Counterweight removal system and method

Abstract

Mobile cranes have a jib mounted on a platform or deck of a road vehicle so that the crane can be transported from one working site to another. Such a crane may have a counterweight on the rear of the crane jib superstructure and mounted so that it can be moved inwardly and outwardly relative the superstructure to balance the load on the jib. When the crane is to be driven along the rod, however, the jib is folded over the platform of the vehicle and in addition the counterweight is desirably removed from the jib superstructure and carried in a position on the vehicle platform where its weight best suits the vehicle suspension. In order to remove the counterweight, the superstructure is slewed to bring the counterweight to a position adjacent an upwardly inclined surface carried by the platform of the vehicle, the bottom surface of the counterweight being inclined at a corresponding angle to the horizontal equal to that of the inclined surface. The counterweight is then moved to engage the underside of the counterweight with the inclined surface on the platform and cause the counterweight to "ride up" the inclined surface of the block. In this position, the load on the beams carrying the counterweight is removed so that the counterweight can be removed and tied to the vehicle platform for travel. In this way, the hydraulic rams or the like which control the balancing movements of the counterweight can be used in the disengagement and re-engagement of the counterweight and no extra hydraulic rams are needed.

Dependencies are inferred from the claim text.