Abstract: A torque limiting overload coupling for preventing an excessive load given to an output element from being reversely transferred to an input element which includes a plurality of paired balls, used as a rotation-transmitting connection between the input and output elements and which are held by the same number of holes extending through a ring plate fastened to the input element, held between a flange on the input element and a slider movable in the axial direction and slidably held on the input element. Each pair of balls has one ball engaged in a hole of the flange and the other ball engaged in a hole of the slider which is biased towards the flange by a compressive force of a spring attached to the rear side of the slider. In a space between the slider and the input element are a pair of parallel, trapezoidal cross-sectioned bars which form a tapered groove therebetween in which an intervener is received, the intervener formed from many sections of a ring having a wedge shaped cross-section.