| 摘要 |
PURPOSE: To suppress rubber biting on the separation surface at the time of closing vulcanizing mold so as to prevent generation of flash by providing a recess of a specific size having gaps in the circumferential direction on the reference surface extending from a tread end facing outward in the radial direction of separation surface equivalent line to a side wall part and a peripheral directional groove. CONSTITUTION: A recessed part 12 positioned outward in the radial direction of separation surface equivalent line 9 and extending outward in the radial direction by starting from the separation surface equivalent line 9 and whose depth D1 from the reference surface 10 smoothly extending from a tread end E to a side wall part 3, is from 0.5 to 5.0mm and whose maximum length at the position of the peripheral directional maximum width is from 5.0 to 10.5mm is provided on the outer surface of a tire. The recessed part 12 has gaps 11 in its peripheral direction at constant pitches. Furthermore, a peripheral directional groove 13 having depth D2 from the reference surface 10 is from 1.0 to 3.0mm and having radial directional width W from 2 to 10mm is formed on the radial directional inside of the separate surface equivalent line 9. Accordingly, the projection of mold for forming the recessed part 12 and the projection streak part of the mold for forming the peripheral directional groove 13 depress the vicinity of a buttless when the molds are closed so as to separate the buttless part so that rubber biting may be suppressed. |
