| 摘要 |
A mold for vulcanization, wherein two blade holding gears (86) having an arc blade (90) and combined opposedly to each other are installed rotatably on the outer peripheral surfaces of a cope and a drag (14), racks (98) moved by cylinders are meshed with gears (88) formed on the outer peripheral side of the blade holding gears (86), a green tire is vulcanized with the tips of these two blades (90) in contact with each other on the inner side of a land part forming recessed part (22) and, after the vulcanization has been completed, the racks (98) are moved in the directions opposite to each other so as to extract the blade (90) from the land forming recessed part (22), whereby siping extending in arc shape which do not appear on the tread of a new tire but appear after it is worn are formed on the block of the tire. |
