JP2009047155A - Suction noise regulating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suction noise regulating device capable of achieving both of securing of the calmness and boosting the suction noise. <P>SOLUTION: The suction noise regulating device 1 is equipped with a communication pipe 4 attached to the peripheral surface of a clean side suction duct 14 constituting a suction passage to an engine for communicating with the clean side suction duct 14, and a resilient piece 6 choking the communication pipe 4 and vibrating in the extra-surface direction while it makes elastic deformation in response to a suction pulsation generated inside the clean side suction duct 14, wherein the arrangement further includes a flow passage area changing means 8 to change the flow passage area of the communication pipe 4 owing to a change in the engine side suction negative pressure among the suction negative pressure generated inside the clean side suction duct 14, the engine side suction negative pressure being generated on the side nearer the engine than a throttle chamber 18 which increases and decreases the suction amount of the engine. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an apparatus for improving the quality of intake sound generated from an intake system of, for example, an automobile.

2. Description of the Related Art Conventionally, an intake sound adjusting device has been devised that can obtain an intake sound with a sense of force by introducing intake sound generated in an intake path to an engine into a vehicle compartment when the vehicle is running.
As such an intake sound adjusting device, for example, as described in Patent Document 1, there is a configuration including a communication pipe, an elastic body, and an additional pipe.
The communication pipe is attached to a position farther from the engine than the throttle chamber that increases or decreases the intake air amount of the engine on the outer peripheral surface of the intake duct, and communicates with the intake duct.

The elastic body closes the communication pipe and vibrates according to the intake pulsation in the intake duct.
One open end of the additional pipe is connected to the communication pipe, and the other open end is opened to the outside air.
In such an intake sound adjusting device, the elastic body vibrates according to the intake pulsation generated in the gas in the intake duct. For this reason, the intake sound is radiated into the outside air from the other opening end of the additional pipe, and it is possible to introduce a powerful intake sound into the vehicle interior.
Japanese Patent Laying-Open No. 2005-139882 (FIGS. 1, 12, and 13)

However, in the intake sound adjusting device described in Patent Document 1, the intake sound is increased according to the intake pulsation generated in the gas in the intake duct regardless of the amount of depression of the accelerator pedal by the driver. .
Therefore, there is a possibility that a problem that the intake sound is increased even when it is desired to ensure quietness such as when the driver depresses the accelerator pedal and when the vehicle is slowly accelerating or idling.
The present invention has been made paying attention to the above-mentioned problems, and an intake sound adjustment device capable of reducing the effect of increasing the intake sound when quietness is desired, such as during slow acceleration or idling. The issue is to provide.

In order to solve the above-mentioned problems, the present invention is an intake sound adjusting device in which one end communicates with an intake passage to an engine and the other end communicates with outside air with an elastic body.
It is an object of the present invention to provide an intake sound adjusting device characterized in that the flow passage area of the communication pipe is changed by a change in intake negative pressure generated in the intake passage.

  According to the present invention, it is possible to reduce the effect of increasing the intake sound when it is desired to ensure quietness during slow acceleration or idling.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
(Constitution)
FIG. 1 is a diagram illustrating a configuration concept of an intake sound adjusting device 1 of the present embodiment.
As shown in FIG. 1, the intake sound adjustment device 1 of this embodiment is attached to an intake duct 2 and includes a communication pipe 4, an elastic body 6, and a flow path area changing means 8.

First, the structure of the portion related to the intake duct 2 and the intake duct 2 will be described.
The intake duct 2 forms an intake passage from the outside air to the engine 10, and includes a dust side intake duct 12 and a clean side intake duct 14.
One open end of the dust side intake duct 12 is connected to an air cleaner 16. The other open end of the dust side intake duct 12 is open to the outside air.

The air cleaner 16 has a filter part such as an oil filter, for example, and cleans the gas flowing in from the other opening end of the dust side intake duct 12 by passing the filter part.
The clean side intake duct 14 includes a throttle chamber 18.
One open end of the clean side intake duct 14 is connected to an air cleaner 16. The other open end of the clean side intake duct 14 is connected to each cylinder (not shown) of the engine 10 via a surge tank 20 and each intake manifold 22 described later.

The throttle chamber 18 is attached between the air cleaner 16 and the surge tank 20 and is connected to an accelerator pedal (not shown). Further, the throttle chamber 18 changes its opening according to the amount of depression of the accelerator pedal by the driver, and increases or decreases the amount of ventilation from the air cleaner 16 to the surge tank 20.
Specifically, when the driver decreases the amount of depression of the accelerator pedal (hereinafter referred to as “slow acceleration”), the opening degree of the throttle chamber 18 decreases, and the air flow from the air cleaner 16 to the surge tank 20 Decrease. Then, the intake negative pressure generated in the gas in the clean side intake duct 14 decreases.

When the opening degree of the throttle chamber 18 decreases, the intake negative pressure generated in the clean side intake duct 14 in the portion closer to the engine 10 than the throttle chamber 18 (hereinafter referred to as “engine side intake negative”). Pressure ”).
When the opening degree of the throttle chamber 18 is “0”, the clean side intake duct 14 is separated into a part closer to the engine 10 than the throttle chamber 18 and a part farther away from the engine 10 than the throttle chamber 18. . That is, when the throttle chamber 18 is closed, the engine-side intake negative pressure has a maximum value. FIG. 2 shows a state where the throttle chamber 18 is closed.

  Note that the above-described state where the opening degree of the throttle chamber 18 is “0”, that is, the state where the throttle chamber 18 is closed includes the idling of the engine 10 when the driver does not step on the accelerator pedal. In addition, for example, it includes a transition from a traveling state in which the driver depresses the accelerator pedal to a stop state in which the operation of depressing the accelerator pedal is stopped.

  On the other hand, when the amount of depression of the accelerator pedal is increased (hereinafter referred to as “at the time of rapid acceleration”), the opening degree of the throttle chamber 18 is increased and the amount of ventilation from the air cleaner 16 to the surge tank 20 is increased. Then, the intake negative pressure generated in the gas in the clean side intake duct 14 increases. FIG. 3 shows a state where the opening degree of the throttle chamber 18 is maximum.

Therefore, if the opening degree of the throttle chamber 18 is increased from the state in which the throttle chamber 18 is closed, the engine-side intake negative pressure decreases.
In the intake process, the engine 10 flows gas from the other opening end of the dust side intake duct 12 into the clean side intake duct 14 through each surge cylinder 20 and each intake manifold 22 to each cylinder. Intake into (not shown).

Further, the engine 10 forms a pressure source that generates an intake pulsation in the gas existing in the clean side intake duct 14 in accordance with the intake operation, and the intake pulsation constitutes an intake sound.
Here, the intake air pulsation generated in association with the intake operation of the engine 10 is a pressure fluctuation generated in the gas existing in the clean side intake duct 14, and this pressure fluctuation is composed of pressure fluctuations of a plurality of frequencies. ing. That is, the intake pulsation generated in association with the intake operation of the engine 10 is composed of intake pulsations having a plurality of frequencies.

Next, the structure of the communication pipe 4, the elastic body 6, and the flow path area changing means 8 will be described.
The communication pipe 4 has a cylindrical shape, and one end thereof communicates with the clean side intake duct 14 in a portion of the outer peripheral surface of the clean side intake duct 14 that is farther from the engine 10 than the throttle chamber 18. It is attached. That is, one end of the communication pipe 4 communicates with the intake passage of the engine 10. The other end of the communication tube 4 communicates with the outside air.
The elastic body 6 is formed in a disk shape using an elastic resin material such as rubber, and is attached to the inner peripheral surface of the communication pipe 4 to close the communication pipe 4. The elastic body 6 vibrates in the out-of-plane direction by being elastically deformed according to the intake pulsation generated in the clean side intake duct 14.

Hereinafter, the detailed configuration of the flow path area changing means 8 will be described with reference to FIGS.
2 and 3 are diagrams showing the detailed configuration of the flow path area changing means 8, FIG. 2 is a view showing the state of the flow path area changing means 8 during slow acceleration and idling, and FIG. It is a figure which shows the state of the flow-path area change means 8 at the time of rapid acceleration.
As shown in FIGS. 2 and 3, the flow path area changing means 8 includes a flow path area changing portion 24 and a displacement means 26.

The flow path area changing portion 24 is formed by an elliptical plate-like member formed in a shape corresponding to the cross-sectional shape of the communication pipe 4, and in the communication pipe 4, the cleaner side intake duct than the elastic body 6. 14 side.
Further, the flow path area changing portion 24 is supported so as to be displaceable by rotating around the axis intersecting the length direction of the communication pipe 4 with respect to the communication pipe 4. In FIGS. 2 and 3, the rotation center of the flow path area changing portion 24 with respect to the communication pipe 4 is indicated by a reference sign “P”.

When the flow path area changing portion 24 is rotated and displaced in the communication pipe 4, the flow area of the gas moving between the clean side intake duct 14 and the elastic body 6 (hereinafter simply referred to as “flow path area”). Change). In FIG. 2, the direction of displacement of the flow path area changing portion 24 is represented by a semicircular arrow.
Specifically, when the flow path area changing section 24 is rotated and displaced in the communication pipe 4 and the longitudinal direction of the flow path area changing section 24 is inclined with respect to the length direction of the communication pipe 4, the inclination angle is increased. As it increases, the opening degree of the communication pipe 4 decreases and the flow path area decreases from the maximum value.

When the inclination angle of the longitudinal direction of the flow channel area changing portion 24 with respect to the length direction of the communication tube 4 increases, and the flow channel area changing portion 24 comes into contact with the inner peripheral surface of the communication tube 4 as shown in FIG. The opening degree of the communication pipe 4 becomes the minimum value, and the space between the clean side intake duct 14 and the elastic body 6 is closed. In this state, the flow path area becomes the minimum value.
Further, the flow path area changing portion 24 is rotated and displaced in the communication pipe 4, and the flow path area changes from the state in which the longitudinal direction of the flow path area change section 24 is inclined with respect to the length direction of the communication pipe 4. As the longitudinal direction of the change portion 24 becomes parallel to the length direction of the communication pipe 4, the opening degree of the communication pipe 4 increases. For this reason, the channel area approaches the maximum value.

As shown in FIG. 3, when the longitudinal direction of the flow path area changing portion 24 is parallel to the length direction of the communication pipe 4, the opening degree of the communication pipe 4 becomes the maximum value, and the flow path area becomes the maximum value. Become.
The displacement means 26 includes a negative pressure introducing chamber 28, a closing plate 30, and a closing plate urging means 32.
The negative pressure introduction chamber 28 includes an introduction pipe portion 34 and a cylinder portion 36.
The introduction pipe part 34 is formed in a cylindrical shape by a steel pipe, for example.
One end of the introduction pipe portion 34 is attached to a position closer to the engine 10 than the throttle chamber 18 on the outer peripheral surface of the clean side intake duct 14 and communicates with the clean side intake duct 14. The other end of the introduction tube portion 34 communicates with the cylinder portion 36.

The cylinder portion 36 is formed of a steel pipe like the introduction pipe portion 34, has a cylindrical shape larger in diameter than the introduction pipe portion 34, and the axis is parallel to the length direction of the clean side intake duct 14. Arranged in the state.
One end of the cylinder portion 36 opens to the communication tube 4 side. The other end of the cylinder portion 36 is closed to form a bottom surface. An opening is formed in the outer peripheral surface of the cylinder portion 36, and this opening communicates with the other end of the introduction tube portion 34, and the introduction tube portion 34 and the cylinder portion 36 communicate with each other.

The closing plate 30 is a plate-like member formed in a circular shape according to the cross-sectional shape of the cylinder portion 36, and is disposed in the cylinder portion 36 so as to be slidable with respect to the inner peripheral surface of the cylinder portion 36. The pressure introducing chamber 28 is closed.
Further, the closing plate 30 is connected to the flow path area changing portion 24 via a connecting member 38.
The connecting member 38 includes a flow channel area changing portion side connecting member 38 a attached to the flow passage area changing portion 24 and a closing plate side connecting member 38 b attached to the closing plate 30.

The flow path area changing portion side connecting member 38 a is formed in a rod shape and attached in parallel to the flow path area changing portion 24, and one end of the flow passage area changing portion 24 is connected to the communication pipe 4. It is supported coaxially with the rotation center P, and the other end is connected to the closing plate side connecting member 38b.
The closing plate side connecting member 38b is formed in a rod shape, and one end thereof is connected to the flow path area changing portion side connecting member 38a so as to be rotatable around an axis intersecting the length direction of the communication pipe 4. The other end is attached to the surface of the closing plate 30 on the side of the communication pipe 4.

The closing plate urging means 32 is formed by, for example, a coil spring. One end of the closing plate urging means 32 is attached to a surface opposite to the surface of the closing plate 30 on the side of the communication tube 4, and the other end is connected to the cylinder portion 36. Is attached to the bottom surface of the cylinder portion 36 and can be expanded and contracted along the axial direction of the cylinder portion 36.
The spring constant of the closing plate urging means 32 is set to a value that allows the closing plate 30 to move to the bottom surface side of the cylinder portion 36 in a state where the engine-side intake negative pressure is equal to or higher than a predetermined pressure. In FIG. 2, the flow of engine-side intake negative pressure is represented by a white arrow.

  When the closing plate 30 moves to the bottom surface side of the cylinder portion 36, the flow path area changing portion 24 rotates and displaces so that the flow path area decreases from the maximum value. In this case, as shown in FIG. 2, the spring constant of the closing plate urging means 32 is such that the flow passage area changing portion 24 rotates and displaces in the communication pipe 4, and the flow passage area changing portion 24 is changed to that of the communication pipe 4. Until the contact with the inner peripheral surface, the closing plate 30 is allowed to move to the bottom surface side of the cylinder portion 36. That is, the spring constant of the closing plate urging means 32 is applied to the bottom surface side of the cylinder portion 36 of the closing plate 30 until the flow path area changing portion 24 closes the space between the clean side intake duct 14 and the elastic body 6. It is a value that allows movement.

The spring constant of the closing plate urging means 32 is such that the closing plate 30 is pressed and urged toward the communication pipe 4 as shown in FIG. 3 in a state where the engine-side intake negative pressure is less than a predetermined pressure. The value to be moved is set.
When the blocking plate 30 moves to the communication pipe 4 side, the flow path area changing unit 24 is rotated and displaced so that the flow path area becomes the maximum value.
Here, the “predetermined pressure” means that the driver does not depress the accelerator pedal and that the driver is not accelerating slowly or when the driver is idling when the driver does not depress the accelerator pedal. This is the engine-side intake negative pressure in a situation inappropriate to increase sound.
Therefore, the flow passage area changing means 8 has a function of displacing the flow passage area changing portion 24 by a change in the engine-side intake negative pressure.

The displacement means 26 has a maximum flow path area when the engine-side intake negative pressure is less than a predetermined pressure, and has a maximum flow path area when the engine-side intake negative pressure is equal to or greater than the predetermined pressure. It has a function of displacing the flow path area changing portion 24 so as to be smaller than the value.
As described above, the displacement means 26 displaces the flow path area changing portion 24 in a direction in which the opening degree of the communication pipe 4 decreases in a state where the engine-side intake negative pressure is equal to or higher than a predetermined pressure, and the engine-side intake negative pressure Is provided with opening degree changing means for displacing the flow path area changing unit 24 in a direction in which the opening degree of the communication pipe 4 increases in a state where the pressure is less than a predetermined pressure. The opening changing means includes a closing plate 30 and a closing plate urging means 32.

As shown in FIGS. 2 and 3, the communication pipe 4 is composed of a first series pipe construction part 4 a and a second communication pipe construction part 4 b.
The first continuous pipe constituting portion 4a is disposed closer to the clean side intake duct 14 than the second communicating pipe constituting portion 4b, and is communicated with the clean side intake duct 14. In other words, the first series pipe configuration part 4 a communicates with the intake passage of the engine 10.
The second communication pipe component 4b is arranged at a position farther from the clean side intake duct 14 than the first series pipe configuration part 4a, that is, on the outside air side from the first series pipe configuration part 4a.
The elastic body 6 is sandwiched between the first continuous pipe constituting portion 4a and the second communicating pipe constituting portion 4b and attached to the inner peripheral surface of the communicating pipe 4, and the communicating pipe 4 is specifically closed. Closes the first continuous pipe component 4a.

Here, the first continuous pipe constituting part 4a and the second communicating pipe constituting part 4b include a first resonance frequency constituted by the first continuous pipe constituting part 4a and the elastic body 6, and a second communicating pipe constituting part 4b. The second resonance frequency formed from the elastic body 6 is formed in a shape that resonates.
The shape in which the first resonance frequency and the second resonance frequency resonate is, for example, that the pipe length of the first continuous pipe constituent portion 4a and the pipe length of the second communication pipe constituent portion 4b are the same length. In addition, the cross-sectional area of the first continuous pipe component 4a and the cross-sectional area of the second communication pipe component 4b are both the same cross-sectional area.

(Operation)
Next, the operation of the intake sound adjusting device 1 will be described.
When the engine 10 is driven, the intake pulsation generated by the intake operation of the engine 10 is propagated to the gas present in the clean side intake duct 14 via each intake manifold 22 and the surge tank 20 (FIG. 1). reference).
Here, during idling when the driver does not depress the accelerator pedal, or during slow acceleration where the amount of depression of the accelerator pedal is small and the driver's acceleration intention is weak, the opening of the throttle chamber 18 is small. The pressure is equal to or higher than a predetermined pressure (see FIG. 2).

When the engine-side intake negative pressure becomes equal to or higher than a predetermined pressure, the inside of the negative pressure introduction chamber 28 becomes negative pressure, the closing plate urging means 32 contracts, and the closing plate 30 slides with respect to the inner peripheral surface of the cylinder portion 36. It moves and moves to the bottom side of the cylinder part 36 (see FIG. 2).
When the closing plate 30 moves to the bottom surface side of the cylinder portion 36, the closing plate side connecting member 38 b moves to the bottom surface side of the cylinder portion 36. Then, the flow path area changing portion side connecting member 38a rotates around the axis intersecting the length direction of the communicating tube 4 with respect to the blocking plate side connecting member 38b toward the outer peripheral side of the communicating tube 4 (FIG. 2). reference).

When the flow path area changing portion side connecting member 38a rotates around the axis intersecting the length direction of the communication pipe 4 with respect to the blocking plate side connecting member 38b toward the outer peripheral side of the communication pipe 4, the flow path area changes. The part 24 rotates and displaces in the communication pipe 4, and the flow path area decreases from the maximum value (see FIG. 2).
At this time, when the flow path area changing portion 24 comes into contact with the inner peripheral surface of the communication pipe 4, the space between the clean side intake duct 14 and the elastic body 6 is closed, and the flow path area becomes the minimum value (see FIG. 2). ).

For this reason, the propagation of the intake air pulsation generated in the intake operation of the engine 10 and propagated to the gas present in the clean side intake duct 14 to the elastic body 6 is suppressed, and the vibration of the elastic body 6 is suppressed. (See FIG. 2).
Therefore, at the time of idling and slow acceleration, the flow passage area decreases from the maximum value, and the propagation of the intake pulsation propagated to the gas existing in the clean side intake duct 14 to the elastic body 6 is suppressed. 6 is suppressed, it is possible to reduce the effect of increasing the intake sound (see FIG. 2).

Further, during idling and slow acceleration, the space between the clean-side intake duct 14 and the elastic body 6 is closed, and the flow passage area becomes the minimum value. Therefore, the effect of increasing the intake noise can be greatly reduced. The intake noise introduced into the passenger compartment is small (see FIG. 2).
On the other hand, the opening degree of the throttle chamber 18 is large at the time of rapid acceleration where the amount of depression of the accelerator pedal by the driver is large and the driver is willing to accelerate. For this reason, the intake negative pressure generated in the gas in the clean side intake duct 14 in the intake process of the engine becomes higher than that during slow acceleration, and the engine intake negative pressure becomes less than a predetermined pressure (see FIG. 3). ).

When the engine-side intake negative pressure becomes less than a predetermined pressure, the inside of the negative pressure introduction chamber 28 approaches the positive pressure from the negative pressure, the closing plate urging means 32 extends, and the closing plate 30 is connected to the inner peripheral surface of the cylinder portion 36. To move to the communication pipe 4 side (see FIG. 3).
When the blocking plate 30 moves to the communication tube 4 side, the blocking plate side connecting member 38b moves to the communication tube 4 side, and the flow path area changing portion side connecting member 38a moves toward the center of the communication tube 4 so that the blocking plate side It rotates about the axis | shaft which cross | intersects the length direction of the communicating pipe 4 with respect to the connection member 38b (refer FIG. 3).

When the flow path area changing portion side connecting member 38a rotates around the axis intersecting the length direction of the communicating tube 4 with respect to the blocking plate side connecting member 38b toward the center of the communicating tube 4, the flow passage area changing portion. 24 rotates and displaces in the communication pipe 4 and leaves the inner peripheral surface of the communication pipe 4. The clean side air intake duct 14 and the elastic body 6 communicate with each other (see FIG. 3).
At this time, when the clean side intake duct 14 and the elastic body 6 communicate with each other and the longitudinal direction of the flow path area changing portion 24 is parallel to the length direction of the communication pipe 4, the flow path area becomes the maximum value. (See FIG. 3).

For this reason, the intake pulsation, which is generated along with the intake operation of the engine 10 and propagates to the gas existing in the clean side intake duct 14, is propagated to the elastic body 6, and the elastic body 6 vibrates in the out-of-plane direction. Then, the increased intake sound is radiated into the outside air from the other opening end of the communication pipe 4 (see FIG. 1).
Therefore, at the time of rapid acceleration, the flow path area becomes the maximum value, and the elastic body 6 vibrates in the out-of-plane direction due to the intake pulsation propagated to the elastic body 6, so that the intake sound that contributes to the acceleration feeling is increased. (See FIG. 3).

(Effects of the first embodiment)
(1) In the intake sound adjusting device of the present embodiment, the flow area of the gas moving between the intake duct and the elastic body can be changed by the change in the engine-side intake negative pressure by the flow area changing means. It becomes possible.
For this reason, in a state where the engine-side intake negative pressure is equal to or higher than a predetermined pressure, that is, at the time of slow acceleration and idling, the space between the clean-side intake duct and the elastic body is blocked, and the flow passage area is more than the maximum value. Can also be reduced.
Further, in a state where the engine-side intake negative pressure is less than a predetermined pressure, that is, during rapid acceleration, the clean-side intake duct and the elastic body may be communicated to maximize the flow path area. It becomes possible.

Therefore, at the time of slow acceleration and idling when it is desired to ensure quietness, in order to suppress the vibration of the elastic body by suppressing the propagation of the intake pulsation propagated to the gas existing in the clean side air intake duct to the elastic body, It is possible to reduce the effect of increasing the intake sound.
On the other hand, at the time of sudden acceleration where the driver's willingness to accelerate is strong, the elastic body vibrates in the out-of-plane direction due to the intake pulsation propagated to the elastic body. Radiated into the open air.
As a result, it is possible to ensure both quietness during slow acceleration and idling, and to increase intake sound during sudden acceleration, so sporty sound does not cause discomfort to vehicle occupants. Can be produced.

(2) Further, in the intake sound adjusting device of the present embodiment, when the engine-side intake negative pressure becomes equal to or higher than a predetermined pressure, the flow passage area changing portion comes into contact with the inner peripheral surface of the communication pipe, and the clean-side intake duct And the elastic body is closed.
For this reason, in a state where the engine-side intake negative pressure is equal to or higher than a predetermined pressure, the propagation of the intake pulsation that has propagated to the gas existing in the clean-side intake duct to the elastic body is suppressed, and the vibration of the elastic body Therefore, the effect of increasing the intake sound can be greatly reduced.
As a result, when the engine-side intake negative pressure is equal to or higher than the predetermined pressure, during slow acceleration and idling, it is possible to greatly reduce the effect of increasing the intake noise, and the intake noise introduced into the passenger compartment Will be slight.

(3) Further, in the intake sound adjusting device of the present embodiment, the flow channel area changing means includes a flow channel area changing unit that changes the flow channel area of the communication pipe, and a flow channel by changing the intake negative pressure in the intake duct. Displacement means for displacing the area changing portion.
As a result, the flow path area changing portion can be displaced by a change in the intake negative pressure in the intake duct without requiring an actuator or the like.

(4) Further, in the intake sound adjusting device of the present embodiment, the opening of the communication pipe decreases when the displacement means is in a negative pressure introduction chamber communicating with the intake passage and the intake negative pressure is equal to or higher than a predetermined pressure. Opening degree changing means for displacing the flow path area changing part in a direction in which the opening degree of the communication pipe is increased in a state where the flow path area changing part is displaced in a direction in which the intake negative pressure is less than a predetermined pressure. Prepare.
As a result, the opening degree of the communication pipe can be changed by displacing the flow path area changing portion by the change of the intake negative pressure in the intake duct.

(5) Further, in the intake sound adjusting device of the present embodiment, the opening degree changing means closes the negative pressure introduction chamber and connects to the flow passage area changing portion, and the intake negative pressure is less than a predetermined pressure. A blocking plate urging means for pressing and urging the blocking plate so that the flow path area changing portion is displaced in a direction in which the opening of the communication pipe increases in a certain state.
For this reason, it is possible to set the spring constant of the closing plate urging means according to the slow acceleration and idling when it is desired to suppress the effect of increasing the intake sound and during the rapid acceleration when it is desired to increase the intake sound.
As a result, depending on the preference of the owner of the vehicle, for example, different settings may be used for each vehicle, such as slow acceleration at which to increase the intake noise and sudden acceleration at which to increase the intake noise. It becomes possible to cope with.

(6) Moreover, in the intake sound adjusting device of the present embodiment, the flow path area changing portion is formed by an elliptical plate-like member formed in a shape corresponding to the cross-sectional shape of the communication pipe. Further, the flow path area changing portion is supported so as to be rotatable about an axis intersecting the length direction of the communication pipe with respect to the communication pipe.
As a result, the flow channel area of the communication pipe can be changed by rotating the flow channel area changing portion around the axis intersecting the length direction of the communication pipe in the communication pipe.

(7) Further, in the intake sound adjusting device of the present embodiment, the communication pipe is connected to the intake passage and the second communication pipe is disposed closer to the outside air than the first communication pipe component. It consists of a tube component.
As a result, the elastic body can be easily replaced when the elastic body needs to be replaced, such as when the elastic body is damaged. Moreover, it becomes easy to differ the structure of a 1st continuous pipe structure part and a 2nd communication pipe structure part.

(Application example)
(1) In the intake sound adjusting device 1 of the present embodiment, the communication pipe 4 is attached to a portion of the outer peripheral surface of the clean side intake duct 14 that is farther from the engine 10 than the throttle chamber 18. However, the present invention is not limited to this. In other words, the communication pipe 4 may be attached to a portion of the outer peripheral surface of the clean side intake duct 14 that is closer to the engine 10 than the throttle chamber 18.
(2) Further, in the intake sound adjustment device 1 of the present embodiment, the negative pressure introduction chamber 28 is constituted by the introduction pipe portion 34 and the cylinder portion 36, but is not limited thereto. That is, the negative pressure introduction chamber 28 may be constituted by, for example, one cylindrical member. In this case, the closing plate urging means 32 is fixed inside the negative pressure introducing chamber 28 by, for example, welding or adhesion.

(3) Further, in the intake sound adjusting device 1 of the present embodiment, the closing plate 30 is connected to the flow path area changing portion 24 via the connecting member 38, but is not limited thereto. That is, for example, when a slit is formed on the outer peripheral surface of the communication pipe 4 and the flow path area changing portion 24 is arranged inside the communication pipe 4 through the slit from the outside of the communication pipe 4, the blocking plate 30 and the flow path area changing portion 24 may be directly connected without using a connecting member.

(4) Further, in the intake sound adjusting device 1 of the present embodiment, the elastic body 6 is sandwiched between the first series of pipe constituent parts 4a and the second communication pipe constituent part 4b. Not what you want. That is, the communication pipe 4 may be constituted by a single cylindrical member, and the elastic body 6 may be attached to the inner peripheral surface thereof by adhesion or the like to close the communication pipe 4. In this case, for example, an additional pipe connected to the communication pipe 4 with the elastic body 6 interposed therebetween may be provided. Furthermore, the shape of the communication tube 4 and the additional tube may be a shape in which the first resonance frequency composed of the communication tube 4 and the elastic body 6 resonates with the second resonance frequency composed of the additional tube and the elastic body 6. .

(5) Further, in the intake sound control device 1 of the present embodiment, the engine 10 is used as the pressure source for generating pressure fluctuations in the gas existing in the intake duct 2, but the pressure fluctuations in the gas existing in the intake duct 2. The pressure source for generating the pressure is not limited to this, and may be a pump, for example. In short, the intake sound adjustment device 1 of the present embodiment includes a vent pipe that communicates with a pressure source that generates a pressure fluctuation in the gas, and is applied to the one in which the pressure fluctuation occurs in the gas existing in the vent pipe. Is possible.

(6) In addition, in the intake sound adjustment device 1 of the present embodiment, the introduction pipe portion 34 is formed of a steel pipe, but the configuration of the introduction pipe portion 34 is not limited to this, and the introduction pipe portion 34 is For example, you may form by members having flexibility, such as a hose and a tube. In this case, it is preferable to have a configuration including a holding member capable of holding the position of the cylinder portion 36 with respect to the communication pipe 4.

(7) Further, in the intake sound adjusting device 1 of the present embodiment, the first continuous pipe constituting portion 4a and the second communicating pipe constituting portion 4b are formed to have the same inner diameter, but the present invention is limited to this. is not. That is, for example, the cross-sectional area of the second communication pipe component 4b may be larger than the cross-sectional area of the first series of pipe components 4a.
(8) Further, in the intake sound adjusting device 1 of the present embodiment, the first continuous pipe constituting portion 4a and the second communicating pipe constituting portion 4b are formed to have the same length, but the present invention is limited to this. It is not a thing. That is, the length of the first continuous pipe constituting portion 4a may be different from the length of the second communicating pipe constituting portion 4b.

(Second embodiment)
(Constitution)
Next, a second embodiment of the present invention will be described.
4 and 5 are diagrams showing the configuration of the intake sound adjusting device 1 of the present embodiment. FIG. 4 is a diagram showing the state of the flow path area changing means 8 during slow acceleration and idling. FIG. FIG. 6 is a diagram showing a state of the flow path area changing means 8 during rapid acceleration.
As shown in FIGS. 4 and 5, the configuration of the intake sound adjusting device 1 of the present embodiment is the same as that of the first embodiment described above except for the configuration of the flow path area changing means 8. Since the configuration other than the flow path area changing means 8 is the same as that of the first embodiment described above, the description thereof is omitted.

The channel area changing unit 8 includes a channel area changing unit 24 and a displacement unit 26.
The flow path area changing portion 24 is formed by an elliptical plate-like member formed in a shape corresponding to the cross-sectional shape of the communication pipe 4, and in the communication pipe 4, the intake air on the clean side than the elastic body 6. It arrange | positions at the duct 14 side.
Further, the flow path area changing portion 24 is rotated and displaced about an axis intersecting the length direction of the communication pipe 4 with respect to the communication pipe 4 on the inner peripheral surface of the communication pipe 4 on the negative pressure introduction chamber 28 side. I support it as possible. In FIGS. 4 and 5, the rotation center of the flow path area changing portion 24 with respect to the communication pipe 4 is indicated by a reference sign “P”.

When the flow path area changing portion 24 rotates and displaces in the communication pipe 4, the flow path area changes.
Specifically, when the flow path area changing section 24 is rotated and displaced in the communication pipe 4 and the longitudinal direction of the flow path area changing section 24 is inclined with respect to the length direction of the communication pipe 4, the inclination angle increases. As the operation proceeds, the opening degree of the communication pipe 4 decreases and the flow path area decreases from the maximum value. In FIG. 4, as in FIG. 2, the displacement direction of the flow path area changing portion 24 is represented by a semicircular arrow.

  The inclination angle of the longitudinal direction of the flow passage area changing portion 24 with respect to the length direction of the communication tube 4 is increased, and the end of the flow passage area changing portion 24 on the elastic body 6 side is connected to the communication tube, as shown in FIG. If it contacts with the 4 inner peripheral surface, the opening degree of the communicating pipe 4 will become the minimum value. In this state, the space between the clean side intake duct 14 and the elastic body 6 is closed, and the flow path area becomes the minimum value. 4 shows a state in which the throttle chamber 18 is closed as in FIG.

Further, when the flow path area changing section 24 is rotated and displaced in the communication pipe 4, the flow path area changes from the state in which the longitudinal direction of the flow path area changing section 24 is inclined with respect to the length direction of the communication pipe 4. As the longitudinal direction of the change portion 24 becomes parallel to the length direction of the communication pipe 4, the opening degree of the communication pipe 4 increases. Therefore, the channel area approaches the maximum value.
Then, as shown in FIG. 5, the longitudinal direction of the flow path area changing portion 24 is parallel to the length direction of the communication pipe 4, and the surface of the flow passage area changing portion 24 on the negative pressure introduction chamber 28 side is in communication. It contacts the inner peripheral surface of the tube 4 on the negative pressure introduction chamber 28 side. In this state, the opening degree of the communication pipe 4 is the maximum value, and the flow path area is the maximum value. FIG. 5 shows a state where the opening degree of the throttle chamber 18 is maximum, as in FIG.

The displacement means 26 includes a negative pressure introducing chamber 28 and an elastic film portion 44.
The negative pressure introduction chamber 28 includes an introduction pipe portion 34 and a cylinder portion 36.
The introduction pipe portion 34 is formed of, for example, a steel pipe and has a cylindrical shape.
One end of the introduction pipe portion 34 is attached to a position closer to the engine 10 than the throttle chamber 18 on the outer peripheral surface of the clean side intake duct 14 and communicates with the clean side intake duct 14. The other end of the introduction tube portion 34 communicates with the cylinder portion 36.

The cylinder part 36 includes a first cylinder part constituting part 40 on the communication pipe 4 side and a second cylinder part constituting part 42 farther from the communicating pipe 4 than the first cylinder part constituting part 40.
Both the first cylinder part constituting part 40 and the second cylinder part constituting part 42 are formed of a steel pipe and have a cylindrical shape having a diameter larger than that of the introduction pipe part 34, and the shaft is the length of the clean side intake duct 14. They are arranged in parallel with the vertical direction.

One end portion of the first cylinder portion constituting portion 40 is attached to a position closer to the clean side air intake duct 14 than the elastic body 6 on the outer peripheral surface of the communication tube 4 and communicates with the communication tube 4. The other end portion of the first cylinder portion constituting portion 40 communicates with one end portion of the second cylinder portion constituting portion 42.
The other end portion of the cylinder portion 36 of the second cylinder portion constituting portion 42 communicates with the other end portion of the introduction pipe portion 34. That is, the introduction pipe portion 34 and the cylinder portion 36 are in communication.

The elastic film portion 44 is a plate-like member formed in a circular shape by a resin material having elasticity, such as rubber, and has elasticity that elastically deforms in the out-of-plane direction due to a change in engine-side intake negative pressure. In FIG. 4, as in FIG. 2, the flow of the engine-side intake negative pressure is represented by a white arrow.
In addition, the outer peripheral portion of the elastic membrane portion 44 is sandwiched between the first cylinder portion constituting portion 40 and the second cylinder portion constituting portion 42 and attached to the inner peripheral surface of the cylinder portion 36, so that negative pressure is introduced. The chamber 28 is closed, specifically, the cylinder portion 36 is closed.

The elastic film portion 44 is connected to the flow path area changing portion 24 via a connecting member 38 formed in a rod shape.
One end of the connecting member 38 is attached at a right angle to the flow path area changing portion 24, and the other end is attached to the surface of the elastic membrane portion 44 on the side of the communication tube 4.
The elasticity of the elastic membrane portion 44 is set to a value that elastically deforms toward the second cylinder portion constituting portion 42 in a state where the engine-side intake negative pressure is equal to or higher than a predetermined pressure.

  When the elastic film part 44 is elastically deformed toward the second cylinder part constituting part 42 side, the flow path area changing part 24 is rotated and displaced so that the flow path area is reduced from the maximum value. In this case, as shown in FIG. 4, the elasticity of the elastic membrane portion 44 is such that the flow path area changing portion 24 rotates and displaces in the communication pipe 4, and the flow path area changing section 24 The value is in contact with the peripheral surface. That is, the elasticity of the elastic film portion 44 is a value that elastically deforms toward the second cylinder portion constituting portion 42 until the space between the clean side intake duct 14 and the elastic body 6 is closed.

In addition, the elasticity of the elastic film portion 44 is set to a value that elastically deforms toward the communication pipe 4 in a state where the engine-side intake negative pressure is less than a predetermined pressure. In this case, as shown in FIG. 5, the elasticity of the elastic film portion 44 is such that the flow path area changing portion 24 rotates in the communication pipe 4 and the flow passage area changing portion 24 is on the negative pressure introduction chamber 28 side. The surface is set to a value in contact with the inner peripheral surface of the communication pipe 4 on the negative pressure introduction chamber 28 side. That is, the elasticity of the elastic membrane portion 44 is a value that elastically deforms toward the communication pipe 4 until the flow path area reaches the maximum value.
When the elastic membrane portion 44 is elastically deformed toward the communication tube 4, as shown in FIG. 5, the flow passage area changing portion 24 is rotated and displaced so that the flow passage area becomes the maximum value.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the intake sound adjustment device 1 of the present embodiment will be described. In the following description, since the configuration other than the flow path area changing means 8 is the same as that of the first embodiment described above, the operation of different parts will be mainly described.
When the engine 10 is driven, the intake pulsation generated by the intake operation of the engine 10 is propagated to the gas present in the clean side intake duct 14 via each intake manifold 22 and the surge tank 20 (FIG. 1). reference).

Here, at the time of idling or slow acceleration, since the opening degree of the throttle chamber 18 is small, the engine-side intake negative pressure becomes equal to or higher than a predetermined pressure, and the inside of the negative pressure introduction chamber 28 becomes negative pressure. For this reason, the elastic film part 44 is elastically deformed toward the second cylinder part constituting part 42 side (see FIG. 4).
When the elastic membrane part 44 is elastically deformed toward the second cylinder part constituting part 42 side, the flow path area changing part 24 is around the axis intersecting the length direction of the communication pipe 4 so that the flow path area is reduced below the maximum value. (See FIG. 4).

When the flow path area changing portion 24 rotates around the axis intersecting the length direction of the communication pipe 4, the flow path area changing section 24 rotates and displaces in the communication pipe 4, and the flow path area is reduced from the maximum value. (See FIG. 4).
At this time, when the end of the flow passage area changing portion 24 on the elastic body 6 side comes into contact with the inner peripheral surface of the communication pipe 4, the space between the clean side intake duct 14 and the elastic body 6 is closed, and the flow passage area is increased. The minimum value is obtained (see FIG. 4).

Therefore, the vibration of the elastic body 6 is suppressed by suppressing the propagation of the intake air pulsation generated in the intake operation of the engine 10 to the gas existing in the clean side intake duct 14 to the elastic body 6. (See FIG. 4).
Therefore, at the time of idling and slow acceleration, the flow passage area decreases from the maximum value, and the propagation of the intake pulsation propagated to the gas existing in the clean side intake duct 14 to the elastic body 6 is suppressed. 6 is suppressed, it is possible to reduce the effect of increasing the intake sound (see FIG. 4).

Further, during idling and slow acceleration, the space between the clean-side intake duct 14 and the elastic body 6 is closed, and the flow passage area becomes the minimum value. Therefore, the effect of increasing the intake noise can be greatly reduced. It becomes possible, and the intake sound introduced into the vehicle interior is slight (see FIG. 4).
On the other hand, at the time of rapid acceleration, since the opening degree of the throttle chamber 18 is large, the engine-side intake negative pressure becomes less than a predetermined pressure, the inside of the negative pressure introduction chamber 28 approaches from negative pressure to positive pressure, and the elastic film portion 44. However, it is elastically deformed to the communication tube 4 side (see FIG. 5).
When the elastic membrane portion 44 is elastically deformed toward the communication tube 4, the flow path area changing portion 24 rotates around an axis that intersects the length direction of the communication tube 4, and the clean side intake duct 14, the elastic body 6, Communicate with each other (see FIG. 5).

The longitudinal direction of the flow passage area changing portion 24 is parallel to the length direction of the communication pipe 4, and the surface of the flow passage area changing portion 24 on the negative pressure introduction chamber 28 side is the negative pressure introduction chamber 28 of the communication pipe 4. When contacting the inner peripheral surface on the side, the channel area becomes the maximum value (see FIG. 5).
For this reason, the intake pulsation, which is generated along with the intake operation of the engine 10 and propagates to the gas existing in the clean side intake duct 14, is propagated to the elastic body 6, and the elastic body 6 vibrates in the out-of-plane direction. Then, the increased intake sound is radiated into the outside air from the other opening end of the communication pipe 4 (see FIG. 1).
Therefore, at the time of rapid acceleration, the flow path area becomes the maximum value, and the elastic body 6 vibrates in the out-of-plane direction due to the intake pulsation propagated to the elastic body 6, so that the intake sound that contributes to the acceleration feeling is increased. (See FIG. 5).

(Effect of the second embodiment)
(1) In the intake sound adjusting device of the present embodiment, the displacement means is connected to the negative pressure introduction chamber, the negative pressure introduction chamber, and connected to the flow passage area changing portion, and is changed by the change of the engine side intake negative pressure. It is formed by an elastic film part that is elastically deformed outward to displace the flow path area changing part.
For this reason, compared with the intake sound control device of the first embodiment described above, it is possible to reduce the effect of increasing the intake sound with a simple configuration at the time of slow acceleration and idling where quietness is desired to be ensured. . On the other hand, at the time of rapid acceleration where the driver's willingness to accelerate is strong, the increased intake sound can be radiated into the outside air from the other opening end of the communication pipe.
As a result, as compared with the intake sound adjusting device of the first embodiment described above, a simple configuration makes it possible to ensure quietness during slow acceleration and idling and to increase intake sound during sudden acceleration. It becomes possible.

(2) Further, in the intake sound adjusting device of the present embodiment, one end of the first cylinder portion constituting portion is attached to a position closer to the clean side air intake duct than the elastic body in the outer peripheral surface of the communication pipe. In communication with the communication pipe.
As a result, the airtightness of the space formed by the outer peripheral surface of the communication pipe, the first cylinder portion constituting portion, and the elastic membrane portion can be maintained with a simple configuration, and the elastic membrane portion due to engine-side intake negative pressure It is possible to reliably generate elastic deformation.

(Application example)
(1) In addition, in the intake sound adjusting device 1 of the present embodiment, one end portion of the first cylinder portion constituting portion 40 is attached to the outer peripheral surface of the communicating tube 4 and communicated with the communicating tube 4. However, the present invention is not limited to this. That is, it is good also as a structure which one end part of the 1st cylinder part structure part 40 is obstruct | occluded and is not connected with the communicating pipe 4. FIG. In this case, for example, an opening portion through which the connecting member 38 can be inserted is formed on the outer peripheral surface of the communication pipe 4, and a means capable of maintaining an airtight state between the opening portion and the connecting member 38 is provided. To do.

(2) In addition, in the intake sound adjusting device 1 of the present embodiment, the elastic film portion 44 is sandwiched between the first cylinder portion constituting portion 40 and the second cylinder portion constituting portion 42, but this is not limitative. Not what you want. That is, the elastic film part 44 may be constituted by a single cylindrical member, and the elastic body 6 may be attached to the inner peripheral surface thereof by adhesion or the like, and the cylinder part 36 may be closed.

(Third embodiment)
(Constitution)
Next, a third embodiment of the present invention will be described.
6 and 7 are diagrams showing the configuration of the intake sound adjusting device 1 of the present embodiment. FIG. 6 is a diagram showing the state of the flow path area changing means 8 during slow acceleration and idling. FIG. FIG. 6 is a diagram showing a state of the flow path area changing means 8 during rapid acceleration.
As shown in FIGS. 6 and 7, the configuration of the intake sound adjusting device 1 of the present embodiment is the same as that of the first embodiment described above except for the configuration of the flow path area changing means 8. Since the configuration other than the flow path area changing means 8 is the same as that of the first embodiment described above, the description thereof is omitted.

  The intake sound adjustment device 1 of the present embodiment includes two flow path area changing means 8a and 8b. In FIG. 6 and FIG. 7 and in the following description, of the two flow passage area changing means 8a and 8b, the flow passage area changing means 8 arranged on the air cleaner side is referred to as “flow passage area changing means 8a”. Will be described. Of the two flow path area changing means 8a and 8b, the flow path area changing means 8 arranged on the engine side will be described as “flow path area changing means 8b”.

  Each channel area changing means 8a, 8b includes channel area changing portions 24a, 24b and displacement means 26a, 26b, respectively. In FIG. 6 and FIG. 7 and in the following description, the flow channel area changing unit 24 included in the flow channel area changing unit 8a is referred to as “flow channel area changing unit 24a”, and the displacement unit 26 is referred to as “displacement unit 26a”. I will explain. Further, the flow path area changing unit 24 included in the flow path area changing unit 8b will be described as “flow channel area changing unit 24b” and the displacement unit 26 will be described as “displacement unit 26b”.

The flow path area changing portions 24a and 24b are both disposed closer to the clean side intake duct 14 than the elastic body 6 in the communication pipe 4, and face each other across the central axis of the communication pipe 4. Yes.
Each of the flow path area changing portions 24a and 24b is a substantially semicircular plate-like member that is formed in a shape that closes the communication tube 4 in a state where the end portions on the elastic body 6 side are in contact with each other. Is formed by.

  Further, the flow path area changing portions 24a and 24b are respectively in the length direction of the communication pipe 4 with respect to the communication pipe 4 on the inner peripheral surface of the communication pipe 4 on the negative pressure introduction chambers 28a and 28b described later. It is supported so that it can be displaced by rotating around an axis that intersects. In FIGS. 6 and 7, the rotation centers of the flow path area changing portions 24a and 24b with respect to the communication pipe 4 are shown with reference numerals “Pa” and “Pb”, respectively.

When each flow path area changing portion 24a, 24b is rotated and displaced in the communication pipe 4, the flow path area changes. In FIG. 6, as in FIG. 2, the displacement direction of the flow path area changing portion 24 is represented by a semicircular arrow.
Specifically, the flow path area changing portions 24 a and 24 b are rotated and displaced in the communication pipe 4, and the longitudinal direction of the flow path area changing portions 24 a and 24 b is inclined with respect to the length direction of the communication pipe 4. Then, as the inclination angle of both increases, the opening degree of the communication pipe 4 decreases, and the flow path area decreases from the maximum value.

  The inclination angle of the longitudinal direction of each flow passage area changing portion 24a, 24b with respect to the length direction of the communication pipe 4 increases, and as shown in FIG. 6, the elastic body 6 side of each flow passage area changing portion 24a, 24b. When the end portions of the communication pipes come into contact with each other, the opening degree of the communication pipe 4 becomes the minimum value. In this state, the space between the clean side intake duct 14 and the elastic body 6 is closed, and the flow path area becomes the minimum value. 6 shows a state in which the throttle chamber 18 is closed as in FIG.

Further, when the flow passage area changing portions 24 a and 24 b are rotated and displaced in the communication pipe 4, the longitudinal direction of the flow passage area changing portions 24 a and 24 b is inclined with respect to the length direction of the communication pipe 4. From the present state, the opening degree of the communication pipe 4 increases as it becomes parallel to the length direction of the communication pipe 4. For this reason, the channel area approaches the maximum value.
Then, as shown in FIG. 7, when the longitudinal direction of each flow path area changing portion 24a, 24b is parallel to the length direction of the communication pipe 4, the negative pressure introduction chamber 28 of each flow passage area changing portion 24a, 24b. The side surfaces are in contact with the inner peripheral surface of the communication pipe 4 on the negative pressure introduction chamber 28 side. In this state, the opening degree of the communication pipe 4 is the maximum value, and the flow path area is the maximum value. FIG. 7 shows a state where the opening degree of the throttle chamber 18 is maximum, as in FIG.

  Each displacement means 26a, 26b includes negative pressure introduction chambers 28a, 28b and elastic film portions 44a, 44b, respectively. 6 and FIG. 7 and the following description, the negative pressure introduction chamber 28 provided in the displacement means 26a is described as “negative pressure introduction chamber 28a”, and the elastic film portion 44 is described as “elastic film portion 44a”. . Further, the negative pressure introduction chamber 28 provided in the displacement means 26b will be described as “negative pressure introduction chamber 28b”, and the elastic film portion 44 will be described as “elastic film portion 44b”.

  Each of the negative pressure introduction chambers 28a and 28b includes an introduction pipe portion 34a and 30b and a cylinder portion 36a and 32b, respectively. In FIG. 6 and FIG. 7 and in the following description, the introduction pipe part 34 constituting the negative pressure introduction chamber 28a is described as “introduction pipe part 34a”, and the cylinder part 36 is described as “cylinder part 36a”. Further, the introduction pipe part 34 constituting the negative pressure introduction chamber 28b will be described as “introduction pipe part 34b”, and the cylinder part 36 will be described as “cylinder part 36b”.

The introduction pipe part 34a is formed of, for example, a steel pipe and has a cylindrical shape.
One end of the introduction pipe portion 34 a is attached to a position closer to the engine 10 than the throttle chamber 18 on the outer peripheral surface of the clean side intake duct 14 and communicates with the clean side intake duct 14. The other end portion of the introduction pipe portion 34a communicates with the cylinder portion 36a.

The cylinder part 36a is comprised from the 1st cylinder part structure part 40a by the side of the communication pipe 4, and the 2nd cylinder part structure part 42a farther from the communication pipe 4 than the 1st cylinder part structure part 40a.
Both the first cylinder portion constituting portion 40a and the second cylinder portion constituting portion 42a are formed of a steel pipe and have a cylindrical shape having a diameter larger than that of the introduction tube portion 34a, and the axis is the length of the clean side intake duct 14. They are arranged in parallel with the vertical direction.

One end portion of the first cylinder portion constituting portion 40 a is attached to a position closer to the clean side air intake duct 14 than the elastic body 6 on the outer peripheral surface of the communication tube 4 and communicates with the communication tube 4. The other end portion of the first cylinder portion constituting portion 40a communicates with one end portion of the second cylinder portion constituting portion 42a.
The other end portion of the second cylinder portion constituting portion 42a communicates with the other end portion of the introduction pipe portion 34a. That is, the introduction pipe portion 34a and the cylinder portion 36a communicate with each other.

The introduction pipe portion 34b is formed of a steel pipe and has a cylindrical shape like the introduction pipe portion 34a.
One end of the introduction pipe portion 34b is attached to a position near the clean side air intake duct 14 and the second cylinder part constituting portion 42a on the outer peripheral surface of the introduction pipe portion 34a, and the introduction pipe portion 34a Communicate. The other end of the introduction pipe part 34b communicates with the cylinder part 36b.

The cylinder part 36b is disposed closer to the clean side air intake duct 14 than the communication pipe 4, and faces the cylinder part 36a across the central axis of the communication pipe 4.
Moreover, the cylinder part 36b is comprised from the 1st cylinder part structure part 40b by the side of the communication pipe 4, and the 2nd cylinder part structure part 42b far from the communication pipe 4 rather than the 1st cylinder part structure part 40b.

Both the first cylinder portion constituting portion 40b and the second cylinder portion constituting portion 42b are formed of a steel pipe and have a cylindrical shape having a diameter larger than that of the introduction tube portion 34b, and the axis is the length of the clean side intake duct 14. They are arranged in parallel with the vertical direction.
One end portion of the first cylinder portion constituting portion 40 b is attached to a position closer to the clean side air intake duct 14 than the elastic body 6 on the outer peripheral surface of the communication tube 4 and communicates with the communication tube 4. The other end portion of the first cylinder portion constituting portion 40b communicates with one end portion of the second cylinder portion constituting portion 42b.

The other end portion of the second cylinder portion constituting portion 42b communicates with the other end portion of the introduction pipe portion 34b. That is, the introduction pipe portion 34b and the cylinder portion 36b communicate with each other.
Each of the elastic film portions 44a and 44b is a plate-like member formed in a circular shape by an elastic resin material such as rubber, and has elasticity that elastically deforms in the out-of-plane direction due to a change in engine-side intake negative pressure. In FIG. 6, as in FIG. 2, the flow of the engine-side intake negative pressure is represented by a white arrow.

  Further, the elastic film portions 44a and 44b have their outer peripheral portions sandwiched between the first cylinder portion constituting portions 40a and 40b and the second cylinder portion constituting portions 42a and 42b, respectively, and the cylinder portions 36a and 32b. It is attached to the inner peripheral surface. The elastic film portions 44a and 44b close the negative pressure introduction chambers 28a and 28b, specifically, the cylinder portions 36a and 32b, respectively.

The elastic film portions 44a and 44b are connected to the flow path area changing portions 24a and 24b via connecting members 38a and 38b formed in a bar shape, respectively.
Each of the connecting members 38a and 38b has one end attached at a right angle to the flow passage area changing portions 24a and 24b, and the other end connected to the communicating tube 4 side of the elastic membrane portions 44a and 44b. It is attached to the surface.
The elasticity of each of the elastic membrane portions 44a and 44b is set to a value that elastically deforms toward the second cylinder portion constituting portions 42a and 42b in a state where the engine-side intake negative pressure is equal to or higher than a predetermined pressure.

  When the elastic membrane portions 44a and 44b are elastically deformed toward the second cylinder portion constituting portions 42a and 42b, the flow passage area changing portions 24a and 24b rotate so that the flow passage area decreases from the maximum value. To displace. In this case, as shown in FIG. 6, the elasticity of the elastic film portions 44a and 44b is such that the flow passage area changing portions 24a and 24b are rotated and displaced in the communication pipe 4, and the flow passage area changing portions 24a and 24b It is set as the value which the edge part by the side of the elastic body 6 of 24b contacts mutually. That is, the elasticity of each elastic film part 44a, 44b is a value that elastically deforms toward the second cylinder part constituting part 42a, 42b until the space between the clean side intake duct 14 and the elastic body 6 is closed. Yes.

In addition, the elasticity of each of the elastic film portions 44a and 44b is set to a value that elastically deforms toward the communication pipe 4 in a state where the engine-side intake negative pressure is less than a predetermined pressure. In this case, as shown in FIG. 7, the elasticity of the elastic membrane portion 44a is such that the flow path area changing portion 24a rotates in the communication pipe 4 and the flow passage area changing portion 24a is on the negative pressure introduction chamber 28a side. The surface is set to a value in contact with the inner peripheral surface of the communication pipe 4 on the negative pressure introduction chamber 28a side. Similarly, as shown in FIG. 7, the elasticity of the elastic membrane portion 44b is such that the flow passage area changing portion 24b rotates within the communication pipe 4 and the flow passage area changing portion 24b is on the negative pressure introduction chamber 28b side. The surface is set to a value in contact with the inner peripheral surface of the communication pipe 4 on the negative pressure introduction chamber 28b side. That is, the elasticity possessed by each of the elastic film portions 44a and 44b is a value that elastically deforms toward the communication tube 4 until the flow path area reaches the maximum value.
When the elastic membrane portions 44a and 44b are elastically deformed toward the communication pipe 4, the flow passage area changing portions 24a and 24b rotate so that the flow passage area becomes the maximum value as shown in FIG. To displace.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the intake sound adjustment device 1 of the present embodiment will be described. In the following description, since the configuration other than the flow path area changing means 8 is the same as that of the first embodiment described above, the operation of different parts will be mainly described.
When the engine 10 is driven, the intake pulsation generated by the intake operation of the engine 10 is propagated to the gas present in the clean side intake duct 14 via each intake manifold 22 and the surge tank 20 (FIG. 1). reference).
Here, at the time of idling or slow acceleration, since the opening degree of the throttle chamber 18 is small, the engine-side intake negative pressure becomes equal to or higher than a predetermined pressure, and the inside of the negative pressure introduction chamber 28 becomes negative pressure. Therefore, the elastic film portions 44a and 44b are elastically deformed toward the second cylinder portion constituting portions 42a and 42b, respectively (see FIG. 6).

When the elastic film portions 44a and 44b are elastically deformed toward the second cylinder portion constituting portions 42a and 42b, the flow passage area changing portions 24a and 24b communicate with each other so that the flow passage area is reduced from the maximum value. It rotates around an axis that intersects the length direction of the tube 4 (see FIG. 6).
When each flow path area changing portion 24a, 24b rotates around an axis intersecting the length direction of the communication pipe 4, each flow path area changing section 24a, 24b rotates and displaces in the communication pipe 4, and the flow path area Is reduced below the maximum value (see FIG. 6).

At this time, when the end portions on the elastic body 6 side of the flow path area changing portions 24a and 24b come into contact with each other, the space between the clean side intake duct 14 and the elastic body 6 is closed, and the flow path area becomes the minimum value. (See FIG. 6).
Therefore, the vibration of the elastic body 6 is suppressed by suppressing the propagation of the intake air pulsation generated in the intake operation of the engine 10 to the gas existing in the clean side intake duct 14 to the elastic body 6. (See FIG. 6).

Therefore, at the time of idling and slow acceleration, the flow passage area decreases from the maximum value, and the propagation of the intake pulsation propagated to the gas existing in the clean side intake duct 14 to the elastic body 6 is suppressed. 6 is suppressed, it is possible to reduce the effect of increasing the intake sound (see FIG. 6).
Further, during idling and slow acceleration, the space between the clean-side intake duct 14 and the elastic body 6 is closed, and the flow passage area becomes the minimum value. Therefore, the effect of increasing the intake noise can be greatly reduced. It becomes possible, and the intake sound introduced into the vehicle interior is slight (see FIG. 6).

On the other hand, at the time of rapid acceleration, since the opening degree of the throttle chamber 18 is large, the engine-side intake negative pressure becomes less than a predetermined pressure, and the inside of the negative pressure introduction chamber 28 approaches from the negative pressure to the positive pressure. 44a and 44b are elastically deformed to the communication pipe 4 side (see FIG. 7).
When the elastic membrane portions 44a and 44b are elastically deformed toward the communication tube 4, the flow path area changing portions 24a and 24b rotate around the axis intersecting the length direction of the communication tube 4 to thereby clean-side intake air. The duct 14 and the elastic body 6 communicate with each other (see FIG. 7).
And the longitudinal direction of each flow path area change part 24a, 24b becomes parallel to the length direction of the communicating pipe 4, and the surface by the side of the negative pressure introduction chamber 28a, 28b of each flow path area change part 24a, 24b is respectively The negative pressure introduction chambers 28a and 28b of the communication pipe 4 are in contact with the inner peripheral surface. In this state, the channel area becomes the maximum value (see FIG. 7).

For this reason, the intake pulsation, which is generated along with the intake operation of the engine 10 and propagates to the gas existing in the clean side intake duct 14, is propagated to the elastic body 6, and the elastic body 6 vibrates in the out-of-plane direction. Then, the increased intake sound is radiated into the outside air from the other opening end of the communication pipe 4 (see FIG. 1).
Therefore, at the time of rapid acceleration, the flow path area becomes the maximum value, and the elastic body 6 vibrates in the out-of-plane direction due to the intake pulsation propagated to the elastic body 6, so that the intake sound that contributes to the acceleration feeling is increased. (See FIG. 7).

(Effect of the third embodiment)
(1) The intake sound adjusting device 1 of the present embodiment has a configuration including two flow path area changing means. When the engine-side intake negative pressure is equal to or higher than a predetermined pressure, two flow paths are provided. The area changing portion closes the space between the clean side intake duct and the elastic body.
For this reason, as compared with the case where the gap between the clean side suction duct and the elastic body is blocked by one flow path area changing portion, the gap between the clean side suction duct and the elastic body is reliably blocked. Is possible.
As a result, in a state where the engine-side intake negative pressure is equal to or higher than the predetermined pressure, that is, at the time of slow acceleration and idling where quietness is desired to be ensured, it is possible to reliably reduce the effect of increasing the intake noise. Can be secured.
(Application example)
(1) In addition, in the intake sound adjusting device 1 of the present embodiment, the two flow area changing means 8a and 8b are provided. However, the present invention is not limited to this. It is good also as a structure provided with the means 8. FIG. In short, the configuration may include a plurality of flow path area changing means 8.

(Fourth embodiment)
(Constitution)
Next, a fourth embodiment of the present invention will be described.
8 and 9 are diagrams showing the configuration of the intake sound adjusting device 1 of the present embodiment. FIG. 8 is a diagram showing the state of the flow path area changing means 8 during slow acceleration and idling. FIG. FIG. 6 is a diagram showing a state of the flow path area changing means 8 during rapid acceleration.
As shown in FIGS. 8 and 9, the configuration of the intake sound adjusting device 1 of the present embodiment is the first embodiment described above except that it includes a gas movement control valve 46 and a control valve switching command unit 48. It has the same configuration as the form. Since the configuration other than the gas movement control valve 46, the control valve switching command unit 48, and the portion related to both is the same as that of the first embodiment described above, the description thereof is omitted.

The gas movement control valve 46 is formed by an electronic control valve, for example, and is disposed between the introduction pipe portion 34 and the cylinder portion 36. That is, the gas movement control valve 46 is disposed between the clean side intake duct 14 and the closing plate 30. A negative pressure tank 50 that stores the negative pressure generated in the clean side intake duct 14 is disposed between the gas movement control valve 46 and the introduction pipe portion 34.
In addition, when the gas movement control valve 46 receives a switching command signal transmitted from the control valve switching command unit 48, the gas movement control valve 46 has a function capable of switching between an allowable state and a cutoff state in accordance with the switching command signal.

  As shown in FIG. 8, the allowable state is a state where the introduction pipe portion 34 and the cylinder portion 36 are in communication with each other, and the communication between the clean side intake duct 14 and the negative pressure introduction chamber 28 is allowed. It is. In FIG. 8, as in FIG. 2, the displacement direction of the flow path area changing portion 24 is represented by a semicircular arrow. 8 shows a state in which the throttle chamber 18 is closed as in FIG.

In a state where the communication between the clean side intake duct 14 and the negative pressure introduction chamber 28 is allowed, the closing plate urging means 32 is disposed in the cylinder portion 36 due to the negative pressure stored in the negative pressure tank 50. The space is negative pressure. In FIG. 8, as in FIG. 2, the flow of the engine-side intake negative pressure is represented by a white arrow.
On the other hand, as shown in FIG. 9, the shut-off state is a state in which the space between the introduction pipe portion 34 and the cylinder portion 36 is shut off, and the clean-side intake duct 14 and the negative pressure introduction chamber 28 are shut off. It is. 9 shows a state in which the opening degree of the throttle chamber 18 is maximum, as in FIG.

In a state where the clean side intake duct 14 and the negative pressure introduction chamber 28 are blocked, the space in the cylinder portion 36 where the closing plate urging means 32 is arranged approaches the positive pressure from the negative pressure.
The control valve switching command unit 48 is formed by, for example, an ECU (engine control unit) that is an existing configuration in the vehicle, and includes an engine rotation information detection unit, a switching condition determination unit, and a switching command signal transmission unit. Yes. In FIGS. 8 and 9, the engine rotation information detecting means, the switching condition determining means, and the switching command signal transmitting means are not shown.

  The engine rotation information detection means receives an information signal including engine rotation information detected by an engine rotation information sensor (not shown) attached to the engine as the engine rotation information signal when the engine is driven. And it has a function which transmits this received engine-rotation information signal to a switching condition determination means. In the present embodiment, a case will be described in which the engine rotation information is the engine speed.

When the engine speed information signal is received, the switching condition determination means determines whether the state of the gas movement control valve 46 is set to an allowable state or a cut-off state based on the engine rotation information included in the received signal. Then, the information signal including the determination result is transmitted to the switching command signal transmission unit as the determination result signal.
Specifically, a predetermined rotational speed is stored in advance, and the engine rotational speed transmitted from the engine rotational information detecting means is compared with the predetermined rotational speed.

Here, the “predetermined number of revolutions” means that the amount of inspiration sound is low during slow acceleration when the accelerator pedal is depressed by the driver and the driver's willingness to accelerate is weak, or during idling when the driver does not depress the accelerator pedal. This is the engine speed in a situation that is inappropriate for increasing the sound.
Then, when the engine speed is less than the predetermined engine speed, it is determined that the gas movement control valve 46 is switched to the allowable state, and the determination result signal indicates that the gas movement control valve 46 is switched to the allowable state. Enter.

On the other hand, when the engine speed is equal to or higher than the predetermined engine speed, it is determined that the gas movement control valve 46 is switched to the shut-off state, and the determination result signal indicates that the gas movement control valve 46 is switched to the shut-off state. Enter.
When receiving the determination result signal, the switching command signal transmission means transmits an information signal including the determination result to the gas movement control valve 46 as a switching command signal.
That is, the control valve switching command unit 48 has a function of switching between an allowable state and a cutoff state according to engine rotation information.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of this embodiment will be described. In the following description, since the configuration other than the flow path area changing means 8 and the gas movement control valve 46 is the same as that of the first embodiment described above, the operation of different parts will be mainly described.
When the engine 10 is driven, the intake pulsation generated by the intake operation of the engine 10 is propagated to the gas present in the clean side intake duct 14 via each intake manifold 22 and the surge tank 20 (FIG. 1). reference).
Here, at the time of idling or slow acceleration, since the opening degree of the throttle chamber 18 is small, the engine-side intake negative pressure becomes equal to or higher than a predetermined pressure, and the inside of the negative pressure introduction chamber 28 becomes negative (see FIG. 8).

Further, since the engine speed is less than the predetermined engine speed during idling or slow acceleration, the control valve switching command unit 48 switches the gas movement control valve 46 to an allowable state (see FIG. 8).
When the gas movement control valve 46 is allowed, the communication between the clean side intake duct 14 and the negative pressure introduction chamber 28 is allowed, so that the gas flow between the clean side intake duct 14 and the negative pressure introduction chamber 28 is allowed. Movement is allowed (see FIG. 8).

Then, due to the negative pressure generated in the clean side intake duct 14 stored in the negative pressure tank 50, the space in the cylinder portion 36 where the closing plate urging means 32 is arranged becomes negative pressure (FIG. 8).
When the space in the cylinder portion 36 where the closing plate urging means 32 is arranged becomes negative pressure, the closing plate urging means 32 contracts and the closing plate 30 slides against the inner peripheral surface of the cylinder portion 36. Then, it moves to the bottom side of the cylinder part 36 (see FIG. 8).

When the closing plate 30 moves to the bottom surface side of the cylinder portion 36, the flow path area changing portion 24 rotates and displaces in the communication pipe 4, and the flow path area decreases from the maximum value (see FIG. 8).
At this time, when the flow path area changing portion 24 comes into contact with the inner peripheral surface of the communication pipe 4, the space between the clean side intake duct 14 and the elastic body 6 is closed, and the flow path area becomes the minimum value (see FIG. 8). ).
Therefore, the vibration of the elastic body 6 is suppressed by suppressing the propagation of the intake air pulsation generated in the intake operation of the engine 10 to the gas existing in the clean side intake duct 14 to the elastic body 6. (See FIG. 8).

Therefore, at the time of idling and slow acceleration, the flow passage area decreases from the maximum value, and the propagation of the intake pulsation propagated to the gas existing in the clean side intake duct 14 to the elastic body 6 is suppressed. 6 is suppressed, the effect of increasing the intake sound can be reduced (see FIG. 8).
Further, during idling and slow acceleration, the space between the clean-side intake duct 14 and the elastic body 6 is closed, and the flow passage area becomes the minimum value. Therefore, the effect of increasing the intake noise can be greatly reduced. It becomes possible, and the intake sound introduced into the vehicle interior is slight (see FIG. 8).

On the other hand, during sudden acceleration, since the opening of the throttle chamber 18 is large, the intake negative pressure generated in the gas in the clean side intake duct 14 during the intake process of the engine is higher than during slow acceleration, and the engine side The intake negative pressure is less than a predetermined pressure (see FIG. 9).
Further, at the time of rapid acceleration, since the engine speed becomes equal to or higher than the predetermined engine speed, the control valve switching command unit 48 switches the gas movement control valve 46 to the shut-off state (see FIG. 9).

When the gas movement control valve 46 is cut off, the clean side intake duct 14 and the negative pressure introduction chamber 28 are cut off, and the movement of gas between the clean side intake duct 14 and the negative pressure introduction chamber 28 is cut off. (See FIG. 9).
In the cylinder portion 36, the space in which the closing plate urging means 32 is arranged approaches the positive pressure from the negative pressure, the closing plate urging means 32 extends, and the closing plate 30 is connected to the inner periphery of the cylinder portion 36. It slides with respect to the surface and moves to the communication pipe 4 side (see FIG. 9).

When the blocking plate 30 moves to the communication pipe 4 side, the flow path area changing portion 24 rotates and displaces in the communication pipe 4 and moves away from the inner peripheral surface of the communication pipe 4. The clean side air intake duct 14 and the elastic body 6 communicate with each other (see FIG. 9).
At this time, when the clean side intake duct 14 and the elastic body 6 communicate with each other and the longitudinal direction of the flow path area changing portion 24 is parallel to the length direction of the communication pipe 4, the flow path area becomes the maximum value. (See FIG. 9).

For this reason, the intake pulsation, which is generated along with the intake operation of the engine 10 and propagates to the gas existing in the clean side intake duct 14, is propagated to the elastic body 6, and the elastic body 6 vibrates in the out-of-plane direction. Then, the increased intake sound is radiated into the outside air from the other opening end of the communication pipe 4 (see FIG. 1).
Therefore, at the time of rapid acceleration, the flow path area becomes the maximum value, and the elastic body 6 vibrates in the out-of-plane direction due to the intake pulsation propagated to the elastic body 6, so that the intake sound that contributes to the acceleration feeling is increased. (See FIG. 9).

(Effect of the fourth embodiment)
(1) In the intake sound adjusting device of the present embodiment, the control valve switching command unit allows the communication between the intake duct and the negative pressure introduction chamber according to the engine rotation information, the intake duct and the negative pressure. Switch the shutoff state to shut off the introduction room.
For this reason, in addition to the change in the engine-side intake negative pressure, the displacement state of the flow path area changing portion can be controlled in accordance with the engine rotation information, and the flow path area can be changed. .
As a result, compared with the intake sound control device of the first to third embodiments described above, both quietness at the time of slow acceleration and idling and the sound increase of the intake sound at the time of sudden acceleration are both compatible with high accuracy. It becomes possible to do.

(2) Further, in the intake sound adjusting device of the present embodiment, the engine rotation information is the engine speed. Further, the control valve switching command unit switches the gas movement control valve to an allowable state in a state where the engine speed is less than a predetermined speed, and the engine speed is equal to or higher than the predetermined speed. Switch the gas movement control valve to the shut-off state.
As a result, according to the engine speed, it is possible to accurately ensure quietness during idling and slow acceleration and to improve the sound increase effect during sudden acceleration.

(Application example)
(1) The intake sound adjustment device 1 according to the present embodiment is similar to the intake sound adjustment device 1 according to the first embodiment described above, and includes an obstruction plate 30 and an obstruction plate urging means 32. However, the present invention is not limited to this. That is, the present invention may be applied to an intake sound adjusting device having a configuration including the elastic film portion 44 as in the intake sound adjusting device 1 of the second and third embodiments described above. (2) In addition, in the intake sound adjusting device 1 of the present embodiment, the control valve switching command unit 48 is formed by the ECU that is an existing configuration in the vehicle, but the present invention is not limited to this, and the control valve switching command unit is not limited thereto. As 48, it is good also as a structure provided with exclusive ECU.

(3) Further, in the intake sound adjusting device 1 of the present embodiment, the rotation information of the engine 10 is the rotation speed of the engine 10, but the rotation information of the engine 10 is not limited to this. That is, for example, the vehicle speed may be used as the rotation information of the engine 10, for example. Further, as the rotation information of the engine 10, for example, the torque of the engine 10 may be used.
(4) Further, in the intake sound adjusting device 1 of the present embodiment, the negative pressure tank 50 is disposed between the gas movement control valve 46 and the introduction pipe portion 34, but the present invention is not limited to this. A configuration in which the tank 50 is not provided may be employed.

(Fifth embodiment)
(Constitution)
Next, a fifth embodiment of the present invention will be described.
10 to 12 are diagrams showing the configuration of the intake sound adjustment device 1 of the present embodiment, and FIG. 10 is a diagram showing the overall configuration of the intake sound adjustment device 1. FIG. 11 is a view showing the state of the flow path area changing means 8 during slow acceleration and idling, and FIG. 12 is a view showing the state of the flow path area changing means 8 during sudden acceleration.
As shown in FIGS. 10 to 12, the configuration of the intake sound adjusting device 1 of the present embodiment is provided with a support member 52, and the configuration of the flow path area changing means 8 and the second communication pipe constituting portion 4 b. The configuration is the same as that of the first embodiment described above. In addition, since it is the structure similar to 1st Embodiment mentioned above except the support member 52, the flow-path area change means 8, and the part relevant to both, description is abbreviate | omitted.

As shown in FIG. 10, the flow path area changing means 8 is attached to the second communication pipe constituting portion 4 b and arranged on the outside air side from the elastic body 6.
The support member 52 is formed in a columnar shape using a material having high rigidity such as a metal material, for example. One end of the support member 52 is fixed to the flow path area changing means 8, and the other end of the support member 52 is a component (not shown) disposed in the engine room, such as an engine body or a subframe. )). Thereby, the support member 52 suppresses the displacement of the flow path area changing means 8 in the engine room where the engine 10 is arranged.

The flow path area changing unit 8 includes a gear rotating unit 54 and a rotation state control unit 56. The configuration of the gear rotation means 54 and the rotation state control unit 56 will be described later.
Further, as shown in FIGS. 11 and 12, the flow path area changing means 8 includes a flow path area changing portion 24, a rotating shaft 58, and a gear 60. In FIG. 11 and FIG. 12, illustrations other than the flow path area changing means 8 and the second communication pipe component 4 b are omitted for the sake of explanation.
The flow path area changing portion 24 is arranged on the outside air side of the elastic body 6 in the second communication pipe constituting portion 4b.

The flow path area changing portion 24 is formed by a plate-like member having a shape corresponding to the cross-sectional shape of the second communication pipe constituting portion 4b, and includes a main body portion 62 and a shape changing portion 64. The main body portion 62 and the shape changing portion 64 are formed integrally.
The shape changing portion 64 is a shape in which the length from the center of gravity of the flow path area changing portion 24 to the edge changes, specifically, the second communicating tube constituting portion 4b when viewed from the axial direction of the second communicating tube constituting portion 4b. It is formed in a substantially crescent moon shape in which the length from the center of gravity to the edge increases with increasing distance from the inner peripheral surface of 4b. Therefore, the shape changing portion 64 is formed so that the flow path area changing portion 24 is elliptical when viewed from the axial direction of the second communication pipe constituting portion 4b.

  The rotating shaft 58 passes through the second communication pipe component 4b in the radial direction, and is disposed inside the second communication pipe component 4b with the shaft directed in the radial direction of the second communication pipe component 4b. The flow path area changing section 24 is fixed. The fixed portion of the rotation shaft 58 to the flow channel area changing unit 24 includes the center of gravity of the flow channel area changing unit 24. Thereby, the rotating shaft 58 can displace the flow path area changing portion 24 by rotating around the axis intersecting the length direction of the second communicating pipe constituting portion 4b with respect to the second communicating pipe constituting portion 4b. To support.

One end of the rotary shaft 58 is connected to the gear 60 outside the second communication pipe component 4b.
The gear 60 has a gap 66 that does not form teeth in a part of the outer circumferential surface on which a plurality of teeth are formed. That is, the gear 60 has teeth only in a part of the outer peripheral surface in the circumferential direction. In FIG. 11 and FIG. 12, the illustration of a gear box that protects the gear 60 is omitted for the sake of explanation.

The gear rotation means 54 includes a meshing portion that meshes with the gear 60 and a rotation drive unit that rotates the meshing portion. The rotation drive unit is formed by a motor or the like, for example. In addition, in FIG. 10, illustration of a meshing part and a rotation drive part is abbreviate | omitted. 11 and 12, the gear rotation means 54 is not shown.
When the rotation driving unit receives the rotation state control signal transmitted from the rotation state control unit 56, the rotation driving unit has a function of rotating the meshing unit according to the rotation state control signal. When the meshing portion is rotationally driven, the gear 60 is rotationally driven. Therefore, the gear rotation means 54 has a function of driving the gear 60 to rotate.

  The rotation state control unit 56 is formed by, for example, an ECU that is an existing configuration in the vehicle, and includes an engine rotation information detection unit, a displacement state calculation unit, and a displacement state control signal transmission unit. In FIG. 10, the engine rotation information detection means, the displacement state calculation means, and the displacement state control signal transmission means are not shown. Further, in FIG. 11 and FIG. 12, the rotation state control unit 56 is not shown.

  The engine rotation information detection means receives an information signal including engine rotation information detected by an engine rotation information sensor (not shown) attached to the engine as the engine rotation information signal when the engine is driven. And it has a function which transmits this received engine-rotation information signal to a displacement state calculating means. In the present embodiment, a case will be described in which the engine rotation information is the engine speed.

When receiving the engine rotation information signal, the displacement state calculation means calculates the displacement state of the flow path area changing unit 24 in the second communication pipe constituting unit 4b based on the engine rotation information included in the received signal. And the information signal containing this calculation result is transmitted to a displacement state control signal transmission means as a displacement state calculation signal.
Specifically, a predetermined rotational speed is stored in advance as in the fourth embodiment, and the engine rotational speed transmitted from the engine rotational information detecting means is compared with the predetermined rotational speed. .

In a state where the engine speed is less than the predetermined speed, the displacement state of the flow path area changing unit 24 is the gear 60 in a state where the flow path area of the second communication pipe component 4b is less than the maximum value. The rotation state is calculated, and information including the calculation result is input to the displacement state calculation signal. As the rotation state of the gear 60, for example, the rotation speed or rotation angle of the gear 60 is used.
On the other hand, in a state where the engine speed is equal to or higher than the predetermined speed, the displacement state of the flow path area changing unit 24 is the rotation of the gear 60 in a state where the flow path area of the second communication pipe component 4b is the maximum value. The state is calculated, and information including the calculation result is input to the displacement state calculation signal.

When the displacement state control signal transmission means receives the displacement state calculation, the displacement state control signal transmission means transmits an information signal including the calculation result described above to the rotation state control unit 56 as a rotation state control signal.
As described above, the rotation state control unit 56 has a function of controlling the driving state of the gear rotation unit 54 in accordance with the rotation information of the engine.
Further, as shown in FIG. 11 and FIG. 12, the inner circumferential surface of the second communication pipe component 4 b has two convex portions due to the step formed by changing the thickness of the second communication pipe component 4 b. Portions 68a and 68b are formed.

As shown in FIG. 11, each of the convex portions 68 a and 68 b is in a state where the flow passage area of the second communication pipe component 4 b is the minimum value on the inner peripheral surface of the second communication pipe component 4 b. It is formed at a site that comes into contact with the flow path area changing portion 24. The state in which the flow channel area of the second communication pipe component 4b is the minimum value is a state in which the flow channel area changing unit 24 is in contact with the inner peripheral surface of the second communication pipe component 4b.
Moreover, the shape of each convex part 68a, 68b is a state where the flow path area of the second communication pipe constituting part 4b is the minimum value, and the flow area is viewed from the axial direction of the second communication pipe constituting part 4b. The change portion 24 and the convex portions 68a and 68b form a shape in which the second communication pipe constituting portion 4b is closed.
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of this embodiment will be described. In the following description, since the configuration other than the flow path area changing means 8 is the same as that of the first embodiment described above, the operation of different parts will be mainly described.
When the engine 10 is driven, the intake pulsation generated by the intake operation of the engine 10 is propagated to the gas present in the clean side intake duct 14 via each intake manifold 22 and the surge tank 20 (FIG. 10). reference).

  Here, at the time of idling or slow acceleration, the rotational speed of the engine becomes less than a predetermined rotational speed. Therefore, the rotational state control unit 56 controls the driving state of the gear rotating means 54 to control the flow path area changing unit 24. The displacement state is a state in which the flow path area of the second communication pipe component 4b is reduced from the maximum value. Specifically, the gear 60 is rotated by the gear rotating means 54, and the flow path area changing portion 24 is inclined with respect to the axial direction of the second communication pipe constituting portion 4b in the second communication pipe constituting portion 4b (see FIG. 11).

And if the inclination angle with respect to the axial direction of the 2nd communicating pipe structure part 4b of the flow path area change part 24 increases, according to this increase, the flow area of the 2nd communicating pipe structure part 4b will reduce from the maximum value. (See FIG. 11).
The inclination angle of the flow passage area changing portion 24 with respect to the axial direction of the second communication pipe constituting portion 4b increases, the flow passage area changing portion 24 comes into contact with the convex portions 68a and 68b, and the inside of the second communication pipe constituting portion 4b. When in contact with the peripheral surface, the flow path area changing section 24 closes between the outside air side and the elastic body 6. In this state, the opening degree of the second communication pipe component 4b becomes the minimum value, and the flow passage area of the second communication pipe component 4b becomes the minimum value (see FIGS. 10 and 11).

For this reason, even if the elastic body 6 vibrates in the out-of-plane direction due to the intake air pulsation that is generated along with the intake operation of the engine 10 and propagates to the gas existing in the clean side intake duct 14, the increased intake air The radiation of sound from the open end of the second communication pipe component 4b into the outside air is suppressed (see FIGS. 10 and 11).
Therefore, when idling and slowly accelerating, the flow passage area decreases from the maximum value, and the increased intake sound is suppressed from being emitted into the outside air, so that the effect of increasing the intake sound can be reduced. (See FIGS. 10 and 11).
In addition, during idling and slow acceleration, the space between the outside air and the elastic body 6 is blocked, and the flow passage area of the second communication pipe component 4b is minimized, so that the sound increase effect of the intake sound is greatly improved. It becomes possible to reduce, and the intake sound introduced into the vehicle interior is slight (see FIGS. 10 and 11).

  On the other hand, at the time of rapid acceleration, the rotational speed of the engine becomes equal to or higher than a predetermined rotational speed, and the intake negative pressure generated by the engine decreases (the absolute value of the intake negative pressure increases). For this reason, the rotation state control unit 56 controls the driving state of the gear rotation means 54 so that the displacement state of the flow channel area changing unit 24 is the state where the flow channel area of the second communication pipe component 4b is the maximum value. And Specifically, the gear 60 is rotated by the gear rotation means 54, and the inclination angle of the flow path area changing unit 24 with respect to the axial direction of the second communication pipe component 4b is reduced in the second communication pipe component 4b. As a result, the flow channel area changing unit 24 is changed from the state in which the flow channel area changing unit 24 is inclined with respect to the axial direction of the second communication pipe component 4b to the axial direction of the second communication pipe component 4b. And incline so as to be parallel (see FIG. 12). In addition, in FIG. 12, the rotation direction of the flow-path area change part 24, the rotating shaft 58, and the gearwheel 60 is shown by the arrow.

And if the inclination angle with respect to the axial direction of the 2nd communicating pipe structure part 4b of the flow path area change part 24 reduces, according to this reduction | decrease, the flow area of the 2nd communicating pipe structure part 4b will approach the maximum value. Increase (see FIG. 12).
When the inclination angle of the flow passage area changing portion 24 with respect to the axial direction of the second communication pipe constituting portion 4b decreases and the flow passage area changing portion 24 becomes parallel to the axial direction of the second communication pipe constituting portion 4b, In the road area changing part 24, the opening degree of the second communication pipe constituting part 4b becomes the maximum value. In this state, the flow path area of the second communication pipe component 4b is the maximum value (see FIG. 12).

For this reason, the intake pulsation, which is generated along with the intake operation of the engine 10 and propagates to the gas existing in the clean side intake duct 14, is propagated to the elastic body 6, and the elastic body 6 vibrates in the out-of-plane direction. Then, the increased intake sound is radiated into the outside air from the opening end of the second communication pipe component 4b (see FIGS. 10 and 12).
Therefore, at the time of sudden acceleration, the flow passage area of the second communication pipe component 4b becomes the maximum value, and the elastic body 6 vibrates in the out-of-plane direction due to the intake pulsation propagated to the elastic body 6. It is possible to increase the contributing intake sound (see FIGS. 10 and 12).

(Effect of the fifth embodiment)
(1) In the intake sound adjusting device of the present embodiment, the flow path area changing portion is arranged on the outside air side of the elastic body, so that the flow path area changing portion is damaged, and the flow path is changed from the inside of the communication pipe. Even when the component part of the area changing portion is detached, the movement of the detached component part toward the intake passage is blocked by the elastic body.
For this reason, it is possible to prevent the flow path area changing portion from being sucked into the engine.
As a result, even when damage or the like occurs in the flow path area change part, it is possible to avoid a serious failure mode that accompanies the engine stop and avoid a serious safety failure. Become.

(2) Further, in the intake sound adjusting device of the present embodiment, the flow path area changing means is fixed to the vehicle body side member via the support member, so that the flow path area changing means in the engine room where the engine is arranged. The displacement of is suppressed.
As a result, it is possible to suppress interference between the flow path area changing means and a member disposed in the engine room, such as an engine, so that damage to the member disposed in the engine room can be suppressed. .

(3) Further, in the intake sound adjusting device of the present embodiment, the gear rotating means for rotating the gear connected to the rotating shaft fixed to the flow path area changing portion, and the driving of the gear rotating means according to the engine rotation information A rotation state control unit for controlling the state.
For this reason, according to the rotation information of the engine, it is possible to control the rotation state of the flow path area changing unit, and it is possible to change the flow path area of the communication pipe.
As a result, it is possible to accurately achieve quietness during idling and slow acceleration and to improve the sound increase effect during sudden acceleration.

(4) Further, in the intake sound adjusting device of the present embodiment, the engine rotation information is the engine speed. Further, in the state where the rotational state control unit is in a state where the engine rotational speed is less than the predetermined rotational speed, the flow path area is reduced below the maximum value, and the engine rotational speed is equal to or higher than the predetermined rotational speed, The driving state of the gear rotating means is controlled so that the flow path area becomes the maximum value.
As a result, according to the engine speed, it is possible to accurately ensure quietness during idling and slow acceleration and to improve the sound increase effect during sudden acceleration.

(5) Further, in the intake sound adjusting device of the present embodiment, the flow path area changing portion includes a shape changing portion in which the length from the center of gravity to the edge changes when viewed from the axial direction of the communication pipe. Further, the shape changing portion is formed so that the flow channel area changing portion is elliptical when viewed from the axial direction of the communication pipe.
For this reason, in a state where the flow passage area changing portion closes the communication pipe, the angle of the flow passage area changing portion is inclined with respect to the axial direction of the communication pipe, thereby reducing the rotation angle of the flow passage area changing portion. Is possible.
As a result, the flow path area changing portion can be rotated in the communication pipe in a short time, so that it is possible to switch between increasing and suppressing the intake sound with good response.

(6) Further, in the intake sound adjusting device of the present embodiment, the shape change portion is formed so that the flow path area change portion is elliptical when viewed from the axial direction of the communication pipe. In the state where the changing portion is closed, the angle of the flow path area changing portion is inclined with respect to the axial direction of the communication pipe. Further, in the state where the flow path area of the communication pipe is at the maximum value, the angle of the flow path area changing portion is parallel to the axial direction of the communication pipe.
Therefore, the flow passage area changing portion is rotated in the communication pipe so that the flow passage area of the communication pipe changes within the range from the minimum value to the maximum value without forming teeth on the entire outer circumferential surface of the gear. It becomes possible.
Thereby, in the intake sound adjusting device of this embodiment, the configuration of the gear is configured to have teeth only in a part of the outer peripheral surface in the circumferential direction. For this reason, it becomes possible to improve the rotational speed of a gear compared with the case where a tooth | gear is formed in the whole circumferential direction of the outer peripheral surface of a gear.
As a result, the flow path area changing portion can be rotated in the communication pipe in a short time, so that it is possible to switch between increasing and suppressing the intake sound with good response.

(7) Further, in the intake sound adjusting device of the present embodiment, a convex portion that contacts the flow channel area changing portion is formed on the inner peripheral surface of the communication tube in a state where the flow channel area of the communication tube is the minimum value.
For this reason, in a state where the flow passage area changing portion closes the communication pipe, the flow passage area changing portion and the communication pipe can be overlapped with each other in the axial direction of the communication pipe, and proceed in the axial direction of the communication pipe. It is possible to isolate the sound without leaking.
As a result, it is possible to accurately realize the quietness at the time of idling and slow acceleration.

(8) Further, in the intake sound adjusting device of the present embodiment, the convex portion formed on the inner peripheral surface of the communication pipe is a step on the inner peripheral surface of the communication pipe formed by changing the thickness of the communication pipe. .
For this reason, it becomes possible to make it function as a stopper with respect to a flow-path area change part by making a convex part the level | step difference of the internal peripheral surface of a communicating pipe. Further, since the communication pipe and the convex portion are integrated, the rigidity of the convex portion can be increased.
As a result, it is possible to suppress friction between the flow path area changing portion and the inner peripheral surface of the communication pipe, and it is possible to suppress damage to the flow path area changing portion. Moreover, it becomes possible to suppress the damage of a convex part.

(Application example)
(1) In the intake sound adjusting device 1 of the present embodiment, the shape changing portion 64 is formed so that the flow path area changing portion 24 is elliptical when viewed from the axial direction of the second communication pipe constituting portion 4b. However, the present invention is not limited to this. That is, for example, as shown in FIG. 13, the shape changing portion 64 may be formed such that the flow path area changing portion 24 is rectangular when viewed from the axial direction of the second communication pipe constituting portion 4 b. In this case, as shown in FIG. 13, the shape of the communication pipe 4 is formed in a square cross section. In short, the shape changing portion 64 may be formed in a shape in which the length from the center of gravity of the flow path area changing portion 24 to the edge changes as seen from the axial direction of the second communication pipe constituting portion 4b. FIG. 13 is a diagram illustrating a modification of the present embodiment. In addition, in FIG. 13, the rotation direction of the flow path area change part 24 and the rotating shaft 58 is shown by the arrow.

(2) Further, in the intake sound adjusting device 1 of the present embodiment, the rotating shaft 58 is rotated via the gear 60, but the present invention is not limited to this. The rotating shaft 58 may be rotated by changing the pressure.
(3) In addition, in the intake sound adjusting device 1 of the present embodiment, the inner periphery of the communication pipe 4 is formed by changing the thickness of the communication pipe 4 with the convex portion 68 formed on the inner peripheral surface of the communication pipe 4. Although the surface is stepped, the configuration of the convex portion 68 is not limited to this. That is, the convex portion 68 may be formed separately from the communication tube 4 and attached to the inner peripheral surface of the communication tube 4.

It is a figure which shows the structure concept of the intake sound control apparatus 1 of 1st embodiment of this invention. In 1st embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of slow acceleration and idling. In 1st embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of rapid acceleration. In 2nd embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of slow acceleration and idling. In 2nd embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of rapid acceleration. In 3rd embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of slow acceleration and idling. In 3rd embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of rapid acceleration. In 4th embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of slow acceleration and idling. In 4th embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of rapid acceleration. It is a figure which shows the structure concept of the intake sound control apparatus 1 of 5th embodiment of this invention. In 5th embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of slow acceleration and idling. In 5th embodiment of this invention, it is a figure which shows the state of the flow-path area change means 8 at the time of rapid acceleration. It is a figure which shows the example of application of the intake sound control apparatus 1 of 5th embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intake sound adjusting device 2 Intake duct 4 Communication pipe 6 Elastic body 8 Flow path area change means 10 Engine 12 Dust side intake duct 14 Clean side intake duct 16 Air cleaner 18 Throttle chamber 20 Surge tank 22 Intake manifold 24 Change flow area Part 26 Displacement means 28 Negative pressure introduction chamber 30 Blocking plate 32 Blocking plate biasing means 34 Introduction pipe part 36 Cylinder part 38 Connecting member 40 First cylinder part constituting part 42 Second cylinder part constituting part 44 Elastic film part 46 Gas movement control valve 48 Control valve switching command section 50 Negative pressure tank 52 Support member 54 Gear rotation means 56 Rotation state control section 58 Rotating shaft 60 Gear 62 Body section 64 Shape change section 66 Cavity section 68 Convex section P Flow path area change section for the communication pipe 4 24 rotation centers

Claims (23)

An intake sound adjusting device comprising: a communication pipe having one end communicating with an intake passage to the engine and the other end communicating with outside air; and an elastic body closing the communication pipe,
An intake sound adjusting device comprising: a flow passage area changing means for changing a flow passage area of the communication pipe according to a change in intake negative pressure generated in the intake passage.   The flow passage area changing means sets the flow passage area to a maximum value in a state where the intake negative pressure is less than a predetermined pressure, and sets the flow passage area in a state where the intake negative pressure is equal to or greater than a predetermined pressure. The intake sound adjusting device according to claim 1, wherein the intake sound adjusting device is reduced from a maximum value.   The flow passage area changing means is disposed in the communication pipe and is displaced in the communication pipe to change the flow passage area by changing the opening of the communication pipe, and the intake negative pressure. The intake sound adjusting device according to claim 1, further comprising: a displacement unit that displaces the flow path area changing unit according to a change in the flow rate.   The displacement means is attached to a position closer to the engine than a throttle chamber for increasing or decreasing the intake air amount of the engine on the outer peripheral surface of the intake passage, and a negative pressure introduction chamber communicating with the intake passage; The flow passage area changing portion is displaced in a direction in which the opening degree of the communication pipe decreases in a state where the pressure is equal to or higher than the pressure, and the opening degree of the communication pipe increases in a state where the intake negative pressure is less than a predetermined pressure. 4. An intake sound adjusting device according to claim 3, further comprising opening degree changing means for displacing the flow path area changing portion in a direction.   The opening changing means closes the negative pressure introduction chamber and increases the opening of the communication pipe in a state in which the intake negative pressure is less than a predetermined pressure, and a closing plate connected to the flow path area changing portion. 5. The intake sound adjusting device according to claim 4, further comprising: a closing plate urging unit that presses and urges the closing plate so that the flow path area changing portion is displaced in a direction to be moved.   The opening changing means includes an elastic membrane portion that closes the negative pressure introduction chamber and is connected to the flow passage area changing portion and elastically deforms in an out-of-plane direction by a change in the intake negative pressure. The intake sound adjusting device according to claim 4 or 5.   A gas movement control valve capable of switching between a permissible state permitting communication between the intake passage and the negative pressure introduction chamber and a shut-off state interrupting the intake passage and the negative pressure introduction chamber, and according to rotation information of the engine The intake sound adjusting device according to any one of claims 4 to 6, further comprising a control valve switching command unit that switches a state of the gas movement control valve. The engine rotation information is the engine speed,
The control valve switching command unit switches the gas movement control valve to the allowable state in a state where the engine speed is less than a predetermined speed, and the engine speed is equal to or higher than the predetermined speed. 8. The intake sound adjusting device according to claim 7, wherein the gas movement control valve is switched to the shut-off state. The channel area changing means includes a rotating shaft that fixes the axis to the channel area changing portion in a state in which the axis is directed in the radial direction of the communication pipe,
The intake sound adjusting device according to claim 3, wherein the displacement unit includes a rotational driving force generator that rotates the rotation shaft according to a change in the intake negative pressure.   The flow path area changing means is disposed in the communication pipe and is displaced in the communication pipe to change the flow path area by changing the opening of the communication pipe, and the shaft is connected to the communication pipe. Depending on the rotation information of the engine, a rotation shaft fixed to the flow path area changing portion in a state of being directed in the radial direction of the tube, a gear connected to the rotation shaft, a gear rotation means for rotating the gear, and The intake sound adjustment device according to claim 1, further comprising: a rotation state control unit that controls a driving state of the gear rotation unit. The engine rotation information is the engine speed,
The rotation state control unit controls the drive state of the gear rotation means so that the flow path area is reduced below a maximum value in a state where the rotation speed of the engine is less than a predetermined rotation speed, and 11. The intake sound adjusting device according to claim 10, wherein a driving state of the gear rotating means is controlled so that the flow passage area becomes a maximum value in a state where the rotational speed is equal to or higher than a predetermined rotational speed.   The intake gear adjusting device according to claim 10 or 11, wherein the gear has teeth in a part in a circumferential direction.   The intake sound adjusting device according to any one of claims 3 to 12, comprising a plurality of the flow path area changing means.   14. The flow path area changing portion is formed by a plate-like member, and is supported so as to be rotatable about an axis that intersects the length direction of the communication pipe with respect to the communication pipe. The intake sound adjustment device described in any one of them.   15. The intake sound adjusting device according to claim 14, wherein the flow path area changing portion includes a shape changing portion whose length from the center of gravity to the edge changes when viewed from the axial direction of the communication pipe.   16. The intake sound adjusting device according to claim 15, wherein the shape changing portion is formed so that the flow path area changing portion is elliptical when viewed from the axial direction of the communication pipe.   The intake sound adjusting device according to any one of claims 3 to 16, wherein the flow path area changing portion is arranged on the outside air side of the elastic body.   The convex part which contacts the said flow-path area change part in the state in which the said flow-path area is the minimum value is formed in the internal peripheral surface of the said communicating pipe, The any one of Claim 3 to 16 characterized by the above-mentioned. The intake sound adjustment device described in 1.   The intake sound adjusting device according to claim 18, wherein the convex portion is a step of the inner peripheral surface formed by changing a thickness of the communication pipe.   The communication pipe is composed of a first series pipe configuration part communicating with the intake passage, and a second series pipe construction part arranged on the outside air side with respect to the first series pipe construction part. The intake sound adjusting device according to any one of claims 1 to 19.   21. The intake sound adjusting device according to claim 1, wherein a cross-sectional area of the second communication pipe component is larger than a cross-sectional area of the first continuous pipe component. .   The intake sound adjustment device according to any one of claims 1 to 21, wherein a length of the second communication pipe component is made different from a length of the first continuous pipe component.   The intake sound according to any one of claims 1 to 22, further comprising a support member that connects a part disposed in an engine room in which the engine is disposed and the flow path area changing unit. Adjusting device.

Images