| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a resin case having a synthetic resin cover vibration welded to one end of the main body of a tubular synthetic resin case having a rectangular transverse section in order to close the one end in which increase in the weight and production cost is prevented by ensuring a required strength of the cover with a minimum necessary material. <P>SOLUTION: Grid-like ribs 57 are projecting integrally from the rear surface of a cover 36 such that the arrangement density in the central part along the long and short sides of the cover 36 and at the opposite end parts thereof is higher than the arrangement density at other parts. <P>COPYRIGHT: (C)2004,JPO</p> |
