wsm M7060 Workshop Manual page 358

M6060, M7060, WSM
Partial Braking of Trailer Brake
The trailer braking pressure Pb (acting on surface (1)
of control spool (2)) is in equilibrium with the tractor
braking pressure Px (acting on piston (7)).
The brake line B remains separated from the
reservoir and the oil in the trailer brake is thus enclosed.
Control spool (2) is shifted to the right after the
pressures have equalized and opens bore (8) to the
reservoir through port R. Control spool (2) is in position
d. Flow control valve (10) is thus switched into position a
and has no regulating function.
As in the case of the released trailer brake, the
delivery flow Qp from the pump passes through port N
and flows as Qp - Qx to the tractor hydraulic system. A
control flow Qx passes to the reservoir through control
spool (2).
(1) Piston Surface
(2) Control Spool
(3) Pressure Relief Element
(4) Spring
(5) Bleed Valve
(6) Control Head
(7) Piston
(8) Bore
(9) Throttle
(10) Flow Control Valve
(11) Restrictor
(12) Bore
(13) Check Valve
4-M7
BRAKES
P: Port for 3P Hydraulic Pump
N: Port for 3P Control Valve
B: Port for Trailer Brake
R: Port for Reservoir
(Transmission Case)
X: Port for Tractor Service
Brake
Qp: Delivery Flow
Qx: Control Flow
9Y1210828BRM0007US0
KiSC issued 08, 2013 A