ELECTRIC LINEAR ACTUATOR

PROBLEM TO BE SOLVED: To provide an electric linear actuator in which noise caused from a gear reduction mechanism is suppressed, its assembling work is simplified and a cost is reduced.SOLUTION: In an electric linear actuator provided with a nut 14 which is supported so as to be rotatable via a pair of supporting bearings 15, 16 installed at a housing 2 and so as not to be movable in an axial direction and in the inner periphery of which a helical thread groove 14a is formed, a tolerance ring 17 is insert-fitted to a fitting surface between an output gear 5 and the nut 14 with a fastening margin not to allow slipping even when maximum torque is applied. The tolerance ring 17 is formed into a semicircular shape such that a circle is divided into two by press working of a steel plate. These two tolerance rings are combined to form a nearly annular shape, a plurality of waveform portions 18 are protruded outward in a radial direction at equal intervals along a peripheral direction, and at the same time, these waveform portions 18 are constituted of annular parts 18a and protruded parts 18b each of which is formed between the annular parts 18a.