| 摘要 |
<p>PROBLEM TO BE SOLVED: To stably perform an angular displacement drive for rotor blades in controlling the air capacity of an axial-flow air-blower for the ventilation of a road tunnel with high accuracy by means of a pneumatic cylinder. SOLUTION: A target displacement signal Qi for the blade angle of each rotor blade is generated in the period of a first time W1, for example, while being renewed at every 30 minutes, so as to be stored and held in a memory 6, the displacement Qf of each rotor blade is detected by a detection means 86, the difference eq (=MQi-Qf) between a displacement command signal MQi stored in the memory and the detected displacement Qf is obtained by a subtractor 8, a blade angle control signal Q(n) (=Q(n-1)+eq) for letting the displacement Qf of each rotor blade be turned out to be a displacement representing the displacement command signal Q (n-1) (=Qi), is thereby formed, so that a pneumatic cylinder 3 is thereby driven. The aforesaid difference eq is repeatedly obtained by the subtractor 8 while being repeated several times within the period of a first time W1, and for example, every 30 minutes within the period of a second time W2, so that the blade angle control signal Q(n) is thereby corrected so as to be started over again.</p> |
