The best-selling speed reducer that provides high performance and high strength by using the original tooth structure Cyclo® Drives

By utilizing the unique circular tooth structure, the reduction gears are shock resistant and highly efficient, and can respond to a wide range of reduction gear ratios. Since the launch in 1939, it has been evolving to meet customer requests and gain their trust and support.


  1. 1Gear teeth that do not break

A curve plate is a component at the heart of a Cyclo® drive. Unlike involute gears, it features a unique smooth curvature (epitrochoid parallel curve). Furthermore, the unique circular teeth have also been adopted for the internal gears. A smooth rolling contact has been achieved with no damage to the teeth. Gaining a high reduction gear ratio with lower gears, in other words accomplishing both a high efficiency and a high reduction gear ratio, has been made possible.

Cyclo® drives feature a smooth rolling contact
Involute gears feature a sliding contact with smaller engagement ratios
  1. 2Perfect after sales service system

At the SHI Group, we believe it is our mission to ensure that our customers can use our reduction gears with long-term peace of mind. In order to make this possible, our service sites (about 40 locations) covering all of Japan respond to the need for repair and maintenance promptly and meticulously.

  1. 3Assortment of products

Take the direct motor drive type for example. Its capacity ranges between 0.1kW to 132kW and the reduction gear ratio has been standardized to between one-third to one-658503, with products delivered in a short time.Unlike ordinary gearmotors, the service factor (margin of reduction gears in relation to motor ratings) can be selected freely, even with identical capacities and identical reduction gear ratios. Furthermore, the most suitable unit for a particular purpose can be selected from an overwhelming assortment of products available, including the F series of products for precision controls that feature a built in torque limiter, motor pulley, servo motor direct drive, and robots, etc.

  1. 4International development

Various sites (production, assembly, hub, etc.) have been established in 50 countries around the world, including sales offices at 250 locations, in order to support the global business operations of our customers. Reliable sales and service activities are provided in Japan and around the world.

Sumitomo Drive Technologies deliver "Common global standards for quality and performance".

Product lines

For detailed information about the products please contact

Power Transmission & Control Group

Products for inquiries
Cyclo®Drives, Compact Gearmotors, Gearboxes, Motion Control Drives