FITTING STRUCTURE FOR INSTRUMENT

摘要

PROBLEM TO BE SOLVED: To improve the safety of fitting work by screwing a screw to a ceiling and installing an engagement part engaged with the head of the screw to the main body of an instrument. SOLUTION: A casing 3 is formed of a base 3a in an almost disk shape and a sensor part 3b which is formed on the part and is in the almost disk shape. A recessed part 3c is formed at the base of the base part 3a. A pair of elastic engagement pieces in almost bow shapes, which grasp the head 1a of the engaged screw 1, are protrusively installed. When the casing 3 is fitted to a ceiling, the engaged screw 1 is screwed into a ceiling board 8 by screwing until a screw limit board 1c abuts on a ceiling face and it is fitted. The head 1a of the engaged screw 1 is engaged with a pair of elastic engaged pieces 2. Thus, the safety of fitting work can be improved.