Document 57.4402.8200 - 1
st
Edition 03/2007
INDEX
GYRO 4020 - 4518
INTRODUCTION
x
The solenoid valve n. 1 of block (
81
) controls the
cylinder (
82
) operating the rear left stabilising foot.
This cylinder is equipped with a double-acting
compensation valve (
83
) used also as safety valve.
On the rod side of this cylinder, there is a pressure
gauge (
84
) calibrated to 50 bar which detects when the
outrigger is lowered to the ground.
The solenoid valve n. 2 of block (
81
) controls the
extension cylinder (
85
) of the rear left outrigger.
This cylinder is equipped with a double one-way valve
with hydraulic release, acting as a safety valve (
86
).
The solenoid valve n. 3 of block (
81
) controls the
extension cylinder (
87
) of the rear right outrigger.
This cylinder is equipped with a double one-way valve
with hydraulic release, acting as a safety valve (
88
).
The solenoid valve n. 4 of block (
81
) controls the cylinder
(
89
) operating the rear right stabilising foot.
This cylinder is equipped with a double-acting
compensation valve (
90
) used also as safety valve.
On the rod side of this cylinder, there is a pressure
gauge (
91
) calibrated to 50 bar which detects when the
outrigger is lowered to the ground.
The differential anti-slip circuit is controlled by the 3-
way/2-position solenoid valve (
69
). When this valve
is not energised, the service brake control line of the
front axle (
57
), coming from the SAFIM braking system
(
35
) through port 5 of the hydraulic rotary joint (
9
), is
connected to the service brake ports of the front axle
(
57
). On the contrary, when valve (
69
) is energised, a
condition corresponding to the anti-slip control "ON", the
service brake ports of the front axle (
57
) are connected
to the 25-30bar low-pressure line and help the action of
the differential anti-slip system.
The oscillation of the front axle (
57
) is controlled by two
cylinders (
60
-
63
) equipped with block solenoid valves
(
61
-
62
). The movement of cylinders (
60
-
63
), and thus
the front axle oscillation (
57
), is only possible when
solenoid valves (
61
-
62
) are energised.
The frame levelling is controlled by a 4-way/3-position
ON/OFF solenoid valve (
59
) which feeds in a crossed
manner the cylinders (
60
-
63
).
This solenoid valve, through port 3 of the hydraulic rotary
joint (
9
), is activated by the simultaneous operation of
the 4
th
element of the electro-proportional main valve (
8
)
and of the electric divider (
22
).
The oscillation of the rear axle (
58
) is controlled by two
cylinders (
65
-
68
) equipped with block solenoid valves
(
66
-
67
). The movement of cylinders (
65
-
68
), and thus
the rear axle oscillation (
58
), is only possible when
solenoid valves (
66
-
67
) are energised.
The flow control valve (
64
) allows for the free passage
of the oil coming from the drive drain circuit during the
filling of the cylinders (
65
-
68
) (air venting) and avoids
pressure peaks in the circuit of such cylinders when high
oscillation speed conditions of the rear axle produce
potentially dangerous overpressures in the drive drain
