TUNNEL CEILING SURFACE MARKING METHOD AND APPARATUS

PROBLEM TO BE SOLVED: To provide a method for positioning a ceiling top section and an installation position, by applying laser light and discharging marking from an arbitrary position at the bottom section, in which the equipment to be installed on the ceiling is to be installed. SOLUTION: A tunnel ceiling surface marking apparatus comprises a laser irradiating section 16 for irradiating a ceiling surface 50 with laser beams, from an arbitrary position at the bottom of a tunnel; a PC controller 22 for measuring irradiation distance and an angle at the irradiation point of laser beams, calculating ceiling height, and sets the maximum value of the ceiling height as the ceiling top section; an angle-changing section 12 for irradiating the ceiling top section with laser beams for fixation; and a marker-discharge section 14 that is formed in one piece in the same direction as the laser irradiation section 16 and discharges a bullet for marking to an irradiation point, thus measuring the ceiling top section from an arbitrary position at the bottom of the tunnel for marking. In this case, a plurality of installation positions separated from the ceiling top section are measured, on the basis of the ceiling top section for marking. COPYRIGHT: (C)2006,JPO&NCIPI