Based on a compact and simple design, the ESL series torque limiters from R+W offer accurate performance at a reasonable cost. Unlike traditional ball-detent torque limiters, the ESL spring loads two series of ball bearings against one another to create a rolling effect at overload.
The rolling effect reduces wear and at the same time lets the clutching interface serve as the bearing support during overload disengagements, saving space and cost. This torque limiter uses a specially developed “digressive spring characteristic,” so sensitivity to overload and torque disengagement accuracy are not compromised. Disengagement takes place within 3 milliseconds of overload, and at a value within +/-5% of the disengagement torque setting. The basic design mounts with a keyway and set screw; customized mounting attachments are also available. Technical specifications, solid models, and video are available at:
R+W America
http://www.rw-america.com/elastomer_couplings/torque-limiting-coupling-esL-t.php