| 摘要 |
PURPOSE:To improve braking and turning performances by inclining the small grooves of a tire toward the forward side of a rotational direction from the deepest part to the open part thereof, and furthermore inclining the extension direction of the grooves toward an equator surface in a tire having small grooves separated from each other in a peripheral direction on a tread part. CONSTITUTION:A plurality of small grooves 11 are extended approximately in an axial direction at an equal pitch on the periphery of a tread part 3. And the small grooves 11 are so inclined as to be directed toward the forward side of a tire rotational direction 'Q' in the course of extension from the deepest part 10a to the open end 10b thereof. In this case, a crossing angle 'J' is set to about 5 deg.-30 deg. at the intersection of the small grooves 11 with a vertical line 'D' to the surface of the tread part 5 in a cross section in parallel with an equator surface 2. Also, the small grooves 11 are inclined toward the equator surface 2 at an angle 'K' so as to be directed to the rear side of the tire rotational direction 'Q', all the more in the vicinity of said surface 2. The inclination 'K' is set to about 50 deg.-80 deg.. According to the aforesaid constitution, braking and turning performances can be improved. |
