Patent application title: SHOE SOLE AND INTERCHANGEABLE HEEL
Chang-Yen Tsai (Lincoln Park, NJ, US)
BALLET MAKERS, INC.
IPC8 Class: AA43B1337FI
Class name: Boots, shoes, and leggings interfitted sole and heel
Publication date: 2015-04-02
Patent application number: 20150089833
A shoe sole and heel assembly includes a sole, an interchangeable heel
removably connected with the sole, and at least one locking device for
fixing the heel to the sole. The sole includes a wall extending from the
heel area of the lower surface of the sole to define a cavity. The inner
surface of the wall contains a channel. The heel includes a track
extending from the side and rear portions of the heel. The heel is
arranged adjacent to the sole with the heel track entering the sole
channel. As the heel is displaced rearwardly, the track enters the
channel of the sole and prevents vertical and lateral movement of the
heel relative to the sole. A latch on the lower surface of the sole
engages a notch on the upper surface of the heel to prevent longitudinal
displacement of the heel. The sole and heel contain aligned threaded
openings for receiving screws to secure the heel to the sole.
1. A shoe sole and heel assembly, comprising (a) a sole including an
upper surface, a lower surface, a toe area, a heel area, and a wall
extending from said lower surface about the perimeter of said heel area
to define a cavity in said heel area; (b) a heel for connection with said
sole, said heel having an upper surface, a lower surface, and side walls;
and (c) a connection assembly for removably connecting said heel with
said sole, said connection assembly including i. a projection extending
from one of an inner surface of said sole cavity wall or an external
surface of said heel; ii. a channel arranged in one of an external
surface of said heel or an inner surface of said cavity wall for
receiving said track when said heel is connected with said sole; and iii.
at least one locking device for fixing said heel to said sole.
2. A shoe sole and heel assembly as defined in claim 1, wherein said locking device includes (a) a latch connected with said lower surface of said sole; and (b) said heel upper surface including a notch for receiving said latch whereby when said latch engages said notch, said heel is prevented from moving relative to said sole.
3. A shoe sole and heel assembly as defined in claim 1, wherein said locking device further comprises at least one screw passing through aligned threaded openings in said heel and said sole for further fixing said heel with said sole.
4. A shoe sole and heel assembly as defined in claim 1, wherein said locking device includes (a) a latch connected with said lower surface of said sole; (b) said heel upper surface including a notch for receiving said latch whereby when said latch engages said notch, said heel is prevented from moving relative to said sole; and (c) at least one screw passing through aligned threaded openings in said heel and said sole for further fixing said heel with said sole.
5. A shoe sole and heel assembly as defined in claim 1, and further comprising a percussive tap connected with a lower surface of said heel.
6. A shoe sole and heel assembly as defined in claim 1, wherein said sole comprises a split sole including (a) a toe portion; (b) a heel portion; and (c) at least one support band connecting said sole and heel portions.
7. A shoe sole and heel assembly as defined in claim 1, wherein said heel is hollow.
8. A heel for removable connection with a shoe sole, said heel comprising (a) an upper surface, a lower surface and side walls; (b) a connection assembly for removably connecting said heel with the shoe sole, said connection assembly includes i. a projection extending from an external surface of said heel, whereby said projection engages with a channel arranged on a shoe sole; and ii. at least one locking device for fixing said heel to a shoe sole.
9. A heel as defined in claim 8, wherein said locking device includes a notch for receiving a latch arranged on a shoe sole.
10. A heel as defined in claim 8, wherein said locking device includes at least one screw passing through aligned threaded openings in said heel and a shoe sole.
11. A heel as defined in claim 8, wherein said locking device includes (a) a notch for receiving a latch arranged on a shoe sole; and (b) at least one screw passing through aligned threaded openings in said heel and a shoe sole
12. A heel as defined in claim 8, wherein said heel is hollow.
13. A heel as defined in claim 8, and further comprising a percussive tap connected with a lower surface of said heel.
BACKGROUND OF THE INVENTION
 In tap dancing, a dancer uses a series of percussive foot movements and placements to create sound. The sounds generated by the dancer depend on several variables including technique, weight placed on the foot, force exerted through the foot, type of shoe used, material of taps used, and other variables relating to the shoe heel, including but not limited to heel height and density. All of these variables can be modified in some way, technique can be learned, and weight distribution or force can be controlled by the dancer. The greater problem to solve lies in the shoes. While there are many brands and styles of tap shoes, dancers either have to buy multiple pairs of tap shoes in order to produce a variety of sounds for performances, or they have to physically alter the shoes to create the desired weight to sound ratio. Neither of these options allow for the dancer to have one pair of shoes that can be quickly and safely altered as desired.
 The present invention relates to a replaceable heel and to a three part shoe sole and heel assembly which allows a dancer to have a single shoe and one or more interchangeable heels without changing the dance technique or heel height or risking injury to the dancer. Such interchangeable heels can have variations that affect the percussive quality, the appearance of a shoe, or both. Variations can include heel material or visual or auditory components that would be desirable to a tap dancer. Further, by utilizing a three part sole and heel assembly, an interchangeable heel is secured in such a way that is it stable and does not negatively impact a dancer's balance, body mechanics, technique, or performance.
BRIEF DESCRIPTION OF THE PRIOR ART
 Existing taps do not offer dancers the option of sound and weight modification to adjust or enhance a performance. Current industry methods for adding weight to the heel of a tap shoe (to adjust the percussive quality), as well as aftermarket modifications made by a dancer, may produce both an immediate safety risk as well as long term stress related injury. The current industry preferred method of adding additional weight to a tap shoe heel is to layer leather to achieve greater density and weight. While this method is satisfactory, it produces two potentially undesirable problems. First, additional layers of leather add height to the shoe, and second, layered heel leather can delaminate.
 By changing the height of the heel to the extent necessary to achieve the desired sound, a dancer is forced into postures that are potentially dangerous. To compensate for the additional height, improper technique and body mechanics are used by a dancer, impacting both a dancer's balance and executed performance which over extended periods can lead to injury.
 Delamination of the shoe heel is a form of structural breakdown which occurs when the many glued, or otherwise secured layers of a heel pull apart and begin to separate at the layered attachment points. This creates another safety issue for a dancer as the shoe heel can literally pull apart while dancing. Additionally, the layers of secured leather can add up to four pounds of weight to the heel, leading to stress related injuries from improper execution of dancing techniques.
 Alternatively, the percussive effect of a tap shoe can be altered using home-made, aftermarket methods to increase the weight of the shoe heel. To achieve this, weight is physically added to dance shoes. Over time and with use, such alterations threaten the structural integrity of the shoe, leading to premature breakdown of the shoe. Further, potential injury can result as a dancer must adjust the technique used by overcompensating for the additional weight, and negatively impacting the aesthetic of the performance. Still further, if the added weight shifts during execution of dancing technique, improper landing or completion of the technique can result in injury.
 The present invention was developed in order to overcome these and other drawbacks of prior dance shoes and more particularly tap shoes by providing a three part sole and interchangeable heel assembly that includes redundancy in the event of failure of any the component parts.
SUMMARY OF THE INVENTION
 Accordingly, it is the primary object of the invention to provide a three part dance shoe sole and heel assembly which allows a dancer to interchange a shoe heel, thereby allowing the dancer to specifically control for impact and vibration without changing dance technique, changing heel height, or risking injury to the dancer.
 The assembly includes a sole having upper and lower surfaces, toe and heel areas and a wall extending about the perimeter of the heel area to define a cavity in the heel area. The assembly also includes a heel having upper and lower surfaces, side walls and anterior and posterior portions. To connect the assembly, a track which projects outwardly from the upper posterior portion of the heel engages a channel arranged on the inner surface of the cavity wall. Once the heel track is fully arranged within the sole channel, at least one locking device fixes the heel to the sole. Locking devices include a latch and notch assembly on the sole and heel and one or more screws. With the heel track arranged in the sole channel, the latch and notch assembly and the crew fasteners then prevent the heel from moving relative to the sole, thereby reducing the likelihood of injury to a dancer due to incorrect execution of dancing technique or structural failure of the shoe.
 The invention also relates to an interchangeable heel. By substituting different heels, a dancer uses a single pair of shoes, but alters the percussive or aesthetic characteristics of the shoe heel.
BRIEF DESCRIPTION OF THE FIGURES
 Other objects and advantages of the invention will become apparent from a study of the following specification when viewed in the light of the accompanying drawing, in which:
 FIGS. 1 and 2 are top and bottom perspective views, respectively, of the shoe sole according to the invention;
 FIGS. 3, 4, and 5 are top, bottom, and side plan views, respectively, of the shoe sole of FIG. 1;
 FIGS. 6 and 7 are front and rear plan views, respectively, of the shoe sole;
 FIG. 8 is a sectional view of the shoe sole heal area taken along line 8-8 of FIG. 3;
 FIG. 9 is a sectional view of the shoe sole toe area taken along line 9-9 of FIG. 4;
 FIG. 10 is a sectional view of the shoe sole taken along line 10-10 of FIG. 7; and
 FIGS. 11 and 12 are exploded top and bottom perspective views, respectively, of the shoe heel and tap according to the invention.
 With reference to FIGS. 1-10, the dance shoe sole 2 according to the invention will be described. The sole includes an upper surface 4 for receiving an upper (not shown) of the dance shoe. The sole 2 is constructed of any suitable material, including but not limited to leather, suede, rubber, thermoplastic polyurethane, synthetic plastics, or polyurethane.
 As shown in FIGS. 2 and 4, the lower surface 6 of the sole 2 has a toe area 8 with which is connected a percussive tap (not shown) and a heel area 12 including a wall 14 extending from the lower surface 6 about the perimeter of the heel area 12 to define a cavity 16 in the heel area. The heel area 12 also includes one or more locking mechanisms for removably connecting a heel with the sole. As will be developed in greater detail below, these include a channel 18 arranged in the inner surface of the wall 14, a latch assembly 20 and one or more threaded openings 22 for receiving one or more screws (not shown).
 Referring now to FIGS. 11 and 12, the removable heel 24 will now be described. The heel 24 may be solid or hollow. According to a preferred embodiment, the heel is hollow. The heel may be constructed of any suitable material including but not limited to aluminum or any other metal, wood, thermoplastic polyurethane, acrylic, leather, suede, rubber, plexi-glass, synthetic plastics, polyurethane, and ethylene vinyl acetate. The heel is fabricated by molding, machining, sculpting, stacking, carving, or rapid proto-typing or any other known method.
 The heel 24 has an upper surface 26, side walls 28 and anterior 30 and posterior portions 32. A track 34 projects outwardly from the upper posterior portion 32 of the heel. At the upper anterior portion 30 of the heel, a notch 36 is provided which engages the latch 20 of the sole as will be developed below. The heel also contains a plurality of openings 38. As best shown in FIG. 12, a tap 40 is connected with a bottom surface of the heel via screws 42 which pass through openings 44 in the tap and into threaded openings 46 in the heel.
 In order to connect the heel 24 with the sole 2, the posterior position 32 of the heel is inserted into the cavity 16 in the heel area 12 of the sole. More particularly, the heel track 34 engages the sole channel 18 to align and connect the heel with the sole. The shoe sole and heel combination provides a center balanced medial to lateral fit and the channel and track connection prevents the heel from shifting vertically or laterally with respect to the sole.
 When the heel track is completely arranged in the sole channel in the heel area of the sole, the latch 20 of the sole engages the notch 36 of the heel. The latch 20 is preferably formed of a rigid material such as metal or synthetic plastic which may be deflected from its natural position. Accordingly, as the heel is connected with the sole, the notch deflects the latch until the notch has passed by the latch which then returns to its natural position. The engagement of the latch 20 and notch 36 prevents longitudinal movement of the heel relative to the sole.
 With the heel locked in place, the openings in the heel 38 are aligned with the threaded openings 22 of the sole. To complete the three part assembly of the heel 24 and sole 2, screws 48 are inserted into the sole openings from the upper surface 4 of the sole and into the heel openings and tightened to secure the heel to the sole. The screw connection secures the heel to the sole and prevents any displacement of the heel relative to the sole. In order to disassemble the heel from the sole, the connection process is reversed. The screws 48 are first withdrawn from the heel and sole assembly. Next, the latch 20 is depressed so that it is released from the notch 30 in the heel. Then the heel is slid relative to the sole until the track 34 on the heel completely exits the channel 18 in the sole. The heel is thus disconnected from the sole. This allows a different heel to be substituted, thereby providing the shoe with different percussive or aesthetic characteristics.
 While the invention has been described with reference to a tap shoe, it has applicability to other types of dance shoes, such as ballroom or character shoes.
 While the preferred forms and embodiments have been illustrated and described, it will become apparent to those of ordinary skill in the art that various changes and modifications may be made without deviating from the inventive concepts set forth above.
Patent applications by Chang-Yen Tsai, Lincoln Park, NJ US
Patent applications by BALLET MAKERS, INC.