PNEUMATIC TIRE Russian patent published in 2013 - IPC B60C11/12 

FIELD: transport.

SUBSTANCE: invention relates to tread of tires to be used in winter. Pneumatic tire comprises splines 2 with ledges 2 on first of its two opposed walls and aligned therewith along contour of recess 3 on second wall of said spline. Besides, projection of wall spline with ledges 2 in open state features relationship between density of location of X ledges in area extending to half the depth of alpine H from open side of spline 1, and density of location of ledges Y in area extending to half the depth of alpine H from base of spline 1 is given by X>Y.

EFFECT: better braking on ice.

4 cl, 7 dwg, 2 tbl