Patent ID: 8128721

Claim:
A filter device for an internal combustion engine of a motor vehicle, said filter device comprising: an unfiltered air intake area, a flexible elongated filter element comprised of a filter hose of a filter medium, said filter hose having a filter wall separating an unfiltered side from a clean side of the filter device in a radial direction, wherein the filter wall of the filter hose is provided with a very fine particle filtration layer comprised of nanofibers, wherein said filter element is flexible in at least one of an axial and a radial direction, a filtered air duct, wherein the unfiltered air intake area is disposed on the underside of the engine hood of the vehicle and is attached to the engine hood, wherein the filter hose comprises a tubular body mounted to and moving with the engine hood, the filter medium having a porosity such that adequate filtering of the intake air for the internal combustion engine is ensured, wherein the tubular body has a pleated geometry that facilitates a curved installation, wherein the tubular body is arranged on an underside of the engine hood within a substantially airtight cover, said a cover having an intake air passage open toward the front of the vehicle and toward the front of the engine hood to draw in air into said unfiltered side of said filter hose, wherein at least one intake air passage is provided in which said filter hose is arranged, said intake air passage extending directly under the engine hood inside side cover and opening into a common plenum chamber delivering air to said engine, and wherein between an outer wall of said filter hose and an inner wall of the said cover an annular space is provided for a flow of a fluid to be filtered.