Toro Reelmaster 5510 Series, Руководство по обслуживанию

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Mow Circuit (5610-D)
A 4-section gear pump is coupled to the piston (traction) pump. The gear pump
sections (P1) and (P2) supply hydraulic flow for the mow circuit. These gear
pumps take their suction from the hydraulic reservoir (
Figure 73 ).
The mow control manifold contains 2 independent control circuits for the front
and rear cutting units. Each circuit is supplied by its own pump section. The
pump section (P1) supplies hydraulic power to the rear cutting units through
mow control manifold port P1 and pump section (P2) supplies the front cutting
units through manifold port P2. Each mow circuit includes a solenoid controlled
proportional valve (SP1) and (SP2), a logic cartridge (LC1) and (LC2), a circuit
relief cartridge (RV1) and (RV2), and a manually controlled direction valve (MV1)
and (MV2). Both the circuits share manifold port T, which drains to the oil cooler,
oil filter, and hydraulic reservoir.
The cutting reel motors are equipped with a cross-over relief valve to prevent
hydraulic component damage in case a single cutting reel stalls.
The machine TEC uses inputs from various inputs to determine when the
solenoid proportional valves (SP1) and (SP2) are to be energized. The TEC also
provides a slight delay in activation of front and rear cutting units.
Reels Engaged
When the reel engage switch is turned O
N
and the cutting units are lowered, the
proportional valves (SP1) and (SP2) are energized by the TEC. The energized
valves shift to direct pump flow toward the cutting unit motors. The amount of
flow from the valves is proportional to the current applied to the valve coil by the
TEC. The reel speed (defined by the InfoCenter reel speed setting) provides the
input for the TEC to output the appropriate amount of current to the proportional
valve coils.
Flow through the proportional valves (SP1) and (SP2) is pressure compensated
by the logic cartridge valves (LC1) and (LC2). The logic cartridge valve maintains
a pressure of 758 kPa (110 psi) across the proportional valve. Any excess flow is
returned to the oil cooler, return filter, and hydraulic reservoir.
The maximum mow circuit pressure is limited by relief valve (RV1) and (RV2).
The rear cutting unit circuit is protected by relief valve (RV1) which is set at
17,237 kPa (2,500 psi). The front cutting unit circuit is protected by relief valve
(RV2) which is set at 24,132 kPa (3,500 psi).
Mow circuit pressure for the rear cutting units (pump section P1) can be
measured at the manifold port G1, and mow circuit pressure for the front cutting
units (pump section P2) can be measured at manifold port G2.
Reels Disengaged
When the reel engage switch is in the O
FF
position or the cutting units are in the
raised position, solenoid proportional valves (SP1) and (SP2) are not energized.
Pump flow causes the pressure to increase, shifting the logic cartridges (LC1)
and (LC2). The pump flow is routed through the shifted logic cartridge and out
of manifold port T1. Return fluid from the manifold is directed to the oil cooler,
return filter, and hydraulic reservoir.
When the reels are disengaged, the inertia load of the spinning reels over run
the reel motors, effectively turning the reel motors into hydraulic pumps. Check
valves (CV1) and (CV2) in the mow circuit will open to keep the reel motor circuit
full of fluid so that the motors will not cavitate (fill with air).
Reelmaster ® 5410/5510/5610 Series Page 6–35 Hydraulic System: Hydraulic Flow Diagrams (5610-D)
15216SL Rev C