JP2006273105A - Engine sound introduction structure of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine sound introduction structure of a vehicle for effectively introducing a specific frequency component. <P>SOLUTION: This engine sound introduction structure of a vehicle comprises a vibration element 225 excited by vibrations derived from an engine 210 of the vehicle, a vibration face 310 arranged in a compartment 100 of the vehicle and vibratably supported independent from a vehicle body 100, and a vibration transmission part 320 connected with the vibration element 225 and the vibration face 310, and arranged to penetrate through a body panel part 111 constituting a part of the compartment 110. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an engine sound introduction structure that introduces engine vibration of a vehicle engine, engine intake sound, engine exhaust sound, and the like into a vehicle interior.

In order to respond to user preferences in passenger cars and other vehicles, the intake sound generated by the intake system, etc., where the engine draws in outside air, is actively introduced into the passenger compartment where the passengers live, giving it a sense of sportiness and high performance. It is known to produce.
For example, it is known that a pipe portion branched from a part of an intake duct connected to the intake side of the engine is provided, and the other end portion is connected to a partition wall (bulk head) between the engine room and the passenger compartment. (For example, Patent Document 1).
JP 2004-218458 A

However, while the engine intake noise and the vibration sound resulting from the explosion in the cylinder include a wide range of frequency components, the effective frequency band for production in the passenger compartment is limited to a specific frequency, for example, near 250 Hz. Therefore, when the sound generated by the intake duct or the like is introduced as it is into the vehicle compartment as in the above-described prior art, an unnecessary frequency component may be included to give the user an impression of mere noise.
In view of the above-described problems, an object of the present invention is to provide a vehicle engine sound introduction structure that effectively introduces a specific frequency component.

The present invention solves the above-described problems by the following means.
According to a first aspect of the present invention, there is provided a vibrating body that is vibrated by vibration caused by an engine of a vehicle, a vibrating surface portion that is disposed in a vehicle interior of the vehicle and is supported so as to be able to vibrate independently of a vehicle body, and the vibrating body. And an engine sound introduction structure for a vehicle including a vibration transmitting portion that is connected to each of the vibration surface portions and is disposed through a body panel portion that constitutes a part of the passenger compartment.

According to a second aspect of the present invention, in the engine sound introduction structure for a vehicle according to the first aspect, the vibration transmitting portion transmits the vibration of the vibrating body to the vibration surface portion by solid propagation. Sound introduction structure.
According to a third aspect of the present invention, in the vehicle engine sound introduction structure according to the first or second aspect, the connecting portion to which the vibration transmitting portion of the vibrating body is connected is substantially equal to the natural frequency of the vibration surface portion. An engine sound introduction structure for a vehicle having the same natural frequency.
According to a fourth aspect of the present invention, in the engine sound introduction structure for a vehicle according to any one of the first to third aspects, the vibration transmitting portion includes at least the connection portion and the vibration surface portion of the vibrating body. An engine sound introduction structure for a vehicle characterized by having substantially the same natural frequency as that of one.
According to a fifth aspect of the present invention, in the engine sound introduction structure for a vehicle according to any one of the first to fourth aspects, the vibration transmitting portion is an inner peripheral edge portion of an opening formed in the body panel portion. An engine sound introduction structure for a vehicle, which is supported by the body panel portion via an elastic member provided in the vehicle.

According to the present invention, the following effects can be achieved.
(1) By transmitting the vibration of the vibrating body to the vibrating surface portion through the vibration transmitting portion by solid propagation and exciting the vibrating surface portion, the component near the natural frequency of the vibrating surface portion becomes a component in another frequency band. It is relatively amplified. And the radiated sound which generate | occur | produces by the vibration of a vibration surface part carries out acoustic propagation in a vehicle interior, and can introduce the engine sound of a specific frequency component into a vehicle interior effectively.
(2) Since the vibration transmission unit transmits the vibration of the vibrating body to the vibration surface part by solid propagation, the vibration transmission unit is necessary for the arrangement of the vibration transmission unit as compared with the case where acoustic transmission is performed inside using a pipe or the like. Space can be reduced and the structure can be simplified.
(3) Since the connection portion to which the vibration transmission portion of the vibrating body is connected and the vibration surface portion have substantially the same natural frequency, the vibration surface portion resonates due to the propagation of vibration from the vibration body, The frequency component can be emphasized.
(4) Since the natural frequency of the vibration transmitting portion is substantially the same as that of at least one of the connecting portion and the vibrating surface portion of the vibrating body, resonance occurs between them, and a specific frequency component can be further emphasized. it can.
(5) Since the vibration transmitting portion is supported by the body panel portion via the elastic member, the vibration characteristics of the body panel portion do not affect the function of the engine sound introduction structure.
Further, even when the vibrating body is displaced with respect to the vehicle body due to deformation of the engine mount or the like, for example, this displacement can be absorbed by the deformation of the elastic member.

  The object of the present invention is to provide a vehicle engine sound introduction structure that effectively introduces a specific frequency component, and the vibration generated by the intake chamber is provided in the cabin by solid propagation through the stay. It was realized by propagating solid to the diaphragm and propagating as a radiated sound from this diaphragm into the car.

A first embodiment of an engine sound introduction structure to which the present invention is applied will be described below with reference to the drawings.
FIGS. 1 and 2 are schematic views showing the configuration of the engine sound introduction structure of the first embodiment, and are views showing the vehicle as viewed from the side and above, respectively. FIG. 3 is an external perspective view of the engine. FIG. 4 is an enlarged view of a portion IV in FIG.

The vehicle 1 is, for example, a sedan type or station wagon type passenger car, and includes a cabin (vehicle compartment) 110, an engine room 150, a power train 200, and an engine sound introduction unit 300.
The cabin 110 is a room in which a passenger is accommodated, and is formed by a toe board 111, a bulkhead 112, a floor panel 113, a floor tunnel 114, and the like. In the cabin 110, a dashboard 115, a steering shaft 116, and a steering support beam 117 are formed. Etc.

The toe board (body panel portion) 111 is provided at the front end portion of the cabin 110, and is a partition wall that partitions the cabin 110 and the engine room 150, and is provided at a position corresponding to the feet of the front seat passenger and the upper portion thereof. Yes. In addition, a sound insulating material (insulator) 111 a is partially attached to the surface of the toe board 111 on the vehicle inner side.
A portion of the toe board 111 is formed with an opening 111b through which a stay 320 of an engine sound introduction unit 300 described later is inserted (see FIG. 4). The opening 111b is disposed in an area inside the dashboard 115 and below the steering support beam 117 when viewed from the cabin 110 inside. Further, the insulator 111a described above is arranged so as to avoid the peripheral portion of the opening 111b.

The bulkhead 112 is a tray-like member that protrudes from the upper portion of the toe board 111 toward the engine room 150 and opens upward, and includes a space portion that accommodates a wiper motor (not shown) therein.
The floor panel 113 is a floor surface portion of the cabin 110, and is continuously formed extending from the lower end portion of the toe board 111 to the rear side of the vehicle.
The floor tunnel 114 is formed such that a center portion of the floor panel 113 in the vehicle width direction is recessed in the vehicle interior and extends in the vehicle front-rear direction, and will be described later in a space portion formed below the floor tunnel 114. A rear portion of the transmission 230, a propeller shaft extending to the rear side of the vehicle, an exhaust pipe, and the like are accommodated.
The toe board 111, the bulkhead 112, the floor panel 113, and the floor tunnel 114 described above are formed by pressing a steel plate, and each constitutes a part of the vehicle body monocoque.

The dashboard 115 is provided on the inner surface of the toe board 111 and accommodates an air conditioner, an instrument, audio equipment, an SRS passenger seat airbag, etc. (not shown). It is formed along the lower end portion of the windshield, and the lower end portion side opens to the vehicle interior side.
The steering shaft 116 is a rotating member that connects a steering wheel and a steering gear box (not shown), and a part of the steering shaft 116 is disposed in the dashboard 115 described above.
The steering support beam 117 is a beam-like structural member provided in the dashboard 115 and provided in the vehicle width direction, and includes a steering column (not shown) that houses the steering shaft 116 and other constituent members (not shown). It is something to support.

  The engine room 150 is provided on the front side of the vehicle with respect to the cabin 110 and includes a space in which the power train 200 is accommodated.

The power train 200 includes an engine body 210, an intake system 220, and a transmission 230.
The engine main body 210 is, for example, a 4-stroke gasoline engine, for example, a horizontally opposed four-cylinder naturally aspirated engine. However, the type of the engine is not limited to this, and an explosion or intake pulsation in the combustion chamber occurs during operation. Any device that generates periodic vibrations due to exhaust pulsation, other mechanical vibrations, or the like may be used.

  The intake system 220 includes an intake duct 221, a resonator 222, an air cleaner case 223, a side branch 224, a chamber 225, a throttle body 226, and an intake manifold 227.

The intake duct 221 is provided with an intake port that is open to the outside at one end thereof, and the other end is connected to the air cleaner case 223 and communicates with the inside thereof.
The resonator 222 is a container-like member connected to an opening (not shown) formed in the side wall portion of the intake duct 221, and uses a pressure fluctuation in the intake duct 221 caused by intake pulsation or the like as a vibration source. It functions as a resonance chamber and is used for tuning the intake sound.
The air cleaner case 223 is formed in a container shape, and accommodates therein an air cleaner element (not shown) that filters fine dust and the like contained in the intake air.
The branch pipe 224 is provided by branching from the intake pipe between the air cleaner case 223 and the chamber 225, and the pipe is closed at the tip, and utilizes the air column resonance generated inside the branch pipe 224. It is used for tuning the intake sound.
The chamber (vibrating body) 225 is a resonance chamber that is provided in the middle of the intake pipe line between the air cleaner case 223 and the throttle body 226 and is formed in a container shape by a material such as resin, for example. The output of the engine main body 210 is improved by exhibiting the supply effect. The chamber 225 is disposed on the upper portion of the engine body 210 and is rigidly fixed to the engine body 210 by a stay (not shown). The chamber 225 is provided with a lower surface portion 225a as a connecting portion formed in a flat shape and disposed substantially horizontally, and on the vehicle rear side, an inclined surface portion is provided with an upper end portion provided behind the lower end portion and is inclined. 225b is formed.
The throttle body 226 is provided between the chamber 225 and the intake manifold 227, and accommodates a throttle valve that limits the intake air amount of the engine 210 in accordance with an operation of an operation unit such as a throttle pedal (not shown).
The intake manifold 227 is connected to the downstream side of the throttle body 226 and includes branch pipes respectively connected to intake ports of cylinders (not shown) of the engine 210.

  The transmission 230 is coupled to a rigid side by a plurality of bolts (not shown) on the rear side of the engine body 210, and a transmission unit that decelerates or increases the rotational output of the engine body 210, and a transfer unit that distributes the output of the transmission unit to the front and rear wheels. The front differential part for transmitting the rotational output of the transfer part to the drive shafts of the left and right front wheels is accommodated in the same case.

The engine sound introduction section 300 includes a diaphragm (vibration surface section) 310 and a stay (vibration transmission section) 320.
The vibration plate 310 is formed in a rectangular flat plate shape using, for example, a steel plate, and is disposed in the cabin 110. The diaphragm 310 is disposed substantially parallel to the surface of the toe board 111 on the vehicle inner side with a predetermined interval.

The stay 320 is formed in a columnar shape by, for example, a steel round bar, and is provided to extend in the front-rear direction of the vehicle.
The front end portion of the stay 320 is fixed to the lower surface portion 225 a of the chamber 225, and the rear end portion is fixed to the substantially central portion of the surface portion of the diaphragm 310 that faces the toe board 111.
As shown in FIG. 4, the stay 320 includes a front portion 320a extending from the lower surface 225a of the chamber 225 to the rear side of the vehicle, an intermediate portion 320b extending upward from the rear end portion of the front portion 320a, The rear portion 320c extends from the upper end portion of the portion 320b to the rear side of the vehicle, and is formed in a crank shape as a whole.
In addition, the connection part of the stay 320, the chamber 225, and the diaphragm 310 is couple | bonded with a rigid, for example by screw coupling, welding, etc., and the solid propagation of a vibration is possible.

The stay 320 has a rear portion 320 c inserted into an opening 111 b formed in the toe board 111 and is disposed through the toe board 111.
The inner diameter of the opening 111 b is formed larger than the outer diameter of the stay 320. In the opening 111b, an annular grommet 111c formed of an elastic material such as rubber is fixed to the inner peripheral edge portion thereof, and the stay 320 is inserted into the center portion thereof so that a so-called floating state is achieved. Supported by the toe board 111. Thereby, the diaphragm 310 and the stay 320 are supported so as to be able to vibrate independently of the vehicle body 100.

Next, the vibration characteristics of the chamber 225, the diaphragm 310, and the stay 320 and the mechanism for introducing engine sound will be described.
The chamber 225 is designed in terms of structure, shape, surface portion rigidity, and the like so that the natural frequency of the lower surface portion 225a to which the stay 320 is connected is, for example, about 250 Hz.
Note that such a frequency is set in consideration of, for example, a rendering effect that appeals the driver to the high-performance feeling of the vehicle, and may be another frequency.
When the chamber 225 is vibrated by the intake pulsation or the like during the operation of the engine body 210, the lower surface portion 225 a exhibits a vibration mode in the vicinity of about 250 Hz, and this vibration is propagated to the stay 320.

The material, shape, and the like of the diaphragm 310 and the stay 320 are designed so that the natural frequency thereof is, for example, about 250 Hz. These natural frequencies can be measured, for example, by suspending a single member to be measured with a rubber string or the like and applying vibration by hammering.
The vibration generated in the lower surface 225a of the chamber 225 and having a peak in the vicinity of about 250 Hz vibrates the stay 320, and the stay 320 transmits this vibration to the diaphragm 320 by solid propagation. At this time, since both the stay 320 and the diaphragm 310 have a natural frequency in the vicinity of about 250 Hz, resonance occurs in each member, and the frequency band component in the vicinity of about 250 Hz is further emphasized.
The diaphragm 310 generates a radiated sound due to the vibration, and the radiated sound is propagated from the lower opening of the dashboard 115 to the passenger side by acoustic propagation to the air in the cabin 110, and the engine sound is transmitted. Introduction is done.

As described above, according to this embodiment, the following effects can be obtained.
(1) The vibration generated in the lower surface portion 225a of the chamber 225 is transmitted to the diaphragm 310 via the stay 320 by solid propagation, and the diaphragm 310 is vibrated, so that the natural frequency of the diaphragm 310 is reduced. Components near 250 Hz are amplified relative to other frequency band components. A specific sound component in the vicinity of the natural frequency of the vibration plate 310 can be effectively introduced into the cabin 110 by radiating sound generated from the surface of the vibration plate 310 by this vibration. .
(2) Since the stay 320 transmits the vibration of the chamber 225 to the diaphragm 310 by solid propagation, the space required for the arrangement can be reduced as compared with the case where acoustic propagation is performed using, for example, a pipe line. The structure can also be simplified.
(3) Since the lower surface portion 225a of the chamber 225 and the diaphragm 310 both have substantially the same natural frequency in the vicinity of about 250 Hz, the diaphragm 310 resonates due to vibration transmitted from the chamber 225, and a frequency in the vicinity of about 250 Hz. Ingredients can be emphasized.
(4) Since the natural frequency of the stay 320 is set in the vicinity of about 250 Hz, which is substantially the same as that of the lower surface portion 225a of the chamber 225 and the diaphragm 310, resonance also occurs in the stay 320, thereby enhancing the frequency in the vicinity of about 250 Hz. can do.
(5) Since the stay 320 is floating mounted on the toe board 111 via the grommet 111c formed of an elastic material, the function of the engine sound introducing unit 300 is not affected by the vibration characteristics of the toe board 111.
Even when the chamber 225 is displaced with respect to the vehicle body 100 due to elastic deformation of the engine mount, the grommet 111c is twisted to displace the stay 320 and the diaphragm 310, thereby absorbing the displacement of the chamber 225. can do.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes can be made, and these are also within the equivalent scope of the present invention.
(1) In the above-described embodiment, the chamber is used as the vibrator. However, the present invention is not limited to this. For example, other parts of the intake system such as a resonator, an air cleaner case, a side branch, a surge tank, an engine block, and a transmission Any member that vibrates due to the operation of the engine such as a case can be used.
In particular, according to the present invention, the present invention is not limited to an intake system or the like that is relatively easy to tune to emphasize a component in a specific frequency band, but may be a case where an engine main body or the like including a component in a wide frequency band is used as a vibrating body. However, it is possible to effectively introduce a component in a specific frequency band by tuning the frequency characteristics of the vibration surface portion and the vibration transmission portion.
The vibration caused by the engine has a fundamental wave component periodically generated every rotation of the crankshaft and a higher order component having a frequency that is a multiple of the fundamental wave component, and these frequencies are proportional to the engine speed. However, even if the engine speed changes, if the component of any order includes a specific frequency band, the above-described effects can be obtained using this as the excitation source. .
(2) Although the embodiment is configured to support the stay, which is a vibration transmission unit, only at the body panel unit, the vibration transmission unit may be supported at a plurality of locations as necessary. In this case, it is preferable to use a floating mount via an elastic member at each support location. Further, the vibration surface portion may be supported by a floating mount.
(3) The structure, shape, material, and the like of the vibration surface portion and the vibration transmission portion are not limited to the above-described embodiments, and may be other configurations.
(4) Although the embodiment emphasizes a frequency band near 250 Hz, for example, such a frequency may be changed, and a plurality of engine sound introduction structures each having different frequency characteristics. May be used in combination.
(5) Although the toe board is used as the body panel portion in the embodiment, the present invention is not limited thereto, and other members such as a floor panel may be used.
(6) Although the embodiment absorbs the movement of the vibrating body due to the elastic deformation of the engine mount or the like by the deformation of the elastic member (grommet) that supports the vibration transmitting portion, the present invention is not limited to this. The part may be provided with a connecting part capable of solid propagation of vibration, such as a ball joint or a slide mechanism, and deformed in accordance with the displacement of the vibrating body, and may absorb the displacement of the vibrating body by the deformation.
(7) The engine in the embodiment is a 4-stroke 4-cylinder gasoline engine, but may be an engine using an alternative fuel such as CNG, methanol, hydrogen, or a diesel engine. Furthermore, the number and arrangement of cylinders are not limited to this, and may be a Wankel rotary engine or the like.

It is the schematic which shows the structure of Example 1 of the engine sound introduction structure to which this invention is applied, Comprising: It is a figure which shows the state seen from the side surface side of the vehicle. It is the schematic which shows the structure of the engine sound introduction structure of FIG. 1, Comprising: It is a figure which shows the state seen from the upper direction of the vehicle. It is an external appearance perspective view of the engine provided with the engine sound introduction structure of FIG. It is the IV section enlarged view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 110 Cabin 111 Toe board 111b Opening 111c Grommet 115 Dashboard 150 Engine room 210 Engine main body 220 Intake system 225 Chamber 300 Engine sound introduction part 310 Diaphragm 320 Stay

Claims (5)

A vibrator that is vibrated by vibration caused by a vehicle engine;
A vibration surface portion disposed in the vehicle interior of the vehicle and supported so as to be able to vibrate independently of the vehicle body;
A vehicle engine sound introduction structure comprising: a vibration transmitting portion that is connected to each of the vibrating body and the vibration surface portion and is disposed through a body panel portion that constitutes a part of the passenger compartment. The engine sound introduction structure for a vehicle according to claim 1,
The engine sound introduction structure for a vehicle, wherein the vibration transmission unit transmits the vibration of the vibrating body to the vibration surface unit by solid propagation. The engine sound introduction structure for a vehicle according to claim 1 or 2,
The engine sound introduction structure for a vehicle, wherein a connection portion to which the vibration transmission portion of the vibrating body is connected has a natural frequency substantially the same as a natural frequency of the vibration surface portion. In the vehicle engine sound introduction structure according to any one of claims 1 to 3,
The structure for introducing engine sound of a vehicle, wherein the vibration transmission unit has substantially the same natural frequency as at least one of the connection portion and the vibration surface portion of the vibrating body. The vehicle engine sound introduction structure according to any one of claims 1 to 4,
The structure for introducing engine noise of a vehicle, wherein the vibration transmitting portion is supported by the body panel portion through an elastic member provided at an inner peripheral edge portion of an opening formed in the body panel portion.

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