JPH09119317A - Intake controller for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve combustion at low-load low-speed to medium-load medium- speed and combustion stability, and provide large torque at the time of high-load high-speed. SOLUTION: In an intake device for internal combustion engine, which is mounted on a multiple-valve type engine and consists of a main intake passage 1, a plurality of sub intake passages 3-1 to 3-4 and an intake passage control valve 2, the upstream end parts 3-1a, 3-2a, 3-3a, 3-4a of the sub intake passages 3-1 to 3-4 are disposed at different positions so that the number of the sub intake passages 3-1 to 3-4 which permit intake to be passed according to the opening of an intake passage control valve 2 may be changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake control device for an internal combustion engine.

[0002]

2. Description of the Related Art As a conventional intake air control device for an internal combustion engine, there is, for example, one disclosed in Japanese Patent Laid-Open No. 5-39725.

[0003]

In such an intake control device for a conventional internal combustion engine, the swirl is formed in the combustion chamber by supplying intake air through the auxiliary intake passage at low load and low rotation speed. As a result, good combustion was enabled by the combustion improving effect, but at the time of high load and high speed, a sufficient amount of intake air could not be sent to the combustion chamber, and the required torque could not be obtained. Further, since the auxiliary passage having a diameter smaller than that of the main intake passage is used, there are problems that clogging due to deposition of depots occurs and it is difficult to process the auxiliary intake passage.

The present invention has been made by paying attention to the above-mentioned conventional problems, and aims to improve the combustion and the combustion stability at low load low rotation to medium load medium rotation, and at the time of high load high rotation. A first object is to make it possible to obtain a large torque, and a second object is to prevent clogging in the auxiliary intake passage and improve workability.

[0005]

In order to achieve the above first object, in the invention according to claim 1, in a multi-valve engine having an intake valve and an intake passage for one cylinder, a main intake passage and a plurality of intake passages are provided. In the intake system for an internal combustion engine, which comprises the auxiliary intake passage and the intake passage switching valve, the number of auxiliary intake passages is changed by controlling the intake passage switching valve, and the intake flow rate and the intake direction are controlled. did.

The intake passage switching valve is
The intake control valve may be configured to rotate about the valve shaft, an arc-shaped inner wall with which the intake control valve abuts, and a passage opening to the inner wall (claim 2). Further, the intake passage switching valve may be controlled so that a tumble flow is formed during low load operation and a swirl flow is formed during medium load operation (claim 3).

Further, in order to achieve the above-mentioned second object, in the invention according to claim 4, the sub intake passage is constituted by a groove.

[0008]

According to the present invention, the intake amount is not insufficient by having a plurality of auxiliary intake passages and changing the number of intake passages in accordance with the required intake amount of the engine. The flow velocity of the intake air can be made constant in order to obtain a constant number, and stable swirl and tumble can be obtained, good combustion can be obtained at both low air amount and high air amount, and a groove is used as a sub passage. However, clogging due to depots, which has been a problem in the past, is solved by being washed with fuel, and since a groove is used as a sub passage, processing is easier than with a sub passage such as a pipe.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. 1 and 2 are diagrams showing a first embodiment of the present invention. First, the structure will be described. Reference numeral 1 is a main intake passage for sending intake air into the engine combustion chamber, and 2 is an intake passage control valve provided upstream of the main intake passage 1. 3-1 to 3-4 are sub intake passages provided in the main intake passage 1 in a groove shape. The intake air passing through the auxiliary intake passage 3 is controlled by the intake passage control valve 2. Reference numeral 4 is a fuel injection valve for supplying fuel to intake air passing through the main intake passage 1, 5 is a combustion chamber for burning the intake air-fuel mixture, 6a and 6b are intake valves, and 7 is intake into the combustion chamber 5. It is a spark plug that spark-ignites a mixture. 8
Is the intake port.

Reference numeral 9 is an intake control valve, which rotates around a valve shaft 10. The intake passage inner wall 12 with which the end portion 9a of the intake control valve 9 abuts has a substantially arcuate cross section as shown in FIG.

The upstream side ends of the sub intake passages 3-1 to 3-4 are located on the arc-shaped intake passage inner wall 12.

In this embodiment, the main intake passage 1 forms a so-called Siamese type intake passage in which the main intake passage 1 branches into two intake ports 8a and 8b on the downstream side.

Next, the operation of the embodiment will be described. When the amount of intake air required by the engine is small, such as in an idle state or under low load and low rotation, the intake control valve 9 is closed and air does not flow into the main intake passage 1 and is sucked into only the sub intake passages 3-1 to 3-4. Allow the air to flow. At this time, the intake control valve 9 is fully closed (position in FIG. 1), and the upstream end portions 3-1a and 3-4a of the auxiliary intake passages 3-1 and 3-4 are located upstream of the intake control valve 9. Since the auxiliary intake passages 3-2 and 3-3 are located on the downstream side, intake air is supplied to the combustion chamber 5 through the auxiliary intake passages 3-1 and 3-4. The intake air supplied by the auxiliary intake passages 3-1 and 3-4 has directivity and a constant flow velocity while passing through the auxiliary intake passages 3-1 and 3-4, and the auxiliary intake passages 3-1 and 3-4.
Even if it goes out, it enters the combustion chamber 5 without diffusion and forms a strong vertically oriented vortex (tumble) in the combustion chamber 5 to improve the combustibility.

Next, when the required intake air amount of the engine becomes large at the time of medium load, medium rotation, etc., the intake control valve 9 is opened. At this time, the intake control valve 9 is an actuator (not shown), and the opening degree is controlled by calculating the required intake air amount by an ECU (engine control unit) from the accelerator rotation rate, the signal of the air flow meter, and the like. Then, the auxiliary intake passages 3-2 and 3-3 which have been closed until now are communicated. First, the upstream end 3-2a of 3-2 comes to be located on the upstream side of the intake control valve 9, and the intake control valve 9
When is opened, intake can be performed without causing intake resistance even if the intake flow rate increases for this reason. In this embodiment, the auxiliary intake passages 3-2 and 3-3 at the time of high flow rate are attached only to the intake port 8a on one side. Therefore, when the intake control valve 9 is closed, the flow of the air-fuel mixture in the combustion chamber 5 is increased. Is only the tumble flow A (see FIG. 1) formed by the auxiliary intake passages 3-1 and 3-4, and the intake flow in the combustion chamber 5 opens the intake control valve 9 to open the auxiliary intake air. Passage 3
-2, 3-3 increases the amount of intake air flowing into the combustion chamber 5 from the intake port 8a side, so that a strong lateral swirl (swirl) B (see FIG. 2) can be formed to improve combustion stability. I can.

In this way, the intake control valve 9 is controlled according to the required intake amount of the engine as shown in FIG. 5, is connected to the auxiliary intake passages 3-1 to 3-4, and is controlled by the intake control valve 9. The intake air whose flow path has been switched is the auxiliary intake passage 3-1 to 3-3.
-4, flowing into the combustion chamber 5 with directivity and a constant flow velocity. As a result, tumble and swirl are formed in the combustion chamber 5 in accordance with the opening degree of the intake control valve 9. Combustion can be improved by tumble and combustion stability can be improved by swirl.

At this time, by making the auxiliary intake passages 3-1 to 3-4 for forming swirls and tumbles blues without using pipes or the like, the accumulation of depots and the clogging due to depots are eliminated by being exposed to the fuel, which causes a problem. Occurs, and the intake air flows at a high flow rate in the groove, so that a negative pressure occurs in the groove and the mist fuel is sucked into the flow and is effectively filled in the combustion chamber 5, so that the fuel injection valve 4 The fuel injected from is not left in the intake passage, and the wall flow can be reduced. Also, considering workability, it can be easily molded because it can be integrally formed with the main intake passage 1, and the main intake passage 1 and the auxiliary intake passages 3-1 to 3-4 are integrated, so that the layout is also Easy to do.

Further, at the time of high rotation and high load operation, the intake control valve 9 is further opened, and the end portion 9a thereof comes out from the arc-shaped portion of the inner wall 12 of the intake passage. The main intake passage 1 becomes the main flow rather than 3-4, a large amount of intake air can be supplied to the combustion chamber 5, and a desired large output of the engine can be generated.

Next, a second embodiment shown in FIG. 3 will be described. In the second embodiment, the auxiliary intake passages 3-1 to 3-3 are set to 1
By providing only one intake port 8a, at the time of high load / high rotation, the intake control valve 9 comes out of the arc-shaped intake passage inner wall 12 to form a tumble, and in other cases, the auxiliary intake passage 3 is formed. The tumble and swirl are simultaneously formed by the intake air from -1 to 3-3, and the combustion stability can be obtained by both effects.

Next, a third embodiment shown in FIG. 4 will be described.

In the third embodiment, the auxiliary intake passages 3-1 to 3-6
By arranging three of them symmetrically toward each intake port 8a, 8b, the effect of combustion improvement by tumble can be obtained from the low load low rotation range to the high load rotation range. As a result, the air-fuel ratio can be made leaner than when the auxiliary intake passages 3-1 to 3-6 are not used, and fuel consumption can be suppressed to a low level.

[0021]

As described above, according to claims 1 to 3.
According to the invention described in (1), the configuration is such that it has a plurality of auxiliary intake passages and is controlled by the intake passage control valve to switch the auxiliary intake passages according to the required intake air amount of the engine. Tumble and swirl are formed at the time of rotation, and the effects of combustion improvement and combustion stability can be obtained.

According to the fourth aspect of the invention, since the sub-intake passage is not a pipe or the like but is a groove, it is possible to eliminate problems such as clogging due to depots, reduce the wall flow of the intake port, and facilitate machining. can get.

[Brief description of the drawings]

FIG. 1 is a structural explanatory view of a first embodiment viewed from above.

FIG. 2 is a structural explanatory view as seen from a side surface of the first embodiment.

FIG. 3 is a structural explanatory view of the second embodiment viewed from above.

FIG. 4 is a structural explanatory view of the third embodiment viewed from above.

FIG. 5 is a diagram showing a relationship between a required intake air amount and an intake passage control valve opening degree.

[Explanation of symbols]

 1 main intake passage 2 intake passage control valve 3-1 to 3-6 sub-intake passage 4 fuel injection valve 5 combustion chamber 6 intake valve 7 spark plug 8 intake port 9 intake control valve 12 intake passage inner wall

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Mori 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd.

Claims (4)

[Claims] 1. An intake system for an internal combustion engine comprising a main intake passage, a plurality of auxiliary intake passages, and an intake passage switching valve in a multi-valve engine having an intake valve and an intake passage for one cylinder. By controlling the valve,
An intake control device for an internal combustion engine, characterized in that the number of auxiliary intake passages is changed to control the intake flow rate and the intake direction. 2. The intake passage switching valve is constituted by an intake control valve that rotates about a valve shaft, an arc-shaped inner wall with which the intake control valve abuts, and a passage that opens into the inner wall. The intake control device for an internal combustion engine according to claim 1, characterized in that: 3. The intake passage switching valve is controlled so that a tumble flow is formed during low load operation and a swirl flow is formed during medium load operation. Intake control device for internal combustion engine. 4. The intake control device for an internal combustion engine according to claim 1, wherein the auxiliary intake passage is formed by a groove.