JP2003278551A - Intake device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid increase of ventilation resistance in a high load region by a partition plate provided in an intake port. <P>SOLUTION: The partition plate 9 for partitioning the intake port 8 into two up and down intake passages 8a, 8b is provided, and a valve 10 for opening and closing the intake passage 8b on a lower side is provided to make intake air flow in an eccentric manner by closing the valve 10 to cause a strong tumble stream in a combustion chamber 3. The partition plate 9 is constituted so as to slide and move forward and backward in the direction of extension of the intake port 8 in conjunction with opening and closing operations of the valve 10. When a tumble stream is generated by closing the valve 10, a tip of the partition plate 9 approaches a valve stem 5a of an intake valve 5. When the valve 10 is opened, the partition plate 9 retreats from a combustion chamber 3 side and is displaced up to a position where a passage area of the intake passage 8a on an upper side is not throttled by the valve stem 5a. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system for an internal combustion engine, and more particularly to an intake system for generating a strong intake swirl flow in a combustion chamber.

[0002]

2. Description of the Related Art Conventionally, in an in-cylinder direct injection gasoline engine in which fuel is directly injected into a cylinder, an intake port is divided into two upper and lower intake passages by a partition plate, and one of the two intake passages is opened and closed. When a tumble control valve (hereinafter abbreviated as TCV) is provided to generate a strong tumble flow in the combustion chamber, the TCV
There is known an air intake device configured to close the air conditioner (see Japanese Patent Laid-Open No. 2002-038953).

[0003]

In order to generate a strong tumble flow in the combustion chamber in the intake system having the above structure, it is desired that the partition plate be extended to a position near the combustion chamber. There has been a problem that the partition plate acts as a resistance to reduce the intake amount near the fully open position of the throttle, which requires a large amount of intake air.

As a factor for reducing the intake air amount, it is considered that the actual sectional area is decreased by the partition plate and the viscous resistance is increased by increasing the area in contact with air by the partition plate. By extending the plate to the vicinity of the combustion chamber, the upper intake passage partitioned by the partition plate is throttled by the valve stem (and valve guide) of the intake valve, and the passage area of the upper intake passage decreases and changes at a large rate. It is thought that it has a large ventilation resistance.

The present invention has been made in view of the above problems, and provides an intake system for an internal combustion engine capable of reducing a ventilation resistance in a high load range while achieving a strong intake swirl flow by a partition plate. The purpose is to

[0006]

Therefore, the invention according to claim 1 is provided with a partition plate for partitioning the inside of the intake port into a plurality of intake passages, and a valve for opening and closing a part of the plurality of intake passages, In the intake device that generates a strong intake swirl flow in the combustion chamber by closing the valve, the partition plate is configured to be moved forward and backward in the intake port extending direction.

According to the above construction, the partition plate for partitioning the intake port is configured to be movable forward and backward in the direction of extension of the intake port by the moving means, and compared with the position close to the combustion chamber (the valve stem of the intake valve) from the combustion chamber. The partition plate moves to a position distant from the target. According to the second aspect of the invention, when the valve is closed to generate a strong intake swirl flow, the partition plate is brought closer to the combustion chamber side, and when the valve is opened, the partition plate is moved away from the combustion chamber side.

According to the above construction, when the valve is closed to generate a strong swirling flow of the intake air, the partition plate is moved to a position near the combustion chamber so that the intake air is guided to the partition plate and reaches the vicinity of the combustion chamber. On the other hand, when it is not necessary to generate a strong intake swirl flow and the valve is opened, the partition plate is retracted from a position near the combustion chamber (intake valve). In the invention according to claim 3, when the valve is closed to generate a strong intake swirl flow, the partition plate is brought close to the combustion chamber side to a position near the valve stem of the intake valve, and when the valve is opened, the intake passage is partitioned by the partition plate. However, the partition plate was moved away from the combustion chamber side to a position where it was not blocked by the valve stem of the intake valve.

According to the above construction, when the valve is closed to generate a strong intake swirl flow, the partition plate is brought close to the combustion chamber side within a range that does not interfere with the valve stem of the intake valve, and when the valve is opened, the partition plate is used for partitioning. The intake passage to be blocked is not blocked by the valve stem (valve guide), and is retracted from the combustion chamber side to a position where the cross-sectional area of the intake passage partitioned by the partition plate does not change.

According to the fourth aspect of the invention, the partition plate divides the inside of the intake port into two upper and lower intake passages, one of the two upper and lower intake passages is opened and closed by a valve, and the valve is closed to make a strong tumble. It is configured to generate a flow. According to the above configuration, in the configuration in which the inside of the intake port is partitioned into upper and lower parts in order to generate a strong tumble flow in the combustion chamber, the partition plate is relatively close to the combustion chamber (the valve stem of the intake valve) and relatively away from the combustion chamber. Move to a remote location.

In the present application, the term "upper and lower" means the direction along the cylinder axis, and the cylinder head side is the upper side and the cylinder block side is the lower side. In the invention according to claim 5, the moving means moves the partition plate in conjunction with the opening / closing operation of the valve. According to the above configuration,
When closing the valve and generating a strong intake swirl flow,
The partition plate moves to the position corresponding to the valve closed state in conjunction with the valve closing operation, and when opening the valve, the partition plate moves to the position corresponding to the valve open state in conjunction with the valve opening operation. .

In a sixth aspect of the invention, the valve is a butterfly valve supported by a rotary shaft, and the moving means moves the partition plate by converting the rotary motion of the rotary shaft into a sliding motion of the partition plate. It was configured to let. According to the above configuration, when the rotary shaft rotates to open / close the butterfly valve, the rotary motion is converted into the sliding motion of the partition plate, and the partition plate slides in conjunction with the opening / closing motion of the valve.

In a seventh aspect of the invention, the moving means uses a motor as a power source for moving the partition plate. According to the above configuration, the partition plate that partitions the intake port is moved by driving the motor.

[0014]

According to the first aspect of the present invention, since the partition plate for partitioning the intake port is movable, it is located at a position suitable for generating a strong intake swirl flow and a position at which ventilation resistance can be reduced. It is possible to switch between them, and there is an effect that the engine performance in the vicinity of the fully open region can be improved while stably generating a strong intake swirl flow.

According to the second aspect of the present invention, when the valve is closed to generate a strong intake swirl flow in the combustion chamber, the partition plate is located in the vicinity of the combustion chamber, so that the intake air is reliably directed into the combustion chamber. Since it is possible to guide, it is possible to stably generate a strong intake swirl flow, while retracting the partition plate from the combustion chamber side when opening the valve, the intake valve located near the combustion chamber Avoiding that the cross-sectional area of the intake passage is extremely narrowed by the valve stem etc.,
There is an effect that it is possible to suppress an increase in ventilation resistance due to the partition plate.

According to the third aspect of the present invention, when the valve is closed to generate a strong intake swirl flow in the combustion chamber, the partition plate is positioned near the valve stem to maximize the intake swirl flow. In addition, when opening the valve, it is avoided that the intake passage partitioned by the partition plate is blocked by the valve stem (valve guide) and the passage area decreases and changes at a large rate, and the engine performance near the full open range is improved. It has the effect of improving.

According to the fourth aspect of the present invention, in the intake device which divides the intake port into two upper and lower intake passages to generate a strong tumble flow in the combustion chamber, the partition plate is moved to stabilize the strong tumble flow. There is an effect that the engine performance in the full open range can be improved while being generated. According to the invention described in claim 5, there is an effect that a mechanism for moving the partition plate can be simplified and an increase in cost due to the movable structure of the partition plate can be suppressed.

According to the invention of claim 6, the rotary motion of the rotary shaft of the butterfly valve is converted into the sliding motion of the partition plate so that the partition plate can be moved in conjunction with the valve with a simple structure. There is an effect that can be. According to the invention described in claim 7, there is an effect that the partition plate can be moved at an arbitrary timing and at an arbitrary speed.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system configuration diagram of an internal combustion engine in the embodiment. An internal combustion engine 1 shown in FIG. 1 is a cylinder direct injection gasoline engine in which a fuel injection valve 2 directly injects fuel into a combustion chamber 3.

Air metered by the throttle valve 4 is sucked into the combustion chamber 3 through the intake valve 5. The air-fuel mixture formed in the combustion chamber 3 is ignited and burned by spark ignition by the spark plug 6, and the combustion exhaust gas is discharged via the exhaust valve 7. Further, the intake port 8 is provided with a partition plate 9 for partitioning the inside of the intake port 8 into two upper and lower intake passages 8a and 8b, and an upstream end side of the partition plate 9 opens and closes a lower intake passage 8b. A tumble control valve (TCV) 10 is provided for this purpose.

When the engine 1 is operated in a lean burn mode, the TCV 10 is closed and intake air is introduced into the combustion chamber 3 from only the upper intake passage 8a, thereby generating a strong tumble flow in the combustion chamber 3. By carrying the fuel injected from the fuel injection valve 2 to the vicinity of the spark plug 6 by the tumble flow, a stratified mixture having a high air-fuel ratio around the spark plug 6 is formed, and high ignition stability at the time of lean combustion. Is obtained.

The fuel injection amount and injection timing of the fuel injection valve 2, the ignition timing of the spark plug 6, and the TC
The opening and closing of V10 is controlled by an engine control unit (ECU) 11 having a microcomputer. The ignition plug 6 has an ignition coil unit 12 with a built-in power transistor.
Is provided, and the ECU 11 controls the ignition timing of the spark plug 6 by controlling ON / OFF of the power transistor.

The partition plate 9 is slidably supported forward and backward in the extending direction of the intake port 8 and is configured to move in conjunction with the opening / closing operation of the TCV 10.
The operation mechanism (moving means) of the V10 and the partition plate 9 will be described in detail with reference to FIGS. In addition, FIG.
3B shows a state in which the TCV 10 is closed, and FIGS. 3A and 3B show a state in which the TCV 10 is opened.

The TCV 10 is fixed to a rotary shaft 21 that is rotationally driven by a motor 20, and the rotary shaft 21 that is rotatably supported with respect to the intake port 8 rotates clockwise from the state shown in FIG. 2B. When driven, it is displaced to an open position substantially parallel to the partition plate 9 as shown in FIG. 3 (B). On the other hand, the rotary shaft 2 is rotated counterclockwise from the open state shown in FIG.
1 is driven, the TCV as shown in FIG.
10 is displaced to a position that closes the intake passage 8b.

A spur gear 22 is rotatably supported at one end of the rotary shaft 21, and a spur gear 24, which is rotatably supported by a rotary shaft 23 provided in parallel with the rotary shaft 21, meshes with the spur gear 22. To be done. Further, a spur gear 26, which is rotatably supported by a rotary shaft 25 provided in parallel with the rotary shafts 21 and 23, is meshed with the spur gear 24.
In 6), when the rotary shaft 21 is rotationally driven by the motor 20, the rotary shaft 21 is driven to rotate in the same direction.

A spur gear 27 is pivotally supported together with the spur gear 26 on the rotary shaft 25. The spur gear 27 is meshed with a rack 28 provided on the upper surface of the partition plate 9,
By the meshing of the spur gear 27 and the rack 28, the rotation of the spur gear 27 is converted into the sliding movement of the partition plate 9. According to the above configuration, T shown in FIG.
When the rotary shaft 21 is rotationally driven clockwise in FIG. 2B to open the TCV 10 from the state where the CV 10 is closed, the rotary shaft 25 (spur gears 26, 27) is also rotationally driven clockwise. Then, the partition plate 9 slides leftward in FIG. 2B in conjunction with the operation of opening the TCV 10.

The right side of FIG. 2B is the combustion chamber 3 side,
Since the left side is the throttle valve 4 side, TCV10
The partition plate 9 is displaced in the direction away from the combustion chamber 3 in conjunction with the opening operation of the. On the other hand, TCV shown in FIG.
When the rotary shaft 21 is rotationally driven counterclockwise in FIG. 3 (B) to close the TCV 10 from the state where the rotary shaft 10 is opened, the rotary shaft 25 (spur gears 26, 27) is also rotated counterclockwise. The partition plate 9 is driven to rotate and interlocks with the operation of closing the TCV 10, and the partition plate 9 slides rightward in FIG. 3B, and the partition plate 9 is displaced in a direction approaching the combustion chamber 3.

The sliding amount of the partition plate 9 is determined by the spur gear 2
The TCV determined by the gear ratio of 2, 24, 26
It is determined by the rotation angle of the rotary shaft 25 with respect to the operating angle of 10 and the correlation between the rotation angle of the rotary shaft 25 and the diameter of the spur gear 27. In this embodiment, the TCV 10 is closed and the partition plate 9 is closed.
When the valve is closest to the combustion chamber 3, the tip of the partition plate 9 comes close to the valve stem 5a of the intake valve 5 (position A shown in FIG. 4).

In order to generate a strong tumble flow in the combustion chamber 3, it is required to introduce the intake air into the combustion chamber 3 in a biased manner. For that purpose, the partition plate 9 is located as close to the combustion chamber 3 as possible. It is desired that the intake air be introduced into the combustion chamber 3 from only one intake passage 8a partitioned by the partition plate 9. Therefore, when the TCV 10 is to be closed to generate a strong tumble flow, the partition plate 9 is arranged at a position close to the valve stem 5a of the intake valve 5 which is arranged so as to obliquely cross the inside of the intake port 8. Then, the partition plate 9 is made to be as close as possible to the combustion chamber 3 side.

On the other hand, when the TCV 10 is opened, the intake port 8
The intake passage 8a is provided by the valve stem 5a arranged inside.
The partition plate 9 is separated from the side of the combustion chamber 3 to a position where the passage cross-sectional area is not narrowed (position B shown in FIG. 4). During high load operation with the TCV 10 open, it is required to introduce a large amount of intake air into the combustion chamber 3. For that purpose, it is necessary to reduce the ventilation resistance as much as possible, but the partition plate 9 causes the tumble flow. When the position is close to the combustion chamber 3 which is optimum for the generation of the exhaust gas, the passage area of the intake passage 8a is extremely reduced by the valve stem 5a (valve guide 5b) (see FIG. 5), which results in a large ventilation resistance. I will.

Therefore, under the operating condition of opening the TCV 10, when it is not necessary to generate the non-uniform flow by the partition plate 9, the partition plate 9 is moved away from the combustion chamber 3 side, and the passage area of the intake passage 8a partitioned by the partition plate 9 is the valve area. The stem 5a (valve guide 5b) is prevented from being narrowed. As a result, it is possible to prevent the passage area of the intake passage 8a from decreasing and changing at a large rate to result in a large ventilation resistance, and it is possible to improve engine performance particularly near the fully open region.

In the above embodiment, the TCV10
Although the partition plate 9 is configured to move in conjunction with the opening / closing operation of, the partition plate 9 may be driven independently of the opening / closing operation of the TCV 10. FIG. 6 (A),
(B) shows a second embodiment provided with moving means for independently driving the partition plate 9.

In FIGS. 6A and 6B, TCV1
Separately from the actuator that drives 0 to open and close,
A dedicated motor 31 for slidingly driving is provided. The motor 31 is drive-controlled by the ECU 11, and is arranged so that its rotation shaft 31 a is orthogonal to the end surface of the partition plate 9. A worm wheel 32 is rotatably supported by a rotary shaft 31a of the motor 31, and the worm wheel 32 has a rotary shaft 33 parallel to the end surface of the partition plate 9 and parallel to the radial direction of the intake port 8. The worm gear 34 provided in the gear is engaged with the rotation shaft 33 by the rotation of the motor 31.

A spur gear 35 is rotatably supported on the rotary shaft 33, and the spur gear 35 is meshed with a rack 36 provided on the upper surface of the partition plate 9 so that the spur gear 35 and the rack 36 are connected to each other. By the meshing, the rotation of the spur gear 35 is converted into the sliding movement of the partition plate 9.
Also in the above configuration, basically, when the TCV 10 is to be closed to generate a strong tumble flow, the partition plate 9 is brought closer to the combustion chamber 3 side, and when the TCV 10 is opened, the partition plate 9 is moved from the combustion chamber 3 side. Try to keep them away.

However, since the partition plate 9 can be driven independently of the opening and closing of the TCV 10, for example, even when the same TCV 10 is open, the partition plate 9 is positioned near the combustion chamber 3 when the engine load is relatively small. The partition plate 9 may be gradually moved away from the combustion chamber 3 as the engine load increases, and may be moved to a position where the passage area of the intake passage 8a is not narrowed by the valve stem 5a near the full load. However, in the same manner, the position of the partition plate 9 can be changed with the TCV 10 closed.

Further, in the structure in which the partition plate 9 is moved to either of two positions, the movement start timing of the partition plate 9 is shifted with respect to the opening / closing operation of the TCV 10, and further, the moving speed of the partition plate 9 is controlled. It is possible. In the above-described embodiment, the lower intake passage 8b of the intake passages 8a and 8b divided into the upper and lower parts by the partition plate 9 is closed, but the upper intake passage 8a is closed by the TCV 10. The configuration may be such that a tumble flow in the opposite direction is generated.

Further, in a structure in which the intake port 8 is partitioned into left and right by a partition plate and one of the intake passages is closed by a valve (swirl control valve), a strong swirl flow is generated in the combustion chamber. You may make it move to the front and back of the installation direction.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an internal combustion engine in an embodiment.

FIG. 2 is a diagram illustrating a T in the first embodiment of the partition plate moving means.
It is a figure which shows the closed state of CV, (A) is a front view, (B)
Is a side view.

FIG. 3 is a diagram showing an open state of the TCV in the first embodiment, (A) is a front view and (B) is a side view.

FIG. 4 is a schematic diagram for explaining a positional change of a partition plate in the embodiment.

FIG. 5 is a cross-sectional view of the intake port showing the positional relationship between the partition plate and the valve stem in the embodiment.

6A and 6B are views showing a second embodiment of a partition plate moving means, in which FIG. 6A is a front view and FIG. 6B is a side view. DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine 2 ... Fuel injection valve 3 ... Combustion chamber 5 ... Intake port 5a ... Valve stem 5b ... Valve guide 8 ... Intake ports 8a, 8b ... Intake passage 9 ... Partition plate 10 ... Tumble control valve (TCV) 11 ... Engine Control unit (ECU) 20 ... Motors 22, 24, 26, 27 ... Spur gear 28 ... Rack 31 ... Motor 32 ... Worm wheel 34 ... Worm gear 35 ... Spur gear 36 ... Rack

Claims (7)

[Claims] 1. A combustion system comprising: a partition plate for partitioning an intake port into a plurality of intake passages; and a valve for opening and closing a part of the plurality of intake passages partitioned by the partition plate. An intake device for an internal combustion engine, which generates a strong intake swirl flow in a room, comprising: a moving means for moving the partition plate forward and backward in a direction in which an intake port extends. 2. The partition plate is brought closer to the combustion chamber side when a strong intake swirl flow is generated by closing the valve, and the partition plate is moved away from the combustion chamber side when the valve is opened. An intake system for an internal combustion engine according to claim 1. 3. When a strong intake swirl flow is generated by closing the valve, the partition plate is brought close to the combustion chamber side to a position near the valve stem of the intake valve, and when the valve is opened, the partition plate is partitioned. The intake device for an internal combustion engine according to claim 2, wherein the partition plate is moved away from the combustion chamber side to a position where the intake passage is not blocked by the valve stem of the intake valve. 4. The partition plate divides the inside of the intake port into two upper and lower intake passages, and the valve opens and closes either one of the upper and lower intake passages partitioned by the partition plate, and closes the valve. As a result, a strong tumble flow is generated in the combustion chamber, and the intake system for an internal combustion engine according to claim 1, wherein the tumble flow is strong. 5. The intake system for an internal combustion engine according to claim 1, wherein the moving means moves the partition plate in conjunction with the opening / closing operation of the valve. 6. The butterfly valve, wherein the valve is supported by a rotary shaft, and the moving means converts the rotary motion of the rotary shaft into a sliding motion of the partition plate to move the partition plate. The intake system for an internal combustion engine according to claim 5, wherein: 7. The intake system for an internal combustion engine according to claim 1, wherein the moving means uses a motor as a power source for moving the partition plate.