Intake noise amplification device of internal combustion engine

Abstract

To enlarge a frequency band for amplifying intake noise.SOLUTION: An intake noise amplification device includes: a vibrator 21 for vibrating by intake air pulsation from an intake passage 2; a first housing 22 arranged in a portion on an intake passage 2 side of a branch pipe 10 with respect to the vibrator 21; and a second housing 26 arranged in a portion on a vehicle interior R side of the branch pipe 10 with respect to the vibrator 21. The vibrator 21 is sandwiched between the first housing 22 and the second housing 26. One of the first housing 22 and the second housing 26 includes a grating plate 25 having gratings 25a and 25b dividing the vibrator 21 into a plurality of regions. The other of the first housing 22 and the second housing 26 includes a hole plate 29 having a plurality of small holes 29a whose areas are smaller than the minimum area of the region divided by the grating plate 25.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The technology disclosed herein belongs to the technical field of an intake noise amplification device for an internal combustion engine. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known a structure for transmitting intake noise generated in an intake passage of an internal combustion engine to an outside of the engine compartment, such as into the passenger compartment.

[0003] For example, Patent Document 1 discloses an intake sound introduction device including a branch passage branching from an intake passage of an internal combustion engine, an introduction pipe connected to the end of the branch passage on the passenger compartment side and communicating with the branch passage, a sound creator having a vibrator provided at the end of the introduction pipe on the passenger compartment side and vibrating due to intake pulsation of intake sound transmitted through the branch passage and the introduction pipe, and a casing surrounding the introduction pipe so as to form a space between the introduction pipe and the vibrator, and a transmission path communicating with the casing of the sound creator for transmitting vibrations of the vibrator into the passenger compartment.In Patent Document 1, vibrations of a specific frequency among the sound vibrations caused by the vibration of the vibrator as a sound source are amplified by air column resonance in the casing and transmitted into the passenger compartment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 06216527 Summary of the Invention [Problem to be solved by the invention]

[0005] The purpose of transmitting intake sound into the vehicle cabin is to create a sporty feel and improve the driver's mood, as well as to provide driving assistance by providing feedback to the driver's operations.Since the frequency of intake pulsation changes depending on the rotation speed of the internal combustion engine, it is necessary to amplify the intake sound over a wide range, from low frequencies to high frequencies, especially from the perspective of driving assistance.

[0006] The technology disclosed herein has been made in consideration of the above points, and its purpose is to expand the frequency band in which intake noise is amplified in an intake noise amplifier. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, a first aspect of the technology disclosed herein is directed to an intake sound amplification device for an internal combustion engine that is provided in a branch pipe that branches off from an intake passage of an internal combustion engine mounted on a vehicle and transmits intake sound to a vehicle interior. The device comprises: a plate-shaped vibrator that vibrates due to intake pulsation from the intake passage; a first housing that is arranged in a portion of the branch pipe that is closer to the intake passage than the vibrator; and a second housing that is arranged in a portion of the branch pipe that is closer to the vehicle interior than the vibrator. The vibrator is sandwiched between the first housing and the second housing, and one of the first housing and the second housing includes a lattice plate that has a lattice that divides the vibrator into a plurality of regions when viewed from a direction perpendicular to the surface of the vibrator. The other of the first housing and the second housing includes a hole plate that has a plurality of holes with an area smaller than the smallest area divided by the lattice plate when viewed from the direction perpendicular to the surface of the vibrator.

[0008] In the first aspect, intake pulsation, an intake noise with a frequency corresponding to the rotation speed of the internal combustion engine, is generated in the intake passage. The intake pulsation is transmitted to the vibrator by a branch pipe. The vibrator vibrates due to the intake pulsation. The portion of the vibrator defined by the lattice plate resonates with the intake pulsation in a relatively low frequency band, amplifying the low-frequency band intake noise. On the other hand, the portion of the vibrator located at the hole resonates with the intake pulsation in a relatively high frequency band, amplifying the high-frequency band intake noise. This allows the frequency band over which the intake noise is amplified to be expanded.

[0009] In a second aspect, in the first aspect, the grid plate is provided in the first housing, and the hole plate is provided in the second housing.

[0010] In the second embodiment, the partition area of the grid plate is larger than the area of the holes, and the grid plate is positioned relatively upstream, so that low-frequency sound waves act directly on the entire portion of the vibrating body partitioned by the grid plate, thereby efficiently amplifying low-frequency intake noise.

[0011] A third aspect is the first aspect, wherein the number of holes in the hole plate is greater than the number of compartments in the grid plate.

[0012] In the third aspect, even if the area of each hole is small, the intake noise in the high frequency band can be appropriately amplified by resonating through a plurality of holes.

[0013] In a fourth aspect, in the first aspect, the grid plate has a first partition having a relatively large area and a second partition having a relatively small area, and the area of the hole is smaller than the area of the second partition.

[0014] In the fourth aspect, the partition area of the second partition is intermediate between the partition area of the first partition and the area of the hole. Therefore, the second partition can be used to amplify intake noise in the mid-frequency band. This allows the frequency band in which intake noise is amplified to be expanded.

[0015] A fifth aspect is any one of the first to fourth aspects, wherein the vibrator is made of rubber.

[0016] In the fifth aspect, if the vibrating body is made of rubber, it is easy to vibrate only the area partitioned by the lattice plate or only the area where the holes are located. Also, by changing the hardness, the resonant frequency can be easily adjusted. This allows the frequency band in which intake noise is amplified to be expanded. [Effects of the Invention]

[0017] As described above, the technology disclosed herein can expand the frequency band in which intake noise is amplified. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic diagram of an intake system of an internal combustion engine having an intake sound amplification device according to this embodiment. [Figure 2] FIG. 2 is a plan view showing the branch pipe. [Figure 3] FIG. 3 is a cross-sectional perspective view taken along a plane corresponding to line III-III in FIG. [Figure 4] FIG. 4 is a front view of the intake sound amplifier from the upstream side of the intake passage. [Figure 5] FIG. 5 is a cross-sectional view taken along a plane corresponding to line VV in FIG. [Figure 6] FIG. 6 is a front view showing the region that resonates at low frequencies. [Figure 7] FIG. 7 is a front view showing the region that resonates at medium frequencies. [Figure 8] FIG. 8 is a front view showing the region that resonates at high frequencies. [Figure 9] FIG. 9 is a graph showing the relationship between the rotation speed of the internal combustion engine and the sound volume in this embodiment and in the conventional case. [Figure 10] FIG. 10 is a front view showing a first modification of the intake sound amplifier. [Figure 11] FIG. 11 is a front view showing a second modification of the intake sound amplifier. DETAILED DESCRIPTION OF THE INVENTION

[0019] Exemplary embodiments will now be described in detail with reference to the drawings.

[0020] (Overall structure of branch pipe) FIG. 1 shows a schematic diagram of an intake system of an internal combustion engine 1. The internal combustion engine 1 is disposed in an engine compartment ER of a vehicle V. An intake passage 2 for introducing intake air is connected to the internal combustion engine 1. The intake passage 2 includes an air cleaner 3. The intake air purified by the air cleaner 3 is introduced into the internal combustion engine 1.

[0021] A branch pipe 10 branches off from the intake passage 2 downstream of the air cleaner 3. The branch pipe 10 is a portion for introducing the intake pulsation of the intake sound into the vehicle interior R. The branch pipe 10 is arranged in the engine room ER together with the intake passage 2.

[0022] 2, the branch pipe 10 has an inlet pipe 11 connected to the intake passage 2, an outlet pipe 12 communicating with the interior of the vehicle compartment R, and an intake sound amplifier 20 located between the inlet pipe 11 and the outlet pipe 12 and amplifying the intake sound. A bracket 14 is provided at the position of the intake sound amplifier 20 to fix the branch pipe 10 to the vehicle body.

[0023] The inlet pipe 11 is connected to the upper part of the intake passage 2. This allows the intake air pulsation to be transmitted without allowing most of the intake air passing through the intake passage 2 to escape to the branch pipe 10. Even if the intake air flows into the branch passage 10, it is blocked by the intake sound amplifier 20, so the intake air passing through the intake passage 2 is not introduced directly into the passenger compartment R.

[0024] The outlet pipe 12 communicates with an area of the vehicle interior R on the driver's seat side.

[0025] (Intake sound amplifier) The intake sound amplifier 20 is a device for amplifying intake sound and transmitting it to the vehicle interior R. The intake sound amplifier 20 amplifies the intake sound by causing a vibrating body 21, which will be described later, to vibrate greatly through resonance. The intake sound amplifier 20 will be described below with reference to FIGS. 3 to 8.

[0026] 3, the intake sound amplifier 20 has a vibrator 21 that vibrates due to the intake pulsation of the intake sound, a first housing 22 arranged on the inlet pipe 11 side of the vibrator 21, and a second housing 26 arranged on the outlet pipe 12 side of the vibrator 21. The first housing 22 and the second housing 26 are fixed so as not to move relative to each other.

[0027] The vibrating body 21 is made of a disc-shaped rubber. The hardness and thickness of the vibrating body 21 are not particularly limited and are changed depending on the type of vehicle V. The outer diameter of the vibrating body 21 is larger than the outer diameter of a first main body portion 23 (described later) of the first housing 22 and the outer diameter of a second main body portion 27 (described later) of the second housing 26.

[0028] The first housing 22 has a first main body portion 23, a first flange portion 24 provided at the downstream end of the first main body portion 23, and a lattice plate 25 provided at the downstream end within the first main body portion 23. The first housing 22 is made of resin.

[0029] The first main body portion 23 has a tubular shape and is disposed within the downstream end portion of the inlet pipe 11.

[0030] The first flange portion 24 extends radially outward from the first main body portion 23 and expands over the entire circumferential direction. The first flange portion 24 has a protruding portion 24a that protrudes toward the downstream side. The protruding portion 24a extends continuously over the entire circumferential direction of the first flange portion 24. In other words, the protruding portion 24a has an annular shape when viewed from the axial direction of the first housing 22. A recessed portion 24b that is recessed toward the upstream side is provided in the center of the width direction of the protruding portion 24a. The recessed portion 24b extends continuously over the entire circumferential direction of the first flange portion 24 along the protruding portion 24a.

[0031] 4, the grid plate 25 has a pair of first grids 25a that extend straight in the radial direction and divide the first body portion 23 into four sections, and a second grid 25b that is annular and centered on the tube axis of the first body portion 23. The first grid 25a is integral with the first body portion 23. The second grid 25b is integral with the first grid 25a. The outer diameter of the second grid 25b is approximately one-third of the inner diameter of the first body portion 23.

[0032] The grid plate 25 has four quadrant-arc-shaped first partitions 25c located inside the first main body portion 23 and outside the second grid 25b. The grid plate 25 has four quadrant-arc-shaped second partitions 25d located inside the second grid 25b. The first partitions 25c are located radially outside the second partitions 25d. The first partitions 25c have a larger area than the second partitions 25d. The four first partitions 25c all have the same area. The four second partitions 25d all have the same area.

[0033] As shown in FIG. 5, the first main body portion 23, the first grating 25a, and the second grating 25b are embedded in the vibrating body 21. As shown in FIG.

[0034] 3, the second housing 26 has a second main body portion 27, a second flange portion 28 provided at the downstream end of the second main body portion 27, and a hole plate 29 provided at the downstream end within the second main body portion 27. The second housing 26 is made of resin.

[0035] The second main body portion 27 is tubular and is fixed to the upstream end of the outlet pipe 12. The bracket 14 described above is provided on the second main body portion 27.

[0036] The second flange portion 28 extends radially outward from the second main body portion 27 and expands circumferentially. The second flange portion 28 has a groove 28a with which the protrusion 24a of the first flange portion 24 engages. The groove 28a extends continuously over the entire circumferential direction of the second flange portion 28. In other words, the groove 28a has an annular shape when viewed in the axial direction of the second housing 26. A protrusion 28b that protrudes toward the upstream side is provided at the center of the width of the groove 28a. The protrusion 28b extends continuously over the entire circumferential direction of the second flange portion 28 along the groove 28a. The protrusion 28b engages with the recess 24b of the first flange portion 24.

[0037] The second flange portion 28 has a housing portion 28c that houses the vibrating body 21.

[0038] As shown in FIG. 4, the hole plate 29 has a plurality of small holes 29a with relatively small diameters and large holes 29b with relatively large diameters.

[0039] A plurality of small holes 29a are provided in an area corresponding to the first partitions 25c. The area of the small holes 29a is smaller than the area of the second partitions 25d. The arrangement pattern of the small holes 29a in each first partition 25c is rotationally symmetric about the tube axis of the first housing 22 when viewed from the tube axis direction of the first housing 22. The small holes 29a are not arranged at positions corresponding to the first lattice 25a and the second lattice 25b. Note that the arrangement pattern of the small holes 29a in each first partition 25c does not necessarily have to be rotationally symmetric about the tube axis of the first housing 22.

[0040] The large holes 29b are provided in regions corresponding to the second partitions 25d. Four large holes 29b are provided corresponding to the four second partitions 25d. The area of each large hole 29b is smaller than the area of each second partition 25d. The large holes 29b are not arranged in positions corresponding to the first lattice 25a and the second lattice 25b.

[0041] As shown in FIG. 5, the upstream surface of the perforated plate 29 is in close contact with the vibrating body 21 without biting into the vibrating body 21.

[0042] When the intake pulsation of the intake sound is transmitted from the inlet pipe 11, the vibrating body 21 vibrates. This causes sound to be generated from the vibration of the vibrating body 21. When the vibrating body 21 vibrates greatly due to resonance, the sound is amplified.

[0043] 6 to 8 show the parts of vibrating body 21 that resonate with intake pulsation in each frequency band. Fig. 6 shows the part that resonates with low-frequency intake pulsation, Fig. 7 shows the part that resonates with medium-frequency intake pulsation, and Fig. 8 shows the part that resonates with high-frequency intake pulsation. The low, medium, and high frequencies are the low, medium, and high frequencies when the frequency band to be amplified is divided into thirds.

[0044] As shown in Fig. 6, the portion of vibrating body 21 located in first partition section 25c (hereinafter referred to as the first portion) resonates with the low-frequency intake pulsation. Each of the four first portions of vibrating body 21 vibrates in resonance. The sound generated by the resonant vibration passes through small holes 29a and is transmitted to outlet pipe 12, and then into passenger compartment R.

[0045] As shown in Fig. 7, the portion of vibrating body 21 located in second partition section 25d (hereinafter referred to as the second portion) resonates with the intake pulsation of the medium frequency. Each of the four second portions of vibrating body 21 vibrates in resonance. The sound generated by the resonant vibration passes through large hole 29b and is transmitted to outlet pipe 12, and then to the interior of vehicle interior R.

[0046] As shown in Fig. 8, the portions of the vibrating body 21 located at the small holes 29a (hereinafter referred to as third portions) resonate with the high-frequency intake pulsation. Each of the third portions of the vibrating body 21 vibrates in resonance. The sound generated by the resonant vibration is transmitted to the outlet pipe 12 and then transmitted into the passenger compartment R.

[0047] In this way, the portions of vibrating body 21 that correspond to each frequency vibrate due to resonance, amplifying the intake sound. The partition area of second partition 25d is set to an area such that the resonance frequency of the second portion of vibrating body 21 is not an integer multiple of the resonance frequency of the first portion of vibrating body 21. In addition, the area of small hole 29a is set to an area such that the resonance frequency of the third portion of vibrating body 21 is not an integer multiple of the resonance frequencies of the first and second portions of vibrating body 21.

[0048] FIG. 9 shows the results of comparing the sound volume when using the intake sound amplifier 20 according to this embodiment with the sound volume when using a conventional intake sound amplifier. The horizontal axis represents the engine speed. Generally, the higher the engine speed, the higher the frequency of the intake pulsation of the intake sound. Both intake sound amplifiers amplify the intake sound at a frequency that corresponds to the engine speed. The arrows in the figure indicate areas where the intake sound amplification effect of the intake sound amplifier 20 according to this embodiment is significant.

[0049] As shown in Figure 9, when the intake sound amplifier 20 according to this embodiment is used, it can be seen that the volume is generally louder from the low rotation range to the high rotation range compared to the conventional intake sound amplifier. It can be seen that there are parts where the volume is significantly louder over a wide range from the low rotation range to the high rotation range. Therefore, the intake sound amplifier 20 according to this embodiment can expand the frequency band in which intake sound is amplified.

[0050] (Effects of the embodiment) As described above, in this embodiment, the vibrating body 21 is sandwiched between the first housing 22 and the second housing 26. The first housing 22 includes the lattice plate 25 having lattices 25a and 25b that divide the vibrating body 21 into multiple regions when viewed perpendicular to the surface of the vibrating body 21. The second housing 26 includes the hole plate 29 having multiple small holes 29a with an area smaller than the smallest area divided by the lattice plate 25 when viewed perpendicular to the surface of the vibrating body 21. The portion of the vibrating body 21 divided by the lattice plate 25 resonates with intake pulsations in a relatively low frequency band, amplifying the intake noise in the low frequency band. On the other hand, the portion of the vibrating body 21 located at the small holes 29a resonates with intake pulsations in a relatively high frequency band, amplifying the intake noise in the high frequency band. This allows the frequency band over which the intake noise is amplified to be expanded.

[0051] Furthermore, since the lattice plate 25 is positioned relatively upstream, sound waves in the low frequency band act directly on the entire portion of the vibrating body 21 partitioned by the lattice plate 25. This allows the intake sound in the low frequency band to be efficiently amplified.

[0052] In this embodiment, the number of small holes 29a in the hole plate 29 is greater than the number of compartments in the lattice plate 25. As a result, even if the area of each small hole 29a is small, the intake noise in the high frequency band can be appropriately amplified by resonating through the multiple small holes 29a.

[0053] In this embodiment, the grid plate 25 has a first partition 25c with a relatively large area and a second partition 25d with a relatively small area, and the area of the small holes 29a is smaller than the area of the second partition 25d. The area of the second partition 25d is intermediate between the area of the first partition 25c and the area of the small holes 29a. Therefore, the second partition 25d can be used to amplify intake noise in the mid-frequency band. This allows the frequency band in which intake noise is amplified to be expanded.

[0054] In this embodiment, the partition area of second partition 25d is set to an area such that the resonance frequency of the portion of vibrating body 21 corresponding to second partition 25d is not an integer multiple of the resonance frequency of the portion of vibrating body 21 corresponding to first partition 25c, and the area of small hole 29a is set to an area such that the resonance frequency of the portion of vibrating body 21 corresponding to small hole 29a is not an integer multiple of the resonance frequency of the portions of vibrating body 21 corresponding to first partition 25c and second partition 25d. This allows as many frequencies as possible to be set that can be resonated by intake sound amplifier 20, thereby expanding the frequency band over which intake sound is amplified.

[0055] In this embodiment, the second housing 26 has a bracket 14 for fixing the branch pipe 10 to the vehicle body. This stabilizes the position of the intake sound amplifier 20, thereby preventing the first housing 22 and the second housing 26 from being displaced relative to each other, thereby preventing a change in the resonant frequency or a reduction in the amplification effect of the intake sound.

[0056] In this embodiment, the vibrating body 21 is made of rubber. If the vibrating body 21 is made of rubber, it is easy to vibrate only the area partitioned by the lattice plate 25 or only the area where the small holes 29a are located. Furthermore, by changing the hardness, it is easy to adjust the resonance frequency. Therefore, the frequency band in which the intake sound is amplified can be expanded.

[0057] (Variation 1) FIG. 10 shows a first modification of this embodiment. In the first modification, the shape of the second lattice 125b of the lattice plate 125 differs from that of the previously described embodiment. Specifically, the second lattice 125b of the first modification has a larger diameter than the second lattice 25b of the previously described embodiment. Therefore, the partition area of the first partition section 125c of the first modification is smaller than that of the first partition section 25c of the previously described embodiment, and the partition area of the second partition section 125d of the first modification is larger than that of the second partition section 25d of the previously described embodiment.

[0058] The partition area of the second partition 125d is set to an area such that the resonance frequency of the portion of the vibrating body 21 corresponding to the second partition 125d is not an integer multiple of the resonance frequency of the portion of the vibrating body 21 corresponding to the first partition 125c, and the area of the small hole 29a is set to an area such that the resonance frequency of the portion of the vibrating body 21 corresponding to the small hole 29a is not an integer multiple of the resonance frequency of the portions of the vibrating body 21 corresponding to the first partition 125c and the second partition 125d.

[0059] In this first modification as well, the vibrating body 21 vibrates in resonance with intake pulsation from low to high frequencies, amplifying the intake noise. This makes it possible to widen the frequency band in which the intake noise is amplified.

[0060] (Variation 2) FIG. 11 shows a second modification of this embodiment. This modification differs from the previous embodiment in that the grid plate 225 is provided with a third grid 225e. Four third grids 225e are provided. The third grids 225e extend in the radial direction. The third grid 225e is located at the center of the pair of first grids 25a in the circumferential direction so as to divide the first partition portion 25c in the previous embodiment into two equal parts in the circumferential direction. The third grid 225e is integral with the first main body portion 23 and the second grid 25b.

[0061] By providing the third lattice 225e, there are a total of eight first partitions 225c in Modification 2. The partition area of the first partitions 225c in Modification 2 is approximately half the partition area of the first partitions 225c in the above-described embodiment.

[0062] The partition area of the second partition 225d is set to an area such that the resonant frequency of the portion of the vibrating body 21 corresponding to the second partition 225d is not an integer multiple of the resonant frequency of the portion of the vibrating body 21 corresponding to the first partition 225c, and the area of the small hole 29a is set to an area such that the resonant frequency of the portion of the vibrating body 21 corresponding to the small hole 29a is not an integer multiple of the resonant frequency of the portions of the vibrating body 21 corresponding to the first partition 225c and the second partition 225d.

[0063] In this second modification as well, the vibrating body 21 vibrates in resonance with intake pulsation from low to high frequencies, amplifying the intake noise. This makes it possible to widen the frequency band in which the intake noise is amplified.

[0064] (Other embodiments) The technology disclosed herein is not limited to the above-described embodiments, and can be substituted within the scope of the claims.

[0065] In the above-described embodiment, the lattice plate 25 is provided in the first housing 22, and the hole plate 29 is provided in the second housing 26. However, the present invention is not limited to this, and the hole plate may be provided in the first housing 22, and the lattice plate may be provided in the second housing 26.

[0066] In the above-described embodiment, the first grating 25a and the second grating 25b are embedded in the vibrating body 21, but the first grating 25a and the second grating 25b do not need to be embedded in the vibrating body 21 as long as they are in contact with the vibrating body 21.

[0067] The above-described embodiments are merely examples and should not be construed as limiting the scope of the present disclosure. The scope of the present disclosure is defined by the claims, and all modifications and variations that fall within the scope of the claims equivalents are within the scope of the present disclosure. [Industrial Applicability]

[0068] The technology disclosed herein is useful as an intake noise amplification device for an internal combustion engine. [Explanation of symbols]

[0069] 1. Internal combustion engine 2 Intake passage 10 Branch pipe 21 Vibration body 22 First cabinet 25 lattice plate 25a 1st grid 25b 2nd grid 25c First Section 25d Second compartment 26 Second cabinet 29-hole plate 29a small hole 125 lattice plate 125b 2nd grid 125c First Section 125d Second compartment 225 lattice plate 225a 1st grid 225b 2nd grid 225c First Section 225d Second compartment 225e 3rd grid R cabin V vehicle

Claims

1. An intake sound amplification device for an internal combustion engine, the device being provided in a branch pipe that branches off from an intake passage of the internal combustion engine mounted on a vehicle and transmits intake sound to a vehicle interior, a plate-shaped vibrator that vibrates due to intake pulsation from the intake passage; a first housing disposed at a portion of the branch pipe on the intake passage side with respect to the vibrator; a second housing disposed at a portion of the branch pipe on the vehicle cabin side with respect to the vibrator, the vibrator is sandwiched between the first housing and the second housing, one of the first housing and the second housing includes a grid plate having a grid that divides the vibrating body into a plurality of regions when viewed from a direction perpendicular to the surface of the vibrating body, The other of the first housing and the second housing includes a hole plate having a plurality of holes each having an area smaller than the smallest area of the region partitioned by the grid plate when viewed from a direction perpendicular to the surface of the vibrator.

2. 2. The intake sound amplifier for an internal combustion engine according to claim 1, the grid plate is provided in the first housing, The perforated plate is provided in the second housing of the intake sound amplifier for an internal combustion engine.

3. 2. The intake sound amplifier for an internal combustion engine according to claim 1, An intake sound amplification device for an internal combustion engine, wherein the number of holes in the hole plate is greater than the number of compartments in the grid plate.

4. 2. The intake sound amplifier for an internal combustion engine according to claim 1, The grid plate has a first partition having a relatively large area and a second partition having a relatively small area, An intake sound amplification device for an internal combustion engine, wherein the area of the hole is smaller than the area of the second partition portion.

5. The intake sound amplifier for an internal combustion engine according to any one of claims 1 to 4, The intake sound amplifier for an internal combustion engine, wherein the vibrator is made of rubber.

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