CN203867673U - Active noise control system used for automobile exhaust system - Google Patents
Active noise control system used for automobile exhaust system Download PDFInfo
- Publication number
- CN203867673U CN203867673U CN201420287385.XU CN201420287385U CN203867673U CN 203867673 U CN203867673 U CN 203867673U CN 201420287385 U CN201420287385 U CN 201420287385U CN 203867673 U CN203867673 U CN 203867673U
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- noise
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- chamber
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- control system
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- 230000003584 silencer Effects 0.000 claims abstract description 41
- 230000008030 elimination Effects 0.000 claims abstract description 7
- 238000003379 elimination reaction Methods 0.000 claims abstract description 7
- 239000002245 particle Substances 0.000 claims description 4
- 238000012937 correction Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 2
- 238000012545 processing Methods 0.000 claims description 2
- 239000003054 catalyst Substances 0.000 abstract 3
- 238000002485 combustion reaction Methods 0.000 description 12
- 230000030279 gene silencing Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 238000012360 testing method Methods 0.000 description 2
- 239000002912 waste gas Substances 0.000 description 2
- 239000011358 absorbing material Substances 0.000 description 1
- 230000008033 biological extinction Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
Landscapes
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Exhaust Silencers (AREA)
Abstract
The utility model relates to an active noise control system used for an automobile exhaust system. The active noise control system comprises an exhaust pipe, a three-way catalyst and a control system body, wherein the exhaust pipe is connected to an engine of an automobile, the three-way catalyst is connected between the engine and a tail pipe of the exhaust pipe, and the control system body is connected with both the engine and the tail pipe. The active noise control system further comprises an active silencer which is connected between the three-way catalyst and the tail pipe. The active silencer is provided with a vibrating plate. A control signal outputted by the control system body is transmitted to the active silencer to be used for controlling the vibrating plate to vibrate so that reverse sounds can be generated for eliminating medium and low frequency noise. According to the active noise control system, reverse sounds are generated through vibration of the vibrating plate in the active silencer, the problem of reliability and durability of a loudspeaker in a traditional active silencer is solved, and meanwhile the noise elimination volume and the weight of the exhaust system can be further reduced and the burning efficiency of vehicles is improved.
Description
Technical field
The utility model belongs to field of acoustics, relates to a kind of active noise controlling system for automobile exhaust system.
Background technique
In Vehicle Driving Cycle process, the work cycle (particularly suck and compressed fuel-air mixture, light/expand and discharge the fuel-air mixture of burning) recurring due to internal-combustion engine has generated noise.These noises on the one hand as solid-borne sound by internal-combustion engine and emit to the outside of internal-combustion engine as airborne sound.On the other hand, noise is discharged by the vent systems of internal-combustion engine together with the fuel-air mixture of airborne sound and burning.
It is disadvantageous that these noises are usually considered to.Can and therefore conventionally not form as the problem of noise control using high efficiency decay by the noise of internal-combustion engine as solid-borne sound.But the silencing apparatus that need to arrange before vent systems entrance as airborne sound reduces.At present, conventional muffler, by its noise elimination mechanism, can be divided into dissipative muffler, reactive muffler and impedance muffler etc.The noise-cancelling theory of dissipative muffler is the sound-absorbing material utilizing in pipeline, partly absorbs the acoustic energy along pipe transmmision.Reactive muffler is pipeline and the perforated pipe resonance sound-absorbing structure etc. that utilizes various shapes, size, causes sound wave in system middle impedance mismatch, makes sound wave in pipeline and resonant cavity, come back reflective, consume, thereby reaches the object of noise elimination.Impedance muffler is that dissipative muffler and reactive muffler are combined, thereby realizes the object that wideband is eliminated the noise.These silencing apparatuss have such shortcoming at present: the in the situation that of the high extinction efficiency of needs, they need a larger volume and apply relatively high resistance to the fuel-air mixture of burning.The combustion efficiency and the fuel consumption that have reduced vehicle increase.
As an alternative or supplementary silencing apparatus, so-called active noise controlling system (as shown in Figure 1) has developed one period of time, the airborne sound that its anti-sound that electroacoustics is generated (but with the noise of cancellation being had to same-amplitude having an opposite phase sound wave of (oppositely)) is added to and is generated by internal-combustion engine and conduct in vent systems.
Accompanying drawing 1 is the Block Diagram of active noise controlling system of the prior art, the tail pipe 1 that comprises loudspeaker 3, is connected to the outlet pipe 4 on internal-combustion engine 6 and is all connected with outlet pipe 4 with the housing of loudspeaker 3, one end of tail pipe 1 has 2 connection mouths, 2 connection mouths are connected with the housing of loudspeaker 3 with the air outlet end of outlet pipe 4 respectively, the other end of tail pipe 1 has a mouth 2 so that the waste gas of conduction in outlet pipe 4 is discharged into outside, between outlet pipe 4 and internal-combustion engine 6, is also connected with catalytic converter 7.This active noise controlling also comprises the engine control of working for controlling combustion engine 68 and the anti-acoustic control system 10 that are electrically connected with internal-combustion engine 6, anti-acoustic control system 10 is unitarily formed with engine control 8, and be therefore integrated in engine control 8, anti-acoustic control system 10 is connected with loudspeaker 3, between loudspeaker 3 and anti-acoustic control system 10, is connected with amplifier 11.In tail pipe 1, be provided with error microphone 5, error microphone 5 is electrically connected to anti-acoustic control system 10, is provided for determining the temperature probe 9 of exhaust gas temperature in outlet pipe 4, and temperature probe 9 is connected in anti-acoustic control system 10.
As an alternative or the supplementary silencing apparatus by employing active noise controlling system, the structural volume of vent systems can be reduced to 60%, and weight can reduce to 40%, and exhaust back pressure can be reduced to 150 millibars (mbar).But due to problems such as vent systems internal high temperature and susceptibility-to-corrosions, the reliable durable of loudspeaker is difficult to be resolved.
Summary of the invention
Technical problem to be solved in the utility model is to overcome the deficiencies in the prior art, and a kind of active noise controlling system for automobile exhaust system is provided.
For solving above technical problem, the utility model adopts following technological scheme:
A kind of active noise controlling system for automobile exhaust system, comprise the outlet pipe on the motor that is connected to described automobile, the control system that is connected to the ternary catalyzing unit between described motor and the tail pipe of described outlet pipe and is electrically connected with described motor, described active noise controlling system also comprises the active silencer being connected between described ternary catalyzing unit and described tail pipe, described active silencer has vibrating plate, the control signal of described control system output transfers to described active silencer and eliminates Middle and low frequency noise for the anti-sound of generation of vibration of controlling described vibrating plate, described Middle and low frequency noise is the noise of frequency at 0～1000Hz.
Described active silencer comprises housing, described vibrating plate is fixedly installed in described housing and described housing is separated into the first chamber and the second chamber, described active silencer also comprises and is arranged on the piezoelectric chip being connected on described vibrating plate and with described control system, the control signal control that described piezoelectric chip is exported by described control system produces vibration, and the radiated noise that the vibration of described piezoelectric chip drives described vibration plate vibrates to produce corresponding frequencies and phase place is eliminated described Middle and low frequency noise.
Described active silencer also comprises the suction tude and the steam outlet pipe that are fixedly installed on described housing two ends, one end of described suction tude is positioned at outside described housing and is connected with described outlet pipe, and the other end of described suction tude is through straight-through described the second chamber of described the first chamber; One end of described steam outlet pipe is positioned at outside described housing and is connected with described tail pipe, and the other end of described steam outlet pipe is connected on described housing and with described the second chamber and is communicated with.
Described active silencer also comprises the filter screen being fixedly installed in described the second chamber, and described filter screen is for filtering the particle of tail exhaust body, and the other end of described suction tude is through described filter screen.
On described vibrating plate, evenly arrange and offer the multiple air holes for the first chamber described in balance and described the second chamber pressure along the circumferencial direction of described vibrating plate, described the first chamber and described the second chamber are only connected by described air hole.
Described control system comprises the control unit that is electrically connected with described motor, be electrically connected with described control unit and can be arranged in the error microphone of described active silencer rear end and be connected to described control unit and described active silencer between frequency variator, described frequency variator is electrically connected with described control unit and described piezoelectric chip respectively, described frequency variator receives the control signal of described control unit output, and the radiated noise that then drives described vibration plate vibrates to produce corresponding frequencies and phase place for controlling the vibration of described piezoelectric chip is eliminated described Middle and low frequency noise; Described error microphone and guides control signal described in described control unit correction for the soundproof effect of active silencer described in Real-time Feedback.
Described control unit comprises the control chip, processor and the storage that integrate, and described control chip produces the anti-acoustic signal of corresponding frequencies and phase place for frequency variator described in the feedback signal of feeding back according to described error microphone or the described engine behavior SC sigmal control of feeding back by described motor; Described processor is used for processing in real time the primary signal of described error microphone or described motor feedback, and result of calculation is fed back to described control chip; Described storage is tested the original occurrence characteristics curve recording or is stored the real-time control data that described processor calculates for storing, described control system also comprises storage battery, described storage battery is for to the power supply of described control unit, and described storage battery is also used to piezoelectric chip vibration described in described transducer drive that power is provided.
Between described ternary catalyzing unit and described active silencer, be also provided with dissipative muffler, described dissipative muffler is for passive elimination high frequency noise, and described high frequency noise is the noise of frequency more than 1000Hz.
Due to the enforcement of technique scheme, the utility model compared with prior art tool has the following advantages:
Active noise controlling system of the present utility model adopts the anti-sound of generation of vibration of vibrating plate, not only solve the reliable durable problem of loudspeaker of the prior art, can further reduce noise elimination volume and the weight of vent systems, improve the combustion efficiency of vehicle simultaneously.
Brief description of the drawings
Fig. 1 is the skeleton diagram of active noise controlling system of the prior art;
Fig. 2 is the skeleton diagram of active noise controlling system of the present utility model;
Fig. 3 is the structural representation of the active silencer of the utility model active noise controlling system;
In Fig. 2 ~ 3, the represented name of numeral is called:
1, motor; 2, ternary catalyzing unit; 3, dissipative muffler; 4, outlet pipe; 5, active silencer; 6, tail pipe; 7, error microphone; 8, frequency variator; 9, control unit; 10, control chip; 11, processor; 12, storage; 13, storage battery; 14, suction tude; 15, housing; 16, steam outlet pipe; 17, vibrating plate; 18, piezoelectric chip; 19, air hole; 20, filter screen; 21, the first chamber; 22, the second chamber.
Embodiment
Below in conjunction with Figure of description, the utility model is further described.
As shown in Fig. 2 ~ 3, a kind of active noise controlling system for automobile exhaust system, comprise the outlet pipe 4 on the motor 1 that is connected to automobile, be connected to the ternary catalyzing unit 2 between motor 1 and the tail pipe 6 of outlet pipe 4, the control system being electrically connected with motor 1, be connected to the active silencer 5 between ternary catalyzing unit 2 and tail pipe 6, active silencer 5 has vibrating plate 17, the control signal of control system output transfers to active silencer 5 and eliminates Middle and low frequency noise for the anti-sound of generation of vibration of controlling vibrating plate 17, Middle and low frequency noise is the noise of frequency at 0～1000Hz.This active noise controlling system also comprises the dissipative muffler 3 being arranged between ternary catalyzing unit 2 and active silencer 5, and dissipative muffler 3 is the noise of frequency more than 1000Hz for passive elimination high frequency noise high frequency noise.
As shown in Figure 3, active silencer 5 comprises housing 15, vibrating plate 17 is fixedly installed in housing 15 and housing 15 is separated into the first chamber 21 and the second chamber 22, active silencer 5 also comprises and is arranged on the piezoelectric chip 18 being connected on vibrating plate 17 and with control system, piezoelectric chip 18 is provided with multiple, multiple piezoelectric chips 18 are evenly arranged along vibrating plate 17 circumferencial directions, the control signal control that piezoelectric chip 18 is exported by control system produces vibration, and the radiated noise that the vibration of piezoelectric chip 18 drives vibrating plate 17 to produce corresponding frequencies and phase place is eliminated Middle and low frequency noise.
In the present embodiment, active silencer also comprises the suction tude 14 and the steam outlet pipe 16 that are fixedly installed housing two ends, and one end of suction tude 14 is positioned at outside housing 15 and is connected with outlet pipe 4, and the other end of suction tude 14 is through straight-through the second chamber 22 of the first chamber 21; One end of steam outlet pipe 16 is positioned at outside housing 15 and is connected with tail pipe 6, and the other end of steam outlet pipe 16 is connected on housing 15 and with the second chamber 22 and is communicated with.This active silencer 5 also comprises the filter screen 20 being fixedly installed in the second chamber 22, and filter screen 20 is for the particle that filters tail exhaust body to prevent particle erosion piezoelectric chip 18 and vibrating plate 17, and the other end of suction tude 14 is through filter screen 20.
For the air pressure of balance the first chamber 21 and the second chamber 22, on vibrating plate 17, evenly arrange and offer multiple air hole 19, the first chambers 21 and 22 of the second chambers are connected by air hole 19 along the circumferencial direction of vibrating plate 17.
Control system in the present embodiment comprises the control unit 9 that is electrically connected with motor 1, be electrically connected with control unit 9 and can be arranged in the error microphone 7 of active silencer 5 rear ends and be connected to control unit 9 and active silencer 5 between frequency variator 8, frequency variator 8 is electrically connected with control unit 9 and piezoelectric chip 18 respectively, the control signal that frequency variator 8 reception control units 9 are exported, then drives the radiated noise of vibrating plate 17 generation of vibration corresponding frequencies and phase place to eliminate Middle and low frequency noise for controlling the vibration of piezoelectric chip 18; Error microphone 7 and guides control unit 9 Correction and Control signals for the soundproof effect of Real-time Feedback active silencer 5.
Wherein, in control unit 9, store indicatrix, the data of indicatrix are carried out real vehicle test according to the parametric variable of the working state of motor 1 and are determined; Thereby each temperature of the waste gas whether control unit 9 is suitable for the indicatrix of the signal receiving from error microphone 7 and the definite selection of threshold values comparison to conduct in vent systems changes indicatrix or according to real-time result of calculation, control signal is revised in the time exceeding threshold values.
Control unit in the present embodiment comprises the control chip 10, processor 11 and the storage 12 that integrate, and control chip 10 produces the anti-acoustic signal of corresponding frequencies and phase place for the feedback signal of feeding back according to error microphone 7 or the motor feeding back by motor 11 working state signal control frequency variator 8; Processor 11 is for the primary signal that in real time process errors microphone 7 or motor 1 feed back, and result of calculation is fed back to control chip 10; The real-time control data that storage 12 calculates for storing the original occurrence characteristics curve that records of experiment or storage of processor 11, control system also comprises storage battery 13, storage battery 13 is for powering to control unit 9, and storage battery 13 is also used to frequency variator 8 to drive piezoelectric chip 18 vibrations that power is provided.
The temperature information of the motor 1 that the control unit 9 of the present embodiment detects can characterize near state of temperature active silencer 5 indirectly, so just can be separately again mounting temperature sensor test, this temperature information comprises at least one output signal of the cooling water temperature, oil temperature or the lambda probe that receive from motor 1.
Above the utility model is described in detail; its object is to allow the personage who is familiar with this art can understand content of the present utility model and be implemented; can not limit protection domain of the present utility model with this; all equivalences of doing according to Spirit Essence of the present utility model change or modify, and all should be encompassed in protection domain of the present utility model.
Claims (8)
1. the active noise controlling system for automobile exhaust system, comprise the outlet pipe on the motor that is connected to described automobile, the control system that is connected to the ternary catalyzing unit between described motor and the tail pipe of described outlet pipe and is electrically connected with described motor, it is characterized in that, described active noise controlling system also comprises the active silencer being connected between described ternary catalyzing unit and described tail pipe, described active silencer has vibrating plate, the control signal of described control system output transfers to described active silencer and eliminates Middle and low frequency noise for the anti-sound of generation of vibration of controlling described vibrating plate, described Middle and low frequency noise is the noise of frequency at 0～1000Hz.
2. active noise controlling system according to claim 1, it is characterized in that, described active silencer comprises housing, described vibrating plate is fixedly installed in described housing and described housing is separated into the first chamber and the second chamber, described active silencer also comprises and is arranged on the piezoelectric chip being connected on described vibrating plate and with described control system, the control signal control that described piezoelectric chip is exported by described control system produces vibration, the radiated noise that the vibration of described piezoelectric chip drives described vibration plate vibrates to produce corresponding frequencies and phase place is eliminated described Middle and low frequency noise.
3. active noise controlling system according to claim 2, it is characterized in that, described active silencer also comprises the suction tude and the steam outlet pipe that are fixedly installed on described housing two ends, one end of described suction tude is positioned at outside described housing and is connected with described outlet pipe, and the other end of described suction tude is through straight-through described the second chamber of described the first chamber; One end of described steam outlet pipe is positioned at outside described housing and is connected with described tail pipe, and the other end of described steam outlet pipe is connected on described housing and with described the second chamber and is communicated with.
4. active noise controlling system according to claim 3, it is characterized in that, described active silencer also comprises the filter screen being fixedly installed in described the second chamber, and described filter screen is for filtering the particle of tail exhaust body, and the other end of described suction tude is through described filter screen.
5. active noise controlling system according to claim 2, it is characterized in that, on described vibrating plate, evenly arrange and offer the multiple air holes for the first chamber described in balance and described the second chamber pressure along the circumferencial direction of described vibrating plate, described the first chamber and described the second chamber are only connected by described air hole.
6. active noise controlling system according to claim 2, it is characterized in that, described control system comprises the control unit being electrically connected with described motor, be electrically connected with described control unit and can be arranged in the error microphone of described active silencer rear end and be connected to described control unit and described active silencer between frequency variator, described frequency variator is electrically connected with described control unit and described piezoelectric chip respectively, described frequency variator receives the control signal of described control unit output, then the radiated noise that drives described vibration plate vibrates to produce corresponding frequencies and phase place for controlling the vibration of described piezoelectric chip is eliminated described Middle and low frequency noise, described error microphone and guides control signal described in described control unit correction for the soundproof effect of active silencer described in Real-time Feedback.
7. active noise controlling system according to claim 6, it is characterized in that, described control unit comprises the control chip, processor and the storage that integrate, and described control chip produces the anti-acoustic signal of corresponding frequencies and phase place for frequency variator described in the feedback signal of feeding back according to described error microphone or the described engine behavior SC sigmal control of feeding back by described motor; Described processor is used for processing in real time the primary signal of described error microphone or described motor feedback, and result of calculation is fed back to described control chip; Described storage is tested the original occurrence characteristics curve recording or is stored the real-time control data that described processor calculates for storing, described control system also comprises storage battery, described storage battery is for to the power supply of described control unit, and described storage battery is also used to piezoelectric chip vibration described in described transducer drive that power is provided.
8. active noise controlling system according to claim 1, it is characterized in that, between described ternary catalyzing unit and described active silencer, be also provided with dissipative muffler, described dissipative muffler is for passive elimination high frequency noise, and described high frequency noise is the noise of frequency more than 1000Hz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420287385.XU CN203867673U (en) | 2014-05-30 | 2014-05-30 | Active noise control system used for automobile exhaust system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420287385.XU CN203867673U (en) | 2014-05-30 | 2014-05-30 | Active noise control system used for automobile exhaust system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203867673U true CN203867673U (en) | 2014-10-08 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420287385.XU Withdrawn - After Issue CN203867673U (en) | 2014-05-30 | 2014-05-30 | Active noise control system used for automobile exhaust system |
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| Country | Link |
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| CN (1) | CN203867673U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103982281A (en) * | 2014-05-30 | 2014-08-13 | 清华大学苏州汽车研究院（相城） | Active noise control system and method for automobile exhaust system |
| CN107071637A (en) * | 2016-01-14 | 2017-08-18 | 佛吉亚排放控制技术德国有限公司 | For the audio system of the method, the gas extraction system of engine and passenger's unit of the loudspeaker generation drive signal of arrangement in a motor vehicle |
-
2014
- 2014-05-30 CN CN201420287385.XU patent/CN203867673U/en not_active Withdrawn - After Issue
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103982281A (en) * | 2014-05-30 | 2014-08-13 | 清华大学苏州汽车研究院（相城） | Active noise control system and method for automobile exhaust system |
| CN107071637A (en) * | 2016-01-14 | 2017-08-18 | 佛吉亚排放控制技术德国有限公司 | For the audio system of the method, the gas extraction system of engine and passenger's unit of the loudspeaker generation drive signal of arrangement in a motor vehicle |
| CN107071637B (en) * | 2016-01-14 | 2021-04-23 | 佛吉亚排放控制技术德国有限公司 | Method for generating a drive signal for a loudspeaker arranged in a motor vehicle, exhaust system of an engine and sound system of a passenger unit |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20141008 Effective date of abandoning: 20160427 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |