Lift arm arrangement of a construction machine

摘要

Conventional lift arm arrangements for construction machines include a pair of lift arms that are welded fabrications forming box-beams. The lift arms are typically connected by a cross tube that is welded to the inner walls of each lift arm. This type of construction creates an extremely heavy arrangement that requires several very labor intensive welding operations to manufacture. The present invention provides a lift arm arrangement that includes lift arms that are made of one-piece, cast members. Each lift arm includes an integral abutment portion that defines a surface that is adapted for welding to a cross tube assembly. The surface is configured to be spaced laterally from the inner side surfaces of each lift arm. Being so positioned, the stress concentrations created by the welded joint are moved to a location that is removed from the juncture between the cross tube assembly and the side surfaces of the lift arms.