weight without distortion of the structural rectangle into a parallelogram in fig1 and 7 spring 27 serves a double purpose first it biases ratchet member 8 into engagement with the teeth on ring 9 and second it provides a restoring force for resetting the system to its initial position as the vehicle rebounds from the collision the reset displacement of arms 7 is cushioned by rubber stops 28 attached to bracket 14 since the bumper beam is supported by vertical pivot bolts 6 and 3 on radius arms 7 and links 2 respectively bumper beam 1 could be free to move laterally on these pivots if no restraints were provided centrifugal forces in a turn or during lane changing could displace the bumper laterally to the end of its travel without such restraints the required bumper lateral positioning system must accurately center the bumper with respect to the vehicle frame and allow no lateral bumper displacements for all possible centrifugal forces at the same time when such forces are exceeded in a collision situation the bumper centering system must allow the bumper to be deflected laterally for impacts occurring at an angle with respect to the vehicle longitudinal axis the resulting bumper displacement then fig5 has a longitudinal component 34.