TWI329709B

TWI329709B - Centrifugal pump

Info

Publication number: TWI329709B
Application number: TW096146728A
Authority: TW
Inventors: Tetsuya Fukuda; Motohiko Matsuguma
Original assignee: Panasonic Elec Works Co Ltd
Priority date: 2006-12-07
Filing date: 2007-12-07
Publication date: 2010-09-01
Also published as: KR101115362B1; JP4883093B2; JPWO2008069124A1; KR20090078843A; WO2008069124A1; TW200839104A

Description

13297.09 九、發明說明：【發明所屬之技術領域】本發明係有關於一種離心泵者。【先前技術】如第八圖所示般，曰本公開專利第2〇〇6_2〇〇4 2 7唬公報揭示有離心泵。此離心泵係具有定子塊丄，而定子塊1係由：鐵芯及線圈所成的定子2、控制電路3、及隔間板4以嵌件成型的模樹脂所構成。隔間板4位於定子2的内周側，又在其中央部具有凹部4 〇，軸$的一端被凹部4 0所支撐。軸5的外周裝配有轉子6。轉子6係内周部之轴承6 〇及外周側之永久磁鐵6 1形成為一體，同時在軸向的一端側與葉輪7形成一體。此離心泵更具備有機殼8。機殼8係藉由小螺釘而被，定於定子塊1，且在機殼8與隔間板4之間形成有收容葉輪7的泵室。機殼8，係外周側具有吐出口 8丄、中央具備有吸入口 8 〇。又，機殼8係具備用來支撐軸5的另一端之轴支撐部1 〇〇 ’軸支撐部1 0 0，係被從吸入口 8 0周圍之機殼8朝向機殼8内部延伸設置的支撐肋1 〇 1所支撐。在軸支撐部1〇〇之吸入口 8 〇側的面，形成有圓錐體狀之突出部1 〇〇 a，用以將水流導引於葉輪7 側。在此離心泵中，因為是將用以支撐軸5的另一端的軸支撐部1 0 0 —體形成於機殼8，所以具有僅需運用少量零件即可解決問題優點。然而，在軸支撐部丄〇〇的外周 5 13.29709 面與葉輪7的内周面之間具有大的間隙，而造成所謂的空氣在此部分積存而難以排出的問題。【發明内容】本發明乃有鑒於上述問題點而完成者，其目的在於提供一種空氣難以積存在機殼内，且能有效率地排出混雜有氣泡之液體的離心泵。本發明之離心泵係具備：機殼，具有吸入D ;軸支撐部，固定在前述機殼内側；軸，被前述軸支撐部所支撐；13297.09 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a centrifugal pump. [Prior Art] As shown in the eighth drawing, a centrifugal pump is disclosed in Japanese Laid-Open Patent Publication No. 2-6-2〇〇4 2 7唬. The centrifugal pump has a stator block, and the stator block 1 is composed of a stator 2 composed of an iron core and a coil, a control circuit 3, and a partition plate 4 which are formed of insert molding resin. The partition plate 4 is located on the inner peripheral side of the stator 2, and has a recessed portion 4 中央 at its central portion, and one end of the shaft $ is supported by the recessed portion 40. The outer periphery of the shaft 5 is fitted with a rotor 6. The bearing 6 〇 on the inner peripheral portion of the rotor 6 and the permanent magnet 6 1 on the outer peripheral side are integrally formed, and are integrally formed with the impeller 7 at one end side in the axial direction. This centrifugal pump is further provided with an organic casing 8. The casing 8 is fixed to the stator block 1 by means of a small screw, and a pump chamber for accommodating the impeller 7 is formed between the casing 8 and the partition plate 4. The casing 8 has a discharge port 8 外 on the outer peripheral side and a suction port 8 中央 in the center. Further, the casing 8 is provided with a shaft support portion 1 〇〇' shaft support portion 100 for supporting the other end of the shaft 5, and is extended from the casing 8 around the suction port 80 toward the inside of the casing 8. The support rib 1 is supported by 〇1. On the side of the side of the suction port 8 of the shaft support portion 1 is formed a conical projection 1 〇 a for guiding the water flow to the impeller 7 side. In this centrifugal pump, since the shaft support portion 100 for supporting the other end of the shaft 5 is formed in the casing 8, there is an advantage that only a small number of parts can be used to solve the problem. However, there is a large gap between the outer peripheral surface 5 13.29709 of the shaft support portion 与 and the inner peripheral surface of the impeller 7, which causes a problem that so-called air accumulates in this portion and is difficult to discharge. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide a centrifugal pump which is difficult to accumulate air in a casing and can efficiently discharge a liquid in which bubbles are mixed. The centrifugal pump of the present invention comprises: a casing having a suction D; a shaft support portion fixed to the inside of the casing; and a shaft supported by the shaft support portion;

葉輪，被支撐成可於前述軸上旋轉自如，且具有自其内周面朝外周面貫穿的流路，將從前述吸入口流入前述機殼内的液體藉由前述流路排出外部；及驅動部，用以使前述葉輪旋轉。本發明特徵點為，前述軸支撐部具有：形成在前述吸入口侧的面且朝向前述吸入口突出的圓錐體狀之突出部；及設在前述突出部的底部之周圍的周緣部，且前述周緣部之前述吸入口側的面，係從前述突出部之底部朝向前The impeller is supported to be rotatable on the shaft, and has a flow path penetrating from the inner peripheral surface toward the outer peripheral surface, and the liquid flowing into the casing from the suction port is discharged to the outside through the flow path; and driving a portion for rotating the impeller. According to a feature of the present invention, the shaft support portion includes a conical protruding portion that is formed on the surface of the suction port and protrudes toward the suction port, and a peripheral portion that is provided around the bottom of the protruding portion, and the aforementioned The surface of the peripheral portion on the side of the suction port is directed from the bottom of the protruding portion toward the front

述流路的内周面側之開口延伸，且外徑比前述吸入口之内徑還大。本發明之離心泵，係能利用周緣部來填補以往存在於軸支撐部的外面與葉輪的内周面之間的間隙，使得空氣難以積存於機殼内。而且’從吸入口朝向葉輪的流路之^體、，係藉由圓錐體狀之突出部與周緣部之吸人^觸面而被導引至動葉的輪流路之入口（流路的内周面側之開口）附近，其結果，能有效率地排出混雜有氣泡之液體。 ^為，前述軸切部，係由：與前述機殼形成一體前述體狀之突出部的軸支撐部本體、及裝配在支標部本體之外周用以構成前述周緣部的環所構 6 13297,09 成。在此情況’藉由將環裝配於軸支撐部本體之外周容易地形成前述周緣部。The opening on the inner peripheral surface side of the flow path extends, and the outer diameter is larger than the inner diameter of the suction port. In the centrifugal pump of the present invention, the peripheral portion can be used to fill the gap existing between the outer surface of the shaft support portion and the inner peripheral surface of the impeller, so that air is hardly accumulated in the casing. Further, the body of the flow path from the suction port toward the impeller is guided to the inlet of the rotor flow path by the suction portion of the conical portion and the suction portion of the peripheral portion (inside the flow path) In the vicinity of the opening on the circumferential surface side, as a result, the liquid mixed with the bubbles can be efficiently discharged. The axial cut portion is formed by a shaft support portion integrally forming the protruding portion of the body with the casing, and a ring structure configured to surround the outer periphery of the support portion body to form the peripheral portion 6 13297 , 09 成. In this case, the aforementioned peripheral portion is easily formed by fitting the ring to the outer periphery of the shaft support portion body.

或者亦可為’前述軸支樓部係與前述機殼各別形成，且^别述機殼之内面被固定於前述吸入口之端部周緣。如同在欲將機殼及軸支撐部本體形成一體時，在成型機殼時之起模方便上，係難以將吸入口之口徑（内徑）作成^軸支撐部本體之外徑還小。於是，藉由將軸支撐部與機或:各別形成’可無關乎軸支撐部的大小而將吸入口之口徑自由地設小。藉此可提供例如仍舊保持軸支撐部之強度下將吸入口之口徑設小之對應於低流量的離心泵。軚佳為，前述周緣部之前述吸入口側的面，係位於前述葉輪的流路朝向葉輪中心側延長的領域内。此時’就算因為軸承之磨耗等因素使葉輪的位置偏移於機殼側時，亦能順暢地將來自吸入口的水流導引到葉輪之流入口。Alternatively, the shaft support portion may be formed separately from the casing, and the inner surface of the casing may be fixed to the peripheral edge of the suction port. For example, when the casing and the shaft support body are integrally formed, it is difficult to mold the casing at the time of molding, and it is difficult to make the diameter (inner diameter) of the suction port as the outer diameter of the main body of the shaft support. Thus, the diameter of the suction port can be freely set by independently arranging the shaft support portion and the machine to be independent of the size of the shaft support portion. Thereby, it is possible to provide, for example, a centrifugal pump which has a small diameter corresponding to a low flow rate while maintaining the strength of the shaft support portion. Preferably, the surface of the peripheral portion on the suction port side is located in a region in which the flow path of the impeller extends toward the center of the impeller. At this time, even if the position of the impeller is shifted to the casing side due to factors such as wear of the bearing, the flow of water from the suction port can be smoothly guided to the inlet of the impeller.

車父佳為，在前述圓錐體狀之突出部的外面形成有螺狀之階段部。 ' 此時，可賦予從吸入口流入的水旋轉，能更有效率地排出液體。【實施方式】以下，茲一邊參照所附圖式一邊詳細說明本發明。 (第一實施形態）本實施形態之離心泵的基本構造係與第八圖所示之習知例相同，乃如第一圖所示，具備有：定子塊丄；機殼8， 7 13,29709 具有吸入口 8 0 ;軸支撐部8 4，固定在機殼8内側；軸 5，其一端被軸支撐部84支撐而另一端被定子塊1之凹部4 0所支撐；及葉輪7，被支撐成可藉轉子6而在軸5 上旋轉自如。定子塊1，係由：鐵心及線圈所成的定子2、控制電路3、及隔間板4以嵌件成型的模樹脂所構成。定子2、控制電路3，係構成用以旋轉葉輪7之驅動部，隔間板4 係位於定子2之内周側，其底面之中央部形成有凹部4 0 用以支撐前述軸5的另一端，軸5的外周裝配有轉子6。轉子6係一體形成内周部之軸承6 0及外周側之永久磁鐵 6 1，同時在軸向之機殼8側一體形成有葉輪7。機殼8，係藉由固定小螺絲而被固定於定子塊1，在機殼8與隔間板4之間形成有收容葉輪7的栗室。機殼8 的外周側具備吐出口 8 1 (參照第二A圖），中央具備有吸入口 8 0。軸支撐部8 4，係配置於在泵室之内部而與吸入口 8 0相對的位置。針對軸支撐部8 4之構成，詳如後述。葉輪7係由驅動部所驅動且連同轉子6 —起在轴5之周圍旋轉。葉輪7具備有從其内周面朝外周面貫穿的流路 7 0，用以使自吸入口 8 0流入機殼内的水經由流路7 0 而從吐出口 81排出到外部。以下，茲針對軸支撐部8 4作詳細說明。本實施形態之軸支撐部84如第二A、2B圖所示，係由轴支撐部本體8 4 0、及裝配在軸支撐部8 4 0外周的環8 41所構成。 8 13.29709 軸支撐部本體8 4 0，係透過從吸入口8〇之端部周緣的機殼8朝向機殼8内部延伸設置的複數根（圖示例中係3根）支撐肋8 3，而與機殼8形成一體。軸支撐部本體8 4 0，在吸入口 8 〇側之該面，具有朝吸入口8 〇突出的圓錐體狀的突出部8 4 0 a，而在與吸入口 8 〇相反側之面，具有用來支撐軸5的一端之軸承部8 5 〇。 % 8 41係擴張轴支撑部本體8 4 0之外徑，用以構成在突出部8 4 0 a底部之周圍擴展的周緣部者。環8 4 • 1具有與支撐肋8 3對應的複數槽8 4 2，且以支撐肋8 3可嵌合於槽8 4 2之中般地裝配在軸支撐部本體8 4 〇的周圍。環8 41係藉由支撐肋8 3及槽8 4 2之卡合而防止旋轉，又，藉由設在軸支撐部本體8 4 〇端部的階段部8 5與設在環8 41底面的階段部之卡合（未圖示）而執行軸向定位。環8 41係例如依超音波熔接方式而被固疋於轴支樓部本體8 4 〇的周圍。虽環8 41被裝配在轴支撐部本體8 4 〇的周圍後， • 環841之吸入口側的一面841 a，係從突出部84〇 a之底部朝向葉輪7的流路7 〇之内周面側的開口 7丄平緩地延伸，而該面8 4 1 a之外徑（亦即環8 4 1之外徑） k大於吸人口80之内控。環841之外周面係隔著微小間隙與葉輪7的内周面呈相對。本實施形態的離心泵，因為是在軸支撐部本體8 4 〇的周圍裝配有環841，所以能以環841來填補軸支撐部本體8 4 0的外面與葉輪7的内周面之間的間隙，使空氣變得難以積存在機殼内。而且，從吸入口 8 〇朝向葉輪之流路7 0的水’係藉由圓錐體狀之突出部8 4 〇 a及環 9 的開σ = 人口側的面8 4 1 3而順暢地引導至流路7 Ο 液體。附近，其結果，能有效率地排出混雜有氣泡之模方# μ奴將機殼8及軸支撐部8 4形成—體時，在起 0之難以，支樓部8 4之外經作成比吸入口 8 轴支撐(換言之’難以將吸人口 8 ◦之内徑作成比將軸支標外徑還小）°於是’如同本實施形態，藉由支撐部本體冓成軸支撐部本體8 4 Q，及裝配在轴的内捏小=1周圍的環8 41，使得就算吸入口8 〇亦可各易地擴張軸支撐部8 4的外徑。口側:面圖所示’環(Γ周緣部）8 41之吸入心側延寻^ a ’係以位在葉輪的流路7 Q朝向葉輪中广員域S内者為宜。換言之，環吸入口侧的面8 ,比流路7Q之底面7Qa還要#近機殼8側若。此時’就算是因轴承6 ◦之磨耗等而使葉輪之议直偏私於機殼側時，亦能順暢地把從吸入口水引導於葉輪之流路7〇。 81入的又’如第四圖所示，宜在圓錐體狀之突出部8 4 〇 a 外面形成有螺旋狀之階段部8 8。階段部8 8係形成為與葉輪7之旋轉方向X配合的螺旋形狀。此時，能利用圓錐體狀之突出部8 4 0 a賦予自吸入口 8 〇流入的水旋轉而能送至葉輪7側，可更有效率地將混雜有氣泡的水引導至葉輪7。 (第二實施形態）本實施形態的離心泵之基本構造，除了軸支樓部8 4 以外’其餘是與第一實施形態相同’兹對相同部分附予相丄切709 同仏號並省略重覆的說明。如第五、六圖所示，本實施形態之軸支撐部8 4，係，、機殼8各別形成，且在機殼8之内面固定於吸入口 8 〇之蠕部周緣。The driver is preferably provided with a screw-shaped step portion on the outer surface of the above-mentioned conical projection. At this time, the water flowing in from the suction port can be rotated, and the liquid can be discharged more efficiently. [Embodiment] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. (First Embodiment) The basic structure of the centrifugal pump of the present embodiment is the same as the conventional example shown in the eighth embodiment. As shown in the first figure, the centrifugal pump includes: a stator block; a casing 8, 7 13, 29709 has a suction port 80; the shaft support portion 84 is fixed inside the casing 8; the shaft 5 has one end supported by the shaft support portion 84 and the other end supported by the recess portion 40 of the stator block 1; and the impeller 7, The support is rotatable on the shaft 5 by the rotor 6. The stator block 1 is composed of a stator 2 composed of a core and a coil, a control circuit 3, and a partition plate 4 which are formed by insert molding. The stator 2 and the control circuit 3 constitute a driving portion for rotating the impeller 7, and the partition plate 4 is located on the inner peripheral side of the stator 2, and a central portion of the bottom surface thereof is formed with a recessed portion 40 for supporting the other end of the shaft 5 The outer circumference of the shaft 5 is fitted with a rotor 6. The rotor 6 integrally forms the bearing 60 of the inner peripheral portion and the permanent magnet 161 of the outer peripheral side, and the impeller 7 is integrally formed on the side of the casing 8 in the axial direction. The casing 8 is fixed to the stator block 1 by fixing small screws, and a chest chamber for accommodating the impeller 7 is formed between the casing 8 and the partition plate 4. The outer peripheral side of the casing 8 is provided with a discharge port 8 1 (see Fig. 2A), and a suction inlet 80 is provided at the center. The shaft support portion 84 is disposed at a position inside the pump chamber that faces the suction port 80. The configuration of the shaft support portion 8 4 will be described later in detail. The impeller 7 is driven by the drive portion and rotates around the shaft 5 together with the rotor 6. The impeller 7 is provided with a flow path 70 that penetrates from the inner peripheral surface toward the outer peripheral surface, and the water that has flowed into the casing from the suction port 80 is discharged from the discharge port 81 to the outside via the flow path 70. Hereinafter, the shaft support portion 84 will be described in detail. The shaft support portion 84 of the present embodiment is constituted by a shaft support portion main body 840 and a ring 841 which is attached to the outer periphery of the shaft support portion 840 as shown in Figs. 2A and 2B. 8 13.29709 The shaft support portion body 840 is transmitted through a plurality of (three in the illustrated example) support ribs 8 3 extending from the casing 8 at the periphery of the end portion of the suction port 8〇 toward the inside of the casing 8. It is integrated with the casing 8. The shaft support portion main body 840 has a conical projection portion 840a protruding toward the suction port 8b on the side of the suction port 8 side, and has a surface opposite to the suction port 8〇 on the side opposite to the suction port 8〇 A bearing portion 8 5 用来 for supporting one end of the shaft 5. The % 8 41 is an outer diameter of the expansion shaft support portion body 840 to constitute a peripheral portion that extends around the bottom of the projection portion 840a. The ring 8 4 • 1 has a plurality of grooves 8 4 2 corresponding to the support ribs 8 3 , and is fitted around the shaft support body 8 4 以 so that the support ribs 8 3 can be fitted into the grooves 8 4 2 . The ring 8 41 is prevented from rotating by the engagement of the support ribs 8 3 and the grooves 8 4 2, and is further provided by the step portion 8 5 provided at the end portion of the shaft support portion main body 8 4 and the bottom surface of the ring 841 The axial positioning is performed by the engagement of the phase portion (not shown). The ring 8 41 is fixed around the shaft branch body 8 4 例如, for example, by ultrasonic welding. Although the ring 841 is fitted around the shaft support body 8 4 ,, the one side 841 a of the suction port side of the ring 841 is from the bottom of the projection 84 〇 a toward the inner circumference of the flow path 7 of the impeller 7 The opening 7 of the face side extends gently, and the outer diameter of the face 8 4 1 a (i.e., the outer diameter of the ring 841) is greater than the internal control of the suction population 80. The outer peripheral surface of the ring 841 faces the inner peripheral surface of the impeller 7 with a slight gap therebetween. In the centrifugal pump of the present embodiment, since the ring 841 is attached around the shaft support portion main body 84, the outer surface of the shaft support portion body 840 and the inner peripheral surface of the impeller 7 can be filled by the ring 841. The gap makes it difficult for air to accumulate in the casing. Further, the water 'from the suction port 8 〇 toward the flow path 70 of the impeller is smoothly guided to the opening σ of the conical shape and the opening σ of the ring 9 = the surface 8 4 1 3 of the population side. Flow path 7 Ο Liquid. In the vicinity, as a result, it is possible to efficiently discharge the mixed air bubble mold #μ slave casing 8 and the shaft support portion 8 4 to form a body, which is difficult to be 0, and the ratio of the branch portion 8 4 is made. The suction port 8 shaft support (in other words, it is difficult to make the inner diameter of the suction population 8 还 smaller than the outer diameter of the shaft support). Thus, as in the present embodiment, the support portion body is formed into the shaft support portion body 8 4 Q And the ring 8 41 fitted around the shaft pinch small = 1 so that the outer diameter of the shaft support portion 84 can be easily expanded even if the suction port 8 is. The mouth side: the suction of the 'ring (the peripheral edge portion) 8 41 shown in the figure is preferably the side of the flow path 7 Q located in the impeller toward the wide area S of the impeller. In other words, the surface 8 on the side of the ring suction port is closer to the side of the casing 8 than the bottom surface 7Qa of the flow path 7Q. At this time, even if the impeller is directly biased to the casing side due to the wear of the bearing 6 or the like, the flow path from the suction port to the impeller can be smoothly guided. As shown in the fourth figure, it is preferable to form a spiral step portion 8 8 on the outer surface of the conical projection portion 8 4 〇 a . The stage portion 8 8 is formed in a spiral shape that matches the rotation direction X of the impeller 7. At this time, the water that has flowed in from the suction port 8 〇 can be rotated by the conical protruding portion 840a to be sent to the impeller 7 side, and the water mixed with the air bubbles can be more efficiently guided to the impeller 7. (Second Embodiment) The basic structure of the centrifugal pump according to the present embodiment is the same as that of the first embodiment except for the shaft branch portion 8.4, and the same portion is attached to the same portion and the weight is omitted. Overwritten instructions. As shown in Figs. 5 and 6, the shaft support portion 8 4 and the casing 8 of the present embodiment are formed separately, and the inner surface of the casing 8 is fixed to the periphery of the creep portion of the suction port 8 〇.

。更詳言之，軸支撐部8 4，係形成一個塊狀，具備有：圓錐體狀之突出部84〇 a，；設在突出部840 a，之 f部周圍的周緣部8 4 1，；及支撐軸5的-端之軸承部 5〇。軸支撐部8 4，係形成為，周緣部8 4 1，的外杈D 1大於吸入口 8 0之内徑D 2。軸支撐部8 4，，系在機叙8之内面沿軸向安裝於吸入口 8 〇之端部周緣，且利用超音波熔接等方式來固定。、，當軸支撐部8 4，被固定於機殼8時，周緣部8 4 1之吸入口側的面8 41 a，，係自突出部8 4 0 a，之底部朝向流路7 Q之關面側關口 7 i平緩地延伸，周緣部8 4 Γ之外周面係、隔著微小間隙與葉輪7之面呈相對。. More specifically, the shaft support portion 84 is formed in a block shape, and includes: a conical projection portion 84A, and a peripheral portion 814 formed around the projection portion 840a. And a bearing portion 5 of the end of the support shaft 5. The shaft support portion 84 is formed such that the outer circumference D 1 of the peripheral portion 814 is larger than the inner diameter D 2 of the suction port 80. The shaft support portion 8 4 is attached to the peripheral edge of the end portion of the suction port 8 沿 in the axial direction on the inner surface of the machine 8 and is fixed by ultrasonic welding or the like. When the shaft support portion 84 is fixed to the casing 8, the surface 8 41 a of the suction port side of the peripheral portion 814 is from the bottom of the protruding portion 8 4 0 a toward the flow path 7 Q. The closing side opening 7 i extends gently, and the peripheral portion of the peripheral portion 8 4 Γ faces the surface of the impeller 7 with a small gap therebetween.

…本實施形態的離心泵，係能利用周緣部84丄，來填補轴支樓部8 4，㈣面與葉輪7的内周面之間的間隙，、所以空氣難以積存在機殼内。而且，從吸入口 8 〇朝向葉輪之流路7 0的水，係藉由圓錐體狀之突出部8 4 〇 3厂及周緣部84Γ之吸入口侧的面841a，，而順暢地引導至流路7 0的開口 71附近，其結果，能有效率地排出混雜有氣泡之液體。如第一實施形態所述，欲將機殼8及軸體時’在起模方便上，係難以將吸入口 8 〇之内‘作】: 軸支撐部之外徑還小。可是，本實麵態之離心泵，因為 13.2970^ 之口徑D2係能念::二彳與機殼8，所以吸入口8 0 例如第七圖所之大小無關地自由地設小。内❹3維持與第五圖 =:84的軸承部850,之徑D 2設小，藉此提:一^大小’且使吸入口 8 〇的内的泵。 ’、種、准持軸強度且能對應更低流量 41此til',禮亦與第—實施形態同樣地’周緣部8In the centrifugal pump of the present embodiment, the peripheral portion 84 is used to fill the gap between the shaft support portion 84 and the inner surface of the impeller 7, so that it is difficult to accumulate air in the casing. Further, the water from the suction port 8 〇 toward the flow path 70 of the impeller is smoothly guided to the flow by the surface 841a on the suction port side of the conical projection portion 8 4 〇3 and the peripheral portion 84Γ. In the vicinity of the opening 71 of the road 70, as a result, the liquid mixed with the air bubbles can be efficiently discharged. As described in the first embodiment, when the casing 8 and the shaft body are to be used, it is difficult to make the inside of the suction port 8 :: the outer diameter of the shaft support portion is small. However, in the centrifugal pump of the present embodiment, since the diameter D2 of 13.2970^ can be read: the second casing and the casing 8, the suction port 80 is freely set to be small irrespective of the size of the seventh figure. The inner bore 3 is maintained and the bearing portion 850 of the fifth figure =: 84, and the diameter D 2 is set small, thereby raising the pump inside the suction port 8 〇. ‘, kind, quasi-axis strength and can correspond to lower flow rate 41 til', also in the same manner as the first embodiment ‘peripheral part 8

rb 41 a ，係以使葉輪之流路γ 〇位在於葉輪之中心側延伸的領域内者為宜。嫂在圓錐體狀之突出部840a，之外面亦宜形成螺旋狀的階段部。惟’以上所述，僅為本發明最 =本發：’本發明之所有範圍應以下述之申請=Rb 41 a is preferably in a field in which the flow path γ of the impeller is extended on the center side of the impeller. It is preferable that the outer surface of the conical projection 840a is formed in a spiral step portion. However, as mentioned above, it is only the most recent invention of the present invention: 'All the scope of the present invention should be as follows:

二’凡°於本發明申請專利範®之精神與其類似變化之實施例，皆應包含於本發明之孰 ==之r内，可輕易思及之變化或修= 在以下本案之專利範圍。【圖式簡單說明】 ^圖係本發明之第—實施形態所涉及之離心泵的剖面 ^A圖係第-圖的離心泵之機殼與環之局部分離前視圖係表示將環裝配於第二A _機殼之狀態的局部刀離如視圖。 12 13:29709 第三圖係第一圖之要部放大圖。第四圖係表示在第一圖的突出部形成螺旋狀的階段部之一例的局部前視圖。第五圖係本發明之第二實施形態所涉及的離心泵之剖面圖。第六圖係第五圖的離心泵之機殼與軸支撐部之剖面圖。第七圖係表示使第五圖之離心泵中的吸入口作成小口徑的變形例之剖面圖。第八圖係習知例的離心泵之剖面圖。【主要元件符號說明】 1定子塊 2定子 3控制電路 4隔間板 4 0凹部 5轴 6轉子 6 0軸承 61永久磁鐵 7葉輪 7 0流路 7 1開口 8機殼 8 0吸入口 13 1329709 8 3支撐肋 8 4、8 4’軸支撐部 8 4 0軸支撐部本體 840a、840a’ 突出部 8 4 1環 8 4 Γ周緣部 841a、841a’吸入口側的面 8 5 0、8 5 0 ’軸承部 14The embodiments of the present invention and the similar variations of the present invention should be included in the 孰 == r of the present invention, and can be easily changed or repaired in the following patent scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a centrifugal pump according to a first embodiment of the present invention, and a partial separation front view of a casing and a ring of a centrifugal pump of the first embodiment shows a ring assembly. The partial knife of the state of the second A _ casing is as shown in the view. 12 13:29709 The third picture is an enlarged view of the main part of the first picture. The fourth figure is a partial front view showing an example of a stage portion in which the protruding portion of the first figure is formed in a spiral shape. Fig. 5 is a cross-sectional view showing a centrifugal pump according to a second embodiment of the present invention. The sixth drawing is a cross-sectional view of the casing and the shaft support portion of the centrifugal pump of the fifth drawing. Fig. 7 is a cross-sectional view showing a modification in which the suction port in the centrifugal pump of the fifth embodiment is formed into a small diameter. The eighth figure is a cross-sectional view of a centrifugal pump of a conventional example. [Main component symbol description] 1 stator block 2 stator 3 control circuit 4 compartment board 4 0 recess 5 shaft 6 rotor 6 0 bearing 61 permanent magnet 7 impeller 7 0 flow path 7 1 opening 8 casing 8 0 suction port 13 1329709 8 3 support ribs 8 4, 8 4' shaft support portion 8 40 shaft support portion body 840a, 840a' protrusion portion 8 4 1 ring 8 4 Γ peripheral portion 841a, 841a' suction port side surface 8 5 0, 8 5 0 'bearing part 14

Claims

1329709 X. Patent application scope: 1. A centrifugal pump, comprising: a casing having a suction port; a shaft support portion fixed on the inner side of the casing; a shaft supported by the shaft support portion; the impeller being supported to be Rotating on the shaft, and having a flow path penetrating from the inner peripheral surface toward the outer peripheral surface, the liquid flowing into the casing from the suction port is discharged to the outside through the flow path; and the driving portion is used for The shaft support portion includes a conical protruding portion that is formed on the surface on the suction port side and protrudes toward the suction port, and a peripheral portion that is provided around the bottom of the protruding portion. The surface of the peripheral portion on the suction port side extends from the bottom of the protruding portion toward the opening on the inner peripheral surface side of the flow path of the impeller, and the outer diameter is larger than the inner diameter of the suction port. 2. The centrifugal pump according to claim 1, wherein the shaft support portion includes: a shaft support portion body integrally formed with the casing and having the above-described conical projection; and being mounted on the shaft support portion The outer circumference of the body is used to form a ring of the peripheral portion. 3. The centrifugal pump according to claim 1, wherein the shaft support portion is formed separately from the casing, and an inner surface of the casing is fixed to a peripheral edge of the suction port. 15 1329709

4. The centrifugal pump according to claim 1, wherein the surface of the peripheral portion on the suction port side is located in a region in which the flow path of the impeller extends toward the center side of the impeller. 5. The centrifugal pump according to claim 1, wherein a spiral step portion is formed on an outer surface of the tapered portion. 16