JP4595635B2 - Sound increaser - Google Patents

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.

As a conventional intake sound amplifying device, for example, there is one described in Patent Document 1. This intake sound amplifying device is provided with an opening on the side wall of the outside air introduction portion of the intake duct, and by connecting the opening and the dash panel with a flexible tube, the intake sound is efficiently introduced into the room, It produces a sporty sound.
JP 2004-218458 A (FIG. 1)

However, in the intake sound amplifying device described in Patent Document 1, since an opening is provided in the side wall of the outside air introduction portion, air introduced from the outside air introduction portion and sucked into the engine through the intake duct flows into the flexible tube. As a result, there was a problem that the intake air amount decreased.
Here, in order to solve this problem, an intake sound amplifying apparatus having the following configuration is conceivable. In this intake sound amplifying device, a communication pipe that communicates with the intake duct is attached to the outer peripheral surface of the intake duct, and the open end of the communication pipe is closed by the first diaphragm and the second diaphragm. The first additional pipe is connected to the closed opening end with the first diaphragm interposed therebetween, and the second additional pipe having a length different from that of the first additional pipe with the second diaphragm interposed therebetween. Are connected.

  In such an intake sound amplifying device, the first resonance frequency constituted by the first diaphragm and the first additional pipe is different from the second resonance frequency constituted by the second diaphragm and the second additional pipe. . For this reason, in the frequency band other than between the first resonance frequency and the second resonance frequency, the phase of the pressure fluctuation generated in the first communication pipe is opposite to the phase of the pressure fluctuation generated in the second communication pipe. Thus, the intake sound radiated from the first additional pipe and the second additional pipe is increased. As a result, the frequency band in which the intake sound can be increased can be expanded, and a more sporty sound can be obtained. In addition, since the intake duct is not provided with an opening, a reduction in intake air amount is prevented.

However, in the intake sound amplifying device described above, in the frequency band between the first resonance frequency and the second resonance frequency, the phase of the pressure fluctuation generated in the first communication pipe is the pressure generated in the second communication pipe. It becomes the same phase as the phase of fluctuation. For this reason, there is a problem that the intake sound emitted from the first additional pipe and the intake sound emitted from the second additional pipe cancel each other, and the sound increase effect of the intake sound is reduced.
The present invention has been made paying attention to the above problems, and the phase of the pressure fluctuation generated in the first communication pipe is opposite or opposite to the phase of the pressure fluctuation generated in the second communication pipe. It is an object of the present invention to provide an intake sound amplifying device that can increase the intake sound by setting the phase to.

In order to solve the above problems, the present invention includes a vent pipe in which a gas exists, and a pressure source that is connected to one open end of the vent pipe and generates a pressure fluctuation in the gas. The pressure fluctuation is a sound increase device composed of pressure fluctuations of a plurality of frequencies,
A first pressure fluctuation amplifying means attached to the outer peripheral surface of the vent pipe and amplifying the pressure fluctuation of the first frequency selected from the pressure fluctuations of the plurality of frequencies; A second pressure fluctuation amplifying means for amplifying the pressure fluctuation of the second frequency selected among the pressure fluctuations of the frequency of
The first pressure fluctuation amplifying means closes the opening end of the first series pipe that communicates with the vent pipe, the first series pipe, and the surface of the first series pipe by the pressure fluctuation of the first frequency. A first diaphragm that vibrates outward, and a first additional pipe that is connected to the first series pipe with the first diaphragm sandwiched between the first diaphragm and the first diaphragm, With
The second pressure fluctuation amplifying means closes an open end of the second communication pipe communicating with the vent pipe, the second communication pipe, and moves in the out-of-plane direction of the second communication pipe by pressure fluctuation of the second frequency. A second diaphragm that vibrates, and a second additional pipe coupled to the second communication pipe across the second diaphragm in a state where one opening end is closed by the second diaphragm,
The first series pipe is shorter than the first additional pipe,
The second communication pipe is shorter than the second additional pipe,
The first pressure fluctuation amplification means of the pressure variation of the first frequency amplified phase, Ri phase der phase opposite side of the pressure fluctuation of the second frequency, wherein the second pressure fluctuation amplification unit is amplified,
The first resonance frequency composed of the first diaphragm and the first additional tube matches or substantially coincides with the first frequency, and the second resonance frequency composed of the second diaphragm and the second additional tube is the above-mentioned there is provided a Zoon apparatus characterized that you match or substantially match the second frequency.

  According to the present invention, the intake sound is increased by setting the phase of the pressure fluctuation generated in the first continuous pipe to the phase opposite to the phase of the pressure fluctuation generated in the second communication pipe. A sporty sound can be obtained.

Embodiments of the present invention will be described below with reference to the drawings.
First, with reference to FIG.1 and FIG.2, the structure of 1st embodiment of this invention is demonstrated.
As shown in FIG. 1, the intake sound amplifying apparatus 1 according to the first embodiment of the present invention includes an intake duct 2, an engine 4, a first pressure fluctuation amplifying means 6, and a second pressure fluctuation amplifying means 8. It has.
The intake duct 2 is formed by a vent pipe in which a gas exists, and includes an air cleaner 10 and a throttle chamber 12. One open end of the intake duct 2 is connected to each cylinder 18 of the engine 4 via a surge tank 14 and each intake manifold 16 described later, and the other open end is opened to the outside air. . The air cleaner 10 has a filter part such as an oil filter, for example, and cleans the gas flowing in from the other opening end of the intake duct 2 by passing the filter part. The throttle chamber 12 is mounted between the air cleaner 10 and the surge tank 14 and is connected to an accelerator pedal (not shown). The amount of air flow from the air cleaner 10 to the surge tank 14 according to the amount of depression of the accelerator pedal. Increase or decrease.

  In the intake process, the engine 4 sucks the gas that flows in from the other opening end of the intake duct 2 and exists in the intake duct 2 into the cylinders 18 via the surge tank 14 and the intake manifolds 16. Further, the engine 4 forms a pressure source that generates an intake pulsation in the gas existing in the intake duct 2 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 4 is a pressure fluctuation generated in the gas existing in the intake duct 2, and this pressure fluctuation is composed of pressure fluctuations of a plurality of frequencies. That is, the intake pulsation generated in association with the intake operation of the engine 4 is composed of intake pulsations having a plurality of frequencies. In the present embodiment, an in-line four-cylinder engine having four cylinders will be described as an example of the engine 4, but the configuration of the engine 4 is not limited to this.

  The first pressure fluctuation amplifying means 6 includes a first series pipe 20, a first diaphragm 22, and a first additional pipe 24, and is generated at the position of the first attachment point P1 in the intake duct 2. Among the intake pulsations of a plurality of frequencies constituting the intake pulsation, the selected intake pulsation of the first frequency is amplified. The position of the first attachment point P1 is set between the air cleaner 10 and the throttle chamber 12 on the outer peripheral surface of the intake duct 2, and the detailed position thereof will be described later.

The first series pipe 20 has a cylindrical shape, and is attached to the position of the first attachment point P <b> 1 on the outer peripheral surface of the intake duct 2 so as to communicate with the intake duct 2.
The first diaphragm 22 is a plate having a shape capable of closing the open ends of the first series pipe 20 and the first additional pipe 24, and one of the open end of the first series pipe 20 and the first additional pipe 24. The open end is closed. The first diaphragm 22 vibrates in the out-of-plane direction of the first continuous pipe 20 due to the intake pulsation of the first frequency.

The first additional pipe 24 has a cylindrical shape, is formed by a pipe longer than the first series of pipes 20, and is connected to the first series of pipes 20 with the first diaphragm 22 interposed therebetween. Further, the first diaphragm 22 and the first additional tube 24 are formed so that the first resonance frequency constituted by the first diaphragm 22 and the first additional tube 24 coincides with the first frequency.
Here, for example, when the opening area of the first additional pipe 24 is equal to the opening area of the first continuous pipe 20, the resonance frequency of the first additional pipe 24 is set so that the length of the first additional pipe 24 is L ₁ , If the speed of sound is C, it can be obtained by the following calculation formula (1).
Resonance frequency (Hz) of the first additional tube 24 = (2n−1) C / (4L ₁ ) (1)
However, n is a positive integer.

  The second pressure fluctuation amplifying means 8 includes a second communication pipe 26, a second diaphragm 28, and a second additional pipe 30, and is generated at the position of the second attachment point P2 in the intake duct 2. Among the intake pulsations having a plurality of frequencies constituting the intake pulsation, the intake pulsation having the selected second frequency is amplified. The position of the second attachment point P2 is set at a position farther from the engine 4 than the position of the first attachment point P1 between the air cleaner 10 and the throttle chamber 12 on the outer peripheral surface of the intake duct 2. The position will be described later. The second frequency is higher than the first frequency.

The second communication pipe 26 has a cylindrical shape, and is attached in communication with the intake duct 2 at the position of the second attachment point P <b> 2 on the outer peripheral surface of the intake duct 2.
The second diaphragm 28 is a plate having a shape capable of closing the open ends of the second communication pipe 26 and the second additional pipe 30, and the open end of the second communication pipe 26 and one open end of the second additional pipe 30. Is blocked. The second diaphragm 28 vibrates in the out-of-plane direction of the second communication pipe 26 by the intake pulsation at the second frequency.

The second additional pipe 30 has a cylindrical shape, is formed by a pipe longer than the second communication pipe 26, and is connected to the second communication pipe 26 with the second diaphragm 28 interposed therebetween. The second diaphragm 28 and the second additional tube 30 are formed so that the second resonance frequency constituted by the second diaphragm 28 and the second additional tube 30 matches the second frequency.
Here, for example, if the opening area of the second additional pipe 30 is equal to the opening area of the second communicating pipe 26, the resonance frequency of the second additional pipe 30, the length of the second additional pipe 30 and L _2, the sound velocity If C is C, it is obtained by the following calculation formula (2).
Resonant frequency (Hz) of second additional pipe 30 = (2n−1) C / (4L ₂ ) (2)
However, n is a positive integer.

Next, with reference to FIG.2 and FIG.3, the position of the 1st attachment point P1 and the 2nd attachment point P2 is demonstrated.
When the phase of the intake pulsation of the first frequency and the phase of the intake pulsation of the second frequency are the same phase, as shown in FIG. 2, the frequency band between the first resonance frequency and the second resonance frequency ( In the range indicated by R), the phase of the intake pulsation at the first frequency is opposite to the phase of the intake pulsation at the second frequency. This is because the phase of the intake pulsation in the first additional pipe 24 is inverted in a frequency band higher than the first resonance frequency, and the phase of the intake pulsation in the second additional pipe 30 in a frequency band lower than the second resonance frequency. This is because it does not change. In FIG. 2, the relationship between the frequency (Hz) of the first frequency, the phase (deg), and the sound pressure level (db) is shown by a solid line, and the frequency (Hz) and phase (deg) of the second frequency. The relationship with the sound pressure level (db) is indicated by a broken line.

As a result, in the frequency band between the first resonance frequency and the second resonance frequency, intake sound radiated from the other opening end of the first additional tube 24 and radiation from the other opening end of the second additional tube 30. The intake sounds that are generated cancel each other out, and these intake sounds are reduced.
Therefore, as shown in FIG. 3, the positions of the first attachment point P1 and the second attachment point P2 are such that the phase of the intake pulsation at the first frequency and the phase of the intake pulsation at the second frequency are opposite, that is, The position is set so that the phase difference is 180 °. In FIG. 3, the position of the first attachment point P1 is indicated by I, and the position of the second attachment point P2 is indicated by II.

Next, functions and effects of this embodiment will be described.
When the engine 4 is driven, the intake pulsation generated in accordance with the intake operation of the engine 4 is propagated to the gas existing in the intake duct 2 via each intake manifold 16 and the surge tank 14.
Then, the intake air pulsation at the first frequency is propagated to the first diaphragm 22 via the first series pipe 20 at the position of the first attachment point P1. The first diaphragm 22, to which the first frequency intake pulsation is propagated, vibrates in the out-of-plane direction of the first continuous pipe 20 and propagates the first frequency intake pulsation to the first additional pipe 24.

At this time, since the intake pulsation of the first frequency propagated to the first additional pipe 24 matches the intake pulsation of the first resonance frequency constituted by the first diaphragm 22 and the first additional pipe 24, The intake pulsation of one frequency is amplified, and the increased intake sound is radiated from the other opening end of the first additional pipe 24.
Further, the intake pulsation of the second frequency is propagated to the second diaphragm 28 via the second communication pipe 26 at the position of the second attachment point P2. The second diaphragm 28 to which the intake pulsation of the second frequency is propagated vibrates in the out-of-plane direction of the second communication pipe 26, and propagates the intake pulsation of the second frequency to the second additional pipe 30.

At this time, since the intake pulsation of the second frequency propagated to the second additional pipe 30 matches the intake pulsation of the second resonance frequency constituted by the second diaphragm 28 and the second additional pipe 30, The intake pulsation of two frequencies is amplified, and the increased intake sound is radiated from the other opening end of the second additional pipe 30.
Therefore, in the intake sound amplifying device of the present embodiment, the intake sound radiated from the other opening end of the first additional pipe 24 and the second additional pipe 30 is increased, and a sporty sound can be produced. It becomes possible.

  Further, in the intake sound amplifying device of the present embodiment, the positions of the first attachment point P1 and the second attachment point P2 are opposite to each other in the phase of the intake pulsation at the first frequency and the phase of the intake pulsation at the second frequency. The position is set to be the phase. Therefore, as shown in FIG. 4, in the frequency band (shown as R in the figure) between the first resonance frequency and the second resonance frequency, the phase of the intake pulsation at the first frequency is the intake air at the second frequency. It is in phase with the pulsation phase. As a result, the intake sound radiated from the other opening end of the first additional pipe 24 and the intake sound radiated from the other opening end of the second additional pipe 30 are prevented from canceling out, and a wide frequency band is obtained. A sound increase effect of the intake sound can be obtained. In FIG. 4, the relationship between the frequency (Hz) of the first frequency, the phase (deg), and the sound pressure level (db) is indicated by a solid line, and the frequency (Hz) and phase (deg) of the second frequency. The relationship with the sound pressure level (db) is indicated by a broken line.

Furthermore, in the intake sound amplifying device of the present embodiment, the opening end of the first continuous pipe 20 is closed by the first diaphragm 22, and the opening end of the second communication pipe 26 is the second diaphragm 28. Therefore, the outflow of intake air to the outside of the intake duct 2 is prevented. Therefore, a reduction in the intake air amount of the engine 4 is prevented.
Further, in the intake sound amplifying device of the present embodiment, since the first series pipe 20 is shorter than the first additional pipe 24, the resonance frequency of the first series pipe 20 is higher than the first resonance frequency. It exists in a high frequency band. Similarly, since the 2nd communicating pipe 26 is shorter than the 2nd additional pipe 30, the resonant frequency of the 2nd communicating pipe 26 exists in a frequency band higher than a 2nd resonant frequency. Therefore, in the frequency band in which the intake pulsation is amplified, the first continuous pipe 20 and the second communication pipe 26 do not act as side branches, and the intake noise released to the atmosphere through the intake duct 2 is reduced. It never happens.

  In the intake sound amplifying device of the present embodiment, since the position of the second attachment point P2 is set at a position farther from the engine 4 than the position of the first attachment point P1, the second additional pipe The position of the first additional pipe 24 that is longer than 30 is closer to the engine 4 than the second additional pipe 30. Therefore, the first pressure fluctuation amplifying means 6 for amplifying the intake pulsation of the first frequency, which is a frequency higher than the second frequency and requires a large energy for the generation of the intake sound, is used as the engine that generates the intake pulsation. 4, the amplification efficiency of the intake pulsation of the first frequency is improved.

  In the intake sound amplifying apparatus of the present embodiment, the positions of the first attachment point P1 and the second attachment point P2 are set such that the phase of the intake pulsation at the first frequency and the phase of the intake pulsation at the second frequency are opposite to each other. However, the present invention is not limited to this. That is, if the effect of increasing the intake sound is exhibited, the phase of the intake pulsation at the first frequency and the phase of the intake pulsation at the second frequency are opposite to each other (the phase difference is other than 0 ° to 180 °). The position may be set.

  Further, in the intake sound amplifying device of the present embodiment, the intake pulsation of the first frequency and the intake pulsation of the first resonance frequency are matched, and the intake pulsation of the second frequency and the intake pulsation of the second resonance frequency are matched. However, the present invention is not limited to this. That is, if it is possible to increase the intake sound, the intake pulsation at the first frequency and the intake pulsation at the first resonance frequency are substantially the same, and the intake pulsation at the second frequency and the intake pulsation at the second resonance frequency are approximately the same. It is good also as a structure. Alternatively, the first series pipe 20 may be configured to have a first resonance frequency alone, and the second communication pipe 26 may be configured to have a second resonance frequency alone.

Furthermore, in the intake sound amplifying device of the present embodiment, the position of the second attachment point P2 is set at a position farther from the engine 4 than the position of the first attachment point P1, but the present invention is not limited to this. The position of the first attachment point P1 may be set at a position farther from the engine 4 than the position of the second attachment point P2.
Further, in the intake sound amplifying device of the present embodiment, the pressure source that generates the pressure fluctuation is the engine 4, but is not limited thereto, and the pressure source that generates the pressure fluctuation is, for example, a pump. Also good. Further, the pressure fluctuation is not limited to the intake pulsation but may be the exhaust pulsation.

Next, a second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 5, the intake sound amplifying apparatus 1 of the present embodiment is different in configuration from the first embodiment described above in the following points. That is, the first pressure fluctuation amplifying means 6 is composed of only the first continuous pipe 20, and the second pressure fluctuation amplifying means 8 is composed of only the second communication pipe 26.
The first series pipe 20 is a cylindrical hollow pipe, and is attached to the position of the first attachment point P <b> 1 on the outer peripheral surface of the intake duct 2 so as to communicate with the intake duct 2. Further, the first series pipe 20 is configured to have a first resonance frequency that matches the first frequency.

The second communication pipe 26 is a hollow pipe that is shorter than the cylindrical first communication pipe 20, and communicates with the intake duct 2 at the position of the second attachment point P <b> 2 on the outer peripheral surface of the intake duct 2. It is attached. The second communication pipe 26 has a second resonance frequency that matches the second frequency.
Other configurations are the same as those of the first embodiment described above.

Next, functions and effects of this embodiment will be described.
When the engine 4 is driven, the intake pulsation generated in accordance with the intake operation of the engine 4 is propagated to the gas existing in the intake duct 2 via each intake manifold 16 and the surge tank 14.
Then, the intake air pulsation of the first frequency is propagated to the first series pipe 20 at the position of the first attachment point P1. At this time, since the intake pulsation of the first frequency propagated to the first series pipe 20 matches the intake pulsation of the first resonance frequency of the first series pipe 20, the intake pulsation of the first frequency is The amplified intake sound is radiated from the open end of the first series pipe 20 after being amplified.

Further, the intake pulsation of the second frequency is propagated to the second communication pipe 26 at the position of the second attachment point P2. At this time, since the intake pulsation of the second frequency propagated to the second communication pipe 26 matches the intake pulsation of the second resonance frequency of the second communication pipe 26, the intake pulsation of the second frequency is amplified. The increased intake sound is radiated from the open end of the second communication pipe 26.
Therefore, with the intake sound amplifying device of the present embodiment, the intake sound radiated from the open ends of the first continuous pipe 20 and the second communication pipe 26 is increased, and a sporty sound can be produced. It becomes.
Further, in the intake sound amplifying device 1 of the present embodiment, the first pressure fluctuation amplifying means 6 is constituted by only the first series pipe 20, and the second pressure fluctuation amplifying means 8 is constituted by only the second communication pipe 26. Since it is configured, the structure of the apparatus is simplified and the manufacturing cost is reduced.
Other actions and effects are the same as those of the first embodiment described above.

Next, a third embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 6, the intake sound amplifying apparatus 1 of the present embodiment is different in configuration from the first embodiment described above in the following points. That is, the other opening end of the first additional pipe 24 and the other opening end of the second additional pipe 30 are arranged close to each other with the opening direction in the same direction.
Other configurations are the same as those of the first embodiment described above.

Next, functions and effects of this embodiment will be described.
Since the operation and effect until the intake sound is radiated from the other opening end of the first additional pipe 24 and the second additional pipe 30 are the same as those in the first embodiment described above, the description is omitted.
Therefore, in the intake sound amplifying device 1 of the present embodiment, the other opening end of the first additional pipe 24 and the other opening end of the second additional pipe 30 are arranged close to each other with the opening direction in the same direction. Yes. For this reason, it is possible to efficiently superimpose the intake sound radiated from the other opening end of the first additional pipe 24 and the intake sound radiated from the other opening end of the second additional pipe 30. The sound increase effect can be further improved.

Other actions and effects are the same as those of the first embodiment described above.
In the intake sound amplifying device 1 of the present embodiment, the other opening end of the first additional pipe 24 and the other opening end of the second additional pipe 30 are arranged close to each other with the opening direction in the same direction. However, the present invention is not limited to this. That is, if it is possible to improve the sound increase effect of the intake sound, the opening direction of the other opening end of the first additional pipe 24 and the other opening end of the second additional pipe 30 are set substantially in the same direction. May be arranged close together. Further, the other opening end of the first additional pipe 24 and the other opening end of the second additional pipe 30 may be adjacent to each other.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 7, the intake sound amplifying apparatus 1 of the present embodiment is different in configuration from the first embodiment described above in the following points. That is, the first pressure fluctuation amplifying means 6 is composed of the first series pipe 20, the first diaphragm 22, the large volume portion 32, and the small volume portion 34.
The large volume portion 32 has a cylindrical shape, and the volume of the hollow portion is larger than that of the first series pipe 20 and the small volume portion 34. The small volume portion 34 has a cylindrical shape, is formed so that the volume of the hollow portion is smaller than that of the large volume portion 32, and one open end communicates with the large volume portion 32.
The large volume portion 32 and the small volume portion 34 are formed so that the first resonance frequency constituted by the first diaphragm 22, the large volume portion 32, and the small volume portion 34 matches the first frequency. Has been.
Other configurations are the same as those of the first embodiment described above.

Next, functions and effects of this embodiment will be described.
When the engine 4 is driven, the intake pulsation generated in accordance with the intake operation of the engine 4 is propagated to the gas existing in the intake duct 2 via each intake manifold 16 and the surge tank 14.
Then, the intake air pulsation at the first frequency is propagated to the first diaphragm 22 via the first series pipe 20 at the position of the first attachment point P1. The first diaphragm 22 to which the intake pulsation of the first frequency is propagated vibrates in the out-of-plane direction of the first continuous pipe 20 and propagates the intake pulsation of the first frequency to the large volume portion 32 and the small volume portion 34. Let

At this time, the intake pulsation of the first frequency propagated to the large volume portion 32 and the small volume portion 34 is the first resonance frequency constituted by the first diaphragm 22, the large volume portion 32, and the small volume portion 34. This is consistent with the intake pulsation. For this reason, the intake pulsation of the first frequency is amplified, and the increased intake sound is radiated from the other opening end of the small volume portion 34.
In addition, since the description regarding the intake sound radiated | emitted from the other opening end of the 2nd additional pipe | tube 30 is the same as the effect | action and effect of 1st embodiment mentioned above, it abbreviate | omits.
Therefore, with the intake sound amplifying device of the present embodiment, the intake sound radiated from the other opening end of the small volume portion 34 and the second additional pipe 30 is increased, and a sporty sound can be produced. It becomes.

  Further, in the intake sound amplifying apparatus 1 of the present embodiment, the first pressure fluctuation amplifying means 6 is configured by the first series pipe 20, the first diaphragm 22, the large volume portion 32, and the small volume portion 34. Therefore, the first resonance frequency can be set in the low frequency band without extending the length of the first pressure fluctuation amplification means 6. For this reason, the force of the intake sound is increased, and a powerful and sporty sound can be produced. In addition, since the length of the first pressure fluctuation amplifying means 6 can be set to an arbitrary length, the degree of freedom in design is increased, and the intake sound amplifying apparatus 1 can be used under various conditions.

Other actions and effects are the same as those of the first embodiment described above.
In the intake sound amplifying apparatus 1 of the present embodiment, only the first pressure fluctuation amplifying means 6 is provided from the first series pipe 20, the first diaphragm 22, the large volume portion 32, and the small volume portion 34. Although configured, the present invention is not limited to this. In other words, the configuration of the second pressure fluctuation amplifying means 8 together with the first pressure fluctuation amplifying means 6 may be changed to the same configuration as the first pressure fluctuation amplifying means 6, or only the second pressure fluctuation amplifying means 8 is configured. May be changed.

Next, a fifth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 8, the intake sound amplifying apparatus 1 of the present embodiment is different in configuration from the first embodiment described above in the following points. That is, on the outer peripheral surface of the intake duct 2, the first pressure fluctuation amplifying means 6 and the second pressure fluctuation amplifying means 8 are attached to the other opening end side of the intake duct 2 rather than the air cleaner 10.
Other configurations are the same as those of the first embodiment described above.

Next, functions and effects of this embodiment will be described.
Since the operation and effect until the intake sound is radiated from the other opening end of the first additional pipe 24 and the second additional pipe 30 are the same as those in the first embodiment described above, the description is omitted.
Therefore, in the intake sound amplifying device 1 of the present embodiment, the configuration of the first embodiment described above, that is, the first pressure fluctuation amplifying means 6 and the second pressure fluctuation amplifying means 8 are attached at positions close to the engine 4. Any problems that may arise with the configured configuration are resolved. This problem is a problem that an anti-resonance frequency band in which the intake pulsation that vibrates the first diaphragm 22 and the second diaphragm 28 is reduced, and the sound increase effect of the intake sound is reduced.
However, in the intake sound amplifying apparatus 1 of the present embodiment, the first pressure fluctuation amplifying means 6 and the second pressure fluctuation amplifying means 8 are attached at a position far from the engine 4, and therefore anti-resonance that reduces the intake pulsation. The frequency band is reduced, and the sound increase effect of the intake sound can be further improved.
Other actions and effects are the same as those of the first embodiment described above.

FIG. 9 shows the intake sound radiated from the opening end of the intake duct and the intake sound radiated from the opening end of the additional pipe using the intake sound amplifying device of the present invention and the intake sound amplifying device of the comparative example. The result of having measured is shown.
As the intake sound amplifying apparatus of the present invention example, an intake sound amplifying apparatus 1 having the same configuration as that described in the first embodiment of the present invention as shown in FIG. 10A is used.

  As the intake sound amplifying apparatus of the comparative example, three kinds of intake sound amplifying apparatuses having configurations as shown in FIGS. 10B to 10D were used. In the intake sound amplifying apparatus 1 of the first comparative example shown in FIG. 10B, a communication rod 20 that communicates with the intake duct 2 is attached to the outer peripheral surface of the intake duct 2, and the opening end of the communication rod 20 is a diaphragm. In addition, the additional rod 24 is connected to the communication rod 20 through the diaphragm 22. Further, the intake sound amplifying device 1 of the second comparative example shown in FIG. 10C is the same as the intake sound amplifying device shown in FIG. 10B in that the length of the communication rod 20 is longer than that of the additional rod 24. It has been changed to be longer. Furthermore, in the intake sound amplifying device 1 of the third comparative example shown in FIG. 10D, the opening end of the communication pipe 20 is closed by the first diaphragm 22 and the second diaphragm 28, and the first diaphragm The first additional pipe 24 is connected with 22 interposed therebetween, and the second additional pipe 30 having a length different from that of the first additional pipe 24 is connected with the second diaphragm 28 interposed therebetween.

Next, a description will be given of the measurement results of the intake sound radiated from the opening end of the intake duct and the intake sound radiated from the opening end of the additional pipe.
As shown in FIG. 9, the intake sound amplifying device of the first comparative example has a narrow frequency range that can be increased, and the intake sound radiated from the open end of the additional pipe increases only in the vicinity of 500 Hz. It is sounding. In addition, the intake sound amplifying device of the second comparative example increases the intake sound radiated from the open end of the additional pipe at around 350 Hz in addition to around 500 Hz, but radiates from the open end of the intake duct. Inhalation sound is decreasing. Further, in the intake sound amplifying device of the third comparative example, the intake sounds radiated from the open ends of the two additional pipes cancel each other out in the frequency band between about 350 Hz and about 500 Hz.

  However, in the intake sound amplifying device of the present invention example, the intake sound radiated from the opening end of the intake duct is not muted, and the intake sounds radiated from the opening ends of the two additional pipes are mutually connected. There is no cancellation. As a result, the intake sound is increased in the frequency band between 350 Hz and 500 Hz (the range indicated by the oblique lines in FIG. 9), so that the intake sound can be increased in a wide frequency band.

In addition, in FIG. 9, the intake sound radiated | emitted from the opening end of the intake duct of the intake sound amplifying apparatus shown to Fig.10 (a)-(d) is each shown as AD. Moreover, the intake sound radiated | emitted from the opening end of the additional pipe | tube of the intake sound amplifying apparatus shown to (a)-(d) is each shown as a-d.
From the above measurement results, it was confirmed that the intake sound amplifying device of the present invention has a high effect of increasing the intake sound.

It is a figure which shows 1st embodiment of this invention. It is a figure which shows the relationship of the phase and sound pressure level of a 1st resonance frequency and a 2nd resonance frequency. It is a figure which shows the relationship of the phase of a 1st resonance frequency and a 2nd resonance frequency. It is a figure which shows the relationship of the phase and sound pressure level of a 1st resonance frequency and a 2nd resonance frequency. It is a figure which shows 2nd embodiment of this invention. It is a figure which shows 3rd embodiment of this invention. It is a figure which shows 4th embodiment of this invention. It is a figure which shows 5th embodiment of this invention. It is a figure which shows the relationship between the frequency and sound pressure level in the Example of this invention. It is a figure which shows the structure of the intake sound amplifying apparatus used for the Example of this invention, (a) shows the structure of the intake sound amplifying apparatus of the example of this invention, (b)-(d) is the intake air of a comparative example. The structure of a sound amplifying apparatus is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intake sound amplifying apparatus 2 Intake duct 4 Engine 6 1st pressure fluctuation amplification means 8 2nd pressure fluctuation amplification means 10 Air cleaner 12 Throttle chamber 14 Surge tank 16 Intake manifold 18 Cylinder 20 First serial pipe 22 First diaphragm 24 First additional pipe 26 Second communication pipe 28 Second diaphragm 30 Second additional pipe 32 Large volume part 34 Small volume part P1 First attachment point P2 Second attachment point R Between the first resonance frequency and the second resonance frequency Frequency band

Claims (8)

A vent pipe in which a gas is present, and a pressure source connected to one open end of the vent pipe and generating a pressure fluctuation in the gas, wherein the pressure fluctuation is composed of pressure fluctuations at a plurality of frequencies. In the sound increasing device,
A first pressure fluctuation amplifying means attached to the outer peripheral surface of the vent pipe and amplifying the pressure fluctuation of the first frequency selected from the pressure fluctuations of the plurality of frequencies; A second pressure fluctuation amplifying means for amplifying the pressure fluctuation of the second frequency selected among the pressure fluctuations of the frequency of
The first pressure fluctuation amplifying means closes the opening end of the first series pipe that communicates with the vent pipe, the first series pipe, and the surface of the first series pipe by the pressure fluctuation of the first frequency. A first diaphragm that vibrates outward, and a first additional pipe that is connected to the first series pipe with the first diaphragm sandwiched between the first diaphragm and the first diaphragm, With
The second pressure fluctuation amplifying means closes an open end of the second communication pipe communicating with the vent pipe, the second communication pipe, and moves in the out-of-plane direction of the second communication pipe by pressure fluctuation of the second frequency. A second diaphragm that vibrates, and a second additional pipe coupled to the second communication pipe across the second diaphragm in a state where one opening end is closed by the second diaphragm,
The first series pipe is shorter than the first additional pipe,
The second communication pipe is shorter than the second additional pipe,
The first pressure fluctuation amplification means of the pressure variation of the first frequency amplified phase, Ri phase der phase opposite side of the pressure fluctuation of the second frequency, wherein the second pressure fluctuation amplification unit is amplified,
The first resonance frequency composed of the first diaphragm and the first additional tube matches or substantially coincides with the first frequency, and the second resonance frequency composed of the second diaphragm and the second additional tube is the above-mentioned Zoon and wherein that you match or substantially match the second frequency.   The phase of the pressure fluctuation at the first frequency amplified by the first pressure fluctuation amplifying means is opposite to the phase of the pressure fluctuation at the second frequency amplified by the second pressure fluctuation amplifying means. The sound amplifying device described in 1.   The sound amplifying device according to claim 1 or 2, wherein one of the first pressure fluctuation amplifying means and the second pressure fluctuation amplifying means having a lower frequency to be amplified is attached to a position close to the pressure source. Said first communicating tube have a first resonant frequency that matches or substantially matches the first frequency communicates with the said vent tube, said second communicating pipe, the second communicates with the said vent tube Zoon apparatus according to any one of the Turkey of having a second resonant frequency that matches or substantially matches the frequency of claim 1, wherein 3. The first additional pipe is longer than the second additional pipe,
The position of the second attachment point for attaching the second communication pipe in the outer peripheral surface of the vent pipe is more than the position of the first attachment point for attaching the first continuous pipe in the outer peripheral surface of the vent pipe. Zoon apparatus according to claims 1 to 1 wherein one of the 4, wherein the position der Rukoto away from. The other open end of the first additional pipe other open end and a second additional tube, out the opening direction from claim 1, characterized in that disposed close towards the same direction or substantially the same direction 5 The sound amplifying device described in any one of the items . Said first additional pipe and at least one of the second additional pipe is any one of the claims 1 to at least one of the opening area and length, characterized in that it is composed of a plurality of different tubes 6 The sound amplifying device described in 1.   The pressure source is an engine, the vent pipe is an intake duct that forms an intake passage to the engine, and the pressure fluctuation is an intake pulsation generated in the intake duct. The sound amplifying device described in any one of them.

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