Patent ID: 6175484
Filing Date: 2001-01-16
Classification: F02D

Abstract:
An apparatus for recovering solenoid coil energy in a solenoid driver circuit comprising:a first solenoid driver circuit including a solenoid coil for controlling the operation of an actuator; a high voltage capacitor coupled to said solenoid coil for providing current flow thereto; a high voltage select switch connecting said capacitor to said solenoid coil; a low voltage supply coupled to said solenoid coil; a select switch connecting said low voltage supply to said solenoid coil; a flyback current path connecting said solenoid coil with said high voltage capacitor; and an electronic controller coupled to said high voltage select switch and to said select switch and being operable to output control signals thereto;a second solenoid driver circuit including a solenoid coil for controlling the operation of an actuator; and a high voltage capacitor coupled to said solenoid coil for providing current flow thereto and a flyback current path connecting said solenoid coil with said high voltage capacitor; andthe high voltage capacitor of said first driver circuit being connected in parallel to the high voltage capacitor of said second driver circuit;wherein the current generated by the back EMF of the solenoid coil associated with said second driver circuit is operable to charge the high voltage capacitor of said first driver circuit at a time when the high voltage capacitor of said first driver circuit is providing current flow through the solenoid coil of said first driver circuit.