JPS5846657B2 - engine fuel injector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates primarily to a fuel injection device for engines for automobiles and other vehicles.

Conventionally, this type of device has a flapper plate located upstream of the throttle valve in the intake passage of the engine, and as the covering plate rotates, a meter inserted in the fuel passage is rotated to adjust the fuel. Types in which the metering valve is measured are known, but in this case, the flapper plate and the metering valve are generally fixed on a single rotating shaft, and In some cases, the pulsation of airflow in the intake passage causes chattering on the flapper plate, which causes the metering valve to repeatedly rotate in forward and reverse directions, making it impossible to obtain accurate metering. The effect is significant during load operation.

The object of the present invention is to obtain a device that does not have such inconveniences.A flapper plate is provided in the intake passage of an engine on the upstream side of the throttle valve, and as the flapper plate rotates, the fuel In a type in which a metering valve inserted in a passage is rotated to measure the amount of fuel, the rotation axis of the flapper plate and the valve shaft of the metering valve are formed separately from each other. The rotation shaft of the flapper plate and the valve shaft are rotationally engaged with each other via an intermediate retaining member so as to change the rotation ratio between the rotation shafts of the flapper plate and the valve shaft.

An example of implementing the present invention will be explained with reference to the attached drawings.

In the drawings, reference numeral 1 indicates an intake passage of the engine, and a flapper plate 3 is disposed in the passage 1 on the upstream side of the throttle valve 2 so as to be rotatable about a rotation shaft 4 on one side, and thus is attached to the intake passage. Rotation is given according to the amount of air inflow.

In the drawing, reference numeral 5 denotes a return spring that elastically biases the cover plate 8 toward the closing side via the shaft 4.

A rotatable metering valve 7 is provided above the intake passage 1 and housed in a valve housing 6 on the outer periphery, and is connected to a fuel passage between a fuel tank and an injection nozzle at an inlet 8 and an outlet 9. The valve 7 is of a type in which the degree of opening of the valve hole, and thus the amount of fuel passing through it, gradually increases as the rotation angle increases.

In the drawings, reference numeral 11 indicates the valve shaft on the bottom surface of the center thereof, and reference numeral 12 indicates the pressure regulating valve on one side thereof.

In the conventional device, the rotation shaft 4 and the valve shaft 11 are integrally formed with each other, so that when the flapper plate 3 rotates, the metering valve 7 rotates in a corresponding manner, and accordingly, the amount of fuel flows in a corresponding manner. However, some methods have the above-mentioned disadvantages.

The present invention eliminates this inconvenience, and the two shafts 4.degree. 11 are formed separately from each other and are rotatably engaged with each other via a retaining member 13 located between them.

FIG. 1 and FIG. 2 show an example of the engagement member 1.
3 consists of arms 14.15 extending in each radial direction from the rotation shaft 4 and the valve shaft 11, and a link 16 that connects both arms 14.15 to each other. By making them different from each other, the rotation ratio between the rotation shaft 4 and the valve shaft 11 is changed.

To explain this in detail, when the rotating shaft 4 rotates in the state shown in the second figure, the distal end of the arm 14 extending from the shaft 4 has a relatively small displacement in the left-right direction, and therefore, the displacement of the valve shaft 11 in the left-right direction is relatively small. Although the rotation angle is relatively small, the next time the rotation shaft 4 rotates significantly, the left-right direction device at the tip of the arm 14 becomes relatively large, and the rotation angle of the valve shaft 11 accordingly increases. I did it like that.

In other words, when the flapper plate 3 opens more or less from its closed position, the rotation angle generated in the metering valve 7 is relatively small; next, when the flapper plate 3 opens wide, the rotation angle generated in the metering valve 7 is relatively small. The angle of movement was made to gradually become relatively large.

The figure shows an idle adjustment nut interposed in the middle of the 17-bar link 16.

FIG. 3 shows a modification of the engagement member 13, in which the engagement member 13 is supported by a cam 18 on the rotating shaft 4 and an arm 15 extending radially from the valve shaft 11 via a spring 2B, and is adjusted. screw 2
and a follower 19 having a follower 30 that adjustably comes into elastic contact with the cam 18 via the cam 18.
8 is shaped so that the change in the height of the cam crest gradually increases, so that when the flapper plate 3 gradually opens, the metering valve I gradually opens, but its rotation angle is initially relatively small and gradually increases. .

The engaging member 3 is equipped with a negative pressure responsive member 20, and the one shown in FIGS. 1 and 2 will be described first.
0 consists of a diaphragm that is elastically repelled forward by a spring 22 on the front surface of a negative pressure chamber 21, and the inside of the negative pressure chamber 21 is a negative pressure area clue 23 in the intake passage 1 between the throttle valve 2 and the flapper plate 3. A rod 25 extending forward from the diaphragm is connected to an arm 26 extending from the valve shaft 11 to the other side through a long hole 21, thus opening the throttle valve 2. When the engine suddenly accelerates, the passage 1
A large negative pressure is generated inside the member 20, which acts on the back surface of the member 20 and moves it backward against the spring force of the spring 22, giving the valve shaft 11 an opening-side rotation via the rod 25. I made it possible to do so.

In this way, the metering valve 6 is forced to open by this negative pressure, thereby making it possible to cope with malfunctions caused by the ingress of dust and other foreign matter, and to eliminate poor responsiveness of the flapper plate 3 during rapid acceleration.

Also, during normal operation, the negative pressure in the intake passage 1 is small, so
The small movement of the diaphragm 20 does not cause the valve shaft 11 to rotate open due to the elongated hole 27, and the valve shaft 11 rotates open only in response to the opening of the flapper plate 3.

The one shown in FIG. 3 is substantially the same, but in this case, the rod 25 extending from the negative pressure responsive member 20 is connected to the follower 19, so that when the negative pressure is activated, the metering valve is connected via the follower 19. 7 is forced to the open side, but the cam 18 and the flapper plate 3 connected thereto are not affected by this.

To explain its operation, the flapper plate 3 adjusts its opening degree according to changes in the air flow inside the intake passage 1.
Along with this, the metering valve 7 is automatically adjusted to the corresponding opening degree, and this point is not particularly different from the conventional one, but in this case, the flapper plate 3 and the metering valve 7 are located between the flapper plate 3 and the metering valve 7. The rotation ratio is changed by being rotationally engaged through the engagement member 13 of , and when the flapper plate 3 is at a low opening degree,
The rotation angle of the flapper plate 3 is relatively small, so that the influence of chattering of the flapper plate 3, which tends to occur particularly when the engine is operated at low load, is reduced.

In this way, according to the present invention, the rotation axis of the flapper plate and the valve axis of the metering valve are formed separately from each other, and the rotation axis of the flapper plate is connected to the rotation axis of the flapper plate through an intermediate retaining member. Since the rotary shaft and the valve shaft are rotatably engaged with each other so as to change the rotation ratio between the fully closed position and the fully open position, the flapper plate, which is particularly likely to occur when the engine is operated at low load, is This has the effect of preventing the influence of chattering from being transmitted to the valve shaft of the metering valve, thereby enabling accurate metering.

[Brief explanation of the drawing]

FIG. 1 is a cutaway side view of one example of the device of the present invention, FIG. 2 is a plan view of its essential parts, and FIG. 3 is a plan view of a modified example thereof. 1... Intake passage, 2... Throttle valve, 3...
...Flapper plate, 4...Rotation axis, 7...
...Metering valve, 10...Fuel passage, 11...
... Valve stem, 13... Engagement member.

Claims (1)

[Scope of Claims] 1. A flapper plate is provided in the intake passage of the engine upstream of the throttle valve, and as the flapper plate rotates, a metering valve interposed in the fuel passage is rotated, thereby increasing the amount of fuel. In a type in which metering is performed, the rotation shaft of the flapper plate and the valve shaft of the metering valve are formed separately from each other, and the rotation of the flapper plate is controlled through a retaining member located between them. A fuel injection device for an engine, wherein the rotary shaft and the valve shaft are rotatably engaged with each other so as to change the rotation ratio between the fully closed position and the fully open position of the rotary shaft. 2. The fuel for an engine according to claim 1, wherein the engaging member is comprised of arms in each radial direction extending from the rotating shaft and the valve shaft, and a link that interconnects both arms. Injection device. 3. The fuel injection device for an engine according to claim 1, wherein the engaging member comprises a cam on the rotating shaft and a follower extending from the valve shaft and engaging with the cam.