DIAPHRAGM PUMP AND METHOD TO CONTROL FLUID PRESSURE THEREIN Russian patent published in 2010 - IPC F04B43/67 

FIELD: engines and pumps.

SUBSTANCE: hydraulic drive pump comprises diaphragm, piston, transfer chamber, fluid chamber and spool-valve element. Transfer chamber is arranged between diaphragm and piston and filled with operating fluid. Fluid chamber communicates with transfer chamber via at least one valve. Spool-valve element allows controlling fluid flow between transfer chamber and fluid chamber. Spool-valve element serves to open and close bore in one valve in case transfer chamber is overfilled or filled insufficiently.

EFFECT: possibility to use flexible small-size rubber diaphragms that sustain high elastic strains.

17 cl, 7 dwg