ELECTROHYDRAULIC BOREHOLE UNIT Russian patent published in 2014 - IPC F04B47/08 

FIELD: engines and pumps.

SUBSTANCE: proposed unit comprises motor articulated with working fluid driven pump, hydraulic control valve, diaphragm pump with cylindrical housing, suction and pressure valves and diaphragm. Said unit includes second diaphragm pump, device to initiate switchover of hydraulic control valve after termination of delivery and suction in at least one diaphragm pump in case mechanical load at diaphragm does no exceed permissible magnitude. Device for switchover of hydraulic control valve is composed of at least one valve fitted in the housing of at least one pump. This unit includes the device for maintaining constant oil volume in diaphragm pumps composed of compensator module comprising two areas divided by moving element, one being communicated with drill string-borehole annulue and at least one valve arranged in diaphragm housing.

EFFECT: higher reliability, longer life.

4 cl, 3 dwg