Definition of Centrifugal Clutch:
Centrifugal clutch mainly uses centrifugal force to engage other clutches or build connections between transition shaft and engine drive shaft. This clutch can be placed between the transition system and engine flywheel. According to the engine speed, it is usually operated automatically. There is no requirement of a clutch paddle in a vehicle, to move the clutch. Without gear up or gear down, a driver can start or stop an engine. The centrifugal clutch is more efficient when it is at high speed.
Different Parts of Centrifugal Clutch:
Following are the mains parts of a Centrifugal Clutch :
1. Shoes:
Shoes can be used as friction consumers. It is mainly designed to slide. These shoes are attached between the guides. At the end of the shoes, they have friction lining. At the time of engagement, with the drum, this friction lining can be used to make contact.
2. Spring:
Spring is a controlling element here. Spring can be usually used at a time of lower speed. Spring is attached to each shoe. With the help of this spring, shoes are attached with the guide. When the engine rotates at a low speed then the clutch is needed to be disengaged. Here the Spring disengages the clutch. Otherwise, spring holds the shoe in the initial position since the proper speed is not achieved. Higher indexed springs are required when the engaging speed is needed to be the changed.
3. Spider or Guides:
The spider is placed on the motor shaft or on the driver (engine) shaft. The space between spiders is equal. The distance between each guide is the same. Example, let us consider there are three guides present then for each guide, the next guide is separated by 90 degrees from that. Between these guides, the shoes are kept to consume the frictions between these guides. Each guide consists of a spring to disengage the clutch.
4. Friction Lining:
The Friction lining is a part of the sliding shoes. Friction lining works on the same principle as the friction plate of a simple clutch works. With the end of the outer surface of shoes, this friction lining can be attached. Friction lining transmits torque. It helps to make a grip on the drum’s inner surface. It avoids the direct contact of the sliding shoes by the drum. It reduces the wear and tear of the sliding shoes.
5. Drum:
The Drum works as the housing component in the clutch. All the clutch parts, like guides, sliding shoes, springs, friction lining and others are surrounded by the Drum. The drum is attached with the driven shaft of the belt, chain or the transmission system.
Working Principle of Centrifugal Clutch:
Centrifugal clutch mainly works on the principles of two forces. They are Centrifugal Force and Friction Force. Centrifugal Force is a type of force that is created on a rotating body and pulls the body which is rotating from its center. On the other hand, the Friction Force is the force that is created between two surfaces of other bodies when they are moving on the opposite side of each other.
Centrifugal clutch can be used to connect the accelerated load with the power sources (turbine, motor, engine and others). The working of the Centrifugal clutch varies according to the amount of Centrifugal force made by a driving member (motor or engine). Centrifugal clutch mainly attaches other clutches or engages the driven shaft with the clutches.
When the engine starts to rotate then the Centrifugal force is produced. This centrifugal force turns the driveshaft. It also activates the transmission depending on the enhancement of the engine rpm.
The size of the clutch is developed according to the load but in that case, the motors’ horse power cannot be considered anytime. Alongside, a small-sized motor can also be utilized in order to generate the maximum torque. Also, the size of the gear reducer is small.
The Centrifugal force can also be used to push the sliding shoes outward. Then the friction lining of the shoes makes a connection with the drum’s inner surface. So, the drum starts to move. The drum is then attached to the driven shaft. At first, it helps to transmit the power to the transmission shaft from the engine shaft and then to the load.
Centrifugal clutch makes sure that the current drawn is minimum and the torque generated is maximum. Due to less amount of heat emissions the clutch plate does not slip through which the load can be accelerated. Also, the motor is safe due to the low amount of heat dissipation. Oftentimes it is found that due to high heat, motor get’s burnt and that is not good for any machinery around the manufacturing industry.
Advantages of Centrifugal Clutch:
There are many reasons present to choose the centrifugal clutch as an alternative. These reasons can be considered as the advantages of the Centrifugal clutch. They are as follows:
- Centrifugal clutch does the work of engaging and disengaging automatically. So there is no necessity or requirement of any other kind of mechanical part to control the peak speed of the engine. The working principle of the centrifugal clutch is mainly based on the law of physics.
- In comparison with other clutches, the cost of the Centrifugal clutch is much lower. In the case of the Centrifugal clutch, fewer parts are involved. No battery or extra component is needed to assist the Centrifugal clutch to perform the function properly.
- The servicing and maintenance cost of the centrifugal clutch is low. As the construction and primary design is good so there is a little chance of break down of the system. As the construction and design of this clutch are sound at the initial stage so there are minimal chances for it to be damaged. So, users of this clutch have to expend a little extra money for maintenance and servicing. Therefore, it is more cost-effective.
- Overloading and abrupt starting can create a burden on the engine which causes damage to the engine. In the case of a centrifugal clutch, it is better and safer than the others with load and progressive engagement. Centrifugal clutch is mainly specialized to perform shock less and smooth acceleration.
- The centrifugal clutch can control the speed of the engine. This clutch has a greater progressive engagement and it’s feature helps in increasing the torque, a twisting force moving toward the load from the engine.
- The centrifugal clutch having the feature of greater engagement and speed control enhances the lifespan and excess energy accumulation on the startup.
Disadvantages of Centrifugal Clutch:
There are many disadvantages of the Centrifugal Clutch which are as follows:
- Though the centrifugal clutch has many benefits yet this clutch is not suitable for all applications on all occasions. The user must be aware about the fact of a lack of experience on applications of a centrifugal clutch.
- The transmission power of the centrifugal clutch has limitations because of slippage. In the case of an engine with a low RPM, centrifugal clutch is not suitable because of the overheating problem. More heat can be produced due to friction between shoes and clutch drum. This problem of overheating can damage the clutch due to slippage and loss of power.
- Various sizes of clutch create a different amount of peak speed. The clutch is smaller in size and produces a faster speed. This happens due to the centrifugal force that is needed to be engaged.
- The clutch is activated when an engine reaches a particular speed. If the engine wants to attain a certain speed the clutch does not work properly. If loading capacity goes beyond the capability of the clutch, it loses its performance which leads to slippage. Due to this problem engine cannot perform properly causing damage to the engine. So, the centrifugal clutch is suitable for an engine having high speed but not for a lower speed engine. So, the centrifugal clutch protects driven equipment and saves the engine with a vast range of speed.
- Centrifugal clutch cannot create high torque.
- High power loss is present, during the slipping and friction.
- In the case of vehicles, high heat is produced due to bad driving habits. This overheating may damage the clutch completely.
Applications of Centrifugal Clutch:
There are many applications of the Centrifugal Clutch which are as follows:
- Centrifugal clutch is generally used in vehicles.
- Centrifugal clutch is widely used in industrial applications like machinery, mining, military, manufacturing purposes.
- In chemical industries, the Centrifugal clutch is used in mixers.
- Used in lawn movers, chain saw.
- Used in scooters, go-karts, and mopeds.
- During stalling, in paramotors and boats, a Centrifugal clutch.
References
- How Clutches Work | HowStuffWorks – Auto | HowStuffWorks
- How a car clutch works | How a Car Works
