Patent Application
20180291622
This disclosure relates generally to the field of beams that are roll-formed from sheet metal and that comprise the grid of suspended ceilings and, more specifically, beams with a bulb that contains at least one reinforcing pleat, which increases the structural load capacity of the beam.
Relatively light roll-formed sheet metal beams currently used to comprise the grid of a suspended ceilings are shown, for instance, in U.S. Pat. Nos. 5,979,055 and 6,138,416. Typically, such light beams are arranged into a grid, as shown, for instance, in U.S. Pat. No. 6,763,642. The grid supports panels, which provide a pleasing cover over a room, with minimal use of metal in the grid beam. This minimization of metal also minimizes the structural load capacity of the beam. As a result, although the beams are not typically subjected to additional structural loads, when the beams are subjected to an additional structural load the load is a light-weight load, such as the loads shown in U.S. Pat. No. 3,612,461 (a light fixture), or U.S. Pat. No. 4,073,458 (an advertising sign).
Where it is necessary to support heavier structural loads, such as data banks, from a suspended ceiling, heavy forged metal beams are typically incorporated into the ceiling grid in place of the light roll-formed sheet metal beams described above. The incorporation of forged metal beams increases costs and installation times as the forged metal beams contain more material than the roll-formed beams and the installer must switch back and forth between the installation of two types of beams.
Therefore, there exists a need for a roll-forged beam with increased load capacity, which does not use significantly more material.
To meet this and other needs, and in view of its purposes, a roll-formed steel beam with a bulb that contains at least one pleat is provided. In one embodiment, this pleated bulb increases structural load capacity by over twenty percent (20%), while only using about twelve percent (12%) more material then prior designs. Furthermore, this beam can be installed in the same manner as prior roll-formed beams.
The disclosed beam is comprised of: (1) a web having a top and a bottom edge opposite each other; (2) two flanges opposite each other at the bottom edge that each extend out in a substantially perpendicular angle from the web; and (3) a bulb, which contains at least one pleat, at the top of the web. Typically, the pleat will be on the top of the bulb so as to provide the greatest increase to the load capacity.
The beam may also be incorporated into a ceiling system to form a suspended support grid which includes a plurality of intersecting grid support members arranged horizontally with grid openings formed between the grid support members. The suspended ceiling grid formed from the beams is suspended from a structural support, such as a structural ceiling, by hang wires.
In one embodiment, threaded load and hang rods are secured to a suspended ceiling grid formed from the disclosed beam by clips shaped to transmit loads in a substantially vertical manner through the webs of the beams while minimizing the twisting and/or bending of the beams. The load and hang clips are spaced on the suspended ceiling at locations that maintain a level and balanced suspended ceiling. Lower threaded load rods may be secured to the beams with load clips in a manner that passes the loads vertically upward through the webs of the beams to grid beam hang clips, at selected ceiling locations on the grid, above the suspended ceiling. The grid beam hang clips receive and pass the load through the suspended ceiling to upper threaded rods, above the suspended ceiling, that are secured into the upper structural support, again, such as a support ceiling.
A method for forming the beams is provided. The method includes providing flat coil stock that is fed into a series of rollers which: (1) draws the stock to the centerline to form a pleat; (2) flattens the pleat; (3) applies a zigzag to each half of the stock to form the bottom of the bulb and the top edge of the web; (4) bends the edge of each side of the stock approximately ninety degrees (90°) to produce a flange; (5) folds the stock down the centerline; and (6) stitches the web together forming the beam.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention.
The invention is best understood from the following detailed description when read in connection with the accompanying drawing and appended claims. It is emphasized that, according to common practice, the various features of the drawing are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawing are the following figures:
The features and benefits of the disclosed beam are illustrated and described by reference to exemplary embodiments. The disclosure also includes the drawing, in which like reference numbers refer to like elements throughout the various figures that comprise the drawing. This description of exemplary embodiments is intended to be read in connection with the accompanying drawing, which is to be considered part of the entire written description. Accordingly, the disclosure expressly should not be limited to such exemplary embodiments illustrating some possible non-limiting combination of features that may exist alone or in other combinations of features.
In the description of embodiments, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top,” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be construed or operated in a particular orientation. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” and similar terms, refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both moveable or rigid attachments or relationships, unless expressly described otherwise.
Beam Structure
Bulb
In simple loading conditions, the bulb 130 of the beam 100 is the weakest link. When the face of the beam 100 (i.e., the bottom edge 112 with the flanges 120) is under tension it typically will not fail under load tests. When the bulb 130, however, is under compression it may buckle (i.e., fail), which causes grid collapse. Increasing the beam height to gain loading capacity is not desirable due to installation constraints. Increasing the gauge of the material, “wastes” the material in areas that do not need increased performance (i.e., the bottom edge 112 and web 110). The pleat 132 at the top of the beam 100 is the most efficient way to increase the load capacity of the beam 100 while not wasting material. Here, the bulb 130 may also have multiple pleats 132. For example, in
Web
In
Flanges
To provide additional structural support, and as illustrated in
Beam Manufacture
Beam Materials
It will be understood that the beam 100 may be constructed out of any bendable material such as metals, polymers, or carbon fiber. Preferably, the beam 100 is manufactured from metal. More preferably, the beam 100 is manufactured from rolled steel.
Beam Dimensions
The height of the beam 100 is between approximately 1 inch (2.54 cm) to 6 inches (15.24 cm). More preferably, the height of the beam 100 is between approximately 1.50 inches (3.81 cm) to 1.75 inches (4.45 cm). Most preferably, the height of the beam 100 is between approximately 1.65 inches (4.19 cm) and 1.70 inches (4.32 cm).
The flange width of the beam 100 is between approximately 0.5 inches (1.27 cm) and 4.00 inches (10.16 cm). More preferably, the flange width of the beam is between approximately 0.56 (1.42 cm) and 0.94 inches (2.39 cm). It will be further understood that the inclusion a cap 410 may further increase the width of the flanges 120 of the beam 100.
The material gauge from which the beam 100 may be constructed may be between approximately 0.008 inches (0.020 cm) and 0.05 inches (0.127 cm). More preferably, the material gauge may be between approximately 0.01 (0.025 cm) and 0.018 inches (0.046 cm).
Incorporation into a Ceiling System
The disclosed beam 100 may be incorporated into a ceiling system grid framework to increase the load capacity of the ceiling system. This first requires the formation of a grid framework with tessellation (i.e., a pattern of flat shapes with no overlaps or gaps). The tessellations may be a regular tessellation (i.e., repeating regular polygons such as triangles, squares, rectangles, hexagons, etc.) or semi-regular tessellations (i.e., a grid made of two or more regular polygons such as hexagons/triangles, triangles/squares, hexagons/squares/triangles, octagons/squares, etc.).
The grid is suspended from a structural support, such as a structural ceiling, by hang wires or hang rods located above the grid of beams 100. Panels may also be placed in the grid openings.
The grid can be adapted to transmit relatively heavy loads from below the suspended ceiling to structural supports above the suspended ceiling. A skilled artisan would further understand that heavy loads are those loads such as data banks attached to the suspended ceiling, whereas light loads may be considered most light fixtures attached to the suspended ceiling.
To increase the load capacity of the suspended ceiling, and therefore the ability of the suspended ceiling to support heavy loads, threaded load and hang rods may be secured to the suspended ceiling grid by clips shaped to transmit loads vertically through the webs of the beam 100, without twisting or bending the beam 100 in the grid. Examples of such clips are disclosed in U.S. Pat. No. 9,255,402, incorporated in this document by reference.
The load and hang clips may be further spaced on the suspended ceiling at locations that maintain the level and balance of the suspended ceiling, notwithstanding the heavy loads that are being supported through the suspended ceiling by the clips and the threaded rods secured to the clips. In one embodiment, the suspended ceiling may remain balanced, level, and intact even though the load below the grid of beams 100 is not spread evenly over the grid of beams.
In this configuration, relatively heavy loads may be suspended from the grid without the need to incorporate heavy forged metal beams into the grid. The heavy loads may be secured to the beam 100 by lower threaded load rods secured to the beam 100 with grid beam load clips, preferably attached to the face of the beam 100. These clips may be secured in a manner that passes the loads in a vertical or approximately vertical manner upward through the web 110 of the beam 100 to the hang clips and then from there up through to the structural support. In one embodiment, the load clips and/or the hang clips grip the beams 100 without weakening the beams 100.
In this way, the load hung below the suspended ceiling passes upwardly through the web of the beam, without twisting or bending the beam. The grid beam clips above the ceiling are preferably spaced on the web 110 to balance the load from the grid beam load clips below the ceiling, and may be further designed to avoid twisting or bending of the beam 100.
Structural Load Tests
The pleat 132 at the top of the disclosed beam 100 is the most efficient way to increase load capacity of the beam 100. Indeed, the inclusion of the pleat 132 increases load capacity by over twenty percent (20%) while only increasing material usage by approximately 11-12%.
Two vertical load failure tests were conducted on a rolled steel beam with the design similar to the beam design disclosed in U.S. Pat. No. 6,138,416 (i.e., a beam with a bulb that does not contain a pleat). Specifically, the tests were conducted on a non-pleated bulb with a length of forty-eight inches, with a single stitch in the web, a height of 1.670 inches, a flange width of 0.558 inches and a material gauges of 0.01 inches (0.026 cm), and 0.015 inches (0.038 cm). During the tests, weight was applied to the center. The results of the failure tests are disclosed below in Table 1:
Eight vertical load failure tests were conducted on a rolled steel beam 100 with a structure as disclosed in
The results of the three vertical load failure tests on Beam A are outlined in Table 2 below where deflection is measured in inches (cm):
The result of the two failure tests on Beam B are outlined in Table 4 below where deflection is measured in inches (cm):
The results of the three failure tests on Beam C are outlined in Table 5 below where deflection is measured in inches (cm):
As can be seen, the inclusion of the pleat 132 increased the load capacity of the beam 100 while at the same time minimizing the requirements for the incorporation of additional material (i.e., minimizing costs).
Although illustrated and described above with reference to certain specific embodiments and examples, the present invention is nevertheless not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the spirit of the invention. It is expressly intended, for example, that all ranges broadly recited in this document include within their scope all narrower ranges which fall within the broader ranges. It is also expressly intended that the steps of the methods of using the various devices disclosed above are not restricted to any particular order.
This application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 62/482,726, filed on Apr. 7, 2017, the contents of which are incorporated in this application by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62482726 | Apr 2017 | US |
