Patent Application
20080128581
The present invention generally relates to a radius forming system for forming flatwork concrete and cement structures, such as sidewalks, roads, and similar constructions.
Concrete forming systems have been in use for a long time, and include various types of structures, including those made of wood and those made of metal. While wood and metal forms are generally used for forming straight sections, oftentimes it is necessary to form curved sections, with various sized radii. Metal forms are available for forming some curved sections, such as disclosed in U.S. Pat. Nos. 965,979, 2,846,748, and 5,154,837 as are wooden forms, however, generally only very large radii can be formed with such forms.
In order to form curves having a smaller radius, special forms must be constructed, usually of materials that can be used only a single time, such as Masonite®, plywood and “bender board” and often require significant labor to be employed in constructing the form, putting it in place and subsequently removing it.
Plastic forms have been provided for concrete forming systems, to take the place of metal or wood forms. Such forms have various structural features to enhance the rigidity of the forms, to compensate for their reduced rigidity, as compared to metal or wood forms, yet allow the reduced weight and reusability for the forms. Various plastic or flexible forms are disclosed in U.S. Pat. Nos. 4,579,312, 4,712,764, 4,750,703, 4,776,555, 6,021,994, 6,629,681 and 6,866,239.
Plastic forms are well suited for forming curves, however, because of the structural features incorporated into the plastic forms to enhance their rigidity, such forms are useful for forming curves generally where the radius is no less than about 3 feet. Difficulty still arises in trying to construct concrete shapes with radii of less than about 3 feet.
The present invention provides a radius forming system for forming concrete with curves having a radius of less than 3 feet, and down to about 6 inches. The radius forming system includes at least one flexible form member and a plurality of stake pockets. The stake pockets are each formed in a single piece having a first end with a first opening therethrough arranged to receive a fastening element and a second end with a second opening therethrough spaced a first distance from the first opening and arranged to receive a fastening element and an intermediate portion having an enclosing shape defining a stake holder. The intermediate portion has at least one opening therethrough and a locking member is received in the opening arranged to engage a stake positioned in the stake holder.
The form member is formed of a single thickness and has a plurality of first openings and second openings vertically aligned and spaced along the length of the form member, spaced from each other by the first distance and each opening is arranged to receive a fastening element. A plurality of fastening elements are received in the various openings in the form member and the stake pockets to hold the form member and stake pockets together.
In an embodiment, the radius forming system has a plurality of form members, and a form connector is provided for connecting adjacent form members. In such an embodiment, the form members have a third opening and a fourth opening vertically aligned and spaced a second distance from each other and a third distance from the first end of the form member and each opening is arranged to receive a fastening element. The form connector is formed of a single flat plate having a having a third opening and a fourth opening vertically spaced from each other by the second distance and spaced from an edge of the plate by a fourth distance greater than the third distance and arranged to receive fastening elements. The fastening elements are also used to hold the form member and end connector together. Adjacent forms are abutted end to end, and the form connector attached to the first end of one form will overlie a portion of the second end of the next form to prevent the end of the second form from moving relative to the first form.
In an embodiment, the stake pocket is formed of metal.
In an embodiment, the end connector is formed of metal.
In an embodiment, the intermediate portion has at least a partial circular shape defining the stake holder.
In an embodiment, the intermediate portion has a full circular shape.
In an embodiment, the opening through the intermediate portion is threaded.
In an embodiment, the threaded opening comprises a threaded nut secured to the stake pocket.
In an embodiment, the locking member comprises a threaded locking pin with an end arranged to engage a stake positioned in the stake holder.
In an embodiment, the locking pin has a knob shaped handle, and in another embodiment, the locking pin is formed in an L shape.
In an embodiment, the fastening elements comprise threaded bolts.
In an embodiment, the flexible form member is made of a plastic material.
In an embodiment, the plastic material is polyethylene.
In an embodiment, the thickness of the flexible form member is between 0.125 and 0.50 inches.
In an embodiment, the height of the flexible form member is between 3 and 12 inches.
In an embodiment, the length of the flexible form member is between 6 and 15 feet.
In an embodiment, between 1 and 12 stake pockets are provided for each flexible form member.
While the present invention may be embodied in many different forms, there is shown in the drawings and discussed herein one or more specific embodiments of a radius forming system 20 for forming concrete. The system 20 as shown in place in
The stake pockets 24 (different embodiments being shown in
The intermediate portion 38 has at least one opening 40 therethrough, and a locking member 42 is received in the opening arranged to engage a stake 44 positioned in the stake holder 38. In an embodiment, the opening 40 is threaded, as at 46, and in some configurations, the threaded opening may be formed by a threaded nut 48 secured to the intermediate portion 38, such as by welding. The threaded nut 48, if used, would overlie an opening 50 in the intermediate portion 38 which may or may not be threaded. In an embodiment where the opening 40 is threaded, the locking member 42 may comprise a threaded locking pin 52 with an end 54 arranged to engage the stake 44 positioned in the stake holder 24. The locking pin 52 may be provided with a knob 55 (
In other embodiments, the opening 40 in the intermediate portion 38 may be two spaced apart openings, and the locking member 42 could be a wedge shaped member, such as disclosed in U.S. Pat. No. 6,629,681, incorporated herein by reference.
The size and configuration of the enclosing shape of the intermediate portion 38 should be selected to accommodate various sized stakes 44, 44′ commonly used, such as 0.75 inch and 0.875 inch diameter stakes.
The form member 22 has a plurality of first openings 58 and second openings 60 which may be vertically aligned and spaced along the length of the form member. The first and second openings 58, 60 are spaced from each other by the first distance 36 and each is arranged to receive a fastening element 30. The openings 58, 60 should be arranged to align with the openings 28, 34 in the stake pockets 24 and to match whatever number and arrangement is used for the stake pocket openings. An advantage of using two openings vertically aligned is that the flexibility of the form member 22 along its length is not restricted as it would be if the openings were spaced longitudinally along the form member for each stake pocket 24. A number of openings 58, 60 can be preformed in the form member 22 to allow the selection and placement of the appropriate number of stake pockets 24 required for a particular installation. For example, between 1 and 12 pairs of openings 58, 60 can be preformed in the form member 22, or additional pairs, depending on the length of the form member. Of course, additional openings 58, 60 can be provided in the field when necessary for a particular installation. Where the desired radius to be formed by the form member 22 is smaller, the number of stake pockets 24 used for each given length of the form member may need to be increased, so that the form member is supported to maintain the proper curvature of the desired radius.
A plurality of the fastening elements 30 are received in the various openings in the form member 22 and the stake pockets 24 to hold the form member and stake pockets together. In an embodiment, the fastening elements 30 may comprise bolts with heads 62 that are rounded or are recessed in the form member 22, so as to leave a minimal to non-existent indentation in the formed concrete which is to be poured on the fastener head side 63 of the form member 22 and nuts 65 engaging a threaded portion of the fastening element on an opposite side 67 of the form member.
In an embodiment, the radius forming system 20 has a plurality of form members 22, and a form connector 64 is provided for connecting adjacent form members. In such an embodiment, the flexible form members 22 may be arranged in series with a first end 66 of one flexible form member abutting a second end 68 of the next flexible form member.
To accommodate the form connector 64, the form members 22 have a third opening 68 and a fourth opening 70 which may be vertically aligned and spaced a second distance 72 from each other and a third distance 74 from the first end 66 of the form member and each arranged to receive a fastening element 30. The form connector 64 may be formed of a single flat plate 76, preferably made of a rigid material, such as metal or a suitable rigid plastic, having a having a third opening 78 and a fourth opening 80 vertically spaced from each other by the second distance 72 and spaced from an edge 82 of the plate by a fourth distance 84 greater than the third distance 74 and arranged to receive fastening elements 30. The form connector 64 may alternatively be formed of two flat plates 76 that sandwich the form member 22 therebetween at the first end 66. Fastening elements 30 are also used to hold the form member 22 and form connector 64 together.
The form connector 64 has a portion 86 which extends longitudinally beyond the first end 66 of the form member 22, which will overlie the second end 68 of the adjacent form member. Although no separate fasteners are required between the second end 68 of the adjacent form member 22 and the extending portion 86, the extending portion will provide a rigid backing and support for the second end, especially once the concrete is poured and is pressing against the form members. When the form connector 64 is formed of two flat plates, the second end 68 of the adjacent form member 22 is captured between the two plates, and is held in place. The plates 76 are thin enough that even when a second plate is used on the concrete side of the form, the impression it leaves in the formed concrete is nearly invisible. Toe-nailing and other creative splicing procedures that are labor-intensive and damage the forms at the end joints are eliminated with the use of the form connector 64.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.
