Toro Reelmaster 5100-D, Руководство по обслуживанию

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Raise Cutting Units
The “P1” pump circuit controls the raise and lower
function of all five cutting units. On the “P1” pump circuit,
maximum system pressure is limited by relief valve “R1”
which is set at 3000 PSI. System pressure on the “P1”
side can be measured at Port “G1”.
To raise the cutting units, solenoid valve “S7” is ener­
gized to direct pump flow through valve “S6”, a normally
closed poppet-type valve, and on to valves “S3”, “S4”,
and “S5”. These three normally closed valves control
which cutting units raise or lower. To raise a cutting unit,
valve “S7”, and “S3”, “S4” or “S5” must be energized.
The return oil from the cylinders is directed back to tank
externally from the valve block.
To hold the cutting units up in any position, all of the
solenoid valves are de-energized. Valve “S6” is the load
holding valve and this is the reason it is a poppet-type
valve.
The lift speed of No. 1 (front center), and No. 2 and 3
(rear) cutting units is regulated by one-way variable
orifices which are located in the hydraulic lines between
the valve block and lift cylinders.
M4
System Pressure
l
M5
S3A S4A S5A
l
Motors
i
G1
P1 T
G2
VS1
S1
S7
S3
S4
S5
S6
S9
S2
VS2
2 3
4 1 5
le
All i
R1
R2
S8
Pump
Pump
Low Pressure, Return or Case Drain
Oil Flow
Front Ree Motors
Control Valve Block
M2 M3
Rear Ree
Front Lift Cylinders
Rear L ft Cylinders
D1 D2 P2
3000 PSI 2000 PSI
Steering Cylinder
Steering
Valve
Steering
Pump
Variab
Orifice
to port D2
to port D1
Solenoids Energized
Lift Cutt ng Units: S7, S3, S4, S5
250 PSI
Figure 12
Reelmaster
®
5100-D Page 4 - 11 Rev. A Hydraulic Flow Diagrams