| 摘要 |
The present invention relates to a pump system comprising a pump (10) having a generally cylindrical pump housing (12); which pump housing (12) is arranged with a liquid inlet (14) in one end and a liquid outlet (16) in a second end; a tubular membrane (18) arranged inside said pump housing (12); a first passage (22) arranged in the vicinity of said liquid inlet (14) for introducing pressurized fluid between said membrane (18) and said housing (12); a second passage (24) arranged in the vicinity of said liquid outlet (16) for releasing said pressurized fluid; in that the membrane (18) is arranged with an elasticity providing a local radial compression and an annular fluid compartment (50) when a pulse of pressurized fluid is entered through the first passage (22); wherein said annular fluid compartment (50) travels along said housing (12), bringing a volume of liquid with it. The invention is characterised in that the system further comprises an expansion vessel (46) operably attached to said liquid outlet (16) for reducing pressure changes in said liquid caused by the action of said pulse of pressurized fluid. |
