Patent ID: 6108919
Filing Date: 2000-08-29
Classification: G01C

Abstract:
An automatic optical plumbing instrument for checking verticality of an object comprising:a telescopic housing;an objective telescopically mounted at a front portion of the telescopic housing adjacent to an object to be observed;an ocular telescopically mounted at a rear portion of the telescopic housing adjacent to an observer's eye for observig the image of the object through said ocular; anda transparent plumbing protractor having a plumbing line defined on said protractor and mounted in said telescopic housing in between said objective and said ocular for checking a verticality a vertical line of the object to be observed when said vertical line enters the telescopic housing to form an image of said vertical line as aligned with the plumbing line on said protractor; said transparent plumbing protractor including: a transparent circular casing mounted in the housing between the objective and the ocular, and located at a focus of the ocular; a transparent plumbing wheel rotatably mounted in the circular casing about a pivot fixed at the longitudinal centerline of the casing; a plumb weight secured at a lower portion of the plumbing wheel for pendulously rotating the wheel within the casing; a plumb-line mark diametrically formed on the plumbing wheel to align with a gravity center of the plumbing wheel loaded with the plumb weight thereon; a transparent liquid filled in the casing for damping the plumbing wheel as pendulously rotated within the casing about the pivot; and a plurality of angular graduations annularly formed on a periphery of the casing for indicating an angle of said vertical line of said object to be observed as deviated from said plumb-line mark or indicating an alignment of said vertical line with the plumb-line mark on the wheel.