JP2004332673A - Intake noise reduction device for vehicular internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake noise reduction device for a vehicular internal combustion engine capable of reducing intake noise without reducing engine torque. <P>SOLUTION: In the intake noise reduction device for the vehicular internal combustion engine provided with an intake duct 3 supplying air to an air cleaner, an intake noise reduction member 6 composed of a main body part 6a formed in a roughly cylindrical shape, an opening part 6c formed on an outer circumference of the main body part 6a and sound absorbing material 6d provided to face the opening part 6c is inserted in the intake duct 3. Consequently, since the intake noise reduction member 6 constructed as a separate member is inserted in the intake duct 3, airtightness of the intake duct 3 is improved as compared with a case of forming the opening part on the intake duct 3 main body and intake noise can be reduced without reducing engine torque. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an intake noise reduction device for a vehicle internal combustion engine.
[0002]
[Prior art]
Conventionally, in a vehicle internal combustion engine, a pressure wave generated due to opening and closing of an intake valve is transmitted through an intake pipe and an air cleaner to an air intake of an air duct which introduces air to an air cleaner at the most upstream end of an intake system. There is a problem that an uncomfortable intake sound is generated for the occupant due to the propagation or the like.
[0003]
Therefore, Patent Document 1 below discloses that a plurality of small holes are opened on the outer periphery of an intake duct, and the small holes are covered with a sound absorbing material to reduce intake noise.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-282895 [Problems to be Solved by the Invention]
[0005]
However, according to Patent Literature 1 described above, since the opening is formed on the outer periphery of the intake duct, the degree of sealing in the intake duct is reduced, and intake loss may occur, and engine torque may be reduced.
[0006]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an intake noise reduction device for a vehicle internal combustion engine capable of reducing intake noise while suppressing a decrease in engine torque. Is to do.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides the following as a solution. That is, in the first configuration of the present invention, in the intake noise reduction device for a vehicle internal combustion engine including an intake duct that supplies air to an air cleaner, the intake duct includes a main body formed in a substantially cylindrical shape, An intake noise reduction member including an opening formed on the outer periphery of the main body and a sound absorbing material provided to face the opening is inserted.
According to the first configuration of the present invention, since the opening is formed in the intake noise reduction member that is configured as a member separate from the intake duct, the intake duct is not provided with respect to the case where the opening is formed in the intake duct body. The degree of sealing is improved, and intake noise can be reduced while suppressing a decrease in engine torque.
[0008]
In the second configuration of the present invention, a funnel-shaped suction portion whose diameter is increased toward the air intake side of the intake duct is formed in the main body portion, and the opening is formed from the main body portion to the suction portion. It is constituted so that it may be formed over.
Here, in order to enhance the intake noise reduction effect, it is desirable to form an opening and provide an intake sound material in the air intake opening at the tip of the intake duct. This is because the air intake, which is the tip of the intake duct, is a position that serves as a node for pressure waves of all frequencies of the intake sound, so that all frequencies can be silenced.
However, if the opening is simply formed in the vicinity of the air intake of the intake duct, the wall pressure of the intake duct near the air intake becomes thin, and the rigidity of the intake duct may be reduced.
According to the second configuration of the present invention, since the opening is formed in the intake noise reducing member formed as a member separate from the intake duct, noise reduction of all frequencies is achieved while securing the rigidity of the intake duct itself. be able to.
In addition, since a funnel-shaped suction portion having an enlarged diameter is formed on the air intake side of the main body of the intake noise reducing member, the position of the node of the pressure wave is closer to the air cleaner than the intake duct air intake. In this case, the position of the opening can be shifted to the air cleaner side from the intake duct air intake port.
Therefore, since the opening position of the opening formed in the intake noise reduction member can be shifted toward the air cleaner side from the front end side, the thickness near the air intake can be secured, and the rigidity of the intake noise reduction member can be improved. It is possible to silence all the frequencies while securing.
[0009]
【The invention's effect】
According to the present invention, intake noise can be reduced while suppressing a decrease in engine torque.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 is an overall view showing an intake system upstream of a surge tank of an engine, FIG. 2 is a side view of an intake duct, and FIG. 3 is a side view of an intake noise reducing member.
In this embodiment, an example in which the present invention is applied to a 4-cylinder in-line gasoline engine will be described.
[0011]
In FIG. 1, reference numeral 1 denotes an intake pipe whose downstream end is connected to a surge tank (not shown), 2 denotes an air cleaner, 3 denotes a resin intake duct, and 4 and 5 deactivate intake sounds of different frequencies. Is an intake noise reduction member inserted into the intake duct 3.
[0012]
As shown in FIG. 2, the intake duct 3 has an air cleaner connecting portion 3a connected to the air cleaner 2 at one end and an air intake 3b for taking in air at the other end. Have been.
[0013]
In addition, an intake sound reducing member 6 to be described later is inserted into a straight portion 3c formed on the side of the air intake 3a of the intake duct 3.
The intake noise reduction member 6 is inserted such that one end thereof is in contact with the throttle portion 3d of the intake duct 3 and the other end is in contact with the inner periphery of the air intake 3b.
At this time, the inner diameter d1 of the intake duct 3 in the straight portion 3c is formed to be larger than the inner diameter d2 of the intake duct 3 other than the straight portion 3c, while the inner diameter d3 of the intake sound reducing member 6 is larger than the inner diameter d other than the straight portion 3c. d2, and has the same inner diameter from the air cleaner connecting portion 3a of the intake duct 3 to the air intake 3b even when the intake noise reducing member 6 is inserted into the intake duct 3. The diameter will be maintained.
[0014]
As shown in FIG. 3, the intake sound reducing member 6 includes a resin-made main body 6 a formed in a cylindrical shape, and the air in the intake duct 3 when the main body 6 a is inserted into the intake duct 3. A funnel-shaped suction portion 6b whose diameter is gradually increased from the main body portion 6a on the side located on the side of the intake port 3b, and a longitudinal direction extending over the entire outer circumference of the main body portion 6a and the entire outer circumference of the suction portion 6b. And a sound absorbing material 6d made of a porous fiber material such as a nonwoven fabric covering the opening 6c from the inner peripheral side of the main body 6a and the suction portion 6b. Have been.
[0015]
As described above, according to the present embodiment, since opening 6c is formed in intake noise reduction member 6 configured as a member separate from intake duct 3, opening 6c is formed in the intake duct 3 main body. In comparison with the case, the degree of sealing of the intake duct 3 is improved, and intake noise can be reduced while suppressing a decrease in engine torque.
Further, since the opening 6c is formed over the main body 6a of the intake noise reducing member 6 and the intake portion 6b, which are formed as members separate from the intake duct 3, the intake duct 3 and the intake noise reducing member 6 Silencing of all frequencies can be achieved while securing rigidity.
Further, since a funnel-shaped suction portion 6b having an enlarged diameter is formed on the air intake side of the main body portion 6a of the intake sound reducing member 6, the position of the node of the pressure wave is determined by the air intake of the intake duct 3. The opening 6c can be formed so as to be shifted toward the air cleaner 2 from the opening 3b and the opening 6c is shifted toward the air cleaner 2 from the air intake 3b of the intake duct 3.
Therefore, the opening position of the opening 6c formed in the intake noise reducing member 6 can be shifted to the air cleaner 2 side from the tip end side. Silence can be achieved.
The inner diameter d1 of the intake duct 3 in the straight portion 3c is formed to be larger than the inner diameter d2 of the intake duct 3 other than the straight portion 3c, while the inner diameter d3 of the intake sound reducing member 6 is smaller than the inner diameter d2 other than the straight portion 3c. Even when the intake noise reducing member 6 is inserted into the intake duct 3, the inner diameter of the intake duct 3 from the air cleaner connection portion 3a to the air intake 3b is the same. Will be maintained.
Accordingly, when the intake noise reducing member 6 is inserted into the intake duct 3, intake resistance can be reduced, and a decrease in engine torque can be suppressed.
[0016]
According to the present embodiment, an example in which the opening 6c is formed over the main body 6a and the suction section 6b has been described. However, as shown in FIG. 4, the opening 6c is formed only on the main body 6a. You may make it.
[0017]
Further, according to the present embodiment, the example in which the shape of the opening 6c is substantially rectangular is shown, but the opening 6c may be formed in a circular shape as shown in FIG.
[0018]
Further, in the present embodiment, an example in which the invention is applied to a four-cylinder in-line type engine has been described. However, the invention may be applied to a gasoline engine having a number of cylinders other than four or a diesel engine.
[Brief description of the drawings]
FIG. 1 is an overall view showing an intake system upstream of a surge tank of an engine according to an embodiment of the present invention.
FIG. 2 is a side view of the intake duct according to the embodiment of the present invention.
FIG. 3 is a side view of the intake noise reducing member according to the embodiment of the present invention.
FIG. 4 is a side view of an intake noise reducing member according to another embodiment of the present invention.
FIG. 5 is a side view of an intake noise reducing member according to another embodiment of the present invention.
[Explanation of symbols]
1: intake pipe 2: air cleaner 3: intake duct 3a: air cleaner connection 3b: air intake 6: intake sound reducing member 6a: main body 6b: suction section 6c: opening 6d: sound absorbing material.

Claims (2)

In an intake noise reduction device for a vehicle internal combustion engine having an intake duct for supplying air to an air cleaner,
The intake duct has an intake sound reducing member including a substantially cylindrical main body, an opening formed on the outer periphery of the main body, and a sound absorbing material provided to face the opening. An intake noise reduction device for an internal combustion engine for a vehicle, characterized in that the intake noise reduction device is inserted. In the main body, a funnel-shaped suction portion having an enlarged diameter on the air intake side of the intake duct is formed,
2. The intake noise reduction device for an internal combustion engine for a vehicle according to claim 1, wherein the opening is formed from the main body to a suction portion.

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