VENT PIECE, TIRE VULCANIZATION MOLD WITH VENT PIECE, AND TIRE MANUFACTURED USING TIRE VULCANIZATION MOLD

摘要

[Subject Matter] To provide a vent piece capable of maintaining normal opening/closing functions of a vent channel by securing the smooth movement of a plug so that defects in the external appearance of the finished tire are reduced.;[Solution(s)] A vent piece 1 to be installed in a vent channel 110 of a tire vulcanization mold 100 has a cylindrical tube 2 installed at one end (110a) of the vent channel 110 and having a through hole 21 extending in an axial direction, and a plug 5 loaded in the through hole 21 to be movable in an axial direction. The cylindrical tube 2 has a first bearing surface 22. The plug 5 has a second bearing surface 53 facing the first bearing surface 22, and is movable between a closed position where the second bearing surface 53 makes contact with the first bearing surface 22 to close the vent channel and an open position where the second bearing surface 53 is separated from the first bearing surface 22 to open the vent channel. A film 25 or film 54 to reduce friction is formed on at least part of at least the first bearing surface 22 or the second bearing surface 53.