TIC Liner 3000 with Communicator Individual functions Description of function: No volume flow is flowing The pressure spring pushes the control piston of the input pressure balance (763) to its stop. The connection from P to T is closed. Volume flow is flowing – no solenoid valve is actuated Volume flow is supplied via channel P and flows to each of the downstream control units. Since no solenoid valve has been actuated, each spool blocks the volume flow. This builds up pressure which acts on the left-hand end of the input pressure balance (763) control piston and pushes it against the pressure spring. This opens the connection from P to T.
At the same time, a partial volume flow flows via the orifice plate (in the control piston) into the spring space of the control piston. The spring space is not pressurized since it is connected to the channel (LS). A fixed pressure difference is established at the control piston. One solenoid valve is actuated When a downstream solenoid valve is actuated, volume flow flows via channel P and the spool into the cylinder(s). The load pressure built up now is directed into the spring space of the input pressure balance (763) control piston via the LS channel. The pressure build-up controls the control piston so that the connection from P to T is partly closed.
This closing is necessary to make volume flow available for actuating the cylinder(s). However, the control piston is displaced to the left only until the fixed pressure difference is re-established. A partial volume flow will continue to flow into the tank. When the cylinders are at their stop position, the pressure rises and is available in the spring space of the input pressure balance (763) control piston via the LS channel and presses the control piston to its stop. The pressure in channel P opens the pressure control valve (706). 12/03 Lin-h-Kap2 2-3