23-08-2013, 04:56 PM
Electromagnetic Disc Brake
Electromagnetic Disc .pptx (Size: 294.06 KB / Downloads: 213)
Introduction
Electromagnetic disk braking system so as to have a future alternative to traditional breaking systems. Electromagnetic disk braking system slows an objects by creating an eddy current through electromagnetic induction which create resistance.
Electromagnetic brakes (also called electro-mechanical brakes or EM brakes) slow or stop motion using electromagnetic force to apply mechanical resistance (friction). The original name was "electro-mechanical brakes" but over the years the name changed to "electromagnetic brakes", referring to their actuation method.
Since becoming popular in the mid-20th century especially in trains and trolleys, the variety of applications and brake designs has increased dramatically, but the basic operation remains the same.
Working Principle
The basic law which apply on this braking system is Lenz Law and Eddy Current phenomena helps in braking.
A simple disc about to be stopped quickly by eddy currents As the disc enters the magnetic field a series of eddy currents will be produced (as explained by Lenz’s law). This produces a magnetic field that will oppose the change brought about by the rotating disc. If the magnetic field of the horseshoe magnet is coming out of the page then the induced magnetic field will be into the page.
The induced current will be in a clockwise direction to produce this field. This will bring the disc to a halt very quickly and will result in a small amount of heat being produced by the eddy currents.
Construction Steps
We take 4 electromagnetic coil and test then with providing power supply.
Now we take one metallic dice and arrange electromagnets .
We rotate to the dice manually and then we give power supply to electromagnets then we see sudden braking applied.
Now we plane to make our project fully automated with control with footpad as we can use in commercial market. First we take one plastic tyre and fix it on wooden frame with help of bearing and metal shaft
We provide rotation to the tyre with help of motor with connecting chain and sprocket.
Applications
In locomotives, a mechanical linkage transmits torque to an electromagnetic braking component.
Trams and trains use electromagnetic track brakes where the braking element is pressed by magnetic force to the rail. They are distinguished from mechanical track brakes, where the braking element is mechanically pressed on the rail.
Electric motors in industrial and robotic applications also employ electromagnetic brakes.
Recent design innovations have led to the application of electromagnetic brakes to aircraft applications. In this application, a combination motor/generator is used first as a motor to spin the tires up to speed prior to touchdown, thus reducing wear on the tires, and then as a generator to provide regenerative braking.