Michael M. Schechter

Using Camless Valvetrain for Air Hybrid Optimization

The air-hybrid engine absorbs the vehicle kinetic energy during braking, puts it into storage in the form of compressed air, and reuses it to assist in subsequent vehicle acceleration. In contrast to electric hybrid, the air hybrid does not require a second propulsion system. This approach provides a significant improvement in fuel economy without the electric hybrid complexity. The paper explores the fuel economy potential of an air hybrid engine by presenting the modeling results of a 2.5L V6 spark-ignition engine equipped with an electrohydraulic camless valvetrain and used in a 4531 kg passenger car. It describes the engine modifications, thermodynamics of various operating modes and vehicle driving cycle simulation. The air hybrid modeling projected a 64% and 12% of fuel economy improvement over the baseline vehicle in city and highway driving respectively. This is possible without reducing the vehicle weight to compensate for additional hardware and without reducing engine displacement.

EMI-series ― Electromagnetic fuel injection pumps

Usage of solenoid valves capable of controlling fuel delivery to several engine cylinders in succession reduces the cost and complexity of electromagnetic fuel injection systems. A new type of injection pump employing solenoid valves with shuttles is described. In a multiplunger pump such a solenoid valve controls operation of two plungers in succession. The number of required solenoids is equal to half the number of engine cylinders