second planar section  33 , the third planar section  35 , and the fourth planar section  37  (or, in another aspect of the present invention, the first side section  44  and the second side section  45  of the crosstie elements  28 ) are encapsulated within the EPS walls  22  ( FIGS. 5 and 6 ), the end user is unable to identify that the tie  24  of the present invention is used instead of the conventional U-shaped or H-shaped tie of the prior art. 
   In one embodiment of the present invention, the tie  24  is constructed by bending the tie  24  from a flat configuration into the Z-shaped ties  24  of the present invention. In another embodiment, the tie  24  may be constructed of formed metal. In a still other embodiment, the tie  24  may be constructed of injection molded plastic. 
   With reference to  FIG. 7 , the tie  24  is shown on a gauge  80 . The gauge  80  is used for quality control purposes and may be constructed of aluminum, steel, or any dimensionally stable material. 
   With reference to  FIGS. 4 and 8 , in one embodiment of the present invention, the tie  24  is constructed by bending the reinforcing element  30  over the central section  42  of the crosstie element  28 . The reinforcing element  30  may be connected to the crosstie element  28  by spot welding or any other suitable means. 
   Importantly, the Z-bend ties  24  in accordance with the present invention may be nested to form a stack  60 , as shown in  FIGS. 9 and 10 . Shipping the Z-bend ties  24  in a nested stack  60  produces lower transport costs as compared to the conventional U-shaped and H-shaped ties which are not nestable. Consequently, the Z-bend ties  24  can be made and formed at one factory and shipped worldwide for use at multiple EPS molding plants. 
   In certain embodiments, ties  24  of the present invention may range in size (width×length) from 7 in.×12 in. to 12 in.×21 in. The first side section  44  and the second side section  45  of each crosstie element  28  may each extend about 1.5 in. from the center section  42  of the crosstie element  42 . Ties  24  may range in weight from approximately 0.5 lbs to 1.2 lbs depending upon area of the first planar section  32 . The average weight per planar square foot for such ties  24  is approximately 0.75 lbs per square foot. 
   With continuing reference to  FIGS. 9 and 10 , ties  24  within the range outlined above are stacked one on top of the other. As shown, a first tie  24   a  in accordance with the present invention is adapted to receive a like second tie  24   b  for nesting more than one tie in a stack  60 . In particular, each crosstie element  28   a  of the first tie  24   a  is adapted to receive each like crosstie element  28   b  of the second tie  24   b . The second side sections  45  of the crosstie elements  28  are adapted to overlap each other as the ties  24  are shifted back-and-forth (into and out of the page of  FIGS. 9 and 10 ) by the thickness of the crosstie element  28 . 
   In one embodiment, as shown in  FIG. 9 , an 8 in. tie  24  (8 in. is the length C of the center section  42  of the crosstie element  28 ) has a bend angle A of approximately 135 degrees between the center section  42  of the crosstie element  28  and the first portion  46  of the second side section  45  of the crosstie element  28 . In another embodiment, as shown in  FIG. 10 , a 6 in. tie  24  (6 in. is the length D of the center section  42  of the crosstie element  28 ) has a bend angle B of approximately 120 degrees between the center section  42  of the crosstie element  28  and the first portion  46  of the second side section  45  of the crosstie element  28 . 
   With reference to  FIG. 11   a , ties  24  in accordance with the present invention are shown nesting in a pallet  90 . Specifically,  FIG. 1  la shows that a second side section  45   a  of a crosstie element  28   a  of a first tie  24   a  is adapted to receive a like second side section  45   b  of a like crosstie element  28   b  of a second tie  24   b  for nesting the first tie  24   a  and the second tie  24   b .  FIG. 11  shows the arrangement of four different nested stacks  60  on a pallet  90 . 
   Pallets  90  of ties  24  may be organized for transport in 40 ft. containers. A typical 40 ft. container has a useable interior volume of about 2,500 cubic feet and a net weight capacity of 40,000 lbs of product. This size and capacity equate to a density of 16 lbs per cubic foot of packaged product, if every square inch of space in the container is used. Allowing for pallets  90 , other dunnage, and some maneuverability space to load and unload the container, an actual product density of about 20 lbs per cubic foot is desired to achieve a practical utilization of the container&#39;s weight capacity and cubic volume capacity simultaneously. 
   Therefore, in order to achieve the target density of about 20 lbs per cubic foot of product, the ties  24  must nest within the stack  60  to a pitch, or spacing, of 27 layers of ties per foot of depth (27 layers per foot×0.75 lbs per square foot per layer=20 lbs per cubic foot density). This stack configuration equates to an average spacing of ties  24  (from bottom most surface of one tie to the bottom most surface of the next) of about 0.44 in. 
   In one embodiment, the tie  24  is constructed of two layers of 3.0 mm wire and one layer of 0.7 mm sheet metal, giving a total construction thickness of about 0.27 in. To achieve the pitch of 0.44 in., the space between nested parts must be 0.17 in. or less. Similar calculations must be undertaken if molded plastic ties are substituted for the wire ties  14 . 
   Therefore, in order to achieve the target density of 20 lbs per cubic foot of product, the conventional ties  14  must nest to a pitch, or spacing, of 27 layers of ties  14  per foot of depth (27 layers×0.75 lbs per square foot per layer=20 lbs per cubic foot density). This configuration equates to an average spacing of ties  14  (from bottom most surface of one tie  14  to the bottom most surface of the next tie  14 ) of 0.44 in. 
   The conventional tie  14  is constructed of two layers of 3.0 mm wire and one layer of 0.7 mm sheet metal, giving a total construction thickness of about 0.27 in. To achieve the pitch of 0.44 in., the space between nested parts must be 0.17 in. or less. Similar calculations must be undertaken if molded plastic ties are substituted for the wire ties  24 . 
   While this invention has been described with reference to preferred embodiments thereof, it is to be understood that variations and modifications can be affected within the spirit and scope of the invention as described herein and as described in the appended claims.