Energy management system and method for an extruded aluminum vehicle subframe

This invention relates to an energy management system and method for absorbing and directing kinetic energy during an impact event of a motor vehicle. More particularly, the present invention relates to a deformable aluminum attachment bracket for attaching an extruded vehicle subframe to a vehicle chassis, where the attachment bracket is purposely deformed upon experiencing an impact load above a predetermined level, allowing the subframe to drop down and below the vehicle chassis during an impact event. An energy management system and method for absorbing and directing kinetic energy during an impact event of a motor vehicle includes a vehicle subframe attached to a vehicle chassis , with a pair of deformable attachment brackets and interposed therebetween. The deformable attachment brackets and are preferably fixedly attached to the subframe and removably attached to the vehicle chassis via fasteners extending through a fastener hole in each of the attachment brackets and . A relief opening is proximate to and aligned with the fastener hole , the relief opening being larger than the fastener . A deformable barrier disposed between the fastener hole and relief opening may be provided with a slot extending between the fastener hole and relief opening . Upon an impact generating an impact force above a predetermined force, the fastener deforms the deformable barrier , whereby the deformable attachment bracket and is displaced longitudinally such that the fastener is relocated from the fastener hole into the relief opening . The fastener slides out of the relief opening and the subframe drops beneath the vehicle chassis , whereby the subframe translates longitudinally relative the vehicle chassis during the crash event, safely away from the vehicle occupant compartment.