CEILING INSPECTION HOLE

摘要

PROBLEM TO BE SOLVED: To facilitate installation to the opening section of a ceiling board while smoothing the open-close operation of an internal frame body between a closing place where the opening section of an external frame body is closed and an open place where the opening section of the external frame body is slid on the rear side of the ceiling board and opened. SOLUTION: A housing frame body 60 with a pair of housing frame bodies 61 extended from the upper sections of the mutually opposed external frame materials 33 of the external frame body towards the rear side of the ceiling board 1 and a connecting frame material 62 framing sections in the vicinity of the extended end sections of these housing frame bodies 61 at regular intervals is formed integrally to the external frame materials 33. Guide rails 70 are mounted extending over a pair of the housing frame materials 61 from the mutually opposed external frame materials 33 while sliding bodies 130 moved and guided along the guide rails 70 are secured to the internal frame body 100. Accordingly, the internal frame body 100 is constituted in a sliding openable-closeable manner at the closing place where the internal frame body 100 is closed in the opening section of the external frame body 31 and a place where the body 100 is housed in the housing frame body 60.