| 摘要 |
<p>A vacuum type sewage collecting system for collecting sewage from a plurality of houses or the like facilities which stores sewage in a sewage reservoir and then delivers the sewage stored in the sewage reservoir to a sewage treatment station or a like installation through a vacuum valve and a vacuum sewage pipe wherein opening/closing operations of the vacuum valve are properly controlled by a vacuum valve controller. The controller includes a first vacuum chamber connected to the vacuum sewage pipe via a fluid flow resisting device, a second vacuum chamber likewise connected to the vacuum sewage pipe, an atmospheric pressure introducing unit for introducing an atmospheric pressure into the first vacuum chamber when it is determined on the basis of a result derived from detection of a quantity of sewage stored in the sewage reservoir that the detected quantity exceeds a predetermined value, and a shifting unit for shifting a negative pressure to be fed to the vacuum valve to open or close the latter depending on the present differential pressure between the first vacuum chamber and the second vacuum chamber. A first opening/closing valve is disposed in a parallel relationship relative to the fluid flow resisting device such that the first opening/closing valve is closed when the negative pressure in the vacuum sewage pipe is lower than a preset value. A closed type air tank is connected to the first vacuum chamber via a second opening/closing valve such that the second opening/closing valve is opened when the negative pressure in the vacuum sewage pipe is lower than the preset value.</p> |
