The Heidenhain ERN 420 is an incremental rotary encoder with integral bearing and stator-mounted coupling.
The stator coupling allows for even tilt and can reliably compensate for axial play. The hollow shaft of this
encoder is slid directly onto and fastened to the shaft to be measured with no additional rotor coupling
required. During angular acceleration of the shaft, the stator coupling must absorb only that torque resulting
from friction in the bearing, providing excellent dynamic performance and a high natural frequency.
The ERN 400 series are available with various interfaces, allowing them to be connected directly to most subsequent electronics without the need for an adapter or a signal converter. Possible applications range from simple measuring tasks to position and speed control on servo drives.