CN104895848B - The autologous active noise reduction system of fan - Google Patents
The autologous active noise reduction system of fan Download PDFInfo
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- CN104895848B CN104895848B CN201410080426.2A CN201410080426A CN104895848B CN 104895848 B CN104895848 B CN 104895848B CN 201410080426 A CN201410080426 A CN 201410080426A CN 104895848 B CN104895848 B CN 104895848B
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Abstract
The present invention is a kind of autologous active noise reduction system of fan, it includes fan, promotion group, at least a radio unit and a digital signals processing unit, the digital signals processing unit is sent to through the Shou sound Dan Yuan Screenshot noises for taking the fan to produce, the digital signals processing unit is made to do output control signal after calculation process according to the noise input signal of reception, to control the propelling coil group start, and then promote the impeller upper and lower displacement of the fan, and produce reverse sound wave, with offset noise, the effect person for reaching the autologous active noise reduction of fan is used.
Description
【Technical field】
The present invention is related to a kind of fan system, it is espespecially a kind of have through the autologous effect for actively reaching noise reduction of fan and
The cost-effective autologous active noise reduction system of fan.
【Background technology】
Because computer has been the electronic installation that today, people commonly used, and most of computers will handle the data of many daily
Computing, however processing data it is more when, CPU (Central Processing Unit, abbreviation CPU) must in computer
Hyperpyrexia can be produced so that cause CPU running unstable, computer is produced misoperation, or even generation computer is worked as
Machine phenomenon, and then can burn the electronic component of computer internal work when serious.So general industry is all to Using the fan to carry out
To electronic component (such as CPU, drawing chip or north and south bridge chip) forced heat radiation, allow the computer can be steady in running
It is fixed, though the problem of being radiated in fan settlement computer, but extend another problem, it is exactly that fan can be produced when running and made an uproar
The problem of vocal cores is to perplex.
And the noise problem produced by fan, make dealer by suitable attention, because noise can make one to produce different journeys
The uneasiness and Anxiety of degree, increase tired degree, reduce task performance, psychological and physiological injury can be caused what is more, so, have
Abating the noise not only to effect is academicly having its meaning, industrially great practical value, and to the improvement in daily life
It is very helpful.The general active noise control of fan at present is to capture fan through one or more radio reception microphones to produce
Noise, and produce a noise input signal send to a digital signals microprocessor (Digital Signal Processor,
Abbreviation DSP), make the digital signals microprocessor be done according to the noise input signal of reception after calculation process, the control news of output one
Number send on one or more loudspeakers of connection and drive, make aforementioned speakers send reverse sound wave (or reversely source of sound)
With offset noise.
Although the active noise control of fan can reach the effect of offset noise, it extends another problem, just
It is the not single noise captured to fan at foregoing radio reception microphone, while also having the reverse sound that loudspeaker is sent
Come from environment space and reflect, and it is superimposed with noise in environment space so that and what the digital signals microprocessor was received makes an uproar
Sound input signal contains the noise of fan and the noise being superimposed in environment space and reflection source of sound, has caused to do computing complexity
High and produced reverse source of sound can not effectively offset noise and the noise being superimposed in environment space and the reflection of fan generation
Source of sound, so that cause that noise reduction is not good and cost of equipment is expensive, therefore the active noise control of known fan can only offset receipts
Sound microphone places the noise of position that point so that how dealer is still overcome in this technology in positive effort at present
The problem of.
The above is known with following shortcoming：
1. noise reduction is not good.
2. apparatus expensive high cost.
How the above-mentioned problem commonly used and missing, the as inventor of this case relevant manufactures be engaged in the industry are solved
The direction place person for desiring most ardently research improvement.
【The content of the invention】
Therefore, it is that the problem of effectively solving above-mentioned, the main purpose of the present invention is providing a kind of with preferable noise reduction
The autologous active noise reduction system of fan.
Another object of the present invention provide it is a kind of have reduce the autologous active noise reduction system of fan of cost.
In order to which up to above-mentioned purpose, the present invention provides a kind of autologous active noise reduction system of fan, including：Fan, includes frame
Body, axle bed and impeller, the impeller have magnetic axle center and plural blade, and the one end in the magnetic axle center is fixedly arranged on the center of the impeller
Place, the framework has one to be installed with space, and the axle bed is arranged on the centre in the accommodation space, and has in axis hole, the axis hole
An at least bearing is installed with, the bearing and the other end in relative magnetic axle center are mutually pivoted；Promotion group, it has a propelling coil
Group, the propelling coil group is located in the axis hole, and adjacent bearing and excitatory with relative magnetic axle center sensing, so that promote should
The axial direction upper and lower displacement of magnetic axle center, makes the impeller produce reverse sound wave, to offset the noise of fan generation；An at least radio reception list
Member, in the framework, it and produces noise input signal according to the noise that the fan is produced is captured；And digital signals processing
Unit, its one end is electrically connected with the radio unit, and its other end is then electrically connected with the propelling coil group, and digital signals processing is single
Member does output one after calculation process according to the noise input signal of reception and controls signal, to control the propelling coil group start.
Through the design of the autologous active noise reduction system of this fan of the invention, obtain and effectively reach preferable noise reduction and reduction
The effect person of cost.
The digital signals processing unit is included：Digital signals microprocessor, pre-amplifier, post-amplifier, analogy turn
Digital converter and numerical digit turn analogy converter, and pre-amplifier is electrically connected the radio unit and changed with class specific revolution position
Device, the digital signals processor is electrically connected such specific revolution bit pad and turns analogy converter, rear class amplification with numerical digit
Device is electrically connected the numerical digit and turns analogy converter and propelling coil group.
The radio unit is radio reception microphone, and the radio unit is arranged on the top of the framework and the relative impeller.
The magnetic axle center has the first magnetic pole and the second magnetic pole, and first magnetic pole is located at the adjacent propelling coil group one end
On magnetic axle center, second magnetic pole is located on the magnetic axle center of the adjacent propelling coil group other end.
The axle bed has supporting part, and the center of the supporting part from axle bed inwall towards the axis hole protrudes out composition, and it is provided with
First platform and the second platform, first platform formation is at the top of the supporting part, and second platform is then formed in the supporting part
Bottom, and the grade bearing has clutch shaft bearing and second bearing, and the clutch shaft bearing is placed on the first relative platform, and this
Two bearings are placed on the second relative platform.
The other end outer concave in the magnetic axle center is provided with a groove, and the groove is located at relative second bearing lower section, its
Fixed with for a fixture sandwiched, and a displacement space is defined between the groove and relative second bearing.
The fan further includes a controller, and the controller is electrically connected with foregoing digital signals processing unit, and it is to transmit
One rotational frequency signal gives the digital signals processing unit, makes the digital signals processing unit according to the reception rotational frequency signal
Phase be reference point, to adjust the phase of noise input signal and do calculation process, and export another control signal, with control
The propelling coil group start.
The present invention separately provides a kind of fan autologous active noise reduction system, including：Fan, includes framework, axle bed and a fan
Wheel, the impeller has axle center and plural blade, and the one end in the axle center is fixedly arranged on the centre of the impeller, and the framework has one to be installed with
Space, the axle bed is arranged on the centre in the accommodation space, and with an axis hole, the axis hole content is provided with an at least bearing,
The bearing and the other end in relative axle center are mutually pivoted；Promotion group, it has housing, propelling coil group and magnetic part, the housing
The bottom of the axle bed is butted up against, and it is provided with the relative accommodation space for connecting the axis hole, the accommodation space content is provided with the promotion
Coil group and magnetic part, and the other end in the relative axle center of magnetic part one end connection, and with to should propelling coil group sense
It is excitatory, to promote the axial upper and lower displacement in the axle center, make the impeller produce reverse sound wave, to offset the noise of fan generation；Extremely
A few radio unit, in the framework, it produces noise input signal according to capturing the noise that the fan is produced；And number
Position signal processing unit, its one end is electrically connected with the radio unit, and its other end is then electrically connected with the propelling coil group, the numerical digit
Signal processing unit does output control signal after calculation process according to the noise input signal of reception, to control the propelling coil group
Start.
Through the design of the autologous active noise reduction system of this fan of the invention, obtain and effectively reach preferable noise reduction and reduction
The effect person of cost.
The digital signals processing unit is included：Digital signals microprocessor, pre-amplifier, post-amplifier, analogy turn
Digital converter and numerical digit turn analogy converter, and pre-amplifier is electrically connected the radio unit and changed with class specific revolution position
Device, the digital signals processor is electrically connected such specific revolution bit pad and turns analogy converter, rear class amplification with numerical digit
Device is electrically connected the numerical digit and turns analogy converter and propelling coil group.
The radio unit is radio reception microphone, and the radio unit is arranged on the top of the framework and the relative impeller.
The magnetic part is magnet, and the magnetic part has the first magnetic pole and one second magnetic pole, and first magnetic pole is located at the magnetic
On one end of part, and the other end in the adjacent axle center, second magnetic pole is located on the other end of the magnetic part, and the adjacent housing
Interior bottom side.
The axle bed has supporting part, and the center of the supporting part from axle bed inwall towards the axis hole protrudes out composition, and it is provided with
First platform and the second platform, first platform formation is at the top of the supporting part, and second platform is then formed in the supporting part
Bottom, and the grade bearing has clutch shaft bearing and second bearing, and the clutch shaft bearing is placed on the first relative platform, and this
Two bearings are placed on the second relative platform.
The other end outer concave in the magnetic axle center is provided with groove, and the groove is located at relative second bearing lower section, and it is used
So that a fixture sandwiched is fixed, and a displacement space is defined between the groove and relative second bearing.
The fan further includes controller, and the controller is electrically connected with foregoing digital signals processing unit, and it is to transmit one
Rotational frequency signal gives the digital signals processing unit, makes the digital signals processing unit according to receiving the rotational frequency signal
Phase is reference point, to adjust the phase of noise input signal and do calculation process, and exports another control signal, to control to be somebody's turn to do
Propelling coil group start.
【Brief description of the drawings】
The combination schematic perspective view of Fig. 1 the first preferred embodiments of the present invention.
The exploded perspective schematic diagram of Fig. 2 the first preferred embodiments of the present invention.
The block schematic diagram of Fig. 3 the first preferred embodiments of the present invention.
The combination diagrammatic cross-section of Fig. 4 A the first preferred embodiments of the present invention.
Another combination diagrammatic cross-section of Fig. 4 B the first preferred embodiments of the present invention.
Another combination diagrammatic cross-section of Fig. 4 C the first preferred embodiments of the present invention.
The block schematic diagram of Fig. 5 the second preferred embodiments of the present invention.
The combination schematic perspective view of Fig. 6 the 3rd preferred embodiments of the present invention.
The exploded perspective schematic diagram of Fig. 7 the 3rd preferred embodiments of the present invention.
The block schematic diagram of Fig. 8 the 3rd preferred embodiments of the present invention.
The combination diagrammatic cross-section of Fig. 9 A the 3rd preferred embodiments of the present invention.
Another combination diagrammatic cross-section of Fig. 9 B the 3rd preferred embodiments of the present invention.
Another combination diagrammatic cross-section of Fig. 9 C the 3rd preferred embodiments of the present invention.
The block schematic diagram of Figure 10 the 4th preferred embodiments of the present invention.
The corresponding component name of each reference is in figure：
The autologous active noise reduction system ... 1,2 of fan
Fan ... 10,20
Framework ... 101,201
It is installed with space ... 1011,2011
Axle bed ... 102,202
Supporting part ... 1021,2021
First platform ... 10211,20211
Second platform ... 10212,20212
Axis hole ... 1023,2023
Impeller ... 103,203
Magnetic axle center ... 1031
Groove ... 10311,20311
First magnetic pole ... 10313
Second magnetic pole ... 10314
Axle center ... 2031
Blade ... 1032,2032
Bearing ... 104,204
Clutch shaft bearing ... 1041,2041
Second bearing ... 1042,2042
Displacement space ... 105,205
Circuit board ... 106,206
Stator ... 107,207
Silicon steel sheet group ... 1071,2071
Coil group ... 1072,2072
Magnet ... 108,208
Controller ... 109,209
Promotion group ... 13,23
Propelling coil group ... 131,231
Housing ... 232
Accommodation space ... 2321
Magnetic part ... 234
First magnetic pole ... 2341
Second magnetic pole ... 2342
Radio unit ... 15,26
Digital signals processing unit ... 16,27
Digital signals microprocessor ... 161,271
Pre-amplifier ... 162,272
Post-amplifier ... 163,273
Class specific revolution bit pad ... 164,274
Numerical digit turns analogy converter ... 165,275
Fixture 3
【Embodiment】
Above-mentioned purpose and its structure of the present invention and characteristic functionally, will be said according to the preferred embodiment of institute's accompanying drawings
It is bright.
The present invention provides a kind of autologous active noise reduction system of fan, refers to Fig. 1,2,3 and shows, and the first of the display present invention
The solid and block schematic diagram of preferred embodiment, and be aided with and show refering to Fig. 4 A；The autologous active noise reduction system 1 of the fan includes wind
Fan 10, at least promotion group 13, a radio unit 15 and digital signals processing unit 16, the fan 10 include framework 101, axle bed
102nd, impeller 103, stator 107 and control chip (not shown), control chip (such as microprocessor, MCU) are arranged on the axle bed
On the circuit board 106 that the side of 102 relative impellers 103 has, the control chip, should to control fan 10 to operate and rotating speed
Stator 107 is sheathed on the outside of the axle bed 102, and the magnet 108 having in the relative impeller 103, and the stator 107 has
The coil group 108 for having a silicon steel sheet group 1071 and being wound in silicon steel sheet group 1071.
Foregoing impeller 103 has a magnetic axle center 1031 and plural blade 1032, and the one end in the magnetic axle center 1031 is fixed
In the centre of the relative impeller 103, its other end outer concave is provided with groove 10311, and the groove 10311 is with for fixture 3
(such as c-type clasp) sandwiched is fixed.The framework 101, which has, is installed with space 1011, and the axle bed 102 is arranged on this and is installed with space 1011
Interior centre, and it has and connects this and be installed with the axis hole 1023 and supporting part 1021 in space 1011, the supporting part 1021 from this
The center of the inwall of axle bed 102 towards the axis hole 1023 protrudes out composition, and it is provided with the first platform 10211 and the second platform 10212, should
First platform 10211 forms the top in the supporting part 1021, and second platform 10212 then forms the bottom in the supporting part 1021
Portion.
And the foregoing content of axis hole 1023 is provided with an at least bearing 104, the bearing 104 is another with relative magnetic axle center 1031
One end is mutually pivoted, and is explained in the bearing 104 of the preferred embodiment with 2 bearings, that is, the grade bearing 104 has first axle
1041 and second bearing 1042 are held, the clutch shaft bearing 1041 is placed on the first relative platform 10211, the second bearing
1042 are placed on relative second platform 10212, and it is located to should change at the top of groove 10311 in magnetic axle center 1031
Yan Zhi, is exactly that the groove 10311 is located at the lower section of relatively foregoing second bearing 1042.And the groove 10311 with it is relative
A displacement space 105 is defined between second bearing 1042, the displacement space 105 is with for the axial upper and lower displacement in magnetic axle center 1031
Activity space.
Continuous refering to shown in Fig. 2,3,4A, foregoing promotion group 13 has a propelling coil group 131, and the propelling coil group 131 is held
In axis hole 1023, and adjacent aforementioned bearings 104 and excitatory, that is, the propelling coil is sensed with relative magnetic axle center 1031
Group 131 is located between first and second bearings 1041,1042 in the axis hole 1023, and have with respect to the magnetic axle center 1031
One first magnetic pole 10313 and one second magnetic pole 10314, in first and second magnetic pole 10313,10314 compared with embodiment respectively with N
Pole is explained with S poles, but Bing Bu Authority are limited to this, when specific implementation, also may be designed as first and second magnetic pole 10313,10314
Respectively S poles and N poles.
So making that during foregoing 131 energization start of propelling coil group magnetic field can be produced, first and second magnetic with magnetic axle center 1031
The magnetic force mutual repulsion effect of pole (i.e. N poles and S poles), and promote the magnetic axle center 1031 in operating in displacement space 105 axially
Upper and lower displacement (as refering to shown in Fig. 4 A, 4B, 4C), while the impeller 103 in order operating provides air quantity, can also produce one anti-
To sound wave, the wherein reverse sound wave is sound wave identical and opposite in phase with the amplitude size of the noise of the generation of fan 10, and this is anti-
To sound wave to interfere or offset the running noise of impeller 103.Wherein in first magnetic in the magnetic axle center 1031 of the preferred embodiment
Pole 10313 (i.e. N poles) is located on the magnetic axle center 1031 of one end of the adjacent propelling coil group 131, and the second magnetic pole 10314
(i.e. S poles), which is located on the magnetic axle center 1031 of the other end of the adjacent propelling coil group 131, to be explained, but Bing Bu Authority are limited to this；
When specific implementation, the magnetic in the magnetic axle center 1031 also may be designed as the second magnetic pole 10314 positioned at the adjacent propelling coil
On the magnetic axle center 1031 of 131 one end of group, and the first magnetic pole 10313 is located at the magnetic of the other end of the adjacent propelling coil group 131
On property axle center 1031.
So by the present invention fan 10 it is autologous be sound generation source, in foregoing impeller 103 produce noise while, immediately thoroughly
The autologous reverse sound wave of generation of the fan 10 is crossed, with effectively interference or offset noise, and then also effectively prevent the noise source of sound of fan 10
Reflection is produced in environment space and complicated noise source of sound is formed, therefore so that noise amplitude and suppression effectively is greatly reduced ahead of time
The effect of the diverging of noise, and then because the signal source (i.e. noise source of sound) that digital signals processing unit 16 is received is relatively easy,
Make it low in calculation process complexity, use and effectively reach cheap effect.
Foregoing radio unit 15 is a radio reception microphone, its in the framework 101 and the relative impeller 103, in this compared with
The radio reception microphone of good embodiment is installed on the top of the framework 101, and the relative impeller 103, and it (or is read according to capturing
Take) noise that is produced in operating of the impeller 103 of the fan 10, and produce noise input signal and send at foregoing digital signals
Manage unit 16, and the digital signals processing unit 16 in the preferred embodiment to be arranged on the bottom of the adjacent framework 101, and should
Fan 10 further includes one to control rotation speed of the fan and the controller of operating 109, and the controller 109, should on circuit board 106
Circuit board 106 is arranged on the side of the relative impeller 103 of the axle bed 102 and explained, that is, the digital signals processing unit 16 is only
Vertical calculation process noise signal simultaneously controls the start of promotion group 13, the controller of the fan 10 then independent control fan 10 operate and
Rotating speed.
And when specific implementation, foregoing digital signals processing unit 16 also can with the controller of fan 10 (such as microprocessor,
MCU) design integration makes the operation independent of digital signals processing unit 16 handle noise signal and control on same circuit board 106
The start of promotion group 13 processed, then independent control fan 10 is operated and rotating speed the control chip of the fan 10, or another specific reality
Shi Shi, the digital signals processing unit 16 also can be designed directly on the circuit board 106 of the side of the axle bed 102, to replace original
The controller (i.e. the controller of fan-free) of first fan 10, through the micro- place of digital signal of single digital signals processing unit 16
Reason device 161 (Digital Signal Processor, DSP) control fan 10 is operated and rotating speed, and handles noise signal simultaneously
And the start of control promotion group 13, close elder generation Chen Ming.
Refer to shown in Fig. 3,4A, one end of foregoing digital signals processing unit 16 is electrically connected with the radio unit 15, its
The other end is then electrically connected with the propelling coil group 131, and it does according to the noise input signal of reception and exported after calculation process a control
Signal processed, to control the start of propelling coil group 131, such as the propelling coil group 131 receives control signal and is powered and makees movable property
Magnetisation.And the digital signals processing unit 16 includes foregoing digital signals the microprocessor 161, (Pre- of pre-amplifier 162
Amplifier, or pre-stage amplifiers), post-amplifier 163 (Power Amplifier, or power amplifier), class
Specific revolution bit pad 164 (Analogue to Digital Converter, abbreviation ADC) and a numerical digit turn analogy converter
165 (Digital to Analogue Converter, abbreviation DAC).
The pre-amplifier 162 has the characteristic of interference resistant, and its one end is electrically connected with the radio unit 15, its other end
Such specific revolution bit pad 164 is then electrically connected with, and the noise that the pre-amplifier 162 transmits the radio unit 15 is inputted
Signal is done after signal enhanced processing, the noise input signal after output amplification, and foregoing class specific revolution bit pad 164 is according to connecing
Receive the noise input signal after the amplification and be converted to digital signals (the numerical digit noise input signal after amplifying).
And foregoing digital signals microprocessor 161 is electrically connected such specific revolution bit pad 164 and turns class with numerical digit
Than converter 165, it does one reverse digital signals of output after calculation process according to foregoing digital signals is received, and sends this to
Numerical digit turns analogy converter 165, makes the numerical digit turn analogy converter 165 and the reverse digital signals received is converted into reverse class
Compare signal.And the propelling coil that the numerical digit turns analogy converter 165 and promotion group 13 is electrically connected in the post-amplifier 163
Group 131, it is to by the signal power enhanced processing of reception, that is, foregoing post-amplifier 163 is by the reverse analogy of reception
After signal power enhanced processing, output control signal (or being the analogy audio signal after amplification), to control the promotion line
The start of circle group 131.
So when fan 10 is when operating and producing noise, the radio unit 15 is relative in being captured at any time in framework 101
The noise that impeller 103 is sent, and produce noise input signal and send pre-amplifier 162 to, pre-amplifier 162 is by reception
Noise input signal is done after signal enhanced processing, is exported the noise input signal after the amplification and is sent such specific revolution position turn to again
Parallel operation 164, is converted to digital signals by the noise input signal after amplification through class specific revolution bit pad 164 (ADC), makes the number
Position signal microprocessor 161 (DSP) exported after calculation process reverse digital signals according to receiving digital signals and does, and sends to
The numerical digit turns analogy converter 165 (DAC) and reverse digital signals is converted into reverse analog signal, and the post-amplifier
163 by after the reverse analog signal power enhanced processing received, and output control signal sends the propelling coil group to
131, and then control the energization start of propelling coil group 131 to produce magnetic field, it is excitatory to sense with corresponding magnetic axle center 1031, and
Promote the magnetic axle center 1031 of impeller 103 in operating can be in the axial upper and lower displacement in aforementioned displacements space 105 (as refering to the
4A, 4B, 4C are illustrated), the amplitude size phase for the noise that the reverse sound wave for making impeller 103 produce (or sending) is produced with fan 10
Together, but reversely the phase of sound wave is opposite with the phase of foregoing noise, produced with effectively interfering or eliminating fan 10 when operating
Raw noise.
Therefore, through the digital signals processing unit 16 of the present invention in good time control start of promotion group 13, with magnetic
Axle center 1031 senses excitatory, promotes the upper and lower displacement of magnetic axle center 1031, make impeller 103 it is autologous send reverse sound wave offsetting (or
Interference) fan 10 produces the system design of noise, and obtain and effectively reach preferably noise reduction and reduce the effect of cost, and then also
It is prevented effectively from the effect that the noise source of sound of fan 10 produces reflection and the complicated noise source of sound of formation in environment space.
The 5th diagram is referred to, the block schematic diagram of the second preferred embodiment of the present invention is shown, and is aided with refering to the 3rd, 4A
Diagram；The structure of this preferred embodiment and its link are closed and its effect is substantially identical with foregoing first preferred embodiment, therefore
This is not repeated again, both difference be in：The controller 109 of foregoing fan 10 is electrically connected with the digital signals processing unit
16 digital signals microprocessor 161, it is to transmit numerical digit of the rotational frequency signal to the digital signals processing unit 16
Signal microprocessor 161, and foregoing digital signals processing unit 16 according to receive rotational frequency signal phase be reference point,
To adjust the phase of noise input signal and do calculation process, and another control signal is exported, to control the propelling coil group 131
Start.
Wherein the rotational frequency signal (or being FG (Frequency Generator) signal) is the rotating speed for representing fan
Signal, and the frequency of the noise produced in the actually fan 10 is identical with the frequency of rotational frequency signal (or synchronization), and
Due to having distance between radio unit 15 and blade 1032, the radio unit 15 is made to be had when receiving the noise of the generation of fan 10
Delay, therefore send the digital signals microprocessor (DSP) 161 of the digital signals processing unit 16 to through the rotational frequency signal
It is as a reference point, the digital signals microprocessor 161 is suitably postponed the phase of the digital signals of reception according to reference point and is done
Calculation process, and export another reverse digital signals being same as with the phase difference 180 degree of noise sound wave, such as described numerical digit news
Number microprocessor 161 is reference point according to the phase of the rotational frequency signal is received, to adjust the numerical digit actually received news
Number (i.e. noise input signal) and 175 degree of the phase difference of noise are deferred to phase difference equal to (or close to) 180 degree and do computing
Processing, and export and be same as (or close to) and another reverse digital signals of the phase difference 180 degree of noise sound wave.
So when fan 10 is when operating and producing noise, the radio unit 15 is relative in being captured at any time in framework 101
The noise that impeller 103 is sent, and produce foregoing noise input signal and send pre-amplifier 162 to, pre-amplifier 162 will connect
The noise input signal of receipts is done after signal enhanced processing, is exported the noise input signal after the amplification and is sent such specific revolution to again
Bit pad 164, digital signals is converted to through class specific revolution bit pad 164 (ADC) by the noise input signal after amplification, this
Shi Suoshu digital signalses microprocessor (DSP) 161 can receive rotational frequency signal and digital signals simultaneously, and according to receiving
The phase of rotational frequency signal be reference point, with adjust receive digital signals (amplify after numerical digit noise input signal) it
Phase delay is simultaneously done after calculation process, is exported another reverse digital signals, and is sent the numerical digit to and turns analogy converter 165
(DAC) another reverse digital signals is converted into another reverse analog signal, and the post-amplifier 163 is then another by what is received
After one reverse analog signal power enhanced processing, and export another control signal and send the propelling coil group 131 to, and then control
Make the energization start of propelling coil group 131 and produce magnetic field, it is excitatory to sense with corresponding magnetic axle center 1031, and promote in operating
In the magnetic axle center 1031 of impeller 103 can be in the axial upper and lower displacement in aforementioned displacements space 105 (as referred to Fig. 4 A, 4B, 4C institute
Show), making impeller 103 produce (or sending), reversely sound wave is identical with the amplitude size for the noise that fan 10 is produced, but reversely sound wave
Phase be opposite with the phase of foregoing noise, effectively to interfere or eliminate the noise that fan 10 is produced when operating.
In addition, if fan 10 is when the noise that operating is produced is eliminated, it is defeated that the radio unit 15 can almost can not receive noise
Enter signal, the digital signals for receiving the digital signals microprocessor 161 also can be very faint, and then the rotational frequency received
Signal will be main reference signal and do operating processing, and export another reverse signal of frequency identical with noise, use
Reach the effect for maintaining payment noise.
Therefore the rotational frequency signal of the transmission of controller 109 of the transmission present invention is reference point to digital signals processing unit 16
With using the design of the phase of appropriate delay digit signal so that effectively reach smart Quasi interference or eliminate fan 10 when operating
The noise of generation.
Refer to shown in Fig. 6,7,8, show the solid and block schematic diagram of the 3rd preferred embodiment of the present invention, and be aided with
Refering to shown in Fig. 9 A；The autologous active noise reduction system 2 of the fan include fan 20, promotion group 23, an at least radio unit 26 and
Digital signals processing unit 27, the fan 20 includes framework 201, axle bed 202, impeller 203, stator 207 and control chip, control
Chip (such as microprocessor, MCU) is arranged on the circuit board 206 that the axle bed 202 has with respect to the side of impeller 203, and it is used to
Control fan 20 is operated and rotating speed, and the stator 207 is sheathed on the outside of the axle bed 202, and have in the relative impeller 203
Magnet 208, and the stator 207 has a silicon steel sheet group 2071 and the coil group 208 being wound in silicon steel sheet group 2071.
Foregoing impeller 203 has an axle center 2031 and plural blade 2032, and the one end in the axle center 2031 is fixedly arranged on relative be somebody's turn to do
The centre of impeller 203, its other end outer concave is provided with groove 20311, and the groove 20311 is with for (such as c-type button of fixture 3
Ring) sandwiched fixes.The framework 201, which has, one is installed with space 2011, and the axle bed 202 is arranged on during this is installed with space 2011
At centre, and it has a connection this is installed with the supporting part 2021 of axis hole 2023 and one in space 2011, and the supporting part 2021 is from the axle
The center of seat 202 inwalls towards the axis hole 2023 protrudes out compositions, and it is provided with the first platform 20211 and the second platform 20212, and this
One platform 20211 forms the top in the supporting part 2021, and second platform 20212 then forms the bottom in the supporting part 2021
Portion.
And foregoing axis hole 2023 runs through from the top of the axle bed 202 towards its bottom, and its content is provided with an at least bearing
204, the bearing 204 and the other end in relative axle center 2031 are mutually pivoted, and in the preferred embodiment bearing 204 with 2 axles
Explanation is made, that is, the grade bearing 204 has clutch shaft bearing 2041 and second bearing 2042, the clutch shaft bearing 2041 is placed on this
On the first relative platform 20211, the second bearing 2042 is placed on relative second platform 20212, and it is located at respective shaft
It is exactly that the groove 20311 is located under relatively foregoing second bearing 2042 in other words at the top of groove 20311 of the heart 2031
At side.And displacement space 205 is defined between the groove 20311 and relative second bearing 2042, the displacement space 205 is with for axle
The activity space of the axial upper and lower displacement of the heart 2031.
It is continuous that refering to shown in Fig. 7,8,9A, foregoing promotion group 23 has housing 232, propelling coil group 231 and magnetic part 234,
The housing 232 is butted up against on the bottom of the axle bed 202, and it is provided with accommodation space 2321, the accommodation space 2321 connection correspondence
Axis hole 2023, and its content be provided with the propelling coil group 231 and magnetic part 234, the magnetic part 234 be magnet, the magnetic
One end connection of part 234 is through the other end in the axle center 2031 of the axle bed 202 its upper bottom portion, and be located at should for foregoing magnetic part 234
At the lower section of second bearing 2042, and with to should propelling coil group 231 sense it is excitatory, that is, in the accommodation space 2321
Propelling coil group 231 is located between the magnetic part 234 and the madial wall of housing 232, and the first magnetic that relative magnetism part 234 has
The magnetic pole 2342 of pole 2341 and second, so making that during foregoing 231 energization start of propelling coil group magnetic field can be produced, with magnetic part 234
First and second magnetic pole 2341,2342 (i.e. N poles and S poles) magnetic force mutual repulsion effect, and promote the axle center 2031 in operating can be in
The axial upper and lower displacement of displacement space 205 (as refering to shown in Fig. 9 A, 9B, 9C), the impeller 203 in order operating provides the same of air quantity
When, a reverse sound wave can be also produced, the wherein reverse sound wave is and phase identical with the amplitude size of the noise of the generation of fan 20
Opposite sound wave, the reverse sound wave is to interfere or offset the running noise of impeller 203.Wherein in the magnetic part of the preferred embodiment
234 the first magnetic pole 2341 (i.e. N poles) is located on one end of magnetic part 234 and relative second bearing 2042, and the second magnetic pole
2342 (i.e. S poles) are located on the other end of the magnetic part 234, and the bottom side in the adjacent housing 232 is explained, but Bing Bu Authority
It is limited to this；When specific implementation, the magnetic of the magnetic part 234 also may be designed as the second magnetic pole 2342 positioned at magnetic part 234
It is located on one end and with respect to second bearing 2042, and the first magnetic pole 2341 on the other end of the magnetic part 234, and the adjacent housing
Bottom side in 232.
So by the present invention fan 20 it is autologous be sound generation source, in foregoing impeller 203 produce noise while, immediately thoroughly
The autologous reverse sound wave of generation of the fan 20 is crossed, with effectively interference or offset noise, and then also effectively prevent the noise source of sound of fan 20
Reflection is produced in environment space and complicated noise source of sound is formed, therefore so that noise amplitude and suppression effectively is greatly reduced ahead of time
The effect of the diverging of noise, and then because the signal source (i.e. noise source of sound) that digital signals processing unit 27 is received is relatively easy,
Make it low in calculation process complexity, use and effectively reach cheap effect.
Foregoing radio unit 26 be radio reception microphone, in this preferably implementations radio unit 26 structure and link pass and
Its effect is identical with foregoing first preferred embodiment, is all the impeller 203 for capturing (or read) fan 20 in operating
The noise of generation, therefore be not described in detail again herein.And included in the digital signals processing unit 27 of this preferred embodiment
Digital signals microprocessor 271 (DSP), pre-amplifier 272 (Pre-Amplifier), (Power of post-amplifier 273
Amplifier), class specific revolution bit pad 274 (ADC) and numerical digit turn each component structure and the company of analogy converter 275 (DAC)
(i.e. digital signals is micro- for the digital signals processing unit 16 and its interior each element of getting customs clearance and its effect and foregoing first preferred embodiment
Processor 161, pre-amplifier 162, post-amplifier 163, class specific revolution bit pad 164 and numerical digit turn analogy converter
165) it is identical, therefore do not repeat again herein, close elder generation Chen Ming.
In addition, when specific implementation, the digital signals processing unit 27 of the preferred embodiment and the controller 209 of fan 20
The collocation design mode of (such as microprocessor, MCU) is identical with foregoing first preferred embodiment, therefore does not repeat again herein.
So when fan 20 is when operating and producing noise, the radio unit 26 is relative in being captured at any time in framework 201
The noise that impeller 203 is sent, and produce noise input signal and send pre-amplifier 272 to, pre-amplifier 272 is by reception
Noise input signal is done after signal enhanced processing, is exported the noise input signal after the amplification and is sent such specific revolution position turn to again
Parallel operation 274, is converted to digital signals by the noise input signal after amplification through class specific revolution bit pad 274 (ADC), makes the number
Position signal microprocessor 271 (DSP) exported after calculation process reverse digital signals according to receiving digital signals and does, and sends to
The numerical digit turns analogy converter 275 (DAC) and reverse digital signals is converted into reverse analog signal, and the post-amplifier
273 by after the reverse analog signal power enhanced processing received, and output control signal sends the propelling coil group to
231, and then control the energization start of propelling coil group 231 to produce magnetic field, it is excitatory to sense with corresponding magnetic part 234, and push away
The axle center 2031 for moving the impeller 203 in operating can be in the axial upper and lower displacement in aforementioned displacements space 205 (as referred to 9A, 9B, 9C
Diagram), make impeller 203 produce (or sending) reverse sound wave it is identical with the amplitude size for the noise that fan 20 is produced, but reversely
The phase of sound wave is opposite with the phase of foregoing noise, effectively to interfere or eliminate the noise that fan 20 is produced when operating.
Therefore, through the digital signals processing unit 27 of the present invention in good time control start of propelling coil group 231, with
Magnetic part 234 senses excitatory, promotes the upper and lower displacement of axle center 2031, and making impeller 203, autologous to send reverse sound wave offsetting (or dry
Relating to) fan 20 produces the system design of noise, and obtain and effectively reach preferably noise reduction and reduce the effect of cost, and then also have
Effect avoids the noise source of sound of fan 20 from producing the effect for reflecting and being formed complicated noise source of sound in environment space.
Refer to shown in Figure 10, show the present invention the 4th preferred embodiment block schematic diagram, and be aided with refering to Fig. 8,
Shown in 9A；The structure of this preferred embodiment and its link are closed and its effect is substantially identical with foregoing 3rd preferred embodiment, therefore
Do not repeat again herein, both difference be in：It is single that the controller 209 of foregoing fan 20 is electrically connected with digital signals processing
The digital signals microprocessor 271 of member 27, it is to transmit numerical digit of the rotational frequency signal to the digital signals processing unit 27
Signal microprocessor 271, and foregoing digital signals processing unit 27 according to receive rotational frequency signal phase be reference point,
To adjust the phase of noise input signal and do calculation process, and another control signal is exported, to control the propelling coil group 231
Start.
Wherein the rotational frequency signal (or being FG (Frequency Generator) signal) is the rotating speed for representing fan
Signal, and the frequency of the noise produced in the actually fan 20 is identical with the frequency of rotational frequency signal (or synchronization), and
Due to having distance between radio unit 26 and blade 2032, the radio unit 26 is made to be had when receiving the noise of the generation of fan 20
Delay, therefore send the digital signals microprocessor (DSP) 271 of the digital signals processing unit 27 to through the rotational frequency signal
It is as a reference point, the digital signals microprocessor 271 is suitably postponed the phase of the digital signals of reception according to reference point and is done
Calculation process, and export another reverse digital signals being same as with the phase difference 180 degree of noise sound wave, such as described numerical digit news
Number microprocessor 271 is reference point according to the phase of the rotational frequency signal is received, to adjust the numerical digit actually received news
Number (i.e. noise input signal) and 175 degree of the phase difference of noise are deferred to phase difference equal to (or close to) 180 degree and do computing
Processing, and export and be same as (or close to) and another reverse digital signals of the phase difference 180 degree of noise sound wave.
So when fan 20 is when operating and producing noise, the radio unit 26 is relative in being captured at any time in framework 201
The noise that impeller 203 is sent, and produce foregoing noise input signal and send pre-amplifier 272 to, pre-amplifier 272 will connect
The noise input signal of receipts is done after signal enhanced processing, is exported the noise input signal after the amplification and is sent such specific revolution to again
Bit pad 274, digital signals is converted to through class specific revolution bit pad (ADC) 274 by the noise input signal after amplification, this
Shi Suoshu digital signalses microprocessor (DSP) 271 can receive rotational frequency signal and digital signals simultaneously, and according to receiving
The phase of rotational frequency signal be reference point, with adjust receive digital signals (amplify after numerical digit noise input signal) it
Phase delay is simultaneously done after calculation process, is exported another reverse digital signals, and is sent the numerical digit to and turns analogy converter (DAC)
Another reverse digital signals is converted to another reverse analog signal by 275, and the post-amplifier 273 is then another by what is received
After reverse analog signal power enhanced processing, and export another control signal and send the propelling coil group 231 to, and then control
The energization start of propelling coil group 231 produces magnetic field, excitatory to sense with corresponding magnetic part 234, and promotes in operating
The axle center 2031 of impeller 203 can make impeller in the axial upper and lower displacement in aforementioned displacements space 205 (as refering to shown in Fig. 9 A, 9B, 9C)
203 produce (or sending), and reversely sound wave is identical with the amplitude size for the noise that fan 20 is produced, but the phase of reverse sound wave and before
The phase for stating noise is opposite, effectively to interfere or eliminate the noise that fan 20 is produced when operating.
In addition, if fan 20 is when the noise that operating is produced is eliminated, it is defeated that the radio unit 26 can almost can not receive noise
Enter signal, the digital signals for receiving the digital signals microprocessor 271 also can be very faint, and then the rotational frequency received
Signal will be main reference signal and do operating processing, and export another reverse signal of frequency identical with noise, use
Reach the effect for maintaining payment noise.
Therefore the rotational frequency signal of the transmission of controller 209 of the transmission present invention is reference point to digital signals processing unit 27
With using the design of the phase of appropriate delay digit signal so that effectively reach smart Quasi interference or eliminate fan 20 when operating
The noise of generation.
Present invention described above has following advantage compared to known：
1. with preferably noise reduction.
2. can effectively prevent that fan noise source of sound from producing reflection in environment space and forming complicated noise source of sound, numerical digit is made to interrogate
Number processing unit is low in calculation process complexity, uses and effectively reaches and reduce the effect of cost.
3. the effect with the diverging that noise amplitude and suppression noise are greatly reduced ahead of time.
Only the above, the only preferably feasible embodiment of the present invention utilizes the above-mentioned method of the present invention, shape such as
Shape, construction, device change for it, should all be contained in the interest field of this case.
Claims (14)
1. a kind of autologous active noise reduction system of fan, it is characterised in that the fan is to include framework, axle bed and impeller, the fan
Wheel is fixedly arranged on the centre of the impeller with magnetic axle center and plural blade, the one end in the magnetic axle center, and the framework, which has, to be installed with
Space, the axle bed is arranged on the centre that this is installed with space, and with axis hole, the axis hole content is provided with an at least bearing, should
Bearing and the other end in relative magnetic axle center are mutually pivoted；
Promotion group, it has propelling coil group, and the propelling coil group is located in the axis hole, and the adjacent bearing and with it is relative
The sensing of magnetic axle center is excitatory, to promote the axial upper and lower displacement in the magnetic axle center, makes the impeller produce reverse sound wave, to offset the wind
Fan the noise produced；
An at least radio unit, in the framework, its according to capture the fan produce noise, and produce noise input news
Number；
Digital signals processing unit, its one end is electrically connected with the radio unit, and its other end is then electrically connected with the propelling coil group,
The digital signals processing unit does output control signal after calculation process according to the noise input signal of reception, to control the promotion
Coil group is acted.
2. the autologous active noise reduction system of fan according to claim 1, it is characterised in that described digital signals processing
Unit is included：Digital signals microprocessor, pre-amplifier, post-amplifier, class specific revolution bit pad sum digit turn analogy
The radio unit and class specific revolution bit pad is electrically connected in converter, pre-amplifier, the digital signals microprocessor
Such specific revolution bit pad is electrically connected and turns analogy converter with numerical digit, the numerical digit is electrically connected in post-amplifier
Turn analogy converter and propelling coil group.
3. the autologous active noise reduction system of fan according to claim 2, it is characterised in that described radio unit is receipts
Sound microphone, the radio unit is located on the top of the framework and is oppositely arranged with the impeller.
4. the autologous active noise reduction system of fan according to claim 3, it is characterised in that described magnetic axle center has
First magnetic pole and the second magnetic pole, first magnetic pole are located on the magnetic axle center of the adjacent propelling coil group one end, second magnetic pole
On the magnetic axle center of the adjacent propelling coil group other end.
5. the autologous active noise reduction system of fan according to claim 4, it is characterised in that described axle bed has support
Portion, the center of the supporting part from axle bed inwall towards the axis hole protrudes out composition, and it is provided with the first platform and the second platform, and this
The formation of one platform is at the top of the supporting part, and second platform is then formed in the bottom of the supporting part, and the bearing has the
One bearing and a second bearing, the clutch shaft bearing are placed on the first relative platform, and the second bearing is placed on relative
On two platforms.
6. the autologous active noise reduction system of fan according to claim 5, it is characterised in that described magnetic axle center it is another
One end outer concave is provided with a groove, and the groove is located at relative second bearing lower section, and it is fixed with for a fixture sandwiched,
And a displacement space is defined between the groove and relative second bearing.
7. the autologous active noise reduction system of fan according to claim 3 or 6, it is characterised in that described fan is more
Comprising controller, the controller is electrically connected with foregoing digital signals processing unit, for transmitting rotational frequency signal to the numerical digit
Signal processing unit, makes the digital signals processing unit according to the phase of the rotational frequency signal is received for reference point, to adjust
The phase of noise input signal simultaneously does calculation process, and exports another control signal, to control the propelling coil group to act.
8. a kind of autologous active noise reduction system of fan, it is characterised in that the fan, includes framework, axle bed and impeller, the impeller
With an axle center and plural blade, the one end in the axle center is fixedly arranged on the centre of the impeller, and the framework has one to be installed with space, should
Axle bed is arranged on the centre that this is installed with space, and with an axis hole, and the axis hole content is provided with an at least bearing, the bearing with
The other end in relative axle center is mutually pivoted；
Promotion group, it has housing, propelling coil group and magnetic part, and the housing butts up against the bottom of the axle bed, and it is provided with one
Connect the axis hole relatively is installed with space, and this is installed with space content and is provided with the propelling coil group and magnetic part, and the magnetic part one
The other end in the relative axle center of end connection, and with to should the sensing of propelling coil group it is excitatory, to promote the axle center axially upper bottom
Shifting makes the impeller produce reverse sound wave, to offset the noise of fan generation；
An at least radio unit, in the framework, the noise produced according to acquisition fan, and produce noise input signal；And
Digital signals processing unit, its one end is electrically connected with the radio unit, and its other end is then electrically connected with the propelling coil group, the number
Position signal processing unit does output control signal after calculation process according to the noise input signal of reception, to control the propelling coil
Group action.
9. the autologous active noise reduction system of fan according to claim 8, it is characterised in that described digital signals processing
Unit is included：Digital signals microprocessor, pre-amplifier, post-amplifier, class specific revolution bit pad and numerical digit turn analogy
The radio unit and class specific revolution bit pad is electrically connected in converter, pre-amplifier, the digital signals microprocessor
Such specific revolution bit pad is electrically connected and turns analogy converter with numerical digit, the numerical digit is electrically connected in post-amplifier
Turn analogy converter and propelling coil group.
10. the autologous active noise reduction system of fan according to claim 8, it is characterised in that described radio unit is
Radio reception microphone, the radio unit is arranged on a top of the framework and the relative impeller.
11. the autologous active noise reduction system of fan according to claim 8, it is characterised in that described magnetic part is magnetic
Iron, the magnetic part has the first magnetic pole and the second magnetic pole, and first magnetic pole is located on one end of the magnetic part, and the adjacent axle center
The other end, second magnetic pole is located on the other end of the magnetic part, and the bottom side in the adjacent housing.
12. the autologous active noise reduction system of fan according to claim 8, it is characterised in that described axle bed has branch
Support part, the center of the supporting part from axle bed inwall towards the axis hole protrudes out composition, and it is provided with the first platform and the second platform, should
The formation of first platform is at the top of the supporting part, and second platform is then formed in the bottom of the supporting part, and the bearing has
Clutch shaft bearing and second bearing, the clutch shaft bearing are placed on the first relative platform, and the second bearing is placed on relative
On two platforms.
13. the autologous active noise reduction system of fan according to claim 12, it is characterised in that the other end in the axle center
Outer concave is provided with a groove, and the groove is located at relative second bearing lower section, and it is fixed with for a fixture sandwiched, and should
A displacement space is defined between groove and relative second bearing.
14. the autologous active noise reduction system of fan according to claim 9 or 12, it is characterised in that described fan is more
Comprising controller, the controller is electrically connected with foregoing digital signals processing unit, and it gives the number to transmit rotational frequency signal
Position signal processing unit, makes the digital signals processing unit according to the phase of the rotational frequency signal is received for reference point, to adjust
The phase of whole noise input signal simultaneously does calculation process, and exports another control signal, to control the propelling coil group to act.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410080426.2A CN104895848B (en) | 2014-03-06 | 2014-03-06 | The autologous active noise reduction system of fan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410080426.2A CN104895848B (en) | 2014-03-06 | 2014-03-06 | The autologous active noise reduction system of fan |
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| CN104895848A CN104895848A (en) | 2015-09-09 |
| CN104895848B true CN104895848B (en) | 2017-07-14 |
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| CN201410080426.2A Active CN104895848B (en) | 2014-03-06 | 2014-03-06 | The autologous active noise reduction system of fan |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114321024B (en) * | 2021-12-31 | 2024-03-26 | 广东美的白色家电技术创新中心有限公司 | Control method and control device of noise reduction device, storage medium and noise reduction device |
| CN114704497A (en) * | 2022-03-14 | 2022-07-05 | 桂林智神信息技术股份有限公司 | Heat radiation structure and active noise reduction method for auto-correlation phase synchronous control of heat radiation structure |
| CN116292390B (en) * | 2023-05-15 | 2023-10-17 | 合肥联宝信息技术有限公司 | Electronic equipment and fan thereof |
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| JP2005076585A (en) * | 2003-09-02 | 2005-03-24 | Ebara Densan Ltd | Blowing device |
| JP2005234203A (en) * | 2004-02-19 | 2005-09-02 | Citizen Watch Co Ltd | Silencing system and electronic equipment |
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| CN203770238U (en) * | 2014-03-06 | 2014-08-13 | 奇鋐科技股份有限公司 | Active noise reduction system for fan body |
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|---|---|---|---|---|
| JPH0954591A (en) * | 1995-08-14 | 1997-02-25 | Nec Corp | Low-noise fan |
| JP2005076585A (en) * | 2003-09-02 | 2005-03-24 | Ebara Densan Ltd | Blowing device |
| JP2005234203A (en) * | 2004-02-19 | 2005-09-02 | Citizen Watch Co Ltd | Silencing system and electronic equipment |
| CN102954045A (en) * | 2012-10-31 | 2013-03-06 | 浪潮集团有限公司 | Method for reducing noise of server fan by adopting active method |
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| CN104895848A (en) | 2015-09-09 |
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