Diesel Engine Emissions: A Tinning Control Approach

Growing demands are being placed on the diesel engine industry to lower emission levels. A key ingredient in emissions reduction is precise injection pump to engine timing control. This paper outlines a unique approach to dynamically time an injection pump to an engine during its initial test cycle while developing the ability to repeat the timing function using the same methodology during the life of the engine.

This innovative concept consists of the placement of a piezoelectric sensor in the high pressure tubing path at the injector inlet. Coupled with a device which employs microwave sensing of relative piston position, exact dynamic timing can be accomplished. The sensor output not only provides the initial timing reference, but also a consistent reference for the engine's diagnostic needs. The output can also be used as a tach drive or provide input to an electronically controlled injection system.