Magnetic particle clutches and magnetic particle brakes

magnetic powder clutches -brakes

performance size from 0,2 Nm up to 1000 Nm

The magnetic particle clutch respectively brake achieves at a low driving power a high torque being independent of slip speed. It distinguishes itself by a simple structure, low weight and requires little room.

This advantage makes it possible for the clutch resp. brake to be employed in the solution of many technical problems. Appropriate regulation and control devices - as for ex. our LIEDTKE Controller - are needed for the different applications.


  • unwinding brakes/winding
  • torque controls
  • torque limitations
  • speed controls
  • clutch proceedings
  • start controls

The characteristics of the magnetic particle clutches and brakes are a great advantage in control engineering. By changing the intensity of the exciting current, the torque to be transferred can be adjusted within the range of about 1:50.
Characteristic Charts Magnetic powder clutches and brakes
  1. The torque to be transferred and the exciting current behave to each other just proportionally.
  2. In case of a fixed exciting current the torque is independent from the differential speed of the two rotors.
  3. When starting, the torque builds up itself  time delayed. DC sided switching results in shorter switching times than switching on the mains side.
  4. The switching times for the clutches and brakes can be improved when put ting in series an active resistance with the exciting coil.

Magnetic particle clutches are available with solid shaft and without slip ring transmitter for a range from 0,2 to 5 Nm (Type EFAS) applicable as clutch or brake.
The models with hollow shaft and slip ring transmitters are available for the range from 2 to 1000 Nm, with or without heat sink (Type ERA or Type EAT) depending on how much power is lost by customer application.


EAT 20

EAT 2002
Click on pic will grow the view


ERAT 120-650

ERAT 5001

Magnetic particle brakes are available with solid shaft for a range from 0,2 to 5 Nm (Type FAS).
The models with hollow shaft are available for a range from 2 to 1000 Nm, with or without heat sink (Type FAT or Type FRAT) or with water cooling (Type FRATO) depending on how much power is lost by customer application.

FAS 50

FAT 20

FAT 2002


FRAT 120-650

FRAT 5001

FRATO 2002

FRATO 5001

The standard types are destined for horizontal shaft mounting only.

If vertical shaft mounting is required or if rotation speed <= 40 min-1 is desired, types with remanent rotor (app. "RR") must be installed.
This variant is available in nearly all sizes.
In this version the amount of rest torque is nearly two times as high as in the standard models.

Brakes with heat sink in nearly all sizes can be fitted with external fans.

FRAT 120-650 with fan

FRAT 2002 with fan

For more product information, click here.

LIEDTKE Antriebstechnik GmbH & Co. KG

LIEDTKE Magnetpulverkupplungen und -bremsen GmbH & Co. KG

Böcklerstraße 1
D- 31789 Hameln
Phone: +49 (0) 51 51 / 98 89 -0