To simulate a wide variety of real-world conditions on automotive components and systems, test stands often need brakes that can deliver a range of torque levels while minimizing cost and control complexity. That’s where magnetic particle brakes come into play.
Particle brakes adjust transmission torque based on controlled variations of a magnetic field generated by an electromagnetic coil. Unlike other types of brakes, particle brakes don’t rely on friction plates or electromechanical components to adjust torque. Instead, the magnetic field directly acts upon a metallic powder that fills the air gap between the brake’s primary and secondary rotors. The powder’s “viscosity” changes with applied current, creating controllable drag forces between the rotors for a continuously adjustable transmission torque. When the secondary rotor is fixed to the equipment frame, the device acts as a brake. Otherwise, it acts as a clutch.
Electromagnetic Actuation Yields Accurate, Reproducible Torque
Magnetic particle brakes need a small DC current to provide a wide operating torque range to simulate the stresses that automotive components must endure. Particle brake technology offers several advantages:
- Reliable, reproducible torque load that is proportional to the applied current.
- Fast response. The magnetic particles react quickly to the DC power.
- A compact, fully electric solution.
- Low power consumption — 1.5A can generate 1,000 Nm of torque.
- Torque that is completely independent of speed variations.
Merobel™ Magnetic Particle Brakes are available in a wide range of types and sizes to simulate various system load cycles. Depending on the size, test bench designers can simulate a variety of torque from 0.007 to 1,000 Nm. The fully electric brake solution provides reliable, reproducible torque via a low-power analog signal and can simulate many kinds of graphs and torque curves.
With Merobel’s digital controller and brakes, differences in measured torque values from set point values are quickly corrected, and the available Modbus TCP/IP communication allows for easy control and monitoring.
The brakes can accommodate various test bench types such as those for product development or endurance testing. And depending on the precision required, they can even comprise the core element of test benches. Merobel Magnetic Particle Brakes and electronic control products offer:
- Fast response times — as low as 50 milliseconds.
- Digital controllers with built-in amplifier and power supply for closed loop control with real-time feedback.
- Compact design.
- Little to no maintenance required.
- High rated power dissipation — up to 12 KW.
- Software included.
- Customers can create documents for proof-of-test.
- Powered by standard control voltage of 24 VDC/AC.
Taken together, designers can achieve precise, variable and easy-to-control torque loads in a simple, compact system. Redex USA can help test bench designers find the right Merobel Magnetic Particle Brakes and components for their application, provide technical support and evaluate any heat dissipation needs.
For more information about Merobel Magnetic Particle Brakes, visit the product page.