ADJUSTABLE FOOTWEAR SOLE WITH BLADDER

Abstract

An article of footwear includes an upper and a sole secured thereto. The sole includes a midsole with a receptacle, within which a flexible fluid-filled bladder may be fitted. The bladder is adjustable with respect to the midsole between at least first and second orientations. The bladder provides the sole with a first characteristic when in the first orientation and a second characteristic, different from the first characteristic, when in the second orientation. Accordingly, the sole is readily adjustable between the first characteristic and the second characteristic by movement of the bladder with respect to the midsole.

Description

BACKGROUND OF THE INVENTION

The present invention relates to footwear and more particularly to footwear having a fluid-filled bladder in the sole.

The design and manufacture of footwear is complicated by the fact that different people have different footwear needs. For example, some individuals prefer a firmer, more unyielding sole, while others prefer a softer, more cushioning sole. With some people this is simply an aesthetic desire, but for others it can result from physical factors, such as those associated with foot shape, skeletal alignment and other anatomical issues. Anatomical issues cause some individuals to suffer from a tendency to pronate (roll their feet inward when striding) and others to have the opposite tendency to supinate (roll their feet outward when striding). One method for addressing these issues is to stiffen the sole in select regions to provide increased resistance against the undesired motion. For example, pronation can be addressed by providing a dual-density midsole with a higher density region along the medial side of the sole. Similarly, supination can be addressed by providing a dual-density midsole with a higher density region along the lateral side of the sole.

Additionally, some footwear products include cushioning inserts which may be in the form of resilient pads or fluid filled bladders. Many of the conventional fluid filled bladders have been filled with a gas, such as air, while others have been filled with liquids or viscous gel. These fluid filled bladders may be manufactured in several ways, including welding two layers of elastomeric film together. The bladder is then pressurized by inserting a nozzle or needle, which is connected to a fluid pressure source, into a fill inlet formed in the bladder. After the bladder is pressurized, the nozzle is removed and the fill inlet is sealed, for example by welding.

SUMMARY OF THE INVENTION

The present invention provides an article of footwear having an upper and a sole secured to the upper. The sole includes a midsole with a receptacle, within which a flexible fluid-filled bladder may be fitted. The bladder is adjustable with respect to the midsole between at least first and second orientations. The bladder provides the sole with first characteristics when in the first orientation and second characteristics, different from the first characteristics, when in the second orientation. Accordingly, the sole is readily adjustable between the first characteristics and the second characteristics by movement of the bladder with respect to the midsole.

In one embodiment, a sole for an article of footwear includes a midsole with at least one receptacle and an adjustable, fluid-filled bladder fitted within the receptacle. The bladder is adapted to fit into the receptacle in a plurality of orientations so as to provide the sole with different characteristics. Further, adjustment of the characteristics of the sole may be achieved by selectively fitting the bladder into the receptacle in a desired one of the plurality of orientations.

In yet another embodiment, an article of footwear includes an upper and a sole secured to the upper. The sole includes a midsole and a flexible fluid-filled bladder fitted within the midsole. The bladder has a substantially vertical axis and is adjustable with respect to the midsole between at least first and second orientations. The bladder provides the sole with first characteristics when in the first orientation and second characteristics, different from the first characteristics, when in the second orientation. Further, the midsole includes a receptacle for engagement with the bladder, the receptacle having an interface surface with a plurality of projections. The bladder also includes an interface surface with a plurality of projections matingly engaged with the plurality of projections on the receptacle interface surface. The bladder defines at least two discrete fluid chambers, and the bladder is movable with respect to the receptacle between at least a supination orientation to address problems associated with supination, a pronation orientation to address problems associated with pronation, a regular orientation, and a firm orientation.

These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the current embodiment and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a mid-line cross sectional view of an article of footwear according to one embodiment of the present invention;

FIG. 2 is mid-line cross sectional view of a midsole and bladder of the article of footwear shown in FIG. 1;

FIG. 3 is a top plan view of the midsole;

FIG. 4 is a top plan view of the midsole and installed bladder;

FIG. 5 is a detailed, top isometric view of a receptacle of the midsole;

FIG. 6 is a side elevational view of a portion of the midsole and installed bladder;

FIG. 7 is a top isometric view of the bladder;

FIG. 8 is a bottom isometric view of the bladder;

FIG. 9 is a cross-sectional view of the bladder, taken along line IX-IX of FIG. 8;

FIG. 10 is a cross-sectional view of the bladder, taken along line X-X of FIG. 8;

FIG. 11 is a schematic view of the bladder;

FIG. 12 is a schematic view of the bladder, illustrating the flow of fluid within chambers of the bladder during a heel strike;

FIG. 13 is a cross-sectional view of the midsole and bladder, taken along line XIII-XIII of FIG. 4;

FIG. 14 is a cross-sectional view of the midsole and bladder, taken along line XIII-XIII of FIG. 4, illustrating the flow of fluid within the chambers of the bladder during a heel strike;

FIG. 15 is a mid-line cross sectional view of an article of footwear according to another embodiment of the present invention; and

FIG. 16 is mid-line cross sectional view of a midsole and bladder of the article of footwear shown in FIG. 15.

DESCRIPTION OF THE CURRENT EMBODIMENT

An article of footwear in accordance with an embodiment of the present invention is shown in FIGS. 1-16 and generally designated 9. The illustrated embodiment of the article of footwear 9 generally includes a footwear sole 10, an upper 11 to which the sole 10 is secured, and an outsole 16 which may also include a heel wedge (not shown). The sole 10 includes a midsole 12 and a flexible fluid-filled bladder 14. The midsole 12 includes a receptacle 18 adapted to receive the bladder 14.

The sole 10 may be seated within essentially any article of footwear. For purposes of disclosure, the present invention is described in connection with a midsole construction. The present invention may, however, be integrated into other midsoles, such as an outsole, an insole or a heel wedge. In a midsole construction, the sole is typically disposed above or seated within a void in the outsole. Further, the present invention is described in connection with a bladder positioned in the heel region. A bladder may alternatively or additionally be positioned in other regions of the sole, such as under the forefoot or other locations where the type of adjustability provided by this construction may be desirable.

The present invention is primarily described in connection with a sole 10 configured to be incorporated into a left shoe 9. The sole for the right shoe may be a mirror image of the described left sole 10. Accordingly, the right bladder may be a mirror image of the left bladder 14.

Referring to FIGS. 1-6, the midsole 12 provides the main cushioning body of the sole 10. The midsole 12 of this embodiment is a full-length midsole that follows the general shape of an article of footwear and is configured to be fitted into the upper 11 above the outsole 16 or other underlying sole component. The midsole 12 of this embodiment is a single unitary construction that is essentially coextensive with the outsole 16, however, the midsole may be a collection of separate components or may be a partial midsole configured to extend through only one or more select portions of the sole. Referring again to the illustrated embodiment, the midsole 12 includes a forefoot region 30, an arch region 32, and a heel region 34. The forefoot region 30 is configured to support the wearer's forefoot. The arch region 32 may be shaped to provide an arch support. The heel region 34 includes the receptacle 18, which is configured to receive the bladder 14. Although this embodiment shows a single receptacle 18 in the heel region 34, the receptacle 18 may be located in other positions, such as in the forefoot region 30, and the midsole 12 may define a plurality of receptacles 18 configured to receive a plurality of bladders 14. For example, separate bladders 14 may be located in the heel region 34 and in the forefoot region 30 to provide adjustability in both areas of the sole 10. In the illustrated embodiment, the receptacle 18 is a generally disc-shaped void into which the bladder 14 may simply be inserted.

The receptacle 18 has a top surface 20, also referred to as an interface surface, which may include a plurality of projections or lobes 26. The lobes 26 may be positioned on the top surface 20 in a pattern of regular waves coinciding with angular sections of the receptacle 18. In the illustrated embodiment, the receptacle 18 includes eight lobes 26 arranged in a regular repeating pattern about the center of the top surface 20; however, more or fewer lobes 26 are also contemplated. Although the lobes 26 of the illustrated embodiment are formed by smooth and continuous curved contours, the term “lobes” is used broadly to refer to essentially any contours, whether or not such contours are curved, smooth or run continuously together. The top surface 20 of the receptacle 18 may also include a support layer (not shown), such as a thin layer of TPU or a harder EVA. The size, shape and configuration of the optional support layer may be varied from application to application to provide the desired level of cushion/support while maintaining structural integrity. Additionally, the article of footwear 9 may also include an optional sock liner 44 (FIG. 1). The design and configuration of the sock liner 44 may vary from application to application.

The midsole 12 may be manufactured from essentially any suitable material or combination of materials capable of providing the desired cushioning/support characteristics. The hardness of the midsole 12 may vary from application to application as desired. The midsole 12 may be manufactured using essentially conventional molding techniques and apparatus. The midsole 12 may be injection molded as a single integral unit in which the receptacle 18 is formed during the molding process. The midsole 12 may alternatively be pre-manufactured (e.g. pre-molded) and then die cut or otherwise processed to form the receptacle 18. The midsole 12 may alternatively be manufactured from a plurality of multiple components, for example, with separate heel and forefoot portions. The separate components may be combined during manufacture, such as by compression molding or through the use of adhesives.

Referring now to FIGS. 7-10, the bladder 14 is a generally disc-shaped member that has a substantially vertical axis 58 and that defines at least two discrete fluid chambers. In the illustrated embodiment, the bladder 14 includes a first chamber 50 and a second chamber 52. The bladder 14 may also include a center chamber 54. In the illustrated embodiment, the center chamber 54 is circular and is located at the center of the circular bladder 14. The first and second chambers 50, 52 are substantially semi-circular and encircle the center chamber 54. The first and second chambers 50, 52 are shown being substantially equivalent in size and proportion; however, it is contemplated that the split between the first and second chambers 50, 52 may be unequal; a 60/40 split, for example. Other geometries for the chambers 50-54 are also feasible; for example, a square center chamber 54 surrounded by mirror image first and second chambers 50, 52.

According to an embodiment, the pressure of the fluid within the discrete chambers 50, 52 may be different relative to one another, thereby providing differing pressure distributions to the wearer's heel depending on the orientation of the bladder 14. For example, the fluid pressure within the first chamber 50 may be provided at a predetermined first pressure P1, and the fluid pressure within the second chamber 52 may be provided at a predetermined second pressure P2 that is higher than the first pressure P1. The different pressures P1, P2 within the chambers 50, 52 provide different support and cushioning characteristics to the sole 10. Additionally, the center chamber 54 may be fluidly communicable with one of the first and second chambers 50, 52. In the illustrated embodiment, the center chamber 54 is fluidly communicable with the second chamber 52, and the pressure in the center chamber 54 is therefore equal to the second pressure P2 of the second chamber 52. Schematics of the bladder 14, depicting the chambers 50-54, are shown in FIGS. 11 and 12. Although not shown, alternately, the center chamber 54 may be fluidly communicable with the first chamber 50 and have a pressure equal to the first pressure P1 of the first chamber 50. Further, the chambers 50-54 may be filled with air, Nitrogen gas, water, or any other suitable liquid, gas, or viscous gel. Exemplary values for the pressures P1 and P2 are 9 psi and 12 psi; these values are for exemplary purposes only, and are not to be considered so limiting.

Referring to FIG. 6, the fluid-filled bladder 14 is configured to be removably seated within the receptacle 18. The bladder 14 has a bottom surface 22, also referred to as an interface surface, which includes the plurality of projections or lobes 24 configured to be interfitted with and to matingly engage the lobes 26 of the receptacle 18. One or more of the lobes 24, 26 may vary in size, shape, resiliency, rigidity or other characteristic from the remainder of the lobes 24, 26. For example, the lobes 24, 26 may vary in height. Other alternative geometries, configurations and characteristics are disclosed in co-owned U.S. Pat. No. 7,950,168, entitled “Adjustable Footwear Sole Construction,” U.S. Pat. No. 7,950,167, entitled “Adjustable Footwear Sole Construction,” and U.S. patent application Ser. No. 12/496,177, entitled “Sole Construction and Related Method of Manufacture,” the disclosures of which are hereby incorporated by reference in their entirety. Additionally, the lobes 24, 26 may be formed of any suitable undulations, ridges, and lobes.

The bladder 14 is adapted to removably fit into the receptacle 18 in a plurality of orientations to provide the sole 10 with different characteristics. The orientation of the bladder 14 is adjustable with respect to the midsole 12 (and receptacle 18) by rotation about the axis 58. Rotating the bladder 14 causes repositioning of both the lobes 24 and the first and second chambers 50, 52, which results in variation of the support/cushioning characteristics of the sole 10. For example, the bladder 14 is selectively adjustable with respect to the midsole 12 between first and second orientations. The bladder 14 provides the sole 10 with first characteristics when in a first orientation A, and provides the sole 10 with second characteristics, different from the first characteristics, when in the second orientation B. Accordingly, the sole 10 is readily adjustable between the first and second characteristics by movement of the bladder 14 with respect to the midsole 12. Further, it should be easily understood that the bladder 14 may be selectively fitted into the receptacle 18 in any one of the desired plurality of orientations, and is not limited to just the first and second orientations A and B.

The bladder 14 is movable with respect to the receptacle 18 between at least a supination orientation and a pronation orientation. Supination is described as the tendency to roll one's feet outward when striding, while pronation is described as the tendency roll one's feet inward when striding. To correct for these issues, the sole 10 can be stiffened in select regions to provide increased resistance against the undesired motion. For example, pronation can be addressed by orienting the bladder 14 to have the higher pressure second chamber 52 disposed on the medial side of the sole 10. Similarly, supination can be addressed by orienting the bladder 14 to have the higher pressure second chamber 52 disposed on the lateral side of the sole 10. During a stride, the center of the wearer's heel first strikes the center chamber 54, compressing the center chamber 54 and pushing at least a portion of the fluid into the connected second chamber 52. This, of course, increases the pressure within the second chamber 52. During a stride, the difference between the pressures P1 and P2 within the first and second chambers 50, 52 becomes greater, further enhancing the corrective ability of the bladder 14. FIGS. 13 and 14 show the sole 10 installed in a left article of footwear. In this illustration, the bladder 14 is installed in the “supination” orientation and the inflation of the second chamber 52 is exaggerated for illustrative purposes. Rotating the bladder 14 such that the second chamber 52 is disposed on the medial side of the sole 10 positions the bladder 14 in the “pronation” orientation.

The bladder 14 and the receptacle 18 may also include an alignment means for aligning the bladder 14 within the receptacle 18 in one of the plurality of orientations. In one embodiment, the bladder 14 and receptacle 18 may be shaped such that the bladder 14 fits into the receptacle 18 only in select orientations. For example, one of the bladder 14 and the receptacle 18 may include a key (not shown) and the other may include a plurality of slots that receive the key only when the bladder 14 is in one of the permissible orientations.

Referring back to FIG. 4, the midsole 12 and bladder 14 may include graphics, printed material or other symbols that assist in aligning the bladder 14. For example, the midsole 12 may be provided with an alignment indicator 60 (in this case, an arrow) and the bladder 14 may be provided with a plurality of similar alignment indicators 62 (in this case, a plurality of arrows) that show permissible orientations of the bladder 14. The bladder 14 may also include text or symbols that work in conjunction with the alignment indicators 60 and 62 to provide a visual indication of the results of the bladder 14 orientation. For example, the words “PRONATION,” “SUPINATION,” “REGULAR,” and “FIRM” may be printed on the insert adjacent to the appropriate alignment indicators 62.

Additionally, the center chamber 54 may be shallower than the first and second chambers 50, 52 and may be adapted to be fitted over a central post 36 located in the receptacle 18. The recessed center chamber 54 and central post 36 may help to assist in aligning and/or retaining the bladder 14 in the receptacle 18. The central post 36 may, however, be eliminated in favor of other configurations.

The sole 10 of FIGS. 1-14 is configured so that the bladder 14 is accessible from a top surface of the midsole 12, the bladder 14 being oriented atop the midsole 12. Thus, the midsole 12 and bladder 14 assembly may be removably fitted into an article of footwear, for example, by dropping the midsole 12 and bladder 14 assembly through the foot opening into the upper 11 and positioning it above the outsole 16. Referring now to FIGS. 15 and 16, alternatively, the midsole 12′ and bladder 14′ assembly may be oriented in the opposite position, with the bladder 14′ mounted to an underside of the midsole 12′.

The present invention may be incorporated into essentially any type of footwear, including but not limited to shoes, boots, sandals, slippers and athletic wear. Further, the present invention may be incorporated into essentially any footwear construction. For example, the sole construction may be incorporated into direct attach, welt, cement, stroble, California, opanka, lasted, slip lasted and other footwear constructions. The entire sole construction may be removably fitted into a void in an outsole, midsole or other sole component. Alternatively, select components of the present invention, such as the midsole and heel wedge, may be secured to the remainder of the sole. If an optional sock liner is included in the construction, it will typically be removable if its removal is necessary to provide access to the bladder.

The above description is that of the current embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular.

Claims

1. An article of footwear comprising: an upper; anda sole secured to the upper, the sole including a midsole having a receptacle and a flexible fluid-filled bladder fitted within the receptacle, the bladder being adjustable with respect to the midsole between at least first and second orientations, the bladder providing the sole with a first characteristic when in the first orientation, the bladder providing the sole with a second characteristic different from the first characteristic when in the second orientation, whereby the sole is readily adjustable between the first characteristic and the second characteristic by movement of the bladder with respect to the midsole.

2. The article of footwear of claim 1, wherein the bladder defines at least two discrete fluid chambers.

3. The article of footwear of claim 2, wherein the bladder includes a high pressure chamber and a low pressure chamber.

4. The article of footwear of claim 3, wherein the bladder further comprises a center chamber.

5. The article of footwear of claim 2, wherein the bladder is generally disc shaped and includes a substantially vertical axis, the bladder being movable between the first orientation and the second orientation by rotation about the axis.

6. The article of footwear of claim 5, wherein the receptacle includes an interface surface and the bladder includes an interface surface, wherein at least one of the receptacle interface surface and the bladder interface surface has projections extending therefrom for engaging the other of the receptacle interface surface and the bladder interface surface, wherein variations in the projections provide the sole with difference characteristics.

7. The article of footwear of claim 6, wherein the bladder interface surface has projections matingly engaging the projections on the receptacle interface surface.

8. The article of footwear of claim 7, wherein the projections on the bladder and on the receptacle are selected from the group consisting of undulations, ridges, and lobes.

9. The article of footwear of claim 4, wherein the chambers are filled with one of a gas, liquid, and a viscous gel.

10. A sole for an article of footwear comprising: a midsole including a receptacle; anda fluid-filled bladder received within the receptacle,wherein the bladder is adapted to be rotatably received within the receptacle in a plurality of orientations to provide a wearer's heel with a corresponding plurality of pressure distributions, whereby adjustment of a pressure distribution may be achieved by selectively fitting the bladder into the receptacle in a desired one of the plurality of orientations.

11. The sole of claim 10 wherein at least one of the plurality of pressure distributions is asymmetrical with respect to a midsole longitudinal centerline to correct one of pronation and supination in the wearer's step.

12. The sole of claim 10, wherein the fluid-filled bladder includes a center chamber and first and second peripheral chambers.

13. The sole of claim 12, wherein the first peripheral chamber includes a fluid at a first pressure and wherein the second peripheral chamber includes a fluid at second pressure different from the first pressure.

14. The sole of claim 12, wherein the center chamber is fluidly communicable with only one of the first and second peripheral chambers.

15. The sole of claim 10, wherein the receptacle includes an interface surface and wherein the bladder includes an interface surface, wherein at least one of the receptacle interface surface and the bladder interface surface includes projections extending therefrom for engaging the other of the receptacle interface surface and the bladder interface surface.

16. The sole of claim 10, wherein the receptacle further includes alignment indicator for aligning the bladder within the receptacle in one of the plurality of orientations.

17. An article of footwear comprising: an upper; anda sole secured to the upper, the sole including a midsole and a flexible fluid-filled bladder fitted within the midsole, the bladder having a substantially vertical axis and being adjustable with respect to the midsole between at least first and second orientations, the bladder providing the sole with first characteristics when in the first orientation and second characteristics, different from the first characteristics, when in the second orientation;wherein the midsole includes a receptacle for engagement with the bladder, the receptacle includes an interface surface with a plurality of projections, and the bladder includes an interface surface with a plurality of projections matingly engaged with the plurality of projections on the receptacle interface surface;wherein the bladder defines at least two discrete fluid chambers, and the bladder is movable with respect to the receptacle between at least a supination orientation to address problems associated with supination, a pronation orientation to address problems associated with pronation, a regular orientation, and a firm orientation.

18. The article of footwear of claim 17, wherein the bladder includes a first chamber containing fluid at a first pressure and a second chamber containing fluid at a second pressure that is higher than the first pressure.

19. The article of footwear of claim 18, wherein the bladder further comprises a center chamber.

20. The article of footwear of claim 19, wherein the center chamber is fluidly communicable with the second chamber.

21. A fluid-filled bladder for use with a footwear component comprising: a disc-shaped member being rotatable with respect to the footwear component, the disc-shaped member including first and second fluid-filled chambers, the first and second fluid-filled chambers being isolated from each other to define a first fluid pressure and a second fluid pressure, respectively, wherein the first fluid pressure is different from the second fluid pressure to provide a pressure distribution that varies with rotation of the disc-shaped member relative to the footwear component.

22. The fluid-filled bladder of claim 21 further including a central chamber interposed between the first and second chambers.

23. The fluid-filled bladder of claim 22 wherein the first and second chambers are semi-circular and are positioned radially outward of the central chamber.

24. The fluid-filled bladder of claim 22 wherein the central chamber is in fluid communication with the first chamber and isolated from the second chamber.

25. The fluid-filled bladder of claim 21 wherein the first and second chambers define a plurality of projections extending therefrom.

26. The fluid-filled bladder of claim 21 wherein the footwear component includes one of an insole, a midsole, and an outsole.

27. A footwear construction comprising: a footwear component; anda fluid-filled bladder adapted to interfit with the footwear component, the fluid-filled bladder including first and second fluid-filled chambers, wherein the fluid-filled bladder is rotatable with respect to the footwear component between a first orientation and a second orientation to provide a first pressure distribution and a second pressure distribution, respectively.

28. The footwear construction of claim 29 wherein the footwear component includes one of an insole, a midsole, and an outsole.

29. The footwear construction of claim 27 wherein the fluid-filled bladder is generally disc shaped and includes a plurality of projections.

30. The footwear construction of claim 27, wherein the first and second fluid-filled chambers are filled with one of a gas, a liquid, and a viscous gel.