Abstract:
Suspended ceiling grid runners include a flange extending laterally to both sides, the flange forming a three dimensional face including sides visible from below a plane of the grid, opposed cross runners intersecting through runners with their ends joined by mutually interlocking end connectors extending through a slot in the through runner, the cross runner ends including end edges configured to abut a respective side of the flange of the through runner, a connector when connected to an opposite connector causes the associated end edges to resiliently locally deflect the abutted flange side to substantially eliminate any gap therebetween.

Description:
The invention relates to suspended ceiling components and, in particular, to a novel grid runner construction. 
     PRIOR ART 
     Conventional suspended ceilings comprise elongated metal runners arranged in the form of a rectangular grid and rectangular panels or tiles carried on the grid to close the spaces outlined by the intersecting grid elements. The ceiling is suspended from above by suspension wires. In most cases, the grid elements have faces visible from below the ceiling. Architects and interior designers continuously look for grid face designs that are more distinctive than the flat face that is most commonly used in the building industry. 
     When a grid face is three dimensional, it can be difficult to construct a miter or faux miter joint between intersecting grid runners that is not prone to show a visually objectionable gap or gaps at the joint. 
     SUMMARY OF THE INVENTION 
     The invention comprises suspended ceiling grid runners with a three dimensional face flange. The grid runner lends itself to forming essentially gapless faux miter joints without requiring a high skill or extra time expenditure on the part of the installer. The disclosed grid runner profile has a V-shaped face that can resiliently deflect to a limited extent to precisely conform to the cut edges of intersecting cross runners. 
     The longitudinal location of end connectors on the cross runners is arranged so that when a pair of opposed connectors are locked together in a slot of the through runner, they produce a slight interference fit against the face flange of the through runner they intersect. This fit slightly resiliently squeezes the V-shaped face flange laterally inward thereby eliminating any readily perceptible gap. Thus, the invention obtains a very neat faux miter joint requiring nothing more than a stab-in connection of the cross runners. No particular skill, dexterity or precision alignment is necessary, and the joint is effected in as much time as it takes to align a cross runner connector with a receiving slot in the through runner and pushing it through the slot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a fragmentary perspective view of a ceiling grid assembled from the grid runners of the invention as viewed from below; 
         FIG. 2  is a view similar to  FIG. 1  on an enlarged scale; 
         FIG. 3  is a side elevational view of a pair of opposed cross runners of the invention prior to assembly with a through runner of the invention; and 
         FIG. 4  is a side elevational view of the cross runners of  FIG. 3  after they are joined together with the through runner. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Conventionally, main runners, 12 feet long, are joined end-to-end to span the length or width of a ceiling. Cross runners of 4 foot length intersect adjacent pairs of parallel main runners at right angles. Shorter cross runners of 2 foot length can intersect pairs of adjacent parallel 4 foot cross runners. Herein, the term “through runner” will mean either a main runner or a cross runner that is intersected by a cross runner. Dimensions are to be understood to include industry metric equivalents. 
     In  FIGS. 1 and 2 , through runners in the form of main runners are indicated by the numeral  11  and cross runners are indicated by the numeral  12 . As will be seen, where runners  11 ,  12  are joined, they construct a faux miter joint, i.e. an intersection that creates the appearance of a miter joint when viewed from below. 
     The through and cross runners  11 ,  12  have the same cross section, the through runner cross section being shown most clearly in  FIGS. 3 and 4 . The runner cross section is symmetrical about an imaginary central vertical plane. A runner  11 ,  12  has an upper hollow reinforcing bulb, a double layer vertical web  14 , and a V-shaped lower flange  15  at the bottom of the web  14 . The runners  11 ,  12  are roll formed of two strips of metal which can be hot dipped galvanized steel. A main body strip  18  is folded to make the bulb  13 , layers of the web  14  and upper side of the flange  15 . The other strip  19  forms a visible lower side of the flange  15 . The flange  15  is the face of a runner  11 ,  12 , being visible from below a ceiling installation. The strip  19  can be painted on its lower side and its longitudinal margins can be folded over longitudinal edges of the main body  18  to permanently assemble these strips together. 
     The strips  18 ,  19  are roll formed into the illustrated and described cross sectional shape of the runners  11 ,  12 . The main body strip  18  can have a nominal gauge thickness of 0.016″ for main runners and 0.014″ for cross runners while the face or flange strip  19  can be a lighter gauge of for example 0.0085″. The layers of the web  14  can be locked together with integral stitching along the length of a runner  11 ,  12 , preferably near the bottom of the web. By way of example, the grid runner can have a height of 1 13/16″ and a flange width of about 9/16″. The V-shaped flange  15  is preferably formed with a flat  23  of relatively narrow width. Alternatively, the flange  15  can be formed without the flat  23 . The inclined sides of the flange  15  are designated with the numeral  24 . The width of the bulb  13  is a conventional ¼″. Aesthetically, it may be desirable for the flat bottom  23  of the flange  15  to be as narrow or, as shown, narrower than the width of the bulb  13 . In such a case, prior to finish roll forming of the flange  15 , the main body strip  18  can be scored at desired bend lines  27  on the side of the main body sheet or strip away from the main part of the face strip  19 . The score lines are made where the desired bends  27  are to be located at the transition from the flat  23  to the inclined side portions  24 . By scoring and thereby weakening the main body strip  18 , the composite of the body strip  18  and face strip  19  can be formed in a roll set without the need to locally support the upper side of the flange flat  23  in an area beneath the bulb  13 . This scoring technique can be similarly used in a flange configuration having essentially no flat  23 . 
     Prior to completion of the roll forming process, the runners  11 ,  12  can be fitted with end connectors.  FIGS. 3 and 4  show cross runners  12  assembled with end connectors  31 . The illustrated end connectors  31  can be of the separate connector type shown in U.S. Pat. No. 5,761,868 or of any other suitable type either in the form of a separate piece or integrally formed in the web of the runner. End connectors for a main through runner can be of a type for example shown in U.S. Pat. No. 7,703,258 or any other suitable type, again, whether a separate piece or integrally formed with the runner stock material. A main runner can be joined with another main runner at a butt joint. 
     The ends of cross runners  12 , including the end connectors  31  at the left and right in  FIGS. 3 and 4  are identical. The end of a cross runner  12  has its web  14  and flange  15  trimmed so that the lowest parts of these elements project longitudinally beyond other parts of the runner. This trimming can be performed, for example, in a press when other details are formed and where separate connectors  31  are attached to a preform of the runner and before it is finish rolled. As shown in the side elevation of  FIG. 3 , cut end edges  32  of the inclined flange sides  24  are inclined away, i.e. towards the main length of the runner  12  from a cut end edge  33  of the flange flat  23 . In the illustrated arrangement, these cut end edges  32 ,  33  are all in a common inclined plane that lies at an angle of, for example, 32 degrees off the vertical and is perpendicular to the plane of the web  14 . 
     Through slots  34  are regularly spaced along the length of main through runners and at the center of cross runners serving as through runners. 
     The cross runner end connectors or clips  31  are joined by inserting them in a common through runner slot  34  where they mutually self-index by snapping and locking together in a known manner. The illustrated end connectors  31  are locked together when a forward vertical strap or bar  37  snaps into a pocket  38  formed by opposing projections  39  on the opposite connector. The relative positions of the cut end edges  32 ,  33  and a respective connector  31  of each cross runner  12  are specially arranged. The arrangement causes the cross runner end edges  32  to produce a small resilient local deflection in bending of the through runner flange side  24  which they abut. As a result, at the intersection of a cross runner  12  at each side of a through runner  11 , the through runner flange side  24  closely fits against the end edges of the cross runner. This resiliently stress condition of the through runner assures that a faux miter joint between a through and cross runner is made without a visible gap. 
     The sides  24  of the through runner V-flange  15  are formed at an angle off the vertical that is preferably slightly greater, e.g. 0.5 to 3 degrees, than the angle of the plane of the cut end edges  32 ,  33  of the flange  15  of a cross runner. For example, where the angle of the plane of the cut end edges is 32 degrees, the flange sides  24  can be roll formed into planes 31 degrees off the vertical, i.e. the plane of the web  14 . Ideally, the planes of the cross runner flange sides  24  have the same angular orientation off the vertical as do the flange sides of the through runners. 
     It should be evident that this disclosure is by way of example and that various changes may be made by adding, modifying or eliminating details without departing from the fair scope of the teaching contained in this disclosure. The invention is therefore not limited to particular details of this disclosure except to the extent that the following claims are necessarily so limited.