Pilot valve controlled three-way fuel injection control valve assembly

摘要

A three-way fuel injection control valve assembly is provided which includes a pilot valve for controlling the movement of a drain valve member and a separate supply valve member to minimize valve response time and transition flow losses. The solenoid operated two-way pilot valve controls the flow of fuel from a control volume formed adjacent the ends of the drain valve member and the supply valve member to begin and end an injection event. A transition flow loss limiting feature is provided which causes the drain valve member to close prior to the opening of the supply valve member and subsequently causes the supply valve member to close prior to the opening of the drain valve member during a given injection event thereby minimizing transition flow losses. The transition flow loss limiting feature includes sizing the cross sectional areas of the supply valve member and the drain valve member, sizing a bias plunger for biasing the drain valve member and sizing one or more bias springs so that no opening overlap occurs between the supply valve member and the drain valve member.