| 摘要 |
<p>1,241,790. Pneumatic tyres. MICHELIN & CIE (Compagnie Generale des Etabs Michelin). 18 June, 1970 [19 June, 1969], No. 29711/70. Heading B7C. A tread 1 of a radial carcass pneumatic tyre has circumferential zigzag ribs 3, Fig. 1, which may be continuous or discontinuous and which are bounded by grooves 2, the side walls 12, 13 of the ribs being inclined to the normal to the surface of the tread, intersecting the junction of surface and side wall, at an angleαwhich varies progressively over the length of one complete zigzag from a minimum at each point 10 of the zigzag which projects into the neighbouring groove, to a maximum at re-entrant angles 11 of the zigzag. The minimum angleαof inclination of the walls 12, 13 is - 10 degrees, i.e. the wall is undercut, and the maximum angle of inclination is 30 degrees. At a point mid-way between a change of direction of the limbs of the zigzag, the walls 12, 13 have equal and opposite inclinations #, Fig. 3, to the surface of the tread 1.</p> |
