Open Tailgate; Close Tailgate - Claas QUANTUM 3500 Service Parts

Hydraulics

4.2.10 Open tailgate

4.2.11 Close tailgate

11-86
QUANTUM
Solenoid valves (12-M3), (20) and (30) are energized.
The volume flow from the pump (10 l/min.) flows to the hydraulic cylinders
(22) via port B of solenoid valve (12) and from there via solenoid valve
(20).
The backside build-up of pressure moves the spool (5) of circulation
valve (4) back against the volume flow.
The oil displaced from the hydraulic cylinders (22) flows back into the
tank via the activated solenoid valve (30) and port A of solenoid valve
(12).
The tailgate is raised.
At the limit stop of the tailgate, the 150 bar oil pressure switch (21)
closes. The control light on the switch console flashes (tailgate open).
When the hydraulic cylinders hit their limit stop, the pressure relief valve
(8) opens. The spool (5) of the circulation valve (4) opens and the volume
flows back into the tank via the circulation valve (4).
When switching off, the solenoid valves (20) and (30) switch first and
then, after a delay, the solenoid valve (12-M3).
Solenoid valves (20) and (30) are energized.
Due to the tailgate's dead weight, the oil from the hydraulic cylinders is
displaced towards the tank via solenoid valve (20) and port B of the
deactivated solenoid valve (12).
When the reed switch is closed, the solenoid valve (12 – M4) switches.
The volume flow (10 l/min.) flows to the hydraulic cylinders (22) via port A
of solenoid valve (12) and from there via the activated solenoid valve
(30).
The backside build-up of pressure moves the spool (5) of circulation
valve (4) back against the volume flow.
The tailgate is locked by pressure.
The oil displaced from the hydraulic cylinders (22) flows back into the
tank via solenoid valve (20) and port B of solenoid valve (12).
Solenoid valves (12-M4), (20) and (30) are deactivated by a clock-
controlled circuit in the module.
TIC
10/04