JPS6418011A - Plumbing apparatus - Google Patents

Abstract

PURPOSE:To obtain an apparatus of convenient use with a simple construction using laser, by arranging a cylinder body provided with a convex lens at the upper end thereof to make a specified expanse of laser beam parallel and with a bob weight at the lower end thereof to be supported centered on the focus of an optical system in such a manner so as to oscillate freely. CONSTITUTION:A mirror head 9 having a convex lens 8 at the upper end thereof is provided with a bob weight 10 at the lower end thereof and supported with a support mechanism 11 centered on the focus A of an optical system comprising a concave lens 5 and the lens 8 in such a manner as to oscillate freely. When a main body 1 is horizontal, a laser beam B radiated from a laser 2 is reflected with mirrors 3 and 4 and incident into the lens 5 from below passing through the focus A to diffuse at a specified angle of expanse. Then, the beam is made parallel with the lens 8 to be radiated upward vertically. The center line of the beam B coincides with the optical axis of the optical system. Then, when the body 1 is inclined by an angle delta, the center line of the beam B passes at the point A while the cylinder body 6 fixed on the main body 1 holding the lens 5 tilts by an angle delta on the point A. Then, the beam is incident into the lens 8 as shifted by the angle delta while being corrected in the vertical direction by refraction to be radiated.