Multifunction false floor element comprising foam pads acting as springs of a " mass-spring " system

The floor pan unit has a rigid body (2) made up of plastic material. A flexible foam body (3) covers an external face of a lower zone of a hollow block (5) and air conduit (8) in the rigid body. A carpet (4) is placed against the foam body disposed on an upper face of the rigid body. A threaded shaft pushes a foot rest that is separated from the rigid body, when shock causes deformation of a pad connected to foot rest. Independent claims are also included for the following: (A) a floor pan of a passenger compartment of a motor vehicle (B) a method of manufacturing a false floor pan unit.