Patent ID: 6789333
Filing Date: 2004-09-14
Classification: A43B

Abstract:
A midsole including a cushioning structure, which is provided between an outer sole and an upper and is suitable for absorbing a shock of landing, comprising:a midsole body defining a cavity; and a cushioning part fitted in the cavity, wherein: the cushioning part is formed of elastomer; Young modulus of a member constituting the cushioning part is set to be a value smaller than Young modulus of a member constituting the midsole body; the cushioning part includes a through hole passing through the cushioning part from its upper surface to its lower surface, whereby the cushioning part is formed into a ring shape having an outer peripheral surface and an inner peripheral surface; a plurality of first grooves is formed on the outer peripheral surface of the cushioning part; a plurality of second grooves is helically formed on the inner peripheral surface of the cushioning part; the respective first grooves are helically formed around a substantially vertical axial line; the respective first grooves are arranged substantially parallel with each other; and a range in which each of the grooves is formed is larger than a range of 15 degrees around the axial line and smaller than a range of 180 degrees around the axial line.