You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
   In many stairway structures it is desirable to provide for replaceable stair treads and for supporting the stair treads securely. Proper support of glass stair treads, for example, has been a somewhat vexatious problem in the art of stair tread support systems. The support system should, of course, avoid concentration of support forces on the stair tread, securely retain the stair tread in its working position, preferably offer some cushioning for reacting forces exerted on the stair tread when being traversed by pedestrians, and minimize noise transmission or amplification from the stair tread to the stairway structure. It is to meet the desiderata and needs of stair tread support systems that the present invention has been developed. 
   SUMMARY OF THE INVENTION 
   The present invention provides an improved stair tread support system and stair tread support member. 
   In accordance with one aspect of the present invention, opposed stair tread support members are provided which are particularly adapted to releasably support generally planar stair treads in a manner which suitably secures the stair tread in a fixed working position while also providing for easy removal and replacement or repair of the stair treads, if and when needed. In particular, the stair tread support members are adapted for supporting glass stair treads, for example. 
   In accordance with yet a further aspect of the present invention, a stair tread support member is provided which includes a generally planar plate-like base part, a first integral transverse support flange and a second support flange disposed spaced from the first flange, and also integrally formed with or detachably connected to the base part. A stair tread cushioning member is adapted for placement on the first flange and engageable with the base part and the second flange. The second flange may also be formed as a separate part releasably securable to the base part by mechanical fasteners. 
   Still further, in accordance with the invention, a stair tread support member is provided including one or more threaded fasteners threadedly engaged with a second flange and with a tread member or a cushioning member interposed the tread member and the fastener for securing the tread member to the tread support member. The tread support member may further include an elongated removable trim cap for covering the heads and/or threaded openings for receiving the tread or flange retaining fasteners. Opposed removable retainers may be releasably secured to the tread support member at opposite ends thereof. 
   Those skilled in the art will further appreciate the above-mentioned advantages and superior features of the invention together with other important aspects thereof upon reading the detailed description which follows in conjunction with the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a portion of a stairway which includes a stair tread support system and support members thereof in accordance with the invention; 
       FIG. 2  is a perspective view of one preferred embodiment of a stair tread support member in accordance with the invention; 
       FIG. 3  is an exploded transverse view of the stair tread support member shown in  FIG. 2 , and including a tread cushioning member; 
       FIG. 4  is a detail view showing the tread support member illustrated in  FIG. 3  in assembly with and securing a stair tread; 
       FIG. 5  is an exploded transverse view of an alternate embodiment of a stair tread support member in accordance with the invention; and 
       FIG. 6  is a detail view showing the stair tread support member lustrated in  FIG. 5  in assembly with and securing a stair tread. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   In the description which follows like parts are marked throughout the specification and drawing with the same reference numerals, respectively. The drawing figures may not be to scale and certain elements may be shown in generalized or somewhat schematic form in the interest of clarity and conciseness. 
   Referring to  FIG. 1 , there is illustrated a portion of a stairway, generally designated by the numeral  10 , including a stair tread support system in accordance with the invention. Stairway  10  includes opposed parallel extending stringer members  12  and  14  which are characterized as generally planar members in the embodiment illustrated. Stairway  10  also includes spaced apart tread members  16  which are also characterized as generally planar, rectangular members and, in the embodiment shown, are preferably formed of glass or a similar transparent or translucent material of aesthetically pleasing quality. The tread members may each be a unitary member or “built-up” of plural laminated plate-like members. The tread members  16  are supported between and on the stringers  12  and  14  by an improved support system including opposed tread support members  18 , respectively. The tread support members  18  are of identical and symmetrical configuration and may be used on either of stringers  12  or  14 . 
   Referring now to  FIGS. 2 and 3 , there is illustrated in further detail one of the tread support members  18  of the present invention. Tread support member  18  includes a generally planar, elongated base part  20  delimited by a lower transverse end  22 , an upper transverse end  24  and opposed longitudinal end walls  26  and  28 . An integral transverse support flange  30  projects normal to the inwardly facing planar surface  20   a  of base part  20  and is reinforced by a longitudinally extending strut part  32  which is also, preferably, formed integral with the flange  30  and the base part  20 . Flange  30  is of a greater width than a second flange also integrally formed with the base part  20  and generally designated by the numeral  34 . Flange  34  is spaced from flange  30  and both flange  34  and flange  30  are provided with opposed facing planar parallel surfaces  34   a  and  30   a , respectively. Flange  34  is provided with a longitudinally extending upward facing so-called T-shaped or dovetail-shaped slot  36  which opens to the end walls  26  and  28  of the tread support member. Flange  34  is also provided with spaced apart tread fastener receiving holes or openings  38 , one shown in  FIG. 3 , each for receiving a sockethead type thread fastener  39  also as shown in  FIG. 3 . Threaded opening  38  extends between surface  34   a  and a surface  34   b  delimiting the upper surface of flange  34 . 
   Referring further to  FIGS. 2 and 3 , a lower portion  20   k  of base part  20  is provided with spaced apart fastener receiving openings  20   m  for securing the tread support member  18  to one of the stringers  12  and  14  using conventional mechanical fasteners, not shown. Still further, as shown in  FIG. 3 , the tread support system of the invention includes a somewhat “L” shaped tread cushioning member  40  including a base part  40   a  and an upstanding leg part  40   b  integrally formed with the base part  40   a  and extending at a right angle thereto. A separate cushioning member cap part  42  may form part of the cushioning member  40  but is preferably formed as a separate member. Stair tread cushioning members  40  and  42  are preferably formed of a clear silicone composition. 
   Referring still further to  FIGS. 2 and 3 , an elongated trim cap  44  is provided for the flange  34  and includes a T-shaped or dovetail base  46  and a generally planar head portion  48 . Cap  44  may be inserted in the slot  36  from one end wall  26  or the other end wall  28  of the tread support member  18  once the fasteners  39  have been inserted in their working positions, see  FIG. 4 . As shown in  FIG. 2 , opposed, removable tread retainer plates  41  may be releasably connected to tread support member  18  by suitable fasteners  45 , two shown, for securing the plates to end walls  26  and  28 , respectively. 
   Referring further to  FIG. 4 , there is illustrated the tread support member  18  completely assembled and also supporting one end of a tread member, such as the tread member  16 . Tread member  16  may be a single thickness plate-like member or a laminated member made up of plural plate-like members  16   a ,  16   b  and  16   c , as illustrated. Thanks to the cushioning member  40 ,  42 , the fasteners  39  and the configuration of the flanges  30  and  34 , the tread member  16  may be securely fastened to the tread support members  18  at opposite ends,  FIG. 1 , while at the same time each cushioning member  40 ,  42  minimizes shock loading of its associated tread support member and minimizes the transmission of vibrations from the tread member to the remainder of the stairway system. It will be appreciated by those skilled in the art that the tread members  16  may be easily replaced when needed by removal of the cap  44  for each tread support member  18 , loosening or removal of the fasteners  39  and then sliding the ends of the tread members out of the slots formed between the flanges  30  and  34 . Tread support members  18  may be formed of extruded metal or plastic, for example, and provided in aesthetically pleasing colors or surface finish and the tread support members  18  may also be easily replaced on the stringers  12  and  14 , if desired. 
   Referring now to  FIGS. 5 and 6 , there is illustrated another preferred embodiment of a stair tread support member in accordance with the invention. A stair tread support member  18   a  is shown in  FIG. 5  in an exploded transverse or end view corresponding to  FIG. 3  in some respects. The tread support member  18   a  includes a generally planar base part  21  delimited by an upper edge  24   a  and a lower edge  22   a . An integral flange  30  extends transversely to the base part  21  and defines surface  30   a  normal to a surface  21   a  delimiting an upper portion of the base part of the tread support member  18 A. A difference in the configuration of the tread support member  18   a , as compared to the tread support member  18 , is that an upper portion of the base part  21  is of a greater width than that of the member  18  in order to accommodate one or more fastener receiving openings  38   b , and a separable upper flange  35  which is provided with an elongated T-shaped or dovetail slot  36  but is also provided with one or more fastener receiving openings  35   a  to receive a threaded fastener  39   a , preferably a sockethead machine screw, operable to secure the upper flange  35  to the base part  21  and to also operate to secure a tread between a lower surface  35   b  of separable upper flange  35  and the surface  30   a  of integral flange  30 . A slightly modified cushioning member  40   d  is provided with opposed integrally joined right angle oriented parts  40   e  and  40   f . A separate cushioning strip  43  is provided corresponding to the strip  42 . 
   As shown in  FIG. 6 , the tread support member  18   a  is operable to secure a single or laminated tread, such as the tread  16 , by placing the cushioning member  40   d  on surface  30   a  and bearing against surface  21   a  whereby the tread  16  may be securely clamped to the member  18   a  by the separable flange  35  using the recessed or sockethead screws  39   a , one shown in  FIG. 6 . The cap  44  is disposed in slot  36  of separable flange  35  once the recessed sockethead screws  39   a  are disposed in their counterbored receiving openings  35   a , as illustrated. Of course, the length of the tread  16  may require to be shortened slightly or the span between the stringers  12  and  14  may require adjustment for use of the tread support members  18   a  taking into consideration the thickness of the upper part of the base member  21  which defines the surface  21   a.    
   The construction and operation of the tread support system and the tread support members  18  and  18   a  of the present invention are believed to be readily understandable to those skilled in the art based on the foregoing description. Conventional engineering materials may be used to provide the support members  18  and  18   a , as well as the cushioning members  40 ,  40   d ,  42  and  43 , as previously mentioned. Although preferred embodiments of the invention have been described in detail, those skilled in the art will recognize that various substitutions and modifications may be made without departing from the scope and spirit of the appended claims.

Summary:
A stair tread support member for releasably supporting generally planar stair tread members including stair tread members made of glass or other transparent material includes a general planar base part adapted to be supported on a stairway stinger. The tread support member includes spaced apart flanges forming a channel shaped slot for receiving and supporting a stair tread member. A cushioning member may be interposed the support flanges and the stair tread member. Removable threaded fasteners are engageable with the second flange for retaining the stair treads secured to the tread support member. An elongated cap fits in a slot in the second flange and covers the fasteners.