| 摘要 |
PROBLEM TO BE SOLVED: To improve an adjusting performance for adjusting a ventilation quantity or internal pressure. SOLUTION: Fan control means 9A, 10A, 9B and 10B are provided for adjusting the outputs of fans Fs and Fr connected to main air ducts 2 and 3 go that all the opening degrees a1 to a3 and b1 to b3 of air quantity adjusting dampers Vs and Vr for adjusting a ventilation quantity or internal pressure in branch air ducts 2a and 3a are located within target intermediate opening degree ranges X and Y in which upper and lower limits are both set to an intermediate opening degree value. Target range correcting means 11A and 11B are provided for correcting the target intermediate opening degree ranges X and Y to a large opening degree side when the average values Ha and Hb of the detected opening degrees a1 to a3 and b1 to b3 of the air quantity adjusting dampers Vs and Vr are smaller than set target average values Has and Hbs and correcting the target intermediate opening degree ranges X and Y to a small opening degree side when the average values Ha and Hb of the detected opening degrees a1 to a3 and b1 to b3 are larger than the set target average values Has and Hbs. |
