Mow Circuit - Toro Reelmaster 7000 Service Manual

Mow Circuit

Hydraulic flow for the mow circuit is supplied by two (2)
sections of the gear pump (P1 and P2). Gear pump sec-
tion P1 supplies hydraulic flow to cutting units 1, 4 and
5 (front cutting units), while gear pump section P2
supplies cutting units 2 and 3 (rear cutting units).
A single mow control manifold is used to control flow
from the two (2) pump sections. The manifold includes
cartridge valves for control of each of the two (2) pump
circuits. Each manifold circuit is equipped with a sole-
noid controlled, proportional valve (SP1 and SP2), a log-
ic cartridge (LC1 and LC2) and a circuit relief cartridge
(RV1 and RV2).
All cutting reel motors are equipped with cross over relief
valves to prevent hydraulic component damage in case
a cutting reel should stall.
The TEC controller uses inputs from various machine
switches to determine when solenoid proportional valve
(SP1 and SP2) are to be energized. The controller also
provides a slight delay in activation of the rear cutting
units.
NOTE: When the mow speed limiter is in the transport
(2WD) position, the mow circuit cannot be engaged.
PTO Disengaged (Fig. 15)
When the PTO switch is OFF (or if the cutting units are
raised), the manifold proportional valves (SP1 and SP2)
are not energized, which causes a pressure increase
that shifts the logic cartridges (LC1 and LC2). The pump
flow is routed through the shifted logic cartridge and out
manifold port T1. Return oil from the manifold is directed
to the oil cooler and oil filter.
PTO Engaged
When the PTO switch is turned ON with the cutting units
lowered, the manifold proportional valves (SP1 and
SP2) are energized with outputs from the TEC--5002
controller. The energized valves shift to direct pump flow
toward the cutting unit motors. Flow from the valves is
proportional to current applied to the valve coil by the
TEC controller. The setting of the reel speed control pro-
vides the input for the TEC controller to allow the ap-
propriate current to the valve coil.
Flow through the speed control valve is pressure com-
pensated by the logic cartridge valves (LC1 and LC2).
The logic cartridge valve maintains a pressure of 110
PSI (7.6 bar) across the proportional valve. Any excess
flow is returned to the hydraulic reservoir.
Maximum mow circuit pressure is limited at each mow
manifold circuit by the relief valve (RV1 or RV2). The re-
lief valve pressure is 3000 PSI (207 bar).
Reelmaster 7000
When the reels are shut off, the over--running inertia
load of the reels keeps driving the reel motors and can
turn them into pumps. The check valves (CV1 and CV2)
in the mow control manifold will open to keep the reel
motor circuit full of oil so the motors will not cavitate.
Backlap
When either of the mow control manifold backlap valves
are rotated to the backlap (R) position, pump flow to the
cutting unit motors is reversed. This change in flow di-
rection reverses the rotation of the front or rear cutting
reel motors allowing the backlap operation.
#4
CUTTING UNIT LOCATIONS
M4 M1
FROM GEAR
PUMP P1
Page 4 - - 21
#1 #5
#2 #3
Figure 14
M5
M2
M1 M2 M4 M3
MV2
MV1
CV2
OR1 CV1 OR2
LC1 LC2
SP1 SP2
RV1 RV2
P1 T2 T1 P2
FROM GEAR
PUMP P2
Figure 15
Hydraulic System
M3
MOW
CONTROL
MANIFOLD