1. Field of the Invention
The present invention relates to an intake sound adjusting device particularly provided with a mechanism capable of generating an intake sound having a specific frequency band.
2. Description of Related Art
In an internal combustion engine, pulsating (pulsation) sound or noise of intake air introduced into an internal combustion engine due to reciprocating motion of a piston or an intake valve disposed within the internal combustion engine. Since this intake pulsating sound has a wide band range, this is generally considered as “noise”. In order to reduce such intake pulsating sound as noise, a resonator or like is generally disposed in an intake passage to thereby reduce noise of the specific frequency range calculated on the basis of the Helmholtz's Resonance Theory.
However, for some cars such as called “sporty cars”, it is required to generate a vigorous powerful intake sound in a vehicle interior in order to produce an acceleration feel, and in order to satisfy such requirement, in the known art, there is provided a sound quality controlling device capable of producing a powerful intake sound in the vehicle interior only by amplifying a desired frequency band region or area of the intake sound of the wide band range or area.
For the sound quality controlling device mentioned above, prior art provides some sound quality controlling devices in which various attempts have been made for the purpose of tuning a sound pressure characteristic of a desired frequency band.
For example, Japanese Patent Laid-open Publication No. 2005-139982 (Patent Document 1) discloses a sound quality controlling device equipped with a resonator, which is provided with a resonator body (resonating member) oscillating in response to intake air pulsation in a intake unit, a volume chamber connected to the intake unit through the resonating body, and a volume chamber opening section communicating the interior space of the volume chamber with an external side. The interior space of the volume chamber and the interior of the intake unit is sectioned by the resonator body, and by the oscillation of the resonator body, the sound pressure of the specific frequency band area is released externally from the volume chamber opening section.
Furthermore, an intake device disclosed in Japanese Patent Laid-open Publication No. 2006-83787 (Patent Document 2) is provided with an intake passage for introducing sucked air into the internal combustion engine and a resonator passage branched from the intake passage, in which the resonator passage has one end opened to atmosphere and the other end connected to the intake passage. The resonator passage has a length set to be suitable for applying sound pressure of the specific frequency band area to the intake (sucked) air.
However, according to the structures or constructions of the sound quality controlling device disclosed in the Patent Document 1 and the intake device disclosed in the Patent Document 2, there may cause a case where a sound in an area other than the specific frequency band area, which constitute cause or factor of an offensive loud noise or a vehicle exterior noise. Moreover, in a case of changing the specific frequency band in the sound quality tuning operation, it is obliged to re-design volume or size of the volume chamber and the resonator, which makes it difficult to easily perform the sound quality tuning.
The present invention was conceived in consideration of the circumstances encountered in the prior art such as mentioned above, and an object of the present invention is to provide an intake sound adjusting device capable of releasing a specific frequency band and easily performing a sound quality tuning even with a simple structure.
The above and other objects can be achieved according to the present invention by providing an intake sound adjusting device comprising: an intake passage; a tubular branch passage branched from the intake passage; and an oscillating member disposed within the branch passage, wherein the oscillating member has an oscillating portion disposed so as to close an interior of the branch passage and a controlling portion extending from the oscillating portion in a direction along an extending direction of the branch passage.
In the above aspect, the embodiments may be preferred.
It may be desired that the controlling portion extends from the oscillating portion toward the intake passage.
The oscillating portion may be changed in an arranging position inside the branch passage along the extending direction thereof.
It may be desired that the oscillating portion has a length to be changed along the extending direction of the branch passage.
It may be desired that the oscillating portion has a conical shape projecting from an inner wall side of the branch passage toward the intake passage.
It may be desired that the oscillating portion is formed into flat-plate shape vertically intersecting the extending direction of the branch passage.
It may be desired that at least one of the oscillating portion and the controlling portion is formed of resin material or rubber.
According to the intake sound adjusting device of the present invention of the structures mentioned above, the oscillating member having the controlling portion extending along the extending direction of the branch passage is provided. The controlling portion is oscillated only in the specific frequency band, so that the sound in the specific frequency band can be generated. Furthermore, the frequency band of the intake sound to be generated can be easily changed by changing the position of the oscillating member in the branch passage, thus easily performing the sound quality tuning.
The nature and further characteristic features of the present invention will be made clearer from the following description made with reference to the accompanying drawings.
In the accompanying drawings:
A preferred embodiment of the present invention will be described hereunder with reference to the accompanying drawings. It is further to be noted that the described embodiment does not necessarily limit the invention recited in appended claims and all combination of characteristic features explained in the embodiment is not necessarily essential for the solution of the invention.
With reference to
An intake sound adjusting device 10 according to an embodiment of the present invention includes a tubular branch passage (channel) 20 branched from the intake passage (channel) 11 so as to extent toward a clean side of the intake passage 11 (downstream side of the air cleaner 12) and an oscillating member 30 disposed within the branch passage 20.
As shown in
The oscillating portion 31 has a conical shape projecting toward the intake passage side 11 and is formed in a hollow corn shape opened in the open end 21 of the branch passage 20. The oscillating portion 31 has an outer configuration substantially identical to the sectional shape of the branch passage 20 so as to close the interior of the branch passage 20 to thereby prevent dust and dirt from entering the interior of the branch passage 20 through the open end 21 thereof.
The controlling portion 32 has a length in its width direction smaller than an inner diameter of the branch passage 20 so as to prevent the controlling portion itself from oscillating. The controlling portion 32 has a length along the extending direction of the branch passage 20 may be appropriately set so that the controlling portion 32 is oscillated with a specific frequency. In addition, the controlling portion 32 is formed on the side of the intake passage 11 of the oscillating portion 31. Further, the oscillating member 30 may be formed of rubber, synthetic resin or other materials as far as it can be oscillated in response to a specific frequency.
It is further to be noted that the oscillating portion 31 of the described embodiment may be various shapes without limiting to the conical shape mentioned above, such as for example, as shown in
A part of the intake pulsating sound generated in the internal combustion engine E is introduced into the branch passage 20 branched from the intake passage 11 before deadening (silencing) the pulsating sound by a silencer such as resonator. In this branch passage 20, there is arranged the oscillating member 30 provided with the controlling portion 32 so that the controlling portion 32 is oscillated by the specific frequency by the intake pulsating sound introduced from the intake passage 11, and this oscillation is transferred to the oscillating portion 31 to thereby release only the specific frequency from the open end 21 of the branch passage 20.
Hereunder, a result in an experiment of the intake sound adjusting device 10 according to the present embodiment will be explained with reference to experimental examples.
With reference to
As can be seen from
Next, a method for tuning a sound quality of an intake pulsating sound by adjusting the specific frequency will be described with reference to the results of the experiments.
As can be seen from the results of the experiments shown in
As can be seen from
As mentioned hereinabove, by constructing the oscillating member 30 so that the inserting position of the oscillating member 30 is changeable in the branch passage 20 along the extending direction thereof, the specific frequency can be easily adjusted, and the sound quality tuning of the intake pulsating sound can be performed. Furthermore, by changing the length of the controlling portion 32 along the extending direction of the branch passage 20, the frequency band, which is desired to be more deadened in sound, can be adjusted, and hence, the sound quality tuning of the intake pulsating sound can be effectively performed.
As can be seen from
As mentioned hereinbefore, according to the intake sound adjusting device of the present invention, the sound quality can be tuned so as to obtain an intake pulsating sound emphasizing only the specific frequency with a simple structure, and it becomes possible to vanish frequency band ranges causing offensive noises or vehicle exterior noises. Therefore, in the sound quality tuning operation, the specific frequency ban can be easily changed.
It is further to be noted that the present invention is not limited to the described embodiment and many other changes and modifications may be made without departing from the scopes of the appended claims.
For example, in the described embodiment, although the oscillating portion 31 and the controlling portion 32 are formed of rubber, only either one of them may be formed of rubber, or either one of them may be formed of synthetic resin.
Furthermore, in the present embodiment, although branch passage (channel) 20 is formed in shape of tube, a porous plate may be attached to the open end 21 of the branch passage 20, or the open end 21 may be branched into a plurality branched passages which may be optionally changed in lengths to thereby adjust the sound quality of the intake pulsating sound.
Number | Date | Country | Kind |
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2009-051893 | Mar 2009 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
4903486 | Finkle | Feb 1990 | A |
5917161 | Fuhrmann | Jun 1999 | A |
7441527 | Hayashi et al. | Oct 2008 | B2 |
7487857 | Wolf | Feb 2009 | B2 |
7506626 | Sasaki et al. | Mar 2009 | B2 |
20050155816 | Alcini et al. | Jul 2005 | A1 |
20060249328 | Ichikawa et al. | Nov 2006 | A1 |
20090000587 | Seko et al. | Jan 2009 | A1 |
Number | Date | Country |
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2005-139982 | Jun 2005 | JP |
2006-083787 | Mar 2006 | JP |
Number | Date | Country | |
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20100224439 A1 | Sep 2010 | US |