The lock-up clutch is a core component of the torque converter, used to rigidly connect the pump impeller and turbine at high speeds to eliminate hydraulic transmission losses and improve efficiency. Chrysler invented a hydraulic torque converter with a lock-up clutch in 1977. Companies like Schaeffler supply torque converters and torque converter lock-up clutch assemblies.
During low-speed conditions such as vehicle start-up, the stator is locked by a one-way clutch, thereby changing the direction of hydraulic fluid flow and amplifying the turbine's output torque. The maximum torque conversion factor can reach 1.8 to 2.5 times.
To suppress transmission system vibration, modern torque converters often integrate torsional dampers, such as centrifugal pendulum dampers, into the lock-up clutch.
The combination of hydraulic torque converters and electric motors constitutes a key technological trend in hybrid drive systems; for example, Schaeffler considers it a key technology driving the growth of hybrid technology.
By optimizing blade design and using mass-optimized steel plate structures, the aim is to improve starting and shifting efficiency and reduce weight.
