Shoe sole structures using a theoretically ideal stability plane

• US 6,609,312 B1
• Filed: 12/03/1993
• Issued: 08/26/2003
• Est. Priority Date: 01/24/1990
• Status: Expired due to Term

• Current Assignee: Anatomic Research Inc.
• Original Assignee: Anatomic Research Inc.
• Inventors: Ellis, Frampton E. III
• Primary Examiner(s): Kavanaugh, Ted
• Application Number:
  US08/162,373
• Time in Patent Office: 3,553 Days
• Field of Search: 36/25.R, 36/30.R, 36/28, 36/31, 36/32.R, 36/88, 36/91, 361/14, 361/27, 361/29, 36/69
• US Class Current: 36/25.00R
• CPC Class Codes: A43B 13/143 provided with wedged, concave or convex end portions, e.g. for improving roll-off of the foot
• CPC Class Codes: A43B 13/145 Convex portions, e.g. with a bump or projection, e.g. 'Masai' type shoes
• CPC Class Codes: A43B 13/146 Concave end portions, e.g. with a cavity or cut-out portion

Abstract

A construction for a shoe, particularly an athletic shoe such as a running shoe, includes a sole that is constructed according to the applicant'"'"'s prior invention of a theoretically ideal stability plane. Such a shoe sole according to that prior invention conforms to the natural shape of the foot, particularly the sides, and that has a constant thickness in frontal plane cross sections; the thickness of the shoe sole sides contour equals and therefore varies exactly as the thickness of the load-bearing sole portion. The new invention relates to the use of the theoretically ideal stability plane concept to provide natural stability in negative heel shoe soles that are less thick in the heel area than in the rest of the shoe sole. This new invention also relates to the use of the theoretically ideal stability plane concept to provide natural stability in flat shoe soles that have no heel lift, maintaining the same thickness throughout; such a design avoids excessive structural rigidity by using contoured stability sides abbreviated to only essential structural support elements to provide the shoe sole with natural flexibility paralleling that of the human foot. The abbreviation of essential structural support elements can also be applied to negative heel shoe soles, again to avoid excessive rigidity and to provide natural flexibility.

Claims

1. A shoe sole comprising:

a sole portion having an inner, foot sole-contacting surface;

at least one contoured side portion, merging with the sole portion and having an inner, foot sole-contacting surface conforming to the curved shape of at least a part of one side of the sole of an intended wearer'"'"'s foot;

the shoe sole having a uniform thickness, when measured in frontal plane cross sections in all parts of the shoe sole intended to provide direct structural support between an intended wearer'"'"'s load-bearing foot sole, when inside the shoe, and ground;

the parts of the shoe sole intended to provide direct structural support between an intended wearer'"'"'s load-bearing foot sole and the ground include both that portion of the sole portion and that portion of the contoured side portion which become directly load-bearing when the shoe sole on the ground is tilted sideways, away from an upright position;

the uniform thickness of the shoe sole, as measured in a frontal plane cross section, extends through at least a contoured side portion intended to provide direct structural support between foot sole and ground through a sideways tilt of at least 30 degrees;

said shoe sole thickness being defined as the shortest distance bet ween any point on the inner, foot sole-contacting surface of said shoe sole and an outer surface of the parts of said shoe sole intended to provide direct structural support between an intended wearer'"'"'s load-bearing foot sole and the ground, when measured in a frontal plane cross section;

said sole portion having a greater thickness in a forefoot area than in a heel area when measured in a sagittal plane cross section; and

said thickness of the contoured side portion equaling and therefore varying directly with the thickness of the sole portion to which it is merged, when the thickness is measured in at least two frontal plane cross sections;

the uniform thickness of the shoe sole is different in at least two different frontal plane cross sections at locations where the shoe sole has a contoured side portion which is intended to provide direct structural support through a sideways tilt of the shoe sole of at least 30 degrees, so that there are at least two different contoured side portion thicknesses;

whereby, as measured in at least two frontal plane cross sections, the uniform thickness of the shoe sole, including the side portion, maintains a lateral stability of the intended wearer'"'"'s foot on the shoe sole like that when the intended wearer'"'"'s foot is bare on the ground, even during extreme sideways pronation and supination motion occurring when the shoe sole is in contact with the ground.

2. The shoe sole as set forth in claim 1, wherein said shoe sole is made of non-rigid material with sufficient flexibility to allow any portion, including a contoured portion, of the shoe sole directly between the load-bearing foot sole and the ground to deform by flattening under the wearer'"'"'s body weight load like the sole of an intended wearer'"'"'s foot when bare on the ground under substantially the same load;

as a result of the non-rigid material, the contoured shoe sole continues to conform to the shape of the wearer'"'"'s foot sole even when both are deformed by flattening in parallel under a body weight load; and

the flexibility of the shoe sole thereby maintains the flattened lower surface of the load-bearing foot sole at a substantially uniform distance from the ground, as viewed in a frontal plane cross section;

whereby the intended wearer'"'"'s contoured foot sole, when under a weight-bearing load on the ground, deforms to flatten on the upper surface of the flexible shoe sole in substantially the same manner as it would if the foot were bare on the ground surface, as viewed in a frontal plane cross section, since the shoe sole which is contoured in parallel with the foot sole flexes to deform in parallel with the foot sole, thereby providing a wide area of stable foot support contact.

3. The shoe sole as set forth in claim 1, wherein said contoured side portion merges with at least a sole portion proximate to the location of at least one of the following bones of an intended wearer'"'"'s foot when inside the shoe:

a head of the fifth metatarsal, a base of the fifth metatarsal, a lateral tuberosity of th e calcaneus, a base of the calcaneus, a head of the first metatarsal, and a head of the first distal phalange.

4. The shoe sole set forth in claim 1, wherein said contoured side portion merges with at least a sole portion proximate to the location of at least two of the following bones of an intended wearer'"'"'s foot when inside the shoe:

a head of the fifth metatarsal, a base of the fifth metatarsal, a lateral tuberosity of the calcaneus, a base of the calcaneus, a head of the first metatarsal, and a head of the first distal phalange.

5. The shoe sole as set forth in claim 1, wherein said contoured side portion merges with at least a sole portion proximate to the location of at least three of the following bones of an intended wearer'"'"'s foot when inside the shoe:

a head of the fifth metatarsal, a base of the fifth metatarsal, a lateral tuberosity of the calcaneus, a base of the calcaneus, a head of the first metatarsal, and a head of the first distal phalange.

6. The shoe sole as set forth in claim 1, wherein said contoured side portion merges with at least a medial sole portion proximate to the location of at least four of the following bones of an intended wearer'"'"'s foot when inside the shoe:

a head of the fifth metatarsal, a base of the fifth metatarsal, a lateral tuberosity of the calcaneus, a base of the calcaneus, a head of the first metatarsal, and a head of the first distal phalange.

7. The shoe sole set forth in claim 1, wherein said contoured side portion merges with at least a sole portion proximate to the location of at least five of the following bones of an intended wearer'"'"'s foot when inside the shoe:

a head of the fifth metatarsal, a base of the fifth metatarsal,a lateral tuberosity of the calcaneus, a base of the calcaneus, a head of the first metatarsal, and a head of the first distal phalange.

8. The shoe sole as set forth in claim 1, wherein said contoured portion merges with at least a sole portion proximate to the location of at least a head of the fifth metatarsal and a head of the first metatarsal of [the] an intended wearer'"'"'s foot when inside the shoe.

9. The shoe sole as set forth in claim 1, comprising at least two contoured side portions, one proximate to the location of the head of the first metatarsal and one proximate to the first distal phalange of an intended wearer'"'"'s foot when inside the shoe;

and said contoured side portions are separated by an area, including at least a frontal plane cross section, of the shoe sole extending through a sideways tilt of at least 30 degrees with no contoured side portion, said non-contoured side portion having a uniform thickness when measured in the frontal plane cross section included therein, in order to save weight and increase flexibility.

10. The shoe sole as set forth in claim 1, comprising at least two contoured side portions separated by a sole portion the sole portion being merged with a contoured side portion that has a thickness which is less than the thickness of the sole portion, in order to save weight and to increase flexibility;

the contoured side portion and sole portion thicknesses being measured in a frontal plane cross section.

11. The shoe sole construction as set forth in claim 1, comprising contoured side portions located at least at locations on the shoe sole proximate to the locations of the following support and propulsion elements of an intended wearer'"'"'s foot when inside the shoe:

a base and a lateral tuberosity of the calcaneus, a head of the first metatarsal, a head of the fifth metatarsal, a base of the fifth metatarsal, and a head of the first distal phalange, to thereby provide said shoe sole with flexibility and stability paralleling the foot sole flexibility and stability of an intended wearer'"'"'s foot.

12. The shoe sole as set forth in claim 1, wherein at least a substantial portion of the inner surface of said sole portion conforms to the contours of the sole of the load-bearing foot of the wearer.

13. The shoe sole construction as set forth in claim 1, wherein at least a substantial portion of the inner surface of said sole portion conforms to the contour of the bottom of an intended wearer'"'"'s foot sole when not under a load.

14. The shoe sole as set forth in claim 1, wherein the surface of said sole portion is substantially flat.

15. The shoe sole as set forth in claim 1, wherein the at least one contoured side portion with uniform thickness which is merged with said shoe sole portion, is sufficient to maintain lateral stability of an intended wearer'"'"'s foot throughout its full range of sideways motion by providing structural support directly between all portions of the intended wearer'"'"'s load-bearing foot sole and the ground, including at least at least 20 degrees of inversion of an intended wearer'"'"'s heel when inside the shoe;

the uniform thickness of the shoe sole extends through contoured side portions providing direct structural support at least beyond the load-bearing portions of the foot sole, so that the uniform thickness of the conforming shoe sole structure maintains a firm lateral stability substantially equivalent to that of an intended wearer'"'"'s foot when bare.

16. The shoe sole as set forth in claim 1, wherein the uniform thickness of the shoe sole extends through at least part of a contoured side portion providing direct structural support between an intended wearer'"'"'s foot sole, when inside the shoe, and ground through a sideways tilt of at least 45 degrees.