Device for controlling hydraulic device in applications that require long idle times and short operating times

摘要

A circulation valve (40) is disposed between the pump channel and the tank channel. The valve (40) both in the circulation mode position (80) of directional valve (24) and in the return mode position (82) of valve (24) relieves pressure via a relief line (38). This leads via directional valve (24) to reservoir (36), and in the forward function which is kept closed by a piston (50) acted upon by the pump pressure.Piston (50) is opened in the two above modes by throttle (6)) which causes a pressure drop across the piston when fluid is flowing through.