| 摘要 |
PURPOSE:To improve driving force by obtaining sufficient tire tread pressure on uneven ground, by alternatively forming portions with high rigidity and portions with low rigidity, which indentation quantities in the tire inner diameter direction differ when a tire contacts the earth, in the tire circumferential direction. CONSTITUTION:This tire 20 for uneven ground is provided with a tread pattern shown in the development drawing, and produced by symmetrically disposing a number of projections onto a center line N-N of the tire in a tread portion 20a of the tire 20. The tread portion 20a is equipped with a central projection portion 21 arranged onto the center line N-N, four block-like projection portions 22 - 25 disposed to each vertex of a quadrilateral (a) surrounding the projection portion 21 and projection portions 26, 27 arranged to the outsides of outside projection portions 22 - 25 on a line (b) passing through the central projection portion 21, and formed from portions A, in which the rigidity of the tread portion 20a is made lower than the mean of the whole tire, and portions B, which are provided with lateral long projection portions 28 and projection portions 29 - 32 and which rigidity is made higher. |
