Patent ID: 6384420
Filing Date: 2002-05-07
Classification: G01C

Abstract:
A portable gravity-based self-levelling device for outwardly projecting a laser ray or a flat beam of laser rays (L, L11, L12, L110, L120) in a horizontal and/or vertical direction even if the device lies in an inclined position, said device comprising: a case (C) in the form of a hollow housing (1) provided with resting members (3); a pendulum (11) suspended inside the case (C) by suspension means (5, 9), said pendulum comprising a mass or weight (16) at its bottom; means (23A, 23B, 24) for damping the pendulum swing; means (18, 19) for adjusting the equilibrium position of the pendulum (11); and, mounted on the pendulum (11), means (12), operable from the outside and powered by at least one battery (21) contained in the case (C), for projecting collimated visible laser rays, and able, when the pendulum (11) is in its rest position, to outwardly project a horizontal collimated laser ray or at least one horizontal and/or vertical flat beam of laser rays wherein the suspension means comprise at least one first mechanical decoupling member such as a ball or roller bearing (5), associated with the hollow housing (1), and a second mechanical decoupling member such as a ball or roller bearing (9), associated by way of a first part (9B) thereof with a movable part (6) of said first decoupling member (5), a second part (9A) of said second member supporting the pendulum (11), the two members or bearings (5, 9) lying in mutually perpendicular planes.