| 摘要 |
<P>PROBLEM TO BE SOLVED: To further reduce generation of cavitation erosion by optimizing a shape of a suction and overflow hole of a plunger barrel of a fuel injection pump. <P>SOLUTION: This fuel injection pump 1 is constituted so as to control inlet-outlet of fuel to at least one suction and overflow hole 8 formed in a pump plunger bush 3 by an upper side control edge part 11 and a lower side control edge part 12 of a pump plunger 4 reciprocating in the pump plunger bush 3, and forms an early control groove 10 in a wall part of the suction and overflow hole 8. The suction and overflow hole 8 is composed of a small diameter hole 81 having an opening surface 14 for peeping at the inside of the pump plunger bush 3 on one end 81A and a large diameter hole 82 communicating with the other end 81B of the small diameter hole 81. A bottom part 10A of the early control groove 10 extends by inclining upward in the direction for separating from the opening surface 14. A space for avoiding a direct hit by a fuel jet is formed in a connecting end part of the large diameter hole 82 with the small diameter hole 81. <P>COPYRIGHT: (C)2007,JPO&INPIT |
