Patent Application
20080083138
1. Field of the Invention
The present invention relates to athletic footwear, and more specifically to an improved upper for an athletic shoe.
2. Background Art
Athletic footwear must provide stable and comfortable support for the foot. Specifically, it is important that the footwear be comfortable while providing adequate support during various foot movements associated with athletic activity. Athletic footwear typically includes an upper and a sole, and is sold in a variety of sizes according to the length and width of the foot. The standard upper, however, is typically constructed of one mesh material, with minimal stretch.
While the three main divisions of the foot are linked to each other, it is not uncommon for the three main divisions to move relative to each other during athletic activity. Although many products are designed to accommodate the shape of a foot when the foot is static, the problems associated with the fit of an upper during dynamic movement of the foot have not been adequately addressed. Specifically, the standard design of an athletic shoe, which includes only a continuous upper structure, does not provide adequate mobility between the three main divisions of the foot, i.e., rearfoot 102, midfoot 104, and forefoot 106.
This brief summary is intended to summarize the claims filed in the present patent application. This summary is not intended to be limiting. Therefore, the filed claims, and any future iterations of the claims, should not be limited by this summary.
Presented herein is a shoe having an improved upper. The upper is generally comprised of a plurality of non-stretch panels interlinked with at least one stretchable expansion joint. The stretchable expansion joint provides relative movement between the plurality of non-stretch panels such that the upper mimics the relative movement between the bone structures of a wearer's foot.
In one embodiment presented herein, there is provided an article of footwear having a sole and an upper attached to the sole, wherein the upper is comprised of at least four non-stretch panels and at least one expansion joint formed of a stretch material. The expansion joint has an approximate X-shape configuration. The X-shape configuration forms four quadrants about a center point. Each of the four non-stretch panels is disposed in one of the four quadrants formed by the X-shape configuration. In one embodiment, the X-shape configuration is formed by four extensions departing from the center point, two of the extensions extending from the center point to a front portion of the sole, one extension extending from the center point to a medial side of the sole, and one extension extending from the center point to a lateral side of the sole. In one embodiment, the center point is located in an area corresponding to a forefoot portion of the sole. The expansion joint may be formed of a two-way expandable material or a four-way expandable material. The expansion joint may be formed of a spandex material or a spandex material having a polyurethane coating. In one embodiment, a portion of the expansion joint is about three millimeter to about four millimeters wide. In one embodiment, the expansion joint is comprised of a material having a stretch retention of less than about 15%, and preferably less than about 5%.
In accordance with another embodiment presented herein, there is provided an article of footwear having a sole and an upper attached to the sole, wherein the upper is comprised of a forefoot portion, an expansion joint coupled to the forefoot portion, and a rearfoot portion coupled to the rearfoot portion. The forefoot portion and the rearfoot portion are formed of non-stretch materials. The expansion joint is formed of a stretch material having a stretch retention of less than about 15%, and preferably less than about 5%. The expansion joint extends from a medial side of the sole to a lateral side of the sole.
The accompanying figures, which are incorporated herein and form part of the specification, illustrate an athletic shoe. Together with the description, the figures further serve to explain the principles of the athletic shoe described herein and thereby enable a person skilled in the pertinent art to make and use the athletic shoe.
Preferred embodiments of an athletic shoe are described below with reference to the figures where like reference numbers indicate identical or functionally similar elements. Also in the figures, the left most digit of each reference number corresponds to the figure in which the reference number is used. While specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the relevant art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the appended claims.
Upper 206, as shown in
The number of panels that comprise upper 206 is not restricted to just three panels. Any number of panels between two and about seven may be used. The objective of the panels is to mimic the relative movement of the different areas of the foot. For that reason, three panels are preferred because the foot is generally divided into three main divisions; specifically the forefoot, midfoot, and rearfoot. In this manner, upper 206 can move with the foot. In a typical shoe, the lack of stretch and mobility in the upper creates relative movement between the foot and the upper, which in turn creates blisters and sore spots. In contrast to a typical shoe, the mobility between panels 212, 214, and 216 in upper 206 works to prevent blisters and sore spots.
The expansion joints are preferably formed of a synthetic material. For example, the expansion joints may be formed of a midbacker coated with polyurethane. The midbacker can be a material such as spandex. Alternatively, the expansion joints may be straight textile spandex. Preferably, the expansion joints are formed of a four-way stretch material. In alternative embodiments the expansion joints may be formed of a two-way stretch material. Further, the expansion joints are preferably formed of a material having a greater stretch characteristic than that of the panels. For example, under an Elastic Gore Retention test, a preferred material for the expansion joints would have a maximum stretch retention of less than 15%, and more preferably a maximum stretch retention of less than 5%.
The expansion joints are typically attached to the panels through a zig-zag stitch between the panels. After stitching, the panels may be overlaid with a synthetic material. In a preferred embodiment, the panels are separated from each other by a gap of about three to four millimeters. In alternative embodiments, the expansion joints may be sewn on, RF welded, or attached to the panels by any other attachment operation known to the art.
In one embodiment, non-stretch portion 740 is laid over stretch mesh portion 730 and attached to stretch mesh portion 730 by conventional means. In one embodiment, non-stretch portion 740 has a plurality of “fingers” 742 that extend upward from the bottom of upper 706. In between fingers 742 is stretch mesh portion 730. In one embodiment, shoe 700 includes five stretch mesh portions 730 on each side of shoe 700. Each of the five stretch mesh portions 730 on each side of shoe 700 may be sewn between the fingers 742. In alternative embodiments, any number of stretch mesh portions 730 may be employed. For example, in one embodiment, only one stretch mesh portion 730 is disposed on each side of shoe 700. Such embodiment may have the stretch mesh portion 730 disposed over a portion of the shoe that approximately corresponds with the arch of a wear's foot.
As such, stretch mesh portion 730 serves as expansion joints between fingers 742. Shoe 700 may include shoelaces 710, tongue portion 708, comfort padding 722, and outsole 702, as described in the previous embodiments above. In one embodiment, upper 706 includes up to about fifteen millimeters, and preferably between about ten and about fifteen millimeters, of non-stretch material 740 running along the base of upper 706—where upper 706 attaches to midsole 704.
The shoes described above may be manufactured by a method comprising: a) securing a portion of a first expansion joint to a portion of a forefoot panel; b) securing a mid-section panel to a portion of the first expansion joint; c) securing a second expansion joint to a portion of the mid-section panel; and d) securing a rearfoot panel to a second portion of the second expansion. The panels may be secured to one another by being sewn together, by an RF welding technique, or using a zig-zag stitch technique. The upper is then preferably attached to a sole of a shoe. In an alternative method presented herein, a portion of an end of the forefoot panel is spaced about three to four millimeters from a portion of a first end of the mid-section panel, and a portion of a second end of the mid-section panel is spaced about three to four millimeters from a portion of an end of the rearfoot panel.
The shoes described above may also be manufactured by the alternative method of: a) providing one unitary upper formed of a stretch material; and b) securing onto the stretch material a second material, which is less stretchable than said stretch material.
Although it is acknowledged that most materials are stretchable to a certain extent, as used herein the terms “stretch material,” “stretchable material,” “non-stretch material,” and “non-stretchable material” are terms of art. More specifically, the term “stretch” or “stretchable” is intended to refer to materials which have a maximum stretch retention of less than 15%, and more preferably a maximum stretch retention of less than 5%, under an Elastic Gore Retention test. In such a test, a swatch of material is first measured in an unloaded and neutral state. The material is then stretched or extended to, for example, one and a half times its original length and/or width. The material is then measured again in an unloaded and neutral state. The second measurement is intended to determine the material's ability to return to its original size. A material that returns to within 15% of its original size, may be considered a “stretch” or “stretchable” material. However, materials that either fail during extension, or do not return to within 15% of its original size, may be considered a “non-stretch” or “non-stretchable” material.
While various embodiments of an athletic shoe have been described, it should be understood that they have been presented by way of example, and not limitation. For example, the illustrated design and direction of the expansion joints were not intended to be limiting. Further, the forefoot, mid-section, and rearfoot panels may take on any form or configuration desirable to a designer. Further, the terms “forefoot,” “mid-section,” “midfoot,” and “rearfoot” are not intended to be limited to the exact bone structure of a wearer's foot, or the bone structure shown in
It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the appended claims. For example, the upper could be made to conform to the movement of the foot by using numerous expansion joints, at various locations, to allow the upper to move with the movement of the foot while retaining sufficient support. The expansion joints need not be formed of the same material. Portions of the foot which require more expansion may use a material having a different stretch property than the material used in portions of the foot having less movement. Thus, a shoe can be tailored to accommodate the specific movements of the foot. Thus the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.
This application is a Continuation-in-Part of U.S. patent application Ser. No. 11/496,714, filed Aug. 1, 2006, the entire disclosure of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11496714 | Aug 2006 | US |
| Child | 11733626 | Apr 2007 | US |
