CN1566960A - Fan condition detecting method and apparatus therefor - Google Patents
Fan condition detecting method and apparatus therefor Download PDFInfo
- Publication number
- CN1566960A CN1566960A CN 03147902 CN03147902A CN1566960A CN 1566960 A CN1566960 A CN 1566960A CN 03147902 CN03147902 CN 03147902 CN 03147902 A CN03147902 A CN 03147902A CN 1566960 A CN1566960 A CN 1566960A
- Authority
- CN
- China
- Prior art keywords
- fan
- signal
- rotation speed
- output
- shaping
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Abstract
This invention discloses a detecting method for fan status and its apparatus. The steps of the said method are the following: a, to extract fan rotation impulse signals from fan power circuit; b to shape the said fan rotation impulse signals; c, to detect wave shape of the signals and to determine the relevant status according to the signals. The said apparatus comprises extracting device, shape device and detecting device. This invention is free of impacts of fan type and rotation type and can be widely used in fan detecting environment due to adopting fan power circuit to extract impulse signals.
Description
Technical field
The present invention relates to the state inspection in the electronic technology, refer to a kind of fan-status detection method and device especially.
Background technology
Present various electronic products, especially some integrated level height, high-power electronic equipment often can produce a large amount of heats in the operational process, if the untimely discharge of a large amount of heats, then can influence the stable of electronic equipment operation more or less, even reduce the performance of electronic equipment.Various for this reason fans just are widely used in the electronic equipment.
But the use of fan also brings to electronic equipment increases, increases problems such as dustproof difficulty, power consumption increase, reliability reduction as: noise, for addressing the above problem timely and effectively, becomes key just the fan work state detected timely and effectively.
At present, fan is divided into two kinds in the fan of fan that detection signal is arranged and no detection signal usually.In order to detect fan state,, need to adopt the fan checkout equipment that has special chip for the fan of no detection signal.Its shortcoming is: owing to the dedicated fan control chip that needs to adopt cost higher in described checkout equipment, therefore increased the cost of fan checkout equipment.
For the fan that detection signal is arranged, generally by being arranged on the circuit extraction of fan inside, as in fan inside the fan sensor being set, the sensing fan-status is also by special detection feedback signal wire output for the fan detection signal.When detecting fan and break down, by concurrent warnings of being out of order of signal lines output stall detection signal, described stall detection signal as shown in Figure 1, promptly the failure alarm signal shown in usually when the complete stall of fan, is exported high level; Otherwise, be low level.
But in practice, also to be subjected to certain limitation when the fan state that detection signal is arranged is detected, may be subjected to the restriction of the general purpose I/O number of CPU in the equipment such as the number of detected fan.In addition, fan-status also is subjected to the restriction of detected rotation speed of the fan control mode when detecting, and for example, controls the fan of rotating speed to adopting width modulation (PWM) mode, can not use the detection feedback signal wire that it is detected.This is that the circuit of fan inside can cut off the power supply the short time, causes supervisory signal unusual owing to when adjusting the rotating speed of pipe by CPU or hardware circuit generation PWM Waveform Control fan, adjusting between the pipe off period.
Summary of the invention
The invention provides a kind of fan-status detection method and device, to solve the fan of prior art to no detection signal output, the problem that the checkout equipment cost is high.
For addressing the above problem, the invention provides following solution:
A kind of fan-status detection method, this method may further comprise the steps:
A) from the fan power supply circuit, extract the rotation speed of the fan pulse signal;
B) the described rotation speed of the fan pulse signal that extracts is carried out shaping;
C) detect the waveform of the signal that described shaping obtains, and determine the corresponding state of fan according to the waveform of described signal.
Described step a) further comprises:
A1) with the coupling of the alternating signal in fan power supply circuit output, described alternating signal is superimposed with the inversion signal of rotation speed of the fan pulse signal and rotation speed of the fan control signal;
A2) rotation speed of the fan control signal coupling is exported to the output terminal of above-mentioned alternating signal, with the inversion signal of offsetting the rotation speed of the fan control signal that superposes in the described alternating signal through coupling output produce noise signal.
A kind of fan-status pick-up unit comprises:
Extraction element, input end links to each other with the fan power supply circuit, is used for extracting rotation speed of the fan pulse signal and output from the fan power supply circuit;
Apparatus for shaping, input end links to each other with extraction element, is used for the rotation speed of the fan pulse signal that extracts is carried out shaping and output;
Pick-up unit, input end links to each other with apparatus for shaping, is used to detect the waveform of the signal of apparatus for shaping output, and determines the corresponding state of fan according to the waveform of described signal.
Described extraction element further comprises:
First coupled circuit is used for the alternating signal coupling output with the fan power supply circuit, and described alternating signal is superimposed with the inversion signal of rotation speed of the fan pulse signal and rotation speed of the fan control signal;
Second coupled circuit, its output terminal links to each other with the first coupled circuit signal output part, be used for rotation speed of the fan control signal coupling output, produce the noise signal of rotation speed of the fan control signal, offset the noise signal that the inversion signal by the rotation speed of the fan control signal of described first coupled circuit output produces.
Compared with prior art, the present invention has following advantage:
1, the present invention is by extracting the rotation speed of the fan pulse signal at the fan power supply end, and utilize the principle that inversely adds that the rotation speed of the fan control signal is eliminated and finally extract the rotation speed of the fan pulse signal, be not subjected to the influence of fan type selecting and rotating speed control mode, can generally be applicable to the environment that fan-status detects;
2, the present invention realizes the device that the rotation speed of the fan pulse signal extracts, and does not adopt logical device, CPU or fan control chip, only uses discrete component, realizes by simple mimic channel, and economy and realization are simple.
3, extract the device of rotation speed of the fan pulse among the present invention, the general purpose I/O number of CPU in the equipment is not required, favorable expandability can conveniently be expanded the detection number of fans.
Description of drawings
Fig. 1 is the failure alarm signal waveform of existing fan detection feedback signal wire output;
Fig. 2 is the process flow diagram of fan-status detection method of the present invention;
Fig. 3 is the process flow diagram that extracts the rotation speed of the fan pulse signal among Fig. 2;
Fig. 4 a-Fig. 4 f is the signal waveform synoptic diagram that extracts the rotation speed of the fan pulse among the present invention;
Fig. 5 is the composition structural drawing of fan-status pick-up unit of the present invention;
Fig. 6 a-Fig. 6 b is schematic diagram and the output waveform synoptic diagram of the present invention by the output rotation speed of the fan pulse signal that is coupled;
Fig. 7 a-Fig. 7 e is schematic diagram and the waveform synoptic diagram of the present invention by the disturbing pulse of the elimination rotation speed of the fan control signal that inversely adds;
Fig. 8 a-Fig. 8 b is schematic diagram and the shaping waveform synoptic diagram that the present invention will export the shaping of rotation speed of the fan pulse signal.
Embodiment
The present invention is further described below in conjunction with accompanying drawing.
The present invention is by extracting the rotation speed of the fan pulse signal and then detecting fan-status.Described rotation speed of the fan pulse signal is one of inherent characteristic of fan, be that the fan rotation certainly leads to rotational speed pulse signal, rotational speed pulse signal is arranged, fan is inevitable to be changeed, in other words, the commentaries on classics that the having or not of rotational speed pulse signal shown fan with do not change, the height of frequency has then shown the speed of rotation speed of the fan.
For rotational speed pulse signal, generally be 2～3 pulses of revolution output.By tacho-pulse is counted, can calculate the rotating speed of fan, also can know fan state, rotational speed pulse signal is normal low or normal height when the fan stall.
In addition, in fan circuit, in order to control the rotating speed of fan, a switching tube is arranged in fan circuit, and described switching tube is opened or is closed by the control of rotation speed of the fan control signal, and described switching tube can be a metal-oxide-semiconductor, it also can be triode, to be example to power supply PWM modulation control rotation speed of the fan, pwm signal is opened or is turn-offed by conditioning signal dutycycle gauge tap pipe, thereby realizes the control to rotation speed of the fan.Described rotation speed of the fan control signal is present in the fan power supply circuit, when extracting the rotation speed of the fan pulse, by the coupling output power supply circuit alternating signal the time, described rotation speed of the fan control signal also is coupled output and forms the noise signal that disturbs the rotation speed of the fan pulse signal to extract, method of the present invention is finally extracted the rotation speed of the fan pulse signal by the noise signal of eliminating fan speed controling signal in the fan power supply circuit just, is described in detail below.
Fig. 2 is the process flow diagram of fan-status detection method of the present invention, mainly may further comprise the steps:
Step 21) from fan power supply circuit extraction rotation speed of the fan pulse signal.As above-mentioned, can detect fan state by described rotation speed of the fan pulse signal, therefore, must at first extract the rotation speed of the fan pulse signal, in addition, in order to extract conveniently, be not subjected to the influence of rotation speed of the fan control mode, described rotation speed of the fan pulse signal extracts from the fan power supply circuit;
Step 22) the described rotation speed of the fan pulse signal that extracts is carried out shaping.Because the rotation speed of the fan pulse signal that extracts also is not the logic level signal of standard, therefore also need further shaping;
Step 23) detects the waveform of the signal that described shaping obtains, and determine the corresponding state of fan according to the waveform of described signal.The waveform of signal is normal low or normal height as described, determine that then fan breaks down, otherwise fan is normal, can determine the rotating speed state of fan according to the number of pulse in the waveform of described signal.
Request in person the process flow diagram that extracts the rotation speed of the fan pulse signal referring to the described the present invention of Fig. 3 down, step 21) extracting the rotation speed of the fan pulse signal further may further comprise the steps: S1) with the coupling of the alternating signal in fan power supply circuit output, described alternating signal is superimposed with the inversion signal of rotation speed of the fan pulse signal and rotation speed of the fan control signal; S2) rotation speed of the fan control signal coupling is exported to the output terminal of above-mentioned alternating signal, with the inversion signal of offsetting the rotation speed of the fan control signal that superposes in the described alternating signal through coupling output produce noise signal.
Above-mentioned steps S1) purpose is for the rotational speed pulse signal in the fan power supply circuit is drawn so that extract, for the rotation speed of the fan pulse is drawn, can realize by a coupled circuit during concrete enforcement, but as can be known from above-mentioned analysis, alternating signal in the fan power supply circuit (shown in Fig. 4 c), not only comprise rotation speed of the fan pulse signal (shown in Fig. 4 f), the inversion signal that also comprises the rotation speed of the fan control signal is (shown in Fig. 4 b, the rotation speed of the fan control signal is seen shown in Fig. 4 a), described alternating signal is after coupling output, please referring to the waveform synoptic diagram of the coupling output signal shown in Fig. 4 d, follow rotation speed of the fan pulse a, two disturbing pulse b have also been produced, the noise signal that the inversion signal that described disturbing pulse b is the rotation speed of the fan control signal produces after being coupled, therefore, want to extract rotation speed of the fan pulse a, must eliminate described disturbing pulse b.In the present embodiment, adopt a kind of simple method, promptly by the inversion signal of this disturbing pulse b is provided, and then can eliminate described disturbing pulse b with described disturbing pulse b stack, therefore, at step S2) in, in the rotation speed of the fan signal input end, further described fan rotating speed signals coupling is exported to the output terminal of above-mentioned alternating signal, signal waveform after the rotation speed of the fan control signal coupling output is seen Fig. 4 e, with after the output terminal of alternating signal links to each other, the positive and negative counteracting of the noise signal of the generation of described rotation speed of the fan control signal and disturbing pulse b (being the noise signal of alternating signal coupling output), signal waveform such as Fig. 4 f of final output, only remaining disturbing pulse a.
The method of the invention described above has been used the principle of positive inversion signal stack to eliminate the rotation speed of the fan control signal to extracting the interference of rotation speed of the fan pulse signal; described rotation speed of the fan control signal may be pwm signal (by dutycycle control speed governing); or high-low level; the oxide-semiconductor control transistors switch; realization is to the control of fan start and stop or rotating speed; because when fan power supply end coupling output rotation speed of the fan pulse signal; described rotation speed of the fan control signal also is coupled into pulse signal output; therefore; eliminating this disturbing pulse signal is key of the present invention; by the principle that inversely adds; it realizes that circuit is fairly simple; by sensor sensing output rotation speed of the fan pulse signal, the present invention is obviously more economical, and is not subjected to the influence of rotation speed of the fan control mode compared to existing technology; in addition; owing to be in the fan power supply circuit rather than, therefore, can overcome prior art can't extract the rotation speed of the fan pulse signal when PWM modulates problem in the fan internal extraction.
Further, the rotation speed of the fan pulse signal that said extracted goes out also need pass through step 22) shaping is so that obtain the logical signal of standard, and the method for shaping is more, repeats no more here.
The rotation speed of the fan pulse signal that above-mentioned shaping obtains is the logic level of standard, therefore, in step 23) further detect the waveform of the described signal that shaping obtains, and determine fan-status according to the waveform of described signal, the waveform of signal is normal low or normal height as described, determine that then fan breaks down, otherwise fan is normal, rotating speed state that can be definite according to the number of pulse in the waveform of described signal.
The following describes fan-status pick-up unit of the present invention, please referring to shown in Figure 5, fan-status pick-up unit of the present invention comprises with lower device:
Extraction element 51, input end links to each other with the fan power supply circuit, is used for extracting rotation speed of the fan pulse signal and output from the fan power supply circuit;
Apparatus for shaping 52, input end links to each other with extraction element 51, is used for the rotation speed of the fan pulse signal that extracts is carried out shaping and output;
Pick-up unit 53, input end links to each other with apparatus for shaping 52, is used to detect the waveform of the signal of apparatus for shaping 52 outputs, and determines the corresponding state of fan according to the waveform of described signal.
Please referring to shown in Fig. 6 a, as extracting the rotation speed of the fan pulse signal, only need a coupled circuit that rotation speed of the fan pulse signal coupling output is got final product, unlike the prior art, rotation speed of the fan pulse signal of the present invention is not in the fan circuit internal extraction.But in the fan power supply circuit extraction, for example described coupled circuit is connected on the fan power supply end, alternating signal in the fan power supply circuit is coupled into voltage signal and output by described coupled circuit, in the present embodiment, described coupled circuit is the differentiating circuit of being made up of first resistance R 1 and first capacitor C 1, wherein this first resistance R 1 and first capacitor C 1 are connected between fan power supply end and the voltage reference points, this first resistance C1 connects voltage reference points, alternating signal in the fan power supply circuit is exported after by described first capacitive coupling, be understood that obtaining the rotation speed of the fan pulse signal based on coupling also has multiple variation, here enumerate no longer one by one, shown in Fig. 6 a, alternating signal in the fan power supply circuit is by above-mentioned coupled circuit coupling output, output waveform is seen shown in Fig. 6 b, in the signal of output rotation speed of the fan pulse signal a is arranged not only, also have two disturbing pulse signal b (being the noise signal of the inversion signal formation of fan control signal) to be coupled to B point output terminal.
As above-mentioned; coupled circuit by above-mentioned differentiating circuit composition; a also is superimposed with two undesired signal b simultaneously at output rotation speed of the fan pulse signal; this undesired signal b of B point output terminal is the differential signal of Qb end signal inversion signal among Fig. 6 b; in order to distinguish with the differential signal that relates to later; we claim that this signal is first differential signal; described Qb end is the rotation speed of the fan signal input end; described Qb signal is the rotation speed of the fan control signal; can be pwm signal (by dutycycle control speed governing); or high-low level, the oxide-semiconductor control transistors switch is realized the control to fan start and stop or rotating speed.In order to eliminate described disturbing pulse b,, then the two superimposedly just can have been eliminated this first differential signal as long as extract the differential signal of a Qb signal.Therefore, we can add another coupled circuit in circuit, please referring to shown in Fig. 7 a, this coupled circuit is the differentiating circuit that second resistance R 2 and second capacitor C 2 are formed, be connected between fan control signal input end and the voltage reference points, wherein second resistance R 2 connects voltage reference points, the output terminal of described coupled circuit links to each other with the alternating signal output terminal, fan control signal outputs to first capacitor C, 1 output terminal after by second capacitor C, 2 differential and the just described undesired signal b stack of described first differential signal just can be eliminated described undesired signal b like this, above-mentioned present embodiment coupled circuit only is described with the simplest differentiating circuit, in fact described coupled circuit also has multiple version, does not repeat them here.Please refer to Fig. 7 a, C2, R2 forms a coupled circuit, fan control signal just Qb signal (seeing shown in Fig. 7 b) obtains the differential of Qb signal through second capacitor C 2, we claim that this differential signal is second differential signal, the waveform of output is shown in Fig. 7 d, exporting described second differential signal of C point output to B point output terminal also is the first coupled circuit voltage signal output end (being B point among Fig. 7 a), then be D point output waveform signals after second differential signal stack of first differential signal in the B point output waveform (see among Fig. 7 c shown in the b) and the output of C point, only stay rotation speed of the fan pulse signal (shown in Fig. 7 e) at this moment.
The rotation speed of the fan pulse signal extracts, and also it will be shaped as the logical signal of standard.Shaping is a mode relatively more commonly used in the communication, is used for wave form varies, and the actual circuit of realizing is a lot, has proposed a kind of simple circuit below.
Please refer to Fig. 8 a, the apparatus for shaping of present embodiment comprises an operational amplifier, one the 3rd resistance R 3, one the 4th resistance R 4 and the 5th resistance R 5, with reference to figure 7a, when D holds the average voltage of the signal of output is 0, if the shaping operational amplifier of back, then must with dual power supply (the amplifier input end of the power supply of single supply be not advise being 0), if, then must make operational amplifier inverting input (V-) input be about the VCC supply voltage of mid point with the operational amplifier of single supply.So, the VCC fan power supply voltage that first resistance R 1 among Fig. 7 a, second resistance R 2 connect an end reconfiguration to 1/2 of voltage reference points.In addition, owing to first resistance R 1, second resistance R 2 are in parallel, so can replace with one the 3rd resistance R 3.The circuit such as Fig. 8 a that simplify, R3, R4, R5 are potential-divider network, obtain about 1/2 VCC supply voltage at the V+ end, and R3//(R4+R5)=R1//R2, could guarantee that like this RC constant is constant among Fig. 7 a, the circuit AC characteristic of Fig. 8 a also just is equivalent to Fig. 7 a, but the DC level of output is lifted to 1/2 VCC.
The wave shaping part, the quiescent voltage of V+ is about 1/2 VCC, and the quiescent voltage of V-is than V+ slightly high (described V-voltage is the standard comparative voltage).Like this when no fan rotational speed pulse signal operational amplifier output be exactly low level, when the rotation speed of the fan pulse signal arrived, V+ voltage can be higher than V-, with reference to the output waveform on the right of the figure 8b.Like this, the waveform of operational amplifier output is exactly the rotation speed of the fan pulse signal after the shaping, by a pick-up unit, detect the waveform of the signal of shaping unit shaping output, and determine the corresponding state of fan according to the waveform of described signal, it have or not the commentaries on classics that shows fan and do not change, the height of frequency then shows the speed of rotation speed of the fan.When the present invention used above-mentioned method and device to detect fan-status, compared to existing technology, it is easier that fan-status detects, and realizes that circuit is then simpler, and its cost is also lower.
In addition, the starting point that the present invention extracts the rotation speed of the fan pulse signal is to eliminate the undesired signal of rotation speed of the fan control signal formation directly to extract the rotation speed of the fan pulse signal from the fan power supply circuit, in the realization of signal extraction and shaping, above-mentioned schematic diagram is a kind of typical case and relative simple implementation method, and is not unique.
The above only is a possible embodiments of the present invention, and is non-so promptly limit to interest field of the present invention, and the equivalence that all utilizations instructions of the present invention and accompanying drawing content are done changes, and all reason is with being contained in the claim scope of the present invention.
Claims (8)
1, a kind of fan-status detection method is characterized in that, this method may further comprise the steps:
A) from fan power supply circuit extraction rotation speed of the fan pulse signal;
B) the described rotation speed of the fan pulse signal that extracts is carried out shaping;
C) detect the waveform of the signal that described shaping obtains, and determine the corresponding state of fan according to the waveform of described signal.
2, fan-status detection method according to claim 1 is characterized in that, described step a) further may further comprise the steps:
A1) with the coupling of the alternating signal in fan power supply circuit output, described alternating signal is superimposed with the inversion signal of rotation speed of the fan pulse signal and rotation speed of the fan control signal;
A2) rotation speed of the fan control signal coupling is exported to the output terminal of above-mentioned alternating signal, with the inversion signal of offsetting the rotation speed of the fan control signal that superposes in the described alternating signal through coupling output produce noise signal.
3, fan-status detection method according to claim 2 is characterized in that, described rotation speed of the fan control signal is PWM (width modulation) signal or high-low level signal.
4, a kind of fan-status pick-up unit is characterized in that, comprising:
Extraction element, input end links to each other with the fan power supply circuit, is used for extracting rotation speed of the fan pulse signal and output from the fan power supply circuit;
Apparatus for shaping, input end links to each other with extraction element, is used for shaping of rotation speed of the fan pulse signal and output to extracting;
Pick-up unit, input end links to each other with apparatus for shaping, is used to detect the waveform of the signal of apparatus for shaping output, and determines the corresponding state of fan according to the waveform of described signal.
5, fan-status pick-up unit according to claim 4 is characterized in that, described extraction element comprises:
First coupled circuit is used for the alternating signal coupling output with the fan power supply circuit, and described alternating signal is superimposed with the inversion signal of rotation speed of the fan pulse signal and rotation speed of the fan control signal;
Second coupled circuit, its output terminal links to each other with the first coupled circuit signal output part, be used for rotation speed of the fan control signal coupling output, produce the noise signal of rotation speed of the fan control signal, offset the noise signal that the inversion signal by the rotation speed of the fan control signal of described first coupled circuit output produces.
6, fan-status pick-up unit according to claim 5 is characterized in that, described first coupled circuit is the differentiating circuit that first electric capacity (C1) and first resistance (R1) are formed, and is connected between fan power supply end and the voltage reference points.
7, fan-status pick-up unit according to claim 6 is characterized in that, described second coupled circuit is the differentiating circuit that second electric capacity (C2) and second resistance (R2) are formed, and is connected between rotation speed of the fan signal input end and the voltage reference points.
8, fan-status pick-up unit according to claim 7, it is characterized in that, described apparatus for shaping is an operational amplifier, described operational amplifier one input end wind-receiving fan rotational speed pulse signal output terminal, another input termination standard comparative voltage is used for described rotation speed of the fan pulse signal is shaped to the standard logic signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031479022A CN100337116C (en) | 2003-06-25 | 2003-06-25 | Fan condition detecting method and apparatus therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031479022A CN100337116C (en) | 2003-06-25 | 2003-06-25 | Fan condition detecting method and apparatus therefor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1566960A true CN1566960A (en) | 2005-01-19 |
| CN100337116C CN100337116C (en) | 2007-09-12 |
Family
ID=34472079
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB031479022A Expired - Fee Related CN100337116C (en) | 2003-06-25 | 2003-06-25 | Fan condition detecting method and apparatus therefor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100337116C (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101281057B (en) * | 2007-04-02 | 2011-06-22 | 鸿富锦精密工业（深圳）有限公司 | Airflow detecting device |
| CN102226814A (en) * | 2011-03-30 | 2011-10-26 | 天津瑞能电气有限公司 | Method for measuring rotating speed of main shaft of wind turbine generator system and mechanism for detecting rotating speed pulse |
| CN103198609A (en) * | 2013-04-16 | 2013-07-10 | 常州工学院 | Direct-current fan failure alarm circuit |
| CN103233904A (en) * | 2013-05-13 | 2013-08-07 | 株洲南车时代电气股份有限公司 | Fan state feedback control device and method thereof |
| CN103486068A (en) * | 2013-09-16 | 2014-01-01 | 福建星网锐捷网络有限公司 | Smart fan and control detecting method and device for smart fan |
| CN106124841A (en) * | 2016-06-29 | 2016-11-16 | 无锡蕴能科技有限公司 | The fan testing circuit of a kind of Intelligent charger for electric bicycle and detection method |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61167389A (en) * | 1985-01-18 | 1986-07-29 | Nec Corp | Motor fan malfunction detecting mechanism |
| JPS6219616A (en) * | 1985-07-19 | 1987-01-28 | Hanshin Electric Co Ltd | Detecting circuit of fan rotating speed for burning control device |
| CN87205307U (en) * | 1987-11-24 | 1988-10-12 | 北京航天工业部第七○一研究所 | Synthetic measuring device for electric fan properties |
| CN2375968Y (en) * | 1999-04-02 | 2000-04-26 | 点晶科技股份有限公司 | Speed detecting circuit device for brushless fan |
| CN1116610C (en) * | 1999-10-20 | 2003-07-30 | 神达电脑股份有限公司 | Rotation speed measuring circuit for electric fan |
-
2003
- 2003-06-25 CN CNB031479022A patent/CN100337116C/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101281057B (en) * | 2007-04-02 | 2011-06-22 | 鸿富锦精密工业（深圳）有限公司 | Airflow detecting device |
| CN102226814A (en) * | 2011-03-30 | 2011-10-26 | 天津瑞能电气有限公司 | Method for measuring rotating speed of main shaft of wind turbine generator system and mechanism for detecting rotating speed pulse |
| CN103198609A (en) * | 2013-04-16 | 2013-07-10 | 常州工学院 | Direct-current fan failure alarm circuit |
| CN103233904A (en) * | 2013-05-13 | 2013-08-07 | 株洲南车时代电气股份有限公司 | Fan state feedback control device and method thereof |
| CN103233904B (en) * | 2013-05-13 | 2015-12-02 | 株洲南车时代电气股份有限公司 | A kind of fan-status feed back control system and method thereof |
| CN103486068A (en) * | 2013-09-16 | 2014-01-01 | 福建星网锐捷网络有限公司 | Smart fan and control detecting method and device for smart fan |
| CN106124841A (en) * | 2016-06-29 | 2016-11-16 | 无锡蕴能科技有限公司 | The fan testing circuit of a kind of Intelligent charger for electric bicycle and detection method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100337116C (en) | 2007-09-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1238962C (en) | Drive circuit for single-phase motor and drive method for single-phase motor | |
| CN1282399C (en) | Method of detecting an arc in a glow discharge device and apparatus for controlling a high-frequency arc discharge | |
| CN1957524A (en) | Brushless motor drive control circuit and brushless motor device using the same | |
| CN100337116C (en) | Fan condition detecting method and apparatus therefor | |
| CN101030747A (en) | Device for driving a single phase motor | |
| CN1831550A (en) | Contactless detection device of display panel | |
| CN101030441A (en) | Method and apparatus for reading and sampling data of DDR and DDR2 memory controller | |
| CN105760016A (en) | Touch control panel and driving method thereof | |
| CN1913333A (en) | Drive device of fan moter | |
| CN1610833A (en) | Test machine for testing an integrated circuit with a comparator | |
| CN101059547A (en) | Diagnostic signal processor | |
| CN101033750A (en) | Fan system and detecting device thereof | |
| CN1300931C (en) | Motor drive apparatus | |
| CN103135873A (en) | Touch sensing system and operation method thereof | |
| CN1728235A (en) | Device and method for detecting sound type | |
| CN101325391B (en) | Motor control apparatus | |
| CN1603838A (en) | Rotation detecting device | |
| CN201340273Y (en) | Automobile direction sensor | |
| CN2842559Y (en) | General series-bus concentrator | |
| CN206379874U (en) | Overcurrent protection peripheral circuit and electrical equipment | |
| CN108227541A (en) | A kind of discontinuous analog difference signal frequency and phase acquisition method | |
| CN2375968Y (en) | Speed detecting circuit device for brushless fan | |
| CN101051830A (en) | Noise comparison circuit of electric grid synchronous single head | |
| CN1165449A (en) | Clock signal generating apparatus and clock signal generating method | |
| CN215934751U (en) | Long-distance speed control system of direct-current brushless motor of fan |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20070912 Termination date: 20150625 |
|
| EXPY | Termination of patent right or utility model |