The core business of LuK – the abbreviation for “Construction of disks and clutches” – is historically part of the clutches, related systems and dampers in the transmission line. The rise of LuK began with the series of disc springs clutches. Today the offer is much wider. Behind the clutch system concept there is, in addition to the developments in the wear recovery friction sector, also the global complex “clutch and drive”, in short disengagement systems.
LUK CLUTCH SYSTEMS
The clutch disc is the main connecting element of the clutch. Together with the clutch pressure plate, the clutch disc disconnects and reconnects the engine from the drivetrain. When doing this, the clutch disc acts as a frictional partner between the flywheel and pressure plate.
Clutch facings are employed here to adjust engine speed to that of transmission speed, and transfer engine torque. And a damping system in the hub is used to prevent engine vibration from being transferred to the drivetrain.
CLUTCH PRESSURE PLATE
The clutch pressure plate, together with the flywheel and the clutch disc, form a friction system and is mounted to the flywheel via the bolts of the housing. It employs a release system to interrupt and reconnect the flow of power from the engine to the transmission.
The clutch pressure plate consists of the following components – the clutch housing, pressure plate, diaphragm spring and tangential leaf spring.
SELF-ADJUSTING CLUTCHES (SAC)
When the clutch disc wears down, more pedal force is required to release the clutch. A self-adjusting clutch (SAC) provides automatic wear compensation and ensures that the force needed to press the clutch pedal remains low over the entire service life of the clutch.
There are two types of self-adjustment – force controlled and travel controlled. The force controlled SAC’s wear compensation is activated by a load sensor (sensor diaphragm spring) that turns a ramp ring. The ramp ring of a travel controlled SAC, however, is turned by an adjusting mechanism which is activated by the wear related decrease of the clutch release path.
DUAL MASS FLYWHEEL
Vibrations that occur in the drivetrain of a vehicle can be heard as low engine-speed rattle and droning. To counteract this, LuK developed the dual-mass flywheel and made it production-ready back in 1985. It reduces vibrations in the drivetrain and delivers smooth operation.
A conventional flywheel consists of a single rigid part. A DMF, on the other hand, consists of two masses mounted so they can rotate against each other.
DFC (DAMPED FLYWHEEL CLUTCH)
The DFC is based on the proven dual-mass flywheel but with clutch disc, pressure plate and crankshaft bolts integrated into a single, compact module that simplifies installation.
The entire module is delivered as a single unit and can be mounted directly to the crankshaft. The crankshaft bolts can be tightened through openings in the diaphragm spring, the clutch pressure plate and the clutch disc.
To ensure smooth engine operation, a large rotating mass – the flywheel – is mounted to the crankshaft. Its main function is to store kinetic energy briefly before releasing it smoothly and evenly.
But the flywheel also plays an important role in power transmission. It is part of the clutch assembly, and one of its sides serves as the friction coupling surface for the clutch linings.