PURPOSE: To facilitate the attachment/detachment of a water supply rotation mechanism by installing an attachable/detachable pipe which can be disengaged from a main water supply pipe by turning operation in a space between the main water supply pipe and a rotary pipe and disassembling the rotary pipe from the main water supply pipe with the attachable/detachable pipe.

CONSTITUTION: In order to operate a sprinkler A, a pressurized water in a water supply pipe C installed under the ground is acted to a main water supply pipe 6 and the folded part of a nozzle pipe 8 to expose a nozzle 10 on the ground by lifting the main water supply pipe 6 by the water pressure. The pressurized water is ejected from the nozzle 10, and the direction of water is turned by a given angle through a water hitting tool 26. By rotating a rotary pipe 7 within an attachable/detachable pipe M, a nozzle pipe 8 linked to the rotary pipe 7 is rotated integrally. At the time of inspection for maintenance, after a lid 31 being removed from a casing 1, the attachable/detachable pipe M which is engaged with the nozzle pipe 8 by an engagement mechanism G is lifted by turning manually by a specific angle to detach from the main water supply pipe.