JPH09166064A - Air intake device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a wall flow caused by sticking of fuel injected from an injector to an intakes air passage wall in the air intake device of an internal combustion engine. SOLUTION: An air supply room 36 communicated to an intake air passage 11 located in an upstream side more than an intakes air flow control valve 8 is formed in a cylinder head 10, a water jacket 5 for circulating cooling water to the vicinity of the air supply room 36 is formed in the cylinder head 10, a collar 20 for guiding fuel injected from an injector 3 through the air supply room 36 and a partition wall 37 to an air intake port 4 located in the more downstream side than the intake air flow control valve 8 is provided and an air curtain injection part 18 for communicating the air supply room 36 through the collar 20 with the air intake port 4 located in the more downstream side than the intake air flow control valve 8 is provided.

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 In an engine in which fuel injected from an injector into an intake passage is mixed with intake air and sucked into a combustion chamber, the fuel injected from the injector does not adhere to the wall of the intake passage to form a wall flow. Required to.

FIG. 30 shows a conventional intake system for an internal combustion engine.
(See Japanese Utility Model Application Laid-Open No. 57-49570).

One end of the assist air passage 104 opens near the fuel injection port of the injector 103. The other end of the assist air passage 104 communicates with an intake passage 101 upstream of a throttle valve (not shown) via a pipe 105 or the like.

Due to the pressure difference generated before and after the throttle valve, part of the intake air (auxiliary air) is assisted by the assist air passage 10.
4 is guided to the fuel injected from the injector 103 through 4 and is atomized into the cylinder to promote atomization.

An annular nozzle 106 is provided in front of the injector 103. A fuel injection port 107 is formed in the center of the nozzle 106, and a plurality of assist air injection ports 108 are formed in parallel with each other around the fuel injection port 107.

A part of the intake air is jetted from each assist air injection port 108 so as to surround the outer periphery of the injected fuel, and the fuel spray adheres to the upper part of the intake passage wall located in front of the injector 103. To prevent a wall flow.

[0008]

However, in such a conventional intake system for an internal combustion engine, it is necessary to dispose the pipe 105 defining the assist air passage 104 outside the intake manifold 109. There is a problem that the number of parts increases and the structure becomes complicated.

Further, in the one disclosed in Japanese Utility Model Laid-Open No. 61-80365, the assist air passage is formed in the intake manifold, and piping or the like is unnecessary.

However, in this case, since the assist air passage has a structure defined by a long hole formed in the intake manifold by drilling, there is a problem that the number of machining steps is increased and the productivity is poor.

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

[0012]

An intake system for an internal combustion engine according to a first aspect of the present invention is a butterfly type intake system in which an intake port for guiding intake air to a combustion chamber is formed in a cylinder head, and an intake passage is throttled according to operating conditions. A flow control valve is provided, an air supply chamber that communicates with the intake passage upstream of the intake flow control valve is formed in the cylinder head, and a partition wall that defines the air supply chamber is formed in the cylinder head. A water jacket that circulates cooling water is formed in the cylinder head, an injector that injects fuel is attached to the cylinder head, and fuel injected from the injector penetrates the air supply chamber and the partition wall and is downstream of the intake flow control valve. And a collar that leads to the intake passage, and defines a spray processing passage that connects the air supply chamber to the intake port on the downstream side of the intake flow control valve via the collar.

An intake system for an internal combustion engine according to claim 2 is
In the invention according to claim 1, a branch portion for guiding intake air to the intake port is formed in the intake manifold,
A butterfly-type intake flow control valve that throttles the branch section according to operating conditions is installed in the intake manifold, and a sub-port that connects the branch section upstream of the intake flow control valve and the air supply chamber is formed by casting in the intake manifold. To do.

The intake system for an internal combustion engine according to claim 3 is
In the invention according to claim 1, a butterfly-type intake flow control valve that throttles the intake port according to operating conditions is provided in a cylinder head, and the intake flow control valve is formed in a concave shape with respect to an intake passage wall upstream from the intake flow control valve. A recessed air supply chamber is defined in the cylinder head, and a partition wall defining the air supply chamber is formed so as to face the outer peripheral portion of the intake flow control valve in the valve closed position.

An intake system for an internal combustion engine according to claim 4 is
In the invention according to claim 3, the air supply chamber is recessed so that its cross-sectional area expands toward the branch portion.

The intake system for an internal combustion engine according to claim 5 is
In the invention according to any one of claims 1 to 4,
An air curtain nozzle is defined between the collar and a hole through which the collar penetrates as a spraying passage.

The intake system for an internal combustion engine according to claim 6 is
In the invention according to claim 5, the collar is made to face the upper part of the intake passage, and the air curtain injection port is opened only at the upper part of the collar.

The intake system for an internal combustion engine according to claim 7 is:
In the invention according to any one of claims 1 to 4,
As the spray processing passage, an assist air jet opening that faces the air supply chamber is formed in the collar.

An intake system for an internal combustion engine according to claim 8 is
In the invention according to claim 7, the collar is formed in a tubular shape, and the guide tubular portion that defines the assist air ejection port is formed in the tubular shape.

An intake system for an internal combustion engine according to claim 9 is
In the invention according to claim 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 an assist air injection port connecting the air supply chamber and the fuel spray passage is formed in the collar. Form.

According to a tenth aspect of the invention, in the intake system for an internal combustion engine according to the eighth or ninth aspect of the invention, the plurality of assist air injection ports are opened so as to face each other inside the collar.

According to an eleventh aspect of the present invention, in the intake system for an internal combustion engine according to any one of the first to tenth aspects, a tip guide portion for fitting the inner peripheral surface of the base of the collar to the injector is provided. And a flange that is sandwiched between the injector and the intake manifold is formed at the base end of the collar.

According to a twelfth aspect of the present invention, in the intake system for an internal combustion engine according to the eleventh aspect of the present invention, a mounting seat that engages with a flange is formed in the intake manifold,
Make the flange and mounting seat eccentric with respect to the tip guide of the injector.

According to a thirteenth aspect of the present invention, in the intake system for an internal combustion engine according to any one of the first to twelfth aspects of the present invention, an annular projection is fitted at the tip of the collar into a hole of the intake manifold. To form a part.

An intake system for an internal combustion engine according to a fourteenth aspect is the invention according to any one of the first to thirteenth aspects, wherein a flange is held at a base end portion of the collar between an injector and an intake manifold. Is formed, and a sealing material that joins at least one of the injector and the intake manifold is joined to the flange portion.

An intake system for an internal combustion engine according to a fifteenth aspect of the present invention is the invention according to any one of the first to tenth aspects, wherein the collar is provided with a protector portion to be fitted with an ejector.

According to a sixteenth aspect of the present invention, in the intake system for an internal combustion engine according to any one of the first to fifteenth aspects, an opening for an intake passage of the air supply chamber is provided in front of and behind the intake flow control valve. An on-off valve that opens due to the pressure difference that occurs is provided.

[0028]

In the intake system for an internal combustion engine according to claim 1, in the operation state in which the intake flow control valve is closed, the intake air passes through the air supply chamber and is sprayed by the pressure difference generated before and after the intake flow control valve. Eject from the passage.

The intake flow ejected from the spray processing passage promotes atomization of the fuel spray ejected from the collar to the intake passage and diffused, and prevents the fuel spray from adhering to the intake passage wall to form a wall flow. .

The intake air flowing from the air supply chamber to the intake port through the spray machining passage is heated by heat transfer from the cooling water circulating in the water jacket provided in the vicinity of the intake air, and is jetted to the intake port via the collar. Fuel vaporization is promoted.

Due to the structure in which the collar for passing the fuel from the injector is provided through the air supply chamber and the partition wall,
It is possible to define a spray processing passage that guides intake air that bypasses the intake flow control valve via a collar, and does not require external piping or elongated holes formed by machining, simplifying the structure. Be peeled off.

In the intake system for an internal combustion engine according to a second aspect of the present invention, in the operating state in which the intake flow control valve interposed in the branch portion is closed, the intake air is branched due to a pressure difference generated before and after the intake flow control valve. Flow through the auxiliary port and the air supply chamber to the spray processing passage.

The sub-port can be integrally formed when the intake manifold is cast, and the air supply chamber can be integrally formed when the cylinder head is cast, which improves productivity.

In the intake system for an internal combustion engine according to a third aspect of the present invention, when the intake flow control valve interposed in the intake port is closed, the intake air is sucked by a pressure difference generated before and after the intake flow control valve. It flows from the port through the air supply chamber to the spray processing passage.

The partition wall defining the air supply chamber faces the outer peripheral portion of the intake flow control valve in the closed position, and the collar for passing the fuel from the injector is provided through the partition wall. It is possible to define a spray machining passage that guides intake air that bypasses the intake air flow control valve, and there is no need for external pipes or elongated holes formed by machining, which simplifies the structure. .

The air supply chamber can be integrally formed at the time of casting the cylinder head, and the productivity can be improved.

In the intake system for an internal combustion engine according to a fourth aspect, since the air supply chamber has a structure in which it is recessed in a taper shape with respect to the intake passage wall of the intake port, the intake port of the core is not opened during casting of the cylinder head. It is not necessary to mold the molding part and the air supply chamber molding part by separate molds. That is, when the branch portion is curved in the vertical direction, it is possible to form a core in which a portion for forming the branch portion and a portion for forming the air supply chamber are integrated by using a mold that is divided into upper and lower parts.
Increases productivity.

In the intake system for an internal combustion engine according to claim 5, 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 pass through the air supply chamber and the air curtain. Eject around the collar from the nozzle.

The intake flow jetted from the air curtain jet port is
It encloses the fuel spray that is jetted from the collar to the intake passage and diffuses, and prevents the fuel spray from adhering to the wall of the intake passage and forming a wall flow. Further, even if a wall flow of the fuel once occurs in the intake passage wall, the fuel is separated from the intake passage wall by the high-speed intake flow ejected from the air curtain injection port.

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 at 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 claim 6, the operation in which the intake flow control valve is closed because the air curtain injection port is open only in the upper part of the collar arranged in the upper part of the intake passage. In this state, the intake air is ejected from the air curtain injection port along the upper part of the intake passage wall through the air supply chamber.

The fuel spray ejected from the collar arranged at the upper part of the intake passage to the upper part of the intake passage wall close to the injector tends to be attached to the intake passage, but is ejected from the air curtain nozzle opening limited to the upper part of the collar. The intake flow that forms forms an air layer between the fuel spray and the intake passage wall, and prevents the fuel spray from adhering to the intake passage wall and forming a wall flow.

Further, since the air curtain nozzle is opened only in the upper part of the collar, the flow velocity of the air ejected from the air curtain nozzle can be increased, and even if the wall flow of the fuel once occurs in the intake passage wall of the intake port, The fuel can be separated from the wall of the intake passage by the high-speed intake air flow ejected from the curtain injection port.

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 flows through the air supply chamber due to the pressure difference generated before and after the intake flow control valve. It spouts from the spout into the collar.

The high-speed intake air flow ejected from the assist air injection port collides with the fuel passing through the collar and promotes atomization of the fuel. Due to the atomization of the fuel, the ignitability of the air-fuel mixture and the stability of flame propagation in the combustion chamber are improved. By increasing the combustion efficiency in this way, it becomes possible to retard the ignition timing during the cold to dilute the air-fuel ratio, raise the exhaust temperature and shorten the temperature rise time of the catalyst, and discharge unburned HC. The amount can be significantly reduced.

In the intake system for an internal combustion engine according to claim 8, in an operating state in which the intake flow control valve is closed, the intake flow ejected from the air supply chamber through the assist air injection port into the collar is a guide cylinder. The atomization of the fuel can be promoted because it is guided by the portion and flows in from a predetermined direction with respect to the collar.

In the intake system for an internal combustion engine according to a ninth aspect, in an operating state in which the intake flow control valve is closed, the intake flow ejected from the air supply chamber through the assist air injection port into the collar has a port-like shape. The atomization of the fuel can be promoted because it is guided by the assisted air injection port and flows from a predetermined direction with respect to the collar.

In the intake system for an internal combustion engine according to the tenth aspect of the present invention, in the operating state in which the intake flow control valve is closed, the intake flow ejected from the air supply chamber through the plurality of assist air injection ports into the collar is: The fuel spray collides with each other so as to sandwich the fuel spray, and promotes atomization of the fuel.

The intake air jetted to the collar through the assist air jet ports facing each other collide with each other in the collar, and the velocity components for deflecting the fuel spray injected from the injector are canceled each other. For this reason, the fuel spray passing through the collar while being collided with the high-speed intake air flow ejected from each assist air ejection port is suppressed from being deflected toward the wall surface of the intake passage, and adheres to the wall surface of the intake passage to form a wall flow. Is prevented.

In the intake system for an internal combustion engine according to the eleventh aspect, the collar is positioned with respect to the injector by the structure in which the inner peripheral surface of the collar on the base end side is fitted into the tip guide portion of the injector.

When the injector is fastened to the cylinder head via bolts or the like, the flange formed at the base end of the collar is clamped and fixed between the injector and the cylinder head. As a result, bolts and the like for fastening the collar to the cylinder head can be eliminated, and productivity can be improved.

In the intake device for an internal combustion engine according to the twelfth aspect of the present invention, the rotational direction of the collar is changed by the structure in which the tip guide portion of the injector with which the base end inner peripheral surface of the collar fits 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 cylinder head, thereby improving productivity.

In the intake system for an internal combustion engine according to the thirteenth aspect, before the injector is assembled to the cylinder head, the annular projection formed at the tip of the collar is fitted into the hole of the cylinder head, so that the collar The retainer is put on. Therefore, these parts can be unitized with the collar inserted in the cylinder head, and the productivity can be improved.

In the intake system for an internal combustion engine according to the fourteenth aspect of the present invention, the structure in which the flange is provided with a seal member that is joined to at least one of the injector and the cylinder head ensures the sealability of the collar and the mounting portion of the injector to the cylinder head. Secure.

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 surely assembled.

In the intake system for an internal combustion engine according to the fifteenth aspect, the collar and the ejector are unitized by the structure in which the collar is assembled to the ejector through the protector portion, and the productivity can be enhanced.

In the intake system for an internal combustion engine according to the sixteenth aspect, in the operating state in which the intake flow control valve is closed, the opening / closing valve is opened and the intake air is supplied by the pressure difference generated before and after the intake flow control valve. It flows through the air chambers.

In the operating state in which the intake flow control valve opens,
The on-off valve closes, and the burnt gas blown back to the branch portion through the intake port can be suppressed from flowing into the collar or the air supply chamber, and deposits can be prevented from accumulating in the air supply chamber or the like.

[0059]

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 and an exhaust port (not shown) are opened in the combustion chamber 1. A valve seat 6 is fitted into an opening of the intake port 4 with respect to the combustion chamber 1, and an intake valve 7 seated on the valve seat 6 opens and closes in synchronization with engine rotation.

As the intake valve 7 is opened, the engine inhales intake air (mixture) from the intake port 4 into the combustion chamber 1, compresses this intake air with a piston, ignites and burns with a spark plug, and exhaust valve The exhaust gas is exhausted to each exhaust port as the valve is opened, and each of these steps is continuously repeated.

An intake manifold 9 is connected to the cylinder head 10. The intake manifold 9 has an intake passage 11 communicating with the combustion chamber 1 via each intake port 4.
Is defined.

A throttle valve (not shown) is provided in the intake passage 11 upstream of the intake manifold 9. The throttle valve opens and closes in conjunction with the accelerator pedal to adjust the intake air amount.

The injector 3 facing the intake port 4 is attached to the cylinder head 10. Fuel is injected from the injector 3 to the intake port 4.

The injector 3 is valve-opened by a drive pulse signal output from a control device (not shown) to inject fuel adjusted to a predetermined pressure.

The intake manifold 9 is provided with the intake flow control valve 8. The intake flow control valve 8 is arranged near the intake port 4 in the middle of the branch portion 12 defined by the intake manifold 9.

The intake flow control valve 8 is rotationally driven by an actuator from a fully opened 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 collar 20 through which the fuel spray injected from the injector 3 passes is provided. The collar 20 is formed in a cylindrical shape.

The cylinder head 10 is formed with holes 21 and 22 through which the injector 3 faces through the collar 20. The collar 20 has its proximal end inserted into the hole 21 and its distal end inserted into the hole 22.

The hole 22 is located on the downstream side of the intake flow control valve 8 and opens above the intake passage wall 26.

The cylinder head 10 is formed with a recess 15 which is continuous with the hole 22 and is recessed into a cylindrical surface. The collar 20 and the recessed portion 15 define a space through which the fuel spray injected from the injector 3 passes.

As shown in FIG. 2, the cylinder head 10
A partition wall 37 is formed to define the air supply chamber 36. The air supply chamber 36 defines a space around the collar 20 that communicates with the branch portion 12 on the upstream side of the intake flow control valve 8.

The air supply chamber 36 opens at the joint surface of the cylinder head 10 with respect to the intake manifold 9. The intake manifold 9 is formed with a sub port 35 communicating with the air supply chamber 36. The sub-port 35 extends parallel to the branch portion 12 and communicates with the intake flow control valve 8 upstream from the intake passage wall 13 of the branch portion 12 via an inlet 34 that is recessed in a concave shape.

As shown in FIG. 3, the hole 22 and the collar 20 are also shown.
An air curtain injection port (spraying passage) 18 is defined between them. The air curtain injection port 18 connects the air supply chamber 36 and the intake port 4 downstream of the intake flow control valve 8. That is, the inlet 34, the auxiliary port 35, the air supply chamber 36, and the air curtain injection port 18 constitute a bypass passage that bypasses the intake flow control valve 8 and guides intake air.

In this embodiment, the hole 22 is formed concentrically with the collar 20, and the air curtain injection port 18 is defined in an annular shape having a uniform opening width in the circumferential direction.

In the injector 3, the tip guide portion 23 having the fuel injection port opened is formed in a cylindrical shape. Tip guide part 23
The inner peripheral surface of the collar 20 on the base end side is fitted to the. This allows
The collar 20 is positioned with respect to the injector 3.

A flange 25 is formed at the base end of the cylindrical collar 20. When the injector 3 is fastened to the cylinder head 10 via a bolt (not shown), the flange 25 is attached to the injector 3 and the cylinder head 1.
It is sandwiched between the mounting seats 24 formed in 0.

A water jacket 5 is formed on the cylinder head 10. The water jacket 5 is formed near the injector 3 and the air supply chamber 36. The cooling water circulating in the water jacket 5 is kept at about 80 ° C. after warming up, and the heat of the combustion chamber wall is carried away, while the intake passage wall 26 is heated to promote the vaporization of the fuel wall flow.

The structure is as described above. Next, the operation will be described.

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 via the collar 20 and the air are mixed. Inhaled into the combustion chamber 1,
The air-fuel mixture is made uniform.

In an operating state in which the intake flow control valve 8 is closed in a predetermined low speed and low load region, the pressure difference generated before and after the intake flow control valve 8 causes the intake air to enter the inlet 34, the auxiliary port 35, and the air supply chamber 36. 2 through the air curtain nozzle 18
Eject around 0.

The intake air flow ejected from the air curtain injection port 18 wraps the diffused fuel spray as shown by the two-dot chain line in FIG. 1 and prevents the fuel spray from adhering to the intake passage wall 26 and forming a wall flow. .

Further, even if the wall flow of the fuel once occurs in the intake passage wall 26 of the intake port 5, the fuel is separated from the intake passage wall 26 by the high-speed intake flow ejected from the air curtain injection port 18.

The intake air flowing through the air supply chamber 36 and the air curtain nozzle 18 is heated by the heat transfer from the cooling water circulating through the water jacket 5 provided in the vicinity thereof, and the fuel adhering to the intake passage wall 26 is removed. When blown off, the vaporization of the fuel wall flow is promoted.

Furthermore, the intake passage wall 26 is heated by the heat transfer from the cooling water circulating in the water jacket 5, and the vaporization of the fuel wall flow is promoted.

In this way, in order to prevent the wall flow of the fuel from adhering to the intake passage wall 26, the control response of 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. . 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.

Further, the high-speed intake air flow ejected from the air curtain injection port 18 promotes atomization of the fuel, so that the ignitability of the air-fuel mixture in the combustion chamber 1 and the stability of flame propagation are improved. Since the combustion efficiency can be increased in this way, it becomes possible to retard the ignition timing and to dilute the air-fuel ratio when cold, raise the exhaust temperature and shorten the temperature rising time of the catalyst, and discharge the unburned HC. Can be significantly reduced.

The manufacturing process of the intake manifold 9 is as follows.
At the time of casting, the branch portion 12 and the inlet 34 are formed by using one core, and the sub port 35 is formed by using a mold.

Therefore, the intake manifold 9 can be formed in the same manufacturing process as the conventional intake manifold having neither the inlet 34 nor the sub port 35, and the productivity is not impaired.

In the manufacturing process of the cylinder head 10, the air supply chamber 36 is formed by using a mold at the time of casting. After the cylinder head 10 is cast, the mounting seat 24, the holes 21, 22 and the like are formed by machining. Mounting seat 24, holes 21, 22
Are arranged concentrically, the holes 21 and 22 can be machined coaxially with the mounting seat 24.

Therefore, the cylinder head 10 can be formed by the same manufacturing process as the conventional cylinder head having no air supply chamber, and the productivity is not impaired.

Since the intake air bypassing the intake air flow control valve 8 is guided to the air curtain injection port 18 via the inlet 34, the auxiliary port 35, and the air supply chamber 36, an elongated hole formed by external piping or machining There is no need for the like, and the structure can be simplified.

The flange 20 of the cylindrical collar 20 defining the air curtain nozzle 18 has the injector 3
And a mounting seat 24 formed on the cylinder head 10, the structure is such that the collar 20 is connected to the cylinder head 10 without using a bolt or the like for connecting the collar 20 to the cylinder head 10. Compared with this, it is possible to suppress deterioration of productivity.

The air curtain nozzle 18 is connected to the cylinder head 1
Since the structure is defined by the collar 20 inserted into 0, the cross-sectional area of the air curtain nozzle 18 is adjusted by changing the outer diameter of the collar 20, and it becomes easy to respond to changes in engine specifications, etc. You can enhance your sex.

Next, another embodiment shown in FIG. 5 will be described. The parts corresponding to those in FIG. 1 are designated by the same reference numerals.

The cylinder head 10 is formed with holes 21 and 31 through which the injector 3 faces through the collar 20. The base end of the collar 20 is inserted into the hole 21 without a gap, and the tip end thereof is inserted into the hole 31 without a gap. The inner diameters of the holes 21 and 31 are set to be substantially equal to the outer diameter of the collar 20.

As also shown in FIG. 6, the air supply chamber 36 defines a space around the collar 20 which communicates with the branch portion 12 upstream of the intake flow control valve 8.

As shown in FIG. 7, the cylinder head 10
A hole 32 defining an air curtain nozzle 38 is formed between the collars 20.

The hole 32 is formed eccentrically with respect to the hole 31 and the collar 20. The holes 32 define an air curtain jet 38 with a crescent-shaped cross section, limited to the upper portion of the collar 20.

With the above arrangement, the operation will be described.

In a predetermined low speed and low load region, 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 the intake air to pass through the air supply chamber 36 and the air curtain injection port 38. Is jetted along the upper portion of the intake passage wall 26.

In the operating state in which the intake flow control valve 8 is closed, the fuel spray injected from the injector 3 to the upper part of the intake port 4 diffuses as shown by the chain double-dashed line in FIG. It tends to adhere to the upper portion of the passage wall 26.

The intake flow ejected from the air curtain injection port 38 forms an air layer on the fuel spray and the intake passage wall 26, and prevents the fuel spray from adhering to the intake passage wall 26 and forming a wall flow.

In addition, the air curtain nozzle 38 is provided with a collar 20.
Since it is limited to the upper part of the
Even if a wall flow of the fuel is once generated in the intake passage wall of the intake port 5 by increasing the flow velocity of the air ejected from the intake port 5, the fuel can be separated from the intake passage wall 26 by the high-speed intake flow ejected from the air curtain injection port 38. .

The intake air flowing through the air supply chamber 36 and the air curtain nozzle 18 is heated by the heat transfer from the cooling water circulating in the water jacket 5 provided in the vicinity thereof, and the fuel adhering to the intake passage wall 26 is removed. When blown off, the vaporization of the fuel wall flow is promoted.

The flange 20 of the collar 20 is sandwiched between the injector 3 and the mounting seat 24 formed on the cylinder head 10 to be joined, and holes 21, 32 are formed in the middle thereof.
The support rigidity of the collar 20 with respect to the cylinder head 10 can be increased by the structure in which the collar 20 is fitted with no gap.

Next, another embodiment shown in FIG. 8 will be described. The parts corresponding to those in FIG. 1 are designated by the same reference numerals.

The cylinder head 10 is formed with holes 42 and 43 through which the injector 3 faces via the collar 40. The collar 40 has its base end inserted into the hole 42 without any gap, and its tip part inserted into the hole 43 without any gap.

As shown in FIG. 9, the cylindrical collar 40 has two assist air jets (spraying passages) 41.
Are formed facing the air supply chamber 36. That is, each assist air injection port 41 communicates the air supply chamber 36 with the inside of the collar 40. Each assist air jet 41 is arranged on both sides of the collar 40.

In the injector 3, the tip guide portion 23 having the fuel injection port opened is formed in a cylindrical shape. Tip guide part 23
The inner peripheral surface of the collar 40 on the base end side is fitted to the. This allows
The collar 40 is positioned with respect to the injector 3.

As shown in FIG. 10, a flange 45 is formed at the base end of the cylindrical collar 40. The injector 3 has a cylinder head 10 through a bolt (not shown).
The flange 45 is sandwiched between the injector 3 and the mounting seat 24 formed on the cylinder head 10 by being fastened.

With the above construction, 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 from the branch portion 12 through the inlet 34, the auxiliary port 35, and the air supply chamber 36 to the collar 40 from the assist air injection port 41.
Squirt inside.

The high-velocity intake air flow ejected from the assist air injection port 41 promotes atomization of the fuel, so that the ignitability of the air-fuel mixture in the combustion chamber 1 and the stability of flame propagation are improved.
Since the combustion efficiency can be increased in this way, it becomes possible to retard the ignition timing and to dilute the air-fuel ratio when cold.
It is possible to raise the exhaust gas temperature to shorten the temperature rising time of the catalyst, and to significantly reduce the amount of unburned HC discharged.

The intake air flowing into the assist air injection port 41 from the air supply chamber 36 is heated by the heat transfer from the cooling water circulating through the water jacket 5 provided in the vicinity thereof, and is ejected to the intake port 36 via the collar 40. The fuel vaporization is accelerated.

Further, the intake passage wall 26 is heated by the heat transfer from the cooling water circulating in the water jacket 5, and the vaporization of the fuel wall flow is promoted.

Next, another embodiment shown in FIG. 11 will be described. The parts corresponding to those in FIG. 10 and the like are designated by the same reference numerals.

The flange 45 is formed offset from the collar 40 by a predetermined value L. As a result, the width of the flange 45 changes in the circumferential direction.

The mounting seat 24 for the flange 45 of the cylinder head is also offset from the collar 40 by a predetermined value L.

In this case, the collar 40 has its flange 45
Mounting seat 2 formed on the injector and cylinder head
4 are sandwiched and joined together, the positioning of the collar 40 in the rotational direction with respect to the cylinder head is carried out by the structure in which the hole into which the mounting seat 24 and the collar 40 are fitted is eccentric.

Next, another embodiment shown in FIG. 12 will be described.

On the cylindrical collar 50, a guide cylinder portion 52 that defines two assist air injection holes 51 is formed into a cylindrical shape by press working. Each of the assist air injection holes 51 is arranged coaxially and opens inside the collar 50 so as to face each other.

In this case, in the operating state in which the intake flow control valve 8 is closed, the assist air injection port 51 passes through the air supply chamber 36.
The intake flow ejected from the inside of the collar 50 to the inside of the collar 50 is guided by the guide cylinder portion 52 and flows in from the direction orthogonal to the collar 50, so that atomization of the fuel is promoted.

The intake air jetted to the collar 50 through the assist air jet ports 51 facing each other collide with each other at the collar 50, and the velocity components for deflecting the fuel spray injected from the injector are canceled each other. For this reason,
The fuel spray passing through the collar 50 while being collided with the high-speed intake air flow ejected from each assist air injection port 51 is suppressed from being deflected toward the wall surface of the intake passage, and may adhere to the wall surface of the intake passage to form a wall flow. To be prevented.

Next, another embodiment shown in FIG. 13 will be described.

The resin collar 60 is formed in a cylindrical shape.
Two assist air injection holes 61 are formed in the collar 60 in a port shape. That is, the assist air ejection port 61 defines a space having a right cylindrical shape.

The assist air nozzles 61 are coaxially arranged and open inside the collar 60 so as to face each other.

The collar 60 is formed with a recess 64 that fits into the tip of the injector, and also has a conical fuel spray passage 63 through which the fuel injected from the injector passes.

In this case also, in the operating state in which the intake flow control valve 8 is closed, the assist air injection port 6 passes through the air supply chamber 36.
The intake flow ejected from No. 1 into the collar 60 is guided by the guide tube portion 62 and flows in from the direction orthogonal to the collar 60, so that atomization of the fuel can be promoted.

Further, the intake flow jetted into the collar 60 through the two assist air nozzles 61 is
The fuel spray collides with each other so as to sandwich the fuel spray, and promotes atomization of the fuel.

Next, another embodiment shown in FIG. 14 will be described.

A flange 75 is formed on the base end portion of the collar 70, and an annular protrusion 76 is formed on the tip end portion.

Before the injector is assembled to the cylinder head, the annular projection 76 is fitted into the hole with a shrink fit while the collar 70 is inserted into the cylinder head to prevent the collar 70 from coming off. Therefore, it is possible to unitize the collar 70 inserted in the cylinder head and improve the productivity.

The injector 45 is fastened to the cylinder head via a bolt (not shown), so that the flange 45
Are sandwiched between the injector 3 and the mounting seat formed on the cylinder head.

Thus, in the state where the collar 70 is assembled to the cylinder head, the annular protrusion 76 fits in the hole of the cylinder head without a gap, and the sealing property between the collar 70 and the hole can be improved.

Next, another embodiment shown in FIG. 15 will be described. The parts corresponding to those in FIG. 8 and the like are designated by the same reference numerals.

A sealing material 46 is attached to the flange 45 of the collar 40.
Is attached. The seal member 46 is formed in an annular shape having a U-shaped cross section, and is joined so as to wrap both sides of the flange 45.

The flange 45 is joined to the mounting seat 24 and the injector 3 via the sealing material 46 to ensure the hermeticity of the collar 40 and the mounting portion of the injector 3.

With the structure in which the sealing material 46 is integrated with the collar 40 as described above, the assembling property can be improved, and the sealing material 46 can be securely assembled.

Next, another embodiment shown in FIG. 16 will be described.

The flange 66 of the collar 65 is provided with a sealing material 67.
To the mounting seat of the cylinder head via the collar 65
And it is designed to ensure the hermeticity of the injector mounting part.

The sealing material 67 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 66.

With the structure in which the sealing material 67 is integrated with the collar 65 in this manner, the assembling property can be improved and the sealing material 67 can be securely assembled.

Next, another embodiment shown in FIG. 17 will be described. The parts corresponding to those in FIG. 1 are designated by the same reference numerals.

The collar 80 has a protector portion 81 projecting annularly from the inner peripheral surface thereof, and these are integrally formed by using resin as a material. The base end of the collar 80 is the injector 3
The tip end guide portion 23 is fitted, and the protector portion 81 abuts on the tip end surface of the tip end guide portion 23. A fuel injection port is opened inside the protector section 81 on the tip end surface of the tip guide section 23.

A seal material 83 is interposed between the injector 3 and the mounting seat 84 of the cylinder head 10 to seal this portion.

In this case, the collar 80 is attached to the protector section 81.
With the structure in which the collar 80 and the ejector 3 are assembled into the ejector 3, the productivity can be improved by uniting the collar 80 and the ejector 3. Next, another embodiment shown in FIG. 18 will be described. The parts corresponding to those in FIG. 1 are designated by the same reference numerals.

An opening / closing valve 91 is provided at the opening of the air supply chamber 36 to the branch portion 12.

A cylindrical valve seat 92 is attached to the opening of the air supply chamber 36 for the branch portion 12. A thin plate-shaped valve element 93 is seated on the back side of the valve seat 92.

As shown in FIG. 19, a C-shaped notch 94 is formed in the disc-shaped valve body 93. Notch 94
An outer peripheral portion 95 located on the outer side of is fixed to the opening of the inlet 34 via the valve seat 92.

With the above arrangement, 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
The on-off valve 91 opens with its valve element 93 separated from the valve seat 92, and intake air is ejected from the air curtain injection port 18 through the branch portion 12, the inlet 34, the sub port 35, and the air supply chamber 36.

In the operating state in which the intake flow control valve 8 is opened, the on-off valve 91 has its valve body 93 seated on the valve seat 92 and closed, and the burnt gas blown back to the branch portion 12 via the intake port is branched. Inflow from the portion 12 to the inlet 34, the auxiliary port 35, the air supply chamber 36, etc. is suppressed, and it is possible to prevent deposits from accumulating on these.

Next, another embodiment shown in FIG. 20 will be described.

An opening / closing valve 95 is provided at the opening of the air supply chamber for the branch portion.

A cylindrical valve seat 97 is attached to the opening of the air supply chamber for the branch portion. A cylindrical valve body 98 is housed inside the valve seat 97.

On the valve seat 97, a seat portion 99 for seating the valve body 98 is formed in an annular shape. A protrusion 96 is formed on the valve body 98. The protrusion 96 is the valve seat 9
By contacting the top plate 89 of No. 7, the lift amount of the valve body 98 is regulated. A plurality of holes 88 are opened in the top plate 89.

In the operating state in which the intake flow control valve is closed,
Due to the pressure difference generated before and after the intake flow control valve, the valve element 98 of the on-off valve 95 has a seat portion 99 of the valve seat 97.
And the intake air flows between the valve seat 97 and the valve body 98 as shown by the arrow in the figure.

In the operating state in which the intake flow control valve opens,
The on-off valve 95 has its valve body 98 seated on the seat portion 99 of the valve seat 97 to be closed, so that the burnt gas that is blown back to the branch portion via the intake port is prevented from flowing into the inlet, and the deposits are accumulated on these. Accumulation can be prevented.

Next, the embodiment shown in FIG. 21 will be described. The parts corresponding to those in FIG.

The intake flow control valve 8 is attached to the cylinder head 10.
Is interposed. The intake flow control valve 8 is the cylinder head 1.
It is arranged in the middle of the intake port 4 defined as zero.

The intake flow control valve 8 is rotationally driven by the actuator from a fully opened position substantially parallel to the passage centerline of the intake passage 2 to a fully closed position substantially orthogonal to the passage centerline of the intake passage 2.

A collar 20 through which the fuel spray injected from the injector 3 passes is provided. The collar 20 is formed in a cylindrical shape.

The cylinder head 10 is formed with holes 21 and 22 through which the injector 3 faces via the collar 20. The collar 20 has its proximal end inserted into the hole 21 and its distal end inserted into the hole 22.

As shown in FIG. 22, the cylinder head 1
A partition wall 17 that defines the air supply chamber 16 that is recessed in a concave shape with respect to the intake passage wall 26 of 0 is formed. The air supply chamber 16 defines a space around the collar 20 that opens to the intake port 4 on the upstream side of the intake flow control valve 8.

The partition wall 17 defining 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. Hole 22 for inserting the collar 20 into the partition wall 17
Are formed.

The air supply chamber 16 has a cross-sectional area of the intake port 4
It is formed so as to be recessed in a taper shape that widens toward.

As shown in FIG. 23, the hole 22 and the collar 2 are provided.
During 0, the air curtain nozzle (spray processing passage) 18 is defined. The air curtain injection port 18 connects the air supply chamber 16 and the intake port 4 downstream of the intake flow control valve 8. That is, the air supply chamber 16 and the air curtain nozzle 18 form a bypass passage that bypasses the intake flow control valve 8 and guides intake air.

In this embodiment, the hole 22 is formed concentrically with the collar 20, and the air curtain nozzle 18 is defined in an annular shape having a uniform opening width in the circumferential direction.

In the injector 3, the tip guide portion 23 having the fuel injection port opened is formed in a cylindrical shape. Tip guide part 23
The inner peripheral surface of the collar 20 on the base end side is fitted to the. This allows
The collar 20 is positioned with respect to the injector 3.

A flange 25 is formed at the base end of the cylindrical collar 20. When the injector 3 is fastened to the cylinder head 10 via a bolt (not shown), the flange 25 is attached to the injector 3 and the cylinder head 1.
It is sandwiched between the mounting seats 24 formed in 0.

A water jacket 5 is formed on the cylinder head 10. Water jacket 5 is air supply chamber 16
It is formed close to the intake passage wall 26.

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 via the collar 20 is mixed with air. Inhaled into the combustion chamber 1,
The air-fuel mixture is made uniform.

In an operating state in which the intake flow control valve 8 is closed in a predetermined low speed and low load region, the pressure difference generated before and after the intake flow control valve 8 causes the intake air to pass through the air supply chamber 16 and the air curtain injection port 18 Squirts around the collar 20.

The intake air flow ejected from the air curtain injection port 18 wraps the diffused fuel spray as shown by the chain double-dashed line in FIG. 21, and prevents the fuel spray from adhering to the intake passage wall 26 and forming a wall flow. .

Further, even if the wall flow of fuel once occurs in the intake passage wall 26 of the intake port 5, the fuel is separated from the intake passage wall 26 by the high-speed intake flow ejected from the air curtain injection port 18.

The intake air flowing through the air supply chamber 16 and the air curtain nozzle 18 is heated by the heat transfer from the cooling water circulating in the water jacket 5 provided in the vicinity thereof, and the fuel adhering to the intake passage wall 26 is removed. When blown off, the vaporization of the fuel wall flow is promoted.

Furthermore, the heat transfer from the cooling water circulating through the water jacket 5 heats the intake passage wall 26 to promote the vaporization of the fuel wall flow.

In this way, in order to prevent the wall flow of the fuel from adhering to the intake passage wall 26, 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 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.

In the manufacturing process of the cylinder head 10, the air supply chamber 36 and the intake port 4 are molded using a common core during casting. After casting the cylinder head 10, the mounting seat 2
4, holes 21, 22 and the like are formed by machining.

Since the air supply chamber 16 is recessed in a taper shape that expands toward the intake port 4, when forming the core, the part forming the intake port 4 and the part forming the air supply chamber 16 are separated. There is no need to mold with a mold. That is, it is possible to form a core in which the portion for forming the intake port 4 and the portion for forming the air supply chamber 16 are integrated by using a mold that is divided into upper and lower parts.

Mounting seat 2 formed on cylinder head 10
4 and holes 21 and 22 are arranged concentrically, so hole 2
The machining of 1 and 22 can be performed coaxially with the mounting seat 24.

Therefore, the cylinder head 10 can be formed by the same manufacturing process as the conventional cylinder head having no air supply chamber, and the productivity is not impaired.

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 20 that allows the fuel from the injector 3 to pass through is separated by the partition wall 1.
Due to the structure that is provided so as to penetrate through 7, it is possible to define an air curtain injection port 18 that communicates between the front and rear of the intake flow control valve 8 between the partition wall 17 and the collar 20.

Since the intake air bypassing the intake air flow control valve 8 is guided to the air curtain injection port 18 via the air supply chamber 16, an external pipe or an elongated hole formed by machining may be required. No, the structure is simplified.

Next, another embodiment shown in FIG. 24 will be described. The parts corresponding to those in FIG. 21 are designated by the same reference numerals.

The cylinder head 10 is formed with holes 21 and 31 which the injector 3 faces through the collar 20. The base end of the collar 20 is inserted into the hole 21 without a gap, and the tip end thereof is inserted into the hole 32 without a gap. The inner diameters of the holes 21 and 31 are set to be substantially equal to the outer diameter of the collar 20.

As shown in FIG. 25, the cylinder head 1
An air supply chamber 16 that is recessed in a concave shape with respect to the intake passage wall 26 of 0 is formed. The air supply chamber 16 defines a space around the collar 20 that opens to the intake port 4 upstream of the intake flow control valve 8.

As shown in FIG. 26, the cylinder head 1
Holes 32 that define air curtain nozzles 38 are formed between the collars 20 at 0.

The hole 32 is formed eccentrically with respect to the hole 31 and the collar 20. The holes 32 define an air curtain jet 38 with a crescent-shaped cross section, limited to the upper portion of the collar 20.

With the above arrangement, the operation will be described.

In a predetermined low speed and low load region, 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 the intake air to pass through the air supply chamber 16 and the air curtain injection port 38. Is jetted along the upper portion of the intake passage wall 26.

In the operating state in which the intake flow control valve 8 is closed, the fuel spray injected from the injector 3 to the upper part of the intake port 4 diffuses as shown by the chain double-dashed line in FIG. It tends to adhere to the upper portion of the passage wall 26.

The intake air flow ejected from the air curtain injection port 38 forms an air layer in the fuel spray and the intake passage wall 26, and prevents the fuel spray from adhering to the intake passage wall 26 and forming a wall flow.

The air curtain nozzle 38 has a collar 20.
Since it is limited to the upper part of the
Even if a wall flow of the fuel is once generated in the intake passage wall of the intake port 5 by increasing the flow velocity of the air ejected from the intake port 5, the fuel can be separated from the intake passage wall 26 by the high-speed intake flow ejected from the air curtain injection port 38. .

The flange 20 of the collar 20 is sandwiched between the injector 3 and the mounting seat 24 formed on the cylinder head 10 to be joined, and the holes 21, 31 are formed in the middle thereof.
The support rigidity of the collar 20 with respect to the cylinder head 10 can be increased by the structure in which the collar 20 is fitted with no gap.

Next, another embodiment shown in FIG. 27 will be described. The parts corresponding to those in FIG. 21 are designated by the same reference numerals.

The cylinder head 10 is formed with holes 42 and 43 through which the injector 3 faces via the collar 40. The collar 40 has its base end inserted into the hole 42 without any gap, and its tip part inserted into the hole 43 without any gap.

As shown in FIG. 28, the cylindrical collar 40 has two assist air injection ports (spraying passages) 4.
1 is formed facing the air supply chamber 36. That is, each assist air injection port 41 communicates the air supply chamber 36 with the inside of the collar 40. Each assist air jet 41 is arranged on both sides of the collar 40.

The flange 45 is joined to the mounting seat 24 and the injector 3 via a sealing material 46 so as to ensure the hermeticity of the collar 40 and the mounting portion of the injector 3. The seal member 46 is formed in an annular shape having a U-shaped cross section, and is joined so as to wrap both sides of the flange 45.

With the structure in which the sealing material 46 is integrated with the collar 40 as described above, the assembling property can be improved and the assembling of the sealing material 46 can be surely performed.

With the above arrangement, 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 16 and is ejected from the assist air ejection port 41 into the inside of the collar 40.

The high-speed intake air flow jetted from the assist air jet port 41 promotes atomization of the fuel, so that the ignitability of the air-fuel mixture and the stability of flame propagation in the combustion chamber 1 are improved.
Since the combustion efficiency can be increased in this way, it becomes possible to retard the air-fuel ratio during cold conditions, raise the exhaust temperature and shorten the temperature rise time of the catalyst, and significantly reduce the amount of unburned HC emitted. It can be reduced.

The intake air flowing into the assist air injection port 41 from the air supply chamber 36 is heated by the heat transfer from the cooling water circulating in the water jacket 5 provided in the vicinity thereof, and is ejected to the intake port 36 via the collar 40. The fuel vaporization is accelerated.

Further, the intake passage wall 26 is heated by the heat transfer from the cooling water circulating in the water jacket 5, and the vaporization of the fuel wall flow is promoted.

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 40 that allows the fuel from the injector 3 to pass through is separated by the partition wall 1.
7 is provided so that the collar 40 can communicate with the front and rear of the intake flow control valve 8 through the assist air injection port 41.
Can be opened.

Since the intake air bypassing the intake air flow control valve 8 is guided to the assist air injection port 41 through the air supply chamber 16, an external pipe or an elongated hole formed by machining may be required. No, the structure is simplified.

Next, another embodiment shown in FIG. 29 will be described. The same parts as those in FIG. 21 are designated by the same reference numerals.

An opening / closing valve 91 is provided at the opening of the air supply chamber 16 for the intake port 4. Intake port 4 of air supply chamber 16
An annular valve seat 92 is attached to the opening for. A thin plate-shaped valve element 93 is seated on the back side of the valve seat 92.

In this case, in the operating state in which the intake flow control valve 8 is closed, the valve body 93 of the opening / closing valve 91 is closed by the valve seat 92 due to the pressure difference generated before and after the intake flow control valve 8.
The valve is opened away from the intake port, and intake air flows from the intake port 4
And is jetted from the air curtain jet port 18.

In the operating state in which the intake flow control valve 8 is opened, the valve body 93 of the on-off valve 91 is seated on the valve seat 92 and closed, and the burned gas which is blown back to the intake port 4 enters the air supply chamber 16. Inflow is suppressed, and deposits can be prevented from accumulating in the air supply chamber 16.

..

As described above, in the intake system for an internal combustion engine according to claim 1, the intake air flowing through the air supply chamber to the spray processing passage in the operating state in which the intake flow control valve is closed is close to this. It is possible to improve the combustibility by promoting the vaporization of the fuel that is heated by the heat transfer from the cooling water circulating in the water jacket that is provided and is injected into the intake port through the collar. Further, due to the structure in which the collar through which the fuel from the injector is passed penetrates through the air supply chamber and the partition wall, it becomes possible to define the spray processing passage for guiding the intake air bypassing the intake flow control valve through the collar. As a result, there is no need for external piping or elongated holes formed in machining, the structure is simplified, and the cost of the product is reduced.

An intake system for an internal combustion engine according to claim 2 is
Since the auxiliary port that guides intake air to the air supply chamber is formed by casting in the intake manifold, there is no need for external piping or elongated holes formed by machining, and the structure is simplified. Product cost can be reduced.

An intake system for an internal combustion engine according to claim 3 is
The partition wall that defines the air supply chamber faces the outer peripheral portion of the intake flow control valve in the closed position, and the collar that allows the fuel from the injector to pass through is provided by the structure that allows the intake air to pass through the collar. It is possible to define a spray processing passage that guides intake air that bypasses the flow control valve, and does not require an external pipe or an elongated hole formed by machining, thereby simplifying the structure.

The intake system for an internal combustion engine according to claim 4 is
Since the air supply chamber is recessed in a taper shape with respect to the intake passage wall of the intake port, when molding the cylinder head, the mold for forming the branch of the core and the mold for forming the air supply chamber are separated from each other by a mold. With this, there is no need to mold and productivity can be improved.

The intake system for an internal combustion engine according to claim 5 is
Due to the structure that defines the air curtain injection port that connects the front and back of the intake flow control valve between the partition wall and the collar, the intake flow ejected from the air curtain injection port when the intake flow control valve is closed It wraps the fuel spray that jets out and diffuses in the passage to prevent the fuel spray from adhering to the wall of the intake passage and forming a wall flow, improving the air-fuel ratio control response during transients, improving emission, and improving fuel economy. Can be reduced.

The intake system for an internal combustion engine according to claim 6 is
Due to the structure in which the air curtain nozzle opening is limited to the upper part of the collar arranged in the upper part of the intake passage, an air layer is formed between the fuel spray and the intake passage wall, and the fuel spray adheres to the intake passage wall. Wall flow is prevented, air-fuel ratio control responsiveness is improved during transients, emissions are improved, and fuel consumption is reduced.

An intake system for an internal combustion engine according to claim 7 is
Due to the structure in which the assist air jet that connects the front and rear of the intake flow control valve to the partition wall is opened, the high-speed intake air jetting from the assist air jet collides with the fuel passing through the collar when the intake flow control valve is closed. And promotes atomization of the fuel, and the combustion efficiency can be increased from the cold state, and unburned H
The discharge amount of C can be significantly reduced.

An intake system for an internal combustion engine according to claim 8 is
In the operating state in which the intake flow control valve is closed, the intake flow ejected from the air supply chamber through the assist air injection port into the collar is guided by the guide tube portion and flows in in a predetermined direction with respect to the collar. Atomization can be promoted and combustibility can be enhanced.

An intake system for an internal combustion engine according to claim 9 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 assist air ejection port is guided by the port-shaped assist air ejection port and flows in from a predetermined direction with respect to the collar. Therefore, atomization of fuel can be promoted and combustibility can be improved.

In the intake system for an internal combustion engine according to a tenth aspect of the present invention, in the operating state in which the intake flow control valve is closed, the intake air ejected to the collar through the assist air nozzles facing each other collide with each other in the collar. However, since the velocity components that deflect the fuel spray injected from the injectors cancel each other out, the fuel spray that passes through the collar while colliding with the high-speed intake air flow ejecting from each assist air injection port is deflected toward the wall surface of the intake passage. This can be suppressed, and it can be prevented that the wall flow adheres to the wall surface of the intake passage.

In the intake system for an internal combustion engine according to the eleventh aspect, the collar is positioned with respect to the injector and the collar is fastened by the structure in which the inner peripheral surface of the collar at the base end side is fitted to the tip guide portion of the injector. The structure can be simplified without the need for bolts or the like.

In the intake system for an internal combustion engine according to a twelfth aspect of the present invention, the structure is such that the tip end guide portion of the injector with which the base end inner peripheral surface of the collar fits and the mounting seat with which the flange engages are eccentric. It is possible to eliminate the pins and the like that prevent the collar from rotating with respect to the cylinder head, and simplify the structure.

In the intake system for an internal combustion engine according to claim 13, before assembling the injector to the cylinder head,
By fitting the annular projection formed on the tip of the collar into the hole of the cylinder head, the collar is prevented from coming off and these parts can be unitized,
Increases productivity.

The intake system for an internal combustion engine according to claim 14 has a structure in which a seal member for joining at least one of the injector and the cylinder head is joined to the flange portion.
It is possible to improve the assemblability of the collar to the cylinder head and surely assemble the seal material.

In the intake system for the internal combustion engine according to the fifteenth aspect, the collar and the ejector are unitized by the structure in which the collar is assembled to the ejector through the protector portion, and the productivity can be enhanced.

In the intake system for an internal combustion engine according to a sixteenth aspect, in the operating state in which the intake flow control valve is opened, the open / close valve is closed, and the burnt gas blown back to the branch portion through the intake port is inside the collar. It is possible to suppress the inflow of the air into the air supply chamber and to prevent deposits from accumulating in the air supply chamber.

[Brief description of the drawings]

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

FIG. 2 is a sectional view taken along the line AA in FIG. 1;

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a sectional view taken along line C-C of FIG.

FIG. 5 is a sectional view of an intake manifold and the like showing another embodiment.

FIG. 6 is a sectional view taken along line AA of FIG.

7 is a sectional view taken along line BB of FIG.

FIG. 8 is a cross-sectional view of an engine showing still another embodiment.

9 is a sectional view taken along line AA of FIG.

FIG. 10 is a front view and a sectional view of a collar showing still another embodiment.

FIG. 11 is a front view of a collar showing still another embodiment.

FIG. 12 is a sectional view of a collar showing still another embodiment.

FIG. 13 is a sectional view of a collar showing still another embodiment.

FIG. 14 is a side view of a collar showing still another embodiment.

FIG. 15 is a cross-sectional view of an engine showing still another embodiment.

FIG. 16 is a sectional view of a collar showing still another embodiment.

FIG. 17 is a cross-sectional view of an engine showing still another embodiment.

FIG. 18 is a cross-sectional view of an engine showing still another embodiment.

FIG. 19 is a plan view of the valve body of the same.

FIG. 20 is a cross-sectional view of an on-off valve showing still another embodiment.

FIG. 21 is a cross-sectional view of an engine showing still another embodiment.

FIG. 22 is a sectional view taken along the line AA of FIG.

FIG. 23 is a sectional view taken along line BB of FIG. 21.

FIG. 24 is a cross-sectional view of an engine showing still another embodiment.

FIG. 25 is a sectional view taken along line AA of FIG.

FIG. 26 is a sectional view taken along line BB of FIG.

FIG. 27 is a cross-sectional view of an engine showing still another embodiment.

28 is a sectional view taken along line AA of FIG. 27.

FIG. 29 is a cross-sectional view of an engine showing still another embodiment.

FIG. 30 is a cross-sectional view of an engine showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustion chamber 3 Injector 4 Intake port 5 Water jacket 8 Intake flow control valve 9 Intake manifold 10 Cylinder head 11 Intake passage 12 Branch part 16 Air supply chamber 17 Partition wall 18 Air curtain nozzle 20 Color 23 Tip guide part 22 Hole 24 Mounting seat 25 Flange 35 Sub-port 36 Air Supply Chamber 37 Partition Wall 41 Assist Air Jet 40 Color 45 Hole 46 Sealant

Claims (16)

[Claims] 1. A butterfly type intake flow control valve for forming an intake port for introducing intake air into a combustion chamber in a cylinder head, the intake passage being throttled in accordance with operating conditions. The intake flow control valve is provided upstream of the intake flow control valve. The communicating air supply chamber is formed in the cylinder head, the partition wall that defines the air supply chamber is formed in the cylinder head, and the water jacket that circulates the cooling water in the vicinity of the air supply chamber is formed in the cylinder head. An injector for injection is attached to the cylinder head, and it has a collar that guides the fuel injected from the injector through the air supply chamber and the partition wall to the intake passage downstream from the intake flow control valve. An intake system for an internal combustion engine, characterized in that a spray processing passage communicating with an intake port downstream of an intake flow control valve is defined. 2. A butterfly type intake flow control valve for forming a branch portion for guiding intake air to the intake port in an intake manifold, wherein the branch portion is throttled according to operating conditions. The intake device for an internal combustion engine according to claim 1, wherein a sub-port that connects the upstream branch portion and the air supply chamber is formed in the intake manifold by casting. 3. A supply air which is provided with a butterfly type intake flow control valve for narrowing said intake port in accordance with operating conditions in a cylinder head, and which is concavely recessed with respect to an intake passage wall upstream from the intake flow control valve. 2. The internal combustion engine according to claim 1, wherein the chamber is defined by a cylinder head, and a partition wall that defines the air supply chamber is formed so as to face the outer peripheral portion of the intake flow control valve in the closed position. Intake device. 4. The intake system for an internal combustion engine according to claim 3, wherein the air supply chamber is recessed so that its cross-sectional area expands toward the branch portion. 5. The internal combustion engine according to claim 1, wherein an air curtain nozzle is defined between the collar and a hole through which a collar penetrates the partition wall as the spray processing passage. Intake device. 6. The intake system for an internal combustion engine according to claim 5, wherein the collar faces the upper part of the intake passage, and the air curtain injection port is opened only in the upper part of the collar. 7. The intake system for an internal combustion engine according to claim 1, wherein an assist air jet opening that faces the air supply chamber is formed in the collar as the spray processing passage. . 8. The intake system for an internal combustion engine according to claim 7, wherein the collar is formed in a tubular shape, and a guide tubular portion that defines the assist air injection port is formed in a tubular shape in the collar. 9. 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 a port shape in the collar. The intake system for an internal combustion engine according to claim 7, wherein: 10. The intake system for an internal combustion engine according to claim 8, wherein the plurality of assist air injection ports are opened so as to face each other inside the collar. 11. The injector is formed with a distal end guide portion into which a proximal end inner peripheral surface of the collar is fitted, and a flange sandwiched between the injector and the intake manifold is formed at the proximal end portion of the collar. The intake system for an internal combustion engine according to any one of claims 1 to 10. 12. The internal combustion engine according to claim 11, wherein a mounting seat that engages with the flange is formed in the intake manifold, and the flange and the mounting seat are eccentric with respect to the tip guide portion of the injector. Inhaler. 13. The intake system for an internal combustion engine according to claim 1, wherein an annular protrusion that fits into a hole of the intake manifold is formed at the tip of the collar. . 14. A flange, which is sandwiched between an injector and an intake manifold, 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 manifold is joined to the flange portion. An intake system for an internal combustion engine according to any one of claims 1 to 13. 15. A protector portion for fitting with an ejector is formed on the collar.
An intake device for an internal combustion engine according to any one of the above. 16. The on-off valve according to claim 1, further comprising an opening / closing valve that opens an opening of the air supply chamber to the intake passage by a pressure difference generated before and after the intake flow control valve. Intake device for internal combustion engine.