Patent ID: 8517049
Filing Date: 2013-08-27
Classification: F15B,F16K,Y10T

Abstract:
1. A progressive hydraulic pressure relief valve (V, V′) for controlling pressure peaks in hydraulic motors and hydraulic circuits, which is mounted within a body ( 1 , 1 b ) of a hydraulic block for communication with a supply line (P, P′) and a discharge line (T, T′), said pressure relief valve (V, V′) comprising: a cartridge ( a spring-holding plug ( a closure member ( a main spring ( a piston ( a setting spring ( a spring plate ( a plate ( a chamber (C wherein said pressure relief valve (V) has coupling surfaces between: which are formed with geometric precision and sized to limit fluid leakage to less than 5 ml/min, at an operating pressure of the valve, said coupling surfaces being coaxial to ensure that friction during relative motion of the parts is negligible.