| 摘要 |
PURPOSE:To perform energy saving operation in the total range of a rated air quantity, by performing fixed wind pressure control to a fixed air quantity range in a surge region and on-off control in an air quantity below the fixed air quantity range. CONSTITUTION:In an air quantity range of surge region, switches 18 and 19 are operated by a sequence circuit 17 to hold the opening of a suction valve 3 to a prescribed opening, while to hold pressure of a delivery side conduction pipe 8a to a fixed condition, fixed wind pressure control, in which opening and closing of an air relief valve 7 are continuously controlled, is performed by a pressure indication adjusting meter 20, further when an air quantity becomes below Qo, normal on-off control is performed. In this way, an energy saving effect is obtained. |
