| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power tool capable of improving a heat radiating property of a switching element even in using a plurality of the switching elements. <P>SOLUTION: This power tool has an electric circuit substrate 52 on which the switching element 44 is mounted, a metal case 50 in which the electric circuit substrate 52 and the switching element 44 are stored and an insulating filler R filled in the inside of the metal case 50 in a melting state and to bury a clearance between an internal wall surface of the metal case 50 and the electric circuit substrate 52 and the switching element 44, the switching element 44 is constituted of a charging part 44k and an insulating covering material to cover a semiconductor chip, the charging part 44k makes face-contact with the electric circuit substrate 52, and the covering material makes face-contact with the internal wall surface 50b of the metal case 50. <P>COPYRIGHT: (C)2009,JPO&INPIT |
