Patent Publication Number: US-6711835-B1

Title: Shoe and replaceable heel

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to the field of footwear, and more specifically to replaceable and interchangeable shoe heels. 
     2. Background Art 
     Some people carry an extra pair or two of shoes in their bags just so they can change shoe height or shoe style on the go. But because shoes are heavy and take up significant space, carrying them can be very inconvenient. A solution known in the art is the interchangeable, removable heel. Interchangeable, removable heels, or “replaceable heels,” help people avoid cluttering their bags with shoes. 
     For example, if a person were headed out for the evening, she may want to wear flats on the street, and then change into high heels at the soirée. Replaceable heels enable the person to make that change without carrying a full extra pair of shoes. The person carries just the replaceable heels, which can be connected and disconnected from a single pair of shoes. Upon arrival at the soirée, the person removes the flat heels and attaches the high heels, placing the flat heels lightly in her bag. 
     The problem with known replaceable heels is that they are of complicated design and construction that renders their implementation too expensive and burdensome. Further, some replaceable heels can be attached or removed only with portable tools. There is a need for a simple, inexpensive replaceable heel and shoe construction that is simple to manufacture and easy to use without tools. 
     There are also undesirable side effects of using replaceable heels. When the heel on a rigid shoe is raised, the sole may leave the ground at a point near the ball of the foot (the “ball area” of the sole). A shoe not designed to compensate for adjustable heels will experience wear and tear caused by compressing the inner sole and stretching the outer sole as pressure is placed on the shoe by the ball of the foot. The shoe may even collapse under the weight of the wearer. What is needed is a shoe for replaceable heels with a sole that can flex with the differing stresses of heels of various heights while keeping the ball of the foot comfortably on the ground. 
     Also, using replaceable heels can crumple or over-extend a shoe&#39;s upper (the top part of a shoe above the sole). The taller the heels, the less the angle between the toes and the rest of the foot. When taller heels are used, the shoe&#39;s upper is forced into a more compact angle, which crumples the surface and negatively affects the shoe&#39;s appearance. When shorter heels are used, either the shoe&#39;s upper is stretched and potentially damaged or the upper refuses to stretch and the wearer&#39;s toes curl uncomfortably upwards. What is needed is a shoe with an upper that works in conjunction with replaceable heels to compress and extend as needed when heels are changed. 
     Finally, replaceable heels of the prior art have a tendency to come off during wear. Solutions to this conundrum have again involved intricate mechanisms that are expensive to manufacture. What is needed is simple mechanism for preventing the replaceable heel from coming off during wear. 
     DISCLOSURE OF INVENTION 
     The present invention provides for a shoe ( 100 ) and a replaceable heel ( 500 ) of simple design, manufacture and use. An angularly-bent metal plate ( 200 ) is attached to the base heel ( 120 ) of the shoe ( 100 ). A replaceable heel ( 500 ) with a slot ( 520 ) in its front is easily slid on or off the metal plate ( 200 ) without tools. This combined mechanism of the single bent plate ( 200 ) and the replaceable heel ( 500 ) with the simple slot ( 520 ) in its front is inexpensive to manufacture and easy to use without need for tools. The plate ( 200 ) is preferably elastic enough to be bent away from the sole ( 120 ) to attach the heel ( 500 ) and, once the heel ( 500 ) is attached, to attempt to return to its original position, thereby gripping the heel ( 500 ) against the sole ( 120 ). 
     In one embodiment, the sole ( 140 ) of the shoe of the present invention has one or more gaps ( 142 ,  146 ) to enable it to flex as heel height is changed. In one embodiment, the shoe&#39;s upper ( 160 ) has a flexible strip ( 180 ) to curtail the strain on the upper ( 160 ) caused by changing heel heights. In one embodiment, a sliding restraint ( 130 ) at the back of the shoe ( 100 ) prevents the heel ( 500 ) from slipping off during wear. 
     The features and advantages described in this summary and the following detailed description are not all-inclusive, and particularly, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims hereof. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The figures depict a preferred embodiment of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein. 
     FIG. 1 is an illustration of a body shoe  100  with a plate  200  attached to a heel base  120 . 
     FIG. 2 is an illustration of a plate  200  that may be attached to a heel base of a shoe. 
     FIG. 3 illustrates attaching a replaceable heel  500  to a shoe  100  with a plate  200 . 
     FIG. 4 is an illustration of a cross section of a shoe  100  with a replaceable heel  500  attached, the cross section illustrating the way the plate  200  applies upward pressure to hold the heel  500  firmly to the shoe  100 . 
     FIG. 5 illustrates a replaceable heel  500 . 
     FIG. 6 is an illustration of a sliding restraint  130  on the back of a shoe  100 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A shoe construction with a replaceable heel according to an embodiment of the present invention has three components: a body shoe  100 , as illustrated in FIG. 1; a plate  200  as illustrated in FIG. 2; and a replaceable heel  500  as illustrated in FIG.  5 . 
     The Body Shoe 
     FIG. 1 illustrates the body shoe  100  having an upper  160 , which is attached to a sole  140 , which is in turn attached to a heel base  120  of height  127 . The body shoe  100  may be understood as any footwear including but not limited to a dress shoe, tennis shoe, casual wear, sandal, slipper, boot, skate, snowshoe, or thong. The upper may be of any style or material including but not limited to leather, rubber, straps, cloth, canvas or a combination thereof. The sole may be of any style or material including but not limited to leather, plastic, rope, rubber, or a combination thereof. In a preferred embodiment, the sole is a combination of leather and rubber. The heel base  120 , preferably but not necessarily of the same material as the sole, has a front surface  122  and a rear surface  124 , both substantially perpendicular to a bottom surface  123 . The rear surface  124  may be flat or curved. 
     The Sole 
     In one embodiment, the sole  140  contains gaps that enable it to withstand stress produced by different sized heels. As seen in FIG. 1, sole  140  is made of three layers: inner sole  141 , middle sole  143 , and outer sole  145 . Middle sole  143  is preferably made of flexible, water resistant material, such as a sheet of leather or rubber, and is interjacent to inner sole  141  and outer sole  145 . Inner sole  141  and outer sole  145  are affixed to middle sole  143  and can be made of the same or different materials, including but not limited to leather, plastic, rope, rubber, or a combination thereof. 
     Both or either of inner sole  141  and outer sole  145  preferably have one or more gaps  142 ,  146 , positioned so that the sole  140  may flex as the heel height is raised or lowered. Specifically, as higher heels are attached, inner gaps  142  contract and outer gaps  146  expand; as lower heels are attached, inner gaps  142  expand and outer gaps  146  contract. Thus the ball of the shoe can remain flat on the ground despite the changing height of the heel. 
     A preferred embodiment features a single ⅛″ inner gap  142  and a single ⅛″ outer gap  146 , both proximal to the ball area of the sole  140 , though multiple gaps of various sizes may be incorporated. In another embodiment, inner and outer gaps are located proximate to the front  122  of the heel base  120 , another area of the sole that takes on significant stress when the height of the heel is altered. In another embodiment, the middle sole  143  and just one of the inner sole  141  or the outer sole  145  is used. It will be further recognized that additional layers of sole can be added, such as a thin layer above inner sole  141  to protect from pinching the foot. 
     A Flexible Upper 
     As illustrated in FIG. 1, in one embodiment, a portion of the upper  160  is formed with a flexible strip  180  in order to provide flexing to account for different height heels and prevent crinkling and folding at the bend of the toes (the portion of the upper adjacent to the metatarsal phalangeal joints). The flexible strip  180  spans the top of the shoe at or near the bend of the toes, and wraps around the upper (or spans at least a portion of the way across the upper from the inside to the outside of the foot). The strip  180  provides flexibility on the top of the body shoe  100 . As higher or lower heels are attached, the flexible strip  180  accommodates the changes at the bend of the toe of the body shoe  100 . The flexible strip may be of any flexible material, and may incorporate some degree of elasticity. In a preferred embodiment, the flexible strip is of a fashionable color and material. 
     The Plate 
     To grip a replaceable heel, an angled plate  200  is attached to the body shoe  100 , preferably at a point adjacent to the front surface  122  of heel base  120 . The plate  200  has a front portion  210  and a rear portion  220 . The front portion  210  preferably extends substantially perpendicular to the sole  140  and extends beyond the heel base  120  approximately ½ inch  570 . The rear portion  220  extends from the end of the front portion  210  towards the back of the shoe. The rear portion  220  is generally perpendicular to the front portion  210  and parallel to the sole  140 . The rear portion  220  preferably has a slight angle towards the sole  140  in order to form a gripping relationship with a replaceable heel. 
     FIG. 2 illustrates further details of the plate  200 . According to one embodiment, the plate  200  has a front portion  210  of height  270  and a rear portion  220  of width  250  and depth  260 . Front portion  210  and rear portion  220  adjoin at a angle  285  of less than 90 degrees. The front portion  210  of the plate is preferably attached to the front surface  122  of the heel base  120 . In a preferred embodiment, the front portion  210  of the plate includes one or more apertures  230  and is attached to the front surface  122  of the heel base  120  by screws, bolts, pins, anchors, staples, nails, rivets, etc. (generally referred to as “pointed platefixing means”) extending through the apertures  230 , or by glue, stitches, ties, solder, heat, fusing, etc. (generally referred to, with the pointed platefixing means, as “platefixing means”). 
     Plate  200  is preferably made of metal, but may be of any material or combination of materials that (i) can be bent in manufacturing (for example, when heated) to stay at a specified angle, (ii) can flex with the application of force directed substantially perpendicular to the plane of the sole and away from the plate&#39;s original position as needed by a wearer to enable the attaching or detaching of a replaceable heel, and (iii) is elastic enough to exert force back toward the shoe in an attempt to recover its original position when so flexed to grip the replaceable heel in place. Plate  200  is preferably less than ⅛″ thick and in one preferred embodiment is less than {fraction (1/16)}″ thick. 
     The Replaceable Heel 
     FIG. 5 illustrates a detailed view of a replaceable heel manufactured according to a preferred construction. Replaceable heel  500  is preferably shaped as a rectangle with a convex curve in place of one side (the rear side). Heel  500  has a slot  520  at the front side (opposite the rear side) having a slot width  550  of preferably at least one inch and a slot depth  560  (running toward the rear side) of preferably at least 1.5 inches. Comparing FIG. 5 to FIG. 2, slot width  550  is preferably slightly wider than plate width  250 , and slot depth  560  is preferably slightly deeper than plate depth  260 , so that plate rear portion  220  can fit inside slot  520 . 
     In a preferred embodiment, to construct a replaceable heel  500  with slot  520 , the replaceable heel  500  is composed of three solid sections. Section A  501  of the replaceable heel, the middle section, is roughly “U”-shaped and preferably just slightly thicker than plate  200 . Section A  501  defines the sides of the slot  520 . Section C  503  is preferably shaped as a rectangle with a convex curve in place of its rear side (the side towards the rear of the shoe, which coincides with the curve of the “U” in section A). Section C  503  defines the top of the slot and is preferably but not necessarily solid and approximately ⅜″ thick. The top of section B  502  defines the bottom of the slot and is preferably shaped as a rectangle with a convex curve in place of its rear side. The bottom of section B  502  is the section of the heel that comes in contact with the ground or other surface. Section B  502  may be of any shape (such as but not limited to tapered, stacked, western, pump, spiked or stiletto), any height  530  (from ⅛″ to 6″ tall), and any feature or material (including but not limited to enameled, feathered, leather, wood, rubber, alligator, shock absorbing, roller, or tap). 
     The entire replaceable heel  500  may likewise be of any material or combination of materials. Such materials include but are not limited to rubber, plastic, wood, metal, and a combination thereof. Those skilled in the art will recognize that the replaceable heel with its slot  520  may be constructed by any means including but not limited to affixing sections one on top of the other, molding, carving, casting, or extruding. 
     Attaching the Heel 
     FIG. 3 illustrates attaching a replaceable heel  500  to a shoe with a plate  200  attached to its heel base  120 . Plate rear portion  220 , when flexed toward a perpendicular posture relative to plate front portion, preferably lines up with slot  520  to enable the plate  200  to be slidably inserted into the replaceable heel  500 . 
     The plate rear portion  220  is slid into slot  520 , which in turn snuggly sheaths the portion. When so attached, slot  520  runs parallel to bottom surface  123  of heel base  120 . Two forces, one from the shoe and one from the wearer, preferably cooperate to keep the replaceable heel  500  from sliding off of the plate  200 : the friction caused by the upwards force of the plate rear portion  220  on the top of the inside of the slot  520 , and the forward force exerted on the heel  500  with every step taken by the Wearer of the shoe. Attaching and detaching a heel  500  from body shoe  100  takes just seconds, and no tools are needed. In a preferred embodiment, the replaceable heel  500  and the heel base  120  are designed to look as one single heel when the replaceable heel is attached. 
     FIG. 4 illustrates a cross section of a shoe with a replaceable heel attached, the cross section illustrating the way the plate  200  applies upward pressure to hold the attached heel firmly to the shoe. Plate rear portion  220  can be seen extending into slot  520  of replaceable heel  500 . The plate&#39;s elasticity in combination with its angle  285  of less than 90 degrees advantageously allows the plate rear portion  220  to exert upwards pressure toward heel base  120  to grip the top of the inside of the slot  520  to hold the replaceable heel  500  firmly in place on the shoe  100 . 
     The Sliding Restraint 
     In one embodiment, as illustrated in FIG. 6, a sliding restraint  130  supplies a third force to further ensure that the replaceable heel stays in place. The restraint  130  is preferably attached to the rear of the heel base  120 . In one embodiment, the restraint  130  utilizes a key and keeper construction. A key  129 , such as an I-beam or a dowel with bulbs on its top and bottom ends, is contained loosely by a roughly cylindrical or roughly U-shaped keeper  128  so as to enable upwards and downwards sliding of the key through the keeper  128 . The keeper  128  is preferably affixed to the heel base  120 . The keeper  128  is preferably long enough vertically or secured well enough to prevent the replaceable heel  500  from treating the key  129  as a lever to remove the keeper  128  from the heel base. 
     In use, the key  129  of the sliding restraint  130  slides down over the back end of the replaceable heel  500 , and locks the heel into place so that it cannot slide backwards off of plate  200 . When the shoe is worn, the sliding restraint  130  is preferably held in this securing position by the force of gravity. To remove the shoe, the wearer need merely slide the restraint upwards or turn the shoe upside-down before pulling the heel off of the plate. In an alternative embodiment, sliding restraint  130  may lock into place using mechanisms well known in the art. 
     The disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.