| 摘要 |
PURPOSE:To obtain an injection system without generating secondary injection and cavity by a method wherein a jerk type fuel pump is provided with a non- return valve, formed with a predetermined choking, at the delivery part thereof while another non-return valve is provided at the vicinity of an oil reservoir in an oil path in a fuel valve. CONSTITUTION:When a cam 2 is rotated to begin lifting, a plunger 4 is elevated to close an oil feeding and discharging port 15. As a result, fuel, pressurized to a high pressure, opens a delivery non-return valve 102 and the non-return valve 202 of the fuel valve forcibly and is introduced into the oil reservoir 26 through the oil path 22 in the fuel valve. Then, a needle valve 25 is opened against a spring 28 and the fuel is injected out of a nozzle 30. On the other hand, when the cam 2 is rotated further and the lift thereof becomes large to communicate a plunger chamber 17 with an oil feeding chamber 16, the pressure of the plunger chamber 17 is reduced and discharge is finished. At this time, the non-return valve 202 is closed to prevent generation of the secondary injection. The delivery non-return valve 102 is also closed at this moment, however, the cavity will never be generated in a fuel injection pipe 19 by the effect of a choke valve 103. |
