Split sole independently adjustable load-limiting footwear

Abstract

A force absorbing device for a footwear appliance includes a shoe upper and a shoe sole having a planar sole surface, such that forces between the shoe upper and planar sole surface in ground contact are absorbed by storage and controlled release of kinetic energy in an elastic or resilient field. A footwear article such as a shoe or boot includes a split-sole system that redefines a shoe sole as coplanar surfaces having a force mitigating interface for receiving sudden forces and effectively mitigating these forces by storing kinetic energy and releasing it over time. An elastic field in the force mitigation interface is defined by a resilient material adapted to deform in response to the received force. Frictional engagement between the upper and lower sole may also be augmented by surface characteristics such as dimples, voids and lubricants, in addition to interference engagement with an elastic field.

What is claimed is: 
     
         1 . In a footwear appliance for mitigating injurious forces, a force absorbing shoe sole, comprising:
 a footbed configured for engagement with a foot of a wearer;   an outsole in communication with a ground or floor surface; and   a midsole, the midsole disposed between the footbed and the outsole, the midsole engaged with the outsole through at least one force mitigation coupling for accommodating lateral displacement between the midsole and the outsole,   the outsole having a heel portion and a toe portion, the heel portion and the toe portion having separate respective engagements with the midsole for independent movement.   
     
     
         2 . The method of  claim 1  wherein the force mitigation coupling includes an actuator disposed in an elastic field, the actuator attached to the midsole and the elastic field embedded in the outsole. 
     
     
         3 . The method of  claim 1  further comprising a plurality of the force mitigation couplings, including:
 at least one force mitigation coupling between the heel portion and the midsole; 
 at least one force mitigation coupling between the toe portion and the midsole, 
 each of the force mitigation couplings defined by an actuator adapted for slidable movement compressing an elastic field. 
 
     
     
         4 . The method of  claim 3  wherein the actuator is a rigid material and the elastic field is a resilient, compressible material, the elastic field exerting a force with a component in a direction perpendicular to a direction of compression exerted by the actuator. 
     
     
         5 . The method of  claim 3  wherein the actuator has a compressive surface oriented at an angle to a direction of translation across the elastic field, the angle exerting a compressive force on the elastic field in a direction perpendicular to the direction of translation. 
     
     
         6 . The method of  claim 3  wherein the force mitigation couplings provide independence of responsive movement of the actuator in the fore, aft, left, right and rotational directions. 
     
     
         7 . The method of  claim 3  further comprising:
 a plurality of arms extending from the actuator, each of the arms extending in an arm direction and having an area based on a responsive force to translation in the arm direction from the elastic field. 
 
     
     
         8 . The method of  claim 3  further comprising a circumferential elastic field. 
     
     
         9 . The method of  claim 3  further comprising a modular elastic field. 
     
     
         10 . The method of  claim 7  further comprising rotational guides, the rotational guides defined by portions of the elastic field offset from an arm direction of the plurality of arms, the rotational guides disposed for actuator contact resulting from a rotation or a component of movement aligned with two or more of the arm directions from the arms. 
     
     
         11 . The method of  claim 7  further comprising rotational flaps, the rotational flaps defined by portions of the elastic field extending upright and adapted for fold towards horizontal in response to actuator movement. 
     
     
         12 . The method of  claim 1  further comprising:
 a recession in the toe portion; 
 a recession in the heel portion; 
 each of the recessions configured to contain a force mitigation module defining the force mitigation coupling; and 
 an attachment of the actuator of each of the force mitigation modules to the midsole for mitigating forces between the midsole and the outsole.