To provide a pressure reducing valve for regulating tire air pressure which automatically evacuates the air when the air is excessively filled up, and can finish by closing the valve when the tire air pressure becomes the designated pressure.
A control part 22a of a transmitter 2 determines whether or not the tire air pressure Pa exceeds the predetermined designated pressure, and drives a motor 105 by controlling a switch 104 for driving a motor when the tire air pressure Pa exceeds the predetermined designated pressure. An intermediate shaft 107 in a valve core 106 is moved to open an air passage thereby, and it is possible to control so that the tire air pressure becomes the predetermined designated pressure. Therefore, the pressure reducing valve for regulating the tire air pressure can automatically evacuate the air when the air is excessively filled up, and finish by closing the valve when the tire air pressure becomes the designated pressure.
Takahiro Miura
Fumihiro Mizuno