| 摘要 |
A double diaphragm pump comprises a pair of chambers (14, 15), each with a plate and diaphragm arrangement (23, 24 and 25, 26) which forms parts of the boundaries thereof. A pressurised fluid such as air is directed alternately to respective spaces (31, 32) outside the chambers and adjacent the diaphragms by means of an actuating means (30) which comprises a spool (34) in a spool chamber (33). A control means (9) which comprises a rod (27) extending between the plates (23 and 25) controls operation of the actuating means. The control means which is movable with the diaphragms directs fluid alternately to the ends of the spool chamber and prevents supply of fluid to an end of the spool chamber opposite to that end to which fluid is directed at a selected moment. |
