FZ - J (shaft coupling, base support) magnetic powder brake
Structure and working principle:
Magnetic powder brake is by the rotor, stator, including excitation winding magnetic yoke, relative concentric three parts assembly, can form a relative rotation of whole, in the annular space between the rotor and stator (cavity) filled with high magnetic conductivity alloy magnetic powder.
Excitation, and current through the coil, the working cavity of magnetic powder in loose state.Under the action of centrifugal force produced by the rotor and magnetic powder is evenly in the rotor on the inner wall of the weak interaction between rotor and stator, magnetic powder brake is in idle state, no torque output.
Field coil is energized, the yoke of magnetic flux, the magnetic powder in working cavity along the direction of the magnetic flux is chain link, magnetic powder brake is on the magnetic powder and magnetic powder, magnetic powder and working surface between friction and magnetic powder chain between the shear resistance to produce torque, magnetic powder brake in the loaded state.
Cut off the current, flux disappear, with the disappearance of the exciting current of magnetic powder under the action of gravity, in a loose state again, and under the action of centrifugal force, was dumped on the interior surface of the rotor, magnetic powder brake and is in a state of light. Features: The excitation current and torque is linear relationship.
When the excitation current is kept constant, the torque is not affected by the speed of the rotor, that is to say there was no difference in the static friction torque and friction torque, so can steadily implement torque constant.
This feature is applied to the dynamic test, the user just adjust the excitation current can accurately control the torque, so as to effectively control the size of the load resistance. Usually continuous sliding friction parts will be fever, and even burn out.But this equipment has the complete radiator, long time operation is not too hot, and long service life.