HarmonicDrive Rotary Actuators RSF supermini /RSF-B / RSF / RKF Series

HarmonicDrive Rotary Actuators RSF supermini /RSF-B / RSF / RKF Series



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Email:  info@aurotek.com

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Email:  info@aurotek.com

HarmonicDrive Rotary Actuators

HarmonicDrive RSF supermini /RSF-B / RSF / RKF Series
HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列 HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列 HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列 HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列
HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列
HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列
HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列
HarmonicDrive 旋轉型致動器 RSF supermini /RSF-B / RSF / RKF 系列

Excellent Technology Clusters in a Wide Range of Industries

HarmonicDrive® products are unique wave motion gearings that play important roles in robots,
semiconductor manufacturing systems, factory automation equipment...
as well as in aerospace equipment that foster the dreams of humanity.
We offer a variety of mechanical electronic products that bring about high precision motion
control in optical measuring equipment, medical equipment, printing machines and other systems.
Our products offer many advantages in the fields of industrial and scientific technology.
Harmonic Drive Systems Inc. is making every effort to develop supportive technologies for the
21st century, thereby contributing to the advancement of global technology.


High rotational and positioning accuracy, compact and light weight, high reduction ratio, high torque capacity,
non-backlash, high efficiency, silent operation


Driven by a unique operating principle applying metal elastodynamics and comprising only three basic parts (a wave generator, flexspline and a circular
spline), our HarmonicDrive wave motion gearing (registered trademark) excel with superb characteristics that are not found in other wave motion gearing


HarmonicDrive® Structure of HarmonicDrive® Unit (Component Type)


The Flexspline is a non-rigid, thin cylindrical cup with external teeth, with a slightly smaller pitch diameter than the Circular Spline. The bottom of the Flexspline is called the diaphragm, and is usually mounted onto the output shaft.

Wave Generator

The Wave Generator is a thin raced ball bearing fitted onto an elliptical hub serving as a high
efficiency torque converter, and is generally mounted onto the input shaft.

Circular Spline

The Circular Spline is a rigid ring with internal teeth of the same size as the Flexspline, but the
Circular Spline has two more teeth than the Flexspline and is generally mounted onto the housing.

Operating Principle 

There are three main components. The Flexspline is bent into an elliptical shape by the Wave Generator; and the teeth of the
long axis of the ellipse engage with the Circular Spline, whereas the teeth of the short axis are completely separated.
As the Circular Spline is fixed in place and Wave Generator (input) rotates in a clockwise direction, the Flexspline deforms elastically and the position where the gears mesh with the Circular Spline moves in turn. For each rotation of the Wave Generator, the Flexspline rotates backwards by only two teeth from its original position, or in other words in the reverse direction relative to the Wave Generator. This motion is generally retrieved as the output.


Tooth behavior and engagement

Unlike the motion of ordinary gears, the unique tooth behavior (operating principle) of the
HarmonicDrive® makes non-backlash motion possible, as well as infinitesimal angular feeding
(one-pulse feeding) and high positioning accuracy. More than 30% of all teeth simultaneously
engage in two locations in 180° symmetry, allowing for high torque capability.

RSF supermini Series

AC Servo Motors/Super Compact Cylinder Type

The RSF-5B is a compact and high-torque AC servo actuator series with a high rotational accuracy, combining a HarmonicDrive® speed reducer for precision control and an AC servo motor. An actuator with brake is part of the standard lineup. Combined with a dedicated AC servo driver HA-680 for DC 24V power supply, which fully demonstrates the performance of this AC servo actuator, these products make compact machines and equipment with a high rotational accuracy
a reality.

RSF/RKF Series

AC Servo Motors/Compact Cylinder Type

The AC servo actuators in the RSF·RKF series are comprised of a HarmonicDrive® component for precise motion control and
an AC servo motor, featuring high torque and high rotational accuracy in a compact design.
The RSF·RKF series AC servo actuators are best suited as positioning drives for machines and systems that require a more compact design.


RSF-B mini Series

AC Servo Motors/Compact Cylinder Type

The RSF-B mini series features an integrated HarmonicDrive® component for precision control and is considerably high in
output torque in relation to the external dimensions with a high torque, compared to the direct driving method for a single
high capacity motor.
Also, this series allows smaller and more lightweight products with a dedicated AC servo motor.