4-8
As the spool is pushed to the right side, the EF line circuit opens, allowing almost all the pump discharge to
flow from the EF line to the control valve.
When steering operation is performed
Turning the steering wheel opens the control orifice in the steering valve and opens the CF line.
The lower side pressure of the control orifice goes through the LS pilot line to the RH chamber, generating
the pressure difference with the LH chamber in which the pressure is equal to that of the upper control
orifice. The pressure difference differs depending on the opening of the control orifice (steering speed).
The spool is operated by this pressure difference to divide some pressure from the pump and supply
adequate hydraulic oil to the steering valve.