KR102633965B1 - Sound generator for vehicle - Google Patents

Abstract

The present invention includes a resonator chamber having a structure that can be contracted or expanded in the longitudinal direction; A membrane mounted on the front opening of the resonator chamber; A cover mounted on the rear end opening of the resonator chamber; A connecting pipe connected between the cover and the engine intake system; A magnet mounted on the inner surface of the cover; A coil installed in the front end of the resonator chamber; and a sound controller that applies current to the coil. The aim is to provide an active sound generator for a vehicle, characterized in that it includes a.

Description

Vehicle sound generator {SOUND GENERATOR FOR VEHICLE}

The present invention relates to a sound generator for a vehicle, and more specifically, to an active sound generator for a vehicle that enables frequency tuning of engine sounds using a resonator and a membrane.

In the past, technology was mainly used to reduce engine noise from entering the interior to ensure quiet driving, but recently, sound has been amplified in various ways to create dynamic and sporty interior driving sounds.

The method of amplifying the sound can be broadly classified into three types: a membrane sound generator method, a method using an electric sound generator, and a method using an active sound generator.

The membrane sound generator method mounts a membrane on the dash panel (a partition member that separates the engine room and the interior), connects a pipe between the engine intake side and the membrane, and transmits the engine discharge sound directly into the interior through the membrane. As a method, it has the advantage of delivering the most natural tone by delivering the engine discharge sound directly into the room, but it has the disadvantage of not being able to tune the engine discharge sound to the desired frequency and thus not being able to realize the desired sound.

The electric sound generator uses a separate actuator to excite the dash panel, and the sound according to the excitation is transmitted into the room. It has the advantage of being able to tune to a desired frequency band, but rattle noise due to directly exciting the dash panel is generated. There are problems such as a decrease in the durability of the dash panel.

The active sound generator method is a method of arbitrarily generating sounds such as engine noise from an indoor speaker. It has the advantage of being able to tune to a desired frequency band, but it is difficult to experience the sound with the body because there is no vibration such as excitation, and the sound is natural. It has the disadvantage of giving an artificial sensibility rather than a tone, which creates a sense of heterogeneity.

The present invention was developed in consideration of the above points, and adopts a membrane sound generator method that can realize the most natural tone, but allows the engine discharge sound to be tuned to the desired frequency using a resonator, etc. to achieve the desired sound. The purpose is to provide an active sound generator for vehicles.

In order to achieve the above object, the present invention includes: a resonator chamber having a structure that can be contracted or expanded in the longitudinal direction; A membrane mounted on the front opening of the resonator chamber; A cover mounted on the rear end opening of the resonator chamber; A connecting pipe connected between the cover and the engine intake system; A magnet mounted on the inner surface of the cover; A coil installed in the front end of the resonator chamber; and a sound controller that applies current to the coil. It provides an active sound generator for a vehicle, characterized in that it includes a.

Preferably, the resonator chamber includes: a hollow chamber mounted on the dash panel; A bellows tube whose front end is connected to the hollow chamber and whose rear end is connected to the cover; It is characterized by being composed of.

In addition, a coil fastening groove into which a coil is inserted and fastened is formed on the inner surface of the hollow chamber.

In addition, a membrane is mounted on the front opening of the hollow chamber and is arranged in a sound wave transmission hole formed in the dash panel.

In addition, the inner surface of the cover is characterized by a magnetic fastening groove into which a magnet is inserted and fastened.

As an embodiment of the present invention, the connecting pipe is made of rubber and is connected between the cover and the engine intake system while having a predetermined deflection amount.

In another embodiment of the present invention, the connecting pipe is a metal pipe, and a slide groove having a length greater than the thickness of the cover is formed at the front end connected to the cover.

Preferably, the inner diameter portion of the cover is inserted into the slide groove of the connection pipe so that the cover moves along the length section of the slide groove when the resonator chamber expands or contracts.

The sound generator of the present invention further includes an engine ECU that transmits an engine RPM signal to the sound controller.

Preferably, the sound controller is configured to variably control the voltage applied to the coil according to the engine RPM so as to amplify the sound pressure of the engine frequency that varies depending on the engine RPM.

Through the means for solving the above problems, the present invention provides the following effects.

First, the sound generator of the present invention, unlike the existing membrane sound generator method, can implement a desired sound by tuning the engine discharge sound to a desired frequency using a resonator or the like.

Second, the sound generator of the present invention, unlike existing electric sound generators and active sound generators that produce artificial sounds, adopts a membrane method, so it can not only implement the engine sound in the most natural tone, but also produce sound in the desired frequency band. You can tune it with .

1 is an exploded perspective view showing a sound generator for a vehicle according to the present invention;
Figure 2 is an external perspective view showing the mounting state of the vehicle sound generator according to the present invention;
3 is a cross-sectional view showing a sound generator for a vehicle according to an embodiment of the present invention;
4 is a cross-sectional view showing a sound generator for a vehicle according to another embodiment of the present invention;
5A and 5B are diagrams showing the operating state of the vehicle sound generator according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The attached FIGS. 1 and 2 are external perspective views showing the mounted state of the vehicle sound generator according to the present invention, and FIG. 3 is a cross-sectional view showing the vehicle sound generator according to an embodiment of the present invention, where reference numerals refer to each figure. 10 indicates the resonator chamber.

The resonator chamber 10 is provided in a structure that can be contracted or expanded in the longitudinal direction.

Preferably, the resonator chamber 10 is composed of a hollow chamber 12 fixedly mounted on the dash panel 100, and a bellows pipe 14 that is fastened to the hollow chamber 12 to be able to expand or contract.

Accordingly, the total internal volume of the resonator chamber 10 decreases when the bellows tube 14 is contracted and increases when the bellows tube 14 expands.

At this time, a membrane 20 is mounted on the front opening of the resonator chamber 10, and a cover 30 having a hole is mounted on the rear opening of the resonator chamber 10.

More specifically, a membrane 20 is mounted on the front opening of the hollow chamber 12 of the resonator chamber 10, and a cover 30 is installed on the rear opening of the bellows pipe 14 of the resonator chamber 10. ) is installed.

In addition, when the front end of the hollow chamber 12 is mounted on the dash panel 100, the membrane 20 mounted on the front opening of the hollow chamber 12 is connected to the sound wave transmission hole 102 formed in the dash panel 100. It is in a state of being arranged in .

For reference, the membrane 20 is a thin plate that is also applied to general speakers, and serves to transmit sound waves to the outside while vibrating due to the sound pressure difference.

In particular, a connection pipe 40 is connected between the cover 30 and the engine intake system (eg, intake pipe).

According to one embodiment of the present invention, as shown in FIG. 3, the connecting pipe 40 is adopted as a pipe made of rubber that can be expanded or contracted, and at the same time has a predetermined amount of deflection and is connected between the cover 30 and the engine intake system. It is desirable to do so.

Accordingly, when the bellows pipe 14 expands or contracts, the cover 30 connecting the bellows pipe 14 and the connection pipe 40 also moves easily in the direction of expansion or contraction together with the bellows pipe 14. It becomes possible.

On the other hand, when the connecting pipe 40 is made of a metal pipe, unlike the rubber material, it does not expand in the longitudinal direction, so when the bellows pipe 14 expands or contracts, the cover 40 moves in the expansion or contraction direction together. Therefore, expansion or contraction of the bellows pipe 14 may eventually become impossible.

According to another embodiment of the present invention to solve this problem, as shown in FIG. 4, when the connection pipe 40 is made of a metal material, a cover ( A slide groove 42 having a length greater than the thickness of 40 is formed.

Accordingly, by inserting the inner diameter of the cover 40 into the slide groove 42 of the connection pipe 40, the cover 40 slides when the bellows pipe 14 of the resonator chamber 10 expands or contracts. Since it moves along the length section of the groove 42, expansion or contraction of the bellows pipe 14 can be guaranteed.

Typically, a resonator consists of a volume body with a specific capacity, like a plastic bottle, and a neck formed at the entrance of this volume body, and is mainly used to reduce sound in a specific frequency band using the resonance effect of sound. , the resonator frequency band is determined depending on the capacity of the volume body and the neck diameter and length.

For reference, a high sound pressure (dB) of a specific frequency is generated inside the resonator, and when a membrane is mounted on one side of the resonator, a sound amplification effect such as sound waves in the corresponding frequency band are intensively transmitted to the outside through the membrane is achieved. You can get it.

Therefore, the resonator chamber 10 consisting of the hollow chamber 12 and the bellows tube 14 functions as a resonator, and the membrane 20 mounted on the front end of the hollow chamber 12 generates sound waves in a specific frequency band. It serves to amplify sound so that it can be transmitted to the outside.

Accordingly, through the connection pipe 40, the engine sound passes through the bellows pipe 14 and the hollow chamber 12, which serve as a resonator, and acts on the membrane 20, thereby preventing the engine sound from entering the room through the membrane 20. It can be delivered.

Meanwhile, a coil fastening groove 13 into which the coil 50 is inserted and fastened is formed on the inner surface of the hollow chamber 12 constituting the resonator chamber 10.

Accordingly, the coil 50 wound in a circle several to dozens of times or more can be inserted and fastened into the coil fastening groove 13.

At this time, a sound controller 60 for applying current and voltage is electrically connected to the coil 50.

Preferably, the sound controller 60 is connected to an engine ECU 80 that transmits an engine RPM signal, so that the sound controller 60 receives the engine RPM signal of the engine ECU 80 and receives the received engine RPM signal. The voltage applied to the coil 50 is variably controlled according to the engine RPM to amplify the sound pressure of the engine frequency that varies depending on the engine RPM.

In addition, a magnetic fastening groove 32 is formed on the inner surface of the cover 30 into which the magnet 70 is inserted and fastened, and a permanent magnet 70 provided in a ring shape is inserted and fastened into this magnetic fastening groove 32. .

Accordingly, the magnet 70 exerts a repulsive force to move away from the coil 50 or an attractive force to stick to the coil 50, depending on the direction of the current applied to the coil 50.

Here, the operating flow of the sound generator of the present invention configured as described above is as follows.

The attached FIGS. 5A and 5B show the operating state of the vehicle sound generator according to the present invention.

First, when the engine ECU 80 transmits an engine RPM signal to the sound controller 60, the sound controller 60 controls the engine RPM, taking into account that the engine C2 component frequency varies depending on the engine RPM, as shown in Table 1 below. Accordingly, the voltage applied to the coil 50 is varied.

For reference, the engine C2 component frequency is expressed by symbolizing the vibration component as C2 when the basic vibration frequency of the engine is expanded to twice the crankshaft rotation speed. For any n-cylinder engine, the C2 component frequency is expressed as the crankshaft frequency. It can be expressed as a vibration component with a frequency of n/2 of the shaft rotation number.

For example, if the C2 frequency is 90Hz, which is lower than the standard value at 2700 RPM of the engine, the sound controller 60 applies the current direction to the coil 50 in one direction, as shown in FIG. 5A, so that the coil 50 At the same time as the magnetic field is generated, the front and rear ends of the coil 50 become N-pole and S-pole, respectively, thereby exerting a repulsive force to push the magnet 70 having the S-pole and N-pole arrangement.

Accordingly, the cover 30 in which the magnet 70 is installed moves backwards and the bellows pipe 14 connected to the cover 30 expands, thereby increasing the volume in the resonator chamber 10, thereby causing the connection pipe ( The engine sound flowing into the resonator chamber 10 through 40) can be amplified.

Therefore, as the volume of the resonator chamber 10 is increased as described above, the engine sound low frequency (for example, the C2 component frequency of 90 Hz at engine 2700 RPM) flowing into the resonator chamber 10 through the connection pipe 40 is generated by the resonator. By going through tuning amplified within the chamber 10 and acting on the membrane 20, the tuned engine sound can be transmitted to the room through the membrane 20.

On the other hand, if the C2 frequency at 6030 RPM of the engine is 201 Hz, which is higher than the standard value, as shown in FIG. 5b, the sound controller 60 applies the direction of the current applied to the coil 50 in the other direction, so that the coil 50 At the same time as the magnetic field is generated, the front and rear ends of the coil 50 become S-pole and N-pole, respectively, thereby exerting an attractive force to attract the magnet 70 having the S-pole and N-pole arrangement.

Accordingly, the cover 30 in which the magnet 70 is installed moves forward, and at the same time, the bellows pipe 14 connected to the cover 30 contracts, so that the volume in the resonator chamber 10 is reduced to a certain level.

Therefore, since the engine sound flowing into the resonator chamber 10 through the connection pipe 40 as described above has a high frequency above a certain level (for example, the C2 component frequency of 201 Hz at the engine 6030 RPM), the volume of the resonator chamber 10 Even if reduced to a certain level, the engine sound is amplified within the resonator chamber 10 and acts on the membrane 20 through tuning, so that the tuned engine sound can be transmitted to the room through the membrane 20.

In this way, by tuning the engine sound frequency to a desired level and delivering it indoors, the engine sound can be realized in the most natural tone and delivered indoors.

10: Resonator chamber
12: hollow chamber
13: Coil fastening groove
14: Bellows pipe
20: membrane
30: cover
32: Magnet fastening groove
40: connection pipe
42: Slide groove
50: coil
60: sound controller
70: magnet
80: Engine ECU
100: Dash panel
102: Sound wave transmission hole

Claims (10)

A resonator chamber having a structure that can be contracted or expanded in the longitudinal direction;
A membrane mounted on the front opening of the resonator chamber;
A cover mounted on the rear end opening of the resonator chamber;
A connecting pipe connected between the cover and the engine intake system;
A magnet mounted on the inner surface of the cover;
A coil installed in the front end of the resonator chamber;
a sound controller that applies current to the coil;
It is composed including,
A sound generator for a vehicle, characterized in that a magnetic fastening groove into which the magnet is inserted and fastened is formed on the inner surface of the cover.
In claim 1,
The resonator chamber:
a hollow chamber mounted on the dash panel;
A bellows tube whose front end is connected to the hollow chamber and whose rear end is connected to the cover;
A sound generator for a vehicle, characterized in that it consists of.
In claim 2,
A sound generator for a vehicle, characterized in that a coil fastening groove into which a coil is inserted and fastened is formed on the inner surface of the hollow chamber.
In claim 2,
A sound generator for a vehicle, wherein a membrane is mounted on the front opening of the hollow chamber and arranged in a sound wave transmission hole formed in the dash panel.
delete In claim 1,
The sound generator for a vehicle, wherein the connection pipe is made of rubber and is connected between the cover and the engine intake system while having a predetermined deflection amount.
In claim 1,
A sound generator for a vehicle, wherein the connecting pipe is a metal pipe, and a slide groove having a length greater than the thickness of the cover is formed at the front end connected to the cover.
In claim 7,
A sound generator for a vehicle in which the inner diameter of the cover is inserted into the slide groove of the connection pipe so that the cover moves along the length section of the slide groove when the resonator chamber expands or contracts.
In claim 1,
A sound generator for a vehicle, further comprising an engine ECU that transmits an engine RPM signal to the sound controller.
In claim 9,
A sound generator for a vehicle, wherein the sound controller is configured to variably control the voltage applied to the coil according to the engine RPM so as to amplify the sound pressure of the engine frequency that varies depending on the engine RPM.

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