Patent ID: 6227523
Filing Date: 2001-05-08
Classification: E01F,E06B

Abstract:
Barrier comprising:a sunken trench having an upper perimeter at ground level and a lower level defining a base;two essentially vertical supports (1, 1') each of which having an upper end and a lower end, said lower end extending into said sunken trench (5),an upper essentially horizontal cross-beam (2) having a top side and a bottom side and having first and second ends guided in said vertical supports (1, 1') and moveable upwards to a raised position and downwards to an open position,a lower essentially horizontal cross-beam (3) having a top side and a bottom side and having first and second ends guided in said vertical supports (1, 1'), andtelescopic barrier elements (4; 4a, 4b, 4c) having first and second ends, which are connected at one end with the upper cross-beam (2) and at the other end with the lower cross-beam (3),wherein raising said upper cross-beam (2) causes said barrier elements (4; 4a, 4b, 4c) to be telescopically extended by the weight of the lower cross-beam (3), and wherein the lower cross-beam (3) remains in the sunken trench (5) when the upper cross-beam is in the raised position, andwherein lowering said upper cross-beam (3) to the open position causes said lower transverse support (3) to come into contact with said base (5a) of said sunken trench (5) and to telescopically constrict said barrier elements (4; 4a, 4b, 4c) in the sunken trench (5).