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RELATED APPLICATIONS 
       [0001]    The herein disclosed subject matter is closely related to that of the inventor&#39;s co-pending U.S. patent application Ser. No. ______ filed ______ for a Method Of Merchandising Complementary Medallions which is incorporated herein by reference. 
     
     BACKGROUND OF THE INVENTION 
       [0002]    Ceiling medallions in the form of decorative disks are used to accent or enhance the appearance of a ceiling fixture, such as a light fixture or ceiling fan. The medallions are decorative and a variety of surface ornamentations are used to provide the desired aesthetic effect. There are a great many variations in room decor and there are many differences in personal preferences concerning interior decoration thus giving rise to a need for a wide variety of ceiling medallions. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0003]    A relatively large annular base plate or disk includes concentric annular recesses in which interchangeable decorative rings may be releasable mounted. The decorative effect of the medallion can be changed by choosing from several differently decorated rings and inserting the chosen ring in the mating annular recess. A base plate with two concentric annular recesses permits a variety of medallion designs to be produced by choice of inserted ring or rings. The chosen ring is inserted into the recess and rotated to bring mating detent components into registry or engagement in snap lock fashion, which releasably holds the ring in its associated recess. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    The construction of medallion base plates, insertable rings and plate plus ring combination are illustrated in the drawings, in which: 
           [0005]      FIG. 1  is a front view of a first medallion base plate; 
           [0006]      FIG. 2  is a front view of a second medallion base plate; 
           [0007]      FIG. 3  is a front view of a large decorative ring; 
           [0008]      FIG. 4  is a front view of a decorative ring that is smaller than the ring of  FIG. 3 ; 
           [0009]      FIG. 5  is a front view of a decorative ring which can be substituted for the decorative ring of  FIG. 4 ; 
           [0010]      FIG. 6  shows the ring of  FIG. 3  inserted into a large annular recess in the base plate of  FIG. 1 ; 
           [0011]      FIG. 7  shows the ring of  FIG. 4  inserted into an annular recess of the base plate of  FIG. 1  which is concentric with but of smaller diameter than the large annular recess; 
           [0012]      FIG. 8  shows rings of  FIGS. 3 and 4  in the base plate of the medallion; 
           [0013]      FIG. 9  is a section taken on line  9 - 9  in  FIG. 8 ; 
           [0014]      FIG. 10  is a section taken on line  10 - 10  in  FIG. 9 ; 
           [0015]      FIG. 11  is a partial section showing the rings of  FIG. 3 and 5  installed in the medallion base plate; 
           [0016]      FIG. 12  is a partial front view a base plate and a ring showing notches, tabs and knobs which facilitate insertion and retention of the ring in the base plate and  FIG. 13  shows the ring of  FIG. 12  rotated counter clockwise 45 degrees bringing the knobs into a snap lock connection with the tabs. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    As shown in  FIGS. 1 and 9 , a medallion base plate  21  is provided which has a contoured outer annular ridge  22  at its radially outer edge. A shoulder  23  in the ridge  22  provides a decorative effect. The base plate  21  includes a somewhat smaller diameter annular ridge  26  and a flat bottom annular recess  27  between the ridges  22 ,  26 . The base plate  21  also includes an annular ridge  29  near its center  28 , which is somewhat higher than the intermediate ridge  26 , and a smaller diameter flat bottom recess  31  between the ridges  26 ,  29 . An opening  32  is provided in the center of the plate  22 . 
         [0018]    A base plate  36  shown in  FIG. 2  is similar to the base plate of  FIG. 1  except radially extending openings  37 ,  38  have been formed in the bottoms of the recesses  41 ,  42 , respectively, to produce a floral design. This configuration also saves material and produces a more ornamental appearance when the base plate  36  is used singularly as a medallion.  FIG. 3  shows a relatively large diameter annular decorative ring  44  which is insertable into the recess  27  of the base plate  21  or into the recess  41  of the base plate  36 .  FIG. 4  shows a smaller diameter annular decorative ring  46  which is insertable into the recess  31  of the base plate  21  or into the recess  42  of the base plate  36 .  FIG. 5  shows an ornamental ring  47  having a different central configuration which is insertable into the recess  31  of the base plate  21  or into the recess  42  of the base plate  36 . The ring  47  has a central annular opening  48  with a diameter slightly larger than the diameter of the central opening  32  in the base plate  21 . The rings  44 ,  46 ,  47 , and the plates  21 ,  36 , can be used separately as individual medallions and in various combinations. Thus a set of mix and match ceiling medallions is provided which may be advantageously marketed individually or as a package. 
         [0019]      FIG. 6  shows a medallion in which the large diameter decorative ring  44  is installed in the recess  27  of base plate  21  and there is no ring installed in the recess  31 .  FIG. 7  shows a medallion in which the smaller diameter ring  46  is installed in the annular recess  31  and the recess  27  is empty.  FIG. 8  shows a medallion in which the recess  27  is filled with the ring  44  and the recess  31  is fitted with the ring  47 . Using either ring  46  or ring  47  in the base plate  21  produces substantially the same decorative effect; however, when the rings  46 ,  47  are used individually as medallions there is a distinct difference in their appearance. 
         [0020]    Referring also to  FIGS. 9 ,  10 ,  11  and  12 , the radially inner shoulder of the outer annular ridge  22  has four radially inward projecting, and equally circumferentially spaced, detent elements in the form tabs  52  which are spaced axially from the flat bottom of the recess  27  and the radially outer shoulder of the intermediate ridge  26  has four radially outward projecting tabs or detent elements  52  spaced axially from the flat bottom of the recess  27 . The tabs  51  are aligned radially, respectively, with the tabs  52 . In similar manner, the tabs  56 ,  57  are formed on the shoulders of the ridges  26 ,  29 , respectively, so as to project into the recess  31  in axially spaced relation to its flat bottom. Each of the tabs  51 ,  52 ,  56 ,  57  has a curved pocket or socket  61  on it&#39;s under side facing the associated recess. One such socket  61  is shown in  FIG. 10 . 
         [0021]    Referring to  FIG. 3 , the decorative ring  44  has four radially outwardly open notches  66  at 90 degree intervals in its circumference and has four radially inwardly open notches  67  in its radially inner edge which are in radial alignment; respectively, with the notches  66 . Notches  71 ,  72  are formed in a similar manner in the decorative ring  46  as shown in  FIG. 4 . The decorative ring  47  shown in  FIG. 5  has four equally spaced radially inward extending notches  76  in its outer periphery and no notches in its inner diameter or central opening  32 . The notches  66 ,  67  on the ring  44  are sufficiently large to allow passage there through of tabs  51 ,  52 , respectively, when the large ring  44  is installed in the recess  27  and the notches  71 ,  72  are sufficiently large to allow passage there through of the tabs  56 ,  57 , respectively, when the small ring  46  is installed in the recess  31  of the base plate  21 . The notches  76  on the outer periphery or perimeter of the ring  47  are sufficiently large to permit passage of the tabs  56  when the ring  47  is installed in the recess  31  of the base plate  21 . There are no notches on the inner diameter of the ring  47 . 
         [0022]    Four detent elements in the form of four rounded or spherically shaped axially projecting knobs  81  are formed at equally spaced internals on the ring  44  near its radially outer edge and four detent elements or spherically shaped axially projecting knobs  82  are formed at  90  degree internals on the ring  44  near its radially inner edge. The knobs  81  are aligned radially with the knobs  82 , respectively. In a similar manner knobs  83 ,  84  are formed on the ring  46 . Knobs  86  are formed on the ring  47  at 90 degree intervals near its radially outer edge. 
         [0023]    The ring  44  can be installed in the recess  27  of the base plate  21  by aligning the notches  66 ,  67  with the tabs  51 ,  52 , respectively, and passing the tabs  51 ,  52  through the notches  66 ,  67 , respectively. The ring  44  is then rotated relative to the base plate  21 , as shown in  FIG. 6 , by an angle  91  of 45 degrees about the axis  28  to bring the knobs  81 ,  82  into a snap lock registration or detented relationship, respectively with the tabs  51 ,  52 . As shown in  FIG. 10  the knob  81  is releasably retained or detented in the socket  61  of the tab  51  in a snap lock engagement. The engaging surfaces of the tabs  51  and the knobs could be cylindrical in shape to provide a similar snap lock action when moved into and out of engagement. The tabs are made of a resilient material and flex during engagement with and disengagement from the knobs. The knobs on the ring could be circumferentially offset from the notches on such ring by an angle other than 45 degrees. 
         [0024]    the herein described mix and match ceiling medallions are advantageous for a number of reasons. Each medallion based plate and ring can be used independently or various base plate and ring combinations can be used to produce a multitude of decorative medallions. In merchandising, the floor space is minimized and the customer is provided more choices of final design. The medallion base plates and rings can be marketed in a single package. The base plates and rings can also be packaged and sold individually.

Summary:
A multiple component decorative medallion includes a decorative annular base plate adapted to receive decorative rings which are held in place by releasable detents. The base plate and the rings can be used individually as decorative medallions or selectively combined to produce a variety of ornamental images.