JPH06185436A - Fuel injection device for engine - Google Patents

Abstract

PURPOSE:To improve atmization of fuel injected by a fuel injector, improve combustion efficiency, and reduce intake resistance by arranging a fuel collision plate on an air funnel on an upstream side of an intake passage, driving the fuel collision plate according to variation of an accelerator opening while opening/closing, and thereby adjusting an intake air amount. CONSTITUTION:A fuel injector 9 is provided on an upstream side opening edge 7a of an air funnel 7. An injection part 11 is faced to a center of a fuel collision surface 20a of a fuel collision plate 20, followed by fixation. The fuel collision plate 20 is attachably/detachably supported so as to open and close the upstream side opening of the air funnel 7. Near the fully opened position, a fuel collision surface 20a is opposed to the injection direction of the fuel injector 9 by means of a tilting angle variable mechanism. A slide member 15 is extended or contracted according to extention/contraction of a throttle wire 31. The fuel collision plate 20 is operated through a valve body surface 20b for adjusting an opening rate from the full open condition of the upstream side opening of the air funnel 7 to its full close condition, and thereby an intake air amount is adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine fuel injection device.

[0002]

2. Description of the Related Art In a general engine fuel injection system, a fuel injector for injecting fuel is located upstream of a throttle valve so that fuel is injected from upstream to downstream in a manner along the flow of intake air. It has become. The injected fuel is atomized as much as possible by atomization at the injection port during injection and atomization by heating from the inner wall surface of the intake port after injection.

However, in the vaporization method by the system,
Since it is not always possible to achieve sufficient atomization and vaporization of the injected fuel, and fuel that is not vaporized sufficiently is supplied to the engine combustion chamber through the intake port, the combustibility of the mixture itself is not sufficient and However, there is a problem in that the transportation of fuel is delayed due to the adhesion of the wall surface of Further, there is a problem that the intake resistance is large due to the presence of the throttle valve, and the intake charging efficiency is poor.

Therefore, as a means for solving such a problem and improving combustion performance and combustion efficiency as much as possible, for example, as disclosed in Japanese Utility Model Laid-Open No. 57-18749, the throttle valve in the intake passage is slightly changed. While the fuel injector is provided at the downstream side, the fuel collision plate is provided so as to face the injection direction of the fuel injector, and the fuel injected from the fuel injector is collided with the fuel collision plate to be atomized and then into the combustion chamber. It has been proposed to improve vaporization by introducing it.

Further, in the construction of the device, the operating angle is changed by changing the facing angle of the fuel collision plate directly downstream of the intake air amount adjusted by the upstream throttle valve, that is, the operating load of the engine to the fuel injector. The atomized fuel is supplied to the combustion chamber while adjusting the intake flow velocity according to the above.

[0006]

However, in the configuration,
The presence of the fuel collision plate in addition to the presence of the throttle valve in the intake passage significantly increases the intake resistance, and the flow of intake air that is originally smoothly introduced through the throttle valve is greatly disturbed downstream of the throttle valve. There is a problem that the intake flow velocity is reduced excessively. Therefore,
With the above-mentioned configuration, there is a limit in realizing an engine having a sufficiently large specific output with respect to the displacement.

[0007]

The invention described in each of claims 1 to 5 of the present application has been made for the purpose of solving each of the above problems, and is configured as follows. .

(1) Structure of the Invention According to Claim 1 In the fuel injection device for an engine according to the invention described in claim 1, the fuel collision plate for colliding the injected fuel with the intake passage and the fuel from the downstream side of the fuel collision plate. A fuel injector for an engine, comprising: a fuel injector for injecting fuel in a direction toward an upstream side of an intake air toward a fuel collision surface of the collision plate, wherein the fuel collision plate is arranged in an air funnel portion upstream of the intake passage, and A drive mechanism for driving the fuel collision plate is provided, and the amount of intake air can be adjusted by driving the fuel collision plate according to a change in accelerator opening to open and close the funnel opening by the drive mechanism. It is what

(2) Structure of the Invention According to Claim 2 The engine fuel injection device of the invention according to claim 2 is based on the structure of the invention according to claim 1 as a basic structure, and the fuel collision plate in the structure is the same. It is configured such that it can be tilted in conjunction with the drive by the drive mechanism, and is tilted in a direction facing the fuel injection valve as the fuel collision plate becomes farther from the funnel opening of the air funnel portion. is there.

(3) Structure of the Invention According to Claim 3 The engine fuel injection device of the invention according to claim 3 is based on the structure of the invention according to claim 1 or 2, and the fuel collision in the structure is the same. The plate is configured to fully close the funnel opening of the air funnel portion, and in the fully closed state, intake air is supplied through a groove formed in the fuel collision plate. It is characterized by.

(4) Structure of the Invention According to Claim 4 The fuel injection device for an engine according to the invention of claim 4 is based on the structure of the invention according to claim 3 described above, and the groove portion in the structure is a fuel injector. It is characterized in that it is formed on the side.

(5) Structure of the Invention According to Claim 5 The fuel injection device for an engine according to the invention of claim 5 is based on the structure of the invention according to claim 3 or 4 described above, and the fuel collision in the structure is the same. The plate is characterized in that a heat-generating surface for heating the fuel is provided at a portion where the fuel collides with the funnel opening in a fully closed state or a state close to the fully closed state.

[0013]

The inventions described in each of claims 1 to 5 of the present application are configured as described above, and as a result, they operate as follows corresponding to the configuration.

(1) Operation of the invention according to claim 1 In the fuel injection device for an engine according to claim 1, the fuel collision plate for colliding the injected fuel with the intake passage and the fuel from the downstream side of the fuel collision plate. A fuel injector for an engine, comprising: a fuel injector for injecting fuel in a direction toward an upstream side of an intake air toward a fuel collision surface of the collision plate, wherein the fuel collision plate is arranged in an air funnel portion upstream of the intake passage, and A drive mechanism for driving the fuel collision plate to open and close the funnel opening is provided, and the intake air amount is adjusted by driving the fuel collision plate to open and close the funnel opening in accordance with a change in accelerator opening. You can do it.

Therefore, the fuel injected from the fuel injector is satisfactorily atomized by colliding with the fuel collision plate, and is then satisfactorily vaporized by utilizing the entire length of the intake passage while being mixed with the intake air. As it is supplied to the engine combustion chamber, the combustibility is improved.

Moreover, the fuel collision plate is located outside the intake passage and is driven by the drive mechanism in accordance with the accelerator opening.
The intake air amount that is efficiently supplied to the engine combustion chamber through the large-diameter funnel opening of the air funnel is adjusted in the same way as the throttle valve, so it is possible to use the conventional throttle valve The fuel impingement plate is not needed, and the intake resistance is greatly reduced.

(2) Operation of the invention according to claim 2 In the fuel injection device for an engine according to claim 2, the structure of the invention according to claim 1 is a basic structure, and the fuel collision plate in the structure is the same. The fuel collision plate is tiltable in association with driving by the driving mechanism, and is tilted in a direction facing the fuel injection valve as the fuel collision plate becomes farther from the funnel opening of the air funnel portion.

Therefore, according to this structure, in addition to the same operation as that of the invention described in claim 1, even if the fuel collision plate is separated from the funnel opening, the fuel reflected by collision is always directed toward the center of the intake passage. Therefore, there is no scattering outside the funnel opening or adhesion to the wall surface.

(3) Operation of the invention according to claim 3 The fuel injection device for an engine according to claim 3 is based on the structure of the invention according to claim 1 or 2, and the fuel collision in the structure is the same. The plate is configured to be able to fully close the funnel opening of the air funnel portion, and in the fully closed state, intake air is supplied through the groove formed in the fuel collision plate.

Therefore, according to this structure, in addition to the same operation as that of the invention described in claim 1 or 2, a predetermined amount of intake air can be appropriately supplied at the time of idling and the injected fuel is intake air. Because it is atomized without cooling,
Vaporization is further improved.

(4) Operation of the invention according to claim 4 In the fuel injection device for an engine according to claim 4, the structure of the invention according to claim 3 is a basic structure, and the groove portion in the structure is a fuel injector. Formed on the side.

That is, in this structure, the fuel collision plate can fully close the funnel opening of the air funnel portion, and in the fully closed state, the fuel collision plate is located on the fuel injector side through the groove formed in the fuel collision plate. Intake air is supplied and fuel is injected into the intake air flow.

Therefore, a predetermined amount of intake air can be appropriately supplied even during idling, and the injected fuel collides with the fuel collision plate to be atomized without cooling the intake air and then efficiently mixed with the intake air. Since it is supplied to the engine combustion chamber, the vaporization property at the time of idling becomes good.

(5) Action of the invention according to claim 5 In the fuel injection device for an engine according to claim 5, the structure of the invention according to claim 3 or 4 is the basic structure, and the fuel collision in the structure is the same. The plate is provided with a heat generating surface for heating the fuel at a portion where the fuel collides with the funnel opening in a fully closed state or a state close to the fully closed state.

That is, in this structure, the fuel collision plate can fully close the funnel opening of the air funnel portion, and in the fully closed state, the fuel collision plate is located on the fuel injector side through the groove formed in the fuel collision plate. Intake air is supplied, fuel is injected in the intake air flow direction, and the injected fuel comes into contact with the heat generation surface.

Therefore, a predetermined amount of intake air is appropriately supplied even during idling, and the injected fuel collides with the heat generation surface of the fuel collision plate and is atomized by heating without cooling the intake air. Since it is mixed with and supplied to the engine combustion chamber, the vaporization property at the time of idling becomes good.

[0027]

As a result of the above, according to the invention described in each of claims 1 to 5, the function of adjusting the intake air amount instead of the throttle valve and the atomization of the fuel are replaced only by the fuel collision plate provided in the air funnel portion. In addition, both of the vaporization improving function can be realized at the same time, and the intake charging efficiency can be improved by reducing the intake resistance and a high combustion performance improving effect can be obtained. Further, a substantial effect of varying the intake pipe length can be obtained, and an engine having a large specific output with respect to the displacement can be realized.

[0028]

1 and 2 show the construction of an engine fuel injection system according to an embodiment of the present invention.

In the figure, reference numeral 1 is an engine body of this embodiment, and the engine body 1 is constructed by integrating an upper cylinder head 1A and a lower cylinder block 1B.

Between them, the engine combustion chamber 2
Are formed. An intake port 3 is formed on the wall surface of the cylinder head with respect to the engine combustion chamber 2, and an intake manifold 6 is connected to and integrated with an intake manifold mounting portion 5 of the intake port 3.

The upstream opening end of the intake manifold 6 is connected to the downstream opening end of the air funnel 7 whose diameter is gradually reduced from the upstream side to the downstream side.

An upstream first fuel injector 9 is provided at an upstream opening edge 7a of the air funnel portion 7 via a fuel injector mounting portion 10 having a nozzle hole fitting port 12 formed therein. . The first fuel injector 9 is arranged and fixed so that its injection hole portion 11 faces a central portion of the fuel collision surface 20a of the fuel collision plate 20 provided so as to face the upstream opening of the air funnel 7. On the other hand, as shown in the figure, the fuel collision plate 20 is supported by an expansion / contraction actuating mechanism so as to be separable / separable so as to open / close the upstream side opening of the air funnel 7, and the tilt angle is variable near the fully open position apart from the opening. The mechanism allows the fuel collision surface 20a to face the direction of the injection port of the first fuel injector 9. On the fuel collision surface 20a of the fuel collision plate 20, the fuel injected from the first fuel injector 9 collides and is atomized efficiently, and the reflected fuel is generated by the air funnel portion 7 and the intake manifold 6 as shown by the arrow. The flat surface is such that it is introduced in the central axis direction of the formed intake passage without adhering to the wall surface. Then, the fuel collision surface 2
A tapered valve body surface 20b that completely closes the upstream opening of the air funnel 7 is provided around 0a.

The expansion / contraction mechanism of the fuel collision plate 20 is constructed as follows.

That is, reference numeral 14 is a fuel collision plate holding member, and the fuel collision plate holding member 14 is provided with a plurality of bolt members 13 having a spacer function and having a predetermined length. 7 is attached to the upstream opening edge 7a.

A slide member fitting hole 14b is provided at a central shaft portion position of the boss portion 14a formed in the central portion of the fuel collision plate holding member 14 which coincides with the central axis of the air funnel 7.
Are formed. In addition, the slide member fitting hole 14b
The tip end surface of the boss portion 14a (opposing surface facing the upstream opening of the air funnel 7) is inclined so as to be orthogonal to the central axis of the injection port portion of the first fuel injector 9 so as to surround the boss portion 14a. A sleeve 16 is provided, and the sleeve 16 forms the tilt angle varying mechanism of the fuel collision plate 20 described above.

On the other hand, reference numeral 15 is, for example, a cylindrical slide member, and the slide member 15 is loosely fitted in the slide member fitting hole 14b of the fuel collision plate holding member 14 and slidable in the axial direction. Has become. A central boss portion 23 having a concave portion of the fuel collision plate 20 is tiltably connected to a front end portion 15a of the slide member 15 on the air funnel 7 side via a spherical body 24, while the other rear end portion 15b is tilted. The rear end of the throttle wire 31 of the push-pull cable 28 is connected to the rear end of the push-pull cable 28 via the connecting member 30. The push-pull cable 28 has a base portion 29.
Is fixedly supported by a fixing bracket 26 attached to the fuel collision plate holding member 14. Further, the fuel collision plate 20 is not tilted between the fuel collision plate 20 and the boss portion 14a of the fuel collision plate holding member 14 when it is not tilted.
A return spring SP for positioning is disposed to position the engine at a position orthogonal to the intake passage.

Therefore, the slide member 15 has a depression angle (accelerator opening θ) of the accelerator pedal as shown in FIG.
Arrow corresponding to the expansion and contraction of the throttle wire 31 corresponding to
From the state (full load state) in which the upstream side opening of the air funnel 7 is fully opened by the valve body surface 20b of the fuel collision plate 20 as shown in FIG. As shown in FIG. 2, the opening amount is arbitrarily adjusted (height adjustment) until the same opening is fully closed (idle state) to adjust the intake air amount according to the operating state. Moreover, as shown in FIG. 4, the fuel collision plate 20 moves away from the low height state where the accelerator opening θ is increased and the upstream side opening portion of the air funnel 7 is fully closed, and the fuel collision plate 20 is fully opened with a high height. The fuel impingement surface 20a is gradually inclined by a desired angle α in the direction facing the injection port 11 of the first fuel injector 9 due to the action of the inclined surface on the tip side of the sleeve 16 as it approaches. . Therefore, the gap between the valve body surface 20b and the inner peripheral surface of the upstream opening edge 7a of the air funnel 7 from the state where the upstream opening of the air funnel 7 is close to the fully closed state to the state where it is fully opened. Is narrow and the intake air velocity from the periphery of the valve body surface 20b is fast and the injected fuel is not scattered to the upstream side or adhered to the wall surface, the fuel injection to the fuel collision surface 20a of the fuel collision plate 20 is 90 °. The fuel injection is performed at a predetermined inclination angle larger than that, and the fuel atomized by the collision is smoothly introduced by being placed on the intake air in the central axis direction of the air funnel 7, and it is sufficient in the intake air introduction process to the engine combustion chamber 2. Vaporize.

On the other hand, the fuel collision plate 2 having the above valve function.
When 0 is near full opening, which is far away from the upstream opening of the air funnel 7, the distance between the valve body surface 20b and the inner peripheral surface of the upstream opening edge 7a of the air funnel 7 becomes large, and the injected fuel is scattered. As described above, the fuel collision surface 20a of the fuel collision plate 20 is made to correspond to a state close to 90 ° in the injection port direction of the first fuel injector 9 as described above so that scattering of reflected fuel does not occur and collision is caused by collision. The atomized same reflection fuel is placed on a large amount of intake air, passed through a long intake passage length, sufficiently vaporized, and then supplied to the engine combustion chamber 2.

On the other hand, in the fuel collision plate 20, the first fuel injector 9 is further operated during idle operation and light load when the upstream side opening of the air funnel 7 is fully closed and substantially closed as described above. A heater is embedded in a portion where fuel from the vehicle collides with the heating surface 21, and when the operating state thereof is detected, the heater is energized via the power supply line 25 to heat the heating surface 21. It has become.

At the same time, the valve body surface 20b of the fuel collision plate 20 is located on the side of the first fuel injector 9 and has a slit portion for supplying intake air during idling.
In the idling operation state in which the (groove portion) 34 is formed and the upstream opening of the air funnel 7 is fully closed, a predetermined amount of intake air is intensively supplied through the slit portion 34. , The fuel is injected to the heat generating surface 21 through the concentrated introduction air intake portion and efficiently heated and vaporized on the heat generating surface 21 without adhering to the wall surface, and then mixed into the intake air flow passing near the heat generating surface 21. And efficiently supply it to the engine combustion chamber. Therefore, low load, such as during idle. The fuel vaporization property in the low rotation speed range is also greatly improved, and the combustion stability is improved. Further, in the same region, the heater heats the fuel collision portion of the fuel collision surface 20a of the fuel collision plate 20, and the vaporization atomization property of the adhered fuel can be improved, so that the fuel supply efficiency is increased and the fuel pressure can be reduced. .

Further, reference numeral 17 is a second fuel injector for injecting fuel to the heating wall surface 3a in the intake port 3 before the intake valve 4, and the second fuel injector 17 is for the intake port 3. It is attached to the intake manifold attachment portion 5 via a fuel injector attachment portion in which a fitting port 19 of the injection port portion 18 is formed. Then, for example, at the time of high rotation and high load such as during acceleration, the fuel injected from the second fuel injector 17 hits the hot intake port heating wall surface in the vicinity of the intake valve 4 to be rapidly heated and vaporized, and the intake valve 4 The gas is rapidly supplied into the engine combustion chamber 2 in synchronization with the opening of the valve.

As a result, in combination with the action of the first fuel injector 9, the combustion performance and the combustion efficiency are improved as much as possible over the entire operating range of the engine, and particularly, high speed rotation and high speed during acceleration. The output response under load is also improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway cross-sectional view of a fuel injection device for an engine according to an embodiment of the present invention during high load operation.

FIG. 2 is a cross-sectional view of a main part of the apparatus during idle operation.

FIG. 3 is a graph showing the relationship between the accelerator opening and the height of a fuel collision plate of the same device.

FIG. 4 is a graph showing a relationship between an accelerator opening degree of the device and a tilt displacement angle of a fuel collision plate.

[Explanation of symbols]

1 is an engine body, 2 is an engine combustion chamber, 3 is an intake port, 6 is an intake manifold, 7 is an air funnel, 9 is a first fuel injector, 15 is a slide member,
Reference numeral 16 is a soub, 20 is a fuel collision plate, 20a is a fuel collision surface, 20b is a valve body surface 21, a heat generating surface, and 34 is a slit portion.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area F02M 69/04 P 7825-3G

Claims (5)

[Claims] 1. A fuel collision plate for colliding injected fuel with an intake passage, and a fuel injector for injecting fuel in the intake upstream direction from a downstream side of the fuel collision plate toward a fuel collision surface of the fuel collision plate. In the fuel injection device for an engine, the fuel collision plate is disposed in the air funnel portion upstream of the intake passage, and a drive mechanism for driving the fuel collision plate is provided. The drive mechanism causes the fuel collision plate to open the funnel opening. A fuel injection device for an engine characterized in that the intake air amount can be adjusted by driving in response to changes in the accelerator opening to open and close. 2. The fuel collision plate is configured to be tiltable in association with driving by the drive mechanism, and is tilted in a direction facing a fuel injector as the fuel collision plate becomes farther from a funnel opening of an air funnel portion. The fuel injection device for an engine according to claim 1, wherein: 3. The fuel collision plate is configured to fully close a funnel opening of the air funnel portion, and intake air is supplied through a groove portion formed in the fuel collision plate in the fully closed state. The fuel injection device for an engine according to claim 1 or 2, wherein 4. The fuel injection device for an engine according to claim 3, wherein the groove is formed on the fuel injector side. 5. The fuel collision plate is provided with a heat generating surface for heating the fuel at a portion where fuel collides in the funnel opening fully closed state or a state close to the fully closed state. 4. The engine fuel injection device according to item 4.