Patent ID: 6167631
Filing Date: 2001-01-02
Classification: G01C

Abstract:
A plummet level comprising a long hexahedral main body having a predetermined proper length, and two extensible links connected to two ends of said main body; said main body defining an internal space that is divided into front and rear halves; said front half having a first central pivot shaft provided therein for supporting a beam having a predetermined proper length, such that said beam always maintains in a horizontal and balanced state, a reference lever line being provided at a front surface of said beam along a full length of a central line of said beam, a first long clear window being provided on a wall of said main body facing said beam, said first long clear window having an overall length substantially equal to that of said beam and a plurality of spaced and parallel check lines extending a full length of said first long clear window; and said rear half having a second central pivot shaft provided therein for supporting a swing link having a predetermined proper length, said swing link having a plummet connected to one end thereof so that said swing link is always in a vertical position with said end having said plummet always pointing downward when said plummet level is in a vertical position, said swing link also having a reference vertical line provided at its front surface along a full length of its central line, a second long clear window being provided on a wall of said main body facing said swing link, said second long clear window having an overall length substantially equal to that of said swing link and a plurality of spaced and parallel check lines extending a full length of said second long clear window; and said extensible links each including an end plate and two guide bars, said end plate each has four inward and perpendicularly extended corners that each defines a right angle, said four right-angled corners of each said end plate being respectively in alignment with four side walls of said main body, said guide bars being slidably received in dovetail slots axially provided inside said main body, so that said extensible links may be pulled or pushed relative to said main body; whereby a user may use said plummet level to check a working surface for its horizontal or vertical state by visually overlapping one of said check lines and said reference level line or said reference vertical line, and when a working surface that has a length or height exceeded said length of said main body, said extensible links may be selectively pulled out to facilitate convenient measuring of said working surface.