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

FIELD: transport.

SUBSTANCE: invention relates to configuration of grooves on wheel winter tire tread. Pneumatic tire comprises blind groove 5 on the surface of contact with road surface and at least: three grooves 4 extending radially from hidden axis 2 extending downward from aforesaid contact surface. Expanded section 6 whereat groove width is locally expanded at, at least, one position in mid section between hidden axis 2 and end section 4z of grooves 4.

EFFECT: better braking on ice.

17 cl, 12 dwg, 1 tbl