| 摘要 |
The equipment comprises a back valve (11) in water supply (15) between water pump (6) and hydrophore, in addition to pressure-sensitive electrical switch (8) for pump. A water-filled aeration vessel (16) is between pump and back valve with inlet (25) for water from pump, outlet (26) to hydrophore via back valve and drain (21) with automatic valve (23) opened to remove water when vessel pressure falls below set underpressure and vacuum valve (20) opened at lower pressure to let in air. |
