JPH10246161A - Intake device of engine for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device attaining improvement of performance of an engine simultaneously with reducing an intake noise, in an intake system in the engine of an automobile. SOLUTION: Respectively an in/out hose 7, 4 of an air cleaner 3 in an intake system of an engine of an automobile is made to branch in a plurality of passages 7a, 7b, 4a, 4b, in one passage 7b, 4b thereof, respectively a valve 11, 12 is interposed. Corresponding to a rotational speed of the engine, by combining opening/closing of the valve 11, 12, reduction of intake noise and improvement of engine performance can be attained.

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 automobile engine, which reduces intake noise and improves engine performance in an automobile engine.

[0002]

2. Description of the Related Art An automobile engine draws air around the engine, introduces a mixture obtained by adding a predetermined ratio of fuel to the combustion chamber, and explodes it in a compressed state to generate energy. Although the intake of air and the release of exhaust are performed in a fixed cycle, an intake noise generated when inhaling air may be annoying, and a resonator has conventionally been used to eliminate the intake noise.

FIG. 14 shows a prior art of an intake system for an automobile engine using a resonator. This will be described. Reference numeral 1 denotes an intake manifold, and a branched pipe 1a is connected to a combustion chamber of an engine (not shown). Since the illustrated one is for three cylinders, there are three branch pipes 1a. The base of the intake manifold 1 is connected to the tip of an out hose 4 of an air cleaner 3 via a throttle body 2. Reference numeral 5 denotes a throttle valve which rotates inside the throttle body 2 to change the opening of the passage.

[0004] A base end of an out hose 4 of the air cleaner 3 is connected to an outlet 3 a of the air cleaner 3. Reference numeral 6 denotes a cleaner element of the air cleaner 3.
One end of an in hose 7 of the air cleaner 3 is connected to an inlet 3b of the air cleaner 3. The other end (the right end in the figure) of this in-hose 7 is open to the atmosphere,
The resonator 8 is connected to the middle part in a branched state. The arrows in the figure indicate the direction in which air flows.

[0005]

In such a structure, when air flows in the direction indicated by the arrow when the throttle valve 5 is opened when the throttle valve 5 is opened, a part of the flowing air enters the resonator 8, and this flows into the resonator 8. A noise-reducing effect is achieved by canceling the vibration by resonating with the vibration of the air flowing outside the unit 8. If the resonator 8 is provided, it is possible to effectively attenuate the intake sound as described above. However, only the silencing effect can be obtained, and it does not contribute to the other purpose, that is, to improve the performance of the engine at all. Things.

Further, since the volume of the resonator 8 is constant and cannot be changed, the sound that can be silenced by resonance is a single frequency, and cannot respond to sounds of a plurality of frequencies. To support sounds of multiple frequencies,
The number of the resonators 8 must be provided. Further, since the resonator 8 is generally a separate part from other members of the intake system, providing such a part increases the cost of parts and the cost of assembly.

The related art of the present invention is disclosed in
No. 7028 and JP-A-4-8861. In the former, two first and second ducts are provided on the upstream side of the air cleaner, and one of the ducts is provided with a flow control valve, and two surge tanks provided in an intake system of the engine are connected. Connect in the aisle,
This communication passage is also provided with a valve. By changing the opening of the flow control valve and valve with this configuration,
The intake noise is reduced in accordance with a change in the engine speed.

In the latter, a partition wall extending longitudinally from one end side is provided in an intake duct connected to an air cleaner, and the partition wall divides two main and sub passages into a duct. This is a configuration in which one valve that opens and closes the sub-passage in accordance with the operating state of the engine is provided in the passage. In this configuration, the resonance of the duct is eliminated by changing the opening degree of the valve.

[0009]

It can be recognized that the above two publications have a great effect on reducing or eliminating the intake noise. The present invention has been made based on these techniques and further improved to provide an intake device for an automobile engine capable of effectively eliminating intake noises of more frequencies than those in the above publication. is there.

[0010]

According to the present invention, as a means for solving the above problems, in the invention described in claim 1, each of an in-hose and an out-hose of an air cleaner in an intake system of an automobile engine is provided. In addition to branching into a plurality of passages, separate valves are provided in some of the plurality of passages on the upstream and downstream sides of the air cleaner, and each of the valves is controlled to open and close. And

According to a second aspect of the present invention, in the first aspect, a control device for appropriately opening and closing valves provided on an upstream side and a downstream side of the air cleaner is provided. A sound reduction function corresponding to a plurality of frequencies is provided by changing the combination of opening and closing of the valve.

[0012]

FIG. 1 is a block diagram showing an embodiment of the present invention.
In the following description, the same parts as those in FIG. The major feature of the present invention is that the air cleaner 3
In the inside of each of the in hose 7 and the out hose 4, branch plates 9 and 10 are provided in the longitudinal direction, and the inside of the in hose 7 and the out hose 4 is divided by the branch plates 9 and 10 into a plurality of passages 7a, 7b, 4a and 4b. And valves 11 and 12 are provided in some of the passages 7b and 4b,
That is, the valves 11 and 12 are controlled to open and close, respectively. In this case, the effective cross-sectional area of the in hose 7 and the out hose 4 is the sum of the branched passages 7a, 7b and the passages 4a, 4b.

The operation of the intake device of the present invention having the above-described structure will be described with reference to FIGS. The two valves 11 and 12 are controlled by a control device (not shown) so as to open or close. The opening does not reach the middle position. The state shown in FIG.
This is a case where both of the two valves 11 and 12 are closed. Such control is performed when the engine speed is lower than a certain engine speed A in FIG. 3 indicating that both the valves 11 and 12 are closed (low-speed engine speed range), and the noise level at that time is as shown in FIG. This is shown in a portion lower than the frequency a.

At this time, neither the passage 7b of the in-hose 7 nor the passage 4b of the out-hose 4 functions as a passage, and air flows to the throttle body 2 only through the passages 7a and 4a. By closing the two valves 11, 12, the passages 7b, 7b,
The length L ₁ in 4b, L _2, L ₃ of the chamber 13, 14, 15 are formed, all of these will function as a resonator.

FIG. 4 shows the relationship between the frequency of the intake sound and the noise level. The curve shown by a solid line shows the characteristic when both valves 11 and 12 are closed, and the curve shown by a broken line. Shows the characteristics when the two valves 11 and 12 are both opened. In this figure and the following figures, a represents the noise level characteristic when the engine speed is A, and L ₁ <L ₃ <L _2, and X represents the length L _2.
The characteristic portion of the chamber 14, Y is a characteristic portion of the chamber 13 length L _1, and further Z represents a characteristic portion of the chamber 15 of length L _3.

In the state shown in FIG. 5, the valve 12 is opened and the valve 11 is closed. Such control is performed when the engine speed is between A and B as shown in FIG. 6 (medium speed rotation range). The curves shown in FIG. 6 and FIG. 12 described later are the characteristics when both the valves 11 and 12 are closed. The noise level at this time is as shown by hatching in FIG. At this time, the air that has exited the air cleaner 3 enters the intake manifold 1 through both the passages 4a and 4b. At this time, only the chamber 15 functions as a resonator.

In the state shown in FIG. 8, the valve 12 is closed and the valve 11 is opened. Such control is performed when the engine speed is between B and C as shown in FIG. 9 (a place slightly higher than the middle speed range). The noise level at this time is as shown by hatching in FIG. At this time, the air entering the air cleaner 3 enters the air cleaner 3 through both the passages 7a and 7b of the in-hose 7. The air flowing out of the air cleaner 3 enters the intake manifold 1 only through the passage 4a of the out hose 4. At this time, the chambers 13 and 14 function as resonators.

In the state shown in FIG. 11, both valves 11 and 12 are opened so that the function of the resonator is not obtained. In such control, the engine speed is controlled as shown in FIG.
As shown in (2), it is performed at a time higher than C (high-speed rotation range). The noise level at this time is as shown by hatching in FIG.

As described above, the opening and closing control of the valves 11 and 12 is performed in accordance with the engine speed. Since the output of the engine and the frequency of the intake sound change in relation to the engine speed, the chambers 13, 14, 15 formed by the valves 11, 12 which are closed corresponding to the engine speed.
(See FIG. 2) The volume (opening areas of the passages 7b and 4b and the positions of the valves 11 and 12) is appropriately set to change the number of rotations tuned to the engine, and the number of rotations generating torque changes. In addition to improving the performance of the engine, both the valves 11 and 12 are closed at low and medium speeds to enhance the resonator function.
At high speeds, both valves 11 and 12 are opened to increase the amount of intake air and increase the output.

In the embodiment described above, each of the in hose and the out hose of the air cleaner is branched into two passages, and a valve is provided in each of the two passages. However, the present invention is not limited to this. Instead, the number of passages may be further increased, and the number of valves and the installation position may be changed. The point is that while part of the intake system functions as a resonator, valves are provided on the upstream and downstream sides of the air cleaner, and their opening and closing are controlled appropriately, so that engine performance can be improved and intake noise can be reduced. It is good to do.

[0021]

Since the present invention is an intake device for an automobile engine configured as described above, by controlling the opening and closing of a plurality of valves as appropriate, it is possible to improve both engine performance and reduce intake noise. And a plurality of resonance frequencies can be handled by opening and closing combinations of valves. Further, since it is not necessary to use a resonator as a dedicated component, the cost can be reduced.

[Brief description of the drawings]

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

FIG. 2 is an explanatory diagram for explaining an operation of the device of FIG. 1;

FIG. 3 is a graph showing an engine speed when a valve is controlled to the state shown in FIG. 2;

FIG. 4 is a graph showing a noise level when the valve is controlled to the state shown in FIG. 2;

FIG. 5 is a sectional view showing a state where the valve is in a different state.

6 is a graph showing the engine speed when the valve is controlled to the state shown in FIG. 5;

FIG. 7 is a graph showing a noise level when the valve is controlled to the state shown in FIG. 5;

FIG. 8 is a cross-sectional view showing a state where the valve is in a different state.

FIG. 9 is a graph showing the engine speed when the valve is controlled to the state shown in FIG. 8;

FIG. 10 is a graph showing a noise level when the valve is controlled to the state shown in FIG. 8;

FIG. 11 is a cross-sectional view showing a state where the valve is in a further different state.

FIG. 12 is a graph showing the engine speed when the valve is controlled to the state shown in FIG. 11;

FIG. 13 is a graph showing a noise level when the valve is controlled to the state shown in FIG. 11;

FIG. 14 is a cross-sectional view showing a conventional art of an intake device for an automobile engine using a resonator.

[Explanation of symbols]

 Reference Signs List 1 intake manifold 3 air cleaner 4 out hose 4a passage 4b passage 7 in hose 7a passage 7b passage 9 branch plate 10 branch plate 11 valve 12 valve

Claims (2)

[Claims] 1. An air cleaner according to claim 1, wherein each of an inlet hose and an outlet hose of an air cleaner in an intake system of an automobile engine is branched into a plurality of passages, and a part of the plurality of passages is provided upstream and downstream of the air cleaner. An intake device for an automobile engine, wherein a separate valve is provided, and each of the valves is controlled to open and close. 2. A noise reduction function corresponding to a plurality of frequencies is provided by providing a control device for appropriately opening and closing valves provided on an upstream side and a downstream side of the air cleaner, and changing a combination of opening and closing of the valves by the control device. The intake device for an automobile engine according to claim 1, wherein the intake device is provided.