Front suspension (Actuators): Description and operation

The valve block directs hydraulic pressure to the actuators via solenoid operated directional control valves. A solenoid operated pressure control valve regulates the required pressure to the actuators. The three valve solenoids are controlled by signals received from the ACE ECU. A pressure transducer monitors the pressure delivered by the pump. A replacable high pressure filter is installed into the lower face of the valve block and filters fluid before it reaches the valves.

The valve block is located on the outside of the right hand chassis longitudinal. The valve block is secured to the chassis with three bolts and rubber bushes. The rubber bushes isolate the valve block from the chassis, preventing hydraulic noise from the valve block transmitting through the chassis and body.

The two solenoid operated directional control valves (DCV's) are fitted to ports in the top face of the valve block. The DCV's are screwed into the valve block and sealed with O ring seals. Each DCV has a solenoid for electrical operation of the valve. The solenoid is sealed to the DCV with two O ring and secured with a cap. The cap, coil and O rings are serviceable items. The DCV's are non-serviceable and failure of a DCV requires the replacement of the valve block assembly.

The pressure control valve is fitted to a port in the rear face of the valve block. The pressure control valve is screwed into the valve block and sealed with O rings. The pressure control valve has a coil for electrical operation. The coil is sealed to the pressure control valve with two O rings and secured with a cap. The cap, coil and O rings are serviceable items. The pressure control valve is non-serviceable and failure requires replacement of the valve block assembly.

The pressure transducer is fitted to a port in the forward face of the valve block. The pressure transducer is screwed into the valve block and sealed with an O ring seal. The pressure transducer is a serviceable item.

The high pressure filter locates in a port on the lower face of the valve block. The gauze and fibre filter is sealed in the port with O ring seals. A threaded cap secures the filter in the valve block and is also sealed with an O ring seal. A threaded hole on the lower face of the filter allows a bolt to be fitted to remove the filter from the port. If a system component is replaced, the filter must be changed.

Four ports are located on the forward face of the valve block and two ports on the rear. Each port is fitted with a seal pack which contains two O ring seals and backing rings. The ACE pipes locate and seal in the seal packs and are secured to the valve block with the studs and nuts located on the forward and rear faces.

Actuators

Two actuators are used for the ACE system and are attached to the front and rear torsion bars. The actuators apply hydraulically generated force to the torsion bar to oppose lateral forces caused by the vehicle cornering.

Each actuator is a conventional double-acting cylinder. A piston is attached to a rod and moves within the cylinder when hydraulic pressure is applied. The rod is sealed at the point where it exits the cylinder. The outer end of the rod is threaded and locates in a bush in the ACE long arm and secured with a nut. A rubber gaiter covers the rod and prevents dirt and moisture from damaging the rod surface and cylinder seals. The cylinder has a forked attachment which locates on the short arm bush and secured with a bolt and nut.

Two banjo connections provide for the attachment of the hydraulic hoses from the ACE valve block. The connections provide hydraulic flow to each side of the piston to extend or retract the rod.