Abstract: Aiming at medical apparatus and instruments such as endoscope, a kind of wireless thermal expansion microactuator is designed, it is actuated by thermal expansion of paraffin, which is heated by a thermoseed heated by magnetic induction. Experimental studies on thermal-expansion of paraffin and induction heating are conducted. The results show that paraffin has a large coefficient of expansion in temperature range near its melting point, the paraffin used in the experiment has a melting point ranging from 37 to 39 , and its volume expansion coefficient can reach 15%, induction heating has a high heating speed. Based on these experimental studies, six microactuator models are constructed, and the characteristics of their displacement output are tested. The results show that the displacement output of paraffin thermal expansion microactuator is very large.

Key words: Induction heating, Micromechanism Actuator Paraffin