200907178 九、發明說明： 【發明所屬之技術領域】 本發明是有關於一種散熱風扇，特別是指—種單定子 外極式散熱風扇。 【先前技術】 目前的家電用品皆以輕薄短小的設計方向為主流，但 是一般電子用品於長時間使用時，往往會產生高熱。為能 即時帶走熱量，同時又符合輕薄短小之要求，因此，外極 式散熱風扇便從中應運而生，形成一種新型態的風扇設計 多閱圖1、2，習知單定子外極式散熱風扇1包含有一 中二狀喊體U、—可轉動地設於該殼體11内之轉子12、一 通電激磁以感應驅動該轉子12旋轉的定子13、—設於該殼 體11内側底面上且與該定子13形成電連接㈣路板14 , =一同樣電連接於該電路板14且面對該轉子12的感應元 该轉子12具有一心軸120、一設於該心軸120上之輕 較121、多數片設於該触⑵外緣之葉片122，及: 於所述葉片122外绫之拔雜尸"，丄 路當料子13藉由該電 路板14通電激磁後200907178 IX. Description of the Invention: [Technical Field] The present invention relates to a heat dissipating fan, and more particularly to a single stator external pole type cooling fan. [Prior Art] Current home appliances are mainly in the light, short and short design direction, but in general, electronic products often generate high heat when used for a long time. In order to take away heat immediately, and at the same time meet the requirements of light and thin, therefore, the external-pole cooling fan will emerge from it, forming a new type of fan design. Read more, Figure 1, 2, the conventional single-stator outer pole The cooling fan 1 includes a middle and a second body U, a rotor 12 rotatably disposed in the casing 11, a stator 13 electrically energized to inductively drive the rotation of the rotor 12, and a bottom surface disposed on the inner side of the casing 11. And electrically connected to the stator 13 (four) way board 14 , a sensor element that is also electrically connected to the circuit board 14 and facing the rotor 12 . The rotor 12 has a mandrel 120 and is disposed on the mandrel 120 . Lighter than 121, a plurality of blades are disposed on the outer edge of the contact (2), and: the outer surface of the blade 122 is smashed, and the rafter 13 is energized by the circuit board 14
便可利用磁性互斥作用驅動該轉子12 之磁鐵環123，進而遠叙^ -得于U 選而連動該轉子12之葉片122旋轉。 該感應元件I 5目I丨-Γ、. I & 拉續、、 在磁鐵環123旋轉的過程中， 持續感應δ亥磁鐵環】）q 叔U Μ…變化’並將訊號送至該電路 扳14，以使該定子η 电崎 13持續通電激磁而將該轉子12以同一 200907178 方向加以推動旋轉。 然而上述設計中，由於該轉子12的磁 於所述葉片122外緣，因此，葉片122_ 3疋環設 大面積時’該磁鐵環123隨之也要擴，二=擴 重量增加，而且整體允φ^^ 不但材料與 體積。 也要向外擴張’無法有效地縮小 參閱圖3，為了解決上述缺點，便將圖2所示的磁 123設置成固設於所述荦片 衣 吓述莱片122底緣，藉此讓葉片122向外 延伸擴大面積，提高散熱效果，此時，該磁•裏123就會 殼體11之内側底面；反觀該定子13與感應元件 μ則會因為設置於該電路板14上，且該電路板14又〜 置於該殼體u之内側底面上，導致該定子13與感應= 15相較於磁鐵環123,於高度方面多出該電路板14的厚度 ’反而造成該感應以牛15不易確實地感應該磁鐵環123 $ 極性變化，該定子13也不易確實地以磁性互斥作用驅動該 磁鐵環123旋轉，連帶使得該轉子12的旋轉作動相當不穩 定。 因此，如何在該磁鐵環123設置為貼近於該殼體u之 内側底面時，同時也可以達成該定子13與感應元件15與 磁鐵環123確實感應的目的，便成為相關業者所亟需努力 研究的目標。 【發明内容】 因此’本發明之目的，即在提供一種旋轉穩定性較佳 的單定子外極式散熱風扇。 200907178 於疋，本發明單定子外極式散熱風扇，包含一基座、 -樞設於該基座的轉子單元、—接設於該基座 内的電路單 兀，及一驅動該轉子單元旋轉的定子單元。 δ亥基座具有一基壁，及一突設於該基壁上的圍壁該 基壁與圍壁相配合界定出一容置空間，且該基壁具有一呈 貝通狀的鏤空部。該轉子單元具有—樞^於該基座之基壁 上的輪轂、多數片間隔環設於該輪轂周緣的葉片，及一設 於所述葉片周緣的感應磁鐵環。該電路單元具有一接設於 該基壁之教部㈣電路板，及―電連·該電路板且面 向該感應磁鐵環以感應其極性的感應元件。該定子單元係 與名電路板形成電連接，並藉由該電路板通電而使該定子 單几產生激磁現象，進而與該轉子單元之感應磁鐵環相互 感應’以推動該感應磁鐵環旋轉。 本發明之功效在於，藉由在該基壁上開設有鏤空部， 以供該電路板接設於其中，使得電連接設置於該電路板上 的定子單7L與感應元件都能隨之降低高度，再搭配該感應 磁鐵環也可以設計為貼近該基壁（即高度較低），因此，該 定子單元與感應元件便能確實與高度較低的感應磁鐵環互 相感應’提高該轉子單元的旋轉穩定性。 【實施方式】 有關本發明之前述及其他技術内容、特點與功效，在 以下配合參考圖式之三個較佳實施例的詳細說明中，將可 清楚的呈現。 在本發明被詳細描述之前，要注意的是，在以下的說 200907178 明中’類似的疋件是以相同的編號來表示。 參閱圖4'5,本發明單定子外極式散熱風扇2的第一 車又佳《 %例，包含一基座21、一樞設於該基座21的轉子單 70 22 接攻於該基座21内的電路單元23,及一驅動該 轉子單元22旋轉的定子單元μ。 °亥基座21具有一基壁211，及一突設於該基壁21ι上 且Η呈u形的圍壁212,該基壁211與圍壁相配合界定 出谷置空間213，且該基壁211具有一呈貫通狀的鎮空部 217 〇 該轉子單元22具有一樞設於該基座21之基壁211上的 輪轂221、多數片間隔環設於該輪轂221周緣的葉片222， 及°又於所述葉片222周緣的感應磁鐵環223。 違輪轂221具有一樞設於該基座21之基壁2ΐι上的中 輪較。Ρ 224、多數條由該中心輪較部224間隔輕射向外延 伸的肋條部225，及-環接於所述肋條部225末端且供該感 應磁鐵環223套設於其外側的圓環部226，每-葉片222具 有同時固δ又於该圓環部226與感應磁鐵環223兩者頂緣 葉Ρ 227、—同時固設於該圓環部226與感應磁鐵環 兩者底緣的底f部228，及-連接該頂、底葉部227、 228且位於該圓環部226内側的中葉部229。 該電路單元23具有-卡制接設於該基壁2ιι之縷空部 =内的電路板231，及-電連接於該電路板231且面向該 感應磁鐵環223以感應其極性的感應元件232。 232與定子單元24 °亥電路板231具有一供該感應元件 200907178 電連接設置的本體233，及設於該本體233周緣且分處相反 兩側的一卡制件234與一插置件235。 當本實施例欲進行組裝時，可以一開始就將該轉子單 元22樞設於該基座21之基壁211上，或是直到組裝過程最 後才將該轉子單元22樞設於該基座21之基壁211上，兩種 方式皆不會影響該電路板231的組裝過程，所以在此就不 詳加贅述該轉子單元22的組裝動作。 參閱圖6,該卡制件234具有一由該本體233周緣伸置 於該容置空間213且可彈性復歸的懸臂部237，及—連接該 懸臂部237且可脫離地觸抵於該鎮空部217周緣的觸抵部 239。該插置件235則可插置於該容置空間213内且與該鎮 空部21 7周緣互相配合嵌接。 以下則詳細說明該電路板231的組裝過程： 一併參閱圖6、7，首先將該電路板231之插置件235 以傾斜方式插置於該容置空Μ 213内，便可利用該鎮空部 217周緣而形成互相配合嵌接，藉此讓該電路板231之一側 先產生卡制限位之效果；然後再將該卡锻234向該鏤空 部爪方向移動（如圖6中箭頭所禾），此時該卡制: =34便會沿著該鏤空部217周緣滑移，而逐漸壓迫變形該懸 是4 237 ’直到該懸臂部237不再被壓迫變形時，就會復歸 呈原本狀’並且該觸抵部239便可以觸抵於該鏤空部爪 周緣，進+而使得該電路231之另外一側也產生卡制限位 之效果，藉此方式，使得該電路板231是卡制接設於 空部217内。 200907178 如圖5所不，經過上述組裘過程之後，當該單定子外 極式散熱風扇2通電運轉時，該定子單元24就可以藉由該 電路板23!通電而使該定子單元24產生激磁現象，進而與 該轉子單元22之感應磁鐵環223相互感應，以推動該感應 磁鐵環223旋轉。 因此，本實施例單定子外極式散熱風扇2於實際使用 上’具有以下所述之優點： (1) 提高該轉子單元22的旋轉穩定性： 本實施例係藉由在該基壁211上開設有鏤空部 2Π，用以供該電路板231接設於其中，使得電連 接設置於該電路板231上的定子單元24與感應元 件32都此卩通之降低南度，再搭配該感應磁鐵環 223是被所述葉片222之頂、底葉部227、夾 設其中而更為貼近該基壁211 (即高度較低），因 此，便能確實與高度較低的感應磁鐵環223互相 感應，提高該轉子單元22的旋轉穩定性。 (2) k咼政熱效果、適用於狹窄的高熱環境： 藉由5亥感應磁鐵環223是被所述葉片222之 頂、底葉部227、228夾設其中，因此，所述葉片 似之頂、底葉部227、228便不會被該感應磁鐵 環223所侷限，而能夠有效地向外橫向延伸擴大 面積、提高散熱效果，並不會連帶使得該感應磁 鐵環223、基座21隨之也要橫向擴大；整體而言 ，該單定子外極式散熱風扇2不僅可以提高散熱 10 200907178 效果，而且該感應磁鐵環223的材料與重量也不 會增加，甚至該基座21也毋需擴大寬度，相當適 用於狹窄的高熱環境。 參閱圖8，本發明單定子外極式散熱風扇2的第二較佳 實施例，大致類似於前述第一較佳實施例，不同的地方在 於.本實施例之電路板231不具有卡制件234與插置件235 的設計，並且本實施例之基座21更具有一由該基壁211伸 置於該容置空間213内的突垣214，及多數個由該突垣214 周緣向該鏤空部217内延伸設置的中空狀突柱216 (圖8因 視角關係只繪出一個），該電路板231之本體233是觸抵於 所述犬柱216上，且該電路板23丨更具有多數個貫通該本 體233且對應所述突柱216的穿孔236，以配合藉由多數個 螺合件25穿伸過穿孔236且螺合固定於突柱216内部，而 將§亥電路板231由下往上接設於該基壁211之鏤空部217内 〇 藉由上述設計，本實施例除了能夠達成第一較佳實施 例所載之功效以外，而且也提供相異於第一較佳實施例之 組裝方式，利用多數個螺合件25將電路板231之本體233 與該基座21之突柱216予以對應螺合固定在一起，形成許 夕的接觸結合點，使得該電路板23丨接設於該基壁2丨丨之鏤 空部217内時，能夠產生更為牢固、不易分離脫落的功效 〇 參閱圖9，本發明單定子外極式散熱風扇2的第三較佳 實施例，大致類似於前述第一較佳實施例，不同的地方在 11 200907178 於.本實施例疋將第一較佳實施例之卡制接設方式與第二 較佳實施例之螺合接設方式，予以組合起來同時使用，因 此本實施例一方面可以利用該卡制件234與插置件235 的认计，而將該電路板231卡制於該基壁211之鏤空部217 内另方面，則可以利用螺合件25與突柱216的設計， 於該電路板231接設於該基壁211之鏤空部217内，產生許 夕们接觸，、Ό σ點，因此，本實施例不僅確實可以達成前述 第一、二較佳f施例所載之功交文’同8寺也可以使得該電路 板231卡制於該鏤空部217内的效果更為優異。 歸納上述，本發明單定子外極式散熱風扇2，藉由在該 基壁211上開設有鏤空部217，藉以供該電路板231接設於 其中，使得電連接設置於該電路板231上的定子單元24與 感應元件232都能隨之降低高度，再搭配該感應磁鐵環出 也可以設計為貼近該基壁211 (即高度較低），因此該定 子單元24與感應元件232便能讀實與高度較低的感應磁鐵 環233互相感應，提高該轉子單元22的旋轉穩定性。 再者，每一葉片222之頂、底葉部227、228也不會被 該感應磁鐵環223所侷限，而能夠有效地向外橫向延伸擴 大面積、提高散熱效果。 ' 此外，也可以利用該卡制件234與插置件235的設計 ，而將該電路板231卡制於該基壁211之鏤空部217内， 或是也可以再搭配利用螺合件25與突柱216的設計，使得 该電路板231接設於該基壁211之鏤空部217内產 多個接觸結合點，進而讓該電路板231更為牢固地接設於 12 200907178 該基壁2U之鏤空部217内，所以確實能夠達到本發明之 目的。 惟以上所述者，僅為本發明之較佳實施例而已，當不 能以此限定本發明實施之，即大凡依本發对請專利 範圍及發明說明内容所作之簡單的等效變化與修飾，皆仍 屬本發明專利涵蓋之範圍内。 【圖式簡單說明】 广是-俯視圖’說明習知之單定子外極式散熱風扇 ，省略繪出其殼體頂面，以便於觀察殼體内部構件； 圖2是一側視剖視圖，輔助說明圖丨所示之單定子外 極式散熱風扇； 圖3是一側視剖視圖，說明另一種習知之單定子外極 式散熱風扇； 圖4是一立體分解圖，說明本發明單定子外極式散熱 風扇之第一較佳實施例；The magnet ring 123 of the rotor 12 can be driven by magnetic mutual repulsion, and the rotor 122 of the rotor 12 can be rotated by the U-selection. The sensing element I 5 mesh I丨-Γ, . I & pull, during the rotation of the magnet ring 123, continuously inductively δ 磁铁 磁铁 】 ) ) ) ) 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化 变化The 14 is pulled so that the stator η 电 13 13 continues to be energized and the rotor 12 is pushed and rotated in the same 200907178 direction. However, in the above design, since the rotor 12 is magnetized to the outer edge of the blade 122, when the blade 122_3 is provided with a large area, the magnet ring 123 is also expanded, and the weight is increased, and the overall weight is increased. Φ^^ Not only material and volume. Also expanding outwardly' cannot be effectively reduced. Referring to FIG. 3, in order to solve the above disadvantages, the magnetic 123 shown in FIG. 2 is disposed to be fixed to the bottom edge of the cymbal cymbal 114, thereby allowing the blade 122 extends outward to enlarge the area to improve the heat dissipation effect. At this time, the magnetic core 123 has an inner bottom surface of the casing 11; in view, the stator 13 and the sensing element μ are disposed on the circuit board 14, and the circuit The plate 14 is placed on the inner bottom surface of the casing u, so that the stator 13 and the induction ring 15 are compared with the magnet ring 123, and the thickness of the circuit board 14 is increased in height. The magnet ring 123 is positively sensed to change polarity, and the stator 13 is also less likely to positively drive the magnet ring 123 to rotate with magnetic mutual repulsion, which in turn makes the rotation of the rotor 12 relatively unstable. Therefore, when the magnet ring 123 is disposed close to the inner bottom surface of the casing u, the purpose of the stator 13 and the sensing element 15 and the magnet ring 123 can be accurately sensed, and it is an urgent need for the related researcher to study hard. The goal. SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a single stator external pole type cooling fan which is excellent in rotational stability. 200907178 于疋, the single stator external pole cooling fan of the present invention comprises a base, a rotor unit pivoted to the base, a circuit unit connected to the base, and a drive unit rotating Stator unit. The δHai base has a base wall and a surrounding wall protruding from the base wall. The base wall cooperates with the surrounding wall to define an accommodating space, and the base wall has a shell-shaped hollow portion. The rotor unit has a hub pivotally mounted to a base wall of the base, a plurality of spaced apart rings disposed on a periphery of the hub, and an inductive magnet ring disposed on a periphery of the blade. The circuit unit has a teaching board (four) circuit board connected to the base wall, and an inductive element that electrically connects the circuit board and faces the induction magnet ring to sense its polarity. The stator unit is electrically connected to the name circuit board, and the stator is energized to cause an excitation phenomenon, and the induction magnet ring of the rotor unit is induced to rotate to drive the induction magnet ring to rotate. The utility model has the advantages that the hollow portion is opened on the base wall for the circuit board to be connected therein, so that the stator single 7L and the sensing element electrically connected to the circuit board can be lowered in height. The induction magnet ring can also be designed to be close to the base wall (ie, the height is low), so that the stator unit and the sensing element can positively interact with the lower height induction magnet ring to improve the rotation of the rotor unit. stability. The above and other technical contents, features and effects of the present invention will be apparent from the following detailed description of the preferred embodiments of the drawings. Before the present invention is described in detail, it is to be noted that in the following description, the similar elements are denoted by the same reference numerals. Referring to FIG. 4'5, the first vehicle of the single-stator external-pole type heat-dissipating fan 2 of the present invention is preferably "% of the case, including a base 21, and a rotor unit 70 22 pivotally mounted on the base 21 is attached to the base. The circuit unit 23 in the seat 21 and a stator unit μ that drives the rotation of the rotor unit 22. The hoist base 21 has a base wall 211, and a surrounding wall 212 protruding from the base wall 21a and having a U-shape. The base wall 211 cooperates with the surrounding wall to define a valley space 213, and the base wall The 211 has a through-hole portion 217. The rotor unit 22 has a hub 221 pivotally mounted on the base wall 211 of the base 21, and a plurality of blades 222 disposed on the periphery of the hub 221, and Further, an induction magnet ring 223 is formed on the periphery of the blade 222. The wheel hub 221 has a middle wheel that is pivotally mounted on the base wall 2'' of the base 21. Ρ 224, a plurality of rib portions 225 extending outward from the center wheel portion 224, and a ring portion circumscribing the end of the rib portion 225 and sleeved on the outer side of the induction magnet ring 223 226, each of the blades 222 has a simultaneous solidification δ and a top edge of the annular portion 226 and the induction magnet ring 223, and is fixed to the bottom of the bottom edge of the annular portion 226 and the induction magnet ring. The f portion 228, and the middle leaf portion 229 that connects the top and bottom leaf portions 227 and 228 and is located inside the annular portion 226. The circuit unit 23 has a circuit board 231 that is connected to the hollow portion of the base wall 2 ι, and an inductive element 232 that is electrically connected to the circuit board 231 and faces the induction magnet ring 223 to sense its polarity. . 232 and the stator unit 24 ° circuit board 231 has a body 233 for electrically connecting the sensing element 200907178, and a card member 234 and an interposing member 235 disposed on the periphery of the body 233 and on opposite sides of the body 233. When the embodiment is to be assembled, the rotor unit 22 can be pivoted on the base wall 211 of the base 21 at the beginning, or the rotor unit 22 can be pivoted to the base 21 until the end of the assembly process. The two methods of the base wall 211 do not affect the assembly process of the circuit board 231. Therefore, the assembly operation of the rotor unit 22 will not be described in detail herein. Referring to FIG. 6 , the clip 234 has a cantilever portion 237 extending from the periphery of the body 233 and resiliently retractable to the receiving space 213 , and connecting the cantilever portion 237 and detachably contacting the air gap. The contact portion 239 around the portion 217. The insertion member 235 is inserted into the accommodating space 213 and is engaged with the peripheral edge of the hollow portion 217. The assembly process of the circuit board 231 will be described in detail below. Referring to Figures 6 and 7, the interposer 235 of the circuit board 231 is first inserted into the accommodating space 213 in an inclined manner to utilize the town. The peripheral portion 217 is formed to be engaged with each other, thereby causing the side of the circuit board 231 to first produce a locking limit effect; and then the forging 234 is moved toward the hollow portion claw (as shown by the arrow in FIG. 6). Wo), at this time the card: =34 will slip along the circumference of the hollow portion 217, and gradually compress the deformation of the suspension is 4 237 ' until the cantilever portion 237 is no longer compressed and deformed, it will return to the original And the contact portion 239 can touch the periphery of the hollow portion claw, and the other side of the circuit 231 also has the effect of locking the limit, thereby making the circuit board 231 a card. Connected to the empty portion 217. 200907178 As shown in FIG. 5, after the above-described grouping process, when the single-stator external-pole cooling fan 2 is energized, the stator unit 24 can be energized by the circuit board 23! The phenomenon is further induced by the induction magnet ring 223 of the rotor unit 22 to urge the induction magnet ring 223 to rotate. Therefore, the single-stator external-pole heat-dissipating fan 2 of the present embodiment has the following advantages in practical use: (1) Improving the rotational stability of the rotor unit 22: This embodiment is performed on the base wall 211. The hollow portion 2 is opened for the circuit board 231 to be connected thereto, so that the stator unit 24 and the sensing element 32 electrically connected to the circuit board 231 are reduced in the south, and the induction magnet is matched. The ring 223 is sandwiched by the top and bottom leaf portions 227 of the blade 222 and is closer to the base wall 211 (i.e., the height is lower), so that it can be positively sensed with the lower height induction magnet ring 223. The rotation stability of the rotor unit 22 is improved. (2) k-thermal thermal effect, suitable for a narrow high-heat environment: by the 5-inch induction magnet ring 223 is sandwiched by the top and bottom blade portions 227, 228 of the blade 222, therefore, the blade is like The top and bottom leaf portions 227 and 228 are not limited by the induction magnet ring 223, and can effectively extend outwardly and laterally to enlarge the area and improve the heat dissipation effect, so that the induction magnet ring 223 and the base 21 are not attached. In general, the single stator external pole cooling fan 2 can not only improve the heat dissipation 10 200907178 effect, but also the material and weight of the induction magnet ring 223 will not increase, even the base 21 is in need Expanded width, quite suitable for narrow high heat environments. Referring to FIG. 8, a second preferred embodiment of the single-stator external-pole heat dissipating fan 2 of the present invention is substantially similar to the foregoing first preferred embodiment. The difference is that the circuit board 231 of the embodiment does not have a clamping member. 234 and the design of the inserting member 235, and the base 21 of the embodiment further has a protrusion 214 extending from the base wall 211 into the accommodating space 213, and a plurality of the ridges 214 are a hollow stud 216 extending in the hollow portion 217 (only one is shown in FIG. 8 due to the viewing angle), the body 233 of the circuit board 231 is in contact with the dog column 216, and the circuit board 23 has A plurality of through holes 236 extending through the body 233 and corresponding to the studs 216 are engaged to extend through the through holes 236 by a plurality of screw members 25 and are screwed and fixed to the inside of the studs 216, thereby The lower portion is connected to the hollow portion 217 of the base wall 211. With the above design, the present embodiment provides a difference from the first preferred embodiment, and also provides a difference from the first preferred embodiment. For example, the main body of the circuit board 231 is 233 by using a plurality of screwing members 25. The protrusions 216 of the base 21 are screwed and fixed together to form a contact joint of the base, so that when the circuit board 23 is connected to the hollow portion 217 of the base wall 2, it can generate more For the purpose of being firm and not easy to separate and fall off, referring to FIG. 9, a third preferred embodiment of the single-stator external-pole cooling fan 2 of the present invention is substantially similar to the first preferred embodiment described above, and the different places are at 11 200907178. In this embodiment, the carding and connecting manner of the first preferred embodiment and the screwing and connecting manner of the second preferred embodiment are combined and used at the same time. Therefore, in this embodiment, the card member 234 can be utilized. With the insertion of the insert 235, the circuit board 231 is clamped into the hollow portion 217 of the base wall 211, and the design of the screw member 25 and the protruding post 216 can be utilized on the circuit board 231. Provided in the hollow portion 217 of the base wall 211, the contact points are generated, and the σ σ point. Therefore, the present embodiment can not only achieve the above-mentioned first and second preferred f examples. 8 Temple can also cause the circuit board 231 to be stuck in the hollow portion 217 The effect is more excellent. In summary, the single-stator external-pole type heat-dissipating fan 2 of the present invention has a hollow portion 217 formed on the base wall 211, so that the circuit board 231 is connected thereto, so that the electrical connection is disposed on the circuit board 231. Both the stator unit 24 and the sensing element 232 can be lowered in height, and the ring of the induction magnet can also be designed to be close to the base wall 211 (ie, the height is low), so that the stator unit 24 and the sensing element 232 can be read. Induction with the lower height induction magnet ring 233 improves the rotational stability of the rotor unit 22. Moreover, the top and bottom leaf portions 227 and 228 of each of the blades 222 are not limited by the induction magnet ring 223, and the expansion area can be effectively extended laterally outward to improve the heat dissipation effect. In addition, the design of the clamping member 234 and the inserting member 235 can be used to clamp the circuit board 231 into the hollow portion 217 of the base wall 211, or can be combined with the screwing member 25 and The protrusion 216 is designed such that the circuit board 231 is connected to the hollow portion 217 of the base wall 211 to produce a plurality of contact joints, thereby allowing the circuit board 231 to be more firmly connected to the base wall 2U. Since the hollow portion 217 is inside, it is indeed possible to achieve the object of the present invention. However, the above is only the preferred embodiment of the present invention, and the present invention is not limited thereto, that is, the simple equivalent change and modification of the patent scope and the description of the invention according to the present invention. All remain within the scope of the invention patent. [Simplified illustration of the drawing] The wide-top view 'illustrates a conventional single-stator external-pole cooling fan, omitting the top surface of the housing to facilitate observation of the internal components of the housing; FIG. 2 is a side cross-sectional view, an auxiliary explanatory view Figure 3 is a side elevational cross-sectional view showing another conventional single-stator external-pole cooling fan; Figure 4 is an exploded perspective view showing the single stator external-pole heat dissipation of the present invention a first preferred embodiment of a fan;
圖5是一組合剖視圖，輔助說明圖4所示之第一較佳 實施例； X 圖6是一卡接狀態圖，說明該第一較佳實施例之電路 J用插置件與鏤空部周緣互相配合嵌接，藉此讓該電路 板之一側產生卡制限位之效果； 圖7疋 ^接狀態圖，說明圖ό所示之電路板利用卡 制件與鏤空部周緣互相配合嵌接，藉此讓該電路板之另— 側也產生卡制限位之效果； 圖8疋立體分解圖，說明本發明單定子外極式散熱 13 200907178 風扇之第二較佳實施例；及 圖9是一立體圖，說明本發明單定子外極式散熱風扇 之第三較佳實施例。 14 200907178 【主要元件符號說明】 2 單定子外極式散 226 圓環部 熱風扇 227 頂葉部 21 基座 228 底葉部 211 基壁 229 中葉部 212 圍壁 23 電路單元 213 容置空間 231 電路板 214 突垣 232 感應元件 216 突柱 233 本體 217 鏤空部 234 卡制件 22 轉子單元 235 插置件 221 輪轂 236 穿孔 222 葉片 237 懸臂部 223 感應磁鐵環 239 觸抵部 224 中心輪轂部 24 定子單元 225 肋條部 25 螺合件 15FIG. 5 is a cross-sectional view of the first preferred embodiment shown in FIG. 4; FIG. 6 is a card state diagram illustrating the peripheral portion of the circuit J for inserting and hollowing out the first preferred embodiment. Interlocking with each other, thereby causing the effect of the card limit on one side of the circuit board; FIG. 7 is a state diagram showing that the circuit board shown in FIG. 利用 is engaged with the peripheral edge of the hollow portion by the card member, Thereby, the effect of the card limit is also generated on the other side of the circuit board; FIG. 8 is an exploded perspective view showing the second preferred embodiment of the single stator external heat dissipation 13 200907178 fan of the present invention; and FIG. 9 is a A perspective view of a third preferred embodiment of the single stator external pole cooling fan of the present invention. 14 200907178 [Description of main components] 2 single stator external pole 226 annular hot fan 227 top blade 21 base 228 bottom leaf 211 base wall 229 middle part 212 surrounding wall 23 circuit unit 213 accommodation space 231 circuit Plate 214 Projection 232 Inductive element 216 Projection post 233 Body 217 Hollow portion 234 Card member 22 Rotor unit 235 Insert 221 Hub 236 Perforation 222 Blade 237 Cantilever portion 223 Induction magnet ring 239 Contact portion 224 Center hub portion 24 Stator unit 225 rib portion 25 screw member 15