ROTOR BLADE CONTROLLING DEVICE FOR ROTOR BLADE CONTROL TYPE AXIALLFLOW FAN

摘要

PURPOSE:To provide the rotor blade controlling system for the rotor blade control type axial-flow fan, which is provided with a dead time generating means in its hydraulic circuit for operating the rotor blades, so that it may not respond to short-period fluctuation of air amount but it is operated to move the blades in case that fluctuation in the air amount, having periods longer than a predetermined time length, is caused in controlling the amount of air to be supplied to a thermal power plant or the like. CONSTITUTION:An actually measured air amount (q) at the time is compared with an instructed air amount Q in a controller 17 and the output signal of the controller 17 is given to an actuator 13. Here, if fluctuation is caused in the actually measured air amount (q) and resultantly an arm of actuator 13 is moved vertically at short periods although the average air amount indicates correctly the instructed air amount Q, it only causes lateral movement of a piston 22 of a dead time generating means 20. Therefore, it is prevented that hydraulic pressure is acted to a control cylinder 6.