referring now to fig1 a , there is shown a perspective view of a common leg 10 that is used with a bed frame . in the figure , the leg 10 is shown as depending downwardly from a cross member 12 that is , in turn , affixed to a side rail 14 of the bed frame . as will be seen , in the preferred embodiment , the present invention will be described specifically with respect to its use with a bed frame , however , the overall invention is applicable for use with a wide variety of furniture items without departing from the spirit and intent of the invention . in the assembly and set up of a bed frame , the flames themselves are normally shipped to the user knocked down , that is , the cross members are pivotally affixed to side rails and , during assembly , the cross members are rotated to a point generally at a right angle with respect to the side rails and are then interconnected with a corresponding cross rail from the other side rail . as such , therefore , the legs of the bed frame are generally affixed to the cross members and will be so described herein , it being understood that the present invention may also be applicable to other positions and locations of the legs of a bed frame . as shown in fig1 a , therefore , the typical cross member is conventionally constructed of a steel member having an l - shaped cross section with a horizontal plane 16 that is pivotally affixed to the side rail 14 and a vertical plane 18 of the l - shaped cross member 12 extending downwardly toward the surface on which the bed frame rests . the leg 10 , itself , is a stamped steel member that is normal shaped to be tapered in the downward direction , such as in the shape of a truncated trapezoid and has an opening 20 that is of a predetermined standard diameter . the caster assembly 22 may be any variety of caster , however the caster shown is a glide that has a flat bottom and thus is suitable for use with a hard wood or tile floor . as will be seen , however , the particular caster that can be used with the present invention is not limited to a glide or , for that matter , any other specific caster , it only being of importance that the caster assembly , in the preferred embodiment , include an upstanding stem 24 of predetermined standard diameter , and being slightly tapered , so as to interfit into the opening 20 to thereby become firmly affixed to the leg 10 . again , as noted , the stem here would normally include a plastic bushing that interfits into the opening in the leg , however , with the preferred caster of this invention , the caster need not swivel and therefore , the stem may be metal and force fitted into the leg assembly . other means of affixing the caster assembly 22 to the leg 10 of a bed frame can be used , however , in the embodiment shown in the drawings and which is quite common , the upstanding stem 24 interfits into the opening 20 and is retrained there by a force fit . as such , the caster assembly 22 can be readily removed by the user and replaced without any special tools or equipment . turning now to fig1 b , there is shown an exploded view of a leg or support for a bed frame and illustrating the protective guard 26 assembled in accordance with the present invention . as can be seen , the protective guard 26 is , in this embodiment , shaped in the form of a sphere having an upper component 28 that is , as will be explained , interfitted with the leg 10 and a lower component 30 . each of the upper component 28 and the lower component 30 has a similarly shaped peripheral mating surface 32 and 34 , respectively , and those mating surfaces 32 , 34 interfit together to form the completed protective guard 26 when assembled . the actual mating of the upper component 28 and the lower component 30 may be facilitated by means of a flange and recess on the peripheral mating surfaces 32 and 34 , that is , there may be a recess 36 surrounding the mating surface 34 of lower component 30 that interfits with an extending flange ( not shown ) formed in the mating surface 32 of the upper component 28 so that the upper and lower components 28 and 30 securely and snugly interfit together . a specially configured opening 38 is formed in the upper surface of the upper component 28 so as to allow the leg 10 to fit into the protective guard 26 , when assembled . as can be seen , the opening 38 is comprised of an elongated slot 40 that receives and fits over the downwardly extending vertical plane 18 of the l - shaped cross member 12 and a generally rectangular opening 42 that receives and fits over the leg 10 itself . thus , by the particular shape of the opening 38 , the leg 10 and the vertical plane 18 of the cross member 12 can fit into the upper component 28 . during the assembly of the protective guard 26 to the leg 10 , therefore , the upper component 28 is fitted over the leg 10 and the vertical plane 1 i of the cross member 12 and the lower component 30 combined to form the overall protective guard 26 . the caster assembly 22 can then be affixed to the leg 10 by forcing the upstanding stem 24 up into the opening 20 to reattach the caster assembly 22 to the leg 10 . as noted , in a first assembly , the stem would normally include a plastic bushing , thereafter it may or may not include the plastic bushing depending on whether the caster assembly has been removed with or without that bushing . obviously , as a part to the present invention , the dimensions of the protective guard 26 are important . thus the overall height or vertical dimension of the protective guard 26 must be such that upstanding stem 24 can fit into and be forced into firm engagement with the opening 20 in the same manner as if the protective guard 26 were not present . in addition , it is important that the outer diameter or dimension of the protective guard 26 be relatively large so there will be sufficient protection to prevent a person from kicking or otherwise striking the leg or other nearby component of the bed frame . as illustrated in fig2 therefore , there is shown a perspective view of the completed assembly , that is , the protective guard 26 is affixed to the cross member 12 with the leg completely enveloped by the protective guard 26 and thus protective against the striking of the leg of the bed frame by a person . instead , the person will hit against the safe , smooth outer surface of the protective guard 26 and not be injured . it should be noted with respect to fig2 that the outer perimeter , or , in the case of the sphere , the outer diameter , of the protective guard 26 is obviously of sufficient size that the person subject to injury will hit the smooth outer surface of the protective guard and not a frame member of the bed frame . in addition , as will be seen , the caster assembly 22 interfits well up into the protective guard 26 by means of a large recess that can be formed in the bottom of the protective guard 26 . turning now to fig3 there is shown a side cross - sectional view of a protective guard 26 that is adapted to be held to the leg of a cross member by means of the stem 24 that , as previously explained , is fitted up into a corresponding fitting or hole in the leg so as to be retained to the leg , thereby holding the protective guard 26 in place affixed to the leg . in the embodiment of this figure , however , the protective guard 26 is a one - piece construction and thus , is simply fitted over the leg of the cross member and the caster assembly 22 fitted up into the recess 39 so as to fit snugly therein . obviously , the caster assembly 22 of fig3 is a glide , however , the one piece protective guard 26 can be used with a roller caster or other caster used with bed frames . in fig4 there is shown a side cross - sectional view of a further embodiment of the present invention wherein the protective guard 26 is a one piece construction as described with respect to fig3 however , the upstanding stem 24 is insert molded into the base 41 of the protective guard . thus , the overall protective guard 26 can be an injection molded plastic construction and the upstanding stem 24 molded into the plastic as the unit is formed , or alternatively , the protective guard 26 can be blow molded . if injection insert molded , the stem will normally be metal , while , if blow molded , the stem will generally be plastic . again , the portion of the protective guard 26 that contacts the floor may comprise rollers 43 inserted into the base of the protective guard 26 . such roller inserts are commercially available in the form of cartridges and can be force fit into holes in the bottom of the protective guard 26 or molded into the protective guard 26 during the molding process so that the bed frame is mobile and can easily be moved about the room . the rollers can be of the spherical type shown and described in copending u . s . patent application , u . s . ser . no . 09 / 519 , 725 , entitled caster assembly for a bed frame member or furniture , the disclosure of which is incorporated herein . next , in fig5 there is shown a side cross - sectional view of a protective guard 26 constructed of injection molded plastic in a one - piece component similar to the fig4 embodiment , however the bottom on the protective guard 26 is flat surface such that the bed frame is not mobile . again , however , the protective guard 26 is affixed to the cross member by interfitting of the upstanding stem 24 into an opening in the leg of the cross member . as can be seen , with the upstanding stem 24 of fig4 and 5 , the protective guard 26 may be a multi piece construction , similar to the fig2 embodiment where the protective guard 26 is comprised of two components . in the case of two components , the molded - in stem would be molded into the lower component of the overall protective guard construction . turning now to fig6 there is shown an exploded view of the preferred embodiment of the protective guard 50 of the present invention and where there is an upper component 52 and a lower component 54 , again , shown as hemispheres that are fitted together to form a spherical configuration as will be shown . in the upper surface of the upper component 52 , there is a rectangular opening 56 that is adapted to receive a bed frame leg as previously explained with reference to the prior embodiments . in addition , there is a caster assembly 58 having a stem 60 that projects upwardly into the protective guard 50 to be affixed to the bed frame leg when assembled to a bed frame . in fig7 a and 7b , there are shown , a top perspective view and a bottom perspective view of the upper component 52 where the rectangular opening 56 is formed in the upper surface of the upper component and , in fig7 b , there are a number of reinforcing ribs 60 that lead into the molded supporting receptacle 62 that is generally formed in the shape of a truncated trapezoid and which receives and supports the leg of the bed frame as will be seen . next , in fig8 a and 8b , there is a top perspective view and a bottom perspective view of the lower component 54 and , as seen , in fig8 a , there are further reinforcing ribs 64 for structural integrity and at the bottom surface of the lower component 54 , there are a number of bosses 66 having holes to allow the caster assembly ( fig6 ) to be affixed to the lower component 54 of the protective guard 50 by means such as thread forming screws . in fig9 there is a side view of the protective guard 50 of the present invention affixed in position to a bed frame and , as can be seen in this view , the protective guard 50 is located in position at the head of the bed frame , it being used for illustrative purposes . although the embodiment shown , is specific to a particular location it will be seen that a universal protective guard can be devised that would be adaptable to be used at any location of the legs of the bed frame . fig1 is a side cross sectional view of the embodiment of fig9 taken along the line 10 — 10 of fig9 and shows the side rail 68 with a cross member 70 joined thereto and a leg 72 extending downwardly from the cross member . as is conventional , the leg 72 comprises a pair of flat steel members 73 that form a generally triangular cross section and having a bottom flat surface with an opening formed therein for affixing the caster assembly 58 to the leg 72 . as can be seen , the leg 72 fits into the supporting receptacle 62 and is supported in the supporting receptacle 62 with the truncated trapezoidal configuration of the leg 72 fitting somewhat loosely into that supporting receptacle 62 . further in fig1 , the caster assembly 58 is a specially constructed caster for the preferred embodiment and comprises an upstanding stem 74 that interfits into the opening in the lower surface of the leg 72 and there is a plastic bushing 76 that is interposed between the upstanding stem 74 and the leg 72 . the caster assembly 58 comprises an upper housing 78 and a lower housing 80 that are , together affixed to the lower portion of the lower component 52 by screws 82 . contained between the upper housing 78 and the lower housing 80 are a plurality of spherical rollers 83 that are mounted so as to freely rotate therein such that the caster assembly 58 is free to move in any direction as the bed frame is moved . preferably , there are three spherical rollers . a glide 84 is removably affixed to the bottom of the caster assembly 58 to provide the function of a glide when desired by the user and the glide is adapted to be easily removed and reattached to allow the user to have the caster assembly 58 act as a roller or as a glide . a lip 85 on the upper portion of the upper housing 78 becomes sandwiched between the lower portion of the leg 72 and the flange 86 on the bushing 76 . thus , as mentioned previously , with the preferred embodiment , in order to retrofit the protective guard 50 to an already existing and set up bed frame it is necessary to remove the bushing 76 so that the leg guard 50 can be sandwiched between the flange 86 and the lower portion of the leg 72 . thus , that operation may require the need for basic tools , such as pliers . turning to fig1 , there is a perspective view of the protective guard 50 affixed to the leg 72 by having the leg 72 project downwardly into the rectangular opening 56 of the protective guard 50 . as also can be seen , there is a shield 69 that protects the ends of the side rail and the junction of the cross member and the side rail and that shield is constructed in accordance with the shield disclosed in our u . s . patent application , u . s . ser . 09 / 586 , 345 , filed on the same day as the present application and entitled bed frame shields and the disclosure of such application is incorporated herein by reference . in fig1 , there is an enlarged side cross sectional view of the means of joining the peripheral edge of the lower component 54 and the upper component 52 . as shown , there is and annular projecting rim 88 projecting outwardly from a recessed periphery of the lower component 54 that interfits into a annular recess 90 formed in the internal surface of the lower periphery of the upper component 52 . thus , to assemble the lower component 54 to the upper component 52 , the components 52 , 54 are merely snapped together without the need for tools or the like to complete the assembly of the protective guard 50 . thus , with the preferred embodiment , as shown in fig6 - 12 , the protective guard 50 can be fitted onto the leg of a bed frame and provides a protective covering for that leg to prevent injury to persons otherwise striking the leg . with the protective guard 50 , the user is protected from injury and yet there is a decorative feature to the protective guard 50 so the it performs the dual function of providing an attractive alternate to a bare bed frame leg as well as carry out a protective , safety feature to the bed frame . turning now to fig1 a - 13d , there is shown a series of different configurations of the protective guard 26 that are within the scope of the present invention . as can be seen in fig1 a , the protective guard 26 is in the shape of a sphere as illustrated in the prior figures . in fig1 b , the particular configuration of the protective guard 26 is shaped as a cube . in fig1 c , the protective guard 26 is a hexagonal configuration and in fig1 d , the protective guard 26 has a particular design on its outer peripheral surface . thus , not only does the protective guard have a utilitarian function to protect the persons from inadvertently getting injured by hitting the bed frame , but there is a decorative aspect of the present invention inasmuch as the configuration of the protective guard 26 may take on a variety of different looks . if , for example , the room within which the bed is located is decorated in a sports motif , the protective guard may be designed as some sports paraphernalia , such as a baseball , soccer ball , basketball or other item of sports equipment . obviously , there are a wide variety of configurations and designs that may be used with the present invention and the protective guard may , as explained , be installed , removed and replaced by the owner easily and conveniently without special tools by simply removing the caster assembly and installing or reinstalling the protective guard and then reconnecting the same caster assembly back into its original location . thus , the versatility of the protective guard enables the owner to have protection against injury , while at the same time , provide a wide variety of decorative enhancements available to the particular room and have the option to change those enhancements at will as the motif of the room or the taste of the occupant of the room changes . while the present invention has been set forth in terms of a specific embodiment or embodiments , it will be understood that the protective guard herein disclosed may be modified or altered by those skilled in the art to other configurations . accordingly , the invention is to be broadly construed and limited only by the scope and spirit of the claims appended hereto .