Multiple layer bypass hydrocarbon trap

Abstract

An air induction system for an engine includes an air filter box configured to receive an air filter that separates the air filter box into an atmosphere side and a filtered air side, a clean-air duct coupled downstream from the air filter box and upstream of the engine relative to a direction of air flow during engine operation, a flow-through hydrocarbon trap positioned within the clean-air duct, and a bypass hydrocarbon trap secured within the air filter box on the filtered air side, the hydrocarbon trap having a plurality of generally flat or coiled layers of hydrocarbon adsorbing material sandwiched together and secured one to another. Mechanical fasteners such as grommets may extend through the plurality of layers to secure the layers together. The fasteners may be secured to ribs extending along an upper surface of the air filter box or an interior surface of the clean-air duct.

Dependencies are inferred from the claim text.