Cub Cadet 8404 - Manual (Page 243)

HYDRAULIC SYSTEM
9-9 D615-W02 May-2003
615W911A
6.3 OPERATION PRINCIPLE
• Since the control valve of the hydraulic cylinder is
available to control oil flowing in and out of the hy-
draulic cylinder. It also controls the implement up
and down at a constant speed regardless of the
implement load. A high work performance can be
achieved without impact, along with the operation
principle classified into 3 phases of neutral, deliv-
ery and discharge.
In this phases the control valve keeps on pressure the
oil contained in the cylinder thus allowing the oil com-
ing from the pump to flow freely to the tank.
In this phase the control spool (1) is in such a position
to connect the chamber (15) directly to the discharge
through the hole (16).
The oil coming from the pump will thus be able to move
downward through the small regulator piston (2) and
thus flow to the chamber (22) and by opening the holes
(17) it will flow to the tank.
(1) Control Spool
(2) Regulator Piston
(3) Check Valve
(4) Exhaust Valve
(5) Relief Valve
(15) Chamber
(16) Hole
(17) Hole
(18) Annular Duct
(22) Chamber
(23) Cylinder Chamber
A. Neutral Phase
The oil contained in the cylinder (Chamber 23) is kept
on pressure by the check valve (3), by the discharge
valve (4) and by the relief valve (5) connected to the
cylinder by annular duct (18) thus holding the load ap-
plied to the lifting.
The relief valve (15) secures protection from any pos-
sible overpressure.