OVERFLOW VALVE OF DOWNHOLE MOTOR Russian patent published in 2010 - IPC E21B4/02 

FIELD: oil and gas industry.

SUBSTANCE: overflow valve includes housing and piston systems coaxial to each other, the first one of which includes branch pipe with the channels hydraulically connecting the cavity inside the housing to after-tube space, hydraulic cylinder barrel, valve lock, piston travel restrictors, and the second one includes hydraulic cylinder piston with central channel, switch of the valve with overflow channels to connect the central channel to annular cavity, compression spring with stop adjustment rings, which restricts the piston with the switch in upper position. Compression spring is located towards the flow below the overflow channels of the switch and lock of the valve.

EFFECT: increasing drilling properties.

3 cl, 3 dwg