Patent ID: 8230771

Claim:
Hydraulic arrangement for regulating a lifting mechanism ( 12 ) of an agricultural machine ( 10 ), with at least one first hydraulic cylinder ( 24 ) having a chamber ( 50 ) capable of being acted upon by pressure, with at least one proportionally adjustable inflow valve ( 22 ) which is connected on the outlet side via a first inflow line ( 30 ) to the chamber ( 50 ) and which is connected on the inlet side to a hydraulic pump ( 18 , 18 ′), with at least one first outflow line ( 32 ) which makes a connection between the chamber ( 50 ) and a hydraulic tank ( 20 ), with adjustment means ( 42 , 44 ) for generating an adjustment signal for the hydraulic cylinder ( 24 ), and with an electronic control unit ( 40 ), characterized in that a first electroproportional pressure relief valve ( 26 ) is arranged in the first outflow line ( 32 ) and a first non-return valve ( 28 ) closing in the direction of the inflow valve ( 22 ) is arranged in the first inflow line ( 30 ), and also one or more sensors ( 36 , 38 ) related to the at least first hydraulic cylinder ( 24 ) and generating a sensor signal are provided, the at least first pressure relief valve ( 26 ) being controllable or regulatable as a function of the one or more sensor signals and/or of the adjustment signal.