CLAMP FOR INTERCONNECTING COMPONENTS OF CONCRETE FORMING

APPARATUS BackRTound of the Invention

This application claims priority to United States Patent Application Serial No. 60/662,075, filed March 15, 2005.

1. Field of the Invention

The invention relates generally to concrete forming apparatus used in forming concrete structures and, more specifically, to a clamp, useful in interconnecting form panels of concrete forming apparatus, which includes a fixed jaw that carries a centering pin and a moveable jaw that receives the centering pin that is moved to and held in a clamping position by a tapered pin or wedge.

2. B ackground of the Prior Art Concrete forming apparatus is in wide use in the construction of buildings, bridges, and other concrete structures. A common system for forming concrete structures uses a plurality of modular form components that are adapted to be assembled into a wide variety of configurations to conform to virtually any architectural requirement. Such forming apparatus components are typically made of metal so that they are strong enough to support the heavy weight of poured concrete and durable so that the components can be reused many times.

One of the most commonly used configurations of such metal form components is a form panel that is used in forming substantially flat or curvilinear concrete surfaces, such as walls, foundations, pillars, and the like. Such metal concrete form panels have a face sheet which is in contact with the concrete being poured. A rearwardly extended flange is secured around the perimeter of the face sheet. A plurality of spaced apart stiffeners or ribs are tied to the perimeter flanges of the form panel on the opposite side of the face sheet from the wall or other structure being formed.

Because of the variety in the size and shape of concrete structures formed using the form panel, it is advantageous to have the ability to interconnect the various components of the form panel in a wide variety of configurations without unduly multiplying the number of distinct components that are required to assemble the form

panel of the desired diversity. Accordingly, a number of attempts have been made to design clamps or couplings for interconnecting components of form panel that are adjustable to fit a wide variety of configurations.

One such coupling is described in the United States Patent No. 5,713,687. The patent describes a coupling for interconnecting a horizontal panel at any desired position along a pair of vertical shoring posts. The coupling has a mouth formed of a stationary and moveable jaw. The moveable jaw is closed towards the stationary jaw by driving behind the moveable jaw a wedge-shaped tensioning member. The coupling mouth, when tensioned by the wedge, engages the vertical shoring post at the desired position. In an alternative embodiment, the wedge includes ribs that run at an angle with respect to the longitudinal axis of the wedge and which engage teeth on the moveable jaw to move it between an opened position and a clamped or tensioned position.

Another such coupling device is described in United States Patent No. 6,322,277 ^' . A clamp for interconnecting two components of a support apparatus such as components of a shoring apparatus for concrete foaming systems is disclosed. A clamp member having swing arm jaw is received for pivotal movement in a housing that is secured to one of the components. A plurality of flutes disposed at an angle to the pivot axis of the clamp member are received in coacting recesses in the housing. Axial movement of the clamp member pivots the swing arm and a coacting, moveable jaw toward a fixed jaw formed in the housing to releasably secure the clamp to the other component. The jaws of the clamp are designed to engage mating surfaces of a post used to support shoring apparatus.

United State Patent No. 4,881,716 describes a formwork lock for clamping two formwork panels together. Adjacent panels are assembled side-by-side with perimeter flange portions in contact engagement. The formwork lock has a pair of jaw members that are slideably moveable relative to each other between an open position where the perimeter flanges are received inside the jaws and a clamped position where the lock holds the perimeter flanges together. A wedge is used to hold the jaws in the clamped position.

Summary of the Invention

The invention consists of a clamp for releasably securing to each other a pair of form panels of a concrete forming apparatus. The clamp includes a pair of jaws that pivot relative to each other about a common pivot axis between a closed or clamping position, a partially open or undamped position, and a fully open position. The first or fixed jaw has a pair of spaced-apart ear members, each of which has an opening centered on the common pivot axis. The second or pivoting jaw has a single ear member which also has an opening. The single ear member of the pivoting jaw is received inside the spaced-apart ears of the fixed jaw with the openings aligned. A wedge-shaped pin is received in the aligned openings with the longitudinal axis of the pin coincident with the pivot axis of the jaws. Movement of the wedge along its longitudinal axis will move the pivoting jaw between the undamped position and the clamped position. Each of the end surfaces of the wedge has an impact surface which may be struck by a hammer or the like to bring the jaws to the clamped position or to release the jaws from the clamped position.

As the jaws move toward the clamped position, the clamping end portions of the jaws opposite the opening approach each other. An aligning pin projects from the clamping end portion of the fixed jaw and in the direction of travel of the fixed jaw toward the clamped position. There is provided a receiving opening in the clamping end portion of the pivoting jaw that receives the aligning pin as the pivoting jaw moves toward the clamped position. An object of the present invention is to provide a clamp for interconnecting form panels of a concrete forming apparatus that is quickly and easily moveable between a released and a clamped position.

Another object of the present invention is to provide a clamp for interconnecting form panels of a concrete forming apparatus which is durable and provides the requisite strength while being economical to manufacture.

These and other objects of the invention will be made apparent to a person that is skilled in the art upon a review and understanding of this specification, the associated drawings, and the appended claims.

Brief Description of the Drawings

Fig. 1 is a perspective view of the clamp of the present invention in the closed position.

Fig. 2 is a perspective view of the clamp of the present invention in the open position. Fig. 3 is a detailed view of the fixed jaw of the clamp of the present invention.

Fig. 4 is a detailed view of the clamp of the present invention shown in the clamped position and the open position, including a pair of form panels of the forming apparatus. Fig. 5 is a detailed view of the pivoting jaw of the clamp of the present invention. Fig. 6 is a detailed view of the wedge of the clamp of the present invention. Detailed Description of Preferred Embodiments

In the art of using formwork in the building of concrete structures, wet or plastic concrete is poured inside an assembly of formwork. The formwork is comprised of flat panels, panels that can be pre-formed to assume a curvilinear shape, forms that have a predetermined, fixed curvilinear shape, corner forms, and a variety of other forms for both general and specific applications such as are known in the art. These forms have a face sheet or the like against which the plastic concrete is poured and which, accordingly, determines the contour of the final concrete structure in the area of the form, hi many instances, the individual forms are placed adjacent other forms and are held in place by clamps, fasteners, connectors, walers, shoring posts, and the like. By combining the variety of forms into a formwork assembly, virtually any desired shape of building structure can be formed.

Plastic concrete is a heavy fluid that can exert very large forces on the formwork until the concrete has sufficiently cured. Accordingly, it is critical that the shoring and other support apparatus used to hold the forms in place be sufficiently strong to resist the forces of the plastic concrete. This has become of even greater importance in recent years with the increased use of modern concrete formulations which have a lower viscosity and allow higher heads of plastic concrete to be used in the formwork. It is also important that proper registry of the forms is achieved during initial assembly of the formwork and maintained throughout the pouring of concrete inside the formwork.

Customarily, a plurality of form panels are used to form part of a concrete structure. The panels are arranged so that face sheets of the panels define the surface of the concrete

structure being formed. Often, it is desired that the finished concrete structure be smooth and uniform, relatively free of form marks or the like that may result in the area of transition from one form to the adjacent form. The likelihood of such undesirable markings is reduced or eliminated if the forms are designed and manufactured to close tolerances and then assembled and held in place with the face sheets of adjacent panels in contact engagement along the length of the adjacent edges of the forms and the adjacent forms are oriented so that there is a smooth transition from one face sheet to the next. In the particular example of form panels having planar face sheets, a smooth transition is achieved if the face sheets are coplanar upon assembly, hi another example wherein a cylindrical column is being formed using forms having a predetermined, fixed and constant radius of curvature, a smooth transition is achieved if the adjacent forms are oriented so that their shared radius of curvature defines a common central longitudinal axis. In the example of a planar form panel and a form of fixed curvature being used adjacent to each other, a smooth transition is achieved if the plane of the form panel is coincident with the tangent of the fixed curvature form along the adjacent edge. As seen in Figure 4, the form panels 12 are held in place most typically be attaching the shoring and other support apparatus to the perimeter flanges 16a, 16b or the reinforcing ribs (not pictured) or both. In the present invention, a clamp 20 is used to assist in proper registry of the form panels 12 during assembly and to hold the form panels 12 in the desired orientation and registry while the concrete is being poured and cured. In Figures 1-6, the form clamp 20 is used to connect individual form panels 12 into larger assemblies. The clamp 20 has a fixed jaw 22, a pivoting jaw 24, and a tapered pin or wedge 26. When the wedge 26 is driven into the closed position, the wedge 26 brings the fixed jaw 22 and the pivoting jaw 24 together and aligns the panels together using the holes in the panels. The fixed jaw 22 has a clamping end portion 28 and a pivot axis or wedge- receiving end portion 30. The end portion 30 includes a pair of parallel, spaced-apart ear members 32 and 34 forming a channel therebetween, each of which has a slot-shaped opening 36 and 38, respectively. The pivoting jaw 24 has a clamping end portion 40 and a wedge-receiving end portion 42 which has an slot-shaped opening 44. Upon assembly, the end portion 42 of the pivoting jaw 24 is positioned inside the ear members 32 and 34 of the fixed jaw 22 with the opening 44 put into substantial coaxial alignment with the openings 36

and 38. The wedge 26 is inserted into the aligned openings 44, 36, and 38. The wedge 26 has a closing end 58 and an opening end 60, which may include a button-strike surface 61. (Fig. 6). The pivoting jaw 24 is accordingly mounted on the fixed jaw 22 for pivotable and translatable movement relative thereto, moving the clamping end portion 40 of the pivoting j aw 24 toward and away from the clamping end portion 28 of the fixed jaw.

An aligning pin or tooth 46 projects from the clamping end portion 28 of the fixed jaw 22 in the direction of travel toward the pivoting jaw 24. (Fig. 3). A corresponding opening 48 is formed in the clamping end portion 40 of the pivoting jaw 24. (Fig. 5). As the pivoting jaw 24 is moved toward the fixed jaw 22, the tooth 46 will be received in the opening 48.

As seen in Figures 2 and 4, the wedge 26 allows for two different types of motion between the fixed jaw 22 and the pivoting jaw 24. When the wedge 26 is in the open position (see Fig. 2), the pivoting jaw 24 can translate and pivot outward and away from the fixed jaw 22. The pivoting jaw 24 includes three stops 70, 72, and 74 to limit the range of motion of the pivoting j aw 24. In the open position, pivoting j aw 24 moves translatably away from the fixed jaw 22. Once stop 70 on the pivoting jaw 24 has cleared the fixed jaw 22, the pivoting jaw 24 can then rotate, which allows the clamp 20 to release the forms. Jm the open position, stops 72 and 74 limit the rotation of the pivoting jaw 24. In the closed position, stops 70, 72, and 74 limit the rotation of the pivoting jaw 24. In Figure 4, each form panel 12 has perimeter flanges 16a and 16b that include a plurality of corresponding openings 19 that, when a pair, of form panels are oriented side-by- side with their face sheets in a coplanar relationship, are in coaxial alignment with the corresponding openings in the adjacent perimeter flange of the other panel. In use of the clamp 20, a pair of form panels 12 are brought into closely adjacent positions with their face panels roughly parallel to and in alignment with each other. The clamp 20 is put into its fully open condition and positioned so that the tooth 46 in the fixed jaw 22 is at least roughly aligned with one of the openings in a first one of the panels along the adjacent perimeter flange 16. The pivoting jaw 24 is pivoted toward the fixed jaw 22, bringing the tooth 46 into the corresponding opening of the second one of the panels 12. The wedge 26 is then moved in a direction to pivot the pivoting jaw 24 to the clamped position. The tooth 46 causes the

corresponding openings in the two panels are brought into coaxial alignment. Use of two or more clamps 20 on the adjacent perimeter flanges 16 will ensure that the face sheets 14a and 14b of the two form panels 12a and 12b will be substantially coplanar.

To secure the clamp 20 and the form panels 12, a hammer or similar tool is used to impact the closing end 58 of the pin 26, wedging the pin 26 in the openings 36, 38, and 40 so that it will not be accidentally dislodged during use of the assembled form panels 12 in constructing a formwork assembly or during pouring and curing concrete in the formwork assembly. The clamp 20 can be easily released by impacting the opening end 60 of the pin 26 with a hammer or similar tool. In the preferred embodiment, the fixed jaw 22, pivoting jaw 24, and wedge 26 are made of investment cast steel. These parts may also be manufactured using alternate methods, including forging.

Although the invention has been described with respect to a preferred embodiment thereof, it is to be also understood that it is not to be so limited since changes and modifications can be made therein which are within the full intended scope of this invention as defined by the appended claims.