JPS6073049A - Fuel-injection pump - Google Patents

Abstract

PURPOSE:To make maximum discharge pressure settable, by installing a read valve in the lower end of a rotary type sleeve as well as installing an adjusting rod, which reduces its mass, free of vertical motion, in case of a jerk type fuel- injection pump. CONSTITUTION:A plunger 1 is pushed upward by a fuel cam and thereby closes a port 3 but the oil hole of a small sleeve 6 is interconnected to an oil feed chamber 5 by way of an oil passage of an adjusting rod 7, therefore pressure is in no case intensified. With successive pushing up, when an oil hole of the small sleeve 6 is closed, pressure inside a plunger chamber 4 goes up and discharge gets starting. When further the plunger goes up and its controlling groove's lower part adjoins the port 3, fuel flows into the oil feed chamber 5 from a chamber 4 and the discharge comes to an end. With this adjusting rod 7 moved up and down, discharge timing is adjustable whereby maximum pressure inside a cylinder of an engine is controllable. When the adjusting rod 7 is situated in a more upper position than that in a plunger stroke, the fuel is no longer discharged so that the engine is stoppable.

Description

[Detailed description of the invention] The present invention relates to improving the performance of fuel injection bombs.

As shown in Fig. 1, a conventional jerk-type fuel injection pump has a structure in which a 20 langeer 1 with a control groove reciprocates within a sleeve 2, pressurizes fuel to high pressure, and sends it to the injection valve as shown by arrow A. be.

The fuel begins to be pressurized in the state shown in FIG. 1 in which the top edge of the control ri'i of the flanger 1 closes the refueling boat 3, and is discharged to the injection valve. Furthermore, 70 Lancia 1 rose and 1lil Ji
When the high-pressure fuel returns to the fuel supply chamber 5 in the state shown in FIG. 2 in which the lower part of the l groove is applied to the fuel supply port 3 and the pressure in the engine chamber 4 decreases by 7°, the discharge ends. Therefore, the position of the top edge of the control groove determines the discharge start, and the position of the control groove 2f7i determines the injection amount of the sintered material.

However, the above method has the following drawbacks.

In recent years, with the low fuel consumption of engines (at 11 in all load ranges)
Has it been attempted to raise the maximum pressure within?

In the conventional method (not shown in FIG. 3), the timing of the discharge start is constant for each nt'l injection, so the in-cylinder pressure at each load is inevitably determined.

Also, in order to increase the maximum internal pressure during operation, it is necessary to adjust the fuel cam, which is a hassle.
It will be a lot of work.

Similarly, when the properties of the fuel to be supplied are different, as shown by sandstone ja in Fig. 3 (in the case of fuel with a low cetane number).

This is inconvenient because the timing changes and the maximum pressure in the cylinder changes.

The purpose of the present invention is to focus on the above points, to be able to freely select the discharge start and injection amount, to set the cylinder maximum pressure as the load condition, and to set the combustion level to 1.
We offer a fuel injection pump that can be set to any value regardless of its properties, and its feature is that in jerk-type fuel injection pumps, it can be set to any value regardless of its properties. By connecting an LJ sleeve with an oil passage, the fuel discharge timing can be varied by vertical movement of an adjustment rod inserted into the sleeve, or by connecting a small plunger with an oil passage to the syringer of the fuel injection pump mentioned above. .

The present invention is equipped with a discharge timing adjustment device that changes the fuel discharge timing by rotating the control grooved small sleeve into which the zero engine gear is inserted.

That is, by connecting a small sleeve or small plunger with an oil passage to a conventional plunger, and rotating the fitted adjustment rod or small sleeve up and down, the discharge timing of the material can be adjusted. It is a spoonful/ζ thing.

In this case, by taking the adjustment rod or the mechanism that rotates the small sleeve to the outside of the pump, you can check the settings externally. - Easily and accurately control the adjustment position.

In addition, by moving the lower end of the adjustment rod above the plunger stroke, the discharge of fuel can be stopped by rotating the small sleeve (separate stoppage can be performed).

4)
1'- of the adjustment mechanism, it is possible to reduce the pressure receiving surface fJ't exposed inside the 70-lunger chamber.
Reduce driving force. Second, by using the drive mechanism as a rotation method, the movable force is reduced.

Moon fueling a small sleeve? 7J for a device that leads out of the 7°
By using the 7.1 adjustment, the sliding area is reduced and the amount of fuel oil leakage is reduced. Also u:, fuel moon adjustment mechanism?
By storing the fuel inside the pump, the amount of fuel pumped into the tank can be reduced.

Embodiments of the present invention will be described below with reference to the drawings. , FIG. 4 is a sectional view showing essential parts of a fuel injection pump 0 according to an embodiment of the present invention.

In the figure, ■ is a plunger, and 2 is a sleeve.

3 is the port 24 is the plunger chamber, 5 is the oil supply chamber, 6 is the small sleeve on the oil path side, 7 is the adjustment (28 is the cam).

9 is a link mechanism, and 10 is a lever. In addition, A is an injection valve, B is a fuel oil drain, a is a valve seat, and b is a presser fitting.

: Connect the oil passage (1 small hole) no-pro to the 10 l1lJ grooved plungers with pins. Insert the adjusting rod 7 into the cylinder hole provided in the small sleeve 6 to open the oil passage.The adjustment rod 7 is moved up and down by a link-cam mechanism consisting of a cam 8. a link mechanism 9. a lever]0. .

”: Describes the function of the stand constructed as follows.

(1) The fuel flange 1 is pushed up by the fuel cam and the control groove closes the port 3, but the oil hole in the small sleeve 6 communicates with the oil supply chamber 5 through the oil passage of the adjustment rod 7. , the pressure does not increase at this point.

(2) 7° Jinjaj is even more king! yl sir iJ'l
Step 7 (When the oil hole in the small sleeve 6 is closed, the pressure inside the plunger chamber 4 increases and discharge begins.

(3) The plunger further rises and y: Ii', 1 clause If, F section is 1? -1-3, Noisin/Ya'・:!・Gas 1 and stomach 1 flow out from 1 into the oil supply chamber 5, the pressure decreases, and discharge ends.

(4) By moving the adjustment rod 7 up and down, the action at the start of discharge can be adjusted. Adjustment 1. If you move to the lower part of the river, the timing of the discharge will be the same.

If it moves upward, the ejection timing (d, becomes slower.It is important to change the ejection timing)]
1': The r pressure can be controlled.

(5) When the adjustment rod 7 is brought to the plan/jast ``''-p''-ka, the oil hole in the small sleeve is not blocked, so the fuel 1d is not discharged /I:') ＋j It is possible to stop the fireworks.

The above case has the following effects.

The present invention was previously proposed by the applicant.
Sleeve of I injection pump (patent application 1977-45 (3:33 bow)).

This is an improvement over the combination of small plungers.

By moving the adjustment rod 7 up and down using the lever 10, 972 mechanism 9 and the norm 8 to change the timing at which the oil drain hole of the small sleeve with oil passage 6 is closed, the timing of fuel discharge is changed, and an arbitrary Pmax can be set. Obtainable.

The structure of the sleeve and plunger is reversed in order to reduce the variable force by reducing the mass of the adjusting rod 7 and reducing the pressure-receiving surface roughness of the adjusting rod 7. At the same time, the gaps between each part can be reduced, and the area of the remaining gaps is also reduced, which improves sealing performance and reduces the amount of fuel oil leakage.

FIG. 5 is a sectional view showing essential parts of a fuel injection pump according to another embodiment of the present invention.

In the figure, 1 is a plunger and 2 is a sleeve.

3 is ;]? -)+4 is the plunger chamber, 5 is the oil supply chamber.

11 is a small plunger with an oil passage, 12 is a small sleeve with an oil passage, 3 is an adjustment tube, and 14 is an adjustment rack.

! Ii! Connect the small 0-jinja 11 with an oil passage to the head of the I-mizuhiki fu0-run 7ya1 with a pin. To small plunger 11.

A small sleeve 12 with a control groove provided at the bottom is fitted.

The small sleeve 12 is provided with an oil passage and communicates with the oil supply chamber 5. The small sleeve 12 is rotated by an adjustment rack 14 via an adjustment tube]3.

The cores of the small sleeve 12 and plunger 1 are tied together.

Let's take a look at the effects of the above configuration.

(1) The control groove pushed up by the plunger 1 by the fuel cam closes the port 3, but since the oil passage of the small plunger 1 is connected to the oil supply chamber 5, the pressure does not increase at this point.

(2) Small plunger 1] is further soil y1 shi, small s IJ-
If the oil passage is blocked by the control groove provided at the bottom of the tube 12,
The pressure in the plunger chamber 4 increases and discharge begins.

(3) When the plunger 1 further rises and the lower part of the control groove of the plunger touches the port 3, fuel from the plunger chamber 4 flows into the oil supply chamber 5, the pressure decreases, and the discharge ends.

(4) By operating the adjustment rack 1/1 and rotating the small sleeve 12, the position of the control groove at the bottom of the small sleeve 12 relative to the oil hole of the small plunger 11 changes. Therefore,
The timing of fuel discharge can be adjusted.

The above case has the following effects.

The sleeve is of a rotating type, and a lead is provided at the lower end of the sleeve, and an adjustment tube 13 is provided to further reduce the mass of the sleeve. A rack 1 is provided inside the pump. Therefore, no consideration is given to leakage of one song from each part.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing the main parts of a conventional fuel injection pump, Fig. 2 is an explanatory diagram without showing the state of the discharge path of the pump in Fig. 1, and Fig. 3 is a sectional view showing the main parts of a conventional fuel injection pump. Fig. 4 is a diagram showing the relationship between timing, injection amount, and maximum cylinder pressure; An explanatory diagram showing a part of the fuel injection pump according to the embodiment, FIG. 6 is a cutaway view taken along the line A-A in FIG. 5, and FIG. Fig. 2 and Fig. 8 are explanatory diagrams showing the lead shape. 1...Plunger, 6...Small sleeve 27...ii
i'l J! ta 4"l\.]J...Small sleeve, 12-fill 6JJE" small sleeve. v A Ushiichi 72 Figure 50% 75% 100% Teishu Figure 3 Figure 5 Figure 7i-6 Off Kasumi

Claims (1)

[Claims] 1. In a jerk type fuel injection pump, is the same fuel injection 1j? A small sleeve with an oil passage is connected to the 7° lange of the pump, and the fuel discharge timing is made variable by the vertical movement of an adjusting rod inserted into the equal-rate sleeve. A small plunger with an oil passage is connected to the zero plunger, and the discharge timing of fuel i-1 can be varied by rotating a small sleeve with a control groove into which the plunger is inserted.'J! ]Fuel injection pump 0゜ characterized by being equipped with a regulating device.