| 摘要 |
In each protrusion-forming recess (42) of a mold, a non-through-hole vent (44) is provided at one end side, and a through-hole vent (46) that is longer than the non-through-hole vent (44) is provided at another end side. When there is an ingress of rubber of a green tire into each protrusion-forming recess (42), air inside the protrusion-forming recess (42) is discharged through the through-hole vent (46) and the minute amount of air remaining inside escapes to the non-through-hole vent (44). Each through-hole vent (46) is set with a large capacity, enabling an ingress of rubber into the vent hole that will later become spew to be stopped inside the through-hole vent (46). Since the volume of air that is trapped inside the protrusion-forming recess (42) is a minute amount, the volume of air that escapes into the non-through-hole vent (44) is also a minute amount. This enables a phenomenon, in which the portion of rubber in contact with air inside the non-through-hole vent (44) becomes sticky after vulcanization, to be suppressed. |
