JPS58152168A - Mixture supplying device of multicylinder internal-combustion engine - Google Patents

Abstract

PURPOSE:To enable to supply favorably atomized mixture to each cylinder with favorable distribution with no need to employ the same number of fuel injection valves as the number of cylinders. CONSTITUTION:Each of the fuel injection valves 18 and 19 is equipped with a needle holder 23 at its tip. The needle holder 23 is equipped with a fuel nozzle 24, which is open and closed by means of a needle 25 at its tip. Furthermore, a cap member 26 is attached on the outer periphery of the needle holder 23 in such a manner as to cover the frontal surroundings of the fuel nozzle 24. The cap member 26 is equipped with an air intake port 27 at its side and a nozzle 28 at its tip. The respective air passages 32 are provided at the concentrated pipe part of suction manifolds 12 and 13 respectively and communicated to each other through a bridge part 33 laid between the suction manifolds 12 and 13 and supplied with air through an air conduit 34.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mixture supply device for a multi-cylinder internal combustion engine having a plurality of cylinders, and more particularly to a mixture supply device for a fuel-injected multi-cylinder internal combustion engine.

Conventionally, in a fuel injection multi-cylinder internal combustion engine, a fuel injection valve is provided in each branch pipe part of an intake manifold that guides intake air to each cylinder, and liquid fuel is supplied to each cylinder by this fuel injection valve. Therefore, the same number of fuel injection valves as the number of cylinders are used.

In addition, in the type of fuel-injected multi-cylinder internal combustion engine described above, in most cases, each cylinder is provided with a fuel injection valve, but the fuel injection valve of each cylinder is independent of the stroke of each cylinder. All fuel injections are performed at the same time, so in some cylinders fuel injection occurs when the intake valve is closed, and in other cylinders fuel injection occurs when the intake valve is open. The air-fuel mixture is introduced into each cylinder differently, and most of the liquid fuel injected when the intake valve is closed is once attached to the inner wall of the intake port and the intake valve. This causes a delay in the supply of fuel into the cylinder, leading to a deterioration in response.

The present invention provides a multi-cylinder internal combustion engine that does not require the same number of fuel injection valves as the number of cylinders, the introduction state of the air-fuel mixture to each cylinder is the same for each cylinder, and the air-fuel mixture distribution characteristics for each cylinder are excellent. The purpose is to provide a gas mixture supply container.

The invention will now be described in detail by way of example embodiments with reference to the accompanying drawings.

FIG. 1 is a schematic vertical cross-sectional view showing one embodiment of a mixture supply device for a multi-cylinder internal combustion engine according to the present invention, and FIG. 2 is a plan view of the multi-cylinder internal combustion engine shown in FIG.

In these figures, 1 indicates an internal combustion engine, and the internal combustion engine has a cylinder block 2 and a cylinder head 3, and the cylinder block 2 has a plurality of cylinders formed therein. In the embodiment, four cylinder bores 4 each receive a piston 5, above each of which a combustion chamber 6 is defined in cooperation with the cylinder head.

In FIG. 2, #1 indicates the first cylinder, #2 indicates the second cylinder, #3 indicates the third cylinder, and #4 indicates the fourth cylinder.

The cylinder head 3 is filled with a mixture of fuel and air.
An intake boat 7 is formed which leads to each of the intake ports 7, and each intake port 7 is opened and closed by an intake valve 8. Furthermore, an exhaust boat 9 is formed in the cylinder head 3 for discharging exhaust gas from each combustion chamber 6, and each exhaust boat 9 is opened and closed by an exhaust valve 10. A branch pipe portion of an exhaust manifold 11 is connected to each of the exhaust boats 9.

Branch pipe portions 12b of one intake manifold 12 are connected to the intake boats 7 of the first and second cylinders, and another intake manifold 13 is connected to the intake boats 7 of the third and fourth cylinders. The branch pipe portions 13b are connected to each other. The intake manifolds 12 and 13 are connected to the air outlet of the surge tank 14 at their collecting pipe portions 12a and 13a, respectively. When air enters the surge tank 14, a throttle body 16 having a throttle valve 15 and an intake pipe 17 are used.
are connected in order.

Collecting pipe portions 12a and 1 of intake manifolds 12 and 13
3a are each fitted with one fuel injection valve 18,19. The fuel injection valves 18 and 19 are each supplied with liquid fuel such as gasoline from a fuel tank (not shown) through fuel supply pipes 20 and 21, and the microcomputer 22
The valve opening timing and valve opening time are determined based on the signal generated by 1i11.
1. Microcomputer 22
In this embodiment, the throttle opening detected by the throttle opening sensor 53 and the distributor 54 are
The valve opening timing and valve opening time are controlled based on the crank angle detected by a crank angle sensor 55 provided in the engine.

As best shown in FIG.
9 has a needle holder 23 at its tip, and this needle holder also has a fuel nozzle 24 at its tip. It is designed to be used. A cap member 26 is attached to the outer periphery of the needle holder 23 so as to surround the front periphery of the fuel injection port 24 . This cap member 26 has an air intake port 27 on its side and a spout 28 at its tip.

Both the needle guide 23 and the cap member 26 are attached to the mounting hole 2 formed in the collecting pipe portion of the intake manifold 12.13.
9, and its root and tip portions are sealed by a sealing member 30 and an O-ring 31, respectively.

Further, air passages 32 are provided in the collecting pipe portions of the intake manifolds 12 and 13, respectively, and these air passages 32 communicate with each other through a bridge portion 33 provided in the darkness between the intake manifolds 12 and 13. Air is supplied from 34. Further, the air passage 32 is an air passage 3 provided in each of the intake manifolds 12 and 13.
5 and communicates with the inside of the mounting hole 29. Amount of air! 34 is connected to an air control valve 36 at the other end, and controls a portion of the air flowing through the intake pipe 17 by controlling the amount of air! Air control valve 36 via 37
The flow rate is metered and supplied.

The operation of the air control valve 36 is controlled by the microcomputer 22, and mainly controls the intake air amount during idling operation.

The microcomputer 22 determines the fuel injection timing and fuel injection time of the fuel injection valves 18 and 19 based on a signal from a crank angle sensor 38 that detects cylinder discrimination and rank angle, and a signal from a throttle ey+m sensor (not shown). As a result, the fuel injection valves 18 and 19 inject the required amount of fuel into each intake stroke when the cylinders in charge of the respective cylinders, that is, the cylinders that are connected through the intake manifold, are in the intake stroke. It is designed to be injected into the collecting pipe section of the manifold.

FIG. 4 shows the intake stroke period, fuel injection timing, and ignition timing of each cylinder. In this Fig. 4, the shaded area indicates the intake stroke period of each cylinder, the arrow AI8 indicates the fuel injection timing of the fuel injection valve 18, the arrow A+t indicates the fuel injection timing of the fuel injection valve 19, and the arrow B indicates the ignition timing. Each period is indicated.

With the above configuration, when each cylinder is in its intake stroke, that is, when the intake valve 8 is open, liquid fuel is injected into the intake manifold 12 or 19 from the fuel injection valve 18 or 19 corresponding to that cylinder. It is injected into 13 branch pipes. At this time, due to the differential pressure between the upstream and downstream sides of the throttle valve 15, air is transferred to the air conduit 37, the air control valve 36,
Amount of air! 34, air passages 32, 35, and attachment holes 29, enters the cap member 26 from the air intake port 27, and flows into the branch pipe portion of the intake manifold from the injection port 28 together with the fuel injected from the fuel injection port 24. This promotes atomization of the liquid fuel injected from the fuel nozzle 24, and this liquid fuel further flows into the fIA combustion chamber 6 via the branch pipe section and the intake boat 7 on the intake air flowing in the intake manifold. . This prevents an increase in the amount of fuel droplets adhering to the inner wall of the intake passage, even if the fuel injection valve is installed in the collecting pipe of the intake manifold, which is far away from the intake boat, and contains sufficiently atomized fuel. Combustion is improved by the air-fuel mixture flowing into the combustion chamber 6, resulting in improved fuel efficiency and transient response.

During idling, the throttle valve 15 is in a nearly fully closed position, so the amount of intake air at this time is substantially controlled by the air control valve 36. During load operation other than idling operation, air is supplied to the air intake port 27 of the cap member 26 by keeping the air control valve 36 at an appropriate idling opening degree or fully opening it. This air promotes atomization of the injected fuel.

In addition, during load operation, if a large differential pressure is not maintained between the upstream and downstream sides of the throttle valve 15 and the air necessary for fuel atomization is not secured, as shown in Figure 1. An air pump 38 may be provided as shown by the broken line.

FIG. 5 is a plan view showing another embodiment of the air-fuel mixture supply device according to the present invention. Note that parts in FIG. 5 that correspond to those in FIG. 2 are designated by the same reference numerals as in FIG. 2. In this embodiment, the intake manifold 12 is configured to guide intake air to the first and third cylinders, and the intake manifold 13 is configured to guide intake air to the second and fourth cylinders. Fuel injection valves 18 and 19 are provided in the collecting pipe portions of the fuel injection valve 18 and 19, respectively, in the same manner as in the embodiment described above. Further, in this embodiment, the air passage 32
An air passage equivalent to that is provided by the delivery vibe 39.

FIG. 6 shows the intake stroke period, fuel injection timing, and ignition timing of the multi-cylinder inner layer II shown in FIG. 5, respectively. The symbols in FIG. 6 are the same as those in FIG. 4.

Therefore, it will be understood that the embodiment shown in FIG. 5 has the same effects as the embodiment shown in FIGS. 1 to 3.

FIG. 7 is a plan view showing one embodiment in which the air-fuel mixture supply @ value according to the present invention is implemented in a 6-gas casting m* section. Furthermore, the seventh
In the figures, parts corresponding to those in FIG. 2 are designated by the same reference numerals as in FIG. 2. In this embodiment, the internal combustion engine 1 has six cylinders No. 1 to No. 6, and the No. 1 and No. 2 cylinders are connected to the intake manifold 40, and the No. 3 and No. 4 cylinders are connected to the No. 3 and No. 4 cylinders. An intake manifold 41 supplies intake air to cylinder No. 5 and a cylinder No. 61 through an intake manifold 42, respectively. Fuel injection valves 44 to 44 are provided in the collecting pipe portions of each of the intake manifolds 40 to 42.
46 are attached, and these fuel injection valves are adapted to inject the required amount of liquid fuel when the cylinder to which they each serve is on its intake stroke. Also, in this embodiment, air conduction is also used! 34, air is supplied around the fuel nozzle of each fuel injection valve through the delivery pipe 39, and this air promotes atomization of the liquid fuel injected from the fuel nozzle.

FIG. 8 shows the intake stroke period, fuel injection timing, and ignition timing of each cylinder of the multi-cylinder internal combustion engine shown in FIG. 7.

In FIG. 8, A44 indicates the fuel injection timing of the fuel injection valve 44, A4B indicates the fuel injection timing of the fuel injection valve 45, and arrow A
46 indicates the injection timing of the fuel injection valve 46, respectively.

FIG. 9 shows still another embodiment of the mixture supply @ stirrup for a multi-cylinder internal combustion engine according to the present invention.

In this embodiment, the first, second, and third cylinders receive intake air from an intake manifold 47, and the fourth, fifth, and sixth cylinders receive intake air from another intake manifold 48. A fuel injection valve 49,50 is provided in the collecting pipe portion of each intake manifold. The fuel injection valves 49 and 50 are configured to inject fuel when the cylinders with which they are communicated through the intake manifold are in the intake stroke. Also in this embodiment, air is supplied around each fuel nozzle of the fuel injection valve 49,50 through the air guide 134 and the delivery pipe 39 in the same manner as shown in FIG. Atomization of the liquid fuel injected from the fuel nozzle is promoted.

FIG. 10 shows the intake stroke period, fuel injection timing, and ignition timing of the multi-cylinder internal combustion engine shown in FIG. 9, respectively. In FIG. 16, Aa indicates the fuel injection timing of the fuel injection valve 49, and Am indicates the fuel injection timing of the fuel injection valve 50.

In any of the embodiments described above, it is possible to supply a mixture of fuel and air in a well-integrated state to each cylinder with good distribution without requiring the same number of fuel injection valves as the number of cylinders.
Combustion is improved, and fuel efficiency and transient response are improved accordingly.

[Brief explanation of drawings]

FIG. 1 is a sectional view II showing a mixture supply system for a multi-cylinder internal combustion engine according to the present invention, FIG. 2 is a plan view of the multi-cylinder internal combustion engine shown in FIG. 1, and FIG. FIG. 4 is an enlarged vertical cross-sectional view showing the fuel injection valve mounting portion of the multi-cylinder internal combustion engine shown in FIG. 2, and FIG. A graph showing the injection timing and the ignition timing gate, FIG. 5 is a plan view showing another embodiment of the mixture supply device for a multi-cylinder internal m-engine according to the present invention, and FIG. 6 is shown in FIG. FIG. 7 is a graph showing the intake stroke period, fuel injection timing, and ignition timing of a multi-cylinder internal combustion engine; FIG. 7 is a plan view showing another embodiment of the air-fuel mixture supply device for a multi-cylinder internal combustion engine according to the present invention; FIG. is a graph showing the intake stroke period, fuel injection timing, and ignition timing of the multi-cylinder internal combustion engine shown in FIG. 7, and FIG. Plan view showing the embodiment, No. 10
The figure shows the intake stroke period of the multi-cylinder internal combustion engine shown in FIG.
It is a graph showing fuel injection timing and ignition timing. 1... Internal combustion engine, 2... Cylinder block, 3...
・Cylinder head, 4... cylinder pore, 5... piston. 6... Combustion chamber, 7... Intake port, 8... Intake valve, 9... Exhaust boat, 10... Exhaust valve, 11...
Exhaust manifold, 12.13... Intake manifold, 15... Throttle valve, 16... Throttle body, 17... Intake pipe, 18.19... Fuel injection valve,
, 20.21...Fuel supply pipe, 22...Microcomputer, 23...Needle holder, 24...Fuel injection 0.25...Needle, 26...Cap member, 27... Air intake. 28... Spout, 29... Mounting hole, 30... Seal member. 31...0 ring, 32...air passage, 33...
Bridging part, 34... Air conduit, 35... Air passage,
36...Air control valve, 37...Air conduit, 38...
・Air pump. 39...Delivery pipe, 40-42...Intake manifold, 44-46...Fuel injection valve, 47.48.
...Intake manifold, 49.50...Fuel injection valve,
53... Throttle opening sensor, 54... Distributor, 55... Crank angle sensor Fig. 5 Fig. 6 2 Noah 2 angle Fig. 7 Fig. 8 2 Rank angle

Claims (1)

[Claims] (1) An intake passage that guides intake air to each of a plurality of cylinders, a fuel injection valve provided at a gathering part of the intake passage, and supplying air to the intake passage from around the fuel injection port of the fuel injection valve. A mixture supply device for a multi-cylinder internal combustion engine, comprising an air supply device. (2. In the air-fuel mixture supply device as set forth in claim 1, the fuel injection valve is configured to perform a fuel injection operation on the intake line 8Wl of each cylinder. Mixture supply system for multi-cylinder internal combustion engines.