August 2014 August | Page 36

special feature: drivetrain SACHS Clutch Disc with Torsional Damper SACHS, a brand of ZF, demonstrates expertise in generating comprehensive solutions with its integrated powertrain systems. ZF pursues a systems approach in developing and manufacturing new products and technologies that represent real advances. ZF provides overall solutions that meet the demands of overall systems. Torsional dampers are individually tuned because each engine/transmission aggregate has its own characteristics. The resulting superior spring and damping characteristics generate outstanding decoupling qualities. Peace and Quiet in the Powertrain Clutch discs are subject to immense loads during the vehicle’s life cycle, and are complex components w ith compact dimensions. Besides transmitting torque, they have additional tasks such as damping torsional vibrations, ensuring good operating comfort, and offering high thermal resistance. Clutch facings: Long-lasting and environmentally friendly By enabling carefully calibrated sippage in the launch phase, the friction facings and cashion springs allow precision torque calibration and are therefore responsible for the gentle clutch engagement needed to start vehicles smoothly. Function: The task Ignition-induced irregularities in rotational speed and rapid load alterations generate vibrations in the powertrain, which in turn cause disturbing noises in the vehicle body and unpleasant rattling in the transmission. Modern engines are featuring smaller displacements and supercharging (down-sizing) in order to reduce fuel consumption. These engines generate high levels of torque at low rpm levels (down-speeding) This constellation of engine characteristics leads to an increase in torsional vibrations. Yet drivers continue to demand higher performance from their damping systems. Benefits: The technology The torsional damper integrated in the clutch disc is the main element for adjusting torsional rotation properties throughout the powertrain, from the combustion engine to the wheels. This effective vibrational damping system consists of a friction unit and spring sets for both driving and idling. Coil springs positioned in windows allow a limited degree of rotation between the crankshaft and the transmission input shaft. | words in action 34 august 2014 Clutch facings are made of a number of carefully matched materials: glass or aramid fiber together with copper brass wire, embedded in a mixture of resin, rubber, and fillers. Especially when launching under tough conditions, but also under normal driving operations, the facings subjected to high friction speeds, strong clamp loads, and extremely high temperatures. During all these types of conditions, drivers still expect full performance. Clutch facings from ZF contain no lead and are manufactured via environmentally friendly processes and comply with EU vehicle recycling regulations.