Convertible footwear
BACKGROUND OF THE INVENTION 
     Cross Reference To Related Applications 
     This application is a continuation-in-part application of application Ser. No. 866,777, filed May 23, 1986 now abandoned which was a continuation of application Ser. No. 681,844, filed Dec. 14, 1984. now abandoned. 
    
    
     The Prior Art 
     The typical person usually owns numerous items of clothing in various styles and colors. The characteristic woman, for example, generally possesses an array of dresses, skirts, blouses, sweaters, jackets and other items which are alternately worn in &#34;mix and match&#34; fashion. To complement the clothing and complete the style image, requires judicious selection of footwear. 
     Footwear tends to be a relatively expensive item of dress. Accordingly, in the usual wardrobe, the selection of apparel exceeds the available footwear. To insure the availability of an appropriate choice, the typical dresser usually limits the wardrobe to comparatively few pairs of footwear in carefully chosen basic colors and styles. 
     In view of the foregoing synopsis of a generalized enigma, the desirability of footwear with convertible style is readily appreciated. In recognition of the long standing problem, the prior art has proposed numerous proported solutions. Attention is directed to U.S. Pat. No. 4,363,177, which sets forth a specific configuration. The reference also contains a more detailed treatment of the subject and includes citations to other prior art endeavors. 
     Of particular immediate interest are the replaceable uppers. The concept is well established. Briefly, a sole is provided with a plurality of interchangeable uppers. Preferably, the sole is in a basic or neutral color. The uppers are supplied in an array of colors and designs. Accordingly, the user, at a relatively reduced cost, can have a pair of shoes which compliment the chosen apparel. 
     The prior art has not, however, provided an entirely adequate solution. As clearly pointed out in the referenced patent &#34;. . . serious questions are raised as to the robustness of the attachments and locking members for the removable elements&#34;. Additionally, the prior art has not satisfactorily accommodated the convenience of the user. 
     It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art. 
     Accordingly, it is an object of the present invention to provide improvements in convertible footwear. 
     Another object of the invention is the provision of improved engagement means for detachably securing the upper to the sole of the shoe. 
     And another object of the invention is to provide engagement means which are readily and conveniently usable. 
     Still another object of this invention is the provision of engagement means which will reliably and secureably affix an upper to a sole. 
     Yet another object of the invention is to provide means whereby the holding ability of the engagement means will be reinforced in response to a foot being inserted into the shoe. 
     Yet still another object of the instant invention is the provision of unobtrusive engagement means whereby the attachment of an upper to a sole is obscured from view. 
     And a further object of the invention is to provide engagement means in the form of a separately manufacturable clasp which can be used in connection with otherwise conventional footwear. 
     Still a further object of the invention is the provision of a clasp which is usable for securing a first component to a second component, such as the ends of a belt. 
     And still a further object of the invention is to provide an engagement means or clasp, of the above character, which is inexpensively yet durably constructed. 
     SUMMARY OF THE INVENTION 
     Briefly, to achieve the desired objects of improved convertible footwear in accordance with an embodiment of the invention, there is provided a shoe including a sole having substantially opposed edges and an upper having projecting flaps. A male element of a male/female engagement pair is carried by each flap. Female elements of the male/female engagement pair are carried by the sole. Each female element, which preferably resides within a recess formed into the sole, includes an opening in the respective edge for receiving a respective male element. 
     In accordance with a further embodiment of the invention, provided are detent means interacting between the elements of the engagement pair for selectively and detachably retaining the male element within the female element. The force exerted by the detent means for maintaining the engagement is reinforced in response to the pressure of a foot bearing upon the top surface of the sole. 
     In a more specific embodiment, the female element is in the form of a receptacle and the male element is in the form of a tab. The detent means includes an indentation carried by one of the elements and protrusion carried by the other of the elements. The indentation and the protrusion are normally retained in a mating engagement by biasing means. The biasing means is movable to a release position in response to application of a force to withdraw the male element in a direction generally parallel to the longitudinal axis of the engagement pair. It is also contemplated that a magnetic attraction may exist between the male element and the female element. 
     The engagement pair also has utility as a clasp for detachably securing a first component to a second component, such as the ends of a belt. Both elements are provided with attachment means for affixing respective ones of the components. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and further and more specific objects and advantages of the instant invention will become readily apparent to those skilled in the art from the following detailed description of preferred embodiments thereof, taken in conjunction with the drawings in which: 
     FIG. 1 is a perspective view of convertible style footwear embodying the principles of the instant invention, which for purposes of illustration is shown in the exemplary form of a readily recognizable ladies&#39; shoe; 
     FIG. 2 is an exploded perspective view of the shoe of FIG. 1; 
     FIG. 3 is an enlarged perspective view of the shoe of FIG. 1, the toe portion being removed along the line 3--3 of FIG. 1 and specifically revealing the normally obscured means in accordance with the preferred embodiment of the instant invention for securing an upper to the sole; 
     FIG. 4 is an enlarged vertical, sectional view taken at the cutting plane indicated in FIG. 1; 
     FIG. 5 is an enlarged perspective view of the male and female and elements of the male/female engagement pair seen in FIGS. 2, 3 and 4 and utilized for detachably securing the uppers to the sole, portions thereof being broken away for purposes of illustration, 
     FIG. 5A is a view generally corresponding to the view of FIG. 5 and showing the engagement pair during an initial stage of engagement; 
     FIG. 5B is a view generally corresponding to the view of FIG. 5A and showing the components thereof at a subsequent stage of engagement; 
     FIG. 5C is a view generally corresponding to the view of FIG. 5B and illustrating the male and female elements after the engagement is completed; 
     FIG. 6 is a view generally corresponding to the view of FIG. 5 and illustrating an alternate embodiment of the instant invention; 
     FIG. 6A is a view generally corresponding to the view of FIG. 6 and showing the engagement pair during an initial stage of engagement; 
     FIG. 6B is a view generally corresponding to the view of FIG. 6A and showing the components thereof at subsequent stage of engagement; 
     FIG. 6C is a view generally corresponding to the view of FIG. 6B and illustrating the male and female elements after the engagement is completed; 
     FIG. 7 is an exploded perspective view of the sole of an alternate footwear constructed in accordance with the teachings of the instant invention; 
     FIG. 8 is an exploded perspective view of yet another alternate embodiment of the instant invention; 
     FIG. 9 is a perspective view of still another embodiment of a sole for footwear embodying the principles of the instant invention; and 
     FIG. 10 is a perspective view of another alternate embodiment of a male/female engagement pair according to the instant invention as it would appear when being employed for the purpose of detachably securing a first component to a second component, such as the ends of a belt; 
     FIG. 11 is a view generally corresponding to the view of FIG. 5 and illustrating an alternate embodiment of the present invention; 
     FIG. 11A is a view generally corresponding to the view of FIG. 11 and showing the engagement pair during an initial stage of engagement; and 
     FIG. 11B is a view generally corresponding to the view of FIG. 11A and illustrating the male and female elements after engagement is completed. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning now to the drawings, in which like reference characters indicate corresponding elements throughout the several views, attention is first directed to FIG. 1 which illustrates a shoe generally designated by the reference character 20 and embodying the principles of the instant invention. Shoe 20, as is standard within the art, includes sole 22 and first and second uppers 23 and 24, respectively. 
     Sole 22 includes an upper surface 25 for receiving the foot of the wearer thereon, a bottom surface 27 for bearing upon the ground and spaced apart edges 28 and 29. The edges 28 and 29 which generally meet at the toe end 30 and heel end 32 of sole 22 are considered to be the lateral portions of sidewall 33 which extends continuously between top surface 29 and bottom surface 27. 
     First upper 23, which resides proximate toe end 30, includes flexible element 34 having extending flaps 35. Second upper 24, in general similarity to first upper 23, includes flexible element 37 and flaps defining projecting terminal end portions 38. 
     The foregoing description of shoe 20 is herein set forth for purposes of orientation and understanding in connection with the instant invention. Shoe 20, herein shown in a distinctive ladies&#39; style, is intended to be generally representative of that class of wearing apparel generally referred to as footwear. Details not specifically illustrated will be readily apparent and understood by those skilled in the art. For example, sole 20 may be constructed of such material as leather, wood or plastic. The flexible elements 24 and 37 are generally fabricated of leather, plastic, cloth or other material chosen to be both decorative and functional. 
     In accordance with the immediately preferred embodiment of the instant invention, sole 22 as seen in greater detail in FIG. 2, includes a support member 39 and a foot pad 40. Support member 39, in turn, includes lower portion 42 and upper portion 43. Lower portion 39, which carries bottom surface 27, includes upper surface 44 for receiving the under surface 45 of upper portion thereon. Over surface 47 of upper portion 43 receives foot pad 40. Lower portion 42, upper portion 43 and foot pad 40 are sandwiched together and secured in juxtaposition by gluing, sewing or other expediency conventional in the art. 
     A plurality of recesses 48 are formed in upper portion 43 of sole 22. In the immediate embodiment, each recess 48 is open in both the over and under surfaces 47 and 45, respectively, of upper portion 43. The recesses are also open in respective edges 28 and 29. Each recess 48 is sized and shaped to receive a female element 49 of a male/female engagement pair. Preferably upper portion 43 has a thickness generally corresponding to the thickness of the female elements 49. A male element 50 of the male/female engagement pair is carried by each flap 35 and 38. The male/female engagement pair will be hereinafter described in greater detail. 
     The male/female engagement pair, including female element 49 and male element 50, and the use thereof for detachably securing first and second upper 23 and 24, respectively, to sole 22 in the immediate embodiment of the invention generally designated by the reference character 20 is more clearly illustrated with reference to FIGS. 3, 4 and 5. With particular reference to FIG. 5, it is seen that female element 49 includes first and second substantially parallel sidewalls 52 and 53, respectively, held in spaced relationship by edge walls 54 and 55 and end wall 57. The several walls define a receptacle having an open end 58. Sidewall 52 is integral with or secured to edge walls 54 and 55 along a length thereof adjacent open end 58. For the remaining portion, sidewall 52 is independent of edge walls 54 and 55. Sidewall 55 is also independent of end wall 57 as indicated by the line 59. An inwardly directed protrusion 60 extends laterally across sidewall 53 proximate end wall 57. It is noted that protrusion 60 is curveaform in cross-section. 
     Male element 50, being generally rectangular in cross-section, includes top surface 62, bottom surface 63 and edges 64 and 65. Further included are first end 67 and second end 68. Recess 69 is formed into surface 63 proximate end 67. The recess, which is generally curveaform in cross-section, extends transverse of surface 63. Attachment means 70 for affixing flaps 35 or 38 are carried proximate end 68. In accordance with the immediately preferred embodiment, attachment means 70 includes a pair of spaced part lips 72 between which the flaps can be crimped, glued or otherwise secured. A shoulder 73 resides between the lips 72 and the respective surfaces 62 and 63. 
     With particular reference to FIGS. 3 and 4, it is seen that each recess 48 has a horizontal depth at least equal to the combined length of the female receptacle 49 and the lip 72. The female element 49 resides at the inner end of recess 48. Accordingly, the entire male/female engagement pair can be obscured within recess 48, as particularly illustrated in FIG. 3. 
     The surface and the edges 62, 63, 64 and 65, define a lug of the male component 50 which is receivable through the opening 58 into the receptacle of the female component 49 as best seen in FIG. 5A. The lug is receivable into the receptacle and alternately removable therefrom, in directions which are substantially parallel to the longitudinal axis of the male/female engagement pair as shown by the double arrowed line A. With further reference to FIG. 4, it is seen that the directions indicated by the double arrowed line A are substantially parallel to the top and bottom surfaces 25 and 27, respectively, of the sole 22. 
     Male element 50 is preferably fabricated of a suitable metal or plastic which provides substantial rigidity. Female element 49, a thin walled structure, may also be fabricated of a suitable metal or plastic. At least the first sidewall 52 of female element 49 is spring tempered. Protrusion 60 is matingly engageable with recess 69. Accordingly, as the insertion proceeds in the direction of arrowed line B, as seen in FIG. 5B, first sidewall 52 is deflected upwardly in the direction indicated by the arrowed line C to allow the portion adjacent first end 67 of the male element 50 to pass over protrusion 60 and effect the engagement as seen in FIG. 5C. Indentation 69, protrusion 60 and sidewall 52 function as detent means for maintaining the engagement between the female element 49 and the male element 50. Within the detent arrangement, sidewall 52 functions as biasing means to maintain the engagement between the indentation and the protrusion. 
     Foot pad 40, in accordance with standard technology, is resilient for the comfort of the foot of the wearer. As a result of the inherent resiliency, foot pad 40 is deformable within localized areas to accommodate the deflection of sidewall 52 in the direction indicated by the arrowed line C. The pressure exerted by the foot of the wearer in the direction of arrowed line D, as seen in FIG. 4, reinforces the force of the biasing means for maintaining the engagement between the male element and the female element. It is also apparent, that since the elements of the male/female engagement pair can be disengaged only as a result of the application to components of forces in opposite directions along a line which is substantially parallel to the surface 25, the upward pressure of the foot against either upper in a direction which is perpendicular to the surface 25 as indicated by the arrowed line E does not tend to separate the upper from the sole. 
     FIG. 6 illustrates an alternate male/female engagement pair which is usable in connection with the previously described convertible style shoe. 
     In general similarity to the previously described engagement pair, the immediate engagement pair includes female element 79 and male element 80. In further similarity, female element 79 includes first sidewall 82, second sidewall 83, edge walls 84 and 85, and end wall 87 which define a receptacle having an open end 88. First sidewall 82 is secured to the edge walls 84 and 85 for a distance extending from open end 88 and is separated from the edge walls and from the end wall 87 as shown by the line 89. Alternate to the previous embodiment, however, protrusion 90 is carried by first end wall 82. 
     Male element 80, again in similarity to the previously described counterpart, includes top surface 92, bottom surface 93, edges 94 and 95, and first and second ends 97 and 98. Indentation 99, for mating engagement with protrusion 90, is carried by top surface 92. For reasons previously described, attachment means 100 including lips 102 are carried proximate second end 98 and separated from the surfaces 92 and 93 by shoulders 103. As may be appreciated by those skilled in the art, male element 80 is previously described male element 50 which has been reoriented by rotating 180 degrees. 
     Top surface 92, bottom surface 93 and edges 94 and 95 define a lug 104 which is receivable, and alternately removable, into the receptacle of the female element in directions indicated by the double arrowed line F which is substantially parallel to the longitudinal axis of the engagement pair as seen in FIG. 6A. With further reference to FIGS. 6B and 6C, it is seen that the function and operation of the immediate engagement pair is analogous to the previously described engagement pair. 
     FIG. 11 illustrates an alternate male/female engagement pair which is usable in connection with the previously described convertible style shoe. 
     In general similarity to the previously described engagement pair, the engagement pair of FIG. 11 includes a female element 180 and a male element 181. Female element 180 includes a first sidewall 182, a second sidewall 183, edgewalls 184 and 185, and end wall 186, all of which define a receptacle having an open end. 
     Male element 80 includes a top surface 188, bottom surface 189, edge 190 and 191, and first and second ends 192 and 193. Again, for reasons previously described, attachment means 100 including lips 102 are carried proximate second end 193 and separated from surfaces 188 and 189 by shoulders 103. 
     Top surface 188, bottom surface 189, and edges 190, 191 and 192 define a lug 194 which is receivably, and alternately removable, into the receptacle of a female element in the directions indicated by the double arrowed line which is substantially parallel to the longitudinal axis of the engagement pair as is seen in FIG. 11A. With further reference to FIG. 11B, it is seen that the functional operation of the engagement pair is analogous to the previously described engagement pair with the following exception. Each of the male and female elements are made of a magnetic or ferro-magnetic material (e.g. metal or plastic impregnated with ferro-magnetic material) such that the magnetic attraction between the male and female members will favor the fully inserted position shown in FIG. 11B. The magnetic forces urging the male and female elements together in a fully inserted relationship such as shown in FIG. 11B must be overcome by pulling the female member out of the male member in order to separate the male and female members. 
     FIG. 7 illustrates an alternate convertible style shoe, generally designated by the reference character 107, embodying the principles of the instant invention. The immediate embodiment includes support member 108 including the previously described lower portion 42. In further similarity to the previously described embodiment, the immediate embodiment also includes foot pad 40. 
     The intermediate member, the upper portion 109 of support member 108, represents a modification of the previously described upper portion 43. The instant upper member 109 includes upper surface 110 which receives foot pad 40 thereon, under surface 112 which is bonded to the upper surface 44 of the lower portion 42, and a continuous sidewall 113 which is shaped so as to form spaced apart opposed edges 114 and 115. A plurality of recesses 117 are formed into upper member 109 from the top surface 110 and the sidewall 113. Each recess 117 is sized and shaped to receive a female element 118. The female element 118 is generically representative of the previously described female elements 49 and 79. 
     The sole described in connection with FIG. 7 is assemblable with the uppers 23 and 24 illustrated in FIGS. 1 through 4. In all other details not specifically set forth, shoe 107 is analogous to the previously described shoe 20. 
     Yet another embodiment of a convertible style shoe, generally designated by the reference character 120, is illustrated in FIG. 8. In common with the previously described embodiments, shoe 120 shares the lower portion 42 of the support member 39. In contrast thereto, however, the upper portion of the support member and foot pad appear as an integral unit shown as alternate foot pad 122 having top surface 123, under surface 124 and continuous sidewall 125 which is shaped to provide a pair of opposed edges 127 and 128. 
     Being of substantially greater thickness than the previously described foot pad, foot pad 122 has a plurality of recesses 129 formed therein. The recesses which are formed into the under surface 124 are also exposed along respective edges 127 and 128. Each recess is sized and shaped to receive a female element 118 therein. In other aspects not specifically described, the immediate embodiment is generally similar to the previously described embodiment including the attachment of the uppers 23 and 24. 
     With respect to FIG. 9 there is seen yet another convertible style shoe of the instant invention generally designated by the reference character 130. Included in the immediate embodiment is an alternate support member 132 and previously described foot pad 40. Support member 132 includes bottom surface 133, upper surface 134 and opposed edges 135 and 137 which re portions of continuous sidewall 138. A plurality of recesses 139 are molded, cut or otherwise formed into support member 132 to be exposed in the upper surface 134 and the sidewall 138. As will be appreciated by those skilled in the art, a female element 118 is receivable within each recess 139, foot pad 40 is bonded to surface 134, and uppers 23 and 24 may be detachably affixed thereto to form a shoe having a general appearance of the footwear seen in FIG. 1. 
     The male/female engagement pair of the instant invention has further utility as a clasp for detachably securing a first component to a second component. Reference is now made to FIG. 10 which illustrates a belt, generally designated by the reference character 140, having first and second terminal end portions 142 and 143. A clasp, generally designated by the reference character 144 and embodying the principles of the instant invention, detachably secures first end portion 142 to second end portion 143. Clasp 144 being an alternate embodiment of the previously described male/female engagement pairs includes male element 145 and female element 146. 
     Male element 145 includes lug 147 having first end 148 and second end 149. Indentation 150 is formed in lug 147 proximate first end 148. Engagement means 152 for affixing end portion 143 are carried proximate second end 149. In the immediate embodiment, the engagement means includes a pair of spaced apart lips 153 for receiving the end portion 143 therebetween and a pair of rivets 154 which extend through the lips and the end portion 143. 
     Female element 146, in general analogy to female elements 49 and 79, includes first and second sidewalls 155 and 157, respectively, edges 158 and 159 and first and second open ends 160 and 162, respectively. A portion of second sidewall 155 is secured to edges 158 and 159 along a length adjacent each open end 160 and 162 and is severed from the edges 158 and 159 along an intermediate length by a slit as represented by the line 163. While only one line 163, appearing at the intersection of sidewall 155 and edge 159, is seen in the immediate illustration, it will be appreciated that a corresponding slit appears between the sidewall 155 and the edge 158. For purposes of reference, the portion of sidewall 155 intermediate slits 163 is designated as the portion 164. Transverse inwardly directed protrusion 165 is carried by sidewall 157 at a location substantially opposite portion 164. 
     As in the previously described embodiments, lug 147 is removable through open end 160 into the receptacle formed by the several sidewalls and edges of female element 146. Indentation 150 is matingly engageable with protrusion 165. Portion 164 will flex sufficiently to accommodate the engagement. Further, portion 164 functions as biasing means in cooperation with indentation 150 and protrusion 164 as detent means for maintaining the detachable engagement between the male and female elements. As will be appreciated by those skilled in the art, protrusion 165 may be carried by portion 164. 
     First end portion 142 of belt 140 is receivable within female element 146 through open end 162. Additional rivets 154 extend through the sidewalls 155 and 157 and end portion 142. Accordingly, the sidewalls 155 and 157 and rivets 154 function as engagement means for affixing first end portion 142 to female element 146. When the belt 140 with clasp 144 of the instant invention is worn about the torso of a person in accordance with conventional practice, with sidewall 155 inwardly, the pressure of the torso against portion 164 reinforces the biasing means to further insure disengagement between the male and female components in a matter analogous to the pressure of the foot as previously described. 
     Various changes and modifications to the embodiments herein chosen for purposes of illustration will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention, they are intended to be included within the scope thereof which is assessed only by a fair interpertation of the following claims. 
     Having fully described the instant invention and alternated embodiments thereof in such clear and concise terms as to enable those skilled in th art to understand and practice the same, the invention claimed is: