A center mechanism of a tire vulcanizer is provided with a screwing mechanism provided with a screw shaft and a screw nut screwed onto the screw shaft, a motor for rotating the screw shaft so as to raise and lower an upper ring body, an inverter for controlling the motor, and a mechanical brake for retaining a predetermined position of the upper ring body so that a bladder retains a shaping state. Within a time range from start of a closing action of the upper die to contact between the upper die and the upper ring body, an operation of the mechanical brake is released and position control of the upper ring body by the inverter is started, and at least after the release of the operation of the mechanical brake, a position of the upper ring body is controlled by the inverter. By such a configuration, even when there is an erroneous operation of the brake or incorrect setting, it is possible to prevent damage and breakage of constituent parts and have a simple structure.