| 摘要 |
PURPOSE:To improve durability, by both communicating a plunger upper chamber to a diagonal groove through a communication hole provided in a plunger and vertically fuel suction control holes opened to the side of a cylinder. CONSTITUTION:In the above described pump in which a fuel feed amount is controlled by the rotary position of a diagonal groove 9 provided in the outside of a plunger 4, a plunger upper chamber 6 is communicated to the diagonal groove 9 by a communication hole 14. Further fuel suction control holes 5, 5' are vertically opened to the side of a cylinder 3, and a distance between centers of the holes 5, 5' are formed smaller than a distance between upper and lower edges of the diagonal groove 9 in its no-control position and larger than width of the maximum upper and lower edges in an injection control range by at least the hole diameter. Then a minimum distance between the lower edge of the diagonal groove 9 and the upper edge of the plunger 4 is arranged larger than the distance between the control holes 5, 5' by not less than the hole diameter. In this way, vertical motion of the plunger 4 can be smoothly performed. |
