Manual transmission cars have several clutches, automatic transmission cars also have clutches and other several devices which we use for work, for example drills, chains saws, yo-yos and other have different kind of clutch device.
Clutches are devices that connect the engine to the transmission. If we want to change the speed of the car without getting into any problems while driving we need to decouple the engine from the wheels. The engine rotates constant and the wheels do not, to change the speed we first need to un mount the wheel from the engine, using the clutch, and the connect it again for smooth transmission between different speeds.
The main parts from which the clutch is constructed of is the flywheel, clutch plate and the pressure plate. The flywheel is connected to the engine, clutch plate is connected to the transmission and the pressure plate goes on top.
Construction of the full clutch goes like this: flywheel, clutch disk, pressure plate, studs, diaphragm, throw out bearing, clutch housing, clutch housing, release fork, bell housing. After that follows the transmission box.
The clutch works because of the friction between the clutch plate and the flywheel.
Every mechanical device after a while could show signs of some problems. The most common problems that could appear to clutches are wearing off, of the friction material, broken or stretched clutch cable, leaky or defective slave or master clutch cylinders, air in the hydraulic line, miss adjusted linkage, mismatched clutch components.
There are different types of car clutches. Air conditioning in a car has an electromagnetic clutch, which shuts down the compressor while the engine is working. Cars with engine- driven cooling fan have thermostatically controlled viscous clutch. Gas powered chainsaws have centrifugal clutches. With it you can stop the spinning of the chains and strings without the need to turn off the engine of the chainsaw.