| 摘要 |
PURPOSE:To prevent an operating member from being heated by arranging heat generating electric parts at one end in a longitudinal direction of a case and arranging the operating member at the other end beyond the center in a longitudinal direction of the case. CONSTITUTION:A circuit board 14 has a noise canceler coil 17 and a semiconductor switching element 18, which are high heat generating electric parts, arranged at the uppermost portion. An operator 34 is placed at the lower side of the center in a longitudinal direction of a case 11. In this way, a long distance is secured for directly heat transfer from the noise canceler coil 17 and the semiconductor switching element 18 to the operator 34 in order reduce heat transfer to the operating member 41. It is thus possible to keep the operating member 41 from temperature rise to a minimum. |
