ELECTROMAGNETIC DRIVE UNIT AND HIGH PRESSURE PUMP USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an electromagnetic drive unit enabling suppression of erosion.SOLUTION: A movable core chamber 16 housing a movable core 14 of an electromagnetic drive unit 10 and a fluid chamber 44 in which fuel flows are partitioned by a partition part 17. The partition part 17 includes a communication hole 4 communicating the movable core chamber 16 and the fluid chamber 44 with each other. A cross section area of the communication hole 4 is equal to or larger than that of a core flow passage installed in the movable core chamber 16 in the moving direction of the movable core 14. Thus, a positive pressure vibratory force that is generated by a gap between the movable core 14 and a fixed core 13 when the movable core 14 is magnetically attracted to the fixed core 13 can reduce a negative pressure reflected wave reflected at an opening end on the fluid chamber side of the communication hole 4 or an opening end on the communication hole side of the core flow passage. Therefore, a volume percent of cavitation of the movable core chamber 16 can be reduced.