to allow a horizontal displacement of the front hood 1 which is associated with pivoting of the front hood 1 about the axis which is formed in the hood lock and is denoted by 3 a it can be seen that the front hood 1 in the region of the hood part 8 mounted on it executes a displacement travel v the travel v is composed of a horizontal component x and a vertical component z which are likewise shown in fig3 it can therefore be seen that in the event of a collision with a pedestrian the front hood is lowered by the amount z and accordingly reduces its distance from the parts in the engine compartment which may be hard and therefore risk causing injury while at the same time the front hood 1 and therefore also the hood lock 3 are displaced by the amount x toward the rear as seen in the direction of travel if all four joints were designed to be stationary the translational movement could not be completed by the four joint hinge 4 since the four joints 9 to 12 only define one pivoting travel namely that which forms the basis for the opening movement of the front hood 1 and therefore the translational movement v would be statically overdetermined because the joint 9 is designed to change its position the static overdetermination of the four joint mechanism 4 is eliminated and the impact energy produced by the impact of a pedestrian on the front hood 1 is converted into the corresponding deformation energy and into further energy components which.