FOOTWEAR MIDSOLE COMPRISING AN INTERNAL BLADDER

Abstract

The presently disclosed subject matter is directed to a footwear midsole configured as an air-filled bladder formed from one or more exterior walls. The interior of the midsole comprises one or more fluids (e.g., gases or liquids). The midsole further includes a covering that partially or fully covers the interior compartment. The covering is formed form an elastomeric material that allows exclusive top-down compression of the midsole. Accordingly, the midsole provides a reactive opposed rebound force supplied by the elastomeric covering in response to compression.

Claims

1. A footwear midsole comprising: an interior compartment comprising a fluid; and an elastomeric covering spanning at least a portion of an exterior surface of the interior; wherein the midsole enables top-down compression when a force is exerted upon the midsole.

2. The midsole of claim 1, further comprising an inflation housing that allows fluid to be added or removed from the interior compartment.

3. The midsole of claim 1, wherein the fluid comprises a gas, a liquid, or combinations thereof.

4. The midsole of claim 1, wherein the fluid is selected from ambient air, nitrogen, carbon dioxide, helium, or combinations thereof.

5. The midsole of claim 1, wherein the fluid is selected from water, saline, or combinations thereof.

6. The midsole of claim 1, wherein the elastomeric material is selected from natural or synthetic rubber, natural or synthetic rubber blends, polyisoprene, polybutadiene, chloroprene rubber, butyl rubber, styrene-butadiene rubber, nitrile rubber, silicone, polyether block amides, ethylene-vinyl acetate, thermoplastic elastomers, polyurethane, polyester, polyester polyurethane, polyether polyurethane, or combinations thereof.

7. The midsole of claim 1, wherein the interior compartment has a volume of about 40-200 cubic centimeters.

8. The midsole of claim 1, wherein the covering is releasably attached to the midsole.

9. The midsole of claim 1, wherein the covering is attached to a top surface of the midsole.

10. The midsole of claim 1, wherein the covering creates an air-tight seal around the midsole interior compartment.

11. The midsole of claim 1, wherein the interior compartment includes two or more sub-compartments.

12. The midsole of claim 11, wherein at least one sub-compartment is in fluid communication with at least one other sub-compartment.

13. The midsole of claim 1, wherein the interior compartment is filled to about 40-100 percent capacity.

14. The midsole of claim 1, wherein the fluid within the midsole interior has a pressure of about 0-350 kPa.

15. An article of footwear comprising: a sole; and an upper; wherein the sole comprises a midsole defined by: an interior compartment comprising a fluid; and an elastomeric covering spanning at least a portion of an exterior surface of the interior; wherein the midsole enables top-down compression when a force is exerted upon the midsole.

16. The article of claim 15, wherein the sole further comprises an insole and an outsole.

17. The article of claim 15, wherein the elastomeric material is selected from natural or synthetic rubber, natural or synthetic rubber blends, polyisoprene, polybutadiene, chloroprene rubber, butyl rubber, styrene-butadiene rubber, nitrile rubber, silicone, polyether block amides, ethylene-vinyl acetate, thermoplastic elastomers, polyurethane, polyester, polyester polyurethane, polyether polyurethane, or combinations thereof.

18. The article of claim 15, wherein the fluid comprises a gas, a liquid, or combinations thereof.

19. The article of claim 15, wherein the interior compartment includes two or more sub-compartments.

20. The article of claim 15, wherein the fluid within the midsole interior has a pressure of about 0-350 kPa.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1a is a side plan view of footwear comprising a midsole in accordance with some embodiments of the presently disclosed subject matter.

[0020] FIG. 1b is a side plan view of a footwear sole in accordance with some embodiments of the presently disclosed subject matter.

[0021] FIG. 2a is a side plan view of a midsole in accordance with some embodiments of the presently disclosed subject matter.

[0022] FIG. 2b is a side plan view of a midsole in accordance with some embodiments of the presently disclosed subject matter.

[0023] FIG. 3 is a fragmentary view of a midsole inflation housing in accordance with some embodiments of the presently disclosed subject matter.

[0024] FIGS. 4a-4g are top plan views of midsoles comprising one or more compartments in accordance with some embodiments of the presently disclosed subject matter.

[0025] FIGS. 5a-5d are side plan views of one embodiment of using the disclosed midsole.

DETAILED DESCRIPTION

[0026] The presently disclosed subject matter is introduced with sufficient details to provide an understanding of one or more particular embodiments of broader inventive subject matters. The descriptions expound upon and exemplify features of those embodiments without limiting the inventive subject matters to the explicitly described embodiments and features. Considerations in view of these descriptions will likely give rise to additional and similar embodiments and features without departing from the scope of the presently disclosed subject matter.

[0027] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the presently disclosed subject matter pertains. Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the presently disclosed subject matter, representative methods, devices, and materials are now described.

[0028] Following long-standing patent law convention, the terms “a”, “an”, and “the” refer to “one or more” when used in the subject specification, including the claims. Thus, for example, reference to “a device” can include a plurality of such devices, and so forth.

[0029] Unless otherwise indicated, all numbers expressing quantities of components, conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the instant specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the presently disclosed subject matter.

[0030] As used herein, the term “about”, when referring to a value or to an amount of mass, weight, time, volume, concentration, and/or percentage can encompass variations of, in some embodiments +/−20%, in some embodiments +/−10%, in some embodiments +/−5%, in some embodiments +/−1%, in some embodiments +/−0.5%, and in some embodiments +/−0.1%, from the specified amount, as such variations are appropriate in the disclosed packages and methods.

[0031] FIG. 1a illustrates one embodiment of footwear 5 configured as an athletic shoe that includes a midsole structure in accordance with the presently disclosed subject matter. The midsole can be configured for use with various kinds of footwear, such as hiking boots, soccer shoes, football shoes, running shoes, cross-training shoes, rugby shoes, basketball shoes, baseball shoes, and the like. It should be appreciated that the footwear can also include non-athletic shoes, such as slippers, sandals, high heeled shoes, loafers, etc. Thus, the term “footwear” broadly refers to any foot covering, including (but not limited to) athletic shoes, boots, sandals, and the like.

[0032] For reference purposes, footwear 5 can be divided into three general regions: forefoot region 30, midfoot region 31, and heel region 32, as shown in FIG. 1a. Forefoot region 30 generally includes portions of footwear 5 corresponding with the toes and the joints connecting the metatarsals with the phalanges. Midfoot region 31 generally includes portions of the footwear corresponding with the arch area of the foot, and heel region 32 corresponds with rear portions of the foot, including the calcaneus bone. It should be appreciated that regions 30-32 are not intended to demarcate precise areas of footwear 5. Rather, the regions are intended to represent general areas of the footwear.

[0033] As shown, footwear 5 includes upper 10 designed to securely enclose at least a portion of the wearer's foot. Upper 10 can have any of a wide variety of configurations incorporating a range of conventional materials, such as (but not limited to) textiles, foam, leather, vinyl, nylon, and the like. The material elements can be selected and positioned in upper 10 to selectively impart one or more desired properties (e.g., durability, air-permeability, wear-resistance, flexibility, comfort, and the like). The materials are stitched or adhesively bonded together to form interior void 20 for securely and comfortably receiving at least a portion of the wearer's foot. In some embodiments, upper 10 can include closure 25 configured as a shoelace, zipper, snap, button, VELCRO®, etc. that is utilized to secure the wearer's foot within the interior void of the footwear. The closure also facilitates entry and removal of the foot from the footwear. In some embodiments, the closure can extend through apertures in upper 10, and a tongue portion can extend between the interior void and the closure.

[0034] It should be appreciated that upper 10 can have any design, shape, size and/or color. For example, in embodiments wherein the footwear is a basketball shoe, the upper can be configured as a high top that is shaped to provide added support on the wearer's ankle. Alternatively, when footwear 5 is a running shoe, upper 10 can be configured with a low profile.

[0035] In addition to upper 10, footwear 5 comprises sole 15 that functions to absorb the impact forces on the wearer's foot during use. In some embodiments, the sole can extend generally the entire length of the footwear from toe region 16 to the heel portion 17, as shown in FIG. 1a. The sole is secured to a lower face of upper 10 using any known method, such as (but not limited to) the use of adhesive, sewing, thermal bonding, mechanical elements, and the like. The sole is positioned between upper 10 and the ground, thereby extending between the foot and the ground. In this way, the sole can provide traction, impart stability, and limit various foot motions (such as pronation).

[0036] FIG. 1b illustrates one embodiment of sole 15. As illustrated, the primary elements of sole 15 include insole 35, midsole 40 and outsole 45. In some cases, one or more of these components can be optional. Insole 35 is positioned within the interior void in upper 20 and is located to correspond with a plantar (i.e., lower) surface of the foot, thereby enhancing the comfort of footwear 10. Midsole 40 is secured to a lower surface of the insole and attenuates ground reaction forces as sole 15 is compressed between the foot and the ground, such as during walking or running. Midsole 40 may also absorb energy when compressed. Midsole 40 includes a sealed fluid-filled chamber, which will be discussed in detail below. The outsole is the outer surface of the footwear that contacts the ground. Outsole 45 is secured to a lower surface of the midsole and is formed from a durable and abrasion-resistant material (such as rubber) that can be textured to define various protrusions for providing traction.

[0037] One embodiment of midsole 40 is depicted in FIG. 2a. As shown, the midsole can include provisions for shock absorption, cushioning, and comfort. Particularly, the midsole can be configured as an air-filled bladder formed from one or more exterior walls 50. The exterior walls can include any suitable material used to contain a fluid-filled interior. For example, suitable materials can include (but are not limited to) polymeric material, rubber, elastomeric material, and the like. Interior 51 is filled with any desirable fluid. The term “fluid” as used herein refers to any suitable liquid, gas, or combination thereof. Suitable gases can include (but are not limited to) one or more of ambient air, nitrogen, helium, carbon dioxide, etc. Suitable liquids can include (but are not limited to) water, saline, or combinations thereof. The exterior walls of the midsole are sealed to contain the fluid.

[0038] The interior of midsole 40 can house any desired volume of fluid. For example, the midsole can have an interior volume of about 40-200 cc (cubic centimeters). Thus, the internal volume of the midsole can be at least/no more than about 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200 cc. It should be appreciated that the volume of the midsole depends on the size of the midsole (e.g., the size of the user's foot). It should further be appreciated that the midsole can have a volume greater or less than the range given herein.

[0039] Midsole 40 can have a thickness 41 of about 0.1-3 inches, as shown in FIG. 2a. The term “thickness” as used herein refers to the measurement of an insole from its top surface to its opposing bottom surface. The midsole can have a thickness at rest of at least about (or no more than about) 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3 inches. “At rest” refers to the thickness without contact with the wearer's food (e.g., an uncompressed state). It should be appreciated that the midsole thickness is not limited and can be greater or less than the range given herein.

[0040] In some embodiments, the midsole is configured to be about the entire length of the footwear, as shown in FIG. 2a. Thus, the midsole can have length 42 of about 5-16 inches, depending on the size of the wearer's foot (e.g., at least/no more than about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 inches). However, the length of the midsole is not limited and can be greater or less than the range given herein.

[0041] The midsole is at least partially enclosed by covering 55 as shown in FIGS. 2a and 2b. Specifically, the covering can be positioned on the top surface or can surround all or a portion of the exterior surface of the midsole. The covering can be releasably or permanently attached to the midsole to create an air-tight seal. Covering 55 can be attached to the midsole using any known method, such as (but not limited to) adhesives, welding, heat sealing, etc.

[0042] Covering 55 can be constructed from any desired material. For example, in some embodiments, the covering can be constructed from one or more elastomeric materials. The term “elastomeric” refers to a material that can be elongated or extended by at least 5, 10, 15, 20, or 25% of its relaxed length and that will recover upon release of the applied force. Suitable elastomeric materials can include (but are not limited to) natural or synthetic rubber, natural or synthetic rubber blends, polyisoprene, polybutadiene, chloroprene rubber, butyl rubber, styrene-butadiene rubber, nitrile rubber, silicone, polyether block amides, ethylene-vinyl acetate, thermoplastic elastomers, polyurethane, polyester, polyester polyurethane, polyether polyurethane, or combinations thereof.

[0043] The covering can have a thickness of about 0.001-100 mm. Thus, the covering can have a thickness of at least about (or no more than about) 0.001, 0.005, 0.01, 0.015, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 mm. However, it should be appreciated that the thickness of the covering is not limited and can be thicker or thinner than the range given herein.

[0044] Optionally, midsole 40 can include housing 60 that facilitates the inflation of the midsole. The housing can be disposed on any surface of the midsole to allow fluid to be selectively added or removed from the midsole interior by the user, as illustrated in FIG. 3. In operation, a fluid (such as ambient air) passes through the housing into the interior of midsole 40. The housing can therefore include a port, valve, plug, aperture, or combinations thereof. In some embodiments, the housing can be a one-way or two-way valve. In some embodiments, the housing can be configured as a check valve that will open when the pressure within the midsole interior is at or greater than a predetermined level.

[0045] A variety of different inflation mechanisms can be utilized with housing 60. For example, the inflation mechanism can include a simple bulb that interacts with the housing to add or remove fluid from the midsole interior. Alternatively, a pump (e.g., a handheld pump) can be used to inflate the midsole.

[0046] In some embodiments, the interior of the midsole can be filled to about 100% with a desired fluid. In other embodiments, interior 51 is less than fully filled. For example, midsole can be filled to about 40-100% capacity. Thus, the midsole can be filled to a level of at least about (or no more than about) 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or 100 percent. In some embodiments, the fluid within the midsole interior can be pressurized between 0-350 kPa (e.g., at least/no more than about 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, 250, 255, 260, 265, 270, 275, 280, 285, 290, 295, 300, 305, 310, 315, 320, 325, 330, 335, 340, 345, or 350 kPa).

[0047] In some embodiments, the midsole can be divided into one or more compartments 65. For example, as shown in FIGS. 4a-4c, the compartments can be configured in a longitudinal direction, crosswise direction, or combinations thereof.

[0048] In some embodiments, the compartments span the full midsole, as shown in FIGS. 4a-4c. However, the presently disclosed subject matter also includes embodiments wherein the compartments are limited to one or more sections of the insole (e.g., the forefoot region, midfoot region, and/or heel region), as illustrated in the embodiments of FIGS. 4d and 4e.

[0049] It should further be appreciated that the midsole can include a single compartment, as illustrated in FIG. 4f. As shown, compartment 65 can extend under substantially all of the wearer's foot.

[0050] In some embodiments, the compartments are separated from adjacent compartments as shown in FIG. 4a. Alternatively, one or more compartments may be in fluid communication with at least one other compartment, as shown in FIG. 4g. In this way, the movement of air between compartments is permitted and can be controlled by the size of opening 66.

[0051] The compartments can be inflated to the same or different pressures depending on the type and amount of cushioning needed.

[0052] The shape of compartments 65 is not limited and can be configured in any desired shape and size, such as (but not limited to), square, rectangular, rounded, serpentine, abstract, and the like. The shape and/or size of each compartment can be about the same or can differ relative to at least one other compartment.

[0053] It should be appreciated that midsole 40 can include any number of compartments 65, such as about 1-10. However, the presently disclosed subject matter is not limited and the midsole can have more than 10 compartments (e.g., 10-100 compartments).

[0054] The midsole can be manufactured using any known method. For example, two separate layers of material (e.g., elastomeric film) are formed to have the overall shape of the midsole. The layers are then bonded together along their respective peripheries to form an upper surface, a lower surface, and sidewalls of the chamber. The layers can optionally be bonded together at predetermined interior locations to produce one or more compartments 65. The midsole (or compartment(s) can optionally be pressurized by inserting a nozzle or needle, which is connected to a fluid pressure source, into a fill inlet formed in the midsole. After the midsole is pressurized, the nozzle is removed, and the fill inlet is sealed. Covering 55 can be permanently or removably attached to at last one portion of the exterior surface of the midsole using known methods (e.g., adhesives, thermal sealing, etc.). However, the presently disclosed subject matter is not limited and the midsole can be formed using any known method.

[0055] Advantageously, midsole 40 provides improved shock absorption and running/leaping efficiency compared to prior art midsoles. As described above, a fluid (which can be air at atmospheric pressure) is trapped within the midsole interior. In some embodiments, the fluid can be contained in one or more compartments 65. In use, when a user is standing in the footwear, the fluid in the midsole provides a cushioning effect, as shown in FIG. 5a. However, when the wearer runs or steps, the midsole is compressed exclusively from the top-down. Particularly, the heel portion of the outsole first comes into contact with the ground. As a result, the heel of the wearer's foot exerts a downward pressure on midsole 40. The fluid within the midsole in the area of the heel pressure will then be compressed as shown by the arrow in FIG. 5b. In some embodiments, the compressed fluid will travel through compartments 65.

[0056] In response to the compression, the fluid positioned within the interior of the midsole provides a reactive force upon release to give a lifting effect, as the wearer's weight shifts to the front part of the foot. The reactive force is performed by covering 55 due to the elastomeric nature of the material used, as shown by the arrows in FIGS. 5c and 5d. The reactive force can be exerted on the user's foot (heel, middle, or ball positions) in the form of a rebound force. Thus, in walking and running (and other movements), the fluid is compressed and then the covering provides the rebound force to give an alternating lifting effect and provide thrust that facilitates walking and running. As a result, the midsole provides improved shock absorption and allows the wearer greater mobility when running, leaping, etc.

[0057] Although midsole 40 may be especially advantageous when used with athletic shoes, the presently disclosed subject matter is not limited and the midsole can be used with any type of footwear.

[0058] The disclosed midsole therefore provides for a unique top-bottom compression, enabled by elastomeric covering. As a result, the reactive force that occurs after compression provides a benefit to the wearer in the form of a burst of compression release.

[0059] The disclosed midsole is simple to manufacture and can be easily used with existing footwear.

[0060] The presently disclosed subject matter is disclosed above and in the accompanying drawings with reference to a variety of embodiments. The purpose served by the disclosure, however, is to provide an example of the various features and concepts related to the invention, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications can be made to the embodiments described above without departing from the scope of the present invention, as defined by the appended claims.