-When the solenoid is switched 「
「「
「ON」
」」
」
The fluid from the steering valve flows to port P2 through oil cooler and the pressure-reducing valve
The pressure of the PTO clutch circuit are the same and will be set as relief valve in the hydrostatic
unit. The pressurized fluid acts on the left-hand side of the valve, passing through port ; its pressure
will be set as P2.
As PTO valve and HST unit are interconnected, then P2=HST unit.
The force imposed upon the left-hand side of the valve is P2 whereas the force imposed upon the right
side of the valve is T2 plus the spring force. Consequently the spool is pushed rightwards.
Here port A is blocked, so the fluid from the steering valve is branched off to the PTO clutch.
9-5
Fig. 9-4 PTO solenoid switch 「
「「
「ON」position