JPS6157454B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel supply system for an internal combustion engine, and more particularly to an improvement in a fuel supply system in which a fuel injection valve is provided in a variable bench lily portion formed by a movable piston.

It is well known that the combustion of fuel in an internal combustion engine is generally more stable and more efficient as the fuel is atomized. Therefore, fuel supply devices equipped with fuel injection valves that atomize fuel and supply it into the intake passage have come into use, but conventional devices lack responsiveness to changes in intake air volume and accuracy in detecting intake air volume. The device had many problems and was relatively expensive. For this reason, JP-A-49
As disclosed in Japanese Patent No. -70027, a device has also been proposed in which the amount of fuel injection is set according to the amount of intake air passing through the intake pipe.

SUMMARY OF THE INVENTION An object of the present invention is to provide a movable piston type fuel supply device that improves fuel atomization and consumption rate, has good responsiveness to changes in intake air volume, and is suitable for accurately measuring intake air volume. year,
A throttle valve provided in an intake cylinder of an internal combustion engine, one fuel injection valve, and a movable piston inserted into the intake cylinder and forming a variable bench lily that moves in relation to the amount of air passing through the intake cylinder. and a control device that outputs an electric signal related to the amount of movement of the movable piston, the internal combustion engine configured to control the amount of fuel supplied from the fuel injection valve based on the output signal from the control device. In the fuel supply device, the one fuel injection valve is provided in the variable bench lily portion, the movable piston is movably housed in a suction chamber, and the movable piston is disposed concentrically with respect to a suction rod attached to the center of the movable piston. A cylindrical portion formed in the suction chamber is integrally formed with the suction chamber, an electromagnetic coil for detecting the amount of movement of the suction rod is fixed to the cylindrical portion, and the movable piston is concentric with the electromagnetic coil. The electromagnetic coil is characterized in that it has a portion made of a magnetic material that causes a change in magnetic flux in the electromagnetic coil.

FIG. 1 is a sectional view of essential parts for explaining a fuel supply device which is an embodiment of the present invention. The intake cylinder 3 is connected to the engine 1 via the intake manifold 2, and the intake cylinder 3 is provided with a throttle valve 4 for controlling the amount of intake air. A movable piston 5 is inserted into the intake cylinder 3, and the movable piston 5 and the fixed wall 19 form a variable vent lily portion 6, so that the ventilation cross-sectional area is changed.

The movable piston 5 slides in the suction chamber 7, and the negative pressure generated by the air flow in the variable bench lily portion 6 is transferred to the suction chamber 7 through the ventilation hole 9.
be introduced within. The atmospheric chamber 10 communicates with outside air through a small hole provided in the suction chamber 7, thereby facilitating the movement of the movable piston 5. The movable piston 5 maintains the difference between the negative pressure in the suction chamber 8 and atmospheric pressure,
Movement is stopped when the pressure receiving area and weight of the movable piston 5 and the spring force of the suction spring 11 are balanced. Further, a suction rod 12 is attached to the movable piston 5, and this suction rod 12 is made of a magnetic material and is movably inserted into the electromagnetic coil 13. That is, since the position of the movable piston 5 changes depending on the amount of intake air as described above, the amount of intake air is detected electrically, and this signal is transmitted to the control device 28.

On the other hand, fuel to be supplied to the engine 1 is pumped from the fuel tank 25 to the fuel injection valve 20 through the fuel pump 24, filter 22, and pressure regulator 21. The amount of fuel injected by the fuel injection valve 20 is determined by the valve opening time and valve opening area, and the control device 28 controls this. Control device 28
A battery 29 is connected to serve as a power source, and in addition to the intake air amount signal, the ignition coil 2
7. Temperature sensor 1 installed inside the air cleaner 15
8. Signals from the exhaust sensor 17 installed in the exhaust pipe 16 are input and processed. Based on these signals, the control device 28 operates the fuel injection valve 20 with an output that injects the optimum amount of fuel.

The fuel injection valve 20 is installed at the opening of the slightly raised fixed wall 19 of the intake cylinder 3, and injects fuel into the variable bench lily part 6 where the intake air flow rate is large and constant, so that the fuel is atomized by injection. The atomization caused by the intake flow rate works synergistically to create a uniformly mixed air-fuel mixture. This air-fuel mixture is evenly distributed to the plurality of intake manifolds 2, which facilitates the operation of the engine 1 and saves fuel consumption. Furthermore, since fuel is supplied from one fuel injection valve 20, the structure can be extremely inexpensive compared to the conventional arrangement in which a fuel injection valve is installed for each cylinder of the engine.

In the fuel supply device of this embodiment, a fuel injection valve is installed in a variable bench lily formed by a movable piston and a fixed wall, and the movable piston is movably housed to control the movement of a suction rod attached to the center of the movable piston. The electromagnetic coil installed in the suction chamber converts it into an electrical quantity for control, and a non-contact displacement detector can be formed compactly inside the suction chamber. Therefore, the structure is simple and easy to assemble.
It is easy to install, can be constructed at low cost, and has the effect of improving fuel efficiency and drivability, and purifying exhaust gas.

FIG. 2 is an enlarged sectional view of essential parts of a fuel supply system that is a modification of FIG. 1, and the same parts as in FIG. 1 are designated by the same reference numerals. The difference from FIG. 1 is that the temperature sensor 18 is installed upstream of the movable bench lily section 6. Air cleaner 1 as shown in Figure 1.
5, there was a problem that when the amount of intake air was small, such as during low-speed operation, it was difficult to measure the true intake air temperature due to the effects of radiant heat and convection of the air cleaner 15. is provided close to the upstream side of the variable bench lily portion 6, so
More accurate intake air temperature can be detected. Therefore,
The accuracy of intake air temperature correction is improved and accurate fuel can be supplied. Further, there is an advantage that the temperature sensor 18 can be more easily attached than the air cleaner 15 and can be more compactly assembled.

By installing the temperature sensor in the upstream intake cylinder of the variable bench lily, the fuel supply device of this embodiment can more accurately correct the temperature of the intake air amount and supply a suitable amount of fuel. It has an effect.

FIG. 3 is an enlarged sectional view of essential parts of a fuel supply system that is a modification of FIG. 1, and the same parts as in FIG. 1 are designated by the same reference numerals. The difference from FIG. 1 is that the pressure sensor 31 is installed on the fixed wall 19.
This pressure sensor 31 converts the pressure of the variable bench lily section 6 into voltage or current, and focuses on the fact that the bench lily pressure during transient operation is different from the steady state, and transmits this signal to the control device 28 during acceleration or deceleration operation. It is designed to increase or decrease the amount of fuel supplied.

In this way, there is little misalignment between the intake air amount detection section and the fuel injection section, so there is no delay in response even to minute changes in the intake air amount.

As described above, the fuel supply device of this embodiment has the effect that the response of the fuel supply amount is good because the intake air amount detection section and the fuel injection section are provided close to each other.

FIG. 4 is an enlarged sectional view of a main part of a fuel supply system which is another modification of FIG. 1, and the same parts as in FIG. 1 are given the same numbers. The device of this embodiment differs from others in that an electromagnetic coil 13 for detecting the position of the movable piston 5 is installed in the suction chamber 7, and a cylindrical magnetic body 32 is attached to the movable piston 5. . The magnetic field generated in the excitation coil of the electromagnetic coil 13 causes the movement of the magnetic body 32,
That is, a change in the lift of the movable piston 5 causes a change in magnetic flux. Therefore, since an electrical change occurs in the detection coil of the electromagnetic coil 13 due to a change in magnetic flux, this change is detected.

The fuel supply device of this embodiment has the effect that the height of the fuel supply device can be reduced by installing the electromagnetic coil in the suction chamber and attaching the magnetic body to the movable piston.

As described above, in the fuel supply device for an internal combustion engine according to the present invention, a movable piston is installed facing a fixed wall on the upstream side of a throttle valve in an intake cylinder, and the movable piston is installed in a suction chamber in which the movable piston is movably accommodated. The amount of movement of this movable piston is electrically detected by an electromagnetic coil installed in the piston, and transmitted to the control device to determine the amount of intake air.The amount of fuel proportional to this amount of intake air is also sent to a fixed wall. Since the fuel is supplied to the variable bench lily from one installed fuel injection valve, the structure of the variable bench lily is simple.
A fuel supply device that is easy to assemble and install, can be constructed at low cost, improves fuel atomization and consumption rate, and can supply fuel in a responsive manner to changes in intake air volume, improving drivability. It has the effect of being able to be configured.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part for explaining a fuel supply device which is an embodiment of the present invention, FIG. 2, FIG. 3,
FIG. 4 is a sectional view of a main part of a fuel supply device of other different embodiments. DESCRIPTION OF SYMBOLS 1... Engine, 3... Intake cylinder, 4... Throttle valve, 5... Movable piston, 6... Variable bench lily part, 7... Suction chamber, 12... Suction rod, 13... Electromagnetic coil, 18 ... Temperature sensor, 19 ... Fixed wall, 20 ... Fuel injection valve,
28...control device, 31...pressure sensor, 32...
...Magnetic material.

Claims (1)

[Scope of Claims] 1. A throttle valve provided in an intake cylinder of an internal combustion engine, one fuel injection valve, and a variable valve inserted into the intake cylinder that moves in relation to the amount of air passing through the intake cylinder. A movable piston forming a bench lily portion,
and a control device that outputs an electric signal related to the amount of movement of the movable piston, the fuel supply for an internal combustion engine configured to control the amount of fuel supplied from the fuel injection valve based on the output signal from the control device. In the apparatus, the one fuel injection valve is provided in the variable bench lily part, the movable piston is movably housed in the suction chamber,
A cylindrical part formed concentrically with the suction rod attached to the center of the movable piston is integrally formed with the suction chamber, and a cylindrical part is provided with a cylindrical part for detecting the amount of movement of the suction rod. A fuel supply device for an internal combustion engine, characterized in that the electromagnetic coil is fixed, and the movable piston has a part made of a magnetic material that is concentric with the electromagnetic coil and causes a change in magnetic flux in the electromagnetic coil. . 2. The internal combustion engine according to claim 1, wherein the part made of the magnetic material is the suction rod, and the electromagnetic coil is installed at the upper part of the suction chamber, into which the suction rod is inserted. Fuel supply device. 3. The part made of the magnetic material is a cylindrical body attached to the movable piston, and the electromagnetic coil is fixed to the cylindrical part so as to be concentric with the cylindrical body. A fuel supply device for an internal combustion engine according to scope 1.