RH Mini Series DC Servo Actuators from Harmonic Drive

High-powered RH Mini Series DC servo actuators from Harmonic Drive® were developed in order to control machinery and equipment smoothly, speedily and accurately.  A high level of positional accuracy and resolution, coupled with a compact and lightweight configuration, is the basis for the supermini RH Mini Series DC servo actuators.  These actuators can substantially reduce the time required for positioning.  At the heart of the performance of the RH Mini DC servo actuator is the Harmonic Drive strain wave gearing.

Harmonic RH Mini Series DC Servo Actuators
Harmonic RH Mini Series DC Servo Actuators

Harmonic Drive strain wave gearing is known for zero backlash, high torque, compact size, and excellent positional accuracy.   Features include:

Excellent Positional Accuracy and Repeatability – Positional accuracy may be minimized within one arc minute and repeatability within a few seconds.

High Torque Capacity – Since power is transmitted through multiple tooth engagement, the gear offers high output torque capacity equal to drives twice its size and three times its weight.

Zero Backlash – Cup-type gear only versions operate with zero backlash between mating teeth because of natural gear preload and radial tooth movement.  The only shaft-to-shaft backlash that exists, originates in the input coupling (oldham coupling) and ranges from 2-36 arc-sec depending on unit size and reduction ratio.  This coupling can be eliminated if necessary, resulting in zero backlash for the entire drive.

In – Line Configuration – The gearing input and output shafts are concentric, allowing machine designers to dramatically reduce the required packaging space compared to other high ratio, high torque drives.

High Torsional Stiffness – The new “S” tooth profile greatly improves the torsional stiffness of the gear allowing greater precision and higher servo gains.

Efficiencies – Operating efficiencies of up to 90% can be obtained.  Ratings are based on actual shaft-to-shaft tests.

Back Driving – Harmonic Drive gear is reversible and can be back driven.  If necessary, loads can be held in place by braking the Wave Generator when the servo system is not powered.

More information on the RH Mini Series DC Servo Actuators and Zero Backlash Gearing Products from Harmonic Drive can be viewed at-


For more information, please contact:

Warren Osak
Toll Free Phone:   877-737-8698
Toll Free Fax:       877-737-8699

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