The system in the picture is composed of three components:
– Power Pack
– Hydraulic Transmitter
That allows the manoeuvre of the three systems: Hydraulic FU, Electric NFU, Hydraulic Manual/Emergency.
Is composed of the Main cylinder and a Feedback cylinder mounted in parallel with the same stroke.
In FU mode, the feedback cylinder is filled by the manual movement of the Transmitter, where the pressure to the servo valve feeds the main cylinder.
The control is step by step and direct.
In NFU mode, the main cylinder is fed directly through the command of a solenoid valve, whereas the feedback cylinder is put into standby by the simultaneous command of a second solenoid valve.
In Manual/Emergency mode, the main cylinder is fed directly by the manual transmitter, whereas the feedback cylinder is put into standby through the antishock valve.
Is the heart of the system, where the motor-pump and control /command valves are grouped.
When the power pack is switched on, the FU and NFU systems are automatically available simultaneously by use of the transmitter or joystick/autopilot.
In case of a power failure or the switching off of the power pack, the system switches automatically over to the Manual/Emergency system.
In this case an electric selector puts the transmitter into direct contact with the cylinder actuator, allowing an automatic manoeuvre.
The power pack has automatic filling of the system and manoeuvre time regulation during NFU mode.
The manual axial-piston pump with steering wheel is used for the servo- assisted and manual system.
The main cylinder is hydraulically independent from the feedback cylinder, thus preventing the feedback cylinder from being overloaded at the work pressure value during emergency.
This system is preferable to the traditional Orbitrol as it is more silent (it does not send pressurized oil to the bridge), allowing safer and better manoeuvring.