A clutch is a mechanical devices which helps to engage or disengage from the engine without stopping the m/c or vehicle. In other words, the clutch is the connection point for the engine and the transmission; the torque converter of manual transmission. The best way to explain it will be that when we drive a vehicle, to increase/decrease the speed we need to change the gear. In order to change the gear, we do not stop the vehicle or m/c but instead press the clutch, which dis engages the gear and then applies the gear which is required. Thus without stopping the m/c or vehicle, its speed can be increased or decreased.
Now, one may thing about the automatic gear vehical like Activa or the automatic transmission vehicle which does automatic gear change by just increasing/decreasing the accelerator but in this case the clutch is part of a larger series of systems that comes together to form the torque converter, rather than the clutch you find in a manual transmission car. The torque converter connects the engine to the transmission so that the wheels will turn, similar to how a clutch in a manual transmission bike/car functions.
A clutch is made up of several important components:
1. Pressure Plate - This is secured to the flywheel via bolts. During engagement, The pressure plate clamps with the flywheel thereby transmitting the power to the transmission. During disengaging, It lifts away from flywheel thereby making gap for the clutch disc to disengage from the flywheel and helping the shift gear.
2. Clutch Disc - This is mounted to the input shaft, between pressure plate and flywheel. During engagement of clutch, the Disc moves forward and clamps solidly between pressure plate and flywheel. During disengagement, the pressure plate lifts and though the pressure plate and flywheel rotates, the clutch disk and the input shaft is no longer rotating.
3. Pilot Bushing - It acts as a guide and seat for the shaft during the engagement and disengagement.
4. Throwout Bearing - These are used to push forward and compress the pressure plate against the flywheel and vise-versa during the engagement and disengagement of the clutch system. Depending upon the system and function, it is designed in different shapes and sizes.
There are various types of Clutches :
1. Basic Friction clutch
2. Wet and Dry clutch
3. Multiplate clutch
4. Dual-clutch system
5. Electromagnetic and Electro Hydraulic clutch.
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