Unlike a regular involute tooth-gear, the "cycloidal disc," which is the gear for the Cyclo® Reducer, features a distinctively smooth curve.
A unique circular-arc tooth profile is also used for the internal gear. The smooth rolling contact that prevents tooth breakage results in a durable reducer with a long service life. (Some low reduction ratio models use helical gears and planetary gears.)
Cyclo® Drive for Servo Motors
Reducer featuring high strength and reliability, thanks to its unique Cyclo® mechanism
- Our Cyclo® reducer with a flange, for servo motors.
- Utilizes our unique Cyclo® mechanism for durability and long product life.
Two Series:
- Standard-Backlash Series
- Low-Backlash Series: 6 arc min (12 arc min for reduction ratio 6)
- Standard-Backlash Series
Allowable Peak Torque | 29.7 - 1370 N⋅m |
Motor Capacity | 0.2 kW - 9.0 kW |
Output Shaft Direction(s) | Any Mounting Direction (horizontal, vertical downward, vertical upward) |
Mounting Style | Foot Mount, Case mount, Flange Mount |
Frame Size | 12 sizes |
Reduction Ratio | 6:1 - 87:1 |
- Low-Backlash Series
Backlash | 6 arc min(12 arc min for reduction ratio 6) |
Allowable Peak Torque | 29.7 - 630 N⋅m |
Motor Capacity | 0.2 kW - 5.0 kW |
Output Shaft Direction(s) | Any Mounting Direction |
Mounting Style | Foot Mount, Case mount, Flange Mount |
Frame Size | 4 sizes |
Reduction Ratio | 6:1 - 29:1 |
Product Features
Leverages the Cyclo® Mechanism
Uses the Cyclo® mechanism with our "cycloidal disc"
Durable and Long-Life
Cyclo® mechanism features smooth rolling contact that prevents tooth breakage and results in a durable reducer with a long service life.
Any Mounting Direction
Reducer supports the following mounting methods: Foot Mounting, Case Mounting, and Flange Mounting.
Compatible with 2 Motor Shafts
Compatible with keyless or keyed motor shafts.
Easy Motor Mounting
The adapter is compatible with servo motors from all manufacturers. You are able to easily assemble it yourself.

Break-Resistant Teeth
We offer almost any desired option, from a motor adapter to an assembly that includes the motor and is ready for mounting right out of the box. Contact your Sumitomo representative for more details.
The Servo 100, Servo 6000, and Fine Cyclo reducers can withstand momentary shock loads as high as 500% of the rated torque.
Emergency 24h Contact
1-416-565-4264In case of after hours service emergency, please contact the number above.

Looking for a different product?
Click on our Product Selector to quickly find the right product from our entire lineup. Our intuitive filters help you find the product that best suits your application.