CN201208423Y - Pump and machine unification implanted micro axial flow blood pump - Google Patents

Abstract

The utility model belongs to the technology field of medical devices, in particular to an embedded axial flow blood pump with the integration of a pump and a motor. The embedded axial flow blood pump is composed of two major parts of the brushless motor and the axial flow blood pump. The brushless motor is composed of a stator iron core 2 which is fixed on an outer shell 1 and a motor support 4, a stator coil 3 and a rotor cylindrical magnetic steel 5; the axial flow blood pump is constituted by connecting a propeller shaft integrated series rotor 9 with a left-handed outlet stator 13 and a right-handed inlet stator 15 through a ceramic bearing 14. The rotor cylindrical magnetic steel 5 of the motor and a front series small rotor 8 are fixed and connected together; the left-handed outlet stator 13, the right-handed inlet stator 15 and the motor support 4 are connected together, thereby becoming the axial flow blood pump with the integration of the pump and the motor. The embedded axial flow blood pump integrates the pump and the motor and has small size and light weight, blood is branched by a main runner and a branch runner, the flow is smooth and has no congestion or thrombosis, the operation is balance, and the use is comfortable, thereby being completely applicable to be used as an embedded ventricular assist device.

Description

Translated fromChinese

泵机合一植入式微型轴流血泵Pump-in-one implantable miniature axial flow blood pump

技术领域technical field

本实用新型属于医疗器械技术领域，具体涉及一种心室辅助装置，特别涉及一种可植入式心室辅助装置。The utility model belongs to the technical field of medical devices, in particular to a ventricular assisting device, in particular to an implantable ventricular assisting device.

背景技术Background technique

心力衰竭是心血管出院病人最常见的诊断，也是医疗费用最高的疾病，国际上已将心衰作为本世纪需要解决的一项重要课题。由于供体的缺乏，大约30％准备接受心脏移植的病人在等待供心过程中死于心功能恶化，心室辅助装置(VAD)的出现和发展，使得心衰的治疗有新的途经，从1981年开始，美国国立卫生研究院(NIH)起动RFDs计划(a RequestForProposals)用于发展“用于长期心脏支持的可植入式能使病人自由移动，电动能源的心室辅助装置”。到目前为止共投入超过400亿美元的资金以支持心室辅助装置的研发。2006年欧洲心衰指南已将心室辅助装置作为心衰治疗的方法之。经过多年的研究，目前国际上已经有数种产品应用于临床，主要用于心脏移植的过渡。心功能的恢复甚至永久性替代治疗，但进口产品价格昂贵，使得心室辅助装置的国产化研制迫在眉睫，泵体合一可植入式轴流血泵则是心室辅助装置的关键核心部件。Heart failure is the most common diagnosis of cardiovascular discharged patients, and it is also the disease with the highest medical expenses. Heart failure has been regarded as an important issue to be solved in this century in the world. Due to the lack of donors, about 30% of patients who were about to receive a heart transplant died of worsening cardiac function while waiting for the donor heart. The emergence and development of the ventricular assist device (VAD) provided a new way for the treatment of heart failure. Since 1981 Beginning in 2010, the National Institutes of Health (NIH) launched the RFDs program (a Request For Proposals) for the development of "implantable patient-free, electrically powered ventricular assist devices for long-term cardiac support". To date, more than $40 billion has been invested in the development of ventricular assist devices. The 2006 European heart failure guidelines have included ventricular assist devices as one of the methods of heart failure treatment. After years of research, several products have been used clinically in the world, mainly for the transition of heart transplantation. Restoration of cardiac function and even permanent replacement therapy, but imported products are expensive, making the development of localized ventricular assist devices imminent. The pump-body-in-one implantable axial flow blood pump is the key core component of ventricular assist devices.

发明内容Contents of the invention

本实用新型发明的目的在于提供一种可应用于手术治疗心衰终末期可植入式心室辅助装置的关键核心部件，泵机合一可植入式微型轴流血泵。The purpose of the invention of the utility model is to provide a key core component of an implantable ventricular assist device that can be applied to the surgical treatment of end-stage heart failure.

由于这种心室辅助装置要植入体内，因此对其主要部件的泵机合一微型轴流血泵的重量和尺寸限制苛刻。Since this ventricular assist device is to be implanted in the body, the weight and size of the main component of the pump mechanism integrated into a miniature axial flow blood pump are severely restricted.

本实用新型设计的泵机合一植入式轴流血泵，设计方案如下：The pump unit-in-one implantable axial flow blood pump designed by the utility model has the design scheme as follows:

1.新型的血液流道设计1. New blood channel design

一般心室辅助装置的泵系统(DeBakey VAD，Berlin Heart Incor I和国产VZ-II A型)其电机磁钢转子和血泵转子同置于血液流道中，这样在血液流道中多了个转子磁钢，减小了血液流道面积，影响了血流量，而且电机定子和转子间的气隙也增大，所需功率也增大。In general ventricular assist device pump systems (DeBakey VAD, Berlin Heart Incor I and domestic VZ-II A type), the motor magnet rotor and the blood pump rotor are placed in the blood flow channel, so that there is an additional rotor magnet in the blood flow channel , the area of the blood flow channel is reduced, which affects the blood flow, and the air gap between the motor stator and the rotor is also increased, and the required power is also increased.

本实用新型的流道特点是血液由置于电机转子圆柱磁钢5内孔的微型血泵转子-轴一体化的串列转子9驱动，形成φ10～11mm的主流道和间隙为φ0.2～0.25mm的支流道。在主流道内没有电机磁钢转子，流道阻碍小，流道面积大，可保证大血流量从主流道通过，即从园子圆柱磁钢5的内孔通过，转子圆柱磁钢5的内孔直径为10-11mm；在支流道内没有任何阻碍物阻碍血液流过，且由于支流道间隙很小，无刷电机定子线圈3和转子圆柱磁钢5的气隙也很小，从而显著减小无刷直流电机本机和轴流血泵的体积和重量，适合于植入式心脏辅助装置。(图1)The flow path of the utility model is characterized in that the blood is driven by a micro-blood pump rotor-axis integratedtandem rotor 9 placed in the inner hole of the motor rotor cylindricalmagnetic steel 5, forming a main flow channel of φ10-11mm and a gap of φ0.2- 0.25mm tributary channel. There is no motor magnetic steel rotor in the main flow channel, the flow channel obstruction is small, and the flow channel area is large, which can ensure that a large blood flow passes through the main flow channel, that is, through the inner hole of the garden cylindricalmagnetic steel 5, and the diameter of the inner hole of the rotor cylindricalmagnetic steel 5 It is 10-11mm; there is no obstacle in the branch channel to hinder the flow of blood, and because the gap between the branch channel is small, the air gap between thestator coil 3 of the brushless motor and the rotorcylindrical magnet 5 is also very small, thereby significantly reducing the brushless The size and weight of the DC motor native and the axial flow blood pump are suitable for implantable cardiac assist devices. (figure 1)

2.转子叶片的设计；2. Design of rotor blades;

有鉴于泵机合一轴流血泵其流道狭长，转子的叶片直径受到限制，且流道又分为主流道和支流道。本实用新型采用了船用螺旋桨特种推进器中的串列螺旋桨概念，将轴流血泵的转子设计为串列转子形式。所谓串列转子是指两只不同转子安装在同一根轴上，且按同一转速旋转，这类串列转子形式特别适用于植入式轴流血泵流道狭长，转子直径受限制的情况。具体来说，本实用新型中串列转子9由前置小转子8和后置大转子10同轴固定组成，见图3所示。前置小转子8在前，直径为10-11mm，轴向长度为21-22mm，螺距为35-37mm，后置大转子10在后，直径为18-19mm，轴向长度为10-11mm，螺距为27-28mm，轴的直径为4-5mm。In view of the long and narrow flow path of the axial blood pump combined with the pump mechanism, the diameter of the blades of the rotor is limited, and the flow path is divided into a main flow path and a branch flow path. The utility model adopts the tandem propeller concept in the marine propeller special propeller, and designs the rotor of the axial flow blood pump in the form of a tandem rotor. The so-called tandem rotor means that two different rotors are installed on the same shaft and rotate at the same speed. This type of tandem rotor is especially suitable for implantable axial blood pumps with narrow and long flow channels and limited rotor diameters. Specifically, thetandem rotor 9 in the present invention consists of a frontsmall rotor 8 and a rearlarge rotor 10 coaxially fixed, as shown in FIG. 3 . The frontsmall rotor 8 is in the front, the diameter is 10-11mm, the axial length is 21-22mm, the pitch is 35-37mm, the rear large rotor is 10, the diameter is 18-19mm, the axial length is 10-11mm, The pitch is 27-28mm and the diameter of the shaft is 4-5mm.

由于本实用新型泵机合一植入式轴流血泵的流道分为主流道和支流道，而且主流道和支流道大小尺寸悬殊，采用前置小转子在前，后置大转子在后，可保证血液在进入流道时先受到小转子转动叶片的作用，保证绝大部分血液在进入流道时，从主流道通过，而微量血液则借助于设置在后面的大转子的叶梢部分作用通过，这样可以保证血液在主、支流道内顺利分叉，流畅通过，不产生拥塞血栓现象。Since the flow channel of the implanted axial flow blood pump of the utility model is divided into a main flow channel and a branch flow channel, and the size of the main flow channel and the branch flow channel is very different, the front small rotor is in the front, and the rear large rotor is in the back. , which can ensure that the blood is firstly affected by the rotating blades of the small rotor when entering the flow channel, and ensure that most of the blood passes through the main channel when entering the flow channel, while a small amount of blood passes through the blade tip of the large trochanter arranged behind The effect is passed, which can ensure that the blood bifurcates smoothly in the main and tributary channels, passes through smoothly, and does not produce congestion and thrombus.

为进一步提高植入式轴流血泵的效率，增大压头，本实用新型大、小串列转子叶片的叶切面采用船用导管螺旋桨的机翼形叶片切面形式(见图4)，取代一般泵的平板叶切面形式。机翼形叶切面相比平板形叶切面，由于血液流过机翼形叶切面时，叶切面叶面上出现正压，叶切面叶背上出现负压，叶面、叶背的压力差可提高血泵效率，增大压头。In order to further improve the efficiency of the implanted axial flow blood pump and increase the pressure head, the cutting surface of the large and small tandem rotor blades of the utility model adopts the wing-shaped blade cutting surface form of a marine duct propeller (see Figure 4), replacing the general pump in the form of a flat leaf cutaway. Compared with the flat leaf section, the wing-shaped leaf section has positive pressure on the leaf section and negative pressure on the leaf back when the blood flows through the wing-shaped section, and the pressure difference between the leaf surface and the leaf back can be reduced. Improve blood pump efficiency and increase pressure head.

3.电机定子的设计3. Design of motor stator

心室辅助装置不但要求体积小，重量轻，而且还要求装置运转必须平衡、振动小、噪声低，以提高使用时的舒适性。如图2所示，本实用新型泵机合一植入式轴流血泵的无刷电机本体的定子采用了二相导通、三相六状态的导电模型，这样不但提高了绕组的利用率，缩小了体积和重量，而且减小了磁状态角，减小了无刷电动机的换流带来的本质上的转动波动；定子绕组采用空心杯绕组，不但解决了小尺寸的定子下线困难的问题，而且定子铁芯不再有齿槽，彻底消除了齿谐波磁场带来的本质上的转动波动。Ventricular assist devices not only require small size and light weight, but also require balanced operation, low vibration, and low noise to improve comfort during use. As shown in Figure 2, the stator of the brushless motor body of the implantable axial flow blood pump of the utility model adopts a two-phase conduction, three-phase six-state conductive model, which not only improves the utilization rate of the winding , the size and weight are reduced, and the magnetic state angle is reduced, which reduces the essential rotation fluctuation caused by the commutation of the brushless motor; the stator winding adopts the hollow cup winding, which not only solves the difficulty of the small-sized stator off-line problem, and the stator core no longer has cogging, which completely eliminates the essential rotation fluctuation caused by the tooth harmonic magnetic field.

无刷电机转子采用具有剩磁感应强度高的钕钢硼永磁材料，且采用径向充磁、一对极的园柱形柱钢，从而可在空心杯绕组这种大的电磁气隙下，仍能产生强的气隙磁场，缩小了电动机的体积和重量，一对极的整体园柱形磁钢更易保证质量的均匀，减小了高速运动下的动不平衡，且因不存在单边磁拉力，故运转平稳，提高了使用的舒适性。The brushless motor rotor is made of neodymium steel boron permanent magnet material with high residual magnetic induction intensity, and adopts radially magnetized, one-pole cylindrical column steel, so that it can be used under the large electromagnetic air gap of the hollow cup winding. It can still generate a strong air gap magnetic field, which reduces the volume and weight of the motor. The overall cylindrical magnetic steel with one pair of poles is easier to ensure uniform quality, and reduces the dynamic unbalance under high-speed motion, and because there is no unilateral Magnetic pull, so the operation is stable and the comfort of use is improved.

考虑到此专用的泵机合一植入式轴流血泵用于植入式心室辅助装置，对结构的密封性有高的要求，若采用常规的无刷直流电动机位置传感器，则因传感器定子霍尔元件出线过多(至少5根)，带来引线密封以及引线材料与人体排异的作用，本实用新型采用电路实现可鉴别转子位置和自起动的功能，起到了位置传感器的功能，可以取消常规无刷常流电动机必备的位置传感器，这样既减小密封的难度，提高了可靠性，又简化了结构，缩小了体积。Considering that the special pump combined with an implantable axial flow blood pump is used for implantable ventricular assist devices, it has high requirements on the sealing of the structure. If a conventional brushless DC motor position sensor is used, the stator of the sensor will There are too many Hall elements (at least 5 wires), which will lead to the sealing of the lead wires and the rejection of the lead material and the human body. The utility model uses a circuit to realize the functions of identifying the rotor position and self-starting, and plays the role of a position sensor. The necessary position sensor of the conventional brushless constant current motor is canceled, which not only reduces the difficulty of sealing, improves the reliability, but also simplifies the structure and reduces the volume.

根据上述设计，本实用新型的泵机合一植入式轴流血尖的具体结构如图1所示。它由外壳1、定子铁芯2、定子线圈3、电机支架4、转子圆柱磁钢5、浆轴一体化串列转子9、左旋出口定子13和右旋入口定子15组合构成；其中，浆轴一体化串列转子9由前置小转子8和后置大转子10同轴固定组成，外壳1内依次是定子铁芯2、转子线圈3；浆轴一体化串列转子9穿过转子圆柱磁钢5的中心洞孔，轴的两端由陶瓷轴承14分别固定于左旋出口定子13和右旋入口定子15中，左旋出口定子13、右旋入口定子15分别与电机支架4两端固定。转子圆柱磁钢5设置于转子线圈3内中间部位，对应于串列转子9的前置小转子8的位置，并与前置小转子8固定成一体；串列转子9与转子线圈3的内壁和转子圆柱磁钢5的中心洞孔内壁构成血液的主流道11和12，转子圆柱磁钢5的外壁与定子线圈3的内壁之间构成血液的支流道6和7。According to the above-mentioned design, the specific structure of the implanted axial flow blood tip integrated with the pump of the present invention is shown in FIG. 1 . It is composed of acasing 1, astator core 2, astator coil 3, amotor bracket 4, a rotor cylindricalmagnetic steel 5, a tandem rotor integrated with apaddle shaft 9, a left-handed outlet stator 13 and a right-handed inlet stator 15; among them, the paddle shaft The integratedtandem rotor 9 is composed of a frontsmall rotor 8 and a rearlarge rotor 10 coaxially fixed. Inside thecasing 1 are thestator core 2 and therotor coil 3 in sequence; The center hole ofsteel 5, the two ends of axle are respectively fixed in left-handed outlet stator 13 and right-handed inlet stator 15 byceramic bearing 14, left-handed outlet stator 13, right-handed inlet stator 15 are respectively fixed withmotor support 4 two ends. The rotor cylindricalmagnetic steel 5 is arranged in the middle part of therotor coil 3, corresponding to the position of the frontsmall rotor 8 of thetandem rotor 9, and is fixed with the frontsmall rotor 8; thetandem rotor 9 and the inner wall of therotor coil 3 Themain channels 11 and 12 of the blood are formed with the inner wall of the central hole of the rotor cylindricalmagnetic steel 5, and thetributary channels 6 and 7 of blood are formed between the outer wall of the rotor cylindricalmagnetic steel 5 and the inner wall of thestator coil 3.

附图说明Description of drawings

图1为本实用新型的结构图示(剖面图)。Fig. 1 is a structural illustration (sectional view) of the present utility model.

图2为本实用新型的浆轴承一体化串列转子结构图。Fig. 2 is a structure diagram of the tandem rotor integrated with the slurry bearing of the present invention.

图3为本实用新型的浆轴承一体化串列转子的叶切面及受力图示。Fig. 3 is a blade cut surface and force diagram of the integrated tandem rotor with slurry bearing of the present invention.

图4本实用新型定子、转子结构的径向剖面图示。Fig. 4 is a radial section illustration of the stator and rotor structure of the utility model.

图中标号：1.外壳，2.定子铁芯，3.定子线圈，4.电机支架，5.转子圆柱磁钢，6、7.支流道，8.前置串列小转子，9.浆轴一体化串列转子，10.后置串列大转子，11、12.主流道，13.左旋出口定子，14.陶瓷轴承，15.右旋入口定子，16.血流方向，17.转子轴，18.转子叶片叶切面的叶面，19.转子叶片叶切面的叶背，20.叶面的压力分布线，21.叶背的压力分布线。Labels in the figure: 1. Shell, 2. Stator core, 3. Stator coil, 4. Motor bracket, 5. Rotor cylindrical magnet, 6, 7. Branch channel, 8. Front tandem small rotor, 9. Slurry Shaft-integrated tandem rotor, 10. Rear tandem large rotor, 11, 12. Main channel, 13. Left-handed outlet stator, 14. Ceramic bearing, 15. Right-handed inlet stator, 16. Blood flow direction, 17. Rotor Shaft, 18. leaf surface of rotor blade cut surface, 19. blade back of rotor blade leaf cut surface, 20. pressure distribution line of blade surface, 21. pressure distribution line of blade back.

具体实施方式Detailed ways

如附图1所示，泵机合一轴流血泵由无刷电机和轴流血泵二大部分组成。无刷电机由固定在外壳1和电机支架4上的定子铁芯2、定子线圈3和转子圆柱磁钢5组成；轴流血泵由浆轴一体化串列转子9通过陶瓷轴承14与左旋出口定子13和右旋入口定子15连接。电机转子圆柱磁钢5与前置串列小转子8固定连成一体；左旋出口定子13和右旋入口定子15与电机支架4连成一体，从而成为泵机合一轴流血泵。当电机的定子线圈3通电后，在定子线圈3的内圆与转子圆柱磁钢5的外圆之间的气隙中产生旋转磁场带动转子圆柱磁钢5旋转，并驱动与转子圆柱磁钢5连成一体的浆轴一体化串列转子9一起转动，血液便从泵体的进口吸入，从出口流出。由于轴流血泵的串列转子9由前置串列小转子8和后置串列大转子10组成，血液进入泵体内先受到前置串列小转子8的作用，绝大部分从主流道11、12通过，而微量血液则借助于设置在后面的后置串列大转子10的叶梢部分作用从支流道6、7通过，这样可以保证进入泵体内的血流在进入主、支流道时顺利分叉，流畅通过，不产生血液拥堵血栓现象。As shown in accompanying drawing 1, the pump mechanism integrated axial flow blood pump is composed of brushless motor and axial flow blood pump. The brushless motor is composed of thestator core 2, thestator coil 3 and the rotor cylindricalmagnetic steel 5 fixed on thecasing 1 and themotor bracket 4; the axial flow blood pump is composed of atandem rotor 9 integrated with a paddle shaft through aceramic bearing 14 and a left-handed outlet.Stator 13 is connected with right-handed inlet stator 15 . The motor rotor cylindricalmagnetic steel 5 is fixedly connected with the front tandemsmall rotor 8; the left-handed outlet stator 13 and the right-handed inlet stator 15 are connected with themotor bracket 4, thereby becoming a pump mechanism integrated axial flow blood pump. When thestator coil 3 of the motor is energized, a rotating magnetic field is generated in the air gap between the inner circle of thestator coil 3 and the outer circle of the rotorcylindrical magnet 5 to drive the rotorcylindrical magnet 5 to rotate, and drive the rotorcylindrical magnet 5 to rotate. The combined paddle shaft integratedtandem rotor 9 rotates together, and the blood is sucked in from the inlet of the pump body and flows out from the outlet. Since thetandem rotor 9 of the axial flow blood pump is composed of the front tandemsmall rotor 8 and the rear tandemlarge rotor 10, the blood entering the pump body is first affected by the front tandemsmall rotor 8, and most of it flows from the main channel. 11 and 12 pass through, while a small amount of blood passes through thebranch channels 6 and 7 by means of the blade tip part of the rear-mounted tandemlarge rotor 10 arranged at the back, so that the blood flow entering the pump body can be ensured before entering the main and branch channels. When the bifurcation is smooth, it passes through smoothly, without blood congestion and thrombus phenomenon.

本实用新型设计制造了一种泵机合一植入式轴流血泵，其尺寸为φ29.6mm×72mm，重量158g。其中轴流泵尺寸为φ18.5mm×72mm，前置串列小转子8为φ10mm×21mm，后置串列大转子10为φ18mm×10mm，转子圆柱磁钢5内径为φ10mm，外径为φ17.6mm，长度为21mm，这样主流道φ10mm，支流道间隙0.25mm。该实例已成功地应用于植入小牛胸腔内的动物实验，泵转速为9000转/分时，血流量达5升/分，完全适合于植入式心室辅助装置的应用。The utility model designs and manufactures an implantable axial-flow blood pump with a pump in one, the size of which is φ29.6mm×72mm, and the weight is 158g. Among them, the size of the axial flow pump is φ18.5mm×72mm, the front tandemsmall rotor 8 is φ10mm×21mm, the rear tandemlarge rotor 10 is φ18mm×10mm, the inner diameter of the rotor cylindricalmagnetic steel 5 is φ10mm, and the outer diameter is φ17. 6mm, the length is 21mm, so the main channel φ10mm, the branch channel gap 0.25mm. This example has been successfully applied to animal experiments implanted in calf thorax. When the pump speed is 9000 rpm, the blood flow can reach 5 liters/min, which is completely suitable for the application of implantable ventricular assist devices.

无刷电机的结构如图4所示，定子采用二相导通，三相六状态的导电模式，定子铁芯2中的定子线圈3分为三块：B-Y线圈，A-X线圈，C-Z线圈，定子绕组采用空心杯绕组形式，转子圆柱磁钢5采用钕钢硼永磁材料，由径向充磁。The structure of the brushless motor is shown in Figure 4. The stator adopts two-phase conduction, three-phase six-state conduction mode, and thestator coil 3 in thestator core 2 is divided into three parts: B-Y coil, A-X coil, C-Z coil, stator The winding is in the form of a hollow cup winding, and the rotor cylindricalmagnetic steel 5 is made of neodymium steel boron permanent magnet material, which is magnetized by radial direction.

Claims (3)

1, a kind of pump machine unification implanted micro axial flow blood pump, comprise brushless electric machine and miniature blood pump two parts, it is characterized in that it is constituted by shell (1), stator core (2), stator coil (3), electric machine support (4), rotor cylinder magnet steel (5), slurry axle integrated tandem rotor (9), left-handed outlet stator (13) and dextrorotation inlet stator (15), wherein, the integrated tandem rotor of slurry axle (9) is by preposition lesser trochanter (8) and rearmounted greater trochanter (10) is coaxial fixedly forms, and is stator core (2), rotor coil (3) successively in the shell (1); The slurry integrated tandem rotor of axle (9) passes the center hole of rotor cylinder magnet steel (5), the two ends of axle are individually fixed in left-handed outlet stator (13) and the dextrorotation inlet stator (15) by ceramic bearing (14), and left-handed outlet stator (13), dextrorotation inlet stator (15) are fixed with electric machine support (4) two ends respectively; Rotor cylinder magnet steel (5) is arranged at the interior middle part of rotor coil (3), corresponding to the position of the preposition lesser trochanter (8) of tandem rotor (9), and is fixed into one with preposition lesser trochanter (8); Constitute the branch flow passage (6 and 7) of blood between the outer wall of sprue (11 and 12) the rotor cylinder magnet steel (5) of the center hole inwall formation blood of the inwall of tandem rotor (9) and rotor coil (3) and rotor cylinder magnet steel (5) and the inwall of stator coil 3.

2, pump machine unification implanted micro axial flow blood pump according to claim 1 is characterized in that the blade section of the described slurry incorporate tandem rotor of axle (9) adopts airfoil.

3, pump machine unification implanted micro axial flow blood pump according to claim 1, the stator employing two that it is characterized in that the brshless DC motor body is conducted, the conduction mode of three-phase six states, stator coil (3) adopts the drag cup winding, and rotor cylinder magnet steel (5) adopts rubidium ferrum B permanent magnetic material.

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