Ford has patented an interesting method for capturing hydrocarbon (HC) pollutants from a car engine. In the newly developed Ford technology, an engine air intake duct includes a molded-in hydrocarbon vapor trap.
In a typical installation in current use, a HC trap is located downstream from an air filter box and upstream from intake runners feeding into the cylinders of the engine. A trap includes an HC-adsorbing element from one or more sheets of paper or plastic impregnated with activated carbon. This attracts vapors when the engine is shut down. When the engine restarts, fresh air pushes the vapors into the engine where they are burned.
In the new approach, an insert is first formed by attaching a hydrocarbon-adsorbing element to a frame. The insert is then positioned with a blow-molding core, which is enveloped by a plastic parison. The insert is exposed to a hollow interior of the shell.