PURPOSE:To make a converter into a microminiaturized size by a method wherein a conductive linear shape memory material to memorize a shpae is coated with an elastic coating material to be supplied with power recovering the memorizing capacity. CONSTITUTION:The linear shape memory material 1 comprising Ti-Ni alloy etc. is formed of arm 3 comprising coil element 5 and linear elements 6, 7 and forked holding unit 4 while the entire surface of the material 1 is coated with the coating material 2 with less thermal conductivity such as soft and elastic silicon rubber etc. Then firstly both the state of closed holding unit 4 and the state of bent arm unit 3 are memorized by means of said shape memory material 1 and said holding unit 4 is closed by means of connecting power supply 10 to said holding unit 4 while said arm 3 is bent by means of connecting said power supply 10 to said arm unit 3. Through these procedures,electric energy may be converted into dynamic energy by means of supplying said units 3 and 4 with power to simlify the constitution making the converter ultra compact.