HK1153247B - Expandable ceiling grid - Google Patents

Description

Expandable ceiling grid

Technical Field

The present invention relates to improvements in suspended ceiling grid structures.

Background

Suspended ceilings typically comprise a rectangular metal grid that supports rectangular tiles. These grid elements are typically suspended from overhead structures by spaced-apart suspension wires and most commonly have an inverted "T" shaped cross-sectional shape. The tiles are removably laid over the flanges of the tees. More specifically, the grid is typically constructed in a "strip" form, with main tees first suspended and cross tees thereafter assembled individually on the main tees. Skilled installers have developed a number of different techniques and methods to reduce the time required to build a ceiling grid. The need to individually manipulate, align, and insert tees into slots of the main tees has been an obstacle to further reducing the amount of labor used to build the grid considerably.

Disclosure of Invention

The present invention provides factory-assembled grid modules for suspended ceilings that can significantly reduce the amount of labor required to build a grid. A module includes a plurality of main tees and a set of complementary cross tees. According to the invention, the cross tees are hinged at their ends to the main tees at regularly spaced locations along the main tees. The module can be stocked and transported in a limited volume collapsed configuration in which the tees are all aligned directly adjacent to each other in the same or substantially the same direction.

The module is expanded when it is built by simply swinging the cross tees relative to the main tees at their hinged ends. In one embodiment of the present disclosure, the hinge joints are arranged to allow the cross tees to fold over the main tees with their flanges overlying the flanges of the main tees to advantageously reduce the perimeter of the collapsed module. Still further, the disclosed hinge structure has an indexing or positioning feature that biases the expanded grid into a square expanded configuration.

Drawings

Fig. 1A, 1B, 1C, and 1D are schematic plan views of the progression of a grid module from a fully collapsed state to a fully expanded state. Each representing a sequential phase;

FIG. 2 is a plan view of a section of the cross tees and main tees and contact areas of the module in a folded or collapsed condition;

FIG. 3 is a cross-sectional elevation view of the grid module in a folded state;

FIG. 3A is a fragmentary, cross-sectional view similar to FIG. 3, but on an enlarged scale;

FIG. 4 is a perspective view of a main tee and cross tee junction area showing the cross tee in a most prominent position in a collapsed condition; and is

Fig. 5 is a perspective view of a junction area between a main tee and opposing cross tees in their unfolded or expanded positions.

Detailed Description

The present invention is illustrated diagrammatically in fig. 1A-1D, wherein a folded grid assembly or module 10 (fig. 1A) is progressively unfolded or expanded to a fully deployed or expanded configuration (fig. 1D). The grid module 10 includes a plurality of relatively long main tees 11 (typically 10 feet in length) and a plurality of shorter cross tees 12 (typically two feet in length). Metric equivalent lengths may be used for the main or cross tees. The cross-sections of the illustrated tees 11, 12 are conventional, with a horizontal lower flange 13 extending laterally symmetrically on both sides of the lower edge of a vertically extending plane of a web 14. A hollow reinforcing bulb 16 extends transversely symmetrically along the top of the web 14. Typically, the tees 11, 12 are roll formed from sheet steel as is known in the art.

The ends of the cross tees 12 are hinged to the main tees 11 at regularly spaced locations along the length of the main tees 11. The locations along the main tees 11 correspond to conventional locations and in the illustrated example are on a two foot center or metric equivalent length. In the example shown, the module 10 includes five main tees 11 and 25 cross tees 12.

When the module 10 is in its expanded mounted state, the same bracket 21 is centered and secured to the main tees 11 at the location of the corresponding points at which the extended centerlines of the cross tees 12 intersect the main tees at right angles. The illustrated bracket 21 is used to attach one end of a separate cross tee 12 on each side of the main tee 11 to which it is mounted. The bracket 21 of the illustrated version may be die cast from a suitable metal or molded from a suitable flame retardant plastic. The bracket 21 has a central body having an inverted U-shaped cross section transverse to its longitudinal direction. A slot 23 of the body 22 is complementary to the cross-sectional shape of the main tee 11 in the region of its bulbous portion 16, so that it can be snapped onto the tee or slid lengthwise from the end of the tee to a desired position, thereby giving the body a saddle-like relationship with the tee. The bracket 21 may be secured in place on the tee 11 by screws, rivets, or similar fasteners assembled in a plurality of holes 24. Straddling the tee 11 on each of a pair of opposed legs 26, the bracket 21 includes a complete lateral extension 27 near its lower edge. Each extension 27 has a proportional vertical counterbore 28 to receive a vertical shoulder bolt 29 which operates as a hinge pin forming a pivot center with its longitudinal axis spaced from the central plane or web 14 of the respective main tee 11. Each end of a cross tee 12 is fitted with a hinged joint bracket 31. Like the main tee bracket 21, the cross tee bracket 31 may be die cast from metal or molded from a suitable plastic. The cross tee bracket 31 has an inverted U-shaped portion 32 which is assembled, saddle-shaped, over the cross tee bulb 16 and over the upper region of the web 14. The bracket 31 is secured to the cross tee 12 by screws or other fasteners positioned in a plurality of holes 33. The bracket 31 includes a connecting arm 34 that extends upwardly and longitudinally from the U-shaped saddle portion 32. The arm 34 has a vertical through bore 36 having a diameter substantially the same as or slightly larger than the major diameter of the main tee bracket extension counterbore 28. The axis of the hole 36 lies in the plane of the web 14 of the cross tee 12. The shoulder bolt 29 is assembled in the bracket holes 28, 36 to connect the associated end of a cross tee 12 to a main tee 11. The shoulder of the bolt 29 abuts the bottom of the counterbore 28 in the extension 27 and the bolt is secured in place by a nut 37. The bolt 29 has a column length long enough to carry a compression spring 38 between its head 39 and the top surface of the connecting arm 34.

The mating surfaces 41, 42 and arms 27, 34 of the primary and secondary tee bracket extensions have complementary crown configurations that provide a detent action that releasably locks the secondary tee 12 in either a stowed position (generally aligned with the associated main tee 11) or an extended position (where it is at right angles to the main tee). This locating action includes rounded downward projections 43 on the opposite side of the bore 36 on the lower face of the cross tee bracket arms 34 that fit into rounded notches 46, 47 on the upper face of the main tee extension 27. The shallower notch 46 corresponds to the collapsed position of the cross tee, while the deeper notch 47 corresponds to the expanded position. The compression spring 38 biases the cross tee projection 43 into the notches 46, 47 to releasably maintain the cross tee in a collapsed or expanded position. Preferably in this collapsed position, the cross tee 12 is held parallel to the main tee 11 to which it is connected, as is the case with all other main tees and cross tees. The positioning of all these projections 43 serves to keep the grid module 10 square in the expanded or expanded position. Preferably, the brackets 21, 31 are proportioned to hold the cross tee flanges 13 slightly above and out of contact with the flanges 13 of the main tees 11 when the projections 43 rest in the shallow recesses 46, as shown in fig. 3A.

Referring back to fig. 1A-1D, the grid module 10 appears as a package in a collapsed or folded state, which by way of example is 143 "x 7.25" x 2 "(11.92 ' x 0.61 ' x 0.17 '). When the module is fully expanded, it may cover an area of 10 'x 10'. It should be observed that substantially no effort is expended in assembling the cross tees 12 to the main tees 11 within the module 10 on site, thereby providing considerable speed in installation. The invention is particularly suited for use in large areas where the modules 10 can be quickly joined together along their edges and a limited number of cross tee ends attached to the sequential modules.

Although the present invention has been disclosed with respect to grids having 2 'x 2' sections, it should be understood that other conventional arrangements, such as 2 'x 4', or 2-1/2 'x 5' arrangements, may be produced by the present invention. These dimensions may be adapted to metric equivalents.

While the invention has been shown and described with respect to a particular embodiment thereof, this is for the purpose of illustration rather than limitation, and other variations and modifications of the particular embodiments herein shown and described will be apparent to those skilled in the art and all are within the intended spirit and scope of the invention. Therefore, this patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention.

Claims (10)

1. A preassembled suspended ceiling grid module comprising a plurality of parallel main tees and a plurality of cross tees, the main and cross tees each have horizontal flanges extending to both sides of a central plane, the cross tees are joined at their ends to the main tees by end connectors, the end connectors enable the module to be folded in a zig-zag pattern in a plane corresponding to a final ceiling plane, such that the cross tees lie in a direction parallel to the main tees such that the cross tees connected on one side of a particular main tee are folded in a common direction relative to their end connectors and where connected to an adjacent main tee are folded in an opposite direction relative to their end connectors of said adjacent main tee.

2. A preassembled suspended ceiling grid module as set forth in claim 1, wherein each of said end connections provides a hinge center spaced from the central plane of its corresponding main tee.

3. A preassembled suspended ceiling grid module as set forth in claim 2, wherein each hinge center is spaced from the central plane of the corresponding main tee by a distance at least equal to one-half of the flange width of a cross tee.

4. A preassembled suspended ceiling grid module as set forth in claim 1, wherein each of said end connections allows the flanges of its associated cross tee to overlie the flanges of the main tees to which the end connection is connected and overlie the flanges of adjacent main tees connected on opposite ends of the associated cross tee.

5. A preassembled suspended ceiling grid module as set forth in claim 1, wherein said end connection includes a spring action to bias its associated cross tee to a deployed position in which the cross tee is at a right angle to the associated main tee.

6. A preassembled suspended ceiling grid module as set forth in claim 1, wherein said end connection includes a spring action to bias its associated cross tee to a folded position in which the cross tee is parallel with the associated main tee.

7. A preassembled suspended ceiling grid module as set forth in claim 1, wherein said end connection includes a vertical hinge pin.

8. A preassembled suspended ceiling grid module as set forth in claim 1, wherein the cross tees connected on the outside of an outer one of said main tees do not have a main tee attached at their distal ends.

9. A preassembled suspended ceiling grid module as set forth in claim 1, wherein said end connections include mating brackets on the main tees and on the cross tees.

10. A preassembled grid for a suspended ceiling comprising a plurality of main tees and sets of cross tees, the main and cross tees each including a central vertical web and a lower horizontal flange extending on either side of the web, the cross tees being connected to the main tees at spaced intervals along the main tees in a manner that enables the cross tees to be folded toward the main tees and the main tees to be spaced in parallel relationship at a spacing between adjacent main tees that is substantially less than the length of the cross tees.