Himmelstein bearingless digital torquemeters offer an excellent solution for torque measurement applications where installation space is limited or high measurement accuracy is required.

As the name implies, the devices have no bearings, units consist of two components – a flanged style rotor/sensing element that is installed in the test shaft network and a stationary receiving antennae that is positioned nearby the rotor.

Himmelstein offers wide tolerance in positioning the stator relative to the rotor, typically ±10 mm axial and up to 8 mm radial. This greatly simplifies installation and limits the possibility of rotor to stator contact due to vibration or thermal expansion. No special alignment tools are required. Simply position the stator until all three LED’s show green, and the installation is complete.

Measurement technology is strain gage, with multiple bridges mounted on the rotor/sensing element.

Signal transfer is non-contact – inductive coupling of power to the rotating side which excites the bridges. On-board, rotating electronics processes the bridge output and digitizes the torque signal. A wireless digital signal transmission sends the torque data to the receiving stator. This stator then creates the available outputs of ±10 Vdc analog, a frequency modulated signal and digital over RS232/422/485.

Software is provided for torque data display and storage at a computer, as well as for making instrument settings.

Newly introduced models expand the available measurement ranges from 5 Nm to 2.5 MNm. They are available in three accuracy grades: standard ±0.04%, enhanced ±0.02% and ultra precision ±0.01% of full scale combined non-linearity and hysteresis. Also available are models with mechanical overload ratings of 200% and 400%, as well as dual range configurations. This permits optimal sizing of a sensor for a specific application yet still offers adequate protection from torque oscillations/spikes or startup torques.

Additional features include:

  • High overrange on all output signals. This prevents clipping of oscillatory torque peaks thus avoiding errors in the average torque measurement.
  • Extremely stiff torsional element design maximizes the installed bandwidth.
  • World-class temperature compensation including on board rotor side temperature measurement gives real time temperature change adjustment.
  • Low sensitivity to clamping loads.
  • Bi-directional rotor side shunt calibration.

These characteristics and more make the Himmelstein bearingless digital torquemeter the optimal choice for ease of setup and high accuracy torque measurement applications.