Abstract: A torque limiter means for controlling rotary motion is disclosed, comprising a casing, a shaft rotatively mounted in the casing, a pulley fixedly secured to the shaft and a coaxial rotor also secured to the shaft. The rotor has an odd number of radial cam projections which engage a pair of pins, these latter oscillating in transverse back and forth movement. A transversely oriented follower plate is rigidly secured to the pins and consequently also oscillates in back and forth movement thereby producing a braking action on the shaft.