Footwear with expanded thermoplastic beads in the footbed
Footwear (e.g., shoes, sandals, boots, etc.) is constructed with small beads stuffed into the footbed, so that can the beads can shift about due to pressure on the footbed by the user's foot during normal use. Preferably, the beads are made of expanded polystyrene, and have an average diameter between about two thirds and about one mm. The resulting footwear is very comfortable. In some sandal embodiments, the straps are also stuffed with the same type of beads
The present invention relates to footwear such as shoes, sandals, and insoles. Due to the well known nature of these items, a detailed description of the prior art is unnecessary.
SUMMARY OF THE INVENTIONAt least one portion of the footwear (e.g., the footbed) is filled with small beads that can shift about during normal use. In some preferred embodiments, the beads are made of expanded thermoplastic such as expanded polystyrene.
BRIEF DESCRIPTION OF THE DRAWINGS
The
The filling 10 is preferably made of expanded thermoplastic beads (ETBs) that are roughly spherical in shape. The beads are not amalgamated together (i.e., they are not united or combined into a unified or integrated whole, as they might be in a block of Styrofoam). Instead, the individual beads are preferably free to move about with respect to one another, within the confines of the bag 40. In one preferred embodiment, the mean diameter of the ETBs is on the order of 0.8 mm. The size distribution of the beads may be tightly centered about the mean diameter, so that most of the beads would measure between about 0.7 and 0.9 mm. Alternatively, the size distribution may vary more widely (e.g., with the size of the beads ranging from 0.6-1.2 mm). In other embodiments, the average size of the beads is between about ⅔ mm and 1 mm, or even between about a ½ and 1.5 mm. The shape of the beads may also be varied by, for example, using beads that are roughly oblate instead of spherical.
Preferably, a sufficient quantity of beads is included to form a bed that is, on average, at least about one quarter inch thick. In some embodiments, for example, the filling will have a volume of between about 2-5 cubic inches for adult size sandals, and will contain more than 10,000 beads. The preferred packing density for the beads within the bag 40 is preferably low enough so that when a user walks on the sandal, the beads can shift around to some extent (due to the pressure from the user's foot that is transmitted through the flexible walls 42 of the bag 40), but high enough so that the user's foot is supported by a layer of beads that is at least a few beads thick.
While the most preferred material for the filling 10 is expanded polystyrene beads, other types of expanded thermoplastic beads (e.g., expanded polypropylene beads) may also be used. In less preferred embodiments, other materials that share at least some characteristics (e.g., size, shape, and resiliency) with the preferred beads may be used instead of ETBs.
In the
The upper sole 62 is disposed on top of the bag 40 and secured to the lower sole assembly. The upper sole 62 is preferably a thin, flexible material (e.g., stretch cotton jersey fabric with a weight on the order of about 3.5 to 7 ounces per square yard). Other fabrics or materials may be substituted therefore, including but not limited to knit fabrics, woven fabrics, and flexible leather. Such materials are preferably selected so that the upper sole can transmit force from the user's foot to the ETBs in the bag 40, such that the ETBs can shift around to some extent in response to the changes in pressure that occur during ordinary walking. The upper sole 62 is preferably secured to either the lower sole 36 or the outsole 14 (using, for example, adhesives, stitching, or any other approach that provides a relatively strong and permanent connection). Suitable attachment surfaces include the outer surface of the sidewall 32 and/or the lower surface of the lower sole 36 and/or the upper surface of the outsole 14.
The upper sole 62 is disposed above the bag 40 so as to keep the bag confined in the footbed between the upper sole 62 and the lower sole 36. Note that although
Returning now to
In an alternative embodiment neither the bag 40 nor the upper sole 62 has button holes, and the straps 16, 18 are attached directly to the upper sole 62 (e.g., by sewing the straps 16, 18 directly to the upper sole 62).
Optionally, the straps may be stuffed with the same material that is used to fill the footbed (see reference numeral 10 in
Similar materials to those described above in connection with the upper sole 62 may be used for the walls 72, 74. The inner wall 72 is hose-shaped, with the ends of the hose closed off to keep the filling 70 contained. Because a double-walled construction is used, the inner hose 72 need not be affixed directly to the sole. Instead the inner hose is contained within an outer hose 74, and the outer hose is affixed (e.g., sewn, glued, etc.) to the sole 12. Optionally, intermediate members may be used to connect the outer hose to the sole (e.g., a member with a plug at one end for connecting to the sole and an eyelet at the other end to accept the end of the outer hose). In alternative embodiments, a single-walled construction is used, in which case the single wall must be connected to the sole (either directly or through an intermediate member).
Prototypes of the sandals described above have proven to be extremely comfortable.
While the present invention has been explained in the context of the preferred embodiments described above, various changes may be made to those embodiments and various equivalents may be substituted without departing from the scope of the invention, as will be apparent to persons skilled in the relevant art. Examples of such changes include, but are not limited to, using the ETB filling (or substitutes therefor) in other styles of sandals (e.g., T-strap sandals, athletic sandals, etc.) or in other types of footwear (e.g., insoles and footwear with uppers such as shoes, sneakers, boots, etc.).
Claims
1. A sandal comprising:
- a sole comprising (a) a lower sole, (b) a flexible upper sole, and (c) a plurality of unamalgamated beads disposed between the upper sole and the lower sole; and
- at least one strap connected to the sole and configured to secure the sole to the bottom of a user's foot.
2. The sandal of claim 1, wherein the beads that are disposed between the upper sole and the lower sole are enclosed in a thin and flexible inner bag, the bag being disposed between the upper sole and the lower sole.
3. The sandal of claim 1, wherein the upper sole is made of fabric.
4. The sandal of claim 1, wherein the upper sole is made of stretch jersey fabric.
5. The sandal of claim 1, wherein the beads are roughly spherical expanded thermoplastic beads.
6. The sandal of claim 1, wherein the beads are roughly spherical expanded polystyrene beads having an average diameter between about two thirds and about one mm, and wherein the plurality of beads comprises at least ten thousand beads.
7. The sandal of claim 6, wherein the upper sole is made of a lightweight fabric.
8. The sandal of claim 7, wherein the beads that are disposed between the upper sole and the lower sole are enclosed in an inner bag made of a lightweight fabric, the bag being disposed between the upper sole and the lower sole.
9. The sandal of claim 1, wherein the at least one strap is stuffed with unamalgamated, roughly spherical, expanded thermoplastic beads.
10. The sandal of claim 1, wherein the at least one strap is stuffed with unamalgamated, roughly spherical, expanded polystyrene beads having an average diameter between about two thirds and about one mm.
11. A shoe comprising:
- a sole comprising (a) a lower sole, (b) a flexible upper sole, and (c) a plurality of unamalgamated small beads disposed between the upper sole and the lower sole; and
- an upper connected to the sole and configured to secure the sole to the bottom of a user's foot.
12. The shoe of claim 11, wherein the beads that are disposed between the upper sole and the lower sole are enclosed in a thin and flexible inner bag, the bag being disposed between the upper sole and the lower sole.
13. The shoe of claim 11, wherein the upper sole is made of fabric.
14. The shoe of claim 11, wherein the upper sole is made of cotton jersey stretch knit fabric.
15. The shoe of claim 11, wherein the beads are roughly spherical expanded thermoplastic beads.
16. The shoe of claim 11, wherein the beads are roughly spherical expanded polystyrene beads having an average diameter between about two thirds and about one mm, and wherein the plurality of beads comprises at least ten thousand beads.
17. The shoe of claim 16, wherein the upper sole is made of a lightweight fabric.
18. The shoe of claim 17, wherein the beads that are disposed between the upper sole and the lower sole are enclosed in an inner bag made of a lightweight fabric, the bag being disposed between the upper sole and the lower sole.
19. An article of footwear comprising:
- a lower sole having an upper surface;
- sidewalls having an inner surface, wherein the sidewalls are connected to the lower sole so as to form a recess that is bounded by the inner surface of the sidewalls and the upper surface of the lower sole;
- a plurality of unamalgamated small beads disposed in the recess;
- a thin and flexible upper sole disposed on top of the beads and arranged to retain the beads within the recess; and
- wherein the beads are free to shift around within the recess when pressure is applied to the beads through the upper sole.
20. The article of footwear of claim 19, wherein:
- (a) the recess occupies an area that is at least half as large as the area of the upper sole,
- (b) at least one part of the recess is at least one about one quarter inch deep, and
- (c) the plurality of beads comprises at least ten thousand beads.
21. The article of footwear of claim 20, wherein the beads are roughly spherical expanded polystyrene beads having an average diameter between about two thirds and about one mm.
22. The article of footwear of claim 21, wherein the beads are enclosed in a bag made of a lightweight fabric, and the flexible upper sole retains the beads within the recess by retaining the bag within the recess.
23. The article of footwear of claim 21, further comprising at least one strap connected to at least one of the lower sole, the sidewalls, and the upper sole, wherein the at least one strap is adapted to hold the upper sole against the bottom of a user's foot.
24. The article of footwear of claim 21, further comprising an upper connected to at least one of the lower sole, the sidewalls, and the upper sole, wherein the upper is adapted to hold the upper sole against the bottom of a user's foot.
25. The article of footwear of claim 19, wherein the beads are roughly spherical expanded thermoplastic beads.
26. The article of footwear of claim 19, wherein the beads are roughly spherical expanded polystyrene beads having an average diameter between about two thirds and about one mm, and wherein the volume of beads includes at least ten thousand beads.
27. An article of footwear comprising:
- a volume of unamalgamated small beads;
- a lower sole disposed beneath the volume of beads; and
- a flexible covering disposed above the volume of beads,
- wherein the beads are retained between the lower sole and the flexible covering, and wherein, when the article of footwear is worn by a person that is standing or walking, the volume of beads bears at least some of the weight of the person.
28. The article of footwear of claim 27, wherein the beads are enclosed in a thin and flexible inner bag, the bag being disposed between the lower sole and the flexible covering.
29. The article of footwear of claim 27, wherein the beads are roughly spherical expanded thermoplastic beads.
30. The article of footwear of claim 27, wherein the beads are roughly spherical expanded polystyrene beads having an average diameter between about two thirds and about one mm, and wherein the volume of beads includes at least ten thousand beads.
Type: Application
Filed: Jan 14, 2004
Publication Date: Jul 14, 2005
Inventor: Gail Iannacone (New York, NY)
Application Number: 10/757,874