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BACKGROUND OF THE INVENTION 
     The invention relates to mounting systems for decorative wall panels. 
     PRIOR ART 
     Prior arrangements for mounting an array of rectangular metal ceiling panels on vertical walls or like surfaces have required expensive, specially produced hardware. Prior art hardware for such systems was limited in the depth that was afforded behind the panels for backlighting or other effects and could not protect central areas of the panels from damage when struck accidentally or from vandalism. 
     SUMMARY OF THE INVENTION 
     The invention provides unique systems for mounting rectangular metal ceiling panels on a wall or other vertical surface. The disclosed mounting systems are relatively inexpensive and use, for the most part, standard hardware and common construction materials. 
     In one embodiment of the invention, the mounting system utilizes various standard suspension ceiling components to support the rectangular panels. The invention, as a result of adopting standard components, reduces system costs and requisite skill and labor for installation. Moreover, the invention makes it practical to offer several different standoff dimensions from wall to rectangular panel. 
     In another embodiment of the invention, a backer panel is configured to provide both a mounting function and damage resistance for a metal ceiling panel. The backer panel or board can be constructed of a common construction material such as MDF (medium density fiberboard). The backer panel can be produced with minimal tooling investment and requires minimal accessories for a finished installation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic isometric view of a wall on which is installed an array of rectangular panels; 
         FIG. 2  is a fragmentary cross-sectional view, indicated by the arrows A-A in  FIG. 1  of a perimeter area of the installation according to a first embodiment of the invention; 
         FIG. 2A  is an exploded fragmentary view of a clip mounting a perimeter trim channel on a grid runner mounted on a wall; 
         FIG. 3  is a fragmentary cross-sectional view, indicated by the arrows B-B in  FIG. 1  showing details of a typical joint between two adjacent panels; 
         FIG. 4  is an isometric view of a bracket used to mount tees that support peripheral edges of the decorative panels of the first embodiment; 
         FIG. 5  is a front face view of a backer board for a decorative panel in accordance with a second embodiment of the invention; 
         FIG. 6  is a typical edge view of the inventive backer board of  FIG. 5 ; 
         FIG. 7  is a cross-sectional view of a peripheral area of a decorative panel installation with the mounting system of the second embodiment taken at the line A-A of  FIG. 1 ; and 
         FIG. 8  is a fragmentary cross-sectional view of a central area of the decorative panel mounting system of the second embodiment taken at the line B-B of  FIG. 1 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  schematically illustrates a wall or like vertical support  10  on which an array of metal ceiling panels  11  are mounted with a system of the invention. The ceiling panels  11  are generally known in the construction industry such as those marketed under the trademark Celebration™ by USG Interiors, LLC. The panels  11 , formed of high strength steel or hard aluminum are pan-shaped, having nominal face dimensions typically of 2 foot×2 foot or industry metric equivalent. Edges of the panels are formed with flanges  12  generally perpendicular to the panel face. The flanges are somewhat reentrant at their mid-sections  13  for purposes of securing the panels to a mounting structure. Ordinarily, the panels will only be mounted on a local area of the wall  10  to provide a design feature; the array of panels  11  should be spaced from the floor to avoid being struck by carts and floor sweepers and like equipment. 
       FIGS. 2-4  illustrate details of a first embodiment of the invention for mounting panels  11  on the wall  10  with sufficient space to effectively backlight the panel with a light source or sources (not shown) disposed between a panel  11  and the wall. A matrix or grid of “bolt slot” runners  14  is utilized to support the panels  11  in spaced relation to the wall  10 . Preferably, the runners  14  are arranged with main runners on 24 inch centers and cross runners similarly on 24 inch centers. Industry metric equivalents of these dimensions can be used. 
     Main runners  14 , conveniently arranged vertically on the wall  10  are supported by spaced wall mounting brackets  16  shown in  FIG. 4 . The brackets  16  can, for example, be spaced along the main runners  14  at a regular distance between successive cross runners, i.e. on 24 inch centers. The brackets  16  can be proportioned to support the ceiling panels at a desired distance of, for example, 4 inches, 6 inches, or 8 inches from the wall  10 . The brackets  16  are provided with slots  17  to receive self-tapping screws  18  that are driven into a web  19  of the main runner  14 . The slots  17  afford a limited adjustability to accommodate tolerances in assembly of the various parts and variations of flatness in the wall  10 . When a runner  14  is properly adjusted, a screw  18  can be used in a hole  21  to lock the runner in place. The brackets have feet  15  with holes for accepting screws to mount the brackets on the wall  10 . 
     It is desirable that the array  25  of panels  11  have as its periphery  26  suitably trimmed to conceal the mounting details and give the array  25  a finished appearance. In the embodiment illustrated in  FIGS. 2-4 , the periphery  26  can be trimmed by standard suspended ceiling island trim such as that marketed by USG Interiors, LLC under the trademark Compasso®. This trim system includes brackets  27  which attach to the runners  14  and trim channels  28  to form a continuous outline at the periphery  26  of the array of panels  11 .  FIG. 2A  illustrates a runner  14 , bracket or clip  27 , and trim channel  28  in exploded relation. With reference to  FIGS. 2 and 2A , the grid runner  14  is fixed to the wall  10  by the bracket  16  and the trim channel is fixed to the grid runner  14  by the clip  27 . The clip  27  is secured to a reinforcing bulb  29  and/or web  30  of the runner with self-tapping screws. It will be seen that the clip  27  has flanges  31  that interengage with hems  32  on narrow flanges  33  of the shallow trim channels  28 . The grid members or runners  14  can be of the type marketed under the trademark FINELINE® by USG Interiors, LLC. Besides the illustrated attachment clip  27 , the suspended ceiling industry offers accessories for the trim channel  28  which include outside corners and splices. 
     It will be seen from  FIGS. 2 and 3  that the panels  11  are snapped onto flanges  36  forming the bolt slots of the runners  14 . The utilization of standard suspended ceiling grid components including the runners  14 , clips  27 , and channels  28  enable the construction of a wall mounting system for the ceiling panels  11  which is economical and readily installed by technicians who are familiar with suspended ceiling technology. The adaptation of these suspended ceiling accessories to a wall mounting system greatly reduces costs to a manufacturer since the majority of components are already in existence. The outside corners, typically, are factory made, greatly simplifying field construction of the array. Conventional metal ceiling panels are perforated with uniformly spaced holes running along orthogonal lines parallel to the edges of the faces of the panels. More recently hole or perforation patterns have been arranged to depict the image of an object. These perforated ceiling panels can be backlit, i.e. provided with a light source between the panel and the underlying wall supporting the panel array for a dramatic effect. The arrangement of the runners provided by the present invention allows adequate space, for example, 4, 6 or 8 inches between the panel and wall to provide adequate spacing to obtain a uniform light distribution. A compressible foam rubber strip  37  can be adhesively attached to the flanges  33  of a trim channel  28  to block any light from the space enclosed by the panels  11  and trim channels. Backlighting of apertured panels  11  is particularly desirable where the apertures create an image by their placement and size; an example of commercially available panels having this feature is the product line marketed under the mark PIXELS® by USG Interiors, LLC. 
       FIGS. 5-8  illustrate details of a backer board  40  constructed in accordance with a second embodiment of the invention. The backer board  40 , preferably, is made from medium density fiberboard (MDF), although it may be made of other similar material suitable for this purpose. The board is nominally 24 inches square (or industry metric equivalent). Preferably, the backer board or panel  40  has a thickness of ¾ inch (or industry metric equivalent). Each edge  41  of the board  40  is routed with an identical profile. A base or backside  43  of the backer board  40  has the referenced nominal 24 inch dimension. This backer base has a thickness slightly less than a third of the total thickness of the backer board  40 . A deep groove  44  separates the base  43 , at the periphery of the board  40 , from an undercut central area  46 . Forward of the undercut area  46 , the edge profile is enlarged at a band  47 , thus forming a rearwardly facing shoulder surface  48 . Forward of the band  47 , the edge profile includes a beveled surface  49  which in the illustrated instance, lies in a plane 15 degrees off a line perpendicular to the plane of the board  40 . On a rear face  51  the board are small elastomeric standoffs or bumpers  52  adhesively attached diagonally inward from a respective corner. The elastomeric or rubber standoffs  52  serve to bridge the panel across irregularities on a wall surface to which it is attached. On a forward face  53 , the backer board  40  has a set of four countersunk through holes  54 , one adjacent each corner of the board. 
     A plurality of boards  40  are secured in a rectangular array, such as that depicted in  FIG. 1 . The board  40  can be attached to a wall  10  by self-drilling screws (not shown) positioned in the countersunk holes  54  and screwed into the wall  10 . As indicated in  FIG. 8 , which corresponds with the section lines B-B in  FIG. 1 , the boards  40  are abutted against adjacent boards. Inspection of  FIGS. 7 and 8  reveals that the edge profile  41  is configured to receive a flange  12  of a metal ceiling panel  11 . The reentrant area  13  of a flange  12  is adapted to be received in the peripheral valley of a board  40  bounded by the shoulder surface  48 , undercut area  46 , and base  43 . The bevel surface  49  on the periphery of the board  40  operates as a cam to cause a respective panel flange  12  to spread slightly outward as a panel  11  is forced onto a board until the reentrant area  13  snaps into the valley behind the rearward facing shoulder surface  48 .  FIGS. 7 and 8  show that when a panel  11  is mounted on a backer board  40 , the entire face of the panel is backed up by the board. This back-up function of the backer board  40  reduces the potential for a panel  11  to be dented or creased inward or otherwise damaged. 
     Referring to  FIG. 7 , which corresponds to the section lines A-A of  FIG. 1 , the array of backer boards  40  can be trimmed at its periphery by an edge trim piece  57  having a generally F shape cross-section. As indicated in  FIG. 7 , one flange  58  of the trim  57  slips behind the backer board  40  while a central flange  59  of the trim is received in the deep narrow groove  44 . The trim  57  can be installed before the screws in the holes  54  are fully tightened. The spacing between the wall  10  and backer board  40  provided by the rubber standoffs  52  facilitates the reception of the trim flange  58  behind the backer boards. 
     The illustrated backer boards  40  can be manufactured at very low cost since they are constructed of a common construction board stock and their edge profile  41  can be cut with a single router or shaping bit. 
     While the invention has been shown and described with respect to particular embodiments thereof, this is for the purpose of illustration rather than limitation, and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention. Accordingly, the 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.

Summary:
Mounting systems for attaching metal suspended ceiling panels to form a decorative rectangular array. In one system the panels are mounted on bolt slot grid runners spaced from the wall and trimmed with island ceiling trim. In another system, panels are mounted on unique backer boards that protect the panels against physical damage by resisting compressive forces on the face of the panels.