Abstract:
A re-usable form for making diamond isolation joints used in the construction of buildings is disclosed. The form is made from wood, plastic cardboard, plastic sheet, wax coated cardboard or other material that can easily be separated from concrete. The form is placed onto a footing for a column or block out and the floor is poured around the form. After the floor is cured the form is collapsed inside itself to create the void of the diamond isolation joint. The form can be re-used in another isolation joint in the same building or on future construction projects. The form can be fabricated on site in various heights and dimensions. The form is folded or collapsed to make it easier to transport and store.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to a concrete form for making isolation joints in building construction. More particularly, the concrete form is fabricated to allow it to be easily assembled into place, the concrete is poured around the form and the form is removed and available for use in another location. The form is collapsible allowing it to fold upon itself allowing for easier transportation and storage.  
       BACKGROUND OF THE INVENTION  
       [0002]     The construction or forming of diamond isolation joints today is most commonly performed by constructing a wooden form over the footing of a support column or block out. The form is then filled with sand and the floor is poured around and on top of the form. After the concrete is hardened the concrete is removed from the top of the form, the sand is removed from inside the form and the wooden form is destructively removed from the cavity. Because the form is fabricated from solid pieces of wood it must be discarded when removed. There is waste in both the time it takes to construct, set and fill the form as well as the time it takes to remove and destroy the form to clear it from the cavity. Some patents and patent applications have been filed and issued to try and improve the construction of isolation joints.  
         [0003]     U.S. Pat. No. 5,224,313 issued Jul. 6, 1993 and Published application US2004/0045241 published Mar. 11, 2004, both by Otis P. Guillebeau disclose a form that is mounted to the pad for a roof support column or block out. While the form provides an isolation diamond shape to support a roof column or block out, the form is cast and left in the floor of the building. Leaving the form in the floor of the building is not acceptable for building code in some areas. Since the form remains in the floor the form is also not re-usable.  
         [0004]     U.S. Pat. No. 6,513,291 issued Feb. 4, 2003 to Gilsdorf discloses a conical form for making an isolation slab for a building support column or block out. While this patent discloses an isolation form for a building column or block out the form does not make a diamond joint, and the form is cast into the concrete where it remains after the floor slab has been poured. Leaving the form in the floor of the building is not acceptable for building code in some areas. Since the form remains in the floor the form is also not re-usable.  
         [0005]     U.S. Pat. No. 5,857,302 issued Jan. 12, 1999 to Lill discloses members that provide concrete crack control. The members are cast into and or beneath the floor of the concrete slab and provide an expansion mechanism to reduce potential cracking of the floor in a location other than the expansion or saw cut lines. While this patent discloses an isolation form for a building column or block out the form does not make a diamond joint, and the form is cast into the concrete where it remains after the floor slab has been poured. Leaving the form in the floor of the building is not acceptable for building code in some areas. Since the form remains in the floor the form is also not re-usable.  
         [0006]     U.S. Pat. No. 4,830,543 issued May 16, 1989 to Joubert discloses a foundation support for a building. The support form is a pyramid or cone shaped component that is placed on top of a column or block out foundation and the floor is poured onto and around the form. While this patent discloses an isolation form for a building column or block out the form does not make a diamond joint, and the form is cast into the concrete where it remains after the floor slab has been poured. Leaving the form in the floor of the building is not acceptable for building code in some areas. Since the form remains in the floor the form is also not re-usable.  
         [0007]     What is needed is a re-usable form for making diamond isolation joints. The proposed application satisfies this need by providing a form for making isolation joints that are removable from the surrounding floor and can then be re-used in another location or stored for future use.  
       BRIEF SUMMARY OF THE INVENTION  
       [0008]     It is an object of the re-usable isolation joint to provide a form that is used to make an isolation joint and then removed from the floor and used in future locations, this provides the benefits of easier construction of the forms as well as elimination of the waste that is present when wooden forms are constructed and then destructively removed from the floor slab.  
         [0009]     It is an object of the re-usable isolation joint to provide an isolation joint that is diamond, square, rectangular, round, pentagonal, octagonal, or other shape based upon the building code or architectural requirements.  
         [0010]     It is another object of the re-usable isolation joint to provide a form that can be manufactured at the work site to accommodate design requirements. The form is manufacturable to various heights and sizes using tools that are available at the job site.  
         [0011]     It is another object of the re-usable isolation joint to provide a form that is foldable for a smaller storage and or transportation size. This provides a tremendous benefit over other systems that are a fixed size and contain mostly an air cavity.  
         [0012]     It is another object of the re-usable isolation joint to provide a form that is made from plastic cardboard, wax coated cardboard or other material that resists bonding with concrete. This material is easily cut and formed at the job site to provide the form for the isolation joint.  
         [0013]     It is another object of the re-usable isolation joint to provide a form that is made from a rigid material that is hinged to allow it to be opened to form the isolation pocket, and also hinged to pull the form away from the surrounding floor after the floor is set.  
         [0014]     It is another object of the re-usable isolation joint to provide a re-usable cover for the isolation joint pocket that allows the cavity to be covered and reduce intrusion of concrete into the interior of the isolation pocket form.  
         [0015]     It is another object of the re-usable isolation joint to provide a block out to control irregular cracking around the column or block out.  
         [0016]     It is still another object of the re-usable isolation joint to provide a form that is collapsible into itself to make removal of the form from the surrounding floor easier.  
         [0017]     Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]      FIG. 1  shows an isometric view of a building construction site showing where the isolation form is used.  
         [0019]      FIG. 2  shows an isometric cross sectional view of the form for an isolation joint.  
         [0020]      FIG. 3  shows a hinged form that forms the isolation joint pocket.  
         [0021]      FIG. 4  shows a semi-rigid form that forms the isolation joint pocket.  
         [0022]      FIGS. 5   a - 5   d  shows the steps involved in using the isolation joint form.  
     
    
     DETAILED DESCRIPTION  
       [0023]     Referring to  FIG. 1  that shows an isometric view of a building construction site showing where the isolation form is used. This figure shows a typical floor  100  with a wall section  110  installed on one side of the floor. Columns  140  are shown inside of the diamond isolation joint pocket  150 . The columns  140  support the roof structure or any upper floor sections (not shown). Because of the weight that exists in the roof or upper floors a footing must be poured under the columns to support the weight. The description of the footing and the use of the form for the diamond isolation joint are described in more detail with  FIGS. 2-5 . Typically the footings that exist under the floor  100  are excavated and poured prior to pouring the floor slab. Due to the separate footing pour under the floor as well as the need for expansion and movement, the concrete at the support columns is poured separately from the footing and the floor, so it can move semi-independently from the floor. The expansion joint is also constructed with expansion joints  120  that connect each of the isolation pockets as well as the ends of the slab. The expansion joints  120  are typically spaced about 30 feet apart. The concrete is also typically saw-cut  130  at intervals between the 30 foot joints at 10 to 15 foot intervals  130 . The saw cut lines provide pre-defined crack/ expansion locations for the concrete sections to expand and or move. After the floor is formed the wall  110  is poured and lifted or built into position. The wall can include one or more door openings  112  and one or more window openings  114 .  
         [0024]     Referring to  FIG. 2  that shows an isometric cross sectional view of the form for an isolation joint. The form  10  is shown here placed on top of footing  155  that is poured into the excavation hole  160 . The footing hole is dug and spaced in accordance with the building plans, structural requirements and building code. The footing  155  is poured into hole  160  that is dug into the ground  165  and the footing is poured to a depth that places the top of the footing below the surrounding ground. The footing  155  typically includes rebar pieces  170  that increase the tensile strength of the concrete  155 . Anchors  180  are typically placed into and or around the rebar members  170 . The anchors provide a mounting for the columns as shown in  FIG. 1 . A space or holding plate  190  keeps the anchors in place while the concrete footing  155  hardens to ensure that the anchors are in the correct position and orientation after the concrete footing hardens or sets. The form  10  is located atop the footing prior to pouring the floor. The construction of the form  10  is shown and described in more detail in  FIG. 3  and another contemplated embodiment is shown and described in  FIG. 4 . Additional description of using the form is described in  FIG. 5 .  
         [0025]     In the preferred embodiment the isolation joint form is in the shape of a diamond, but other shapes are contemplated including but not limited to round, triangular, square, rectangular, trapezoidal, parallelogram, pentagonal, hexagonal or polygonal. The dimensions of the diamond isolation joint are usually specified in the design plans of the building and the outside dimensions are usually 24, 30 or 36 inches across but other dimensions and configurations are contemplated. The height of the diamond isolation joint is also specified in the plans for the building but is typically 6 to 24 inches in height. When the diamond isolation joint form is used the top of the form is typically placed about  2  inches below the top of the finished floor height.  
         [0026]     Referring to  FIG. 3  that shows a hinged form that forms the isolation joint pocket. In this preferred embodiment the form is constructed from a plastic, wood, pressed wood or manufactured wood that is not significantly affected by water or concrete. Each side  20  of the form  10  is made from two pieces that are hinged  90  in the center. The center hinge(s) allow the sides  22  of the form to be collapsed inward to pull them away from the poured and set concrete that is poured around the form. Hinge(s)  30  are placed on the corners of the form that operate with the center hinges  90  to collapse the form into the concrete poured around the isolation joint. Hardware such as screws or other similar fastening means  32  secure the hinges to the form. When the sides of the form are straightened a rod  40  is placed through “U” clips  42  that keep the sides of the form in an essentially straight configuration. The rods maintain the sides straight as the concrete is poured around the form and pushed in on the sides of the form. Another typical method of maintaining the sides of the form in a straight condition is fill the inside of the form with an expendable material such as sand or other material that is removed from the inside of the form after concrete is poured around the form. Hardware such as screws  44  or other similar fastening means secure the “U” clips to the form. In another contemplated embodiment the rods are replaced with latched, clasps or clamp the pull on the opposing sides of the center hinge(s)  90  to maintain the sides of the form in a straight orientation.  
         [0027]     With all the rods removed the form can be folded in upon itself to form a flat shape that can be easily transported and stored. Because the form folds in upon itself it is not destroyed upon removal from the surrounding concrete floor. After storage or transportation the form can be re-used to make future or subsequent isolation joint pockets.  
         [0028]     Referring to  FIG. 4  that shows a semi-rigid form that forms the isolation joint pocket. This preferred embodiment of the isolation joint form  50  is constructed from a pliable material where the walls can be flexed towards the inside of the isolation pocket to remove the form from the surrounding concrete. The form is preferably made from plastic cardboard or wax coated cardboard but other equivalent materials are contemplated that do not bond with the concrete or degrade from contact with water or concrete. In the preferred embodiment the form  50  is constructed from a sheet of material that is cut to the desired height and folded to make the diamond shape. In the preferred embodiment the isolation joint form is in the shape of a diamond, but other shapes are contemplated including but not limited to round, triangular, square, rectangular, trapezoidal, parallelogram, pentagonal, hexagonal or polygonal. The walls in the preferred embodiment are straight and perpendicular, but it is further contemplated that the side walls can be angled inward or outward creating a draft angle to more easily allow the form to be removed from the concrete poured and set around the form.  
         [0029]     The dimensions of the diamond isolation joint are usually specified in the design plans of the building and the outside dimensions are usually 24, 30 or 36 inches across but other dimensions and configurations are contemplated. The height of the diamond isolation joint is also usually specified in the plans for the building but is typically 6 to 24 inches in height. When the diamond isolation joint form is used the top of the form is typically placed about 2 inches below the top of the finished floor height. A standard 4 foot by 8 foot sheet of material will yield four 10 inch high forms that are 23½ inches on each side.  
         [0030]     The end flap  65  of the diamond isolation form wrapped over one side  60  of the form. Plastic or metal strapping material  70  is wrapped around the form to keep the form in a diamond shape. A clasp  75  or similar connecting mechanism holds the ends of the strap together. Corner protectors  72  reduce the possibility that the strap  70  will crush the corners and more evenly distributes the load of the strap  70  on the corners of the form. If the form is tall, more than one strap is used with the form. In one contemplated method of using the form, the form is filled with expendable material such as sand that is removed from within the form prior to removal of the form from the concrete poured around the form. In another contemplated embodiment a cap  80  is placed inside the form to maintain the shape of the form and eliminate the need for the sand. The cap  80  has holes or other features  82  to allow the cover to be removed from the form after the concrete has been poured and set around the form. The form is typically placed 2 inches below the finished grade, and the height of the cap is constructed such that the upper lip of the cap accommodates the 2 inches of depth. After the concrete is sufficiently cured and the sand or cap is removed the sides of the pliable form are bent inward to pull it away from the concrete and remove it from the pocket. The form is then folded transported stored and/or re-used to construct another diamond isolation pocket.  
         [0031]     Referring to  FIGS. 5   a - 5   d  that show the steps involved in using the isolation joint form. In  FIG. 5   a  hole(s)  160  are dug in the ground to accommodate the column or block out footing. The rebar material  170  is placed within the hole. The rebar is usually placed on rebar Dobie or other spacers to keep the rebar from being cast on the dirt. The bottom of the hole may also be covered with a layer of sand or other material. Concrete is poured into the footing and threaded anchors are usually set and cast into the footing as shown in  FIG. 2 . After the concrete in the footing is sufficiently set the form  10  is placed on top of the footing as shown in  FIG. 5   b.    
         [0032]     The footing is usually set several inches into the hole  160  below the surrounding ground. A locating spacer plate  190  maintains the location of the anchors  180  in the footing.  FIG. 5   c  shows the isolation diamond joint form  10  in the hole  160 , with sand  82  filling the inside of the form. At this stage the concrete floor can be poured around and on top of the form  10 .  
         [0033]     After the concrete floor  100  is poured the concrete over the form is broken away, the sand or other expendable material  82  is removed from within the form, and the form is collapsed into the center of the pocket for removal, transportation, storage or to be used to form another isolation joint. The locating spacer plate  190  maintains the location of the anchors  180  in the footing. A future pour of concrete fills the void with or without the column attached to the threaded ends of the anchors.  
         [0034]     In the embodiment including the cap  80  as shown and described in  FIG. 4 , the pocket is not filled with expendable material  82 , and the cap is removed providing an open pocket where removal of the form is simplified.  
         [0035]     With all the rods removed the form can be folded upon itself to form a flat shape that can be easily transported and stored. Because the form folds in upon itself it is not destroyed upon removal from the surrounding concrete floor. After storage or transportation the form can be re-used to make future or subsequent isolation joints.  
         [0036]     Thus, specific embodiments of a re-usable form for making isolation joints have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims.