Flex limiting shoe sole

• US 4,779,361 A
• Filed: 07/23/1987
• Issued: 10/25/1988
• Est. Priority Date: 07/23/1987
• Status: Expired due to Term

• Current Assignee: Sam Kinsaul
• Original Assignee: Sam Kinsaul
• Inventors: Kinsaul, Sam
• Primary Examiner(s): Meyers, Steven N.
• Application Number:
  US07/076,960
• Time in Patent Office: 460 Days
• Field of Search: 36/33, 36/102, 36/30 R, 36/11.5, 36/44
• US Class Current: 36/102
• CPC Class Codes: A43B 13/141 with a part of the sole being flexible, e.g. permitting articulation or torsion
• CPC Class Codes: A43B 13/16 Pieced soles with several layers of different material A43B13/12

Abstract

A sole of a shoe provides for limiting the flex of the shoe. The sole includes a flexible portion positioned in the flexing area of the shoe corresponding to the ball of the wearers foot, a generally rigid front plate extending forward from the flexible portion, and a generally rigid rear plate extending rearward from the flexible portion. Further, a flexible banding or strapping layer is provided for underlying the flexible portion and at least part of the front and rear plates. The flexible strapping layer is fixed to the flexible portion and to the plates to maintain the positional relationship therebetween. Further, the flexible portion includes a plurality of generally laterally extending rigid slats. In a cross-sectional view, each of the generally laterally extending rigid slats has a top, a bottom, and opposing side shoulders. The bottom is affixed directly to the strapping layer. At least one of the shoulders is tapered toward the top such that when the flexible portion is flexed, adjacent shoulders of adjacent slats bear upon one another after a predetermined range of flexing, thus limiting any further longitudinal flex of the flexible portion.

Claims

1. A sole of a shoe for limiting the flex of the shoe, comprising:

a flexible portion positioned in a flexing area of the shoe corresponding to the ball of the wearer'"'"'s foot;

a generally rigid front plate, extending forward from said flexible portion;

a generally rigid rear plate, extending rearward from said flexible portion; and

a flexible strapping layer underlying said flexible portion and at least part of said front and rear plates, and fixed to said plates and flexible portion to maintain the positional relationship therebetween and to provide tensile strength form said flexible portion during flexing;

wherein said flexible portion includes a plurality of generally laterally extending rigid slats, each slat having a top, a bottom, and opposing side shoulders in a longitudinal cross-sectional view, and wherein the bottom of each slat is fixed to said strapping layer, and at least one of said shoulders is tapered toward said top, such that when said flexible portion is flexed, adjacent shoulders of adjacent slats bear upon one another after a predetermined range of flexing, thus limiting the flex of said flexible portion in the longitudinal direction to a predetermined limit.

2. The sole of claim 1, wherein said front plate extends all the way to the front of the shoe.

3. The sole of claim 1, wherein both shoulders of each slat are tapered toward the top thereof.

4. The sole of claim 1, wherein said slats have rounded corners when viewed from said longitudinal cross-sectional view.

5. The sole of claim 1, wherein each slat has a protrusion on one shoulder, and an indentation on the opposing shoulder thereof, such that when adjacent shoulders bear upon one another at the flex limit, a protrusion from one shoulder mates with an indentation from an adjacent shoulder.

6. The sole of claim 1, wherein a protective cover is disposed on top of said slats.

7. The sole of claim 1, wherein said sole is positioned between an inner sole and a traction layer.

8. The sole of claim 1, wherein said strapping layer comprises the traction layer of the shoe.

9. The sole of claim 1, wherein the length of each of said slats is the same as the width of said front plate.

10. The sole of claim 1, wherein said rear plate extends only part of the way to the rear of the shoe, and an end layer of pliable material extends from the end of said rear plate to the rear end of the shoe.

11. The sole of claim 1, wherein said sole includes flexibility grooves positioned generally longitudinally with respect to said sole.

12. The sole of claim 11, wherein said front plate, said flexible portion and said rear plate, all include said longitudinal flexibility grooves, wherein the grooves are narrow at the bottom thereof and wide at the top such that upon lateral flexing of the sole, said grooves disappear, thus increasing the lateral flexibility of the sole.

13. The sole of claim 1, wherein said generally rigid front plate includes a forward flexible portion including several generally laterally extending rigid front slats, and wherein said front slats include a limiting means for limiting the flex of said forward flexible portion in the longitudinal direction to a predetermined limit.

14. The sole of claim 13, wherein said limiting means comprises said several front slats wherein each front slat has a top, a bottom, and opposing side shoulders in a longitudinal cross-sectional view, and wherein the bottom of each front slat is fixed to said strapping layer, and at least one of said shoulders is tapered toward said top, such that when said forward flexible portion is flexed, adjacent shoulders bear against one another to limit the flex thereof.

15. The sole of claim 1, wherein said shoe is an athletic shoe.

16. The sole of claim 1, wherein the widest portion of each slat, when viewed in a longitudinal cross-section, is substantially at the bottom of the slat, where the slat is fixed to said strapping layer.