LOW ARM ATTACHING STRUCTURE IN HYDROFORM TYPE SUBFRAME

摘要

A low arm mounting structure of a hydroforming sub frame is provided to avoid interference with other devices by forming a cut unit at the sub frame and to occupy a small working space for installing a stiffener and a nut unit by welding the stiffener and the nut unit directly to a cut unit cover. A low arm mounting structure of a hydroforming sub frame(1) is composed of the tube-shaped sub frame having a closed curve and a cut unit(2) formed at which a low arm is installed; a cut unit cover(5) fixed along the cut unit to cover and close the cut unit and formed with mounting holes(7) at both sides; a reinforcing unit(10) separated from the inside of the cut unit cover at a predetermined gap in the cut unit cover and formed with guide holes(11) facing the mounting holes; and a nut unit(15) of which a middle region passes through the guide holes in the cut unit cover, one end is contacted to the mounting hole, and an inner diametral surface has a female screw(16). The nut unit is combined with a fixing bolt(19) having a male screw through the female screw. The cut unit is cut concavely from the outside of the sub frame to the inside. The cut unit cover is fixed to the sub frame by welding and the reinforcing unit is installed to the cut unit cover by welding.