Toro Pro Sweep 5200, Service Manual

Page: 25 / 77

Hopper Dump/Lower Circuits
NOTE: Hydraulic flow and relief pressure to the Pro
Sweep 5200 are determined by the tow vehicle.
Hydraulic flow from the tow vehicle goes to the control
manifold (port P) through the hydraulic input hose.
When the sweeper brush motor is not engaged and the
lift cylinder is stationary, hydraulic flow from the vehicle
is directed by the un–energized demand solenoid valve
(S2) to return to the tow vehicle through control manifold
port T and the return to tank hose.
Hopper Dump
When the hopper switch is pressed to dump, both the
hopper up (S1) and demand (S2) solenoid valves in the
hydraulic control manifold are energized. The valve shift
of S2 prevents hydraulic flow return to the tow vehicle.
The valve shift of S1 allows oil flow past the check valve
in the control manifold, out of control manifold port CYL
and to the lift cylinder. Hydraulic pressure against the lift
cylinder rod extends the cylinder and dumps the hopper.
The check valve fitting attached to the lift cylinder allows
oil flow to bypass the orifice in the fitting for proper lift cyl-
inder extension.
When the hopper switch is released, solenoid valves S1
and S2 in the hydraulic manifold are de–energized. The
load holding check valve in the control manifold and the
de–energized solenoid valve S4 prevent oil flow from
the lift cylinder so the hopper remains in the raised
(dump) position.
Hopper Lower
When the hopper switch is pressed to lower, the hopper
down (S4) solenoid valve in the hydraulic control man-
ifold is energized. The valve shift of S4 allows a path for
oil flow from the lift cylinder. The weight of the dump hop-
per and frame cause the lift cylinder to retract and the
dump hopper to lower. Oil flow from the retracting lift cyl-
inder returns to the control manifold port CYL, past S4,
out manifold port T and returns to the tow vehicle. The
orifice in the lift cylinder check valve fitting restricts oil
flow from the cylinder to provide for proper lift cylinder
retraction speed.
While lowering, if the hopper switch is released, sole-
noid valve S4 will de–energize and oil flow from the lift
cylinder will cease. The hopper will remain in the partial-
ly lowered position.
Hydraulic System
Pro Sweep 5200 Page 3 – 9 Hydraulic System