CEILING DIRECT MOUNT TYPE LUMINAIRE

摘要

PROBLEM TO BE SOLVED: To reduce the possibility of falling of an apparatus body accompanied with the linear movement (horizontal slippage) or rotation of the apparatus body. SOLUTION: This luminaire has an adaptor 10 having an adaptor body 11 fixed to a ceiling surface; a male screw part 13 suspended from the center thereof and having a male thread 12 on the circumference; and a female screw part 16 having a female thread 15 to be attachably and detachably screwed to the male screw part 13. It also has an apparatus body 20. The apparatus body 20 comprises a backbone 21 exposed to the ceiling surface side. A double circular hole 22 comprising a major hole part 22L having a size loosely insertable of the female screw part 16 and a small hole part 22S having a size loosely insertable of the male screw part 13 is formed on the backbone 21. The peripheral part of the small hole part 22S in the backbone 21 is fastened by the female screw part 16. A projection 23 is formed on the peripheral part of the small hole part 22S in the backbone 21. A receiving hole part 14 to be attachably and detachably engaged with the projection 23 is formed in the circumferential position of the male screw part 13 in the adaptor body 11. The projection 23 is engaged with the receiving hole part 14 to prevent the rotation of the backbone 21 around the male screw part 12 and also prevent the linear movement along the longitudinal direction of the double circular hole 22.