Device for enlarging effective withdrawal length of telescoping jib for mobile crane or lift work platform, has rod and main power cylinder pivotally connected to jib at their tips that are movable along identical arcs

摘要

A rod (1) and a main power cylinder (3) are pivotally connected at the base ends to a turntable (15) and at the tips to a telescoping jib (7). The rod and the cylinder rotate the jib to a working or raised position (11) as such that their tips move along identical arcs. The base end of the power cylinder is also movable along a similar arc. To make the arcs identical with each other, the distances between the base ends of both rod and cylinder in the raised position is identical to the virtual rod length (2) from the tip of the rod to the base end of the cylinder in the lowered position. The gap between the base ends of the cylinder at the lowered and raised positions is identical to the actual length of the rod.