Infinitely adjustable proportional valve for damping force
Hydraulic proportional valve with pressure feedback for optimizing adaptive suspension damping in semi-active and active suspensions.
This intelligent valve technology describes the premier class of infinitely variable proportional valves: optimization of adaptive suspension damping in semi-active suspensions. Control of the damping force, infinitely variable. Enables damping force adjustment according to the skyhook principle.
Product description
The valve system is the heart of every shock absorber. The proportional valves required for stepless adjustment represent the top class of this type. To this end, RAPA has developed an intelligent damper valve technology with two continuously adjustable control valves in the compression and rebound stages exclusively for the shock absorber manufacturer thyssenkrupp Bilstein – based on the know-how of its previous damper valve developments. These are responsible for regulating the damping force and work as an adjustable hydraulic bypass in the shock absorber. This enables the damper to ensure damping force adjustment according to the skyhook principle even in the high-frequency range of wheel vibrations. One valve controls the rebound stage, i.e. the force when the wheel extends, and the other controls the force in the compression stage. Within a few milliseconds, the control unit responsible for the suspension control adjusts the damping forces for each wheel individually. This increases comfort for the occupants and stabilizes the body in the best possible way. The special design of the valve ensures that the damping force is proportional to the set current. The valve-internal pressure feedback ensures superimposed pressure limitation even with highly dynamic excitations, which further increases ride comfort.
Key features
- Best in class solution for valve map spreading
- Comfort-oriented directional control valve technology
- Low energy consumption
- Outstanding cost-benefit ratio thanks to variable modular valve system
Technical data
- Proportional directional control valve technology with minimal hysteresis and excellent response behavior
- Combined with valve-internal pressure feedback for pressure limitation
- High spread of the valve map
- Harmonic progression of the pressure-flow characteristics
- Compact design
- Design optionally as NO (normally open) and NC (normally close) variant
- Lowest leakage through the valve due to seat seal in closed state
- Lowest pressure loss when open
- External valve, suitable for free installation in the wheel arch
- Low energy consumption
- 100% duty cycle
- Long service life
- Industrialized for large-scale production
Production
Production takes place in a new, modern, high-performance production hall at the main plant in Selb on two fully automated production lines, each consisting of five assembly units. A further line is planned at the RAPA plant in the USA. An essential part of production is the fully automatic quality inspection of each individual valve. All systems are therefore equipped with EOL test benches as standard. Each valve is 100% tested to meet the customer’s hydraulic requirements. For our customers, this means greater safety in all processes and precise quality for highly reliable and precisely fitting products.