Patent ID: 11906986
Assignee: PARKER HANNIFIN EMEA S.À.R.L.
Field: Mechanical elements (Mechanical engineering)
Classification: CPC F  G | IPC F  G

Claim 0:
1. A counter pressure valve arrangement for controlling a pressure level of a hydraulic fluid in a return line from a hydraulic actuator arrangement, the counter pressure valve arrangement comprising a counter pressure valve having:
a moveable valve member,
a counter pressure regulating port configured for being connected to the hydraulic actuator arrangement via the return line,
a tank port configured for being connected to a tank or low pressure reservoir for storing low pressure hydraulic fluid,
a pump port configured for being connected to a source of pressurised hydraulic fluid,
wherein a first position of the valve member effects fluid communication between the pump port and the counter pressure regulating port for supplying pressurised hydraulic fluid to the return line, and
wherein a second position of the valve member effects fluid communication between the counter pressure regulating port and the tank port for discharging hydraulic fluid from the return line to the tank, and
an electrohydraulic pilot valve that provides a variable pilot pressure acting on a first axial end of the valve member of the counter pressure valve,
wherein the electrohydraulic pilot valve has an input port configured to be fluidly connected to a pressure source, an output port configured to be connected to a pilot pressure port of the first axial end of the valve member of the counter pressure valve via a pilot pressure line, and a discharge port configured to be connected to the tank or the low pressure reservoir.