The present invention relates to web inserts for I-joists. More particularly, the present invention relates to web inserts for supporting tubing, piping, cables and the like commonly installed across web holes of wooden I-joists in architectural constructions.
I-joists referred in the following and in the context with the present invention are made from wood and wood like materials. I-joists become increasingly popular in architectural construction due to their high load carrying capability and their low weight, as well as their inexpensive fabrication and their good workability. I-joist's high gravitational load carrying capability is provided by a large height to width ratio with a thinned central web portion connecting the top and bottom chord. Top and bottom chords are mainly exposed to tensile or compressive loads in grain direction of naturally grown wood, whereas the web has to withstand tensile, compressive and shear loads in varying combination. Because of the webs' diverse load exposure and its relatively large height, webs are commonly fabricated from omni directionally laminated veneers or wood fiber patches. The I-joist is a multi material structural element with two sets of materials of quite diverse composition and physical properties bonded together along the interfaces between top and bottom chords and their respective central webs.
Maintaining the structural integrity of the bonding interface between web and chords is crucial for the I-joist's load carrying capability. I-joist manufacturers provide therefore standards for maximum web hole sizes and minimum remaining intact web structure height along the bonding interface. A practicable fabrication of web holes in accordance with such web hole standards is provided by a web hole cutting apparatus, the patent for which is incorporated by reference. Irrespective a proper cutting, the web hole may still suffer damage during the consecutive installation of pipes, tubes, and cabling at the construction site. Particularly sensitive is the bottom portion of the web hole due to its exposure to the gravitational loads of the through guided elements. Therefore, there exists a need for a structural element protecting the web hole against damage during installation and/or gravitational loads of piping, tubing, cabling and the like guided through that web hole. The present invention addresses this need.
In an installed I-joist, web area is limited for cutting web holes. As a common result, a multitude of pipes, tubes and/or cables tend to be cramped through a single web hole. The resulting friction between the individual through guided elements may cause excessive lateral loads on the web, which in turn may increase the I-joist's buckling risk at the already weakened web hole location. Therefore, there exists a need for a structural element that keeps individual through guided elements separated and spaced within a single web hole. The present invention addresses also this need.
An I-joist having a standardized hole cut in the vertical web portion between its top and bottom chord may be combined with an insert correspondingly shaped to the dimensional standards of the I-joist and the cut hole. The insert provides clustered cutout contours for positioning and holding various through guided elements such as tubing, piping, cables and the like commonly installed across I-joists in architectural constructions. The insert may be snapped on the I-joist, screwed on, nailed on, attached with a countering thread ring and/or in combination with an I-joist support. The insert may be preferably fabricated from plastic
The insert is an easy to handle and easy installable element that in combination with standardized cut web holes provides guiding and support across I-joists in accordance with specialized needs of plumbers, electricians and the like.
An I-joist 10, a portion of which is depicted in the Figures, may be combined with an insert 20A-20F in various configurations and eventual combination with other structures, such as attachment pins 30 as in
According to
Inserts 20A-20F may feature cutout contours 25 in varying configurations and spacing as may best accommodate the particular needs for installing tubes, pipes, wiring and the like through guided elements commonly employed in architectural constructions. The cutout contours 25 are densely arrayed to provide support and positioning for such through guided elements in tight clusters. At the same time, the cutout contours 25 provide spacing preferably in compliance with well known building codes and the like.
In the example of insert 20A, the cutout contours 25 are substantially square except peripheral cutout contours 25 limited by the surrounding fit ring 28 as shown in
The fit ring 28 is adjacent the flange 21 and may comply with its outside contour to the hole diameter HD of the standardized web hole 14 for positioning the insert 20A-20F within the web hole 14. Such web hole 14 may be cut into the web 13 via a specialized tool that cuts the hole with diameter HD and with a predetermined chord offset OF from at least one but preferably both of top chord 12 and bottom chord 11. Such specialized tool may one as described in the cross referenced patent titled “I-joist Hole Cutting Apparatus”. Hole diameter HD and chord offset OF are preferably predetermined in accordance with well known static and other safety criteria well known for I-joists employed in architectural constructions.
The inserts 20A-20F are preferably dimensioned in accordance with standardized hole diameter HD and chord offset OF for an I-joist 10 of a dimensional standard characterized also by web height WH. For example, at the time of the present invention was made, there exist dimensional standards in the United States for web heights WH of at least between 4.5″ and 13.0″ with 0.5″ increment. Corresponding hole diameters HD may be about 0.5″ or 0.75″ in diameter smaller than the web heights WH making the standardized offsets OF about 0.25″ and 0.375″.
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The present invention includes embodiments, in which the fit ring 28 is other than circular. Referring to
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The I-joist support 50 may feature attachment holes and a chord rest 54 for a rigid interconnection between I-joist support 50 and I-joist 10 such that load carrying capacity and/or buckling resistance of the I-joist 10 is improved.
Gravitational load transfer may be provided from a load rest 27 of the insert 20F onto a correspondingly shaped central contour 51 of the I-joist support 50. In case of a U-shaped support 50, the load rest 27 may correspond to a central arc of the central contour 51 as illustrated in
For example, a thread ring 40A may be shaped in correspondence to the central contour 51 and/or to the cord rest 54 such that gravitational load may be transmitted from the insert 20D via the thread ring 40A onto the I-joist support 50. In that case, merely the ring 40A may be provided in different configuration to provide combined and exclusive utilization of insert 20D and I-joist support 50.
Inserts 20A-20F are preferably monolithically fabricated from plastic. Thread flange 40A, 40B may be fabricated from plastic or sheet metal. I-joist support 50 may be fabricated preferably from sheet metal.
Accordingly, the invention described in the specification above is set forth by the following claims and their legal equivalent:
The present invention claims priority to U.S. Provisional Application of the same title and inventor, Application No. 60/552,326, filed Mar. 10, 2004, which is hereby incorporated by reference. The present invention cross references and incorporates by reference U.S. Pat. No. 6,857,831, filed Feb. 27, 2004, titled “I-joist Hole Cutting Apparatus” and U.S. application Ser. No. 10/410,505, filed Apr. 8, 2003, titled “Buckling Opposing Support for I-joist”, both of the same inventor as in the present application.
| Number | Date | Country | |
|---|---|---|---|
| 60552326 | Mar 2004 | US |