| 摘要 |
The invention concerns a suction device (10) for sucking liquid out of a ventilated sewage-storage tank by means of an underpressure produced by the suction device linked to the sewage tank. The device comprises a remotely or hand-operated control valve (40), a first shut-off valve (30), such as a diaphragm valve, which is connected to the control valve and cuts in and out the underpressure required for the suction process, plus optionally a second shut-off valve disposed between the tank and the suction device and actuated by the underpressure. In order to be able to suck sewage out of the tank, irrespective of whether a second shut-off valve is fitted between the tank and the suction device, the suction device (10) has sensor elements (18, 24) which permit the presence or absence of the second shut-off valve to be determined and which permit the first shut-off valve to be controlled, directly or indirectly, by the control valve. |
