Modular insert system for shoe soles

Abstract

A support customising system is described for a sole of a shoe. The sole includes a relatively soft, resilient midsole and an a harder outsole. Hard insert elements are provided for inserting into vertical cavities in the midsole. By varying the hardnesses of different inserts in different vertical cavities, a precisely-tunable pronation control effect on the wearer's gait can be effected. First-order, second-order and third-order pronation control effects are described. Measures are provided for improving the accuracy of the proprioceptive (sensory motoric) effect on the wearer's foot, for example by limiting the ingress of dirt or water.

1 . An article of footwear, comprising:
 a sole comprising a midsole part of a first material having a first durometer, the midsole having an upper, foot-facing surface and a lower, ground-facing surface,   an outsole part, below the lower surface of the midsole, the outsole having a second durometer,   a plurality of cavities in a first region of the midsole, each cavity extending along a vertical axis substantially orthogonally to the upper surface, between the lower and the upper surfaces of the midsole, and   a plurality of support adjustment elements, each of which is substantially wholly inserted into one of the vertical cavities so as to adjust a vertical support hardness of the sole at the location of said each vertical cavity;   wherein each vertical cavity comprises an insertion opening in the lower surface for receiving one of the support adjustment elements such that the adjustment element extends through the outsole;   wherein the plurality of support adjustment elements comprises a first support adjustment element having a third durometer and a second support adjustment element having a fourth durometer, different from the third durometer, wherein at least one of the third and fourth durometers is greater than the first durometer; and   wherein each of the adjustment elements comprises a body part for being inserted into the cavity and a lower part, wider than the body part, bonded to or located in an opening of the outsole.   
     
     
         2 . The footwear according to  claim 1 , wherein the second durometer is greater than the first durometer. 
     
     
         3 . The footwear according to  claim 1 , wherein the fourth durometer is different from the third durometer, and wherein at least one of the third and fourth durometers is greater than the first durometer. 
     
     
         4 . The footwear according to  claim 1 , wherein each of the first and second support adjustment elements, when inserted into a first one of the vertical cavities, and the plurality of vertical cavities have substantially the same cross-section as the first vertical cavity in a horizontal plane parallel to the upper and or lower surface, such that the first and second support adjustment elements are interchangeably insertable into the first vertical cavity through the insertion opening of the first vertical cavity. 
     
     
         5 . The footwear according to  claim 1 , wherein the first support adjustment element, the second support adjustment element and a first one of the plurality of vertical cavities have substantially the same vertical length along the vertical axis. 
     
     
         6 . The footwear according to  claim 1 , wherein the first and second support adjustment elements and the plurality of vertical cavities each has a substantially constant cross-section along at least a majority of its vertical length. 
     
     
         7 . The footwear according to  claim 1 , wherein the first and/or second support adjustment elements comprise a sensory-motoric stimulus protrusion configured to extend up to or protrude proud of the upper surface of the midsole, so as to provide a sensory-motoric load-response stimulus to a wearer's foot at the location of the said first or second support adjustment element. 
     
     
         8 . The footwear according to  claim 1 , wherein the first and/or second support adjustment elements protrude proud of the lower surface of the outsole. 
     
     
         9 . The footwear according to  claim 1 , wherein a first plurality of vertical cavities is arranged in a first gait control region of the sole, and a second plurality of the vertical cavities is arranged in a second gait control region of the sole. 
     
     
         10 . The footwear according to  claim 9 , wherein the first and second pluralities of vertical cavities and the plurality of support adjustment elements have substantially the same cross-section, such that the first plurality of support adjustment elements can be fittedly inserted into the vertical cavities of the first and second pluralities. 
     
     
         11 . The footwear according to  claim 1 , in which the third durometer is at least 5 Shore greater than the first durometer, where the fourth durometer is at least 5 Shore greater than the third durometer and/or in which the third durometer is less than or equal to the first durometer. 
     
     
         12 . The footwear according to  claim 1 , in which the lower part  5 ′ of the adjustment element extends laterally on average by at least 5% of the width of the body part wider than the opening of the cavity  2  into which it is inserted. 
     
     
         13 . The footwear according to  claim 12 , in which the lower part  5 ′ extends laterally on average at least 2 mm, or at least 4 mm wider than the opening, and/or on average at most 6 mm wider than the body part. 
     
     
         14 . The footwear according to  claim 1 , wherein the material of the midsole comprises a polyurethane material, and/or wherein the material of the body part of each adjustment element comprises a polyurethane material, and/or wherein the material of the outsole part of each adjustment element comprises a polyurethane material. 
     
     
         15 . The footwear according to  claim 1 , wherein each adjustment element is provided with a retention element for retaining a body part of the adjustment element in the midsole. 
     
     
         16 . The footwear according to  claim 1 , wherein the retention element is a pin, insertable transversely through the midsole and the body part. 
     
     
         17 . A method of manufacturing a sole for an article of footwear according to  claim 1 , the method including:
 forming the midsole element by vacuum-moulding the material of the midsole element around formers arranged for forming the cavities with opening to the lower surface of the midsole element.   
     
     
         18 . The method according to  claim 17 , wherein the material of the midsole element comprises a polyurethane foam. 
     
     
         19 . A method of customising the footwear of  claim 1 , so as to control the support provided to a wearer's foot by the sole, the method comprising the steps of:
 determining a support requirement of the wearer's foot,   based on the support requirement, selecting said first and second support adjustment elements from said plurality of support adjustment elements,   based on the support requirement, selecting said first vertical cavity, wherein the first vertical cavity is located in a third gait control region for adjusting the support provided by the sole to the wearer's foot for meeting the support requirement, inserting one of the first and second support adjustment elements into said first vertical cavity.   
     
     
         20 . The method according to  claim 19 , further comprising the step of inserting the other of the first and second support adjustment elements into a second vertical cavity in said third gait control region or in a fourth gait control region, different from the third gait control region.