Traction lug for footwear

Abstract

A lug for a sole or outsole of a footwear, i.e. a shoe or a boot, which is able to improve the traction or grip features of the sole itself; sole or outsole equipped with a plurality of lugs and a method for obtaining a mold cast printed with a 3D printing machine to obtain the sole and/or the lugs.

1 . A lug for a sole or outsole of a footwear, for example shoe, a sport shoe or a work footwear or a boot, wherein said lug comprises a first base, a second base and a sidewall, wherein said first base is suitable to contact the ground during use, said second base is suitable to be attached to the sole or outsole and/or it is opposite to said first base and said sidewall is suitable to connect laterally said first base and said second base, wherein said lug comprises features and/or elements at least at a part of said sidewall able to confer to said lug traction and grip on grounds or terrains consisting of granular particulates or penetrable surfaces, wherein said features and/or elements comprise at least one protrusion and/or at least one indentation, wherein said at least one protrusion has a prismatic shape and is constituted by faces, each face or at least one face thereof having a rectangular shape, a square shape, or a trapezoidal shape. 
     
     
         2 . The lug according to  claim 1 , wherein said at least one protrusion is separated by at least one channel, which extension is horizontal or parallel to the ground, and/or by at least one slit, which extension is vertical or parallel to the direction from ground to the sole. 
     
     
         3 . A lug for a sole or outsole of a footwear, for example shoe, a sport shoe or a work footwear or a boot, wherein said lug comprises a first base, a second base and a sidewall, wherein said first base is suitable to contact the ground during use, said second base is suitable to be attached to the sole or outsole and/or it is opposite to said first base and said sidewall is suitable to connect laterally said first base and said second base, wherein said lug comprises features and/or elements at least at a part of said sidewall able to confer to said lug traction and grip on grounds or terrains consisting of granular particulates or penetrable surfaces, wherein said features and/or elements comprise at least one protrusion and at least one indentation, wherein said at least one protrusion and said at least one indentation are alternate the one with respect to the other, thus forming a zig-zag pattern or a crests-and-valleys conformation. 
     
     
         4 . The lug according to  claim 2 , wherein said protrusions and said indentations are placed longitudinally, i.e. they are parallel or inclined with respect to the side-to-side orientation of the foot of the user, and/or they are substantially parallel to the ground and/or they have an elongated and/or rectilinear conformation. 
     
     
         5 . The lug according to  claim 1 , wherein each lug has a front face, substantially orientated towards the front of the sole, and one back face, orientated towards the rear or heel of the sole, and said at least one protrusion and/or said at least one indentation is placed on said front face and/or on said back face. 
     
     
         6 . The lug according to  claim 1 , wherein said at least one channel and/or said a least one slit has a transversal section having V-, U- or square shape, possible with vertex or smaller portion towards the inside of the lug and/or wherein said at least one slit is substantially perpendicular to said at least one channel or to said at least one indentation and/or wherein said at least one slit crosses said at least one channel in a sort of grid or net, determining the formation of said at least one protrusion. 
     
     
         7 . The lug according to  claim 1 , wherein said features and/or elements increase the surface area of said sidewall and/or wherein said features and/or elements are present at said first base of said lug and increase the surface area of said first base. 
     
     
         8 . The lug according to  claim 1 , wherein said sidewall comprises at least one step or wherein said sidewall is not stepwise or has not a step or is smooth. 
     
     
         9 . The lug according to  claim 1 , wherein said lug has a substantially prismatic, cubic or parallelepiped or frustum of pyramid conformation, with said first base and said second base shaped substantially as a triangular, a rectangle, a square, a trapezoid, hexagon, regular or irregular. 
     
     
         10 . The lug according to  claim 1 , wherein said lug has a V-like shape in top plan view and said first base and said second base have a V-like shape in top plan view or wherein said lug has a substantially cylindrical, hemispherical, tetrahedral, semi-ellipsoidal, frustum of cone or frustum of pyramid, regular, irregular, L-like, C-like shape, and said first base and second base have a square, rectangular, polygonal, parallelogram, regular, irregular, L-like, C-like or trapezoidal shape. 
     
     
         11 . The lug according to  claim 1 , wherein said first base is smaller in size than said second base and said sidewall is inclined and/or tapered in use towards a common point of the ground and/or wherein said sidewall comprises faces inclined in use towards a common point of the ground and/or wherein said first base is parallel or not parallel with respect to said second base. 
     
     
         12 . The lug according to  claim 1 , wherein said first base and said second base have the same size, and they are substantially superimposed the one with the other, whereby said sidewall is substantially perpendicular to said first base and/or to said second base. 
     
     
         13 . The lug according to  claim 1 , wherein said first base and said second base have the same size, but they are offset one with respect to the other and said sidewall is inclined in use towards the ground along a same direction and/or wherein said sidewall comprises faces inclined in use towards the ground along a same direction. 
     
     
         14 . The lug according to  claim 8 , wherein said at least one step has sharp or rounded edges and/or it has right-angled edges and/or wherein each step, when more than one step is present, has substantially the same size. 
     
     
         15 . The lug according to  claim 1 , wherein said at least one protrusion comprises a protruding shape and a base, wherein said base is attached to said sidewall and/or to said step and said protruding shape is a substantially semispherical shape or a faceted semi-sphere, or pyramidal, frustum of pyramid, frustum of cone, conical, and/or with a square, rectangular, polygonal, parallelogram, regular, irregular, L-like shaped, C-like shaped, or trapezoidal base. 
     
     
         16 . The lug according to  claim 1 , wherein said at least one indentations comprises an intruding shape and a base, wherein said base is placed at said sidewall and/or at said step and said intruding shape is a substantially semispherical shape or a faceted semi-sphere, or pyramidal, frustum of pyramid, frustum of cone, conical, spike, diamond or prismatic shape, a parallelepiped or rectangular prism, cylindrical, hemispherical, tetrahedral, semi-ellipsoidal, and/or with a square, rectangular, polygonal, parallelogram, regular, irregular, L-like shaped, C-like shaped, or trapezoidal base. 
     
     
         17 . The lug according to  claim 1 , wherein said lugs, which are placed at at least one portion of the perimeter of the sole, have at least one smooth side face, which is facing the perimeter of the sole, said front face and said back face extending towards the inside or middle point of the sole. 
     
     
         18 . A sole of a footwear, for example an outsole of a shoe, a sport shoes or a work footwear or a boot, wherein said sole comprises an upper surface, adapted in use to face toward the foot of a user, and a lower surface, adapted in use to face toward the resting surface or the ground, wherein said lower surface comprises at least one and/or a plurality of lugs according to  claim 1 . 
     
     
         19 . The sole according to  claim 18 , wherein said lower surface is directly attached, for example by means of a unique molding step, with said at least one lug and/or said plurality of lugs, for example at said second base of said lug. 
     
     
         20 . The sole according to  claim 18 , wherein said lower surface comprises at least one protrusions and/or at least one indentations. 
     
     
         21 . A method for obtaining a mold for the production of a sole according to  claim 18 , comprising the following steps:
 determine, by creating a digital file, a bi-dimensional (2D) structure or pattern desired for a sole, wherein said bi-dimensional (2D) structure or pattern comprises at least one lug for a sole or outsole of a footwear, for example shoe, a sport shoe or a work footwear or a boot, wherein said lug comprises a first base, a second base and a sidewall, wherein said first base is suitable to contact the ground during use, said second base is suitable to be attached to the sole or outsole and/or it is opposite to said first base and said sidewall is suitable to connect laterally said first base and said second base, wherein said lug comprises features and/or elements at least at a part of said sidewall able to confer to said lug traction and grip on grounds or terrains consisting of granular particulates or penetrable surfaces, wherein said features and/or elements comprise at least one protrusion and/or at least one indentation, wherein said at least one protrusion has a prismatic shape and is constituted by faces, each face or at least one face thereof having a rectangular shape, a square shape, or a trapezoidal shape,   optionally indicate in said bi-dimensional (2D) structure or pattern the position and shape of at least one logo and/or trademark,   determine a three-dimensional (3D) digital file corresponding to said bi-dimensional (2D) structure or pattern,   print at least one model by a 3D printing machine, solidifying said model in a shape substantially corresponding to a structure complementary to said mold,   cast pouring a molten metal,   solidify the molten metal, in order to obtain said mold,   after the step of printing, clean parts, not interested by the final shape of the solidified model,   after the step of casting and solidifying, remove parts of the solidified model from the solidified mold.   
     
     
         22 . The method for obtaining a sole of a footwear, for example an outsole of a shoe, a sport shoes or a work footwear or a boot, wherein said sole comprises an upper surface, adapted in use to face toward the foot of a user, and a lower surface, adapted in use to face toward the resting surface or the ground, wherein said lower surface comprises at least one and/or a plurality of lugs wherein said lug comprises a first base, a second base and a sidewall, wherein said first base is suitable to contact the ground during use, said second base is suitable to be attached to the sole or outsole and/or it is opposite to said first base and said sidewall is suitable to connect laterally said first base and said second base, wherein said lug comprises features and/or elements at least at a part of said sidewall able to confer to said lug traction and grip on grounds or terrains consisting of granular particulates or penetrable surfaces, wherein said features and/or elements comprise at least one protrusion and/or at least one indentation, wherein said at least one protrusion has a prismatic shape and is constituted by faces, each face or at least one face thereof having a rectangular shape, a square shape, or a trapezoidal shape, comprising the following steps:
 provide a mold according to claim  21 ,   pour in said mold a material for said sole,   solidify said material for said sole and obtain said sole equipped with at least one lug and/or a plurality of lugs.