1310826 九、發明說明： 【發明所屬之技術領域】 本發明是有關於一種過濾系統與其過濾箱，且特別是 有關於一種空氣過濾系統與其過濾箱。 【先前技術】 在實驗室或是高科技工廠中，廢氣一般會伴隨著進行 實驗或是製造生產的過程而產生。廢氣必須經由過濾系統 過濾之後，才能排放於大氣中以避免造成環境污染。因此， 過濾系統與其過濾箱之設計改良乃成為近年來研發之重要 方向。 圖1為習知之一種過濾箱的側面示意圖。請參考圖1， 習知之過濾箱100包括外罩110、排風口 120、進風口 130、 過濾網140、偏心凸輪150與手把160。排風口 120與進風 口 130是連接於外罩110之相對兩側，而過濾網140具有 相對之排風面142與進風面144，且過濾網140之排風面 142是靠合於排風口 120上。此外，習知技藝會用手把160 帶動偏心凸輪150，以使偏心凸輪150推動過濾網140，而 讓過濾網140緊靠於排風口 120上。 圖1A為圖1之過慮網的立體不意圖。請參考圖1與 1A，過濾網140包括邊框146與過濾材質148，其中過濾 材質148是配置於邊框146内，並用於過濾廢氣。廢氣是 經由進風面144進入過濾材質148中過濾成乾淨的氣體 後，再經由排風面142而離開過濾網140。 一般而言，排風口 120會連接抽風機（未繪示），而進 6 .1310826 二 風口 130會連接至產生廢氣的機器設備（未繪示）。當抽風 機啟動時，廢氣會沿著進風口 130而進入外罩110並充滿 • 於整個外罩110之中。儘管大部分的廢氣是沿著路徑P1由 ' 進風面144進入過濾材質148中過濾，但是仍有部分廢氣 會沿著路徑P2而進入過濾網140與外罩110之間的缝隙S。 承接上述，由於廢氣在縫隙S中流動不易，所以當時 間一久，廢氣中的有害物質便會沉積在過濾網140之邊框 146上，其中這些有害物質可能為化學物質、有機材料或 鲁是核廢料等。當操作人員更換過濾網140時，便會觸碰到 邊框146上的有害物質，而影響到操作人員的身體健康。 此外，若過濾網140與排風口 120之密合程度不佳， 則位於縫隙S中的廢氣便會直接由邊框146與排風口 120 之間穿透出去。由於這部分的廢氣未經過濾材質148過濾 便排放到大氣之中，如此即會嚴重污染環境。 【發明内容】 • 有鑑於此，本發明之目的是提供一種過濾箱，其過濾 網之邊框不易沾附有害物質。 此外，本發明之另一目的是提供一種過濾系統，具有 . 較佳的過濾、效果。 為達上述或是其他目的，本發明提出一種過濾、箱，適 於過遽空氣，而過濾箱包括排風口、進風口、外罩、過濾、 網、連動裝置與導氣單元。排風口與進風口是連接於外罩 之相對兩侧，而過濾、網、連動裝置與導氣單元是配置於外 罩内，其中過濾網具有相對之排風面與進風面，而連動裝 7 • 1310826 . 置適於使過濾網之排風面靠合於排風口上。此外，導氣單 元是連接於過濾網之進風面與進風口之間。 ' 此外，為達上述或是其他目的，本發明另提出一種空 氣過滤系統，包括上述之過濾箱、抽風機、第一導風管與 第二導風管，其中第一導風管是連接於過濾箱之排風口與 抽風機之間，而第二導風管是連接過濾箱之進風口。 在本發明之一實施例中，上述之導氣單元可包括錐形 罩體與彈性伸縮管。錐形罩體具有相對之第一開口與第二 _ 開口，而第一開口靠合於過濾網之進風面上，且錐形罩體 自進風面向進風口方向漸縮。彈性伸縮管是連接於錐形罩 體之第二開口與進風口之間。此外，彈性伸縮管例如為蛇 腹管。 在本發明之一實施例中，上述之過濾箱更可包括定位 裝置。定位裝置是配置於外罩内，並適於使錐形罩體之第 一開口靠合於過濾網之進風面上。 在本發明之一實施例中，上述之定位裝置可包括第一 • 限位件、第二限位件以及彈性元件。第一限位件是配置於 外罩上，而第二限位件是配置於錐形罩體上，且彈性元件 是連接於第一限位件與第二限位件之間。此外，彈性元件 . 例如為彈簧。 在本發明之一實施例中，上述之連動裝置可包括偏心 凸輪與手把，其中偏心凸輪是配置於過濾網之進風面旁， 而手把是連接偏心凸輪，以帶動偏心凸輪推動過濾網。 綜上所述，在本發明之空氣過濾系統與其過濾箱中， 由於導氣單元可導引廢氣直接由過濾網之進風面進入過濾 8 • 1310826 網内過濾，因此廢氣中的有害物質不易沉積於過濾網上。 此外，當抽風機運作以過濾廢氣時，過濾箱是呈負壓狀態， 因此廢氣僅能沿導氣單元而進入過濾網内過遽，如此可大 幅減少廢氣外漏的情形。 為讓本發明之上述和其他目的、特徵和優點能更明顯 易懂，下文特舉較佳實施例，並配合所附圖式，作詳細說 明如下。 【實施方式】 圖2為依據本發明一實施例之過濾箱的側面示意圖。 請參考圖2，本發明之過濾箱200適於過濾空氣，特別是 過濾由實驗或工廠生產時伴隨產生的廢氣。過濾箱200包 括外罩210、排風口 220、進風230 口、過濾網240、連動 裝置250與導氣單元260。排風口 220與進風口 230是連 接於外罩210之相對兩側，而過濾網240、連動裝置250 與導氣單元260是配置於外罩210内，其中過濾網240具 有相對之排風面242與進風面244，而連動裝置250適於 使過濾網240之排風面242靠合於排風口 220上。此外， 導氣單元260是連接於進風口 230與過濾網240之進風面 244之間。 在本實施例中，過濾網240可包括邊框246與過濾材 質248，其中過濾材質248是配置於邊框246内，並適於 過濾廢氣。當廢氣由進風口 230進入過濾箱200中時，廢 氣並不會散佈於整個外罩210内部，而是沿著導氣單元260 往過濾網240的方向前進。當廢氣由進風面244進入過濾 9 1310826 材質248中而被過濾、成乾淨的氣體後，再經由排風面242 而離開過〉慮網240。1310826 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a filtration system and a filter box thereof, and more particularly to an air filtration system and a filter box thereof. [Prior Art] In laboratories or high-tech factories, exhaust gas is usually produced along with experiments or manufacturing processes. Exhaust gas must be filtered through a filtration system before it can be released into the atmosphere to avoid environmental pollution. Therefore, the design improvement of the filtration system and its filter box has become an important direction for research and development in recent years. Figure 1 is a schematic side view of a conventional filter box. Referring to FIG. 1, a conventional filter box 100 includes a housing 110, an air outlet 120, an air inlet 130, a filter 140, an eccentric cam 150, and a handlebar 160. The air outlet 120 and the air inlet 130 are connected to opposite sides of the outer cover 110, and the filter screen 140 has a corresponding exhaust surface 142 and an air inlet surface 144, and the air outlet surface 142 of the filter 140 is coupled to the air outlet 120. on. In addition, conventional techniques utilize the handle 160 to drive the eccentric cam 150 such that the eccentric cam 150 pushes the filter 140 and the filter 140 abuts against the vent 120. FIG. 1A is a perspective view of the filter mesh of FIG. 1. FIG. Referring to Figures 1 and 1A, the filter screen 140 includes a frame 146 and a filter material 148, wherein the filter material 148 is disposed within the frame 146 and is used to filter exhaust gases. The exhaust gas is filtered into a clean gas through the air inlet surface 144 into the filter material 148, and then exits the filter screen 140 via the exhaust surface 142. Generally, the exhaust port 120 is connected to an exhaust fan (not shown), and the inlet 6.1310826 air outlet 130 is connected to a machine (not shown) that generates exhaust gas. When the extractor is activated, exhaust gas enters the outer casing 110 along the air inlet 130 and fills the entire outer casing 110. Although most of the exhaust gas is filtered from the inlet surface 144 into the filter material 148 along the path P1, some of the exhaust gas enters the gap S between the filter 140 and the outer casing 110 along the path P2. In view of the above, since the exhaust gas does not easily flow in the slit S, harmful substances in the exhaust gas are deposited on the frame 146 of the filter 140 for a long time, and the harmful substances may be chemical substances, organic materials or nuclear waste. Wait. When the operator replaces the filter 140, the harmful substances on the frame 146 are touched, which affects the health of the operator. In addition, if the degree of adhesion between the filter screen 140 and the exhaust vent 120 is not good, the exhaust gas located in the slit S is directly penetrated between the frame 146 and the vent 120. Since this part of the exhaust gas is filtered into the atmosphere without filtering the filter material 148, it will seriously pollute the environment. SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a filter box in which the frame of the filter net is less likely to be contaminated with harmful substances. Further, it is another object of the present invention to provide a filtration system having better filtration and effects. To achieve the above or other objects, the present invention provides a filter, a box, which is suitable for passing air, and the filter box includes an exhaust vent, an air inlet, a cover, a filter, a mesh, a linkage, and a gas guiding unit. The air outlet and the air inlet are connected to opposite sides of the outer cover, and the filter, the net, the linkage device and the air guiding unit are disposed in the outer cover, wherein the filter net has a relative exhaust surface and an air inlet surface, and the linkage device 7 • 1310826. Suitable for the exhaust side of the filter to fit on the exhaust vent. In addition, the air guiding unit is connected between the air inlet surface and the air inlet of the filter. In addition, in order to achieve the above or other purposes, the present invention further provides an air filtering system comprising the above filter box, an exhaust fan, a first air guiding duct and a second air guiding duct, wherein the first air guiding duct is connected to The air outlet of the filter box is connected with the exhaust fan, and the second air duct is connected to the air inlet of the filter box. In an embodiment of the invention, the air guiding unit may include a conical cover and an elastic telescopic tube. The tapered cover has a first opening and a second opening, and the first opening abuts against the air inlet surface of the filter, and the tapered cover tapers from the air inlet toward the air inlet. The elastic bellows is connected between the second opening of the conical cover and the air inlet. Further, the elastic bellows is, for example, a bellows tube. In an embodiment of the invention, the filter box described above may further comprise a positioning device. The positioning device is disposed in the outer cover and is adapted to abut the first opening of the tapered cover against the air inlet surface of the filter. In an embodiment of the invention, the positioning device may include a first • a limiting member, a second limiting member, and an elastic member. The first limiting member is disposed on the outer cover, and the second limiting member is disposed on the tapered cover, and the elastic member is connected between the first limiting member and the second limiting member. Further, the elastic member is, for example, a spring. In an embodiment of the present invention, the linkage device may include an eccentric cam and a handle, wherein the eccentric cam is disposed beside the air inlet surface of the filter, and the handle is connected to the eccentric cam to drive the eccentric cam to push the filter. . In summary, in the air filter system and the filter box of the present invention, since the air guiding unit can guide the exhaust gas directly from the air inlet surface of the filter into the filter, the harmful substances in the exhaust gas are not easily deposited. Filtered online. In addition, when the exhaust fan operates to filter the exhaust gas, the filter tank is in a negative pressure state, so that the exhaust gas can only enter the filter mesh along the air guide unit, so that the exhaust gas leakage can be greatly reduced. The above and other objects, features and advantages of the present invention will become more <RTIgt; Embodiments Fig. 2 is a side view showing a filter box according to an embodiment of the present invention. Referring to Figure 2, the filter box 200 of the present invention is adapted to filter air, particularly to filter exhaust gases associated with production from an experiment or factory. The filter box 200 includes a cover 210, an exhaust vent 220, an inlet 230, a filter 240, a linkage device 250, and a gas guiding unit 260. The air outlet 220 and the air inlet 230 are connected to opposite sides of the outer cover 210, and the filter net 240, the linking device 250 and the air guiding unit 260 are disposed in the outer cover 210, wherein the filter net 240 has an opposite exhaust surface 242 and The wind surface 244, and the linkage device 250 is adapted to abut the exhaust surface 242 of the filter screen 240 against the air outlet 220. Further, the air guiding unit 260 is connected between the air inlet 230 and the air inlet surface 244 of the filter 240. In this embodiment, the filter screen 240 can include a bezel 246 and a filter material 248, wherein the filter material 248 is disposed within the bezel 246 and is adapted to filter exhaust gases. When the exhaust gas enters the filter box 200 from the air inlet 230, the exhaust gas does not spread throughout the outer casing 210, but proceeds in the direction of the air filter unit 260 toward the filter screen 240. When the exhaust gas is filtered by the air inlet surface 244 into the filter 9 1310826 material 248 to form a clean gas, it is then separated from the mesh 240 by the exhaust surface 242.
承接上述，由於導氣單元260連接進風口 23〇與過濾 網240之進風面244,所以廢氣在整個過濾過程中的路徑 P3會被侷限在導氣單元260與過濾網24〇内。此外，導氣 單元260與過遽網240中均沒有不易氣體流動的細缝空 間，所以廢氣可迅速經由過濾網24〇過濾後排放至大氣 中。如此一來’廢氣中的有害物質即不會沉積於過濾網24〇 的外側上，特別疋過濾'網240之邊框246上。故操作人員 在更換過濾網240時，則不需擔心有害物質的影響。 請再參考圖2，在本實施例中’導氣單元26〇可包括 錐形罩體262與彈性伸辭264。錐形軍體脱具有相對 之第—開口 262a與第二開口 262b，而第一開口 262&是靠 合於過濾肩240之進風面244上。詳細而言，第一開口 2仏 ^邊緣是套合於過濾網24G之邊框246側面，而錐形罩體 62是自進風面244向進風口 23〇方向漸縮，亦即錐形罩 休262疋自第-開口 262a往第二開口腿方向漸縮。此 =彈性伸縮管264是連接於錐形罩體加之第二開口腿 口 230之間’而彈性伸缩管264例如為蛇腹管或是 具他合適的遠接#。 值得注意的是，導翁^ χ 白^ 等虱早兀260的設置精神在於將廢氣 自進風口 230處導引至過濾網24〇之進風面施，而本實 也例之錐形罩體262與彈性伸縮管辦的組成乃是搭配進 不二與？風面244大小不同而設計。不過，本發明並 260之組成’熟悉此項技藝者當可參造前 10 1310826 述5兒明對導氣单元260進行適當的改良設計，惟其仍屬於 本發明之範_内。 附帶一提的是’連動裝置250可包括偏心凸輪252與 手把254 ’其中偏心凸輪252是配置於過濾網240之進風 面244旁，而手把254是連接偏心凸輪252。操作人員可 轉動手把254以帶動偏心凸輪252推動過濾網240之邊框 246 ’以使過濾網240之邊框246可緊靠於排風口 220上。 值得強調的是，當過濾箱200在過濾廢氣時，導氣單 兀260與過濾網240是呈負壓狀態，所以廢氣可經由過濾 網240過濾後’迅速從排風口 22〇離開過濾箱2〇〇。因此， 操作人員不需特別對過濾網24〇施加很大的壓力以緊靠於 排風口 220上’則過濾網24〇之邊框246與排風口 220自 然便具有良好的密封裝態。再加上廢氣在過濾的過程中根 本不會充滿於過濾網240與外罩21〇之間的縫隙S中，因 此本發明之過濾箱200可大幅降低漏氣的問題。 清再參考圖2 ’為使導氣單元26〇之錐形罩體262能 進一步緊罪於過濾網240之進氣面244上，過濾箱200更 可包括定位襄置270,其中定位裝置27〇是配置於外罩210 内，並適於使錐形罩體262之第一開口 262a緊靠於過濾網 240之進風面244上，以增加錐形罩體262與過濾網24〇 之邊框246的密封程度。 承接上述，定位裝置270可包括第一限位件272、第 一限位件274以及彈性元件276。第一限位件272是配置 於外罩210上’而第二限位件274是配置於錐形罩體262 上’且彈性元件276是連接於第一限位件272與第二限位In the above, since the air guiding unit 260 is connected to the air inlet 23 〇 and the air inlet surface 244 of the filter 240, the path P3 of the exhaust gas during the entire filtering process is limited to the air guiding unit 260 and the filter net 24 。. Further, neither the air guide unit 260 nor the over-twisting net 240 has a slit space in which gas flow is difficult, so that the exhaust gas can be quickly filtered through the filter 24 and discharged to the atmosphere. In this way, the harmful substances in the exhaust gas are not deposited on the outer side of the filter 24, especially on the frame 246 of the filter 'net 240. Therefore, when the operator replaces the filter 240, there is no need to worry about the influence of harmful substances. Referring again to Fig. 2, in the present embodiment, the air guiding unit 26A may include a tapered cover 262 and an elastic rib 264. The tapered body has a first opening 262a and a second opening 262b, and the first opening 262 & is abutted against the air inlet surface 244 of the filter shoulder 240. In detail, the edge of the first opening 2仏 is sleeved on the side of the frame 246 of the filter 24G, and the tapered cover 62 is tapered from the air inlet surface 244 toward the air inlet 23, that is, the cone cover 262疋 tapers from the first opening 262a toward the second opening leg. This = the elastic bellows 264 is connected between the conical cover and the second open leg 230, and the elastic telescoping tube 264 is, for example, a bellows or a suitable remote. It is worth noting that the spirit of the guide ^ χ white 虱 虱 虱 兀 260 is to guide the exhaust gas from the air inlet 230 to the air inlet surface of the filter 24, and the cone cover of the present example The composition of the 262 and the elastic telescopic tube is matched with it? The wind surface 244 is designed in different sizes. However, the present invention and the composition of 260 are familiar to those skilled in the art and can be suitably modified to design the gas guiding unit 260, but still fall within the scope of the present invention. Incidentally, the ' linkage device 250 can include an eccentric cam 252 and a handle 254' wherein the eccentric cam 252 is disposed adjacent the air inlet surface 244 of the filter screen 240 and the handle 254 is coupled to the eccentric cam 252. The operator can rotate the handle 254 to drive the eccentric cam 252 to push the frame 246' of the filter 240 so that the frame 246 of the filter 240 can abut against the vent 220. It is worth emphasizing that when the filter box 200 is filtering the exhaust gas, the air guide unit 260 and the filter screen 240 are in a negative pressure state, so that the exhaust gas can be filtered through the filter screen 240 and then quickly exit the filter box 2 from the exhaust port 22〇. Hey. Therefore, the operator does not need to apply a large pressure to the filter screen 24 to abut against the air outlet 220. The frame 246 and the air outlet 220 of the filter screen 24 naturally have a good sealed state. Further, the exhaust gas is not filled in the gap S between the filter 240 and the outer cover 21〇 during the filtration process, so that the filter case 200 of the present invention can greatly reduce the problem of air leakage. Referring again to FIG. 2, in order to make the conical cover 262 of the air guiding unit 26 further sin on the air inlet surface 244 of the filter 240, the filter box 200 may further include a positioning device 270, wherein the positioning device 27 It is disposed in the outer cover 210 and is adapted to abut the first opening 262a of the tapered cover 262 against the air inlet surface 244 of the filter net 240 to increase the frame 246 of the tapered cover 262 and the filter screen 24 The degree of sealing. In response to the above, the positioning device 270 can include a first stop member 272, a first stop member 274, and a resilient member 276. The first limiting member 272 is disposed on the outer cover 210 and the second limiting member 274 is disposed on the tapered cover 262. The elastic member 276 is coupled to the first limiting member 272 and the second limiting member.
131〇826 件2 74之間以提供彈力使第一限位件2 72與第二限位件2 7 * 的間距增加。如此一來，第二限位件274即會帶動錐形罩 體262在過遽網240的方向移動，而使第一開口 262a緊靠 於進風面244上。在本實施例中，彈性元件276例如為彈 簧’不過本發明並不限定彈性元件276之種類。 圖3為依據本發明一實施例之空氣過濾系統之側面示 意圖。請參考圖3 ’本發明之空氣過濾系統300包括過遽 相310、抽風機320、第一導風管330與第二導風管340， 其中過濾箱310可為前述實施例之過濾箱2〇〇(如圖2所示） 或是具有本發明特徵之過濾箱。第一導風管330是連接於 抽風機320與過遽箱310之排風口 312之間，而第二導風 管340是連接過遽箱310之進風口 314,且第二導風管340 之另一端是連接至產生廢氣的機器設備（未緣示）。 當抽風機320啟動時’廢氣會由第二導風管“ο進入 過濾箱3!0内進行過濾，再由第一導風管33〇進入抽風機 320後排放於大氣中。由於過滤箱31〇的特殊設計可大幅 降低廢氣外漏關題’因此本發明之空氣過齡統3〇〇具 有較佳的過濾效果。 附帶-提的是，儘管在本實施例中僅以單一過濾箱31〇 為例作說明，但是本發明之空氣職“ 亦可配置多 個串聯之過濾箱310來增進调、、看 “饰τ 過濾效果。熟知此項技藝者當 可輕易推出’於此便不再警·迷。 綜上所述’本發明之空氣仍:索备 礼過/慮糸統與其過濾箱至少具 有下列優點： 藉 由導氣單元^丨廢氣從進風 口進入過濾網之進 12 .1310826 , 風面而進行過濾，可使廢氣中的有害物質不易沉積於過濾 網上，特別是過濾、網之邊框上。如此可使操作人員在更換 ' 過濾網時，不會沾附到邊框上的有害物質，進而避免有害 ' 物質危害健康。 二、在過濾的過程中，導氣單元與過濾網均是呈負壓 狀態，因此廢氣從導氣單元進入過濾網過濾後，便會迅速 從排風口離開過濾箱。如此可大幅降低漏氣的問題，以提 昇過遽效果。 • 雖然本發明已以較佳實施例揭露如上，然其並非用以 限定本發明，任何熟習此技藝者，在不脫離本發明之精神 和範圍内，當可作些許之更動與潤飾，因此本發明之保護 範圍當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】 圖1為習知之一種過滤箱的側面示意圖。 圖1A為圖1之過滤·網的立體不意圖。 # 圖2為依據本發明一實施例之過濾箱的側面示意圖。 圖3為依據本發明一實施例之空氣過濾系統之侧面示 意圖。 【主要元件符號說明】 100 :過濾箱 110 :外罩 120 :排風口 130 :進風口 .1310826 過濾網 排風面 進風面 邊框 過濾、材質 偏心凸輪 手把 310 :過濾、箱 外罩 312 :排風口 314 :進風口 過濾網 排風面 進風面 邊框 過滤材質 連動裝置 偏心凸輪 手把 導氣單元 錐形罩體 :第一開口 :第二開口 彈性伸縮管 定位裝置 .1310826 272 :第一限位件 鬌 274 :第二限位件 ' 276 :彈性元件 300 :空氣過濾系統 320 :抽風機 330 :第一導風管 340 :第二導風管 PI、P2、P3 :路徑 • S :缝隙The distance between the first limiting member 2 72 and the second limiting member 2 7 * is increased between the 131 〇 826 pieces 2 74 to provide the elastic force. In this way, the second limiting member 274 drives the tapered cover 262 to move in the direction of the weft web 240, so that the first opening 262a abuts against the air inlet surface 244. In the present embodiment, the elastic member 276 is, for example, a spring. However, the present invention does not limit the type of the elastic member 276. Figure 3 is a side elevational view of an air filtration system in accordance with an embodiment of the present invention. Referring to FIG. 3, the air filter system 300 of the present invention includes an over-twisted phase 310, an exhaust fan 320, a first air duct 330 and a second air duct 340, wherein the filter box 310 can be the filter box 2 of the foregoing embodiment. 〇 (as shown in Figure 2) or a filter box having the features of the present invention. The first air duct 330 is connected between the exhaust fan 320 and the air outlet 312 of the buffer box 310, and the second air duct 340 is connected to the air inlet 314 of the box 310, and the second air duct 340 The other end is connected to the machine that produces the exhaust gas (not shown). When the exhaust fan 320 is started, the exhaust gas is filtered by the second air duct ο into the filter box 3!0, and then enters the air blower 320 by the first air duct 33, and is discharged into the atmosphere. The special design of the crucible can greatly reduce the exhaust gas leakage problem. Therefore, the air overage system of the present invention has a better filtering effect. Incidentally, although in the present embodiment, only a single filter box 31 is used. For example, the air job of the present invention can also be configured with a plurality of filter boxes 310 connected in series to enhance the adjustment and to see the effect of the decoration τ filtering. Those skilled in the art can easily launch the device. In summary, the air of the present invention is still provided with the following advantages: at least the following advantages are obtained: through the air guiding unit, the exhaust gas enters the filter from the air inlet into the 12.1310826, Filtration on the wind surface makes it difficult for harmful substances in the exhaust gas to deposit on the filter screen, especially on the border of the filter and the net. This allows the operator to change the 'filter' without getting harmful to the frame. Substance, and thus avoid harmful ' The substance is harmful to health. 2. In the process of filtration, both the gas guiding unit and the filter net are in a negative pressure state, so after the exhaust gas enters the filter screen from the gas guiding unit, it will quickly leave the filter box from the exhaust vent. The problem of air leakage is reduced to improve the effect of the smashing. • Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the invention, and it is within the spirit and scope of the present invention. The scope of protection of the present invention is defined by the scope of the appended claims. [Fig. 1 is a schematic side view of a conventional filter box. Figure 1A 3 is a schematic side view of a filter box according to an embodiment of the present invention. Fig. 3 is a side view of an air filter system according to an embodiment of the present invention. Description] 100: filter box 110: outer cover 120: air outlet 130: air inlet. 1310826 filter air outlet surface air inlet frame filter, material eccentric cam handle 310: Filter, box cover 312: exhaust 314: air inlet filter screen exhaust surface inlet surface filter material linkage device eccentric cam handle air guide unit cone cover: first opening: second open elastic telescopic tube positioning device. 1310826 272: first limiting member 鬌 274: second limiting member '276: elastic member 300: air filtering system 320: exhaust fan 330: first air guiding tube 340: second air guiding tube PI, P2, P3: Path • S: gap