NON-STUDDED TIRE Russian patent published in 2012 - IPC B60C11/04 B60C11/11 B60C11/12 

FIELD: automobile industry.

SUBSTANCE: this invention covers tread design of an automobile tyre including tread 2. Tread design has a pair of middle annular grooves 3b each of which is located at the distance of 15-20% tread width (TW) from center line (С) of the tread to ensure crown area (CR) between middle grooves 3b and a pair of shoulder areas (Sh) between middle groove 3b and limit (E) of ground contact where (CR) includes rows R1 and R2 of bulges (B) with slots (S) and limited by meander inner annual grooves 3a and lateral grooves 4a and 4b of (CR). Each shoulder area (Sh) includes rows R3 and R4 of bulges (B) with slots (S) and limited by linear outer annual grooves 3c and lateral grooves 4c and 4d of Sh. Gs portion (%) of the grooves area in shoulder (Sh) exceeds Gc portion (%) of the grooves area of crown area (CR), so that Gs-Gc differential is equal to 3-7%.

EFFECT: improvement of tire quality at icy and snow road surfaces.

6 cl, 7 dwg