| 摘要 |
<P>PROBLEM TO BE SOLVED: To efficiently release to outside the heat emitted from resistances necessary for lighting up light-emitting elements and preclude deterioration of other base board components, softening and deformation of resin components forming push-button switches. <P>SOLUTION: Heat emitted from the resistances 7 is taken in by an obverse side heat radiation pattern 3 formed on the surface of a printed wiring board 2 and released to the outside air, and using a plurality of through holes 5 the heat is passed through a path following the obverse side heat radiation pattern 3 and the reverse side heat radiation pattern 4 so as to attain also the reverse side heat radiation pattern 4 having a wide radiation area formed on the reverse side of the printed wiring board 2 and then is released to the outside air. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
