| 摘要 |
PROBLEM TO BE SOLVED: To strongly and stably fit a bottom lid to a cylindrical main body in a three-piece case in which upper and bottom lids are fitted to the main body. SOLUTION: In this three-piece case, lock function parts are provided around both inner and outer peripheral surfaces at the lower end part of a main body 1, a bottom lid 20 is formed into double cylinder structure, and lock function parts are provided to be locked with both inner and outer lock function parts at the lower end part of the main body 1. The respective surface parts where the main body 1 including the lock function parts and bottom lid 20 are in press contact with each other are satin-finished, and by the locking of both the inner and outer lock function parts and the high frictional resistance of satin finished surface to be in press contact, the bottom lid 20 is strongly fitted to the main body 1. |
