九、發明說明： 【發明所屬之技術領域】 特別係指一種低噪音的離 本發明涉及一種離心風扇 心風扇。 【先前技術】 當前’隨著電腦產業的迅速私 、史發展’微處理晶片等發埶IX. Description of the invention: [Technical field to which the invention pertains] In particular, it relates to a low noise. The present invention relates to a centrifugal fan heart fan. [Prior Art] Current [with the rapid development of the computer industry, history development] micro-processing wafers, etc.
電子疋件產生的熱量愈來愈多。A 夕為將該等多餘的熱量有效 政發’ S知的方法係在發敎雷名- …冤子兀件的表面貼設一散埶 器’然後在該散熱器上設置一湿戶 , 風扇，利用該風扇產生的冷 卻氣流對該散熱器進行強制耑鼽 放利政熱，從而將發熱電子元件產 生的熱量散去。 如圖7所示，-離心風扇9()包括一扇框％及收容於 該扇框95中的葉輪92，該扇框95包括一側壁95〇、一蓋 .板951及一底板953，該等側壁95〇、蓋板951及底板953 圍繞在葉輪92四周，葉輪92產生的高絲流誠在葉輪 92與扇框95間的間隙94中並撞擊側壁95〇，一部分氣流 反彈，入葉輪92(如箭頭所示）内，該反彈氣流與葉輪以產 生的咼壓氣流混合後產生混流從而引起噪音。 【發明内容】 有鑒於此，有必要提供一種能夠降低因混流引發噪音 的離心風扇。 種離心風扇，包括一扇框及一收容於該扇框中的葉 輪，該扇框包括一蓋板及一底板，所述蓋板及底板分別與 底Γ相對，該葉輪包括複數扇葉，該扇框内 面朝有間隙，該底板與蓋板其中之一的内表 圍以阻止間隙中的”:起，該第一凸起圍繞在扇葉周 J丨承甲的軋流回流入扇葉中。 底板：種:：風扇，包括-扇框及-葉輪，該扇框包括-板= 葉輪的外周設置複數扇葉，該扇框的底 隙，該葉輪上還連接有…二:，間均形成有空 並位於扇葉的上貼没在扇葉的末端 流】】葉:起，該凸起阻止扇框内的氣流沿著所述空隙回 致流卜圍組成播板以阻播反彈氣流使其* 頌某甲產生混流，從而降低噪音。 【實施方式】 100,2閱圖1至圖3，為本發明第一實施例的一離心風扇 °"“風扇1GG可與—散熱裝置（@未示）組合用於對發 ;、电子兀件散熱，如中央處理器，該離心風扇⑽包括-扇 框50及一收容於該扇框5〇中的葉輪2〇。 該扇框5〇包括一半封閉的殼體51和-固定在該殼體51 =部的蓋板59。該殼體51包括一底板52和一自該底板训 邊向上延伸而成的側壁53’該底板52中間開設有二弧形孔 54。-圓形底座56設于二弧形孔54之間，該底座^被二弧 形孔54環繞並藉由二臂部如與底板52相連，—管體柳自 該底座56中間向上延伸而成。一半封閉的第一凸起％凸嗖 1333527 於底板52的頂面526，該第一凸起58環繞在二弧形孔54周圍 並用以圍繞所述葉輪20。該底板52具有一弧形邊521及二豎 直邊523、524，所述側壁53自弧形邊521往豎直邊523處延 伸。該第一凸起58與側壁53相對，該第一凸起58靠近豎直 邊524的一側設有開口，該第一凸起58的寬度大致為 0.4mm。所述側壁53二相對側靠近頂部的位置開設有二凹口 532 ;所述蓋板59的輪廓與側壁53的頂部相似並在蓋板59中 央開設有一中心孔590，二扣接部592自蓋板59二相對邊緣 鲁向下延伸而成，該二扣接部592與凹口 532對應並用於將該 蓋板59固定在側壁53頂部。該殼體51、蓋板59共同圍繞形 ' 成一半封閉氣室40用以收容所述葉輪20，該氣室40藉由毗 鄰豎直邊524的一開口（圖未標）與外界相通。 該葉輪20包括一輪轂21及該輪轂21外圍的複數扇葉 25。所述扇葉25包括三第一葉片251及複數第二葉片252， 該等第一葉片251自該輪轂21外圍延伸而成且沿圓周均勻 鲁分佈，該等第二葉片252分別分佈於相鄰的二第一葉片251 之間。一環形圓盤23環繞在該輪轂21周圍並貼設在第一葉 片251及第二葉片252的外圍頂部，一環形第二凸起22自圓 盤23内側向上延伸而出，該第二凸起22的寬度大致為 0.3mm。每一扇葉25的延伸末端沿豎直方向上設有一第三凸 起255，為減少扇葉25中高壓氣流向外流出，該等第三凸起 255自扇葉25末端的一側表面沿與扇葉25旋轉的相反方向 (本實施例為順時針）凸出延伸大致〇.6mm至0.8mm，該等第 三凸起255在扇葉25圓周外圍形成了複數非連續的擋板；該 1333527 等第三凸起255也可設置在扇葉25側面其他位置，然而設置 在末端擋風效果較好。該輪轂21包含一芯軸（圖未標），一軸 承（圖未標）收容于所述管體560中，該葉輪20藉由芯轴裝配 在軸承中從而可旋轉地安裝於殼體51上。 請同時參閱圖4，組裝時，第一凸起58鄰近扇葉25外圍 且其頂面與扇葉25的底面平齊，一方面不會影響扇葉25中 的氣流向外排出，另一方面可阻止反彈氣流沿底板52與扇 葉25間的間隙回流至扇葉25中；扇葉25的外圍末端與該第 ® 一凸起58的内側面之間間隙的寬度大致為0.3mm;所述第二 凸起22的頂面與蓋板59的頂面平齊，該第二凸起22的外圍 ' 面與該蓋板59的内側面之間間隙的寬度大致為0.4mm;該蓋 • 板59底面與圓盤23頂面間的距離大致為0.6mm至0.7mm。在 葉輪20、殼體51及蓋板59之間形成的間隙41中，所述第一 凸起58、第二凸起22及第三凸起255共同組成複數擋板，當 — 葉輪20旋轉時，扇葉25產生的高壓氣流與該殼體51的側壁 鲁53碰撞後反彈，並藉由間隙41朝扇葉25方向流動，所述擋 板可阻擋反彈氣流使其不致流入扇葉25中產生混流，從而 降低噪音。 圖5所示為本發明第二實施例的離心風扇200，該離心 風扇200具有與離心風扇100相似的形狀結構，不同之處在 於：一環形凸起58a形成于蓋板59a與葉輪20a之間以取代第 一實施例中第二凸起22，該凸起58a自該蓋板59a底面向下 延伸並與第一凸起58相對用以阻攔高壓氣流通過該蓋板 59a與葉輪20a之間的間隙。如此，該離心風扇200可省去圓 1333527 盤23結構從而減輕離心風扇2〇〇的重量。 圖6所示為本發明第三實施例的離心風扇_，該離心 風扇300具有與第二實施例中離心風扇2〇〇相似的形狀结 構，不同之_處在於：—圓盤23貼設在葉輪20b的底部，該圓 盤23的第二凸起22向下延伸阻設於圓盤23與底板$沘之 間，以取代第-凸起58的作用，從而該底板可省去第一 • 综上所述，本發明符合發明專利要件，爰依法提屮直 利申請。惟’以上該者僅為本發明之較佳實施例，舉凡孰 μ本#技#之人士’在爰依本發明精神所作之等效修 變化，皆應涵蓋於以下之申請專利範圍内。 ^ 【圖式簡單說明】 圖1係本發明第一實施例離心風扇之立體組合圖。 圖2係圖1中離心風扇之立體分解圖。 鲁圖3係圖1中離心風扇殼體之立體放大圖。 圖4係圖1中離心風扇沿！y-w線之剖視圖。 圖5係本發明第二實施例離心風扇之剖視圖。 圖6係本發明第三實施例離心風扇之剖視圖。 圖7係習知技術中一離心風扇之剖視圖。 【主要元件符號說明】 [習知] 離心風扇 90 葉輪 95 間隙 94 扇框 1333527 側壁 950 盖板 951 底板 953 [本發明]Electronic components generate more and more heat. A eve for the extra heat to validate the 'sense method' in the hairpin name - ... the surface of the 冤 兀 贴 埶 埶 ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' The heat sink generated by the fan is used to force the heat sink to dissipate the heat generated by the heat generating electronic component. As shown in FIG. 7 , the centrifugal fan 9 ( ) includes a frame frame % and an impeller 92 received in the fan frame 95 . The fan frame 95 includes a side wall 95 , a cover plate 951 and a bottom plate 953 . The side wall 95〇, the cover plate 951 and the bottom plate 953 surround the impeller 92. The high wire flow generated by the impeller 92 is in the gap 94 between the impeller 92 and the fan frame 95 and hits the side wall 95〇, and a part of the air flow rebounds into the impeller 92 ( As indicated by the arrow, the bounce gas stream is mixed with the impeller to generate a mixed flow resulting in a mixed flow to cause noise. SUMMARY OF THE INVENTION In view of the above, it is necessary to provide a centrifugal fan capable of reducing noise caused by mixed flow. The centrifugal fan includes a frame and an impeller housed in the frame, the frame includes a cover plate and a bottom plate, and the cover plate and the bottom plate respectively face the bottom cymbal, the impeller includes a plurality of blades, The inner side of the fan frame faces a gap, and the inner surface of one of the bottom plate and the cover plate blocks the gap in the gap: the first protrusion surrounds the rolling flow of the armor of the fan blade and flows back into the fan blade Bottom plate: Kind:: Fan, including - fan frame and - impeller, the fan frame includes - plate = the outer periphery of the impeller is provided with a plurality of blades, the bottom gap of the fan frame, the impeller is also connected with ... Both are formed in the air and are located on the end of the fan blade and are not at the end of the fan blade.] Leaf: The protrusion prevents the airflow in the fan frame from flowing back along the gap to form a broadcast board to block the rebound. The airflow causes the noise to be mixed, thereby reducing the noise. [Embodiment] 100, 2, FIG. 1 to FIG. 3, a centrifugal fan according to a first embodiment of the present invention, "fan 1GG and heat sink" (@not shown) combination for the hair; electronic components, such as the central processing unit, the centrifugal fan (10) includes - The fan frame 50 and an impeller 2 收容 housed in the fan frame 5〇. The frame 5 includes a half-closed housing 51 and a cover 59 fixed to the housing 51. The housing 51 includes a bottom plate 52 and a side wall 53' extending upward from the bottom plate. The bottom plate 52 defines a second arcuate hole 54 therebetween. The circular base 56 is disposed between the two arcuate holes 54. The base is surrounded by the two arcuate holes 54 and connected to the bottom plate 52 by the two arms, and the tubular body extends upward from the middle of the base 56. . A half-closed first raised % tenon 1333527 is on the top surface 526 of the bottom plate 52 that surrounds the two curved holes 54 and surrounds the impeller 20. The bottom plate 52 has an arcuate edge 521 and two vertical sides 523, 524 extending from the curved edge 521 to the vertical side 523. The first protrusion 58 is opposite to the side wall 53. The first protrusion 58 is provided with an opening near one side of the vertical side 524. The first protrusion 58 has a width of approximately 0.4 mm. Two recesses 532 are defined in the opposite sides of the side wall 53 from the top; the cover 59 has a contour similar to the top of the side wall 53 and defines a central hole 590 in the center of the cover 59. The two fastening portions 592 are self-closing. The opposite edge of the plate 59 extends downwardly. The two fastening portions 592 correspond to the notches 532 and are used to fix the cover plate 59 on the top of the side wall 53. The housing 51 and the cover plate 59 together form a half-closed air chamber 40 for receiving the impeller 20, and the air chamber 40 communicates with the outside by an opening (not shown) adjacent to the vertical side 524. The impeller 20 includes a hub 21 and a plurality of blades 25 on the periphery of the hub 21. The fan blade 25 includes three first blades 251 and a plurality of second blades 252. The first blades 251 extend from the periphery of the hub 21 and are evenly distributed along the circumference. The second blades 252 are respectively disposed adjacent to each other. Between the two first blades 251. An annular disk 23 surrounds the hub 21 and is attached to the outer periphery of the first blade 251 and the second blade 252. An annular second protrusion 22 extends upward from the inner side of the disk 23, and the second protrusion The width of 22 is approximately 0.3 mm. The extending end of each of the blades 25 is provided with a third protrusion 255 in the vertical direction. To reduce the outward flow of the high-pressure airflow in the blade 25, the third protrusion 255 is along the side surface of the end of the blade 25. In a direction opposite to the rotation of the blade 25 (clockwise in this embodiment), the protrusion extends approximately 〇6 mm to 0.8 mm, and the third protrusion 255 forms a plurality of non-continuous baffles on the periphery of the blade 25; The third protrusion 255 such as 1333527 can also be disposed at other positions on the side of the blade 25, but the wind shielding effect at the end is better. The hub 21 includes a mandrel (not shown), and a bearing (not labeled) is received in the tube body 560. The impeller 20 is rotatably mounted on the housing 51 by being assembled in a bearing by a mandrel. . Referring to FIG. 4 at the same time, when assembled, the first protrusion 58 is adjacent to the periphery of the blade 25 and its top surface is flush with the bottom surface of the blade 25, on the one hand, does not affect the airflow in the blade 25, and on the other hand, The rebound airflow can be prevented from flowing back into the blade 25 along the gap between the bottom plate 52 and the blade 25; the width of the gap between the peripheral end of the blade 25 and the inner side of the first protrusion 58 is approximately 0.3 mm; The top surface of the second protrusion 22 is flush with the top surface of the cover plate 59, and the gap between the peripheral surface of the second protrusion 22 and the inner side surface of the cover plate 59 is substantially 0.4 mm; the cover plate The distance between the bottom surface of 59 and the top surface of the disk 23 is approximately 0.6 mm to 0.7 mm. In the gap 41 formed between the impeller 20, the housing 51 and the cover plate 59, the first protrusion 58, the second protrusion 22 and the third protrusion 255 together constitute a plurality of baffles, when the impeller 20 rotates The high-pressure airflow generated by the blade 25 rebounds after colliding with the side wall Lu 53 of the casing 51, and flows toward the blade 25 through the gap 41, and the baffle blocks the rebound airflow from flowing into the fan blade 25. Mixed flow to reduce noise. Fig. 5 shows a centrifugal fan 200 according to a second embodiment of the present invention. The centrifugal fan 200 has a similar structure to that of the centrifugal fan 100, except that an annular projection 58a is formed between the cover plate 59a and the impeller 20a. In place of the second protrusion 22 in the first embodiment, the protrusion 58a extends downward from the bottom surface of the cover plate 59a and is opposite to the first protrusion 58 for blocking high pressure airflow between the cover plate 59a and the impeller 20a. gap. Thus, the centrifugal fan 200 can eliminate the structure of the circular 1333527 disk 23 to reduce the weight of the centrifugal fan 2〇〇. Fig. 6 shows a centrifugal fan _ according to a third embodiment of the present invention, which has a shape structure similar to that of the centrifugal fan 2 第二 in the second embodiment, except that the disc 23 is attached to At the bottom of the impeller 20b, the second protrusion 22 of the disc 23 extends downwardly between the disc 23 and the bottom plate 沘 to replace the action of the first protrusion 58 so that the bottom plate can be omitted. In summary, the present invention complies with the requirements of the invention patent, and is suitable for straightforward application according to law. However, the above is only a preferred embodiment of the present invention, and the equivalent modifications made by the person of the present invention in the spirit of the present invention are intended to be included in the following claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective assembled view of a centrifugal fan according to a first embodiment of the present invention. 2 is an exploded perspective view of the centrifugal fan of FIG. 1. Lutu 3 is a perspective enlarged view of the centrifugal fan housing of Fig. 1. Figure 4 is the centrifugal fan along the Figure 1! A cross-sectional view of the y-w line. Figure 5 is a cross-sectional view showing a centrifugal fan according to a second embodiment of the present invention. Figure 6 is a cross-sectional view showing a centrifugal fan according to a third embodiment of the present invention. Figure 7 is a cross-sectional view of a centrifugal fan in the prior art. [Main component symbol description] [Practical] Centrifugal fan 90 Impeller 95 Clearance 94 Fan frame 1333527 Side wall 950 Cover plate 951 Base plate 953 [Invention]
離心風扇 100,200,300 葉輪 20,20a,20b 輪穀 21 第二凸起 22 圓盤 23 扇葉 25 第一葉片 251 第二葉片 252 第三凸起 255 氣室 40 間隙 41 扇框 50 殼體 51 底板 52,52b 弧形邊 521 豎直邊 523,524 頂面 526 側璧 53 凹口 532 弧形子L 54 底座 56 管體 560 臂部 562 第一凸起 58 凸起 58a 蓋板 59,59a 中心孔 590 扣接部 592 11Centrifugal fan 100, 200, 300 Impeller 20, 20a, 20b Valley 21 Second projection 22 Disc 23 Blade 25 First blade 251 Second blade 252 Third projection 255 Air chamber 40 Clearance 41 Fan frame 50 Housing 51 Base plate 52, 52b Curved edge 521 Vertical side 523, 524 Top surface 526 Side 璧 53 Notch 532 Curved sub-L 54 Base 56 Body 560 Arm 562 First projection 58 Projection 58a Cover 59, 59a Center hole 590 Fastener 592 11