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You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to suspended ceiling systems and, in particular, to an improved wall molding for use in such systems. 
       PRIOR ART 
       [0002]    Where a suspended ceiling meets a wall, it is customary to provide a sheet metal wall angle. This wall angle serves to support the edges of ceiling panels or tiles and the ends of grid runners and to conceal normal gaps between these edges and ends and the wall. Walls conventionally constructed of drywall are often not flat because of the presence of corner bead, taped joints, and other disturbances. These irregularities can be especially pronounced where a space is being remodeled and walls are reconfigured. Standard metal wall angles, while ordinarily made of light gauge steel, are relatively stiff owing to the right angle geometry. As a result, ordinary wall angle often does not closely follow the irregularities in a wall and unsightly gaps between the wall angle and the wall can exist. While it is customary to conceal such gaps with caulk, this technique is undesirable as a solution to the problem of unsightly gaps. Efforts to force the wall angle into full contact with an irregular wall surface can cause the wall angle to permanently buckle and present an even more unsightly condition. 
       SUMMARY OF THE INVENTION 
       [0003]    The invention provides a wall molding for suspended ceiling systems that is capable of conforming to ordinary deviations from a flat plane in the surface of a wall against which it is mounted. The inventive wall angle, in various embodiments, has a visible wall engaging area that, in a free state, projects from an upright component of the molding toward the wall. When the upright component of the molding is drawn against the wall surface, the visible wall engaging area retracts towards a plane of the upright component. Where the upright component is not locally drawn against or close to the wall surface because adjacent wall areas bulge or recede from a flat plane, the retractable visible wall engaging area remains extended towards the wall. Consequently, unsightly gaps between the visible wall engaging area of the molding and the wall are avoided. Advantageously, the molding can be roll-formed of a single metal strip sufficiently hard or springy to allow the strip to resiliently flex and allow retraction of the visible wall engaging area or, if adjustment is needed, allow return of this area to its free state. In a first disclosed embodiment, a metal strip forming the molding body is folded in a manner such that the visible wall engaging area is formed along an edge of the strip that is opposite the edge on a side of the strip that projects to support ceiling panel edges and grid runner ends. When the upright component is drawn towards a wall during installation of the molding, the visible wall engaging area telescopes or slides under adjacent areas of the projecting component. 
         [0004]    In a second disclosed embodiment, a metal strip forming the molding body is folded in a manner such that the visible wall engaging area is at an edge of the side of the strip that forms the projecting component. The visible wall engaging area is enabled to retract by resilient, generally imperceptible distortion of large portions of the cross-section of the molding. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a fragmentary isometric view of a first embodiment of a wall molding of the invention; 
           [0006]      FIG. 1A  is a fragmentary isometric view of a modified form of the first embodiment of the inventive wall molding; 
           [0007]      FIG. 2  is a fragmentary isometric view of a second embodiment of a wall molding of the invention; and 
           [0008]      FIG. 2A  is a fragmentary isometric view of a modified form of the second embodiment of the inventive wall molding. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0009]    Referring now to  FIG. 1 , a suspended ceiling system  10  is represented by a ceiling panel or tile  11  and a grid runner or tee  12 . The panel  11  and tee  12  can be standard commercially available products and, as is conventional, are duplicated across the expanse of a ceiling.  FIG. 1  represents an edge of the ceiling system  10  where it intersects with a wall  13 . The wall can be constructed of drywall sheets indicated at  14  secured to vertical studs (not shown) or other structure at the backside thereof. 
         [0010]    Where drywall sheets  14  are joined, particularly where their ends are abutted and taped or where they intersect at an outside corner and are capped with a corner bead and joint compound, the wall will have localized bulges meaning that the wall surface deviates from a flat plane. A first embodiment of a wall molding  16  constructed in accordance with the invention is illustrated in  FIG. 1 . The molding  16  is secured to the wall  13  by fasteners  17  such as screws, nails, or staples. It is customary that the fasteners are driven through the drywall  14  into the underlying studs or other framework or support. Typically, the studs will be spaced horizontally a regular distance along the wall  13 . 
         [0011]    The wall molding  16  comprises a generally upright component  18  and a projecting component  19 . The wall molding  16 , preferably, is a single sheet of metal, typically steel sufficiently hard to exhibit a springiness or resilience as discussed below. The wall molding  16  while it can be brake-formed, is preferably roll-formed using conventional roll-forming techniques known in the industry. The upright component  18  comprises two layers  25 ,  26 . The outer layer  26  can be flat, as shown, or can be convex on the side facing the wall  13 . In the latter case, the plane of the upright component layer  26  can be taken as an imaginary plane, vertical or nearly vertical, that passes through its upper and lower extremities indicated at  21 ,  22 , respectively. 
         [0012]    The projecting component  19  of the molding  16  comprises first and second parts  23 ,  24 . The wall molding  16  has a constant cross-section extending along its length. The length of the wall molding typically is 10′ or 12′ or metric equivalent. The first part  23  of the projecting component  19  is a relatively narrow horizontal flange carried at the bottom of the layer  25  made by folding the molding body on itself at the upper extremity  21  of the upright component. In the illustrated form of the wall molding  16 , the layer  25  is concave on its side facing the wall  13 . The first part  23  of the projecting component  19  exists along a side of the strip from which the wall molding  16  is made that is remote from the side of the strip forming the second part  24  of the projecting component  19 . The free edge of the projecting component first part  23  is hemmed at  27  by folding the sheet material back on itself, the hem being on an upper side of this first part. 
         [0013]    The projecting component second part  24 , in the embodiment version of  FIG. 1 , is stepped such that it includes two horizontal segments  28 ,  29  joined by a vertical segment  31 . The horizontal segment  29  comprises one of the lateral or marginal sides of the strip forming the wall molding  16 . A distal free edge  32  of the horizontal segment  29  is provided with a hem  33  folded back on its upper side. 
         [0014]    The upright component  18  and the second part  24  of the projecting component  19  are relatively stiff in vertical and horizontal planes owing to their right angle character. This means that the upright component  18  and horizontal segment  28  will not readily follow the contour of the wall  13  where it deviates from a flat plane even when the fasteners  17  are forcibly urging the upright component towards the wall  13 . 
         [0015]    The forefront of  FIG. 1  depicts a location on the wall that is recessed from an adjacent area or areas at the same elevation. That is, areas of the wall horizontally spaced from the plane of the forefront of  FIG. 1  can be considered to be bulging as a result of, for example, a butt joint between sheets of drywall or a corner bead. Inspection of  FIG. 1  shows that the gap at the surface of the wall  13  with the segment  26  forming part of the upright component  18  and the second part  24  of the projecting component  19  is concealed by the first part  23  of the projecting component  19  which engages the wall at a line  34  formed at a corner between the upright component layer  25  and the first part of the projection component. Where the wall is flat along an extended line or where a bulge occurs, a fastener  17  can draw the upright component layers  25  and  26  against one another and the layer  25  against the wall  13 . When being drawn towards the wall, the layer  25  causes the first part  23  of the projecting component to telescope or slide under the horizontal segment  28  of the second part  24  of the projecting component  19 . It will be seen that the molding  16  conforms to normally expected deviations in the flatness of the wall by concealing gaps which may result from such deviations since the projecting component first part  23  bridges a gap between the wall  13  and the relatively stiff generally right angular configuration of the upright component layer  26  and second part  24  of the projecting component  19 . The edge view of the wall molding  16  shown in the forefront of  FIG. 1 , reveals the cross-sectional configuration of the wall molding  16  essentially in its free state. Ideally, the metal used to make the wall molding  16  is sufficiently hard or springy so that it will assume this free state configuration even after it has been tightened against a wall with a fastener and then released in case final adjustments need be made to optimize appearance. 
         [0016]      FIG. 1A  illustrates a wall molding  36  that is a variant of the wall molding  16 . Elements of the wall molding  36  having the same or essentially the same function as that described in connection with the wall molding  16  of  FIG. 1  are identified with the same numerals. The wall molding  36 , as compared to the molding  16 , has a projecting component second part  37  that is a simple horizontal segment terminated at a distal edge  38  with a hem  39  turned on its upper face. The wall molding  36  works in essentially the same way as the wall molding  16  to conceal gaps between the wall  13  and the upright component layer  26  and second part  37  of the projecting component  19 . 
         [0017]    Referring now to  FIG. 2 , there is shown a second embodiment of a wall molding  41 . Identical or similar elements to that described in connection with  FIG. 1  are identified with the same numerals in  FIG. 2 . The wall molding  41  as in the previous wall moldings  16 ,  36  is preferably roll-formed of half hard sheet steel of light gauge. The free state cross section of the wall molding  41  is illustrated in the foreground of  FIG. 2  and is continuous along its length which, again, can be in the order of 10′ or 12′ or metric equivalent. The wall molding has an upright component  42  and a projecting component  43 . The upright component  42  is generally planar extending upwards from a corner  44  it shares with the projecting component to an upper hemmed edge  46 . 
         [0018]    The projecting component  43  comprises a C-shaped channel  47  comprising an upper horizontal segment  48 , a generally vertical segment  49 , and a lower generally horizontal segment  51 . 
         [0019]    The lower segment  51  is somewhat longer than the upper horizontal segment  48 . The result of this geometry, as depicted in  FIG. 2 , is that a free edge  52  of the lower horizontal segment  51  extends inward toward the wall  13  beyond a plane in which the upright component  42  lies. The generally right angle configuration at the corner  44  of the upright component  42  and the projection component horizontal segment  48  is relatively stiff so that a gap between this corner  44  and the wall  13  can exist where the wall is uneven. However, the inherent flexibility of the cross-section of the wall molding other than about a vertical axis will allow the free edge or line  52  to extend to the surface of the wall  13  even where a gap exists between the corner  44  and the wall. When the wall is sufficiently flat the fasteners  17  draw the upright component  42  against the wall  13 . The fastener  17  can be adjusted to accommodate variations in the wall plane. The free edge  52 , owing to the resilient compliance of the wall molding  41  through local, essentially imperceptible distortion of the wall molding cross-section can retract towards the plane of the upright component  42 . Otherwise, the gap between the corner  44  and wall  13  would be visible. 
         [0020]    Referring now to  FIG. 2A , a modified form of the second embodiment of the inventive wall molding is shown at  56 . The same numerals are used in  FIG. 2A  as that used in  2  for components of the wall moldings  41  and  56  that are the same or equivalent. The wall molding  56  has a projecting component  43  comprised of a V-shaped channel  57 . The wall molding cross-section in its free state is shown at the forefront of  FIG. 2A . It will be seen that the free edge  52  extends inward of the plane of the upright component  42  so that the wall molding  56  performs essentially the same way as the wall molding  41  in conforming to the contour of a wall and concealing any gap that may exist between the corner  44  and the wall where normal irregularities in the wall may exist. 
         [0021]    Common among the various disclosed embodiments of the wall molding is that the visible wall engaging part, in the free state and proper orientation, extends inwardly in the direction of the wall beyond the plane of at least one layer of an upright component. 
         [0022]    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.

Summary:
A wall molding for a suspended ceiling comprising a roll-formed sheet metal body having a generally upright component to be fixed to a wall and a projecting component extending generally transversely to the upright component and adapted to underlie and support the edges of ceiling tiles and ends of grid runners, the projecting component in a free state extending across a plane defined by the upright component to a line adapted to abut the wall when the upright component is drawn towards the wall.