The present invention relates to reinforcing bars (“rebars”) used in construction, and more particularly to providing a support chair for elongated bars used during construction.
Concrete is commonly used as a construction material because of its relatively low cost. Concrete is very strong in compression, but weak in tension. To increase the tensile strength of concrete, steel reinforcement bars (“rebars”) are added. For foundations, road work or other flat constructions, the rebar is often laid out in a grid pattern beneath the surface of the construction. To hold the rebar together in a grid, the bars are tied together where they intersect.
Various codes specify where the rebar must be placed. For example, the American Concrete Institute (ACI) in Section 318 of their code specifies that the rebar in a slab-on-grade foundation must be placed at the midpoint depth of the foundation. Thus, for example, in a four inch foundation slab, the rebar grid would normally be placed at a depth of approximately two inches. Consequently, the grid must be elevated off the ground to the desired position before concrete is poured. In many cases, concrete laborers use stones, pieces of broken bricks or materials to elevate the grid. This can cause the grid to be uneven or sag when the concrete is poured.
For concrete pillars and beams, the rebar is tied to a set of wooden frames and placed in a mold. The concrete is then poured into the mold to form the pillar, beam or other construction. However, this method suffers many disadvantages. First, it is difficult to align the rebar in parallel around the frames. Second, the frames often break or shift when the concrete is poured, causing the rebar to become misaligned. This reduces the tensile strength of the construction.
In one embodiment of the present invention, a chair for supporting one or more bars comprises a base, where the base is configured to provide stability to support the chair. The chair further comprises legs coupled to the ends of the base. Additionally, the chair comprises a lateral cross member spanning between the legs, where the lateral cross member comprises one or more receptacles to receive a reinforcing bar, where each of the one or more receptacles comprises a set of sidewalls defining an opening to receive and retain the reinforcing bar. The set of sidewalls spread apart laterally so that the opening can widen to receive the reinforcing bar, where the opening closes to have a width less than that of the reinforcing bar when the reinforcing bar is in a retaining area.
The foregoing has outlined rather generally the features and technical advantages of one or more embodiments of the present invention in order that the detailed description of the present invention that follows may be better understood. Additional features and advantages of the present invention will be described hereinafter which may form the subject of the claims of the present invention.
A better understanding of the present invention can be obtained when the following detailed description is considered in conjunction with the following drawings, in which:
Embodiments described herein provide a support chair for elongated bars used during construction including, but not limited to, rebar, plumbing, tubing, electrical conduit and other elongated bars. While the following examples will be discussed primarily in the context of rebar, it should be understood that embodiments of the present application can be used for other purposes.
Base 102 can have any desired form factor including that of a ring, a solid plate or other form factor. Base 102 can be sized to provide sufficient stability to support chair 100 so that support chair 100 does not topple during expected loads experienced during construction.
Lateral cross-member 104 spans between legs 106. Lateral cross-member 104 includes bar receptacles 108 open to the top side of lateral cross-member 104 and sized to receive the rebar. Lateral cross-member 104 can be formed from a resilient plastic or other material so that rebar receptacles 108 form a snap-fit. Adjacent openings can be separated by arms 109.
Legs 106 can have any desired configuration and height and can include a single leg or additional legs to support lateral cross-member 104. According to one embodiment, a single leg that spans the width of chair 100 and is integrated with lateral-cross member 104 can be used. In other embodiments, other suitable supports and bases can be used to support lateral cross-member 104
In the embodiment of
Bar retaining area 114 can be open to the top of lateral cross-member 104 (e.g., opening 110) and area 116 (e.g., opening 118). The width of opening 110 can be less than the width of rod retaining area 114. The opening 110 can be shaped so that, as a bar enters opening 110, the bar pushes sidewalls 112 apart to widen opening 110. When the bar enters area 114, opening 110 can close to have a width that is less than that of the bar to retain the bar. The bar can rest on shoulders 115. Receptacle 108 can act as a snap-fit using the spring action of lateral cross-member 104 to close opening 110 and provide feedback to a user.
In the embodiment of
In the embodiment of
According to one embodiment, the outer portion of legs 106, the outer portion of lateral-cross member 104 and sidewalls 112 can be formed from a continuous rib of material 122. Additional material 124 extending from rib 122 can provide additional structural support. According to one embodiment, material 124 can be thinner than rib 122 and be shaped to allow flexibility of arms 109. By way of example, but not limitation, material 124 can shaped so that arms 109 have a bow-like shape.
While, in the embodiments discussed above, support chair 100 is aligned to support a horizontal rebar, support chair 100 can also be used in the construction of walls and be arranged to support a vertical rebar. Additionally, chair 100 can be used to support other bars including, but not limited to, plumbing, conduit, tubing or other elongated rod used in construction.
Thus, embodiments described herein can comprise a chair for supporting one or more bars. The chair can include a base, a lateral cross member and a support to support the lateral cross-member a distance away from the base. The lateral cross member can include one or more receptacles to receive the bar. Each receptacle can have a set of sidewalls defining an opening open to a side of the lateral cross member (e.g., the top side). The lateral cross-member can be configured to allow the sidewalls to spread apart laterally so that the opening can widen to receive a bar. The lateral-cross member can be formed of a resilient material so that the opening closes to have a width less than that of the bar when the bar is in the bar retaining area. The lateral cross-member can include multiple bar receptacles to retain parallel bars. The bar receptacles, according to one embodiment, can act as snap-fits.
As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, product, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
Additionally, any examples or illustrations given herein are not to be regarded in any way as restrictions on, limits to, or express definitions of, any term or terms with which they are utilized. Instead these examples or illustrations are to be regarded as being described with respect to one particular embodiment and as illustrative only. Those of ordinary skill in the art will appreciate that any term or terms with which these examples or illustrations are utilized encompass other embodiments as well as implementations and adaptations thereof which may or may not be given therewith or elsewhere in the specification and all such embodiments are intended to be included within the scope of that term or terms. Language designating such non-limiting examples and illustrations includes, but is not limited to: “for example,” “for instance,” “e.g.,” “in one embodiment,” and the like.
Further modifications and alternative embodiments of various aspects of the disclosure will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the disclosure. It is to be understood that the forms of the disclosure shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the disclosure may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the disclosure. Any dimensions provided are provided by way of example only and not limitation. Changes may be made in the elements described herein without departing from the spirit and scope of the disclosure.
This application is related to the following commonly owned co-pending U.S. patent application: Provisional Application Ser. No. 61/309,785, “Rebar Support Chair,” filed Mar. 2, 2010, and claims the benefit of its earlier filing date under 35 U.S.C. §119(e).
Number | Date | Country | |
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61309785 | Mar 2010 | US |