| 摘要 |
PROBLEM TO BE SOLVED: To provide an opening/closing device that prevents an arm from being detached from a casing during normal use, and allows the arm to be detached from the casing when a predetermined force or greater is applied in an opening direction.SOLUTION: A lid 30 is attached to the housing 20 with an opening 21 formed therein. The lid 30 turns in the direction of opening and closing the opening 21 around one end. An arm 40 is extended from the body 31 of the lid 30. An engagement part 41 is formed at the tip end of the arm 40. The engagement part 41 has a first contact face 44 and a second contact face 45. In the periphery of the engagement part 41, a narrow part 47 is formed which is made partially narrow. The arm 40 is inserted into an arm hole 23. In the position where the lid 30 is opened to the maximum, the engagement part 41 is engaged with the peripheral part of the arm hole 23. When a predetermined force or greater is applied in the direction in which the lid 30 is opened, the narrow part 47 is deformed and engagement between the engagement part 41 and the peripheral part of the arm hole 23 is released. |
