Toro Reelmaster 7000 Service Manual page 51

Lower Cutting Units
A four section gear pump is coupled to the piston (trac-
tion) pump. Gear pump section P3 supplies hydraulic
flow to both the lift control manifold and the steering con-
trol valve. Hydraulic flow from this pump section is deliv-
ered to the circuits through a proportional flow divider
located in the fan control manifold. Maximum lift/lower
circuit pressure is limited to 1700 PSI (117 bar) by a relief
valve (RV1) in the lift control manifold. Lift circuit pres-
sure can be monitored at the test fitting in lift control
manifold port G.
A single lift switch on the console arm is used to raise
and lower the five (5) cutting units (Fig. 10). The lift
switch acts as an input to the TEC controller to send
electrical outputs to appropriate lift control manifold so-
lenoid coils in order to raise or lower the cutting units.
When the cutting units are in a stationary position (not
raising or lowering), lift circuit flow from gear pump sec-
tion P3 bypasses the lift cylinders through the lift control
manifold solenoid valve S1 (de--energized). Return flow
from the manifold is routed to the oil filter and traction
charge circuit.
Cutting Unit Lower
NOTE: The operator must be in the operator seat in or-
der to lower the cutting units. Also, when in transport
speed (2WD), the cutting units will not lower.
When the lift switch is pressed to the lower position, so-
lenoid valve S1 along with solenoid valves S3, S4 and
S5 are energized by the TEC controller. To allow the
front cutting units to be lowered before the rear cutting
units, the controller slightly delays energizing solenoid
S5 after the lift switch is pressed. The energized sole-
noid valves direct gear pump oil flow to the barrel end of
the lift cylinders. Flow control orifices in the lift control
manifold (C2 and C4) are bypassed when lowering the
cutting units.
Hydraulic pressure causes the lift cylinder shafts to ex-
tend, and lower the cutting units. The three (3) piloted
check valves in the junction manifold are shifted by hy-
draulic pressure to allow return flow from the extending
lift cylinders for the front cutting units. Flow control orifi-
ces in the junction manifold control the front cutting unit
lowering speed by providing a restriction for the return
flow from the front lift cylinders. Rear cutting unit lower-
ing speed is controlled by a flow control orifice in the lift
control manifold (port C3).
Reelmaster 7000
Because cutting unit weight assists in extending the lift
cylinders when lowering the cutting units, less hydraulic
pressure is necessary during the cutting unit lowering
operation. Lift circuit lower relief valve (RV2) allows lift
circuit pressure to be limited to 500 PSI (34 bar) while
lowering the cutting units.
NOTE: Adjustment of lift circuit lower relief valve (RV2)
is not recommended.
When the lift switch is released, solenoid valves S1, S3,
S4 and S5 are de--energized and the lift cylinders and
cutting units are held in position.
1
1. Console
#4
CUTTING UNIT LOCATIONS
Page 4 - - 17
2
Figure 10
2. Lift switch
#1 #5
#2 #3
Figure 11
Hydraulic System