JPS63198434U

JPS63198434U -

Info

Publication number: JPS63198434U
Application number: JP9028187U
Authority: JP
Priority date: 1987-06-13
Filing date: 1987-06-13
Publication date: 1988-12-21

Description

[Brief explanation of the drawing]

第１図は本考案の一実施例の構成を示す断面図
、第２図は第１図の―断面図、第３図は同上
実施例に使用する第１の調圧弁の開度特性図、第
４図は同上実施例の第２の調圧弁の開度特性図、
第５図は同上実施例のポンプ室の燃料圧力の特性
図、第６図は同上実施例の燃料噴射時期特性図、
第７図は従来の分配型燃料噴射ポンプの断面図、
第８図は第７図の―断面図である。３……ポンプハウジング、５……プランジヤ、
８……カムデイスク、９ａ……ローラ、９……ロ
ーラホルダ、１０……ピン、１２……タイマーピ
ストン、２３……燃料戻し通路、２４……第１の
調圧弁、２５……ポンプ室、２６……燃料戻し弁
、２７……第２の調圧弁。 FIG. 1 is a cross-sectional view showing the configuration of an embodiment of the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. 3 is an opening characteristic diagram of a first pressure regulating valve used in the same embodiment. FIG. 4 is an opening characteristic diagram of the second pressure regulating valve of the same embodiment as above;
FIG. 5 is a characteristic diagram of the fuel pressure in the pump chamber of the same embodiment, and FIG. 6 is a fuel injection timing characteristic diagram of the same embodiment.
Figure 7 is a cross-sectional view of a conventional distribution type fuel injection pump.
FIG. 8 is a cross-sectional view of FIG. 7. 3...Pump housing, 5...Plunger,
8... Cam disc, 9a... Roller, 9... Roller holder, 10... Pin, 12... Timer piston, 23... Fuel return passage, 24... First pressure regulating valve, 25... Pump chamber, 26... Fuel return valve, 27... Second pressure regulating valve.

Claims

[Scope of utility model registration request]

A feed pump that is driven by an engine and discharges fuel into a pump chamber in a pump housing, a plunger that is rotationally driven in synchronization with the rotation of the engine, a cam disk formed on the plunger, and a cam disk that is freely rotatable around the same axis as the plunger. a cam follower member disposed and engaged with the cam disc and causing the plunger to reciprocate in the axial direction to forcefully feed and inject fuel to a fuel injection valve mounted on the engine; A distribution type fuel injection pump comprising a timer piston that controls fuel injection timing due to reciprocating motion of a plunger by adjusting the rotational position of a cam follower member according to the fuel pressure in the pump chamber, wherein a discharge port of the feed pump and a low pressure The first valve is installed in the fuel return passage connecting to the fuel source, and has the characteristic that the degree of opening increases as the fuel pressure increases and becomes fully open at a predetermined fuel pressure or higher.
The first pressure regulating valve is interposed in the fuel return passage connecting the pump chamber and the low pressure source, and the degree of opening increases as the fuel pressure increases above the fuel pressure that is higher than the fuel pressure that fully opens the first pressure regulating valve. What is claimed is: 1. An injection timing control device for a distribution type fuel injection pump, comprising: a second pressure regulating valve having a characteristic of