Lift Up Operation - Toyota 7FBEF 15 Service Manual

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5. Lift UP operation

When the lift lever is pushed to the UP side, solenoid b1 is energized and the solenoid proportional
valve moves to the right. Then the pressure oil controlled by the pressure reducing valve flows to
chamber (k) on the left side, and the lift spool moves to the right side.
The volume of oil that flows to chamber (k) is proportional to the distance the lever is operated.
Pressure oil flowing from chamber (a) in the inlet section pushes down the load check, then flows
through part L and chamber 7 to move the lift lock check valve, and then flows to the port C1 and the
bottom of the lift cylinder.
The select valve does not operate at this time, so the select valve becomes simply a check valve.
The pressure differential between chamber (a) and chamber 7 is kept constant by the pressure
compensation mechanism and the load sensing mechanism, so the volume of pressure oil supplied to
port C1 is determined by the opening aperture of part L irrespective of the load.
Lift UP operation (lift section)
Inlet section
Tilt section
Lift spool
(k)
Solenoid b1
Electromagnetic proportional valve
Load check
(a)
Section S-S
L
S S
7 8
Lift logic valve
Port C1
Electromagnetic proportional valve
10
Main flow/excess flow
Pilot flow
Logic selection valve
Spring 5
Solenoid a1