The flywheel and clutch disc are in contact to transmit the engine power to the wheels. Rotational motion is transmitted from the engine-flywheel to the gearbox by using a clutch-system which is based on frictional properties.
ACTIVATION OF CLUTCH
When the clutch pedal is loaded, the pressure plate of the clutch system moves away from its position, leaving a considerable gap between itself and the engine-flywheel. (i.e.)Contact between engine and gearbox is now cut-off.
Therefore, no power transmission happens in the clutch-system, but the inertia motion enables the rotation of the wheels until the contact is regained.
Helical spring has been used in the prototype, but diaphragm spring can be used in the similar method for more effective power transmission. On holding the clutch pedal, the contact-breaker pushes the friction plate of the clutch system away from the engine-flywheel. Due to this, the frictional contact between the clutch system and engine-flywheel is broken and no power is transmitted. On releasing the clutch pedal, the spring (which was compressed on holding the pedal) pushes the friction plate to its original position. Contact between the friction plate and the engine-flywheel resumes. Transmission of power resumes.
This clutch activation mechanism promotes rear-engine front-wheeldrive vehicles. REFWD design gives advantages in terms of crash performance by increasing the front crumple zone, allowing greater styling freedom, enhancing the ride quality by reducing the noise, vibration, and harshness, and in lowering the center of gravity providing improved handling, braking and roll characteristics.