Low Weight and Low Inertia Make for Energy-Saving Torque Couplings for Shafts

Feb. 1, 2011
Low weight and low inertia make for energy-saving torque couplings for shaft
Request free information via our Reader Service Web site at

Engineers at R+W America, Bensenville, Ill. (, have redesigned the SL Series of torque limiters so that they have less mass and inertia, which translates into energy savings, higher throughput rates, less downtime, and consistent performance.

The Series relies on a proven spring-loaded detent subsystem and a previously patented preload for zero backlash. And coupling weight has also been painstakingly reduced by 50%. For example, a conventional torque limiter rated to disengage at 160 Nm typically has a mass of 1.3 kg and a 1.6 × 10-3 kgm2 moment of inertia. The SL version’s mass is 370 gm and its moment of inertia is 0.8 × 10-3 kgm2.

The company cut weight by redesigning the springs and making components smaller. The four sizes of couplings in the Series have torque settings ranging from 5 to 700 Nm, bore diameters from 0.5 to 2.250 in., and include rigid flange, bellows couplings, and elastomer coupling configurations. They operate in temperatures from –22 to 248°F, and handle over 10,000 disengagements, depending on rotational speed. The SLN clamping and SLP keyway (shown) use flanges to attach to sprockets, sheaves, pulleys, and gears, and have dual bearings to support belt and chain tension. The SL2 bellows coupling and SLE servo insert coupling mount in-line between independently supported shafts. All limiters are field adjustable and come with English and metric bores.

© 2011 Penton Media, Inc.

Sponsored Recommendations

The entire spectrum of drive technology

June 5, 2024
Read exciting stories about all aspects of maxon drive technology in our magazine.


May 15, 2024
Production equipment is expensive and needs to be protected against input abnormalities such as voltage, current, frequency, and phase to stay online and in operation for the ...

Solenoid Valve Mechanics: Understanding Force Balance Equations

May 13, 2024
When evaluating a solenoid valve for a particular application, it is important to ensure that the valve can both remain in state and transition between its de-energized and fully...

Solenoid Valve Basics: What They Are, What They Do, and How They Work

May 13, 2024
A solenoid valve is an electromechanical device used to control the flow of a liquid or gas. It is comprised of two features: a solenoid and a valve. The solenoid is an electric...

Voice your opinion!

To join the conversation, and become an exclusive member of Machine Design, create an account today!