Valve block
The valve block for Dynamic Drive is installed behind the right front wheel well. The valve block is electrically connected to the VDM control unit. The stabilizers on the front and rear axles are split and connected in the center to a swivel motor. The swivel motors are hydraulically activated via the valve block. This enables very rapid application of a defined torque onto the stabilizer in the desired direction.
| Item | Explanation |
|---|---|
| 1 | Pressure control valve for front axle (2-pin plug connection) |
| 2 | Shift-position sensor (3-pin plug connection) |
| 3 | Pressure control valve for rear axle (2-pin plug connection) |
| 4 | Valve block |
| 5 | Safety valve (2-pin plug connection) |
| 6 | Direction valve (2-pin plug connection) |
| 7 | Pressure sensor for rear axle (3-pin plug connection) |
| 8 | Pressure sensor for front axle 3-pin plug connection) |
The valve block is located in the right front wheel arch near the A-pillar.
The following components of the valve block are described:
Front and rear pressure-control valves
The pressure-control valves are located within the valve block. The pressure control valves are activated by the VDM control unit. In the process, the hydraulic pressure (differential pressure) is set for the stabilizers (up to 180 bar). When the vehicle is being driven straight ahead, the pressure control valves are applied with preliminary current (0.35 Ampere). The oil flow flows freely to the oil reservoir. On cornering, the pressure control valves are supplied with current. The hydraulic pressure in the swivel motors is regulated to the setpoint value. Due to factors inherent in the design, the hydraulic pressure on the swivel motor of the front axle is greater than or equal to the hydraulic pressure at the swivel motor of the rear axle.
Front and rear pressure sensors
The pressure sensors monitor the hydraulic pressure to the stabilizers on the front and rear suspensions. The sensor signals (tension) are routed to the VDM control unit. The pressure in the return line to the oil reservoir is not monitored (circulating flow approx. 2 bar).
Direction valve
The directional-control valve is governed by the VDM control unit. The direction valve sets the direction of the hydraulic fluid for right-hand and left-hand bends as well as of the return flow of oil. The 4-2 directional control valve "swaps" the pressure side towards the stabilizer. The direction valve is the component of the active roll stabilization where safety is most critical. This is why the direction valve is monitored by a separate sensor.
, shift position sensor
The position sensor monitors the position of the directional-control valve. The shift-position sensor works according to the Hall effect. There is a magnetic hollow cylinder at the direction valve into which the shift-position sensor protrudes. This enables the shift-position sensor to detect the following 2 positions: no activation, activation curve (0.7 Volt, intermediate range 3.0 Volt, 4.2 Volt). The sensor signals are routed to the VDM control unit.
Safety valve
The safety valve is controlled by the VDM control unit, and closes off the front suspension swivel motor when not under power (hydraulic blocking). The safety valve is de-energised under the following conditions: Open circuit in the voltage supply and system fault. The rear axle swivel motor is connected hydraulically and by the return line to the oil reservoir. This limits the system pressure and creates a circulating flow.