CN104895848A - Fan self-active type noise reduction system - Google Patents
Fan self-active type noise reduction system Download PDFInfo
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- CN104895848A CN104895848A CN201410080426.2A CN201410080426A CN104895848A CN 104895848 A CN104895848 A CN 104895848A CN 201410080426 A CN201410080426 A CN 201410080426A CN 104895848 A CN104895848 A CN 104895848A
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Abstract
The invention discloses a fan self-active type noise reduction system. The fan self-active type noise reduction system comprises a fan, a pushing set, at least one noise receiving unit and a digital signal processing unit, wherein noises generated by the fan are received by the noise receiving unit and then are transmitted to the digital signal processing unit; and the digital signal processing unit performs operation processing according to a received noise input signal and then outputs a control signal to control a pushing coil set to actuate, so that fan wheels of the fan are pushed to move up and down and reverse sound waves are generated to balance out noises, thereby achieving fan self-active type noise reduction effect.
Description
[technical field]
The present invention has about a kind of fan system, and espespecially a kind of have through autologous effect and the autologous active mode denoise system of cost-effective fan initiatively reaching noise reduction of fan.
[background technique]
Because computer has been the electronic equipment that today, people commonly used, and most of computer all will process many data operation every day, but process data more time, central processing unit (Central Processing Unit in computer, be called for short CPU) high heat must be produced, make to cause central processing unit to operate unstable, easily make computer produce misoperation, even produce computer when machine phenomenon, and then the electronic component of computer internal work time serious, can be burnt.So general industry is all utilize fan to carry out to electronic component (as central processing unit, drawing wafer or north and south bridge wafer) forced heat radiation, computer can be stablized in running, though but the problem of heat radiation in fan settlement computer, but extending another problem, is exactly that fan can produce the problem that noise brings puzzlement in time operating.
And the noise problem that fan produces, dealer is made to be subject to suitable attention, because noise can make people produce uneasiness in various degree and Anxiety, increase tired degree, reduce task performance, psychology and physiological injury can be caused what is more, so, effectively abating the noise not only academicly having its meaning, industrially having use value, and the improvement in daily life is also very helpful.The general active noise control of fan is at present through the noise that one or more radio reception MIC microphone acquisition fan produces, and produce a noise input signal and send a digital signals microprocessor (Digital Signal Processor to, be called for short DSP), after making this digital signals microprocessor do calculation process according to the noise input signal received, export one to control on one or more loudspeakers that signal sends connection to and to drive, make aforementioned speakers send reverse sound wave (or claiming reverse source of sound) with offset noise.
Although the active noise control of fan can reach the effect of offset noise, but it extends another problem, be exactly be not the noise of single acquisition to fan in aforementioned radio reception MIC microphone place, also have the reverse source of sound that loudspeaker sends to reflect in environment space simultaneously, and it is superimposed with the noise in environment space, the noise input signal that this digital signals microprocessor is received contains noise and the noise superposed in environment space of fan and reflects source of sound, cause doing the complicated high and reverse source of sound produced of computing and effectively cannot offset the noise and the noise superposed in environment space and reflection source of sound that fan produces, so that cause, noise reduction is not good and cost of equipment is expensive, therefore the active noise control of known fan can only be offset radio reception MIC microphone and placed that noise of position, dealer is made still how to overcome this technical problem in positive effort at present.
The above is known has following shortcoming:
1. noise reduction is not good.
2. apparatus expensive cost is high.
How will solve the above-mentioned problem commonly used and disappearance, the inventor being this case and the relevant manufactures being engaged in the industry desire most ardently place, the direction person studying improvement.
[summary of the invention]
Therefore, for effectively solving the above problems, the main purpose of the present invention is providing a kind of autologous active mode denoise system of fan with better noise reduction.
Another object of the present invention has the autologous active mode denoise system of the fan reduced costs providing a kind of.
In order to reach above-mentioned purpose, the invention provides the autologous active mode denoise system of a kind of fan, comprise: fan, comprise framework, axle bed and impeller, this impeller has magnetic axle center and plural blade, the one end in this magnetic axle center is fixedly arranged on the centre of this impeller, this framework has one and is installed with space, and this axle bed is arranged on the centre in this containing space, and has axis hole, this axis hole content is provided with at least one bearing, and this bearing is pivoted mutually with the other end in relative magnetic axle center; Promotion group, it has a propelling coil group, and this propelling coil group is located in this axis hole, and this bearing adjacent respond to excitatory with relative magnetic axle center, to promote this magnetic axle center axially bottom offset, this impeller is made to produce reverse sound wave, to offset the noise that this fan produces; At least one radio unit, is located in this framework, its noise produced according to this fan of acquisition, and produces noise input signal; And digital signals processing unit, its one end is electrically connected this radio unit, its the other end is then electrically connected this propelling coil group, and this digital signals processing unit exports one after doing calculation process according to the noise input signal received and controls signal, to control this propelling coil group start.
Through the design of the autologous active mode denoise system of this fan of the present invention, obtain the effect person effectively reaching better noise reduction and reduce costs.
This digital signals processing unit comprises: digital signals microprocessor, preamplifier amplifiers, post-amplifier, class specific speed bit pad and numerical digit turn analogy converter, preamplifier amplifiers is electrically connected this radio unit and class specific speed bit pad respectively, this digital signals processor is electrically connected such specific speed bit pad respectively and numerical digit turns analogy converter, and post-amplifier is electrically connected this numerical digit respectively and turns analogy converter and propelling coil group.
This radio unit is radio reception MIC microphone, on the top that this radio unit is arranged at this framework and relatively this impeller.
This magnetic axle center has the first magnetic pole and the second magnetic pole, and this first magnetic pole is positioned on the magnetic axle center of this propelling coil group one end adjacent, and this second magnetic pole is positioned on the magnetic axle center of this propelling coil group the other end adjacent.
This axle bed has supporting portion, this supporting portion protrudes out formation from this axle bed inwall towards the center of this axis hole, and it is provided with the first platform and the second platform, this the first platform is formed in the top of this supporting portion, this the second platform is then formed in the bottom of this supporting portion, and these bearings have clutch shaft bearing and the second bearing, this clutch shaft bearing is placed on the first relative platform, and this second bearing is placed on the second relative platform.
The other end outer concave in this magnetic axle center is provided with a groove, and this groove is positioned at below this second bearing relative to be located, and it is fixed with for a fixed block sandwiched, and defines a displacement space between this groove and the second relative bearing.
This fan more comprises a controller, this controller is electrically connected aforementioned digital signals processing unit, it is in order to transmit a rotational frequency signal to this digital signals processing unit, this digital signals processing unit is made to be reference point according to the phase place of this rotational frequency signal of reception, to adjust the phase place of noise input signal and to do calculation process, and export another control signal, to control this propelling coil group start.
The present invention separately provides a kind of fan autologous active mode denoise system, comprise: fan, comprise framework, axle bed and an impeller, this impeller has axle center and plural blade, and the one end in this axle center is fixedly arranged on the centre of this impeller, and this framework has one and is installed with space, this axle bed is arranged on the centre in this containing space, and there is an axis hole, this axis hole content is provided with at least one bearing, and this bearing is pivoted mutually with the other end in relative axle center; Promotion group, it has housing, propelling coil group and magnetic part, this housing butts up against the bottom of this axle bed, and it is provided with the containing space being relatively communicated with this axis hole, this containing space content is provided with this propelling coil group and magnetic part, and this magnetic part one end connects the other end in this axle center relatively, and with to should propelling coil group respond to excitatory, to promote this axle center axially bottom offset, this impeller is made to produce reverse sound wave, to offset the noise that this fan produces; At least one radio unit, is located in this framework, its noise produced according to this fan of acquisition, and produces noise input signal; And digital signals processing unit, its one end is electrically connected this radio unit, its the other end is then electrically connected this propelling coil group, and this digital signals processing unit does output control signal after calculation process, to control this propelling coil group start according to the noise input signal received.
Through the design of the autologous active mode denoise system of this fan of the present invention, obtain the effect person effectively reaching better noise reduction and reduce costs.
This digital signals processing unit comprises: digital signals microprocessor, preamplifier amplifiers, post-amplifier, class specific speed bit pad and numerical digit turn analogy converter, preamplifier amplifiers is electrically connected this radio unit and class specific speed bit pad respectively, this digital signals processor is electrically connected such specific speed bit pad respectively and numerical digit turns analogy converter, and post-amplifier is electrically connected this numerical digit respectively and turns analogy converter and propelling coil group.
This radio unit is radio reception MIC microphone, on the top that this radio unit is arranged at this framework and relatively this impeller.
This magnetic part is magnet, and this magnetic part has the first magnetic pole and one second magnetic pole, and this first magnetic pole is positioned on one end of this magnetic part, and the other end in this axle center adjacent, this second magnetic pole is positioned on the other end of this magnetic part, and the bottom side in this housing adjacent.
This axle bed has supporting portion, this supporting portion protrudes out formation from this axle bed inwall towards the center of this axis hole, and it is provided with the first platform and the second platform, this the first platform is formed in the top of this supporting portion, this the second platform is then formed in the bottom of this supporting portion, and these bearings have clutch shaft bearing and the second bearing, this clutch shaft bearing is placed on the first relative platform, and this second bearing is placed on the second relative platform.
The other end outer concave in this magnetic axle center is provided with groove, and this groove is positioned at below this second bearing relative to be located, and it is fixed with for a fixed block sandwiched, and defines a displacement space between this groove and the second relative bearing.
This fan more comprises controller, this controller is electrically connected aforementioned digital signals processing unit, it is in order to transmit a rotational frequency signal to this digital signals processing unit, this digital signals processing unit is made to be reference point according to the phase place of this rotational frequency signal of reception, to adjust the phase place of noise input signal and to do calculation process, and export another control signal, to control this propelling coil group start.
[accompanying drawing explanation]
The combination schematic perspective view of Fig. 1 the present invention first preferred embodiment.
The exploded perspective schematic diagram of Fig. 2 the present invention first preferred embodiment.
The block schematic diagram of Fig. 3 the present invention first preferred embodiment.
The combination generalized section of Fig. 4 A the present invention first preferred embodiment.
Another combination generalized section of Fig. 4 B the present invention first preferred embodiment.
Another combination generalized section of Fig. 4 C the present invention first preferred embodiment.
The block schematic diagram of Fig. 5 the present invention second preferred embodiment.
The combination schematic perspective view of Fig. 6 the present invention the 3rd preferred embodiment.
The exploded perspective schematic diagram of Fig. 7 the present invention the 3rd preferred embodiment.
The block schematic diagram of Fig. 8 the present invention the 3rd preferred embodiment.
The combination generalized section of Fig. 9 A the present invention the 3rd preferred embodiment.
Another combination generalized section of Fig. 9 B the present invention the 3rd preferred embodiment.
Another combination generalized section of Fig. 9 C the present invention the 3rd preferred embodiment.
The block schematic diagram of Figure 10 the present invention the 4th preferred embodiment.
The component name that in figure, each reference character is corresponding is:
The autologous active mode denoise system of fan ... 1,2
Fan ... 10,20
Framework ... 101,201
Be installed with space ... 1011,2011
Axle bed ... 102,202
Supporting portion ... 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 plate group ... 1071,2071
Coil groups ... 1072,2072
Magnet ... 108,208
Controller ... 109,209
Promotion group ... 13,23
Propelling coil group ... 131,231
Housing ... 232
Containing 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
Preamplifier amplifiers ... 162,272
Post-amplifier ... 163,273
Class specific speed bit pad ... 164,274
Numerical digit turns analogy converter ... 165,275
Fixed block 3
[embodiment]
Characteristic on above-mentioned purpose of the present invention and structure and fuction thereof, will be explained according to the preferred embodiment of institute's accompanying drawings.
The invention provides the autologous active mode denoise system of a kind of fan, refer to Fig. 1,2,3 and show, the solid of the first preferred embodiment of display the present invention and block schematic diagram, and be aided with and consult Fig. 4 A and show, the autologous active mode denoise system 1 of this fan comprises fan 10, promotion group 13, at least one radio unit 15 and digital signals processing unit 16, this fan 10 comprises framework 101, axle bed 102, impeller 103, stator 107 and control wafer (not shown), control wafer (as microprocessor, MCU) on the circuit board 106 that the side being arranged on the relative impeller 103 of this axle bed 102 has, this control wafer operates and rotating speed in order to control fan 10, this stator 107 is sheathed on the outside of this axle bed 102, and the magnet 108 relatively had in this impeller 103, and this stator 107 has a silicon steel plate group 1071 and is wound in the coil groups 108 in silicon steel plate group 1071.
Aforementioned impeller 103 has a magnetic axle center 1031 and plural blade 1032, the one end in this magnetic axle center 1031 is fixedly arranged on the centre of this impeller 103 relatively, its the other end outer concave is provided with groove 10311, and this groove 10311 is fixed with for fixed block 3 (as C type clasp) sandwiched.Described framework 101 has and is installed with space 1011, this axle bed 102 is arranged on this and is installed with centre in space 1011, and it has and is communicated with this and is installed with axis hole 1023 and the supporting portion 1021 in space 1011, this supporting portion 1021 protrudes out formation from this axle bed 102 inwall towards the center of this axis hole 1023, and it is provided with the first platform 10211 and the second platform 10212, this the first platform 10211 is formed in the top of this supporting portion 1021, and 10212, this second platform is formed in the bottom of this supporting portion 1021.
And aforementioned axis hole 1023 content is provided with at least one bearing 104, this bearing 104 is pivoted mutually with the other end in relative magnetic axle center 1031, and explain in the bearing 104 of this preferred embodiment with 2 bearings, that is these bearings 104 have clutch shaft bearing 1041 and the second bearing 1042, this clutch shaft bearing 1041 is placed on this first relative platform 10211, this second bearing 1042 is placed on relative second platform 10212, and it is positioned at locating above the groove 10311 in magnetic axle center 1031, in other words, described exactly groove 10311 is positioned at the below place of relatively aforementioned second bearing 1042.And define a displacement space 105 between this groove 10311 and the second relative bearing 1042, the activity space of this displacement space 105 for magnetic axle center 1031 axially bottom offset.
Continue and consult Fig. 2, 3, shown in 4A, aforementioned promotion group 13 has a propelling coil group 131, this propelling coil group 131 is located in axis hole 1023, and adjacent aforementioned bearings 104 respond to excitatory with relative magnetic axle center 1031, that is this propelling coil group 131 be positioned at this axis hole 1023 this first, two bearings 1041, between 1042, and one first magnetic pole 10313 and one second magnetic pole 10314 that have of this magnetic axle center 1031 relatively, in this comparatively embodiment first, two magnetic poles 10313, 10314 explain with N pole and S pole respectively, but Bing Bu Authority is limited to this, in time specifically implementing, also can be designed to this first, two magnetic poles 10313, 10314 are respectively S pole and N pole.
So make aforementioned propelling coil group 131 be energized start time can produce magnetic field, with first of magnetic axle center 1031, the magnetic force mutual repulsion effect of two magnetic poles (i.e. N pole and S pole), and promote magnetic axle center 1031 in running can in displacement space 105 axially bottom offset (as consult Fig. 4 A, 4B, shown in 4C), while this impeller 103 in order running provides air quantity, also can produce a reverse sound wave, wherein this reverse sound wave is identical with the amplitude size of the noise that fan 10 produces and the sound wave that phase place is contrary, this reverse sound wave is in order to interfere or to offset impeller 103 running noise.The first magnetic pole 10313 (i.e. N pole) wherein in the magnetic axle center 1031 of this preferred embodiment is positioned on the magnetic axle center 1031 of one end of this propelling coil group 131 adjacent, and second magnetic pole 10314 (i.e. S pole) be positioned at the other end of this propelling coil group 131 adjacent magnetic axle center 1031 on explain, but Bing Bu Authority is limited to this; In time specifically implementing, the magnetic in described magnetic axle center 1031 also can be designed to the second magnetic pole 10314 and be positioned on the magnetic axle center 1031 of this propelling coil group 131 one end adjacent, and the first magnetic pole 10313 is positioned on the magnetic axle center 1031 of the other end of this propelling coil group 131 adjacent.
So by fan 10 of the present invention autologous be sound generation source, while aforementioned impeller 103 produces noise, immediately through the reverse sound wave of the autologous generation of this fan 10, effectively to interfere or offset noise, and then also effectively prevent fan 10 noise source of sound from producing reflection in environment space and forming complicated noise source of sound, therefore, make the effect of dispersing significantly reducing noise amplitude effectively ahead of time and suppress noise, and then due to digital signals processing unit 16 receive signal source (i.e. noise source of sound) relatively simple, make it low in calculation process complexity, use and effectively reach low-cost effect.
Aforementioned radio unit 15 is a radio reception MIC microphone, it to be located in this framework 101 and this impeller 103 relatively, radio reception MIC microphone in this preferred embodiment is installed on the top of this framework 101, and this impeller 103 relatively, its noise produced in running according to the impeller 103 of acquisition (or reading) this fan 10, and produce noise input signal and send aforementioned digital signals processing unit 16 to, and this digital signals processing unit 16 in this preferred embodiment to be arranged on the bottom of this framework 101 adjacent, and this fan 10 more comprises one in order to control the controller 109 of rotation speed of the fan and running, this controller 109 is located on circuit board 106, the side that this circuit board 106 is arranged on the relative impeller 103 of this axle bed 102 explains, that is this digital signals processing unit 16 operation independent process noise signal control promotion group 13 start, the controller of described fan 10 then independently controls fan 10 and operates and rotating speed.
And in time specifically implementing, aforementioned digital signals processing unit 16 also can with the controller of fan 10 (as microprocessor, MCU) design integration is on same circuit board 106, make this digital signals processing unit 16 operation independent process noise signal and control promotion group 13 start, the control wafer of described fan 10 then independently controls fan 10 and operates and rotating speed, or when another is specifically implemented, this digital signals processing unit 16 also can directly design on the circuit board 106 of the side of this axle bed 102, to replace the controller (i.e. the controller of fan-free) of original fan 10, through digital signal microprocessor 161 (the Digital Signal Processor of single digital signals processing unit 16, DSP) control fan 10 to operate and rotating speed, and process noise signal simultaneously and control the start of promotion group 13, close first Chen Ming.
Refer to shown in Fig. 3,4A, one end of aforementioned digital signals processing unit 16 is electrically connected this radio unit 15, its the other end is then electrically connected this propelling coil group 131, it exports one after doing calculation process according to the noise input signal received and controls signal, to control this propelling coil group 131 start, control signal and the start that is energized produce magnetic field as this propelling coil group 131 receives.And this digital signals processing unit 16 comprises aforementioned digital signals microprocessor 161, preamplifier amplifiers 162 (Pre-Amplifier, or claim pre-stage amplifiers), post-amplifier 163 (Power Amplifier, or claim power amplifier), class specific speed bit pad 164 (Analogue to Digital Converter, be called for short ADC) and a numerical digit turn analogy converter 165 (Digital to Analogue Converter is called for short DAC).
Described preamplifier amplifiers 162 has the characteristic of interference resistant, its one end is electrically connected this radio unit 15, its the other end is then electrically connected such specific speed bit pad 164, and this preamplifier amplifiers 162 the noise input signal that this radio unit 15 transmits is done signal amplify process after, export the noise input signal after amplifying, and aforementioned class specific speed bit pad 164 is converted to digital signals (the numerical digit noise input signal after namely amplifying) according to the noise input signal after receiving described amplification.
And aforementioned digital signals microprocessor 161 is electrically connected such specific speed bit pad 164 respectively and numerical digit turns analogy converter 165, it exports a reverse digital signals according to receiving after aforementioned digital signals does calculation process, and send this numerical digit to and turn analogy converter 165, make this numerical digit turn analogy converter 165 and the reverse digital signals received is converted to reverse analog signal.And this post-amplifier 163 is electrically connected the propelling coil group 131 that this numerical digit turns analogy converter 165 and promotion group 13 respectively, it amplifies process in order to the signal power that will receive, that is aforementioned post-amplifier 163 is by after the reverse analog signal power amplification process of reception, output control signal (or being called the analogy audio signal after amplification), to control this propelling coil group 131 start.
So when fan 10 is in time operating and produce noise, this radio unit 15 captures the noise that relative impeller 103 sends at any time in framework 101, and produce noise input signal and send preamplifier amplifiers 162 to, after the noise input signal of reception is done signal amplification process by preamplifier amplifiers 162, export the noise input signal after this amplification and send such specific speed bit pad 164 again to, through class specific speed bit pad 164 (ADC), the noise input signal after amplification is converted to digital signals, this digital signals microprocessor 161 (DSP) is made to export reverse digital signals according to receiving after digital signals does calculation process, and send described numerical digit to and turn analogy converter 165 (DAC) reverse digital signals is converted to reverse analog signal, after the reverse analog signal power received then is amplified process by this post-amplifier 163, and output control signal sends this propelling coil group 131 to, and then control this propelling coil group 131 be energized start produce magnetic field, to respond to excitatory with corresponding magnetic axle center 1031, and promote the impeller 103 in running magnetic axle center 1031 can in aforementioned displacements space 105 axially bottom offset (as consult 4A, 4B, 4C illustrates), impeller 103 is made to produce the reverse sound wave of (or sending) identical with the amplitude size of the noise that fan 10 produces, but oppositely the phase place of sound wave is contrary with the phase place of aforementioned noise, with the noise effectively interfering or eliminate fan 10 to produce in time operating.
Therefore, through this promotion group 13 start of control that the digital signals processing unit 16 of the present invention is in good time, to respond to excitatory with magnetic axle center 1031, promote magnetic axle center 1031 upper and lower displacement, make impeller 103 autologously send reverse sound wave to offset system that (or interference) fan 10 produces noise, the effect that effectively reach preferably noise reduction and reduce costs, and then also effectively avoid fan 10 noise source of sound produce reflection in environment space and form the effect of complicated noise source of sound.
Refer to the 5th diagram, the block schematic diagram of the second preferred embodiment of display the present invention, and be aided with consult the 3rd, 4A diagram, the structure of this this preferred embodiment and linking close and effect roughly identical with aforementioned first preferred embodiment, therefore again do not repeat at this, difference both it be in: the controller 109 of aforementioned fan 10 is electrically connected the digital signals microprocessor 161 of this digital signals processing unit 16, it is in order to transmit a rotational frequency signal to the digital signals microprocessor 161 of this digital signals processing unit 16, and aforementioned digital signals processing unit 16 is reference point according to the phase place receiving rotational frequency signal, to adjust the phase place of noise input signal and to do calculation process, and export another control signal, to control this propelling coil group 131 start.
Wherein this rotational frequency signal (or being called FG (Frequency Generator) signal) is for representing the signal of the rotating speed of fan, and in the frequency of the noise of in fact this fan 10 generation identical with the frequency of rotational frequency signal (or synchronous), and owing to having distance between radio unit 15 and blade 1032, delay is had when making this radio unit 15 receive the noise of fan 10 generation, therefore it is as a reference point to send digital signals microprocessor (DSP) 161 of this digital signals processing unit 16 to through this rotational frequency signal, this digital signals microprocessor 161 is made suitably to postpone the phase place of the digital signals received according to reference point and do calculation process, and output is same as another the reverse digital signals with the phase difference 180 degree of noise sound wave, such as described digital signals microprocessor 161 is reference point according to the phase place receiving this rotational frequency signal, the phase difference 175 degree adjusting digital signals (i.e. noise input signal) and the noise in fact received is deferred to phase difference and equals (or close to) 180 degree and do calculation process, and export another the reverse digital signals being same as (or close to) and the phase difference 180 degree of noise sound wave.
So when fan 10 is in time operating and produce noise, this radio unit 15 captures the noise that relative impeller 103 sends at any time in framework 101, and produce aforementioned noise input signal and send preamplifier amplifiers 162 to, after the noise input signal of reception is done signal amplification process by preamplifier amplifiers 162, export the noise input signal after this amplification and send such specific speed bit pad 164 again to, through class specific speed bit pad 164 (ADC), the noise input signal after amplification is converted to digital signals, now described digital signals microprocessor (DSP) 161 can receive rotational frequency signal and digital signals simultaneously, and be reference point according to the phase place of the rotational frequency signal received, to adjust the phase delay that receives digital signals (namely amplify after numerical digit noise input signal) and after doing calculation process, export another reverse digital signals, and send described numerical digit to and turn analogy converter 165 (DAC) another reverse digital signals is converted to another reverse analog signal, after another the reverse analog signal power received then is amplified process by this post-amplifier 163, and export another control signal send this propelling coil group 131 to, and then control this propelling coil group 131 be energized start produce magnetic field, to respond to excitatory with corresponding magnetic axle center 1031, and promote the impeller 103 in running magnetic axle center 1031 can in aforementioned displacements space 105 axially bottom offset (as consult Fig. 4 A, 4B, shown in 4C), oppositely sound wave is identical with the amplitude size of the noise that fan 10 produces to make impeller 103 produce (or sending), but oppositely the phase place of sound wave is contrary with the phase place of aforementioned noise, with the noise effectively interfering or eliminate fan 10 to produce in time operating.
In addition, if when the noise that fan 10 produces in operating is eliminated, this radio unit 15 can almost can not receive noise input signal, the digital signals that this digital signals microprocessor 161 is received also can be very faint, and then the rotational frequency signal received just can be Primary Reference signal and do running process, and export another reverse signal identical with the frequency of noise, use the effect reaching and maintain payment noise.
Therefore the rotational frequency signal transmitted through the controller 109 of the present invention is reference point use to digital signals processing unit 16, uses the design of the phase place of suitable delay digit signal, make effectively to reach the noise that smart Quasi interferes or eliminate fan 10 to produce in time operating.
Refer to shown in Fig. 6,7,8, the solid of the 3rd preferred embodiment of display the present invention and block schematic diagram, and be aided with and consult shown in Fig. 9 A, the autologous active mode denoise system 2 of this fan comprises fan 20, promotion group 23, at least one radio unit 26 and digital signals processing unit 27, this fan 20 comprises framework 201, axle bed 202, impeller 203, stator 207 and control wafer, control wafer (as microprocessor, MCU) on the circuit board 206 that the side being arranged on the relative impeller 203 of this axle bed 202 has, it operates and rotating speed in order to control fan 20, this stator 207 is sheathed on the outside of this axle bed 202, and the magnet 208 relatively had in this impeller 203, and this stator 207 has a silicon steel plate group 2071 and is wound in the coil groups 208 in silicon steel plate group 2071.
Aforementioned impeller 203 has an axle center 2031 and plural blade 2032, the one end in this axle center 2031 is fixedly arranged on the centre of this impeller 203 relatively, its the other end outer concave is provided with groove 20311, and this groove 20311 is fixed with for fixed block 3 (as C type clasp) sandwiched.Described framework 201 has one and is installed with space 2011, this axle bed 202 is arranged on this and is installed with centre in space 2011, and it has a connection, and this is installed with axis hole 2023 and a supporting portion 2021 in space 2011, this supporting portion 2021 protrudes out formation from this axle bed 202 inwall towards the center of this axis hole 2023, and it is provided with the first platform 20211 and the second platform 20212, this the first platform 20211 is formed in the top of this supporting portion 2021, and 20212, this second platform is formed in the bottom of this supporting portion 2021.
And aforementioned axis hole 2023 is from the top of this axle bed 202 towards running through bottom it, and its content is provided with at least one bearing 204, this bearing 204 is pivoted mutually with the other end in relative axle center 2031, and explain in the bearing 204 of this preferred embodiment with 2 bearings, that is these bearings 204 have clutch shaft bearing 2041 and the second bearing 2042, this clutch shaft bearing 2041 is placed on this first relative platform 20211, this second bearing 2042 is placed on relative second platform 20212, and place above its groove 20311 being positioned at corresponding axle center 2031, in other words, described exactly groove 20311 is positioned at the below place of relatively aforementioned second bearing 2042.And define displacement space 205 between this groove 20311 with relative second bearing 2042, the activity space of this displacement space 205 for axle center 2031 axially bottom offset.
Continue and consult Fig. 7, 8, shown in 9A, aforementioned promotion group 23 has housing 232, propelling coil group 231 and magnetic part 234, this housing 232 butts up against on the bottom of this axle bed 202, and it is provided with containing space 2321, this containing space 2321 is communicated with corresponding axis hole 2023, and its content is provided with this propelling coil group 231 and magnetic part 234, described magnetic part 234 is magnet, one end of this magnetic part 234 connects the other end running through the axle center 2031 of this its upper bottom portion of axle bed 202, and aforementioned magnetic part 234 is positioned at the below place of this second bearing 2042, and with to should propelling coil group 231 respond to excitatory, that is the propelling coil group 231 in this containing space 2321 is between this magnetic part 234 and housing 232 madial wall, and the first magnetic pole 2341 and the second magnetic pole 2342 that relative magnetism part 234 has, so make aforementioned propelling coil group 231 be energized start time can produce magnetic field, with first of magnetic part 234, two magnetic poles 2341, the magnetic force mutual repulsion effect of 2342 (i.e. N pole and S poles), and promote axle center 2031 in running can in displacement space 205 axially bottom offset (as consult Fig. 9 A, 9B, shown in 9C), while this impeller 203 in order running provides air quantity, also can produce a reverse sound wave, wherein this reverse sound wave is identical with the amplitude size of the noise that fan 20 produces and the sound wave that phase place is contrary, this reverse sound wave is in order to interfere or to offset impeller 203 running noise.On the one end being wherein positioned at magnetic part 234 in the first magnetic pole 2341 (i.e. N pole) of the magnetic part 234 of this preferred embodiment and relative second bearing 2042, and second magnetic pole 2342 (i.e. S pole) be positioned on the other end of this magnetic part 234, and the bottom side in this housing 232 adjacent explains, but Bing Bu Authority is limited to this; In time specifically implementing, the magnetic of described magnetic part 234 also can be designed on one end that the second magnetic pole 2342 is positioned at magnetic part 234 and relative second bearing 2042, and the first magnetic pole 2341 is positioned on the other end of this magnetic part 234, and the bottom side in this housing 232 adjacent.
So by fan 20 of the present invention autologous be sound generation source, while aforementioned impeller 203 produces noise, immediately through the reverse sound wave of the autologous generation of this fan 20, effectively to interfere or offset noise, and then also effectively prevent fan 20 noise source of sound from producing reflection in environment space and forming complicated noise source of sound, therefore, make the effect of dispersing significantly reducing noise amplitude effectively ahead of time and suppress noise, and then due to digital signals processing unit 27 receive signal source (i.e. noise source of sound) relatively simple, make it low in calculation process complexity, use and effectively reach low-cost effect.
Aforementioned radio unit 26 is radio reception MIC microphone, close and effect and aforementioned first preferred embodiment identical in the structure and linking of the radio unit 26 of this better enforcement, be all the noise of impeller 203 generation in running in order to acquisition (or reading) fan 20, therefore be not again described in detail at this.And in the digital signals microprocessor 271 (DSP) that the digital signals processing unit 27 of this this preferred embodiment comprises, preamplifier amplifiers 272 (Pre-Amplifier), post-amplifier 273 (Power Amplifier), class specific speed bit pad 274 (ADC) and numerical digit turn each element structure of analogy converter 275 (DAC) and link digital signals processing unit 16 and interior each element (i.e. digital signals microprocessor 161 thereof of pass and effect and aforementioned first preferred embodiment, preamplifier amplifiers 162, post-amplifier 163, class specific speed bit pad 164 and numerical digit turn analogy converter 165) identical, therefore again do not repeat at this, close first Chen Ming.
In addition, in time specifically implementing, the digital signals processing unit 27 of this preferred embodiment is identical with aforementioned first preferred embodiment with the collocation design mode of the controller 209 (as microprocessor, MCU) of fan 20, therefore does not again repeat at this.
So when fan 20 is in time operating and produce noise, this radio unit 26 captures the noise that relative impeller 203 sends at any time in framework 201, and produce noise input signal and send preamplifier amplifiers 272 to, after the noise input signal of reception is done signal amplification process by preamplifier amplifiers 272, export the noise input signal after this amplification and send such specific speed bit pad 274 again to, through class specific speed bit pad 274 (ADC), the noise input signal after amplification is converted to digital signals, this digital signals microprocessor 271 (DSP) is made to export reverse digital signals according to receiving after digital signals does calculation process, and send described numerical digit to and turn analogy converter 275 (DAC) reverse digital signals is converted to reverse analog signal, after the reverse analog signal power received then is amplified process by this post-amplifier 273, and output control signal sends this propelling coil group 231 to, and then control this propelling coil group 231 be energized start produce magnetic field, to respond to excitatory with corresponding magnetic part 234, and promote the impeller 203 in running axle center 2031 can in aforementioned displacements space 205 axially bottom offset (as consult 9A, 9B, 9C illustrates), impeller 203 is made to produce the reverse sound wave of (or sending) identical with the amplitude size of the noise that fan 20 produces, but oppositely the phase place of sound wave is contrary with the phase place of aforementioned noise, with the noise effectively interfering or eliminate fan 20 to produce in time operating.
Therefore, through this propelling coil group 231 start of control that the digital signals processing unit 27 of the present invention is in good time, to respond to excitatory with magnetic part 234, promote axle center 2031 upper and lower displacement, make impeller 203 autologously send reverse sound wave to offset system that (or interference) fan 20 produces noise, the effect that effectively reach preferably noise reduction and reduce costs, and then also effectively avoid fan 20 noise source of sound produce reflection in environment space and form the effect of complicated noise source of sound.
Refer to shown in Figure 10, the block schematic diagram of the 4th preferred embodiment of display the present invention, and be aided with and consult shown in Fig. 8,9A, the structure of this this preferred embodiment and linking close and effect roughly identical with aforementioned 3rd preferred embodiment, therefore again do not repeat at this, difference both it be in: the controller 209 of aforementioned fan 20 is electrically connected the digital signals microprocessor 271 of this digital signals processing unit 27, it is in order to transmit rotational frequency signal to the digital signals microprocessor 271 of this digital signals processing unit 27, and aforementioned digital signals processing unit 27 is reference point according to the phase place receiving rotational frequency signal, to adjust the phase place of noise input signal and to do calculation process, and export another control signal, to control this propelling coil group 231 start.
Wherein this rotational frequency signal (or being called FG (Frequency Generator) signal) is for representing the signal of the rotating speed of fan, and in the frequency of the noise of in fact this fan 20 generation identical with the frequency of rotational frequency signal (or synchronous), and owing to having distance between radio unit 26 and blade 2032, delay is had when making this radio unit 26 receive the noise of fan 20 generation, therefore it is as a reference point to send digital signals microprocessor (DSP) 271 of this digital signals processing unit 27 to through this rotational frequency signal, this digital signals microprocessor 271 is made suitably to postpone the phase place of the digital signals received according to reference point and do calculation process, and output is same as another the reverse digital signals with the phase difference 180 degree of noise sound wave, such as described digital signals microprocessor 271 is reference point according to the phase place receiving this rotational frequency signal, the phase difference 175 degree adjusting digital signals (i.e. noise input signal) and the noise in fact received is deferred to phase difference and equals (or close to) 180 degree and do calculation process, and export another the reverse digital signals being same as (or close to) and the phase difference 180 degree of noise sound wave.
So when fan 20 is in time operating and produce noise, this radio unit 26 captures the noise that relative impeller 203 sends at any time in framework 201, and produce aforementioned noise input signal and send preamplifier amplifiers 272 to, after the noise input signal of reception is done signal amplification process by preamplifier amplifiers 272, export the noise input signal after this amplification and send such specific speed bit pad 274 again to, through class specific speed bit pad (ADC) 274, the noise input signal after amplification is converted to digital signals, now described digital signals microprocessor (DSP) 271 can receive rotational frequency signal and digital signals simultaneously, and be reference point according to the phase place of the rotational frequency signal received, to adjust the phase delay that receives digital signals (namely amplify after numerical digit noise input signal) and after doing calculation process, export another reverse digital signals, and send described numerical digit to and turn analogy converter (DAC) 275 another reverse digital signals is converted to another reverse analog signal, after another the reverse analog signal power received then is amplified process by this post-amplifier 273, and export another control signal send this propelling coil group 231 to, and then control this propelling coil group 231 be energized start produce magnetic field, to respond to excitatory with corresponding magnetic part 234, and promote the impeller 203 in running axle center 2031 can in aforementioned displacements space 205 axially bottom offset (as consult Fig. 9 A, 9B, shown in 9C), oppositely sound wave is identical with the amplitude size of the noise that fan 20 produces to make impeller 203 produce (or sending), but oppositely the phase place of sound wave is contrary with the phase place of aforementioned noise, with the noise effectively interfering or eliminate fan 20 to produce in time operating.
In addition, if when the noise that fan 20 produces in operating is eliminated, this radio unit 26 can almost can not receive noise input signal, the digital signals that this digital signals microprocessor 271 is received also can be very faint, and then the rotational frequency signal received just can be Primary Reference signal and do running process, and export another reverse signal identical with the frequency of noise, use the effect reaching and maintain payment noise.
Therefore the rotational frequency signal transmitted through the controller 209 of the present invention is reference point use to digital signals processing unit 27, uses the design of the phase place of suitable delay digit signal, make effectively to reach the noise that smart Quasi interferes or eliminate fan 20 to produce in time operating.
The above the present invention has following advantage compared to known:
1. there is preferably noise reduction.
2. effectively can prevent fan noise source of sound from producing reflection in environment space and forming complicated noise source of sound, make digital signals processing unit low in calculation process complexity, use the effect effectively reaching and reduce costs.
3. there is the effect of dispersing significantly reducing noise amplitude ahead of time and suppress noise.
Only the above, the better feasible embodiment of only the present invention, such as utilizes the above-mentioned method of the present invention, shape, structure, device to change for it, all should be contained in the interest field of this case.
Claims (14)
1. the autologous active mode denoise system of fan, it is characterized in that, this fan comprises framework, axle bed and impeller, this impeller has magnetic axle center and plural blade, and the one end in this magnetic axle center is fixedly arranged on the centre of this impeller, and this framework has and is installed with space, this axle bed is arranged on the centre in this containing space, and there is axis hole, this axis hole content is provided with at least one bearing, and this bearing is pivoted mutually with the other end in relative magnetic axle center;
Promotion group, it has propelling coil group, and this propelling coil group is located in this axis hole, and this bearing adjacent respond to excitatory with relative magnetic axle center, to promote this magnetic axle center axially bottom offset, this impeller is made to produce reverse sound wave, to offset the noise that this fan produces;
At least one radio unit, is located in this framework, its noise produced according to this fan of acquisition, and produces noise input signal; Digital signals processing unit, its one end is electrically connected this radio unit, its the other end is then electrically connected this propelling coil group, and this digital signals processing unit does output control signal after calculation process, to control this propelling coil group start according to the noise input signal received.
2. the autologous active mode denoise system of fan according to claim 1, it is characterized in that, described digital signals processing unit comprises: digital signals microprocessor, preamplifier amplifiers, post-amplifier, class specific speed bit pad sum digit turn analogy converter, preamplifier amplifiers is electrically connected this radio unit and class specific speed bit pad respectively, this digital signals processor is electrically connected such specific speed bit pad respectively and numerical digit turns analogy converter, and post-amplifier is electrically connected this numerical digit respectively and turns analogy converter and propelling coil group.
3. the autologous active mode denoise system of fan according to claim 2, is characterized in that, described radio unit is radio reception MIC microphone, on the top that this radio unit is arranged at this framework and relatively this impeller.
4. the autologous active mode denoise system of fan according to claim 3, it is characterized in that, described magnetic axle center has the first magnetic pole and the second magnetic pole, this first magnetic pole is positioned on the magnetic axle center of this propelling coil group one end adjacent, and this second magnetic pole is positioned on the magnetic axle center of this propelling coil group the other end adjacent.
5. the autologous active mode denoise system of fan according to claim 4, it is characterized in that, described axle bed has supporting portion, this supporting portion protrudes out formation from this axle bed inwall towards the center of this axis hole, and it is provided with the first platform and the second platform, this the first platform is formed in the top of this supporting portion, this the second platform is then formed in the bottom of this supporting portion, and these bearings have clutch shaft bearing and one second bearing, this clutch shaft bearing is placed on the first relative platform, and this second bearing is placed on the second relative platform.
6. the autologous active mode denoise system of fan according to claim 5, it is characterized in that, the other end outer concave in described magnetic axle center is provided with a groove, this groove is positioned at below this second bearing relative to be located, it is fixed with for a fixed block sandwiched, and defines a displacement space between this groove and the second relative bearing.
7. the autologous active mode denoise system of the fan according to claim 3 or 6, it is characterized in that, described fan more comprises controller, this controller is electrically connected aforementioned digital signals processing unit, be used for transmitting rotational frequency signal to this digital signals processing unit, make this digital signals processing unit be reference point according to the phase place of this rotational frequency signal of reception, to adjust the phase place of noise input signal and to do calculation process, and export another control signal, to control this propelling coil group start.
8. the autologous active mode denoise system of fan, it is characterized in that this fan, comprise framework, axle bed and impeller, this impeller has an axle center and plural blade, and the one end in this axle center is fixedly arranged on the centre of this impeller, and this framework has one and is installed with space, this axle bed is arranged on the centre in this containing space, and there is an axis hole, this axis hole content is provided with at least one bearing, and this bearing is pivoted mutually with the other end in relative axle center;
Promotion group, it has housing, propelling coil group and magnetic part, this housing butts up against the bottom of this axle bed, and it is provided with the containing space that is communicated with this axis hole relatively, this containing space content is provided with this propelling coil group and magnetic part, and this magnetic part one end connects the other end in this axle center relatively, and with to should propelling coil group respond to excitatory, to promote this axle center axially bottom offset, this impeller is made to produce reverse sound wave, to offset the noise that this fan produces;
At least one radio unit, is located in this framework, according to the noise that acquisition fan produces, and produces noise input signal; And
Digital signals processing unit, its one end is electrically connected this radio unit, its the other end is then electrically connected this propelling coil group, and this digital signals processing unit does output control signal after calculation process, to control this propelling coil group start according to the noise input signal received.
9. the autologous active mode denoise system of fan according to claim 8, it is characterized in that, described digital signals processing unit comprises: digital signals microprocessor, preamplifier amplifiers, post-amplifier, class specific speed bit pad and numerical digit turn analogy converter, preamplifier amplifiers is electrically connected this radio unit and class specific speed bit pad respectively, this digital signals processor is electrically connected such specific speed bit pad respectively and numerical digit turns analogy converter, and post-amplifier is electrically connected this numerical digit respectively and turns analogy converter and propelling coil group.
10. the autologous active mode denoise system of fan according to claim 8, is characterized in that, described radio unit is radio reception MIC microphone, on the top that this radio unit is arranged at this framework and relatively this impeller.
The autologous active mode denoise system of 11. fan according to claim 8, it is characterized in that, described magnetic part is magnet, this magnetic part has the first magnetic pole and the second magnetic pole, this first magnetic pole is positioned on one end of this magnetic part, and the other end in this axle center adjacent, this second magnetic pole is positioned on the other end of this magnetic part, and the bottom side in this housing adjacent.
The autologous active mode denoise system of 12. fan according to claim 8, it is characterized in that, described axle bed has supporting portion, this supporting portion protrudes out formation from this axle bed inwall towards the center of this axis hole, and it is provided with the first platform and the second platform, this the first platform is formed in the top of this supporting portion, this the second platform is then formed in the bottom of this supporting portion, and these bearings have clutch shaft bearing and the second bearing, this clutch shaft bearing is placed on the first relative platform, and this second bearing is placed on the second relative platform.
The autologous active mode denoise system of 13. fan according to claim 8, it is characterized in that, the other end outer concave in described magnetic axle center is provided with a groove, this groove is positioned at below this second bearing relative to be located, it is fixed with for a fixed block sandwiched, and defines a displacement space between this groove and the second relative bearing.
14. autologous active mode denoise systems of fan according to claim 9 or 12 is characterized in that, described fan more comprises controller, this controller is electrically connected aforementioned digital signals processing unit, it is in order to transmit rotational frequency signal to this digital signals processing unit, this digital signals processing unit is made to be reference point according to the phase place of this rotational frequency signal of reception, to adjust the phase place of noise input signal and to do calculation process, and export another control signal, to control this propelling coil group start.
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| CN201410080426.2A CN104895848B (en) | 2014-03-06 | 2014-03-06 | The autologous active noise reduction system of fan |
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| CN201410080426.2A CN104895848B (en) | 2014-03-06 | 2014-03-06 | The autologous active noise reduction system of fan |
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| CN104895848B CN104895848B (en) | 2017-07-14 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114321024A (en) * | 2021-12-31 | 2022-04-12 | 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 |
| CN116292390A (en) * | 2023-05-15 | 2023-06-23 | 合肥联宝信息技术有限公司 | Electronic equipment and fan thereof |
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| 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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| CN104895848B (en) | 2017-07-14 |
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