DIAPHRAGM PUMP OPERATING BY UNIFORMLY DISTRIBUTED LOAD

PROBLEM TO BE SOLVED: To facilitate an increase in capacity by making it possible to actuate uniformly distributed load on the substantially whole of a diaphragm by alternately actuating pressurized pressure and reduced pressure on the diaphragm via working fluid which is made to come into contact with the whole of a substantial one side surface of the diaphragm whose peripheral part is fixed to the inside of a pup main body. SOLUTION: When a crank 9 of a motor 13 is removed, a piston is operated in the vertical direction and positive/negative uniformly distributed load is repeatingly actuated on the whole of a substantial one side surface of a diaphragm 4 via working fluid 6 filled between a piston 5 and the diaphragm 4 within a cylinder 122. As a result, the diaphragm 4 deforms into upper and lower waveforms and efficiently and forcibly feeds comparatively large quantity of liquid sucked form an intake 2 from a discharge port 3. At this time, when air is used as working fluid 6, responsiveness is lowered and pulsation of forcibly fed fluid is suppressed. Because the substantially whole part of the diaphragm 4 except the peripheral part fixed to a pump main body 1 deforms, a capacity change can be set to a large degree and an increase in capacity is contrived.