200912218 九、發明說明： 【發明所屬之技術領域】 本發明係錢-種具自動風向決策之 耗並r室内空氣流動效率、不需額外之二 向感測為、嘴音低及誤判率低等功效。 【先前技術】 參閱第-圖’此為傳統之抽風機9G，係財_ 可：換「關」、「吸氣」及 90部具有下列之缺點： 電力桃高且料高。以往抽風機9q係以人為決策 =識機90為排氣，且外界之自然風之方向亦相同時 =㈣’電力消耗較低。然而，當自然風向改變（如 ^二圖所示），該抽風機⑽因為轉動方向與自然風向逆向（風 而產生極㈣音，也因逆向_係，必須消 耗更大的電流，失去強制空氣流動的本意。 ⑵沒有自動_設計。傳統抽風機無法感崎設場所的 :=無:自動改變抽風機之轉動方向，假設要能自動改變 哭作咸卿而額外在原有之抽風機前後加裝風壓計或風向感測 :=ΓΓ (例如:充滿油煙之廚房、充滿木屑粉 充滿農作物粉塵之農產品倉庫等等），極易因 油煙、粉塵等影響，使風壓計之壽命大幅縮短；因此，額外加 200912218 風壓。十或風向感測器來當作感測源之作法既不美觀也不實 用。 、 [,]易誤判。通吊要侧室内與室外之風向，可採用風壓 計來判斷’但是，室内之風壓可能因為室溫、陳設物件、室内 風扇或其他自戶（若開啟可能有空氣流動）而影響，而室外之風 [更可城自然改變之風向、風速、天氣變化而影響，因此， 既不精碟也不實用；即使綱風壓計來判斷，極易受到外界干 擾而誤判’而且不_裝設位置亦可能導致不—樣的判斷結 果’極易造成誤判。 因此，有必要研發新技術以解決上述缺點。 【發明内容】 肝本㈣之主要目的，在於提供一種具自動風向決策之抽風 裝置，其節省電力雜並提升室内空氣流動效率。 本發明之次-目的，在於提供一種具自動風向決策之抽風 裝置，其*需額外之風細或風向感測器。 在於提供-雜自動如絲之抽風 本發明之又一目的， 裝置’其噪音低。 本發批再-㈣，在於触—祕自_喊策之抽風 裝置，其誤判率低。 本發明係提供-種具自動風向決策之抽風裝置，其包括： -風扇，係介於—第—空間及一第二空間之間，該^至 >具有-停止模式、-第—風向模式及一第二風向模式；當該 200912218 風扇在該第-風向模式，其風向由該第—空間吹至該第二空 間’當該風屬在該第二風向模式，其風向由該第二空間吹至該 第一空間； -電流感測部，係用以即時量測該風扇之電流變化，並得 到一風扇電流訊號； 一切換部’侧以控編風A於第-風向模式及-第二風 向模式之間切換； 一電源輸人部’ _讀人—交流電源，其具有預定之工 作電壓及一主要工作頻率； 控制部’ _以處理賴扇電流職，再經由傅利葉分 析而得到賴扇電流看4制魅要轉頻树之複數個 電流峰值；餅財職之電騎健-數學後與一參考 值比較，賴縣之電鱗值上升且大麟參考值，則控 制該切換部對該風扇進行f—風向模式及—第二風向模式之 間的切換。 本發明之上述目的與優點，雜從下述所選用實施例之詳 細說明與附圖中，獲得深入瞭解。 茲以下列實施例並配合圖式詳細說明本發明於後： 【實施方式】 參閱第四、第五、第六及第七圖，本發明係為一種具自動 風向決策之抽風裝置，其包括： —風扇10’係介於一第一空間71及一第二空間72之間， 200912218 該風扇1G至少具有-停止模式、—第—風向模式及—第二風 ^板式；當該風扇10在該第一風向模式時，其風向由該第— :間71吹至該第二空間72 ’當該風扇1〇在該第二風向模式 時，其風向由該第二空間72吹至該第一空間71 ; —電流感麟2G ’係肋即時量職闕1〇之電流變 化，並得到一風扇電流訊號I(t); 夂 —切換部4G，係用以控制該風扇1()於—停止模式、一第 風向模式及一第二風向模式之間切換； —電源輸人部60，係用以輸人—交流電源，其具有預定 之工作電壓及一主要工作頻率； 、^ w〜心，土咏风领电流訊號I(t)，再經由 傳利葉分析而得到該風扇電流訊號1⑴在對應該主要工作頻 ^時之複數個紐峰值；並將狀職之電流峰魅-數學運 异（例如：加總/平均）後與—來考 ^ 、 、>芩值比較，若該預定週期之電 ^值上升从於該參寺值，制該切換部40賴風扇10 進仃第-風向模式及第二風向模式之間的切換。 如此為本發明之具自動風向決策之抽風裝置。 當該風扇！0之扇葉受到來自相異方向的自然風力（如第 七圖所不由第二空間72指向第_介門α200912218 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to the consumption of automatic wind direction and the efficiency of indoor air flow, no additional two-way sensing, low mouth sound and low false positive rate. efficacy. [Prior Art] Refer to the figure - Figure 'This is the traditional exhaust fan 9G, which is _ _: change "off", "inhale" and 90 parts have the following disadvantages: Power peach high and high material. In the past, the exhaust fan 9q was based on human decision = the engine 90 was exhausted, and the direction of the natural wind outside was the same = (4) 'The power consumption was low. However, when the natural wind direction changes (as shown in Fig. 2), the exhaust fan (10) is reversed from the natural wind direction (the wind produces a polar (four) sound, and also because of the reverse _ system, it must consume more current and lose the forced air. (2) There is no automatic _ design. The traditional exhaust fan can not feel the location of the wind: = no: automatically change the direction of rotation of the exhaust fan, assuming that you can automatically change the crying of salty and additional before and after the original exhaust fan Wind pressure gauge or wind direction sensing: =ΓΓ (for example: kitchen filled with oil fume, warehouse of agricultural products filled with wood dust powder filled with crop dust, etc.), it is easy to reduce the life of the wind pressure meter due to the influence of soot, dust, etc. , plus the addition of 200912218 wind pressure. Ten or wind direction sensor as a sensing source is neither aesthetic nor practical. [,] easy to misjudge. Through the side and outdoor wind direction, can be used wind pressure gauge To judge 'But the indoor wind pressure may be affected by room temperature, furnishings, indoor fans or other households (if there may be air flow when opening), and the outdoor wind [more can change the city naturally It is affected by changes in wind direction, wind speed and weather. Therefore, it is neither practical nor practical; even if it is judged by the wind pressure gauge, it is highly susceptible to external interference and misjudged 'and not _ installation position may lead to no-like judgment result' It is easy to cause misjudgment. Therefore, it is necessary to develop new technologies to solve the above disadvantages. [Summary of the Invention] The main purpose of the liver (4) is to provide a draft device with automatic wind direction decision, which saves power and improves indoor air flow efficiency. A second object of the present invention is to provide an air extracting device with automatic wind direction decision, which requires an additional wind or wind direction sensor. It is a further object of the present invention to provide a wind-exhausting air. The noise is low. This batch is again - (4), in the touch-secret _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - between the first space and a second space, the ^ to > has a - stop mode, a - first wind direction mode and a second wind direction mode; when the 200912218 fan is in the first wind In the mode, the wind direction is blown from the first space to the second space. 'When the wind belongs to the second wind direction mode, the wind direction is blown from the second space to the first space; - the current sensing part is used Instantly measuring the current change of the fan and obtaining a fan current signal; a switching part 'side to control the wind A to switch between the first wind direction mode and the second wind direction mode; a power input part ' _ read Human-AC power supply, which has a predetermined working voltage and a main operating frequency; the control unit ' _ is used to process the fan current, and then the Fourier analysis is used to obtain the plurality of current peaks of the frequency tree. After the mathematics is compared with a reference value, the electric scale value of Lai County rises and the reference value of the Dalin increases, then the switching part is controlled to perform the f-wind direction mode and the second wind direction mode of the fan. Switch between. The above objects and advantages of the present invention are obtained from the detailed description of the preferred embodiments described herein. The present invention will be described in detail with reference to the following embodiments in conjunction with the accompanying drawings: FIG. 4, FIG. 4, FIG. The fan 10' is interposed between a first space 71 and a second space 72, and the fan 1G has at least a stop mode, a first wind direction mode, and a second wind plate type; when the fan 10 is in the In the first wind direction mode, the wind direction is blown by the first to the second space 72'. When the fan 1 is in the second wind direction mode, the wind direction is blown by the second space 72 to the first space. 71; —Current Sense 2G' ribs instantaneous load 阙 1〇 current change, and get a fan current signal I (t); 夂 - switching part 4G, used to control the fan 1 () in the - stop mode Switching between a first wind direction mode and a second wind direction mode; - a power input unit 60 for inputting a human-AC power source having a predetermined operating voltage and a main operating frequency; , ^ w ~ heart, earth The hurricane leads the current signal I(t), which is then obtained by the analysis of the leaves. The fan current signal 1(1) is at the multiplicity of peaks corresponding to the main working frequency; and the current peak of the current position is mathematically different (for example: totaling/averaging) and then - to test ^, , > In comparison, if the electric value of the predetermined period rises from the value of the temple, the switching unit 40 is caused to switch between the first wind direction mode and the second wind direction mode. Thus, the present invention is an air drafting device with automatic wind direction decision making. When the fan! The blade of 0 is subjected to natural winds from different directions (as in Figure 7, the second space 72 is not directed to the first door α)
弟卫間71的假想線箭頭），會 產生相對之阻力；械使顯1G 達消耗電流也會隨之增加，且、sn斤而扭力“則馬 曰丨現之《加且通風效果不佳，·本發明以此 200912218 透k風扇10之馬達消耗電流的變化來感應出當時取 之扇葉的受風狀態；若綠值超過預設值太多，則判斷目二風 扇10之風向與自然風相反，並由控制部50立即下達反轉的命 令j過該切換部4〇來控制該風扇10進行反轉；相反的，: 果電流值小於或是接近預設值，則判斷風向無衝突，並保持當 時狀態。 w 〇簡言之，如第四圖所示，主要係利用擷取該風扇之電流訊 號至-控制器’再判斷是否與外界之風向相反，一旦相反，則 輸出一切換信號給該風扇以切換其風向。 、 而本發明之實際運作，在此詳述如下： 關於硬體部分： 該電流感測部20係採用阿列格羅（AUegr〇)公司的 ACS704ELC 005電流感測器，此晶片為一線性之電流感測器。 該切換部40可以配合繼電器41(如第五圖所示)控制該風 扇10於停止模式、第-風向模式與第二風向模式之間進行切 換。 該控制部50之運算核心係採用單晶片微控器，例如：犯油The imaginary line arrow of the brother-in-law 71 will produce a relative resistance; the mechanical output will increase the current consumption of the 1G, and the sn-pulse and the torque will be "the sound of the horse is not good," The invention uses the change of the motor current consumption of the 200912218 through the k-fan 10 to sense the windy state of the blade taken at that time; if the green value exceeds the preset value too much, the wind direction and the natural wind of the second fan 10 are judged. On the contrary, the control unit 50 immediately issues the reverse command j through the switching unit 4 to control the fan 10 to reverse; on the contrary, if the current value is less than or close to the preset value, it is determined that the wind direction has no conflict. And keep the state at that time. w 〇 In short, as shown in the fourth figure, the main purpose is to take the current signal of the fan to the controller and then judge whether it is opposite to the outside wind. If it is the opposite, it outputs a switching signal. The fan is switched to its wind direction. The actual operation of the present invention is described in detail below: About the hardware portion: The current sensing unit 20 uses Ailegro's ACS704ELC 005 current sensing. Device, this chip is Linear current sensor The switching unit 40 can control the fan 10 to switch between the stop mode, the first wind direction mode and the second wind direction mode in cooperation with the relay 41 (as shown in the fifth figure). The computing core uses a single-chip microcontroller, such as: oil
Speed 8051 FLASH MCIKC8051F021)。 該電濾輸入部60可再包括一變壓器61(如第五及第六圖 所示）’該變壓器61係用以將與工作電壓成正比之電壓訊號縮 小/放大至與該電流感測部20之風扇電流訊號i(t)相近之程 200912218 度，以利後續之避免誤判之用。 止 菖然’ δ亥電源輸入部60亦可用 以控制該風扇1〇啟動/停 此外’本案可再包括： 一誤判分析部30,仙轉理贼週期的風扇電流訊號 I⑴’亚魏與該工作成正比之 / 減後付到-U目對變化量，將該電流變化量當作控制部別 之判斷來源，進而提高本發明之可靠性。 至少一狀態顯示元件81(如第五圖所干Speed 8051 FLASH MCIKC8051F021). The filter input unit 60 can further include a transformer 61 (as shown in the fifth and sixth figures). The transformer 61 is configured to reduce/amplify the voltage signal proportional to the operating voltage to the current sensing unit 20 The fan current signal i(t) is similar to 200912218 degrees, in order to facilitate the subsequent avoidance of misjudgment.菖然然' δHai power input unit 60 can also be used to control the fan 1〇 start/stop. In addition, the case can further include: a false positive analysis unit 30, the fan current signal I(1)' of the thief cycle and the work It is proportional to/reduced and then paid to the -U mesh to the amount of change, and the current change amount is used as a source of judgment of the control unit, thereby improving the reliability of the present invention. At least one state display element 81 (as shown in the fifth figure)
口所不，例如為三顆LED 燈），其用以顯不出本案之狀態。 一敏感度調整元件82，係用以改變該參考值。假設原本 設定參考值為5單位，但發社敏_猶繁）或是太不敏 感（不易城)時’則可以將參考值調低或調高，如 扇10之敏感度適中。 關於軟體方面： 於核心（即該控制部5〇)中係以傅立葉分析來估算預定週 期之電流值’藉喊得更正確之錄，減少系統糊之機合。 …而誤齡_理是透過縣放Α||進行，主要係對訊號進 行濾波 '放大；此為考慮公共供電之電流訊號值並非穩定保持 於110伏特，而會因時間及地點不同有所變動，進而能影塑 電流訊號的穩定性；因歧懸器之二次條得工作電壓3 200912218 將此工作電壓縮小/放大至與該電流感測部輸出訊號相近，透 =相減後之差值’就可以得到_個電流相對變化量；以此變化 置為判斷依據’以減少系統之誤判率。 本發明除了峨判分析料行工作電流峨除雜訊作業 外’另外以軟體方式(於該控制部内）進行數位訊號處理/、 至於貝際里出之數據方面，係以電流探棒加上示波器來量 測電流感·的輸出（如“騎示），再_快速傅立葉轉換 加tF〇urierTransf〇rm，簡稱fft)來進行電流訊號的頻譜 刀析可以發現電流訊號為一個_z的弦波訊號(顯示於第九 圖中大約_z處之物，亦即本實施辦之主要工作頻率為 60Hz至於其餘頻率位置所示較小波形者均為譜波）。 ”人田風扇10叉負載時，電流變化量最大也在60Hz的 位置(如第/及第十1所示，其中第十圖之第-曲線L1表示 逆向風，第：曲線L2表示無風，第三曲線U表示順向風；至 於第:ffi中的波形N代表無風，波形f代表順向風，波形r 代表疋向風），所W可姻傅稱分析指出剛z的電流成份 大小’並以此成份大小為觸依據。 本發明舉實例驗證說明如下： 一假β又風扇10由第一空間71吹向第二空間似如第七圖所 示’處於排風狀態），模擬外來風向之順向與反向所測試之结 果攸第十一圖可明顯看出，第四曲線L4為當風向衝突時之 200912218 電流大小值；第五曲線L5為當風向相同時之電流大小值，由 風向衝突切換至風向相同之狀態下，風扇可以減少約0. 2安培 的電流，可節省約22瓦的電力消耗，並提升室内空氣流動。 假設風扇改由第二空間72吹向第一空間71(圖面未示風 扇之吹風方向，但處於吸風狀態）。同樣模擬外來風向之順向 與反向測試之結果，如第十三圖所示；其中第六曲線L6為兩 者風向衝突時之電流大小值；而第七曲線L7為兩者風向相同 時之電流大小值；由風向衝突切換至風向相同之狀態下，風扇 則可以減少約G. 16安培的電流，可節轉約17瓦的電力消 耗’並提升室内空氣流動。 由以上測試結果可知，若能使風扇具備自動決策風向的能 力；以本職環境而言，至何以節省約16瓦的功率消耗， 與風扇額定雜1流G. 8安培來崎，大約可㈣省2_電 力消耗，叫能的觀點來看，於抽顺上增加自誠策風向的 能力’其效益非常高。 本發明並舉以下實驗過程說明： 根據妹得之電流值，透顯立葉分析⑽u如 :二進二數位1爾理’以40 _期蝴判斷值;測 試步驟如= 咖擬自麵向’树邮進行測試，測 [a] 將控制器連結财發明之風扇上 ’並確認無誤。 200912218 [b] 開啟電源’此時本發明之風扇設為排風狀態。 [c] 將電風扇置於本發明之風扇的風向相異處: ⑷開啟電風扇電源，模擬_風向相異之自然風。 [e]觀察控制器風向狀態燈。 ⑴右本發明找顧物觀向，财觀察風向狀態 燈。 [g]若無誤判的情況發生，則關閉電風扇電源。 ω再將電風扇置於本發明之風扇風向相異處。 [1]依序再由d至g項進行測試。 當電風扇置於距離本發明之風扇的30公分處，控制器會 依據電風扇風向進行靖無策本發明之風献倾向，試驗 結果成功驗證本作品為一可行之方案。 綜上所述，本發明之優點及功效可歸納為： [1]節省電力消耗並提升室内空氣流動效率。簡言之，本 發明設置電流感測部、糊分析部、切換部以及控制部，這些 結構相互配合，可感測風扇與外界風向相衝突或是風向相同= 進-步自動將風扇切換至外界風向相同之轉動模式，可有效節 省電力消耗，而以較佳強制空氣流動的效率，提升室内空氣节 動效率。 [2 ]不需額外之職計或風向感測||。本發明直接感測風 扇之風扇電流訊號，進而以數學式換算成電流峰值，再以電产 13 200912218 峰值與電源輸入部之參考值進行比較，即可直接控制風扇之轉 動方向，不需額外裝設風壓計或風向感測器，也不會有感測計 /器破壞整體美觀或是因受外力而損傷的情況。 [3 ]噪音低。本發明係可避免風扇之風向與自然方相反之 逆風炀开>，因此，風扇運轉時之噪音相當低。 [4]誤判率低。本發明透過運算放大器對電流訊號進行濾 波、放大；·触躺職與觀^^^摘轉並縮小之 交流電訊號作械運算後之姆魏量；可㈣部當做邦 斷依據，以減少系統之誤判率。 以上僅是藉由較佳實施例詳細說明本發明，對於該實施例 所做的任何簡單修改與變化，皆不脫離核之精神與範圍。 由以上詳細說明，可使熟知本項技藝者明瞭本發明的確可 達成前述目的’實已符合專利法之規定，爰提出發明專利申請。 【圖式簡單說明】 第一圖係習用結構之應用示意圖 第二圖係制結構之第—動作狀態示意圖 第二圖係習用結構之第二動作狀態示意圖 第四圖係本發明之動作流程示意圖 200912218 第五圖係本發明之主要結構示意圖 第六圖係本發明之應用例之示意圖 第七圖係本發明之應用例之平面示意圖 第八圖係本發明之電流訊號之示意圖 第九圖係本發明之電流訊號經快速傅立葉轉換結果之示意圖 第十圖係本發明之電流訊號變化量結果之示意圖 第十一圖係本發明之電流訊號變化量經快速傅立葉轉換結果 之示意圖 第十二圖係本發明之排風狀態電流消耗之示意圖 第十三圖係本發明之吸風狀態電流消耗之示意圖 【主要元件符號說明】 10風扇 30誤判分析部 41繼電器 6〇電源輸入部 71第一空間 81狀態顯示元件 90抽風機 Kt)風扇電流訊號 L2第二曲線 L4第四曲線 L6第六曲線 20電流感測部 40切換部 50控制部 61變壓器 72第二空間 82敏感度調整元件 91控制元件 L1第一曲線 L3第三曲線 L5第五曲線 L7第七曲線The mouth is not, for example, three LED lights), which is used to show the state of the case. A sensitivity adjusting component 82 is used to change the reference value. If the original reference value is 5 units, but it is too sensitive (not easy to use), then the reference value can be lowered or increased. For example, the sensitivity of the fan 10 is moderate. Regarding the software aspect: In the core (that is, the control unit 5〇), the Fourier analysis is used to estimate the current value of the predetermined period, and the more accurate recording is made, which reduces the system paste. ...and the age of _ is based on the county's Α||, mainly to filter the signal 'amplification; this is the value of the current signal considering the public power supply is not stable at 110 volts, but will vary due to time and place In turn, the stability of the current signal can be imaged; the operating voltage of the secondary strip of the suspension is 3 200912218. The operating voltage is reduced/amplified to be close to the output signal of the current sensing unit, and the difference is subtracted 'You can get _ a relative change in current; use this change as a basis for judgment' to reduce the false positive rate of the system. In addition to the analysis of the operating current of the analysis, the noise removal operation is performed separately. In addition, the digital signal processing is performed in the software mode (in the control unit), and the data in the field is extracted by the current probe and the oscilloscope. Measuring the current sense output (such as "riding the display", then _ fast Fourier transform plus tF〇urierTransf〇rm, referred to as fft) for the spectrum analysis of the current signal can find the current signal as a _z string signal ( The object shown in the ninth figure is about _z, that is, the main operating frequency of the implementation is 60 Hz, and the smaller waveforms shown in the remaining frequency positions are spectral waves.) "The field fan 10 fork load, current The maximum amount of change is also at the position of 60 Hz (as shown in the first and the tenth, wherein the first curve of the tenth graph represents the reverse wind, the first curve: the curve L2 indicates no wind, and the third curve U indicates the forward wind; The waveform N in ffi represents no wind, the waveform f represents the forward wind, and the waveform r represents the forward wind. The analysis of the current component of the steel is based on the magnitude of the current component of the z. The verification verification example of the present invention is as follows: A fake β and fan 10 are blown from the first space 71 to the second space as shown in the seventh figure, which is in the exhaust state, and simulates the forward and reverse directions of the external wind direction. The results can be clearly seen in the eleventh figure. The fourth curve L4 is the current magnitude of 200912218 when the wind direction conflicts; the fifth curve L5 is the current magnitude when the wind direction is the same, and the wind direction conflicts to the same state of the wind direction. The fan can reduce the current by about 0.2 amps, which can save about 22 watts of power consumption and increase indoor air flow. It is assumed that the fan is blown by the second space 72 toward the first space 71 (the direction of the blower of the fan is not shown in the drawing, but it is in the suction state). Similarly, the results of the forward and reverse tests of the external wind direction are simulated, as shown in Fig. 13; wherein the sixth curve L6 is the current magnitude when the wind direction conflicts; and the seventh curve L7 is the same when the wind direction is the same. The current magnitude value; when the wind direction conflicts to the same direction, the fan can reduce the current of about G. 16 amps, which can save about 17 watts of power consumption' and increase the indoor air flow. From the above test results, it can be known that if the fan can have the ability to automatically determine the wind direction; in terms of the local environment, how to save about 16 watts of power consumption, and the fan rated miscellaneous flow of G. 8 amps to Razaki, about (four) province 2_ Power consumption, from the point of view of energy, the ability to increase the self-satisfaction direction in the smoothing process's efficiency is very high. The invention also cites the following experimental process description: According to the current value of the sister, the transparent lobular analysis (10) u such as: two into two digits 1 erre 'to determine the value of 40 _ period butterfly; test steps such as = coffee to self-oriented 'tree mail Test and test [a] connect the controller to the fan of the invention and confirm it. 200912218 [b] Turn on the power. At this time, the fan of the present invention is set to the exhaust state. [c] Place the electric fan in the wind direction of the fan of the present invention: (4) Turn on the electric fan power supply to simulate the natural wind with different wind directions. [e] Observe the controller wind direction status light. (1) Right, the invention looks for the object, and the state of the wind is observed. [g] If there is no misjudgment, turn off the power to the fan. ω then places the electric fan in a different direction of the fan's wind direction. [1] Then test from d to g in order. When the electric fan is placed 30 cm away from the fan of the present invention, the controller will proceed according to the wind direction of the electric fan, and the test result successfully verifies that the work is a feasible solution. In summary, the advantages and effects of the present invention can be summarized as follows: [1] Saving power consumption and improving indoor air flow efficiency. Briefly, the present invention provides a current sensing unit, a paste analysis unit, a switching unit, and a control unit. These structures cooperate to sense that the fan is in conflict with the outside wind direction or the wind direction is the same = the step-by-step automatic switching of the fan to the outside The same rotation mode of wind direction can effectively save power consumption, and improve the efficiency of indoor air articulation with better efficiency of forced air flow. [2] No additional job or wind direction sensing ||. The invention directly senses the fan current signal of the fan, and then converts the current peak value into a mathematical formula, and then compares the peak value of the electric product 13 200912218 with the reference value of the power input portion, thereby directly controlling the rotation direction of the fan without additional installation. There is no wind pressure gauge or wind direction sensor, and there is no situation that the sensor/device destroys the overall appearance or is damaged by external force. [3] The noise is low. According to the present invention, the wind direction of the fan can be prevented from being reversed from the natural side, and therefore, the noise during operation of the fan is relatively low. [4] The rate of false positives is low. The invention filters and amplifies the current signal through the operational amplifier; the touch-week and the observation ^^^ are turned and reduced, and the AC signal is calculated after the mechanical operation; the (four) part is used as the basis of the state to reduce the system. False positive rate. The present invention has been described in detail with reference to the preferred embodiments of the present invention. From the above detailed description, it will be apparent to those skilled in the art that the present invention may indeed achieve the aforesaid purpose. BRIEF DESCRIPTION OF THE DRAWINGS The first figure is a schematic diagram of the application of the conventional structure. The second figure is the structure of the structure - the schematic diagram of the action state. The second diagram is the schematic diagram of the second action state of the conventional structure. The fourth figure is the schematic diagram of the action flow of the present invention 200912218 5 is a schematic view of an application of the present invention. FIG. 7 is a schematic view showing an application example of the present invention. FIG. 8 is a schematic view showing an application example of the present invention. FIG. 11 is a schematic diagram showing the result of the current signal variation of the present invention. FIG. 11 is a schematic diagram showing the result of the fast Fourier transform of the current signal variation of the present invention. FIG. Schematic diagram of the current consumption of the exhaust air state Fig. 13 is a schematic diagram of the current consumption of the suction state of the present invention [Description of main components] 10 Fan 30 error analysis unit 41 relay 6〇 Power input unit 71 First space 81 state display Component 90 exhaust fan Kt) fan current signal L2 second curve L4 fourth curve L6 sixth curve 20 current Sensing section 40 switching section 50 control section 61 transformer 72 second space 82 sensitivity adjusting component 91 control component L1 first curve L3 third curve L5 fifth curve L7 seventh curve