Footwear fluid-filled chamber having central tensile feature
An article of footwear includes a sole structure including a chamber for receiving a pressurized fluid, the chamber having a top portion, a bottom portion, and side portions around a periphery of the chamber. The sole structure also includes a central structure located in a central portion of the chamber between opposing side portions of the chamber, such that the chamber is devoid of additional structures in a surrounding region around the central structure and extending from the central structure to the side portions of the chamber. On all sides of the central structure, a dimension of the surrounding region between the central structure and the nearest side portion is one third or more of a span across the chamber between opposing side portions.
1 . An article of footwear having an upper and a sole structure secured to the upper, the sole structure comprising:
a chamber defining an interior void for receiving a pressurized fluid, the chamber having a top portion, a bottom portion, and a side portion extending between the top portion and the bottom portion around a periphery of the chamber;
a central structure including a continuously bonded area where the top portion of the chamber is joined to the bottom portion of the chamber to form a recess in the top portion of the chamber, the recess extending from a top of the chamber past a midpoint of a thickness of the chamber; and
a reinforcing member including an upper portion having a lower surface bonded to the top portion of the chamber and a support structure extending downward into the recess in the top portion of the chamber, the support structure including a plurality of progressively narrower steps extending from the lower surface to a distal end of the support structure and including a variable cross-section, each step of the plurality of progressively narrower steps having a first planar surface facing the upper and a second planar surface defining an outer periphery of the step, the first planar surface being perpendicular to the second planar surface.
2 . The sole structure of claim 1 , wherein the reinforcing member comprises a material selected from a composite material, polyurethane, or vinyl.
3 . The sole structure of claim 1 , wherein the upper portion of the reinforcing member comprises a rigid plate and the support structure is formed from a compressible material.
4 . The sole structure of claim 1 , wherein the support structure tapers in a direction from the upper portion toward the central structure.
5 . The sole structure of claim 1 , wherein the plurality of progressively narrower steps become progressively narrower in a direction from the upper portion toward the central structure.
6 . The sole structure of claim 1 , wherein the support structure includes a central member and a plurality of peripheral members arranged around the central member.
7 . The sole structure of claim 6 , wherein at least one of the central member and the plurality of peripheral members is cylindrical.
8 . The sole structure of claim 6 , wherein peripheral members of the plurality of peripheral members are smaller than the central member.
9 . The sole structure of claim 1 , wherein one or more peripheral members includes an inverted frustoconical upper portion that cooperates with a frustoconical lower portion to provide the one or more peripheral members with an hourglass shape.
10 . The sole structure of claim 1 , wherein each step of the plurality of progressively narrower steps has a planar anterior surface facing a forefoot region of the sole structure and an arcuate posterior surface opposite the planar anterior surface.
11 . An article of footwear having an upper and a sole structure secured to the upper, the sole structure comprising:
a chamber defining an interior void for receiving a pressurized fluid, the chamber having a top portion, a bottom portion, and a side portion extending between the top portion and the bottom portion around a periphery of the chamber;
a central structure including a continuously bonded area where the top portion of the chamber is joined to the bottom portion of the chamber to form a recess in the top portion of the chamber, the recess extending from a top of the chamber past a midpoint of a thickness of the chamber; and
a reinforcing member including an upper portion having a lower surface bonded to the top portion of the chamber and a support structure extending downward into the recess in the top portion of the chamber, the support structure including a plurality of progressively narrower steps extending from the lower surface to a distal end of the support structure and tapering in a direction from the upper portion toward the central structure, each step of the plurality of progressively narrower steps having a first planar surface facing the upper and a second planar surface defining an outer periphery of the step, the first planar surface being perpendicular to the second planar surface.
12 . The sole structure of claim 11 , wherein the reinforcing member comprises a material selected from a composite material, polyurethane, or vinyl.
13 . The sole structure of claim 11 , wherein the upper portion of the reinforcing member comprises a rigid plate and the support structure is formed from a compressible material.
14 . The sole structure of claim 11 , wherein the support structure includes at least one void.
15 . The sole structure of claim 11 , wherein the support structure is hollow.
16 . The sole structure of claim 15 , wherein the support structure includes a wall defining a shape of the support structure, the wall including at least one perforation formed therethrough.
17 . The sole structure of claim 11 , wherein the plurality of progressively narrower steps become progressively narrower in the direction from the upper portion toward the central structure.
18 . The sole structure of claim 11 , wherein the support structure includes a central member and a plurality of peripheral members arranged around the central member.
19 . The sole structure of claim 18 , wherein at least one of the central member and the plurality of peripheral members is cylindrical.
20 . The sole structure of claim 11 , wherein each step of the plurality of progressively narrower steps has a planar anterior surface facing a forefoot region of the sole structure and an arcuate posterior surface opposite the planar anterior surface.