TYM T303HST, Workshop Manual

Page: 184 / 249

-When the solenoid is switched
「
「 「
「
ON
」
」 」
」
The fluid from the pump flows to port B through port P,the pressure-reducing valve,and the
changeover valve.
The pressure of the PTO clutch circuit and that of passage(2) are the same and will be set as P ₂ .The
pressurized fluid acts on the left-hand side of the valve,passing through port ; its pressure will be set as
P
₁ .
As passage (1) and passage (2) are interconnected,then P ₁ =P ₂ .
The force imposed upon the left-hand side of the valve is P1 whereas the force imposed upon the right
side of the valve is P1 plus the spring force.Consequently the spool is pushed leftwards.
Here port A is blocked, so the fluid from the pump is branched off to the PTO clutch.
(1)Passage 1
(2)passage 2
(3)Pressure-reducing valve
(4)Changeover valve
(5)PTO clutch
(6)To control valve.
9-5
Fig.9-4