JPS633416Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a fuel injection device for an internal combustion engine.

In the known device shown in FIG. 1, the fuel injection amount is adjusted by rotating a sleeve 101 with an injection amount adjustment rod 100 and further rotating a plunger 102, while moving a control sleeve 103 in the axial direction of the plunger. In particular, adjust the injection timing. As described above, since the injection amount adjustment system and the injection timing adjustment system are separate, the structure of the pump becomes complicated. Further, the injection amount is adjusted by rotating the plunger 102, but in such a type, a large force is required to rotate the plunger 102 when pressure is applied to the plunger chamber 104.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks by making it possible to adjust the injection amount and injection timing of the control sleeve by controlling the movement of one adjustment rod.

The present invention will be explained below based on illustrated embodiments.

In FIG. 2, the plunger 1 has an axial hole 8 connecting the plunger chamber 9 and the fuel suction chamber 10.
and a radial hole 8a, and a width across flats 11 is provided so that the plunger 1 does not rotate.
(See Figure 3). Furthermore, the plunger 1 is tightly fitted with the cylinders 6, 7 and the control sleeve 2. Cylinder 6 is bolt 13
and is tightened to the housing 24 by a nut 14, pressing the cylinder 7 downward with the fuel spill shielding portion 6a. The control sleeve 2 is rotatable and movable up and down relative to the plunger 1, and has a lead 3a for regulating the start of injection and a lead 3b for regulating the end of injection, and has a hole 16 into which the sleeve adjustment pin 15 is tightly fitted. have As shown in FIG. 4, the hole 16 is formed by fixing the block 17 with a bolt 18 so that it is tightly fitted even when the sleeve adjustment pin 15 moves in a direction perpendicular to the axial direction of the plunger 1. It's summery. The intermediate sleeve 25 having the sleeve adjustment pin 15 has a position adjustment hole 19, and a rod 26 is inserted into the hole 20 of the adjustment rod 4 and the hole 19 to adjust the position of the adjustment rod 4 and the intermediate sleeve 25. Afterwards, both 4 and 25 are fixed with screws 21.

Next, the operation will be explained. When the tappet 22 is raised against the plunger spring 5 by a cam (not shown), the plunger 1 is raised, and when the radial hole 8a of the plunger 1 is closed by the control sleeve 2 as shown in FIG. Plunger chamber 9
The fuel is pressurized, pushes up the valve 23, and is directed to a nozzle, not shown. When the plunger 1 further rises and the radial hole 8a touches the end-of-injection lead 3b of the control sleeve 2 as shown in FIG. is released into the suction chamber 10,
Fuel pumping ends.

To adjust the fuel injection amount, move the adjustment rod 4 to the plunger 1.
By moving the control sleeve 2 in a direction perpendicular to the axial direction of the control sleeve 2, the relative position between the radial hole 8a of the plunger 1 and the injection end regulation lead 3b of the control sleeve 2 is changed, and the fuel pumping stroke is changed. Do it by doing this.

On the other hand, to adjust the injection timing, the control sleeve 2 is moved up and down by rotating the adjustment rod 4, and the injection start regulation lead 3a of the control sleeve 2 is adjusted.
This is done by changing the timing at which the plunger closes the radial hole 8a.

In addition, when adjusting the injection timing according to the load, the control sleeve 2 is adjusted so that the injection timing as well as the injection amount can be changed by rotating the control sleeve 2.
The injection start regulation lead 3a may be tilted.

Furthermore, the width across flats of the lower seat 12 may be provided on the tapepet 22 instead of being provided on the lower seat. In short, it is sufficient that the plunger 1 cannot be rotated and that the tappet 22 and the plunger 1 can be fixed. Therefore, for example, as shown in FIG. 7, screws may be used.

Furthermore, the connection between the intermediate sleeve 25 and the control sleeve 2 may be such that the movement of the adjustment rod 4 is transmitted to the control sleeve 2 without play; for example, as shown in FIGS.
Two adjustment pins 1 in the intermediate sleeve 25 as shown.
5a, 15b may be provided and engaged with the respective grooves 16a, 16b of the sleeve 2.

Furthermore, the control sleeve 2 may be provided with an adjustment pin 15, and the intermediate sleeve 25 may be provided with a hole in which the pin is engaged. Further, the hole 16 may be a square hole or a round hole.

As described above, the present invention effectively utilizes the rotation and axial movement of one adjustment rod that is engaged with the control sleeve, and moves the adjustment rod in a direction perpendicular to the axial direction of the plunger. By rotating the control sleeve, the fuel injection amount is adjusted, and by moving the adjustment rod in the axial direction of the plunger, the control sleeve is moved up and down to adjust the fuel injection timing, so one adjustment is required. As a result of being able to adjust both the fuel injection amount and fuel injection timing using the rod, the structure of the pump can be greatly simplified and the pump can be made smaller and lighter, which is an extremely excellent practical effect. As a result, the space for the plunger spring can be increased, making it possible to use a spring with a large spring force, thereby suppressing the jumping of the tappet and allowing the pump to rotate at high speed. Furthermore, the force required to rotate the control sleeve is smaller than that required to rotate a conventional plunger, and the responsiveness is improved, making it easier to prevent hunting.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional structure, FIG. 2 is a sectional view showing an embodiment of the present invention, FIG. 3 is a perspective sectional view of the lower seat 12 shown in FIG. BB cross-sectional view of the control sleeve 2, FIGS. 5 and 6
7 is a sectional view of the main part showing another embodiment, FIG. 8 is a perspective view of the main part showing still another embodiment, and FIG. 9 is A of FIG. 8. It is an arrow view. 1...Plunger, 2...Control sleeve, 3a
... Lead for regulating the start of injection, 3b... Lead for regulating the end of injection, 4... Adjustment rod, 8... Axial hole, 8
a... Radial hole, 9... Plunger chamber, 10...
...Fuel intake chamber.

Claims (1)

[Scope of utility model registration request] A plunger chamber is provided at the tip of the reciprocating plunger, and the plunger chamber can communicate with the fuel suction chamber through an axial hole and a radial hole in the plunger, and the radial hole is opened and closed by a control sleeve inserted into the plunger. In a device that controls fuel injection timing by displacement of a control sleeve in the axial direction of a plunger, the control sleeve is rotatable relative to the plunger, and the control sleeve has an injection start regulation lead and an injection end regulation lead. by changing the distance between the two along the circumferential direction of the control sleeve, and using the rotation and axial movement of one adjustment rod engaged with the control sleeve, the adjustment rod is aligned with the axis of the plunger. By moving the control sleeve in a direction perpendicular to the direction, the control sleeve is rotated to adjust the fuel injection amount, and by moving the adjustment rod in the axial direction of the plunger, the control sleeve is moved up and down to adjust the fuel injection timing. A fuel injection device for an internal combustion engine, characterized in that the fuel injection device is regulated.