Patent ID: 6755180
Filing Date: 2004-06-29
Classification: F02D,F02M

Abstract:
A distribution type fuel injection pump includinga pump chamber, a feed pump that feeds fuel to the pump chamber, a timer apparatus that advances and retards fuel injection timing according to increase and decrease of fuel pressure in the pump chamber, and a governor having a fly weight, a governor shaft, a governor sleeve whose inner surface is slidably fitted to an outer circumference of the governor shaft, and a fluid passage formed in the governor shaft and the governor sleeve, through which communication between a suction side of the pump and the pump chamber is allowed or interrupted according to back and forth axial movement of the governor sleeve relative to the governor shaft based on closing and opening of the fly weight, the fluid passage comprising: an inside way-out including a first shaft port axially extending in a center of the governor shaft, one end of the first shaft port communicating with the suction side of the pump and the other end of the first shaft port being sealed, an annular groove formed on the outer circumference of the governor shaft to face the inner surface of the governor sleeve, and a second shaft port extending in a radial direction of the governor shaft from the first shaft port to a bottom of the annular groove, a corner of the second shaft port opening to the bottom of the annular groove being provided with one of a chamfering portion formed by cutting off flatly the corner and a rounding portion formed by rounding the corner; and an outside way-out whose one end opens to the inner surface of the governor sleeve to face the outer circumference of the governor shaft and whose the other end opens to an outer surface of the governor sleeve to communicate with the pump chamber, wherein, according to the back and forth axial movement of the governor sleeve, the fuel pressure in the pump chamber increases when the communication between the inside and outside way-outs is shut off and decreases when the inside and outside way-outs communicate with each other.