Chassis suspension springs are crucial for vehicle ride characteristics. In conjunction with shock absorbers, suspension springs improve the ride comfort and handling safety of modern vehicles. The automobile industry places extremely high demands on quality and cost-effectiveness.
Valve springs are helical springs made of pure cold-formed high-tensile spring steel. As these are the most heavily stressed of all automotive springs, they must be of top quality. Minimal force tolerances, the highest possible fatigue limit and an extremely low relaxation tendency are essential for optimum valve operation and long engine life.
Due to the helix of the spring, loading of the spring ends is not uniform around the circumference. The line of action of the resulting forces does not follow the geometrical centerline of the spring. There are many more transverse forces and moments in the spring installation that lead to friction and wear of other components, e.g. struts, brake cylinders, and valves. That is why it is important to be able to measure the line of resultant force and the transverse forces and moments with a test fixture.
Some examples of the automotive spring testing solutions offered by ZwickRoell
Multi-Channel Spring Testing
Multi-channel measuring platforms allow the force vector of compression coil to be determined. Standard testing systems are equipped with a six- or nine-component force measuring platform for this. This enables the specific determination of the spring penetration points and the resulting force from the force components when loading the spring under compressive force.
Multi-axial loading of pneumatic springs to EN 13597
This testing system supports quality assurance and the development of pneumatic springs. It consists of a floor-standing testing machine. It is equipped with an additional horizontal, electromechanical drive and a force measuring platform with five load cells (3 vertical and 2 horizontal). The axial and horizontal stiffness characteristics of pneumatic springs are determined under vertical, horizontal or combined loading.
Multi-Axial Testing of Struts
This testing system is equipped with three test axes to measure the damping characteristics of the hydraulic shock absorbers. The vertical force (wheel load) is applied by the testing machine axis. Horizontal forces and torsion moments that occur when maneuvering curves, approaching, and braking, etc. are generated through a horizontally affixed single testing actuator and a torsion drive. The test axes can be individually and independently controlled from one another. This way you can determine the characteristics (damping friction, viscosity) at different axial speeds with and without lateral forces and torque.