| 摘要 |
PURPOSE:To enable to convey fluid with small change of discharge pressure, by controlling the effective width of pump or fan blades automatically according to the change in the demand for fluid at the place where fluid is to be conveyed. CONSTITUTION:With reduction of demand for fluid to be conveyed, the discharge pressure of a pump is increased. By transmitting this discharge pressure into a first pressure chamber 11 via a pressure outlet port 1d, adjustment valve 10, conduit 9, pressure inlet port 1c, second pressure chamber 8 and through-hole 2e, a force urging a partition plate 3 toward the suction opening 1a is produced in the first pressure chamber 11 since pressure at the suction opening 1a is relatively low, so that the partition plate 3 is moved toward the suction opening 1a and the effective width of blades 2a is decreased resultantly. Here, if the adjustment valve 10 is controlled to obtain a proper effect width of the blades 2a, fluid can be conveyed with less change in the discharge pressure of pump. |
