What is a Hysteresis Brake?
A hysteresis brake is a type of electromagnetic brake that utilizes the principle of hysteresis to transmit torque. Hysteresis, in this context, refers to the ability of a magnetic material to retain some of its magnetic properties even after the magnetizing force is removed. The brake consists of two parts: the rotor, which is usually made of a high-permeability magnetic material, and the stator, which is an electromagnet that can be turned on or off. When the stator is energized, a magnetic field is created, which induces eddy currents in the rotor. These eddy currents cause the rotor to heat up, dissipating mechanical energy and creating a braking effect.
How does a Hysteresis Brake Work?
The operation of a hysteresis brake is relatively simple. When the input shaft, which is connected to the rotor, turns, it induces eddy currents in the rotor. These eddy currents create a magnetic field that opposes the magnetic field of the stator, causing the rotor to slow down. The amount of torque generated by the brake is proportional to the difference between the magnetic fields of the rotor and the stator. The brake can be controlled by varying the strength of the stator’s magnetic field, which will affect the amount of torque generated by the brake.
Applications of Hysteresis Brakes
Hysteresis brakes are used in a variety of applications where precise torque control is required. They are commonly used in industrial machinery, such as printing presses, wire drawing machines, and textile machines. They are also used in automotive applications, such as transmission dynos and brake dynamometers. In addition, hysteresis brakes are used in laboratory and scientific applications where precise torque control is necessary, such as in rheometers and viscometers.
Example of Hysteresis Brake Technology
One example of hysteresis brake technology is the Magtrol Hysteresis Brake. The brake consists of a stationary stator and a rotating rotor, which is made of a high-permeability magnetic material. The stator is wound with a coil of wire, which creates a magnetic field when energized. As the rotor turns, eddy currents are induced in the rotor, creating a magnetic field that opposes the magnetic field of the stator, which creates a braking effect. The Magtrol Hysteresis Brake is used in a variety of applications, including torque calibration and testing of motors and other machinery.
