PURPOSE: To reduce the work manpower by driving a driven shaft in the direction of the shaft center by a driving member recovering the original form and reversing a reversing spring.

CONSTITUTION: A driven shaft 11 has a thin shaft part 17 nearly in its center part and a pair of collars 18a, 18b disposed in such a manner as to be opposite to each other with the thin shaft part between. Driving members 12, 13 are formed of shape memory resins having heater wires 19 integrated in the insides formed into J-shaped sectional forms, and shape-memorized in slightly opened states. The driving members 12, 13 also have through holes 20 capable of inserting the driven shaft 11 through, and terminals 21, 21 electrically connected to the heater wires 19 protruded from their lower end parts. Thus, the driving members 12, 13 of said pair formed of the shape memory materials alternately drive the driven shaft 11 in the shaft center direction when they recover the original shapes based on electric heating. Hence, the work manpower such as coil winding work can be reduced.