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(11) | EP 1 162 600 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
Active control of automotive induction noise Aktive Kontrolle des Kraftfahrzeugeinlasslärms Contrôle actif du bruit d'admission dans un moteur d'une voiture |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
FIELD OF THE INVENTION
[0001] This invention relates to an active control of automotive induction noise and, in particular, to an active dipole inlet using a drone cone speaker driver.
BACKGROUND OF THE INVENTION
[0002] Manufacturers have employed active and passive methods to reduce engine noise within the passenger compartment of motor vehicles. Such noise frequently emanates from the engine, travels through the air induction system and emanates out of the mouth of the air intake into the passenger compartment. Efforts have been made to reduce the amount of engine noise traveling through the air induction system. These efforts include the use of both passive devices such as expansion chambers and Helmholtz resonators and active devices involving anti-noise generators.
[0003] Active noise attenuation systems use a speaker to create a sound that attenuates engine noise. The sound created is out of phase with the engine noise and combines with the engine noise to result in its reduction. Generally, this sound is generated in proximity to the air induction system. In one such system, as known from EP 0 884 471, the speaker is placed in the mouth of air intake duct. An active noise control system for cancellation of noise in a duct is known from US 5 446 249.
[0004] At low sound frequencies, speakers of current active noise attenuation systems may experience a significant reduction of speaker response. As a consequence, current active noise attenuation systems reduce engine noise less than optimally at these frequencies. Undesirable engine sound may find its way back to the passenger compartment as a consequence.
[0005] A need therefore exists to improve speaker response of such systems at low sound frequencies without affecting the effectiveness of the speakers at higher frequencies.
OBJECT OF THE INVENTION
SUMMARY OF THE INVENTION
[0007] In a disclosed embodiment of this invention, an air induction system comprises an air induction system according to claim 1 and a method of noise attenuation according to claim 9.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
Figure 1 shows an embodiment of the invention.
Figure 2 shows a graph of the improved acoustic response afforded by the invention.
Figure 3 shows the embodiment of Figure 1 in relation to a vehicle throttle body and engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0009] There will now be described, by way of example, the best mode contemplated by the inventors for carrying out the invention. In the following description, numerous specific details are set out in order to provide a complete understanding of the present invention. It will be apparent, however, to those skilled in the art, that the present invention may be put into practise with variations of this specific.
[0010] Figure 1 shows an embodiment of the invention. The air induction system comprises air induction body 10, speaker 14 with first diaphragm 18, and second diaphragm 22, which is spaced from first diaphragm 18. As can bee seen from the drawing, speaker 14 and first diaphragm 18 are disposed about air induction body 10. While first diaphragm 18 may be of a design well known, second diaphragm 22 is preferably flexible.
[0011] The air induction system includes a flow body 26 interconnecting first diaphragm 18 and second diaphragm 22. Here, the flow body is a tube, although one skilled in the art may employ other forms to perform the same function of creating an inductive mass. Seal 30 and seal 34 may serve to interconnect flow body 26 to first diaphragm 18 and second diaphragm 22, respectively. Mouth 38, an opening as known in the art, may be part of air induction body 10. It is preferable that second diaphragm 22 be disposed about mouth 38 as pictured. Additionally, air filter 42 may also be disposed in air induction body 10 to filter incoming air in the direction of arrow A, which is in the direction of the vehicle engine.
[0012] Control unit 46, as known in the art, is in communication with speaker 14 to thereby control sound output to attenuate engine noise. In this configuration, control unit 46 generates a signal through speaker 14 and first diaphragm 18. The signal is transmitted to second diaphragm 22. The signal is transmitted through a sealed flow body such as a tube. In response to this signal, second diaphragm 22 generates a noise attenuating sound, which, as known, is generally out of phase with engine noise to thereby cancel sound. The signal is thus transmitted through an inductive mass, which improves speaker response at low frequency ranges.
[0013] Figure 2 illustrates the benefit of the system. Speaker response is shown over sound frequency. Line 50 illustrates speaker response of prior art systems over a wide frequency range. As shown, speaker response deteriorates at low sound frequencies. With the device of Figure 1, as shown by line 54 (dashed lines), speaker response improves to permit noise attenuation at low frequency ranges without sacrificing speaker response at higher frequency ranges.
an air induction body (10);
a speaker (14) disposed within the air induction body (10); a first diaphragm (18) associated with said speaker (14) and a control unit (46) in communication with the speaker (14) having means to generate a signal to the speaker (14) with first diaphragm (18), characterized by
a second diaphragm (22) spaced from said first diaphragm (18), a flow body (26) interconnecting said first diaphragm (18) and said second diaphragm (22) in a sealed manner thereby creating an inductive mass wherein, in use, the signal emitted by the first diaphragm (18) is transmitted through said flow body (26) to said second diaphragm (22) such that said second diaphragm (22) generates a noise attenuating sound.
generating a signal from a first diaphragm (18) disposed in an air induction body (10), characterized in
transmitting said signal through a flow body (26) to a second diaphragm (22), said flow body (26) interconnecting said first diaphragm (18) and said second diaphragm (22) in a sealed manner thereby creating an inductive mass; and thereby
generating a noise attenuating sound from the second diaphragm (22).
ein Luftansauggehäuse (10);
einen Lautsprecher (14), der im Luftansauggehäuse (10) angeordnet ist; eine erste Membran (18), die mit dem besagten Lautsprecher (14) gekoppelt ist, und eine Steuerung (46) in Datenaustausch mit dem Lautsprecher (14), die über Mittel verfügt, um ein Signal an den Lautsprecher (14) mittels der ersten Membran (18) zu erzeugen, gekennzeichnet durch
eine zweite Membran (22), die mit einem Abstand zur besagten ersten Membran (18) angeordnet ist, einen Strömkörper (26), der die erste Membran (18) und die besagte zweite Membran (22) in abgedichteter Weise miteinander verbindet, wodurch eine induktive Masse erzeugt wird, wobei im Betrieb das von der ersten Membran (18) ausgegebene Signal durch den besagten Strömkörper (26) zur besagten zweiten Membran (22) übertragen wird, so dass besagte zweite Membran (22) ein Geräusch zur Geräuschdämpfung erzeugt.
Erzeugen eines Signals durch eine erste Membran (18), die in einem Luftansauggehäuse (10) angeordnet ist, dadurch gekennzeichnet, dass
das besagte Signal durch einen Strömkörper (26) zu einer zweiten Membran (22) übertragen wird, wobei besagter Strömkörper (26) besagte erste Membran (18) und besagte zweite Membran (22) in abgedichteter Weise miteinander verbindet, wodurch eine induktive Masse erzeugt wird, und dadurch
Erzeugen eines Geräuschs zur Geräuschdämpfung durch die zweite Membran (22).
un corps d'admission d'air (10) ;
un haut-parleur (14) disposé à l'intérieur du corps d'admission d'air (10) ;
un premier diaphragme (18) associé audit haut-parleur (14), et
une unité de commande (46) en communication avec le haut-parleur (14) comportant un moyen de produire un signal pour le haut-parleur (14) avec le premier diaphragme (18),
caractérisé par :un second diaphragme (22) espacé par rapport audit premier diaphragme (18), et
un corps d'écoulement (26) interconnectant ledit premier diaphragme (18) et ledit second diaphragme (22) d'une manière étanche en créant par là une masse d'admission,
en sachant que, en fonctionnement, le signal émis par le premier diaphragme (18) est transmis à travers ledit corps d'écoulement (26) audit second diaphragme (22) de telle sorte que ledit second diaphragme (22) produise un son atténuant le bruit.
produire un signal depuis un premier diaphragme (18) disposé dans un corps d'admission d'air (10), caractérisé par le fait de
transmettre ledit signal à travers un corps d'écoulement (26) à un second diaphragme (22), ledit corps d'écoulement (26) interconnectant ledit premier diaphragme (18) et ledit second diaphragme (22) d'une manière étanche en créant par là une masse d'admission, et
produire ainsi un son atténuant le bruit depuis le second diaphragme (22).