AIR PRESSURE CONTROLLING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an air pressure control device for effectively preventing generation of overshoot and undershoot attributable to the differential pressure between the target pressure and the original pressure of a compressed air source or the atmospheric pressure, effectively preventing generation of overshoot and undershoot even when the air pressure in a brake cylinder is largely changed, and rapidly giving a desired braking force in a stable condition. SOLUTION: When performing forcible lapping to forcibly switching a three-position solenoid valve 12 at a slow supply position or a slow exhaust position to an overlap position according to the result of comparison of the target command pressure value PBCOwith the detected pressure value PBCfrom a pressure sensor 13, a control unit 15 increases the value of the reference overlap change to start the forcible overlapping as the target pressure value PBCOis increased when the solenoid valve 12 is at a low supply position, and increases the reference overlap change as the target pressure value PBCOis decreased when the solenoid valve 12 is at a slow exhaust position. COPYRIGHT: (C)2004,JPO