Abstract:
A shoe sole presenting a rear portion in turn presenting at the top a number of inclined, flexible transverse ribs defining a deformable heel support.

Description:
This is a continuation application of Ser. No. 08/597,260, filed on Feb. 6, 1996, now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a shoe sole, in particular for sports shoes such as hiking boots, or for casuals or walking shoes. 
     Sports shoes are known to feature soles made of rubber and comprising, integrally, a front or toe portion, and a rear or heel portion, which is generally higher than the front portion to define a raised heel supporting surface. 
     To reduce the weight of the shoe, the rear portion is frequently hollow at the top, and the cavity defined by the raised edge houses a number of transverse and longitudinal ribs which intersect to form a grid pattern. 
     The edge of the cavity and the ribs are flush at the top to form a supporting surface for a mid-sole. 
     A major drawback of known shoe soles is the rigidity of the rear portion supporting the heel, which results in discomfort and, in the case of prolonged wear, in undue fatigue and even inflammation of the foot. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a shoe sole, particularly for sports shoes, designed to overcome the above drawback. 
     According to the present invention, there is provided a shoe sole comprising, integrally, a rear heel supporting portion and a front toe supporting portion; characterized in that at least said rear portion presents deformable supporting means at the top. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A preferred, non-limiting embodiment of the present invention will be described by way of example with reference to accompanying drawings, in which: 
     FIG. 1 shows a top plan view of a shoe sole in accordance with the of the present invention; 
     FIG. 2 shows an enlarged partial section along line II--II in FIG. 1. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Number 1 in FIG. 1 indicates a sole for a sports shoe, in particular a hiking boot. 
     As shown in FIGS. 1 and 2, sole 1 is made of rubber, and presents an upper face 2 designed to mate with a mid-sole; and a lower face 3 with a tread 4 designed to rest on the ground. 
     Upper face 2 is defined peripherally by a concave edge 5. 
     Sole 1 comprises, integrally, a front or toe portion 6; a rear or heel portion 7; and an intermediate portion 8 corresponding with the arch of the foot. At intermediate and rear portions 8 and 7, sole 1 presents, at the top, a cavity 9 defined laterally by raised edge 5, and in which are formed a central longitudinal rib 10 extending the full length of cavity 9, and a number of transverse ribs 11 extending between opposite lateral portions of edge 5, and which are flush at the top with edge 5, and intersect longitudinal rib 10 to form a grid pattern. 
     According to the present invention, longitudinal rib 10 in rear portion 7 is smaller in height, so that each transverse rib 11 presents an end portion 12 projecting upwards in relation to longitudinal rib 10, and which is deformable by the foot to act as a damper. 
     With the exception of the last one adjacent to the rear end 13 of sole 1, said ribs 11 slope upwards towards rear end 13 in relation to a vertical plane crosswise to sole 1. 
     When walking, projecting portions 12 of transverse ribs 11 flex towards rear end 13 of sole 1 under the pressure exerted by the heel when the foot is set down, and spring back to the undeformed position when thrust is exerted by the front portion of the foot. As such, rear portion 7 acts as a damper, i.e. shock absorber, for safeguarding against injury to the heel or Achilles tendon. 
     Moreover, according to the preferred embodiment of the invention described above, said function is achieved while maintaining the necessary height of rear portion 7, and with no reduction in the rigidity of sole 1. 
     Clearly, changes may be made to the sole as described and illustrated herein without, however, departing from the scope of the present invention. 
     For example, end portions 12 of transverse ribs 11 may slope towards intermediate portion 8 as opposed to rear end 13. 
     Sole 1 may also be applied to any type of shoe, e.g. sports shoes, casuals or walking shoes.