What is the principle of the clutch?

[Remington]

Clutch works as follows: The torque generated by the engine is transmitted to the driven plate through the friction between the flywheel, pressure plate, and the contact surface of the driven plate. When the driver depresses the clutch pedal, the diaphragm spring's large end moves the pressure plate backward through mechanical transmission, separating the driven part from the driving part. During vehicle operation, the driver can depress or release the clutch pedal as needed to temporarily disconnect or gradually engage the engine with the transmission, thereby cutting off or transmitting the engine's power to the transmission. The clutch is a common component in mechanical transmission systems, allowing the drivetrain to be disconnected or engaged at any time.