The working principle and use of magnetic powder brake controller

The working principle of magnetic powder brake and how to use it

1. Working principle

Magnetic powder brakes and magnetic powder clutches are based on electromagnetic principles and use magnetic powder to transmit torque. It has a linear relationship between the excitation current and the transmitted torque. It can transmit a certain torque irrespective of slip and has the advantages of fast response speed, simple structure, no pollution, no noise, no shock vibration, and energy saving. It is a multi-purpose automatic control element with superior performance. Magnetic powder brakes are widely used in various mechanical braking for different purposes, power test loading, unwinding tension control, etc. Magnetic powder clutches are widely used in buffer starting, overload protection, speed regulation, tension control of winding in winding systems, etc.

2. Basic Features

a. Exciting current-torque characteristics

The excitation current and the torque are basically in a linear relationship, and the magnitude of the torque is controlled by adjusting the excitation current.

b. Speed-torque characteristics

The torque has nothing to do with the speed and keeps a constant value. (When the excitation current is constant, the torque is not affected by the speed change within the allowable slip speed range) There is no difference between static torque and dynamic torque.

c. The allowable slip power of the magnetic powder brake is a fixed value when the heat dissipation conditions are constant. When it is actually selected and selected, the practical slip power needs to be within the allowable slip power. When the operating speed is high, the torque needs to be reduced.

3. How to use

Magnetic powder brakes and clutches use direct current as excitation power. Our company produces SJ-180A electronic, manual, and automatic tension controllers as its special control power supplies.

During the transportation process of magnetic powder brake and magnetic powder clutch, magnetic powder is often used to gather in a certain place, and sometimes even "stuck" phenomenon occurs. At this point, just turn the whole brake or clutch 180 degrees and hit it with a wooden hammer a few times to loosen the magnetic powder. Or use a lever to turn the shaft left and right, as long as it is turned. It is recommended to choose a clearance fit for the connection fit of the coupling. Axial knocking is strictly prohibited. Run-in operation should be carried out before use. First, run through the rated current of about 20% for a few seconds, then power off and then power on again, and repeat several times. Brakes above 500N.m. Some magnetic powders are installed separately. During the run-in, the magnetic powder can be injected from the top magnetic powder filling port, and the magnetic powder can be gradually injected while rotating without the excitation current.