Patent ID: 6881021
Filing Date: 2005-04-19
Classification: B66C

Abstract:
1. A telescopic boom mounted for pivoting about a horizontal pivot axis on a mounting bracket arranged on a vehicle, which comprises two box girders extending in a longitudinal direction in upwardly arched arcs of a circle and a first one of the box girders being guided in a second one of the box girders for displacement in the longitudinal direction, the upwardly arched arcs of a circle having a common axis extending parallel to the pivot axis, a servo-drive for displacing the box girders relative to each other, the first box girder having an end extending into an end of the second box girder and the servo-drive comprising two fluid-operated cylinders for displacing the box girders relative to each other, each cylinder having one end linked to an outer end of a respective one of the box girders and an opposite end linked to a common slider mounted displaceably in the end of the first box girder.