
2-50
COUNTERBALANCE VALVE
Control valve
Spring L(37)
Orifice L(40)
P1
P2
Spring R(37)
Orifice R(40)
Spring L(31-3)
Check valve L(31-2)
Plunger(31-1)
Spring R(31-3)
Check valve R(31-2)
Plunger notch portion
Motor
M1
M2
2)
R35Z72TM04
The counterbalance valve is provided to stop the axial piston motor and to prevent overrun. When
the control valve is set to the neutral position, there is no pressure in the ports P1 and P2, and ports
M1 and M2 are blocked by plunger (31-1) and check valve (31-2), consequently the motor does not
start rotating.