A clutch is a device used for producing a rotating mechanism. Clutches are commonly found in vehicle transmissions and are used to connect two rotating shafts. In this system, one shaft is driven by a motor or pulley, and the second shaft is used to drive another device. The clutch allows the shafts to spin at the same time, a cycle referred to as engaged, or to be disconnected and spin at different speeds, known as disengaged.
Clutches are required in vehicles to enable the engine to continue spinning even when the wheels are not. The clutch facilitates a smooth slippage between the spinning engine and the non-spinning transmission. To achieve this, the clutch attaches the flywheel to the engine, while the clutch plate attaches to the vehicle’s transmission. When the driver releases pressure on the foot pedal, springs push the pressure plate against the clutch, which touch the flywheel. This action locks the engine to the transmissions input shaft and the two devices begin to spin at the same speed.
The friction created between the flywheel and the clutch plate determines the amount of force that the clutch can hold. Hydraulic or cable pistons are used to push on the release fork when the clutch pedal is engaged, causing the throw-out bearing to touch the diaphragm springs. When this occurs, a set of pins causes the springs to touch the pressure plate and disconnect from the clutch disc. This action disengages the clutch from the spinning engine.
Clutches tend to experience wear and tear after time. Modern cars can typically run for 80,000 miles (128,748 km) before the clutch’s effectiveness starts to deteriorate. One of the most common problems is caused by the friction of the clutch plate. When the friction is affected, the clutch will slip and will not be able to transmit any power between the engine and the wheels. A related problem is sticking, occurring when the clutch is broken, leaky, or using mismatched parts.
The clutch is a crucial component not only to the operation of a vehicle, but also to other devices within it. A vehicle alone has several sets of clutches it relies on: automatic transmissions, air conditioning, fans, limited slip differentials, and more.