| 摘要 |
PROBLEM TO BE SOLVED: To provide a case body manufactured so as to be recycled with a smaller number of components and at a low cost, making a color at the back of a through-hole inconspicuous while keeping strength, and providing a non-through hole for which the difference of appearance from the through-hole is eliminated together with excellent manufacture efficiency. SOLUTION: On at least one main surface of the case body 10, a plurality of fine through-holes having a cross sectional dimension smaller than the plate thickness dimension T of the main surface are disposed and a sound emitting hole area 11 is attained. The through-hole has two tapered parts composed of an outer side tapered part 11a (cross sectional dimensionϕd) and an inner side tapered part 11b (cross sectional dimensionϕd>ϕD) continued from the outer side 11d to the inner side 11e of the case body 10 so that the cross section of an intermediate part becomes narrowest. Near the sound emitting hole area 11, a pseudo sound emitting hole area where the plurality of non-through holes formed by recesses on the outer side of the case body 10 are disposed is provided. The non-through hole has a tapered part in which the cross sectional dimension on the bottom side of the recess is made smaller than the cross sectional dimension on the opening side of the recess. COPYRIGHT: (C)2006,JPO&NCIPI
|
