JPH09228931A - Intake device for internal combustion engine - Google Patents

Abstract

(57) Abstract: In an intake system for an internal combustion engine in which intake air is guided around fuel injected from an injector, atomization of fuel spray is aimed at. SOLUTION: A first assist air nozzle 21 and a second assist air nozzle 22 for guiding intake air so as to collide with fuel injected from a fuel nozzle of an injector 3 are provided, and a first assist air nozzle 21 for the fuel nozzle is provided. The distances of the second assist air nozzles 22 are different from each other, and the first assist air nozzle 21 and the second assist air nozzle 22 are arranged so that the center line of the fuel nozzle is sandwiched between them.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an improvement of an intake system for an internal combustion engine.

[0002]

2. Description of the Related Art There has been an intake system in which assist air, which is a part of intake air, is applied to fuel injected from an injector into an intake passage to promote atomization of fuel drawn into a cylinder.

As an intake system for an internal combustion engine, there is a conventional one as shown in FIG. 9 (see Japanese Patent Laid-Open No. 5-10224).

The fuel spray ejected from the injector is
As shown by the black arrow in the figure, it is guided to the intake passage through the guide passage 103.

Two assist air injection ports 101 and 102 are opened in the guide passage 103. Assist air nozzle 10
1, 102 communicate with an intake passage upstream of a throttle valve (not shown) via a pipe. Due to the pressure difference generated before and after the throttle valve, the assist air guided by bypassing the throttle valve 10
It spouts from 1, 102 as shown by the outline arrow in the figure.

The assist air ejected from the assist air ejection ports 101 and 102 collides with the fuel injected from the injector to atomize the fuel.

Each of the assist air injection ports 101 and 102 is formed so as to face each other with the guide passage 103 interposed therebetween.

[0008]

However, in such a conventional intake system for an internal combustion engine, since the assist air injection ports 101, 102 face each other at the same position with the guide passage 103 interposed therebetween, the guide air In the passage 103, the airflows passing through the assist air injection ports 101 and 102 collide with each other to cause stagnation, which causes a problem that the atomization of the fuel spray is not sufficiently performed.

An object of the present invention is to solve the above problems and to atomize the fuel spray in an intake system for an internal combustion engine in which intake air is guided around the fuel injected from an injector.

[0010]

An intake system for an internal combustion engine according to a first aspect of the invention is provided with an injector for injecting fuel into an intake passage, and intake air is made to collide with fuel injected from a fuel injection port of the injector. The first assist air nozzle and the second assist air nozzle are provided, and the distances of the first assist air nozzle and the second assist air nozzle to the fuel nozzle are different from each other, and the first assist air nozzle and the second assist air nozzle are both It is arranged so that the center line of the fuel injection port is sandwiched between.

According to a second aspect of the present invention, there is provided an intake system for an internal combustion engine.
In the invention of claim 1, the fuel injection port faces the upper part of the intake passage, the first assist air injection port is arranged below the center line of the fuel injection port, and the second assist air injection port is extracted from the center line of the fuel injection port. Place it above.

According to a third aspect of the present invention, there is provided an intake device for an internal combustion engine.
In the invention according to claim 1 or 2, an intake flow control valve that throttles the intake passage according to operating conditions, and a guide passage that guides fuel injected from an injector to an intake passage downstream of the intake flow control valve, A first assist air injection port and a second assist air injection port that connect the intake passage upstream of the intake flow control valve and the guide passage are provided.

According to a fourth aspect of the present invention, there is provided an intake device for an internal combustion engine.
In the invention according to claim 1 or 2, an intake flow control valve that throttles the intake passage according to operating conditions, and an air supply chamber that is recessed with respect to an intake passage wall upstream from the intake flow control valve. A collar that guides fuel injected from the injector through the air supply chamber to the intake passage downstream of the intake flow control valve, and a first assist air injection port and a second assist air opening in the collar that faces the air supply chamber. And a nozzle.

According to a fifth aspect of the present invention, there is provided an intake device for an internal combustion engine.
In the invention according to claim 1 or 2, an intake flow control valve that throttles the intake passage according to operating conditions, and an air supply chamber that is recessed with respect to an intake passage wall upstream from the intake flow control valve. A partition plate facing the outer periphery of the intake flow control valve in the fully closed position to define the air supply chamber, and fuel injected from the injector passes through the air supply chamber and the partition plate and is downstream of the intake flow control valve. And a first assist air injection port and a second assist air injection port, which face the air supply chamber and are opened in the color.

According to a sixth aspect of the present invention, there is provided an intake system for an internal combustion engine.
In the invention according to claim 4 or 5, the collar is formed in a tubular shape, and the guide tubular portion that defines the assist air injection port is formed in a tubular shape.

[0016] The intake device for an internal combustion engine according to claim 7 is
The invention according to claim 4 or 5, wherein the collar is formed in a columnar shape, a fuel spray passage through which fuel injected from an injector is passed is formed in the collar, and an assist air injection port connecting the air supply chamber and the fuel spray passage is formed in the collar. Is formed into a port shape. According to an eighth aspect of the present invention, in the intake system for an internal combustion engine according to any one of the fourth to seventh aspects, a tip guide portion for fitting a proximal end side inner peripheral surface of the collar to the injector is formed. A flange that is sandwiched between the injector and the intake passage wall is formed at the base end of the collar.

An intake device for an internal combustion engine according to claim 9 is
In the invention according to claim 8, a mounting seat that engages with the flange is formed in the intake passage wall, and the flange and the mounting seat are eccentric with respect to the tip guide portion of the injector.

An intake system for an internal combustion engine according to a tenth aspect of the present invention is the intake system for an internal combustion engine according to any one of the fourth to ninth aspects, wherein an annular shape is fitted in a hole of an intake passage wall at a tip portion of the collar. Form a protrusion.

An intake system for an internal combustion engine according to an eleventh aspect of the present invention is the intake system for an internal combustion engine according to any one of the fourth to tenth aspects, wherein the base end of the collar is sandwiched between an injector and an intake passage wall. A flange is formed, and a sealing material that joins at least one of the injector and the intake passage wall is joined to the flange portion.

[0020]

In the intake system for an internal combustion engine according to claim 1, in the operating state in which the intake flow control valve is closed, the intake air flows into the first assist air injection port and the second assist air injection port by the pressure difference generated before and after the intake flow control valve. It collides with the fuel spray injected from the injector through the assist air injection port.

The intake air flows ejected from the first assist air injection port and the second assist air injection port have different distances from the fuel injection port of the injector, and flow in so as to sandwich the center line of the fuel injection port. The intake air flow ejected from the first assist air injection port and the second assist air injection port collides with the fuel spray injected from the injector from the opposite direction in order, so that the fine particles of the fuel spray do not collide with each other and form a stagnation. Enabled effectively.

As a result, the ignitability of the air-fuel mixture and the stability of flame propagation in the combustion chamber are improved, the ignition timing can be retarded during the cold to dilute the air-fuel ratio, and the exhaust temperature can be increased. Unburned H
The discharge amount of C can be significantly reduced.

In the intake system for an internal combustion engine according to a second aspect of the present invention, the intake air ejected from the first assist air injection port is ejected upward from the lower part of the fuel spray injected from the injector. Therefore, the fuel spray injected from the injector collides with the intake air flow ejected from the first assist air injection port to be atomized and is deflected upward.

The intake air ejected from the second assist air ejection port is ejected downward from the upper portion at a position apart from the first assist air ejection port with respect to the fuel spray injected from the injector. Therefore, the fuel spray injected from the injector collides with the intake air flow ejected from the second assist air injection port to be atomized and is deflected downward.

The fuel spray injected from the injector to the upper part of the intake passage is apt to adhere to the upper part of the intake passage wall near the injector, but the fuel spray downwardly moves away from the intake passage wall by the intake flow ejected from the second assist air injection port. Therefore, the fuel spray is prevented from adhering to the wall of the intake passage and forming a wall flow.

In order to prevent the fuel wall flow from adhering to the wall of the intake passage in this way, the control response of the air-fuel ratio of the air-fuel mixture supplied to the combustion chamber is improved during the transition when the fuel injection amount changes. As a result, the purification rate of the exhaust gas by the three-way catalyst can be maintained, and the emission amount of NOx, HC, etc. can be suppressed.

In the intake system for an internal combustion engine according to a third aspect of the present invention, in the operating state in which the intake flow control valve is closed, the pressure difference generated before and after the intake flow control valve causes the intake air to reach the first assist air nozzle and the second assist air injection port. The fuel injected from the injector through the assist air injection port to the guide passage is atomized.

The intake air flow jetted into the guide passage through the first assist air jet port and the second assist air jet port has different distances from the fuel jet port and flows in so as to sandwich the center line of the fuel jet port. Therefore, the intake air flow ejected from the first assist air nozzle and the second assist air nozzle collides with the fuel spray injected from the injector in order from the opposite direction, and atomizes the fuel spray effectively.

Further, in an operating state in which the intake flow control valve is closed, most of the intake air is guided through the guide passage and passed through the intake port to obtain a rectifying action, which suppresses the spread of the fuel spray and transports it to the combustion chamber. The spray is prevented from adhering to the wall of the intake passage to form a wall flow.

In the intake system for an internal combustion engine according to claim 4, in the operating state in which the intake flow control valve is closed, the first intake air passes through the air supply chamber due to the pressure difference generated before and after the intake flow control valve. , A jet from the second assist air jet into the collar. The high-speed intake air flow jetted from the first and second assist air jets collides with the fuel passing through the collar to promote atomization of the fuel.

In the intake system for an internal combustion engine according to a fifth aspect of the present invention, the air supply chamber is defined by a partition plate facing the outer peripheral portion of the intake flow control valve in the fully closed position. The opening area for the intake passage can be increased to smooth the flow of intake air.

In the intake system for an internal combustion engine according to claim 6, in the operating state in which the intake flow control valve is closed, the intake air is injected from the air supply chamber through the first and second assist air injection ports into the inside of the collar. The flow is guided by the guide tube portion and flows in from a predetermined direction with respect to the collar, so that atomization of the fuel can be promoted.

In the intake system for an internal combustion engine according to claim 7, in the operating state in which the intake flow control valve is closed, the intake air ejected from the air supply chamber through the first and second assist air nozzles into the collar. Since the flow is guided by the port-shaped first and second assist air injection ports and flows from a predetermined direction with respect to the collar, atomization of the fuel can be promoted.
In the intake device for an internal combustion engine according to the eighth aspect, the collar is positioned with respect to the injector by a structure in which the inner peripheral surface of the collar on the proximal end side is fitted to the tip guide portion of the injector.

When the injector is fastened to the intake passage wall via a bolt or the like, the flange formed at the base end portion of the collar is sandwiched and fixed between the injector and the intake passage wall. As a result, the bolts and the like for fastening the collar to the intake passage wall can be eliminated, and the productivity can be improved.

In the intake system for an internal combustion engine according to the ninth aspect of the present invention, the rotational direction of the collar is changed by the structure in which the tip end guide portion of the injector with which the proximal end inner peripheral surface of the collar is fitted and the mounting seat with which the flange engages are eccentric. Is positioned. As a result, it is possible to eliminate pins and the like that prevent the collar from rotating with respect to the intake passage wall, thereby improving productivity.

In the intake system for an internal combustion engine according to claim 10, before assembling the injector on the intake passage wall,
The annular protrusion formed at the tip of the collar fits into the hole in the wall of the intake passage to prevent the collar from coming off. Therefore, it is possible to unitize these parts with the collar inserted into the intake passage wall,
Increases productivity.

In the intake system for an internal combustion engine according to the eleventh aspect of the invention, a structure is provided in which a flange is provided with a seal member joined to at least one of the injector and the intake passage wall.
Ensuring the sealability of the collar and the mounting portion of the injector with respect to the intake passage wall.

Further, by the structure in which the sealing material is coupled to the flange, the assembling property can be improved and the sealing material can be securely assembled.

[0039]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, two intake ports 4 branch in the middle to open into the combustion chamber 1 and are opened and closed in synchronization with the engine rotation by an intake valve (not shown). As the intake valve is opened, intake air (air mixture) is drawn into the combustion chamber 1 from the intake port 4, compressed by the piston, ignited and burned by the spark plug, and the exhaust valve is opened. Exhaust gas is exhausted to each exhaust port, and each of these steps is continuously repeated.

A throttle valve (not shown) is provided in the intake passage 11 upstream of the intake port 4. The throttle valve opens and closes in conjunction with the accelerator pedal to adjust the intake air amount.

An injector 3 facing the intake port 4 is attached to the intake passage wall 10. The injector 3 is driven to open by a drive pulse signal output from a control device (not shown), and injects fuel adjusted to a predetermined pressure.

An intake air flow control valve 8 is provided downstream of the throttle valve in the intake passage 11. The intake flow control valve 8 is rotationally driven by an actuator from a fully open position substantially parallel to the passage centerline of the intake passage 11 to a fully closed position substantially orthogonal to the passage centerline of the intake passage 11.

A control device (not shown) controls the intake flow control valve 8 to be closed in a predetermined low speed and low load region in accordance with the contents of a map preset according to the operating state of the engine.

A guide passage 12 facing the injector 3 is formed in the intake passage wall 10. The guide passage 12 is located on the downstream side of the intake flow control valve 8 and opens above the intake passage wall surface 13. The guide passage 12 defines a space through which the fuel spray injected from the injector 3 passes.

A first assist air nozzle 21 and a second assist air nozzle 22 are formed which connect the guide passage 12 and the intake passage 11 upstream of the intake flow control valve 8. That is, the first assist air nozzle 21 and the second assist air nozzle 22 constitute a bypass passage that bypasses the intake flow control valve 8 and guides intake air.

The first assist air injection port 21 and the second assist air injection port 22 open into the guide passage 12 at different distances L1 and L2 from the fuel injection port of the injector 3. The first assist air injection port 21 is closer to the fuel injection port of the injector 3 than the second assist air injection port 22.

The first assist air injection port 21 and the second assist air injection port 22 are arranged so that the center line of the fuel injection port of the injector 3 is sandwiched between them. The first assist air injection port 21 opens at the lower part of the guide passage 12, and the second assist air injection port 22 opens at the upper part of the guide passage 12.

The center line of the fuel injection port of the injector 3 extends toward the opening of the intake port 4 with respect to the combustion chamber 1. The center lines of the first assist air injection port 21 and the second assist air injection port 22 are arranged on a plane including the center line of the fuel injection port of the injector 3. The first assist air injection port 21 and the second assist air injection port 22 are inclined toward the downstream side of the guide passage 12.

With the above construction, the operation will be described below.

In the operating state in which the intake flow control valve 8 is opened, the intake flow control valve 8 does not restrict the flow of intake air, and the fuel spray injected from the injector 3 through the guide passage 12 mixes with air. While being sucked into the combustion chamber 1, the air-fuel mixture is made uniform.

In the operating state in which the intake flow control valve 8 is closed, the pressure difference generated before and after the intake flow control valve 8 causes
Most of the intake air is ejected into the guide passage 12 through the first assist air injection port 21 and the second assist air injection port 22 as shown by arrows in the figure, and atomization of the fuel injected from the injector 3 is achieved.

That is, the intake air jetted from the first assist air jet port 21 into the guide passage 12 is jetted upward from the lower surface of the guide passage 12 in the vicinity of the injector 3.
Therefore, the fuel spray injected from the injector 3 is
It collides with the intake air flow ejected from the first assist air ejection port 21 to generate atomization and is deflected upward.

The intake air jetted from the second assist air jet port 22 to the guide passage 12 is jetted downward from the upper surface of the guide passage 12 at a position apart from the first assist air jet port 21 with respect to the injector 3. Therefore, the fuel spray injected from the injector 3 collides with the intake air flow ejected from the second assist air injection port 22 to be atomized and is deflected downward.

In this way, the high-speed intake air flows ejected from the first assist air injection port 21 and the second assist air injection port 22 sequentially collide with the fuel spray passing through the guide passage 22 from opposite directions, thereby colliding with each other and stagnant. Atomization of fuel is promoted without producing. As a result, the ignitability of the air-fuel mixture in the combustion chamber 1 and the stability of flame propagation are improved, and it becomes possible to retard the ignition timing and to dilute the air-fuel ratio when cold, and to raise the exhaust temperature to increase the catalyst temperature. The temperature rise time can be shortened and the amount of unburned HC discharged can be greatly reduced.

In addition, from the injector 3 to the intake passage wall 13
The fuel spray injected into the upper portion of the intake port 4 through the guide passage 12 facing the upper portion of the fuel is likely to adhere to the upper portion of the intake passage wall 13 close to the injector 3, but the fuel spray opened to the upper portion of the guide passage 12 on the outlet side. Since the intake air flow ejected from the second assist air injection port 22 is deflected downward so as to move away from the intake passage wall 13, the fuel spray is prevented from adhering to the intake passage wall and forming a wall flow.

Furthermore, in the operating state in which the intake flow control valve 8 is closed, most of the intake air passes through the guide passage 12 and the intake port 4, so that the guide spray passage 12 rectifies the intake air to spread the fuel spray. It can be suppressed and transported to the combustion chamber 1.

In this way, it is possible to prevent the wall flow of the fuel from adhering to the intake passage wall 26, so that the control responsiveness to the air-fuel ratio of the air-fuel mixture supplied to the combustion chamber is improved at the transition when the fuel injection amount changes. To do. As a result, the exhaust gas purification rate by the three-way catalyst (not shown) is maintained, and the emission amount of NOx, HC and the like can be suppressed.

The first assist air injection port 2 is formed in the intake passage wall 10.
1, because of the structure forming the second assist air nozzle 22,
Since it is not necessary to provide the injector 3 with the assist air injection port, the productivity can be improved.

Next, another embodiment shown in FIG. 2 will be described. The parts corresponding to those in FIG. 1 are designated by the same reference numerals.

A collar 30 through which the fuel spray injected from the injector 3 passes is provided. The collar 30 has a cylindrical shape.

An air supply chamber 16 which is recessed in the intake passage wall surface 13 is formed. The air supply chamber 16 has an intake flow control valve 8
The space open to the intake passage 11 on the upstream side is provided with a collar 30.
To define around.

The partition wall 17 which defines the air supply chamber 16 is formed so as to face the outer peripheral portion of the intake flow control valve 8 in the valve closed position.

In the cylindrical collar 30, the first assist air nozzle 31 and the second assist air nozzle 32 are provided in the air supply chamber 16.
Formed facing the. That is, the first assist air injection port 31 and the second assist air injection port 32 are connected to the intake flow control valve 8
A bypass passage is constructed to bypass the intake air and guide the intake air.

The first assist air injection port 31 and the second assist air injection port 32 open into the collar 30 at different distances from the fuel injection port of the injector 3. The first assist air injection port 31 is closer to the fuel injection port of the injector 3 than the second assist air injection port 32.

The first assist air injection port 31 and the second assist air injection port 32 are arranged such that the center line of the fuel injection port of the injector 3 is sandwiched between them. The first assist air injection port 31 opens at the bottom of the collar 30, and the second assist air injection port 32 opens at the top of the collar 30.

The injector 3 has a columnar end guide portion 36 having a fuel injection opening. Tip guide part 36
The inner peripheral surface of the base end side of the collar 30 is fitted to the. This allows
The collar 30 is positioned with respect to the injector 3.

A flange 35 is formed at the base end of the cylindrical collar 30. By fastening the injector 3 to the intake passage wall 10 via a bolt (not shown), the flange 35 is sandwiched between the injector 3 and the mounting seat 24 formed on the intake passage wall 10.

As shown in FIG. 3, in the cylindrical collar 30, guide cylinders 37 and 38 defining a first assist air nozzle 31 and a second assist air nozzle 32 are formed into a cylindrical shape by press working. To be done.

The operation will be described below.

In the operating state in which the intake flow control valve 8 is closed, the pressure difference generated before and after the intake flow control valve 8 causes
Intake air passes through the air supply chamber 16 and is jetted into the collar 30 from the first assist air jet port 31 and the second assist air jet port 32.

The intake air flow ejected from the first assist air injection port 31 and the second assist air injection port 32 inside the collar 30 collides with the fuel spray injected from the injector 3 from the opposite direction in order, and atomizes the fuel. Promote.

The fuel spray injected from the injector 3 to the upper portion of the branch portion 12 through the collar 30 easily adheres to the upper portion of the intake passage wall surface 13 near the injector 3, but the second assist opening on the upper portion of the collar 30 is used. The intake air flow ejected from the air injection port 32 is deflected away from the intake passage wall 13 to prevent the fuel spray from adhering to the intake passage wall 13 and forming a wall flow.

The partition wall 17 that defines the air supply chamber 16 faces the outer peripheral portion of the intake flow control valve 8 in the closed position, and the collar 30 that allows the fuel from the injector 3 to pass through is separated by the partition wall 1.
The structure provided through 7 allows the front and rear of the intake flow control valve 8 to be communicated with each other by the first assist air injection port 31 and the second assist air injection port 32 opened in the collar 30.

Since the intake air bypassing the intake flow control valve 8 is guided by the first assist air injection port 31 and the second assist air injection port 32, elongate holes formed in the external pipe or the intake passage wall 10 are required. And the structure can be simplified.

Since the first assist air nozzle 31 and the second assist air nozzle 32 are formed in the collar 30, the specifications of the engine can be changed by changing the opening diameters of the first assist air nozzle 31 and the second assist air nozzle 32. It becomes easier to deal with and productivity can be improved.

Next, another embodiment shown in FIG. 4 will be described. The parts corresponding to those in FIG. 2 and the like are designated by the same reference numerals.

The flange 35 is formed offset from the collar 30 by a predetermined value L3. As a result, the width of the flange 35 changes in the circumferential direction.

The mounting seat 24 for the flange 35 of the intake passage wall is also formed offset from the collar 30 by a predetermined value L.

In this case, the collar 30 has its flange 35
Is sandwiched between the injector and the mounting seat 24 formed on the wall of the intake passage, and is coupled.
Due to the structure in which the fitting hole is eccentric midway, the collar 30 is positioned in the rotational direction with respect to the intake passage wall.

Next, another embodiment shown in FIG. 5 will be described.

The resin collar 40 is formed in a cylindrical shape.

The collar 40 has a first assist air injection port 41.
The second assist air injection port 42 is formed in a port shape.
That is, the first assist air ejection port 41 and the second assist air ejection port 42 define a space having a right cylindrical shape.

The first assist air nozzle 41 and the second assist air nozzle 42 open into the collar 40 at different distances from the fuel nozzle of the injector. The first assist air injection port 41 is closer to the fuel injection port of the injector than the second assist air injection port 42.

The first assist air injection port 41 and the second assist air injection port 42 are arranged such that the center line of the fuel injection port of the injector is sandwiched between them. The first assist air injection port 41 opens at the bottom of the collar 40, and the second assist air injection port 42 opens at the top of the collar 40.

The collar 40 is formed with a recess 44 which fits into the tip of the injector, and a conical fuel spray passage 43 through which the fuel injected from the injector passes.

In this case as well, in the operating state in which the intake flow control valve is closed, the intake flow ejected from the first assist air injection port 41 and the second assist air injection port 42 inside the collar 40 is the fuel injected from the injector. It collides with the spray from the opposite direction in order to promote atomization of the fuel.

Next, another embodiment shown in FIG. 6 will be described.

A flange 55 is formed on the base end portion of the collar 50, and an annular protrusion 54 is formed on the tip end portion.

Before the injector is assembled to the intake passage wall, the annular projection 56 is fitted into the hole with a shrink fit while the collar 50 is inserted into the intake passage wall, so that the collar 50 is prevented from coming off. For this reason, the collar 50 can be unitized in a state where it is inserted into the intake passage wall, and the productivity can be improved.

The flange 35 is sandwiched between the injector and the mounting seat 24 formed on the intake passage wall 10 by fastening the injector to the intake passage wall via a bolt (not shown).

Thus, in the state where the collar 50 is assembled to the intake passage wall, the annular protrusion 56 fits into the hole of the intake passage wall without any gap, and the sealing property between the collar 50 and the hole can be improved.

Next, another embodiment shown in FIG. 7 will be described. The parts corresponding to those in FIG. 2 are denoted by the same reference numerals.

A collar 60 through which the fuel spray injected from the injector 3 passes is provided. The collar 60 is formed in a cylindrical shape.

A partition plate 67 is provided around the collar 60 to define an air supply chamber 66 opening to the intake passage 11 on the upstream side of the intake flow control valve 8. .

A partition plate 67 defining the air supply chamber 66 is fixedly attached to the collar 60. The partition plate 67 is arranged so as to face the outer peripheral portion of the intake flow control valve 8 in the valve closed position.

In the cylindrical collar 60, the first assist air nozzle 61 and the second assist air nozzle 62 are provided with an air supply chamber 66.
Formed facing the. That is, the first assist air nozzle 61 and the second assist air nozzle 62 are the intake flow control valve 8
A bypass passage is constructed to bypass the intake air and guide the intake air.

A flange 65 is formed at the base end of the cylindrical collar 60. When the injector 3 is fastened to the intake passage wall 10 via a bolt (not shown), the flange 65 is sandwiched between the injector 3 and the mounting seat 24 formed on the intake passage wall 10.

The flange 65 is joined to the mounting seat 24 and the injector 3 via a sealing material 69 so as to ensure the sealing performance of the collar 60 and the mounting portion of the injector 3. The sealing material 69 is formed in an annular shape with a U-shaped cross section, and is joined so as to wrap both sides of the flange 35.

With the above-mentioned structure, the operation will be described.

In the operating state in which the intake flow control valve 8 is closed, the pressure difference generated before and after the intake flow control valve 8 causes
Intake air passes through the air supply chamber 66 and is ejected from the first assist air ejection port 61 and the second assist air ejection port 62 into the collar 60.

The intake air flow ejected from the first assist air nozzle 61 and the second assist air nozzle 62 inside the collar 60 collides with the fuel spray injected from the injector 3 from the opposite direction in order, and atomizes the fuel. Promote.

A partition plate 67 that defines the air supply chamber 66 faces the outer peripheral portion of the intake flow control valve 8 in the closed position, and the collar 60 that allows the fuel from the injector 3 to pass through is separated by the partition plate 6.
With the structure that penetrates through 7, the first assist air injection port 61 and the second assist air injection port 62 that are opened in the collar 60 can connect the front and rear of the intake flow control valve 8.

By defining the air supply chamber 66 through the partition plate 67 facing the outer peripheral portion of the intake flow control valve 8 in the fully closed position, the opening area of the air supply chamber 66 to the intake passage 11 is increased. As a result, the flow of intake air can be made smooth.

Since the intake air bypassing the intake air flow control valve 8 is guided by the first assist air injection port 61 and the second assist air injection port 62, elongate holes formed in the external pipe or the intake passage wall 10 are required. And the structure can be simplified.

Next, another embodiment shown in FIG. 8 will be described.

The flange 85 of the collar 80 is a sealing material 86.
It is joined to the attachment seat of the wall of the intake passage via the so as to ensure the sealing property of the attachment portion of the collar 80 and the injector.

The sealing material 86 is formed in an annular shape having a circular cross section, and is integrated so as to be wrapped around the lower surface of the flange 85.

With the structure in which the sealing material 86 is integrated with the collar 80 in this manner, the assembling property can be improved, and the sealing material 86 can be securely assembled.

[0110]

As described above, in the intake system for the internal combustion engine according to the first aspect, the intake flow ejected from the first assist air injection port and the second assist air injection port is different from the fuel spray injected from the injector. Since they collide with each other in the opposite directions in sequence, they can promote atomization of the fuel without colliding with each other to form a stagnation, the combustion efficiency can be improved even in the cold state, and the emission amount of unburned HC can be significantly reduced. it can.

The intake system for an internal combustion engine according to claim 2 is
Since the intake air flow ejected from the second assist air jet is deflected downward so as to move away from the intake passage wall, it is possible to prevent the fuel spray from adhering to the intake passage wall to form a wall flow,
The control response of the air-fuel ratio at the time of transition is improved, and NOx,
Emissions of HC etc. can be suppressed.

The intake system for an internal combustion engine according to claim 3 is
By the rectifying action obtained by passing the intake air through the intake passage through the intake port, the spread of the fuel spray is suppressed and transported to the combustion chamber, and the fuel spray is prevented from adhering to the wall of the intake passage and forming a wall flow.

The intake system for an internal combustion engine according to claim 4 is
Due to the structure in which the collar that allows the fuel from the injector to pass through is provided, it becomes possible to define the spray processing passage that leads the intake air that bypasses the intake flow control valve through the collar, and the length that is formed in the external pipe or the intake passage wall There is no need for holes and the like, the structure is simplified, and the cost of the product is reduced.

The intake system for an internal combustion engine according to claim 5 is
By defining the air supply chamber through the partition plate facing the outer peripheral portion of the intake flow control valve in the fully closed position, the opening area of the air supply chamber to the intake passage is increased and the flow of intake air is made smooth. can do.

The intake system for an internal combustion engine according to claim 6 is
In the operating state in which the intake flow control valve is closed, the intake flow ejected from the air supply chamber to the inside of the collar through the first and second assist air injection ports is guided by the guide cylinder part and flows in from the predetermined direction with respect to the collar. To promote atomization of fuel,
Flammability can be increased.

The intake system for an internal combustion engine according to claim 7 is:
In the operating state where the intake flow control valve is closed, the intake flow ejected from the air supply chamber to the inside of the collar through the first and second assist air injection ports is guided to the port-shaped first and second assist air injection ports. As a result, the fuel flows from a predetermined direction with respect to the collar, so that atomization of the fuel can be promoted and the combustibility can be enhanced.

The intake system for an internal combustion engine according to claim 8 is
The collar is positioned with respect to the injector by the structure in which the inner peripheral surface of the collar on the proximal end side is fitted to the tip guide portion of the injector, and the structure can be simplified without the need for bolts for fastening the collar.

The intake system for an internal combustion engine according to claim 9 is
Due to the eccentric structure of the mounting seat that engages the flange of the injector and the guide part of the injector that fits the inner peripheral surface of the base of the collar, positioning is performed in the rotational direction of the collar, and rotation of the collar with respect to the intake passage wall is prevented. It is possible to eliminate pins and the like, which simplifies the structure.

In the intake system for an internal combustion engine according to a tenth aspect of the present invention, before the injector is assembled to the intake passage wall, the annular protrusion formed at the tip of the collar is fitted into the hole of the intake passage wall. Since the collar is prevented from coming off, these parts can be unitized and productivity can be improved.

In the intake system for the internal combustion engine according to the eleventh aspect of the present invention, the assembling property of the collar to the intake passage wall is improved by the structure in which the flange is provided with the seal member joined to at least one of the injector and the intake passage wall. With
Assembling of the sealing material can be reliably performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment of the present invention.

FIG. 2 is a sectional view showing another embodiment.

FIG. 3 is a sectional view of the collar.

FIG. 4 is a front view of a collar showing still another embodiment.

FIG. 5 is a sectional view of a collar showing still another embodiment.

FIG. 6 is a side view of a collar showing still another embodiment.

FIG. 7 is a sectional view showing still another embodiment.

FIG. 8 is a sectional view of a collar showing still another embodiment.

FIG. 9 is a sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustion chamber 3 Injector 4 Intake port 8 Intake flow control valve 10 Intake passage wall 11 Intake passage 12 Guide passage 13 Intake passage wall surface 16 Air supply chamber 17 Partition wall 21 First assist air nozzle 22 Second assist air nozzle 24 Mounting seat 30 Color 31 First assist air nozzle 32 Second assist air nozzle 35 Flange 36 Tip guide section 60 Color 61 First assist air nozzle 62 Second assist air nozzle 65 Flange 66 Air supply chamber 67 Partition plate 69 Sealing material

Claims (11)

[Claims] 1. An injector for injecting fuel into an intake passage, comprising a first assist air nozzle and a second assist air nozzle for guiding intake air so as to collide with fuel injected from a fuel nozzle of the injector, The distance between the first assist air nozzle and the second assist air nozzle is different from each other, and the first assist air nozzle and the second assist air nozzle are arranged so that the center line of the fuel nozzle is sandwiched between them. An intake device for an internal combustion engine that features. 2. The fuel injection port faces the upper part of the intake passage, the first assist air injection port is arranged below the center line of the fuel injection port, and the second assist air injection port is arranged above the center line of the fuel injection port. The intake system for an internal combustion engine according to claim 1, wherein: 3. An intake flow control valve for narrowing the intake passage according to operating conditions, a guide passage for guiding fuel injected from an injector to an intake passage downstream of the intake flow control valve, and an upstream of the intake flow control valve. 3. The intake device for an internal combustion engine according to claim 1, further comprising: a first assist air injection port and a second assist air injection port that communicate the side intake passage and the guide passage. 4. An intake flow control valve that throttles the intake passage according to operating conditions, an air supply chamber that is recessed in a wall of the intake passage upstream of the intake flow control valve, and fuel injected from an injector. A collar that penetrates the air supply chamber to the intake passage downstream of the intake flow control valve, and a first assist air nozzle and a second assist air nozzle that face the air supply chamber and open in the collar. The intake system for an internal combustion engine according to claim 1 or 2, wherein. 5. An intake flow control valve that throttles the intake passage according to operating conditions, an air supply chamber that is recessed with respect to an intake passage wall upstream of the intake flow control valve, and an intake air at a fully closed position. A partition plate facing the outer periphery of the flow control valve to define the air supply chamber, and fuel injected from the injector penetrates the air supply chamber and the partition plate and is guided to the intake passage downstream of the intake flow control valve. The intake device for an internal combustion engine according to claim 1 or 2, further comprising: a collar; and a first assist air injection port and a second assist air injection port that face the air supply chamber and are opened in the collar. 6. The collar according to claim 4, wherein the collar is formed in a tubular shape, and a guide tubular portion that defines the first and second assist air jets is formed in the collar. Intake device for internal combustion engine. 7. The collar is formed in a columnar shape, a fuel spray passage through which fuel injected from an injector is passed is formed in the collar, and first and second assist air nozzles connecting the air supply chamber and the fuel spray passage are formed in the collar. The intake device for an internal combustion engine according to claim 4, wherein the intake device is formed in a port shape. 8. A front end guide portion for fitting the inner peripheral surface of the collar on the base end side is formed on the injector, and a flange sandwiched between the injector and the intake passage wall is formed on the base end portion of the collar. The intake system for an internal combustion engine according to claim 4, wherein the intake system is an internal combustion engine. 9. The internal combustion engine according to claim 8, wherein a mounting seat that engages with the flange is formed in the intake passage wall, and the flange and the mounting seat are eccentric with respect to the tip guide portion of the injector. Intake device. 10. The intake air for an internal combustion engine according to claim 4, wherein an annular projection is formed at a front end of the collar so as to be fitted into a hole of an intake passage wall. apparatus. 11. A flange which is sandwiched between an injector and an intake passage wall is formed at a base end portion of the collar, and a sealing material which is joined to at least one of the injector and the intake passage wall is joined to the flange portion. The intake system for an internal combustion engine according to any one of claims 4 to 10.