| 摘要 |
PURPOSE:To decrease an amount of air bubbles generated in fuel due to a negative pressure, by a method wherein the edge on the delivery port side of a suction port opened to the inner peripheral surface of a cylinder is positioned further rearwardly than the maximum advance position of the tip surface of a plunger contained forward and backward movably in a cylinder. CONSTITUTION:When an engine is started and rotation of a crank wheel 6 is transmitted to a drive shaft 5, a plunger 11 is moved forward and backward through a cam mechanism formed with a roller 17 and a disc cam 13. Along with backward movement of the plunger 11, a pressure in a cylinder 12 is reduced. In this case, a suction port 22 is released before the plunger 11 is moved backward to an intermediate position between a maximum advance position and a maximum reversing position, and fuel is sucked in the cylinder 11 through the working of a valve device 24. Meanwhile, along with forward movement of the plunger 11, a pressure in the cylinder 12 is increased, and fuel is delivered through the delivery port of a delivery valve device 31. This constitution causes suction of fuel before a negative pressure in the cylinder 12 is reduced to a low value, and suppresses the generation of air bubbles in fuel. |
