What is Braking System : Types and Their Working

In a vehicle, the brake is the most important device to control the vehicle. It reduces the speed of any rotating parts of electrical and mechanical equipment. It is a crucial part of the safe operation of systems. It uses friction on the two surfaces of a vehicle. This converts kinetic energy into heat. Almost all the vehicle wheels have a braking system. Even shopping cars and aircraft have braking systems. It has several characteristics like peak force, fade, continuous part dissipation, power, smoothness, noise, weight, durability, drag, pedal feel. Foundation components at the wheels are the basis for forming the braking system. These are of three types such as wedge brakes, disc brakes, and cam brakes. This article describes all the types of barking systems.

What is Braking System?

Definition: Brake is a mechanical device. From a moving system, it absorbs energy and inhibits motion. It is used for reducing the speed of a wheel or axle. It works by means of friction. The maximum decelerating effect obtained is called peak force, which is the main characteristic of the braking system. The temperature of brakes gets high when they are typically used and this may lead to failure of the system.

Types of Braking Systems

There are three types of braking systems which include the following.

Mechanical Braking System.

• Drum braking
• Disk braking
• Band braking
• Pawl and Ratchet braking

Electrical braking system

• Plugging type braking
• DC injection type braking
• Eddy current braking
• Dynamic resistor type braking
• Regenerative braking
• Sharing DC bus type braking

Other Types of Braking Systems

• Hydraulic braking system
• Power brakes
• Air braking system
• Air hydraulic braking system
• Vacuum brakes/ servo braking system

Some of them are explained below.

Mechanical Braking System

Mechanical braking mostly used in scooters, motor vehicles, and motorcycles where small power is required. It is essential in manufacturing power transmission applications, material handling, etc. It delivers forces to the axle or a wheel in order to stop motion. It helps to reduce the speed of the system slowly by the mechanical process when compared to electrical braking.

The working of a mechanical brake depends on the pedal. When the pedal is pressed, the brake shoes are pushed outwards and rotates against the drum which is connected to the wheels. Hence the machine or vehicle gets slow down and stopped. And when the pedal is released, it goes to normal position due to the pullback action of spring shoes.

Electrical Braking System

Electrical braking is used to reduce the speed of the machine depending on flux and torque. This type of braking is mainly used for functional braking to control the speed of the machine. It is easy to handle and comfortable. But it cannot be used for emergency braking and parking braking.

The working of electrical braking depends on the electromagnetic force (EMF) acting on the brake shoes. The battery is used to generate an electric current which helps to energize the electromagnet mounted on the backplate. This results in activating the cam and expanding the brake shoes. Hence the vehicle or machine is stopped by braking the wheel.

Regenerative Braking

It is one of the types of electrical braking system. When the speed of the motor is increased than the synchronous speed, then the regenerative braking is used. When the rotor rotates higher than the speed of the synchronous speed, then the motor acts as a generator and the directions of current flow and the torque are reversed. Hence the generator is stopped by braking. The main disadvantage is, when the motor exceeds the synchronous speed, it is possible of mechanical and electrical damage. So, regenerative braking can be done at the sub-synchronous speed only when the variable frequency source is applied.

An inverter is used to return excess energy back to the three-phase supply rather than the dissipation of energy in the resistor. To drive the variable frequency systems, an inverter is connected in parallel to the rectifier. The regenerative braking is mainly used in electric vehicles.

Plugging type Braking

It is also one of the types of electro braking system. In this type, the pedal is used for braking the vehicle. When the pedal is pressed, the speed of the electric vehicle is reduced by changing the polarity and direction of the motor. The direction of the motor gets reversed and inturn causes braking the wheel.
In generators, the use of the plugging type braking system results in decreased speed due to the reversal of terminals of the supply, reversal of torque, and restriction of rotation of the motor. An external resistor is used to limit the current flowing through the plugging circuit. The more power is wasted during the plugging.

Dynamic Braking

It is also known as dynamic resistor braking or dynamic rheostat braking. In this type, the resistance is provided to the motor by the rheostat connected to the circuit is capable of acceleration or deceleration of the vehicle. This resistance helps to reduce the speed and stops the electric vehicle. The resistor or rheostat in the circuit dissipates excess energy on the capacitor by connecting a resistor in parallel with the capacitor.

When the motor acts as a generator, reverse current flows through the circuit, and the torque changes and causes braking. The resistance in the circuit can be removed to maintain the constant torque while braking the motor.

Hydraulic Braking

The hydraulic braking system uses liquid as a pressure for the movement or force or to increase the force. The pressure applied on a liquid can be called as hydraulic pressure. This type of braking system works on the principle of pascal’s law. In this type, when the force is applied on the pedal, it is converted to hydraulic pressure by using a master cylinder/liquid. This hydraulic pressure helps in braking the vehicle by transferring pressure to the final brake drum or disc rotor via braking lines. It ensures that the braking effect is the same on all the four/two wheels.

Instead of using brake fluids, hydraulic brakes are used to accelerate or stopping the vehicle. It is mostly used in all types of bikes and cars because of their effectiveness, the highest brake generating force capacity.

FAQs

1). What is Pascal’s law?

Blaise Pascal states that when the pressure applied to a fluid(confined incompressible fluid) in a system can transmit equal pressure in all directions throughout the fluid. This law was given by Blaise Pascal in 1647-48.

2). What is the formula for Pascal’s law?

The formula for pascal’s law is,

P = F/A

Where F= force, A = area, and P= pressure.

3). What is the function of braking systems?

A braking system is a mechanical device that helps in accelerating or decelerating the speed of the system. It inhibits motion by absorbing energy from the system.

4). Why the braking system is necessary for control systems?

The braking system is necessary in control systems to ensure the speed and time profile, stops the running systems in case of emergency, ensures system stability when not in use.

5). What are the types of brake assist systems?

The two types of brake assist systems are hydraulic brake assist system and mechanical braking assist system.

Thus, this is all about the braking – definition, types, mechanical braking, electrical braking, regenerative braking, plugging type braking, dynamic braking, and hydraulic braking systems. Here is a question for you, “What are disc-type and drum-type braking systems?”