To enable pressure detecting sensors to be protected even if the load level of a pressure to be detected is high.
A pressure detecting device is constituted of a first cylinder part S1 with one end connected to a first pressure passage part 8 of pressurized air and the other end as a bottom surface, a first action valve 1a arranged in such a way as to be slidable by the pressurized air in the cylinder part S1, a first pressure sensor to detect the pressure of a first pressure measuring space Z1 formed of the first action valve 1a and the first cylinder part S1, a second pressure passage part A1 to guide a part of the pressurized air to the outside of the first cylinder part S1 at the time when the first action valve 1a is slid by the pressurized air by a predetermined amount or more, a second cylinder part S2 connected to the second pressure passage part A1, a second action valve 1b arranged in such a way as to be slidable by the pressurized air in the second cylinder part S2, a second pressure sensor 3b to detect the pressure of a second pressure measuring space Z2 formed of the second action valve 1b and the second cylinder part S2, and first and second air pressure reducing means to discharge a part of the pressurized air to the outside of both cylinder parts S1 and S2 at the time when the first and second action valves 1a and 1b are each slid in the first and second cylinder parts S1 and S2 by the pressurized air a predetermined amount or more.
SAITO YOSHINOBU
SUZUKI MINORU
Next Patent: DEVICE AND METHOD FOR PRESSURE DETECTION