Patent Application
20130318828
Walking, jogging and running are forms of bipedal motion that cause varying levels of stress on a person's legs and feet. As a result, shoe manufacturers add cushions and supports to shoes to provide comfort and to absorb impact forces generated by the repeated contact of a person's feet with the ground when performing these activities.
Shoes have different supports and support structures depending on the type of activity. For example, walking shoes do not require as much support as running shoes due to the fact that running generates greater stress and impact on a person's legs and feet during running. Cushions and supports in shoes are configured to relieve the impact stress on a person's body resulting from different running conditions. Overpronation is a running condition where a foot rolls inwardly such that the inner or medial portion of the foot absorbs a majority of the impact stress. In contrast, underpronation occurs when the impact stress is mainly on the outer or lateral portion of the foot where the foot does not roll inwardly. Both of these types of running conditions are corrected by providing more cushioning and support to the shoes at the areas of the foot that absorb a majority of the impact stress. Adding cushioning and supports to shoes to account for different running conditions, increases the manufacturing cost of the shoes and ultimately increases the cost of shoes for consumers. Also, users must purchase different shoes for different bipedal motion activities and to overcome different running conditions, which significantly increases the costs associated with those activities.
An article of footwear is provided that includes a two-part sole that divides and deflects impact forces due to bipedal motion and provides support at both the medial and lateral sides of the article of footwear to reduce the effects of multiple running conditions such as overpronation and underpronation.
In an embodiment, a sole for an article of footwear is provided that includes a first part having a bottom surface with a plurality of first protrusions increasing in thickness from a medial side to a lateral side, where each adjacent pair of the first protrusions define a first recess therebetween, and a second part having a top surface with a plurality of second protrusions increasing in thickness from a lateral side to a medial side, where each adjacent pair of the second protrusions defines a second recess therebetween. When the first part (firmer material) and the second part (softer material) are attached together, the plurality of first protrusions and recesses on the bottom surface of the first part matingly engage corresponding ones of the plurality of second protrusions and recesses on the top surface of the second part to form a sole that deflects and absorbs impact forces resulting from multiple running conditions.
In another embodiment, an article of footwear is provided that includes an upper and a midsole attached to the upper, where the midsole includes a first part and a second part. The first part includes a top surface and a bottom surface where the bottom surface includes a plurality of first protrusions increasing in thickness from a medial side to a lateral side and each adjacent pair of the first protrusions define a first recess therebetween. The second part includes a top surface and a bottom surface, where the top surface includes a plurality of second protrusions increasing in thickness from a lateral side to a medial side and each adjacent pair of the second protrusions define a second recess therebetween. When the first part and the second part are attached together, the plurality of first protrusions and recesses on the bottom surface of the first part matingly engage corresponding ones of the plurality of second protrusions and recesses on the top surface of the second part. The bottom surface of the second part includes a plurality of tread members or angled cleats, where a rear portion of each tread member is taller or thicker than a front portion of the tread member. Each of the tread members is positioned directly adjacent to the thickest portion of one of the second protrusions to allow the tread member to bend or push into the second protrusion upon impact with the ground to absorb the shock generated by the impact.
The present footwear sole includes two mating parts that combine to divide, absorb and deflect shock from impact forces resulting from bipedal motion activities, such as walking, jogging and running, to substantially reduce the effect of impact forces caused by multiple running conditions.
Referring now to
The upper part or midsole 16 has a top surface 20 and an opposing side or bottom surface 22 where the first part is preferably made of ethylene vinyl acetate (EVA) and is formed to generally follow the shape of a person's foot. The top surface 20 is generally flat and is attached to the upper 12 by adhesive. It should be appreciated that any suitable attachment method may be used to attach the first part or midsole to the upper 12. The bottom surface 22 of the first part 20 includes a plurality of first triangular-shaped protrusions or supports 24 formed by angled surfaces 26 that increase in thickness from a medial side 28 to a lateral side 30. It should be appreciated that the angled surfaces 26 may be at any suitable angle relative to the bottom surface 22. In the illustrated embodiment, the first supports 24 are separated by corresponding first triangular-shaped grooves or recesses 32. As shown in
Referring now to
Referring now to
The second part 18 also includes two spaced, elongated longitudinal protrusions or supports 48 that each extend generally longitudinally between the toe and heel portions 34, 36 as shown in
To enhance traction with the ground, the second part 18 includes a plurality of tread members 50 that extend from the bottom surface 42 of the second part 18. Each of the tread members 50 has a generally triangular shape with an angled front portion 52 and a generally straight, rear portion 54. The angled front portion 52 of each tread member 50 includes a plurality of steps or stepped surfaces 56. As shown
Referring now to
The first and second parts 16, 18 of the present sole 10 fit together such that the first protrusions 24 of the first part 16 matingly engage the corresponding second grooves 26 of the second part 18 and the second protrusions 44 of the second part 18 matingly engage the corresponding first recesses 32 of the first part 16. The combination of the first and second parts 16, 18 of the sole 14 provide firm support at the inner or medial side 28 of a shoe to reduce the impact stresses from overpronation, and cushioning at the outer or lateral side 30 of the shoe for absorbing impact stresses due to underpronation. Further, the present sole 14 divides and deflects the shock generated by the impact forces so that less of the shock is transferred to a wearer's feet and legs. Thus, the present two-part sole 14 allows for great traction and stability on soft surfaces while transitioning to substantial cushioning and support on firm surfaces. The present two-part sole 14 also requires less parts, such as cushioning layers, than conventional shoes, which reduces the complexity and the weight of the shoe while providing support and stability to wearers.
While a particular embodiment of the present article of footwear has been described herein, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects.
