01-04-2011, 02:18 PM
Presented by:
KSHITIJ K. WEER.
GAYNOR GRATION LEWIS .
SANKET S. TAVSALKAR.
SANJEEV A. BAWASKAR.
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ELECTRO - MAGNETIC BRAKES
: SUMMARY :
Now days, the lot’s of new technologies are arriving in world. They create a lot of effect. Most of industries got their new faces due to this arrival of technologies. Automobile industry is also one of them. There is a boom in world’s automobile industry, so lot’s of research is also going here. As an important part of automobile, there are also innovations in brakes. Electromagnetic brakes is one of them.
Electromagnetic brakes is a new revolutionary concept. Electromagnetic brakes are the brakes working on electric power & magnetic power. They works on the principle of electromagnetism. These are totally frictionless. Due to this, they are more durable & have longer life span. Less maintenance is there. These brakes are an excellent replacement on the conventional brakes due to their many advantages. The reason for implementing this brake in automobiles is to reduce wear in brakes as it is frictionless. Therefore there will also be no heat loss. It can be used in heavy vehicles as well as in light vehicles. The electromagnetic brakes are much effective than conventional brakes & the time taken for application of brakes are also smaller. There is very few need of lubrication. Electromagnetic brakes gives better performance with less cost which is today’s need. There are also many more advantages of Electromagnetic brakes. That’s why Electromagnetic brakes are an excellent replacement on conventional brakes. Electromagnetic brakes are the need of today’s automobiles.
A electromagnetic braking system for automobiles like cars, an effective braking system. And, by using this electro magnetic brakes, we can increases the life of the braking unit. The working principle of this system is that when the magnetic flux passes through and perpendicular to the rotating wheel the eddy current is induced in the rotating wheel or rotor. This eddy current flows opposite to the rotating wheel/rotor direction. This eddy current trying to stop the rotating wheel or rotor. This results in the rotating wheel or rotor comes to rest/ neutral.
Construction :
The construction of the electromagnetic braking system is very simple. The parts needed for the construction are electro magnets, rheostat, sensors and magnetic insulator. A cylindrical ring shaped electro magnet with winding is placed parallel to rotating wheel disc/ rotor. The electro magnet is fixed, like as stator and coils are wounded along the electromagnet. These coils are connected with electrical circuit containing one rheostat which is connected with brake pedal. And the rheostat is used to control the electric current flowing in the coils which are wounded on the electro magnet and a magnetic insulator is used to focus and control the magnetic flux. And also it is used to prevent the magnetisation of other parts like axle and it act as a support frame for the electromagnet. The sensors used to indicate the disconnection in the whole circuit. If there is any error it gives an alert, so we can avoid accident.
Working principle : At the initial stage the brake pedal and rheostat are in rest. When we apply the brake through the brake pedal, the rheostat allows the current to flow through the circuit and this current energise the electromagnet. The amount of current flow is controlled by the rheostat. Depending on the current flow different amount of magnetic flux can be obtained. By this varying magnetic flux, different mode of brakes can be obtained. For example, if we want to suddenly stop the vehicle then press the brake pedal fully, then the rheostat allows maximum current which is enough to stop the vehicle. Similarly we can reduce the speed of the vehicle by applying the brake gradually.
: INTRODUCTION :
Currently the automobile safety norms are going strict & strict which is important for saving occupant’s life in case of emergency. Brakes are one of the safety systems in automobiles. These days, many types of brakes are in use. Let’s first see what are brakes.
Brake :
Brake is a device which inhibits motion or stops motion. They are the essential & important part of safety system of automobile. The primary functions of brakes are as follows.
1. To stop the vehicle in minimum possible distance.
2. To park the vehicle on slops.
For these purposes, brakes are used. Many developments are made in design of brakes. The brakes are classified as,
• According to purpose :
1) Primary or service brake.
2) Secondary or Parking brakes.
• According to construction :
1) Drum Brake.
2) Disc Brake.
• According to method of actuation :
1) Mechanical brake.
2) Hydraulic brake.
3) Air brake.
4) Electric brake.
5) Vacuum brake.
Brakes are generally applied to rotating axles or wheels. Some vehicles use a combination of braking mechanisms, such as drag racing cars with both wheel brakes and a parachute, or airplanes with both wheel brakes and drag flaps raised into the air during landing. Let us see some commonly used brakes in automobiles.
