CN114042241A

CN114042241A - Magnetic suspension pump

Info

Publication number: CN114042241A
Application number: CN202111357981.1A
Authority: CN
Inventors: 娄厦; 周彦; 余顺周
Original assignee: Shenzhen Core Medical Technology Co Ltd
Current assignee: Shenzhen Core Medical Technology Co Ltd
Priority date: 2021-11-16
Filing date: 2021-11-16
Publication date: 2022-02-15
Anticipated expiration: 2041-11-16
Also published as: CN114042241B

Abstract

The invention belongs to the field of medical instruments, and particularly relates to a magnetic suspension pump which comprises a pump shell, a fixed magnet, an impeller, a movable magnet, a rotor magnet, a driving part and a magnetic force part, wherein the impeller is arranged around the fixed magnet and can rotate around a central column, the movable magnet and the rotor magnet are fixedly connected to the impeller, the movable magnet is arranged around the fixed magnet and has a first magnetic force effect with the fixed magnet, the rotor magnet is arranged around the central column, a stator of the driving part can generate a rotating magnetic field for driving the rotor magnet to rotate, attraction force is formed between the stator and the rotor magnet, the magnetic force part is arranged between the stator and the impeller, the magnetic force part and the movable magnet are arranged oppositely, and a second magnetic force effect is formed between the magnetic force part and the movable magnet. The attractive force, the first magnetic action, and the second magnetic action can work together to suspend the impeller within the fluid chamber. The magnetic suspension pump is good in economy and capable of reducing resource waste.

Description

Magnetic suspension pump

Technical Field

The invention relates to the technical field of medical instruments, in particular to a magnetic suspension pump.

Background

The artificial heart (or blood pump) is a medical apparatus which uses a biological mechanical means to partially or completely replace the blood pumping function of the heart and maintain the blood circulation of the whole body, and the artificial heart can be divided into an extracorporeal type and an implantable type according to the implantation position. The implanted artificial heart is used for patients with end-stage chronic heart failure and replaces the heart function for a long time. The in vitro artificial heart (middle-short term extracorporeal circulation auxiliary equipment) is used for transition treatment of patients with acute heart failure, plays a role in replacing the heart function in the middle-short term, enables the patients to pass through the critical period, and helps the patients to recover.

The blood pump with non-contact suspension support is the mainstream trend in the field of artificial heart at present, and the non-contact suspension support mode comprises magnetic suspension support, hydraulic suspension support and mixed support combining the two modes. The impeller of the blood pump adopting the magnetic suspension support mode is suspended in the fluid cavity by means of magnetic rotation, the pumping function of the blood pump is realized by the suspension rotation of the impeller, and the problem of damage of a mechanical bearing to blood is reduced due to the suspension rotation of the impeller, so that the magnetic suspension support mode becomes one of mainstream support modes of the existing blood pump.

Because blood needs to be introduced into the fluid cavity, in order to avoid cross infection, one blood pump is usually only used by one patient, particularly for extracorporeal circulation type short-term treatment, the use mode has poor economy and can cause great resource waste, and although a separated pump head is proposed at present, the economy is still poor, and the caused resource waste is still great.

Disclosure of Invention

In view of this, it is desirable to provide a magnetic levitation pump which is economical and can reduce resource waste.

To achieve the above object, the present invention provides a magnetic levitation pump comprising:

a pump housing provided with a fluid chamber;

the fixed magnet is arranged in the fluid cavity and is fixedly connected with the pump shell;

the impeller is arranged in the fluid cavity, is arranged around the fixed magnet and can rotate around the fixed magnet;

the moving magnet is fixedly connected to the impeller, surrounds the fixed magnet, and has a first magnetic action with the fixed magnet;

a rotor magnet fixedly connected to the impeller;

a driving part including a stator capable of generating a rotating magnetic field that drives the rotor magnet to rotate, the stator and the rotor magnet having an attractive force therebetween;

the magnetic force piece is arranged between the stator and the impeller, and a second magnetic force action is realized between the magnetic force piece and the moving magnet;

wherein the attractive force, the first magnetic action, and the second magnetic action are collectively operable to levitate the impeller within the fluid chamber.

Optionally, the first magnetic action is a repulsive force, the first magnetic action is capable of generating a first acting force on the impeller, the direction of the first acting force is inclined relative to the magnetizing direction of the fixed magnet, the first acting force has a first component force parallel to the magnetizing direction of the fixed magnet, and the direction of the first component force is towards or away from the stator; the second magnetic action is capable of generating at least a force on the impeller directed opposite to the direction of the first force component, wherein the attraction force, the first force component, and the second magnetic action are capable of collectively suspending the impeller in the fluid chamber in a direction parallel to the charging direction of the stationary magnet.

Optionally, the first component force is directed to the direction of the stator, and as the distance between the impeller and the stator changes, the rate of change of the magnitude of the second magnetic force action between the magnetic member and the moving magnet is greater than the rate of change of the magnitude of the first magnetic force action between the moving magnet and the fixed magnet.

Optionally, the magnetic density of the magnetic member is greater than the magnetic density of the fixed magnet.

Optionally, the magnetizing direction of the moving magnet is parallel to the rotating shaft of the impeller, the magnetizing direction of the fixed magnet is the same as the magnetizing direction of the moving magnet, and the magnetic poles on the sides of the magnetic member and the moving magnet, which are close to each other, are the same.

Optionally, in a magnetizing direction of the moving magnet, the moving magnet has a first magnetic pole end and a second magnetic pole end away from the first magnetic pole end, and the first magnetic pole end is close to the stator; in the magnetizing direction of the fixed magnet, the fixed magnet is provided with a third magnetic pole end and a fourth magnetic pole end which is far away from the third magnetic pole end, the third magnetic pole end is close to the stator, the magnetic poles of the third magnetic pole end and the first magnetic pole end are the same, the magnetic poles of the fourth magnetic pole end and the second magnetic pole end are the same, and one side of the magnetic force piece, which is close to the impeller, is provided with the magnetic pole which is the same as the first magnetic pole end of the moving magnet;

wherein the first magnetic-pole end of the moving magnet is closer to the stator than the third magnetic-pole end of the fixed magnet; during rotation of the impeller, the second magnetic-pole end of the moving magnet is closer to the stator than the fourth magnetic-pole end of the fixed magnet, and the third magnetic-pole end of the fixed magnet is closer to the stator than the second magnetic-pole end of the moving magnet.

Optionally, the second magnetic force acts as a repulsive force, the magnetizing direction of the magnetic member is inclined with respect to the magnetizing direction of the fixed magnet, and the second magnetic force acts on the impeller and can also generate an acting force which is perpendicular to the magnetizing direction of the fixed magnet and points to the direction of the fixed magnet.

Optionally, the angle of inclination of the magnetizing direction of the magnetic member with respect to the magnetizing direction of the fixed magnet is 10 ° to 80 °.

Optionally, the angle of inclination of the magnetizing direction of the magnetic member with respect to the magnetizing direction of the fixed magnet is 30-60 °.

Optionally, the magnetic member is a conical ring, a large opening end of the magnetic member faces the impeller, a magnetizing direction of the magnetic member is directed to the other side from one of an outer surface and an inner surface of the conical ring, the magnetizing direction of the fixed magnet is parallel to a central axis of the magnetic member, and the fixed magnet is arranged along the central axis of the magnetic member.

Optionally, the magnetic member is a disc-shaped ring, a central axis of the magnetic member is parallel to a magnetizing direction of the fixed magnet, the magnetizing direction of the magnetic member is directed from one of a first surface of the magnetic member close to the stator and a second surface of the magnetic member close to the impeller to the other surface, and the fixed magnet is disposed along the central axis of the magnetic member.

Optionally, the magnetic member includes a plurality of magnetic blocks, the plurality of magnetic blocks are arranged in a common circle, a central axis of an annular structure surrounded by the plurality of magnetic blocks is parallel to a magnetizing direction of the fixed magnet, the magnetizing direction of each magnetic block is inclined with respect to the magnetizing direction of the fixed magnet, and the fixed magnet is arranged along the central axis of the annular structure.

Optionally, the rotor magnet and the moving magnet are both annular, and a central axis of the rotor magnet and a central axis of the moving magnet are both coincident with a rotating shaft of the impeller; the fixed magnet is cylindrical or annular, the magnetic part is annular, the central axis of the magnetic part coincides with the central axis of the fixed magnet, and the outer diameter of the magnetic part is larger than that of the movable magnet and smaller than the inner diameter of the rotor magnet.

Optionally, the pump casing further has an inflow port and an outflow port communicating with the fluid chamber, a central axis of the outflow port is perpendicular or inclined with respect to a central axis of the inflow port, a position of the fixed magnet corresponds to a position of the inflow port, and a magnetizing direction of the fixed magnet is parallel to the central axis of the inflow port.

Optionally, the pump casing further has a central column disposed in the fluid chamber, the fixed magnet is fixedly accommodated in the central column, a magnetizing direction of the fixed magnet is parallel to a central axis of the central column, the impeller is disposed around the central column and can rotate around the central column, a magnetizing direction of the movable magnet is parallel to a rotating shaft of the impeller, and a magnetizing direction of the magnetic member is parallel to or inclined with respect to the magnetizing direction of the fixed magnet.

Optionally, the rotor magnet and the moving magnet are both disposed on a side of the impeller close to the stator, the rotor magnet and the moving magnet are disposed around a rotation axis of the impeller, respectively, and the rotor magnet and the moving magnet are disposed at an interval in a direction perpendicular to the rotation axis of the impeller.

Optionally, the fixed magnet includes a plurality of magnetic units, the magnetic units are cylindrical or annular, the plurality of magnetic units are all arranged along a central axis of one of the magnetic units, the plurality of magnetic units are coaxial, and magnetizing directions of the plurality of magnetic units are consistent;

and/or the moving magnet comprises a plurality of magnetic ring units, the magnetic ring units are arranged along the rotating shaft of the impeller, and the magnetic ring units are coaxial and have the same magnetizing direction.

Optionally, the pump housing is detachably connected to the driving part, and the magnetic member is fixedly connected to the pump housing or the driving part.

Optionally, the pump casing is made of a non-metallic material.

The application provides a magnetic levitation pump's beneficial effect lies in:

(1) the magnetic suspension pump is characterized in that a magnetic force piece is arranged between an impeller and a stator, a movable magnet and a rotor magnet are fixedly connected to the impeller, a fixed magnet is fixedly connected to a central column, and the impeller can be suspended in a fluid cavity under the combined action of attraction between the stator and the rotor magnet, magnetic action between the movable magnet and the fixed magnet and magnetic action between the magnetic force piece and the movable magnet, so that stable suspension of the impeller is realized. For the blood pump using the separated disposable pump head (including the pump shell and the impeller), compared with the magnetic suspension pump which is provided with a permanent magnet for realizing stable suspension of the impeller on the pump head (such as the pump shell of the pump head), the magnetic suspension pump adopting the mode not only can realize stable suspension of the impeller, but also can conveniently install the magnetic part on the driving part by arranging the magnetic part between the impeller and the stator of the driving part, and can be repeatedly used along with the driving part, so that the parts discarded along with the pump head are reduced, the use cost of the magnetic suspension pump is reduced, the economy is improved, and the resource waste is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a magnetic levitation pump according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the arrangement of the magnetic poles of a fixed magnet, a moving magnet and a magnetic member of the magnetic suspension pump shown in FIG. 1;

FIG. 3 is a schematic diagram of the fixed magnet, the moving magnet, and the magnetic member of the magnetic levitation pump shown in FIG. 2 in a desired stable levitation position;

FIG. 4 is a force diagram of the impeller of the magnetic levitation pump shown in FIG. 2 in the desired stable levitation position shown in FIG. 3;

FIG. 5 is a schematic illustration of the positions of the stationary magnet, the moving magnet and the magnetic member moving axially a distance upward of the impeller of the magnetically suspended pump shown in FIG. 2;

FIG. 6 is a schematic axial force diagram of the impeller shown in FIG. 5 in the position;

FIG. 7 is a schematic diagram showing the positions of the fixed magnet, the moving magnet and the magnetic member, which are axially moved down by a distance, of the impeller of the magnetic suspension pump shown in FIG. 2;

FIG. 8 is a schematic axial force diagram of the impeller shown in FIG. 7 in the position;

FIG. 9 is a schematic radial force diagram of the impeller of the magnetic levitation pump shown in FIG. 2 at a desired stable levitation position;

FIG. 10 is a schematic view of the radial force of the impeller of the magnetic levitation pump shown in FIG. 2 at a position offset from the expected stable levitation position of the impeller shown in FIG. 9;

FIG. 11 is a schematic view of the magnetizing directions of the fixed magnet and the magnetic member of the magnetic suspension pump shown in FIG. 2;

FIG. 12 is a schematic diagram of the magnetic force member of one embodiment of the magnetic suspension pump shown in FIG. 2;

FIG. 13 is a cross-sectional view of the magnetic member shown in FIG. 12, with the direction of the arrows indicating the direction of magnetization of the magnetic member;

FIG. 14 is a schematic diagram of a magnetic force element of another embodiment of the maglev pump shown in FIG. 2;

FIG. 15 is a cross-sectional view of the magnetic member shown in FIG. 14, with the direction of the arrows indicating the direction of magnetization of the magnetic member;

fig. 16 is a partial structural schematic view of another magnetic member of the magnetic suspension pump shown in fig. 2.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, as used herein, refer to an orientation or positional relationship indicated in the drawings that is solely for the purpose of facilitating the description and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The application provides a magnetic levitation pump, and this magnetic levitation pump can be external blood pump, also can be internal blood pump, in particular to centrifugal magnetic levitation pump. It should be noted that the magnetic suspension pump in the embodiment of the present invention may be applied to pumping blood, and may also be applied to pumping other media, which is not limited herein.

As shown in fig. 1, a magnetic levitation pump 10 of an embodiment includes a pump housing 100, a stationary magnet 200, an impeller 300, a moving magnet 400, a rotor magnet 500, a driving part 600, and a magnetic part 700. The impeller 300 is rotatably accommodated in the pump casing 100, the fixed magnet 200 is fixedly connected to the pump casing 100, the moving magnet 400 and the rotor magnet 500 are fixedly connected to the impeller 300, and the driving part 600 can generate a rotating magnetic field for driving the rotor magnet 500 to rotate so as to drive the impeller 300 to rotate; the rotor magnet 500 and the driving part 600 have an attractive force, a first magnetic force action is provided between the moving magnet 400 and the fixed magnet 200, a second magnetic force action is provided between the magnetic member 700 and the moving magnet 400, and the impeller 300 can be suspended under the combined action of the first magnetic force action between the moving magnet 400 and the fixed magnet 200, the attractive force between the rotor magnet 500 and the driving part 600, and the second magnetic force action between the magnetic member 700 and the moving magnet 400.

Herein, the suspension of the impeller 300 referred to in the present application means that the impeller 300 does not contact any position on the pump casing 100.

The pump casing 100 is provided with a fluid chamber 110 and a center post 120 disposed within the fluid chamber 110. The pump casing 100 also has an inflow port 112 and an outflow port 114 communicating with the fluid chamber 110, and the central axis of the outflow port 114 is perpendicular or inclined with respect to the central axis of the inflow port 112. Fluid (e.g., blood, etc.) can enter the fluid chamber 110 through the inlet port 112 and exit through the outlet port 114. The position of the central column 120 corresponds to the position of the inflow port 112. More specifically, the central axis of the center post 120 coincides with the central axis of the inflow port 112.

In the present application, a direction parallel to the central axis of the inflow port 112 is defined as an axial direction of the maglev pump 10, and a direction perpendicular to the central axis of the inflow port 112 is defined as a radial direction of the maglev pump 10. Then, the center post 120 extends in the axial direction of the maglev pump 10, and the outflow port 114 is located in the radial direction of the maglev pump 10.

Specifically, the material of the pump housing 100 may be a biocompatible metal material or a non-metal material, wherein the metal material may be a titanium alloy, and the non-metal material may be a material with better biocompatibility, such as medical polycarbonate PC.

The fixed magnet 200 is disposed in the fluid chamber 110 and is fixed to the pump housing 100. Specifically, the fixed magnet 200 is fixedly received within the central post 120. Specifically, the stationary magnet 200 is a permanent magnet. The magnetizing direction of the fixed magnet 200 is parallel to the central axis of the central column 120, i.e., the magnetizing direction of the fixed magnet 200 is parallel to the axial direction of the magnetic levitation pump 10. The stationary magnet 200 is substantially cylindrical or annular, and the central axis of the stationary magnet 200 coincides with or is parallel to the central axis of the central column 120, and in the present embodiment, the central axis of the stationary magnet 200 coincides with the central axis of the central column 120.

In some embodiments, the stationary magnet 200 may be a complete cylindrical structure or a complete ring structure. In some embodiments, the fixed magnet 200 may also be formed by a plurality of cylindrical or annular magnetic units, the plurality of magnetic units of the fixed magnet 200 are arranged along the central axis of the central pillar 120, and the magnetizing direction of each magnetic unit is the same. It should be noted that the shape of the fixed magnet 200 is not limited to a cylindrical or annular structure, and the shape of the fixed magnet 200 may be designed according to actual needs.

The impeller 300 is disposed in the fluid chamber 110 and surrounds the stationary magnet 200, and the impeller 300 is capable of rotating around the stationary magnet 200. Specifically, when the impeller 300 is rotated in a stable levitation, the rotation axis of the impeller 300 substantially coincides with the central axis of the stationary magnet 200. Specifically in the illustrated embodiment, the impeller 300 is disposed around the center post 120, and the impeller 300 is rotatable about the center post 120. When the impeller 300 is stably rotated, there is a gap between the impeller 300 and the center post 120, i.e., the impeller 300 and the center post 120 are not in contact.

In some embodiments, the impeller 300 is generally annular like in shape, with the axis of rotation of the impeller 300 coinciding with the central axis of the impeller 300. The impeller 300 has a center hole, which is a main flow passage of the impeller 300, and when the impeller 300 is rotated in a stable suspension, the center hole is opposite to the inflow port 112, and a center axis of the center hole of the impeller 300 substantially coincides with a center axis of the inflow port 112.

In some embodiments, the impeller 300 includes a first annular portion, a second annular portion spaced from and opposite to the first annular portion, and a plurality of blades, the first annular portion and the second annular portion are coaxial, the first annular portion is close to the inflow port 112, the plurality of blades are disposed between the first annular portion and the second annular portion, each blade connects the first annular portion and the second annular portion, the plurality of blades are spaced and arranged in a circle, a secondary flow channel is formed between adjacent blades, the secondary flow channel is communicated with the primary flow channel, and fluid flowing into the primary flow channel can flow out from an opening of the primary flow channel far from the inflow port 112 and the secondary flow channel, and the impeller 300 with the structure can reduce damage of the impeller 300 to blood and improve blood compatibility of the blood pump. It is understood that the impeller 300 is not limited to the above-described structure, and in other embodiments, the impeller 300 may not have the first annular portion. The structure of the impeller 300 can be adjusted according to actual needs.

The moving magnet 400 is fixedly connected to the impeller 300, the moving magnet 400 is arranged around the fixed magnet 200, and a first magnetic force is exerted between the moving magnet 400 and the fixed magnet 200. Specifically, the moving magnet 400 is housed in the impeller 300, and more specifically, the moving magnet 400 is housed in the second annular portion of the impeller 300. The moving magnet 400 is disposed around the rotation axis of the impeller 300.

Specifically, the moving magnet 400 is a permanent magnet. The magnetizing direction of the moving magnet 400 is parallel to the rotation axis of the impeller 300. The moving magnet 400 is generally a ring-shaped structure. In some embodiments, the moving magnet 400 may be a whole ring structure, with the central axis of the moving magnet 400 coinciding with the axis of rotation of the impeller 300. In some embodiments, the moving magnet 400 includes a plurality of permanent magnets that are disposed concentrically around the rotation axis of the impeller 300 to form a ring structure, and in this case, adjacent permanent magnets may or may not have a gap therebetween. In some embodiments, the moving magnet 400 includes a plurality of magnetic ring units disposed along the rotation axis of the impeller 300, the plurality of magnetic ring units are coaxial and have the same magnetizing direction.

The rotor magnet 500 is fixedly coupled to the impeller 300. Specifically, the rotor magnet 500 is housed within the impeller 300, and more specifically, the rotor magnet 500 is housed within the second annular portion of the impeller 300. In order to facilitate the assembly of the moving magnet 400, the rotor magnet 500, and the impeller 300, the thickness of the second annular portion is greater than that of the first annular portion along the central axis of the impeller 300, so that accommodating grooves for respectively accommodating the moving magnet 400 and the rotor magnet 500 are provided inside the second annular portion.

Specifically, the rotor magnet 500 is disposed around the rotation axis of the impeller 300, and the rotor magnet 500 and the moving magnet 400 are disposed at a distance in a direction perpendicular to the rotation axis of the impeller 300, that is, the rotor magnet 500 and the moving magnet 400 are disposed at a distance in the radial direction of the maglev pump 10. Wherein the moving magnet 400 is closer to the inner circumferential wall of the impeller 300 than the rotor magnet 500. Specifically, the rotor magnet 500 has a ring shape, the central axis of the rotor magnet 500 coincides with both the rotation axis of the impeller 300 and the central axis of the moving magnet 400, and the inner diameter of the rotor magnet 500 is larger than the outer diameter of the moving magnet 400.

Specifically, the rotor magnet 500 is a halbach array magnet. The rotor magnet 500 includes a plurality of permanent magnets arranged in a ring shape, and a gap may be formed between two adjacent permanent magnets of the rotor magnet 500, or no gap may be formed between the two adjacent permanent magnets.

The drive unit 600 and the impeller 300 are disposed in the axial direction of the maglev pump 10. The driving part 600 includes a stator 610, and the stator 610 is capable of generating a rotating magnetic field that drives the rotor magnet 500 to rotate the impeller 300. Wherein. There is an attractive force between the stator 610 and the rotor magnet 500. The rotor magnet 500 and the moving magnet 400 are both disposed at a side of the impeller 300 adjacent to the stator 610.

Specifically, the stator 610 includes a back iron 612, a plurality of magnetic cores 614, and a coil 616 wound around the plurality of magnetic cores 614, wherein the plurality of magnetic cores 614 are all fixed to the back iron 612 and arranged in a common circle. The plurality of magnetic cores 614 are each opposed to the rotor magnet 500, and an attractive force is provided between the plurality of magnetic cores 614 and the rotor magnet 500. The core 614 is generally cylindrical, the core 614 extends axially, and the back iron 612 is located at one end of the core 614 and is disposed away from the impeller 300. The end of the magnetic core 614 away from the back iron 612 may be provided with the pole piece 618, or the pole piece 618 may not be provided, and the pole piece 618 may improve the magnetic field distribution. It is understood that the stator 610 may also be provided without the back iron 612, and the back iron 612 functions as a closed magnetic circuit to promote and increase the generation of magnetic flux and improve the coupling capability.

Specifically, the driving part 600 is disposed outside the fluid chamber 110. In some embodiments, the driving part 600 further drives the casing 620, the driving casing 620 is detachably connected with the pump casing 100, and the stator 610 is accommodated in the driving casing 620, in this case, the magnetic levitation pump 10 is preferably an in-vitro pump; in some embodiments, the driving shell 620 is fixedly connected to the pump shell 100, for example, the driving shell 620 and the pump shell 100 may be an integrally formed structure, and the stator 610 is accommodated in the driving shell 620, in this case, the magnetic levitation pump 10 may be an in-vitro pump or an in-vivo pump.

Specifically, the driving shell 620 may be made of a biocompatible metal material or a non-metal material, wherein the metal material may be, for example, titanium alloy, and the non-metal material may be a material with better biocompatibility, such as medical polycarbonate PC. If the magnetic suspension pump 10 is an extracorporeal pump, the driving shell 620 and the pump shell 100 are preferably detachably connected, so that the pump head formed by the pump shell 100 and the impeller 300 can be disposable to reduce cross infection caused by repeated use of the pump head, and at this time, the material of the pump shell 100 is preferably a non-metal material to reduce the cost of the magnetic suspension blood pump.

The magnetic member 700 is disposed between the stator 610 and the impeller 300, and a second magnetic force is applied between the magnetic member 700 and the moving magnet 400. Wherein the impeller 300 is capable of being suspended in the fluid chamber 110 by a combined action of the attraction force, the first magnetic force action between the moving magnet 400 and the fixed magnet 200, and the second magnetic force action between the magnetic member 700 and the moving magnet 400. Specifically, when the impeller 300 is rotated in a stable levitation manner, the direction of the moving magnet 400 is substantially parallel to the magnetizing direction of the fixed magnet 200.

Specifically, a first magnetic force between the moving magnet 400 and the fixed magnet 200 is a repulsive force, the first magnetic force is capable of generating a first acting force on the impeller 300, the direction of the first acting force is inclined with respect to the magnetizing direction of the fixed magnet 200, the first acting force has a first component force parallel to the magnetizing direction of the fixed magnet 200, and the direction of the first component force is directed toward or away from the stator 610; the second magnetic force acts to generate at least a force on the impeller 300 directed opposite to the direction of the first component force, wherein the impeller 300 is suspended within the fluid chamber 110 in a direction parallel to the magnetizing direction of the stationary magnet 200 by the combined action of the attraction force between the stator 610 and the rotor magnet 500, the first component force, and the second magnetic force. Since the direction of the first acting force is inclined with respect to the magnetizing direction of the fixed magnet 200, the first acting force has a first component force that is perpendicular to the magnetizing direction of the fixed magnet 200 and perpendicular to the axial direction of the maglev pump 10, or in the radial direction of the maglev pump 10, and the second component force is directed away from the fixed magnet 200, in addition to the first component force that cooperates with the attractive force between the stator 610 and the rotor magnet 500 and the second magnetic force between the magnetic member 700 and the moving magnet 400 to axially levitate the impeller 300, and the second component force can achieve the radial levitation of the impeller 300.

In this embodiment, the magnetizing direction of the fixed magnet 200 is the same as the magnetizing direction of the moving magnet 400, and the magnetic poles on the side where the magnetic member 700 and the moving magnet 400 are close to each other are the same. Referring to fig. 2, for example, in the illustrated embodiment, the magnetic poles on the side where the magnetic member 700 and the moving magnet 400 are close to each other are both N poles, and correspondingly, the side of the fixed magnet 200 close to the stator 610 is N poles. It is understood that in other embodiments, the magnetic poles on the side of the magnetic member 700 and the moving magnet 400 close to each other may be both S-poles, and in this case, the magnetic pole on the side of the fixed magnet 200 close to the stator 610 is S-pole.

Referring to fig. 3, in order to make the first magnetic force between the moving magnet 400 and the fixed magnet 200 act on the impeller 300 to generate a first acting force in a direction inclined with respect to the magnetizing direction of the fixed magnet 200 and make the first acting force have a first component parallel to the magnetizing direction of the fixed magnet 200, an embodiment shown in the figure provides a solution: in the magnetizing direction of the moving magnet 400, the moving magnet 400 has a first pole end 410 and a second pole end 420 facing away from the first pole end 410, and the first pole end 410 is close to the stator 610; in the magnetizing direction of the fixed magnet 200, the fixed magnet 200 has a third magnetic pole end 210 and a fourth magnetic pole end 220 away from the third magnetic pole end 210, the third magnetic pole end 210 is close to the stator 610, wherein the first magnetic pole end 410 of the moving magnet 400 is closer to the stator 610 than the third magnetic pole end 210 of the fixed magnet 200, the magnetic pole of the first magnetic pole end 410 of the moving magnet 400 is the same as the magnetic pole of the third magnetic pole end 210 of the fixed magnet 200, and the magnetic pole of the second magnetic pole end 420 of the moving magnet 400 is the same as the magnetic pole of the fourth magnetic pole end 220 of the fixed magnet 200. During rotation of the impeller 300, the second pole end 420 of the moving magnet 400 is closer to the stator 610 than the fourth pole end 220 of the fixed magnet 200, and the third pole end 210 of the fixed magnet 200 is closer to the stator 610 than the second pole end 420 of the moving magnet 400. Wherein, one side of the magnetic member 700 near the impeller 300 has the same magnetic pole as the first magnetic pole end 410 of the moving magnet 400. At this time, the direction of the first component is a direction toward the stator 610, that is, the direction of the first component is axially downward.

In the illustrated embodiment, the second magnetic force acts as a repulsive force, the magnetizing direction of the magnetic member 700 is inclined with respect to the magnetizing direction of the fixed magnet 200, and the second magnetic force acts on the impeller 300 to generate a force in a direction perpendicular to the magnetizing direction of the fixed magnet 200 and directed toward the fixed magnet 200. That is, the second force generated by the second magnetic force acting on the impeller 300 is inclined upward with respect to the axial direction of the maglev pump 10 and is inclined toward the central axis direction of the fixed magnet 200. In other words, the second magnetic force action can generate a third component force on the impeller 300, which is parallel to the charging direction of the fixed magnet 200 and directed opposite to the direction of the first component force (i.e., the third component force is directed axially upward), and a fourth component force, which is perpendicular to the direction of the third component force and directed toward the direction in which the fixed magnet 200 is located (i.e., the third component force is directed toward the straight line in which the central axis of the fixed magnet 200 is located radially or toward the central column 120).

Then, during the levitation rotation of the impeller 300, the impeller 300 is forced by the first magnetic force between the moving magnet 400 and the fixed magnet 200, the attraction force between the rotor magnet 500 and the stator 610, and the second magnetic force between the moving magnet 400 and the magnetic member 700 as follows, as shown in fig. 4: the attractive force between the stator 610 and the rotor magnet 500 causes the impeller 300 to experience an axially downward force F1; the first magnetic action between the moving magnet 400 and the fixed magnet 200 subjects the impeller 300 to a first force F2 inclined downward with respect to the axial direction, which F2 can be decomposed into a first component F21 inclined downward in the axial direction and a second component F22 in the radial direction; the second magnetic force acts to subject the impeller 300 to a second obliquely upward force F3, F3 which can be resolved into an axially upward third component F31 and a radially fourth component F32.

Assuming that the relative position of the moving magnet 400 and the fixed magnet 200 in fig. 3 is the position of the impeller 300 in the expected stable levitation rotation state, the height difference between the first magnetic-pole end 410 of the moving magnet 400 and the third magnetic-pole end 210 of the fixed magnet 200 in the axial direction is h₀The impeller 300 is brought to a desired position of stable suspension in the axial direction by the combined action of F1, F21 and F31.

Referring to fig. 5 and 6, when the impeller 300 is deviated from the stable levitation position in the axial direction away from the stator 610, the height difference between the first magnetic-pole end 410 of the moving magnet 400 and the third magnetic-pole end 210 of the fixed magnet 200 is h_t1And h is_t1＜h₀The first magnetic force action between the moving magnet 400 and the fixed magnet 200 is reduced, i.e., the component F21 axially downward is smaller to F21'; as the axial distance between rotor magnet 500 and stator 610 increases and the attractive force between stator 610 and rotor magnet 500 decreases, F1 decreases to F1'; magnetic fieldThe distance between the force piece 700 and the movable magnet 400 is increased, the second magnetic force action between the force piece 700 and the movable magnet 400 is reduced, the component force F31 in the axial direction is reduced to F31 ', and at this time, in order to enable the impeller 300 to move axially downwards to return to the position of a stable suspension state, F31' < F21 '+ F1';

referring to fig. 7 and 8, when the impeller 300 is deviated from the stable levitation position in the axial direction toward the stator 610, the height difference between the first pole end 410 of the moving magnet 400 and the third pole end 210 of the fixed magnet 200 is h_t2And h is_t2＞h₀The first magnetic force action between the moving magnet 400 and the fixed magnet 200 increases, i.e., the axially downward component force F21 increases to F21 "; the axial distance between the rotor magnet 500 and the stator 610 decreases, the attractive force between the stator 610 and the rotor magnet 500 increases, and F1 increases to F1 "; the distance between the magnetic member 700 and the moving magnet 400 is reduced, the second magnetic force action between the magnetic member 700 and the moving magnet 400 is increased, and the component force F31 in the axial direction is increased to F31 ″, at which time F31 "> F21" + F1 "is required in order to enable the impeller 300 to move axially upward to return to the position of the stable levitation state.

In one embodiment, in order to realize that F31 ' < F21 ' + F1 ' when the impeller 300 is deviated from the stable levitation position in the direction axially away from the stator 610, and F31 "> F21" + F1 "when the impeller 300 is deviated from the stable levitation position in the direction axially toward the stator 610, then the third component F31 of the second force F3 generated by the second magnetic force between the magnetic member 700 and the moving magnet 400 acting on the impeller 300 may be decreased at a rate greater than the first component F21 of the first force F2 generated by the first magnetic force between the fixed magnet 200 and the moving magnet 400 acting on the impeller 300 when the height difference between the first magnetic pole end 410 of the moving magnet 400 and the third magnetic pole end 210 of the fixed magnet 200 is decreased (i.e., when the impeller 300 is moved axially downward), the third component F31 of the second force F3 generated by the second magnetic force between the magnetic member 700 and the moving magnet 400 acting on the impeller 300 also increases at a rate greater than the first component F21 of the first force F2 generated by the first magnetic force between the fixed magnet 200 and the moving magnet 400 acting on the impeller 300. That is, when the height difference between the first pole end 410 of the moving magnet 400 and the third pole end 210 of the fixed magnet 200 is changed, the rate of change in the magnitude of the second magnetic force action between the magnetic member 700 and the moving magnet 400 is greater than the rate of change in the magnitude of the first magnetic force action between the moving magnet 400 and the fixed magnet 200, and F31 ' < F21 ' + F1 ', F31 "> F21" + F1 "can be realized.

The moving magnet 400 is fixedly connected to the impeller 300, the positions of the fixed magnet 200 and the stator 610 are relatively unchanged all the time, the distance that the moving magnet 400 moves in the axial direction relative to the fixed magnet 200 is equal to the distance that the impeller 300 moves in the axial direction relative to the stator 610, that is, along with the change of the distance between the impeller 300 and the stator 610, the change rate of the magnitude of the second magnetic force action between the magnetic member 700 and the moving magnet 400 is greater than the change rate of the magnitude of the first magnetic force action between the moving magnet 400 and the fixed magnet 200, that is, F31 ' < F21 ' + F1 ', F31 > F21 "+ F1"; more specifically, as the distance between the impeller 300 and the stator 610 changes, the rate of change in the magnitude of the third partial force F31 in the axial direction of the second acting force F3 generated by the action of the second magnetic force between the magnetic member 700 and the moving magnet 400 on the impeller 300 is greater than the rate of change in the magnitude of the first partial force F21 in the axial direction of the first acting force F2 generated by the action of the first magnetic force between the moving magnet 400 and the fixed magnet 200 on the impeller 300, that is, as the distance between the impeller 300 and the stator 610 changes, the rate of change in the magnitude of F31 is greater than the rate of change in the magnitude of F21. The rate of change in the magnitude of F31 may be calculated, for example, such that the difference in height between the first pole end 410 of the moving magnet 400 and the third pole end 210 of the fixed magnet 200 is h_t2The rate of change of the magnitude of F31 is equal to the magnitude of F31' minus the magnitude of F31, and the absolute value of the difference is divided by the magnitude of F31, correspondingly, at a height difference of h_t2The rate of change of the magnitude of F21 is equal to the magnitude of F21 "minus the magnitude of F21, and the absolute value of the difference is divided by the magnitude of F21.

While the rate of change of the magnitude of the second magnetic force between the magnetic member 700 and the moving magnet 400 can be greater than the rate of change of the magnitude of the first magnetic force between the moving magnet 400 and the fixed magnet 200 by adjusting the magnetic densities of the fixed magnet 200 and the magnetic member 700, in one embodiment, the magnetic density of the magnetic member 700 is greater than the magnetic density of the fixed magnet 200.

When the impeller 300 is in the position of the expected stable levitation rotation state in the radial direction, the central axis of the impeller 300 coincides with the central axis of the fixed magnet 200 and the central axis of the magnetic member 700, and at this time, referring to fig. 4 and 9 again, the impeller 300 receives the force components F22 and F32 in the radial direction, and F22 in each direction received by the impeller 300 is equal, and F32 in each direction received by the impeller 300 is equal.

Referring to fig. 10, when the impeller 300 is radially offset from the central axis of the fixed magnet 200, one side of the moving magnet 400 is closer to the fixed magnet 200, the radial force F22 of the fixed magnet 200 received by the moving magnet 400 is increased to F22' on the side of the moving magnet 400 closer to the fixed magnet 200, and the radial repulsive force received by the moving magnet 400 is decreased, i.e., less than F22, on the side of the moving magnet 400 away from the fixed magnet 200, to urge the impeller 300 to automatically return to the center position.

Meanwhile, since the magnetizing direction of the magnetic member 700 is inclined with respect to the axial direction, when the impeller 300 is radially deviated from the central axis of the fixed magnet 200 (i.e., the central axis of the magnetic member 700), the radial repulsive force received in the radial direction at the side of the moving magnet 400 distant from the fixed magnet 200 is increased to F32', and the radial repulsive force received at the side of the moving magnet 400 close to the fixed magnet 200 is reduced to be less than F32; therefore, when the impeller 300 deviates from the center position in the radial direction, the existence of F32' can make the impeller 300 restore to the center position automatically and more quickly, that is, the magnetic force member 700 which is magnetized obliquely relative to the axial direction can accelerate the restoration of the impeller 300, and make the suspension of the impeller 300 in the radial direction more stable and reliable.

The specific magnitude of the first magnetic force between the moving magnet 400 and the fixed magnet 200, the attractive force between the rotor magnet 500 and the stator 610, and the second magnetic force between the moving magnet 400 and the magnetic member 700 may be determined by considering the gravity, the fluid buoyancy, and the like of the impeller 300, the moving magnet 400, and the rotor magnet 500 together according to the actual application, and the relative positions of the moving magnet 400, the fixed magnet 200, and the magnetic member 700, and the magnet magnitude may be determined by selecting the moving magnet 400, the fixed magnet 200, and the magnetic member 700 with appropriate magnetic densities.

In the case of ensuring the clearance between the impeller 300 and the side of the pump case 100 close to the driving part 600 and allowing the interaction, the closer the axial distance between the magnetic member 700 and the moving magnet 400 is, the better, so as to maximize the magnetic force action between the magnetic member 700 and the moving magnet 400.

Specifically, the magnetic member 700 has a substantially ring-shaped configuration, the central axis of the magnetic member 700 coincides with the central axis of the stationary magnet 200, and the outer diameter of the magnetic member 700 is larger than the outer diameter of the moving magnet 400 and smaller than the inner diameter of the rotor magnet 500, so as to reduce the influence of the magnetic member 700 on the interaction between the rotor magnet 500 and the stator 610 and further ensure the magnetic force fit between the magnetic member 700 and the moving magnet 400.

In one embodiment, please refer to fig. 11, the angle α of the inclination of the magnetizing direction of the magnetic member 700 (wherein the line AB with the arrow represents the magnetizing direction of the magnetic member 700) with respect to the magnetizing direction of the fixed magnet 200 (wherein the line CD with the arrow represents the magnetizing direction of the fixed magnet 200) is 10 ° -80 °, so that the second magnetic force action between the magnetic member 700 and the moving magnet 400 can have proper axial component force and radial component force; further, the angle α of the magnetization direction of the magnetic member 700 is 30 ° to 60 ° with respect to the magnetization direction of the fixed magnet 200, so that the second magnetic force action between the magnetic member 700 and the moving magnet 400 can have a large axial component force and, at the same time, a suitable radial component force.

The inclination angle α in the present application refers to an acute angle formed between a straight line in which the magnetization direction of the magnetic member 700 is located and a straight line in which the magnetization direction of the fixed magnet 200 is located.

In some embodiments, as shown in fig. 12 and 13, the magnetic member 700 is a conical ring, the large opening end of the magnetic member 700 faces the impeller 300, and the magnetizing direction of the magnetic member 700 is directed from the outer surface of the conical ring to the inner surface of the conical ring. It is understood that in other embodiments, the magnetic member 700 may be oriented from the inner surface of the conical ring to the outer surface of the conical ring, and in this case, the magnetic pole of the side of the moving magnet 400 close to the magnetic member 700 is only required to be set to be the same as the magnetic pole of the inner surface of the magnetic member 700.

In some embodiments, as shown in fig. 14 and 15, the magnetic member 700 is a disk-shaped ring, and the magnetizing direction of the magnetic member 700 is directed from the surface of the magnetic member 700 near the stator 610 to the surface of the magnetic member 700 near the impeller 300. It is understood that in other embodiments, the magnetizing direction of the magnetic member 700 is directed from the side of the magnetic member 700 close to the impeller 300 to the side of the magnetic member 700 close to the stator 610, and in this case, the magnetic pole of the side of the moving magnet 400 close to the magnetic member 700 is set to be the same as the magnetic pole of the side of the magnetic member 700 close to the impeller 300.

In some embodiments, as shown in fig. 16, the magnetic member 700 includes a plurality of magnetic blocks, the plurality of magnetic blocks are arranged in a common circle, the magnetization direction of each magnetic block is inclined with respect to the magnetization direction of the fixed magnet 200, and the plurality of magnetic blocks form a ring structure, for example, a conical ring structure like that in fig. 12, or a disc-shaped ring structure like that in fig. 14; or, there may be a gap between adjacent magnetic blocks, or there may be no gap.

Specifically, the magnetic member 700 may be mounted on the pump case 100, and may also be mounted on the driving part 600. If the maglev pump 10 is an extracorporeal pump and the pump head (the part including the pump housing 100 and the impeller 300) is disposable, the magnetic member 700 is preferably mounted on the driving part 600, so that the magnetic member 700 can be reused with the driving part 600, thereby reducing the cost of the maglev pump 10 and reducing the waste of resources.

The magnetic suspension pump 10 has at least the following advantages:

(1) the magnetic force member 700 is disposed between the impeller 300 and the stator 610 of the magnetic suspension pump 10, the moving magnet 400 and the rotor magnet 500 are fixedly connected to the impeller 300, the fixed magnet 200 is fixedly connected to the center post 120, an attractive force is provided between the stator 610 and the rotor magnet 500, a first magnetic force action is provided between the moving magnet 400 and the fixed magnet 200, the impeller 300 can be far away from the center post 120 by the first repulsive force, the impeller 300 can be close to the stator 610, a second magnetic force action is provided between the magnetic force member 700 and the moving magnet 400, and the impeller 300 can be suspended in the fluid cavity 110 under the combined action of the attractive force, the first repulsive force and the second repulsive force, so that the suspension of the impeller 300 is realized. For the blood pump using the separated disposable pump head (including the pump housing 100 and the impeller 300), compared with the permanent magnet installed on the pump head (for example, the pump housing 100 of the pump head) for realizing the stable suspension of the impeller 300, the above-mentioned magnetic suspension pump 10 can realize the stable suspension of the impeller 300 by arranging the magnetic member 700 between the impeller 300 and the stator 610 of the driving part 600, and can also conveniently install the magnetic member 700 on the driving part 600 for reuse with the driving part 600, so as to reduce the parts discarded along with the pump head, reduce the use cost of the magnetic suspension pump 10, improve the economy, and reduce the resource waste.

(2) Because the suspension state of the impeller 300 is not the suspension at the constant position, during the rotation of the impeller 300, disturbance to the impeller 300 may be caused due to the change of the rotation speed or the influence of the sudden change of the instant force, so that the impeller 300 deviates from the expected stable suspension position, especially axially, the conventional maglev pump 10 usually adjusts the current of the coil 616 of the stator 610 to compensate the axial force, so as to maintain the axial suspension of the maglev pump 10, however, this way may cause the power consumption of the maglev pump 10 to be larger, and increases the power consumption of the maglev pump 10.

The maglev pump 10 of the present application is designed by the above-described structure, and when the distance between the impeller 300 and the stator 610 changes, the rate of change of the second magnetic force action between the magnetic member 700 and the moving magnet 400 is greater than the rate of change of the first magnetic force action between the moving magnet 400 and the fixed magnet 200, so that when the impeller 300 is about to deviate or has deviated from the stable levitation position in the direction axially away from the stator 610, the resultant force of the axially downward component force of the first magnetic force action and the downward attractive force of the stator 610 to the rotor magnet 500, which the impeller 300 is subjected to, is greater than the axially upward component force of the second magnetic force action to prevent the impeller 300 to be moved upward or to urge the impeller 300 that has moved upward downward, and when the impeller 300 is about to deviate or has deviated from the stable levitation position in the direction axially toward the stator 610, the axially downward component force of the first magnetic force action and the downward attractive force of the stator 610 to the rotor magnet 500, which the impeller 300 is subjected to, are less than the shaft of the second magnetic force action The component force is upward to prevent the impeller 300 to be moved downward or to promote the impeller 300 which has moved downward to move upward, so that the impeller 300 can be suspended more stably even without the axial force compensation of the stator 610 on the impeller 300, and compared with the conventional magnetic suspension pump 10, the suspension of the impeller 300 of the magnetic suspension pump 10 is more stable and reliable, and the power consumption is smaller.

(3) The magnetizing direction of the magnetic member 700 is inclined with respect to the magnetizing direction of the fixed magnet 200, so that the recovery of the impeller 300 in the radial direction can be accelerated, and the suspension of the impeller 300 in the radial direction is more stable and reliable.

It should be noted that the magnetizing direction of the magnetic member 700 is not limited to be inclined with respect to the magnetizing direction of the fixed magnet 200, and in some embodiments, the magnetizing direction of the magnetic member 700 may also be parallel to the magnetizing direction of the fixed magnet 200 and directed away from the stator 610, at this time, the second acting force generated by the second magnetic force acting on the impeller 300 does not have a radial fourth component, and the second acting force is only an axial force, because the radial component of the inclined second acting force on the impeller 300 is to accelerate the recovery of the impeller 300 to quickly return the impeller 300 to the stable position, and the radial component of the first acting force generated by the first magnetic force acting on the impeller 300 between the moving magnet 400 and the fixed magnet 200 can maintain the radial suspension of the impeller 300, and therefore, the magnetizing direction of the magnetic member 700 may also be parallel with respect to the magnetizing direction of the fixed magnet 200.

Then, when the magnetizing direction of the magnetic member 700 is parallel to the magnetizing direction of the fixed magnet 200, in some embodiments, the magnetic member 700 may have a form of a disc or a disc ring, in which the central axis of the magnetic member 700 coincides with the central axis of the fixed magnet 200, and the magnetizing direction of the magnetic member 700 is parallel to the central axis of the magnetic member 700.

In other embodiments, the magnetic member 700 includes a plurality of magnetic blocks disposed around the central axis of the fixed magnet 200, the plurality of magnetic blocks are co-circular, and there may or may not be a gap between adjacent magnetic blocks. At this time, each of the magnetic blocks is magnetized in a direction parallel to the magnetizing direction of the fixed magnet 200.

In addition, in other embodiments, the first force generated by the first magnetic force between the moving magnet 400 and the fixed magnet 200 acting on the impeller 300 may also be directed away from the stator 610, i.e., axially upward, in a direction of the first component parallel to the charging direction of the fixed magnet 200. At this time, in order to make the first acting force have a component force upward in the axial direction, one of the schemes may be: the first pole end 410 of the moving magnet 400 is farther from the stator 610 than the third pole end 210 of the fixed magnet 200, the second pole end 420 of the moving magnet 400 is farther from the stator 610 than the fourth pole end 220 of the fixed magnet 200, and the first pole end 410 of the moving magnet 400 is farther from the stator 610 than the fourth pole end 220 of the fixed magnet 200. Correspondingly, the second magnetic force between the magnetic member 700 and the moving magnet 400 is an attractive force, and then the second magnetic force can generate a second force on the impeller 300 which is axially downward or has a component force axially downward. Due to the scheme, the magnetic member 700 is still arranged between the impeller 300 and the stator 610 of the driving part 600, and the magnetic member 700 can be conveniently installed on the driving part 600 and can be reused with the driving part 600, so that the number of parts discarded along with the pump head is reduced, the use cost of the magnetic suspension pump 10 is reduced, the economy is improved, and the resource waste is reduced.

Alternatively, in other embodiments, the first force generated by the first magnetic force acting on the impeller 300 is still directed away from the stator 610 in the direction of the first component parallel to the magnetizing direction of the fixed magnet 200, i.e. axially upward, and the second magnetic force between the magnetic member 700 and the moving magnet 400 is a repulsive force, so that the second force generated by the second magnetic force acting on the impeller 300 is axially upward or has an axially upward component, and a larger attractive force is required between the stator 610 and the rotor magnet 500 to ensure the axial suspension of the impeller 300. According to the scheme, the magnetic member 700 is still arranged between the impeller 300 and the stator 610 of the driving part 600, and the magnetic member 700 can be conveniently installed on the driving part 600 and can be reused with the driving part 600, so that parts discarded along with the pump head are reduced, the use cost of the magnetic suspension pump 10 is reduced, the economy is improved, and the resource waste is reduced.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above examples only show some embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A magnetic levitation pump, comprising:

a pump housing provided with a fluid chamber;

a rotor magnet fixedly connected to the impeller;

2. A maglev pump according to claim 1, wherein the first magnetic action is a repulsive force capable of generating a first force on the impeller in a direction inclined with respect to a charging direction of the fixed magnet, the first force having a first component force parallel to the charging direction of the fixed magnet, the first component force being directed toward or away from the stator; the second magnetic action is capable of generating at least a force on the impeller directed opposite to the direction of the first force component, wherein the attraction force, the first force component, and the second magnetic action are capable of collectively suspending the impeller in the fluid chamber in a direction parallel to the charging direction of the stationary magnet.

3. A maglev pump according to claim 2, wherein the first component force is directed in a direction in which the stator is located, and a rate of change in magnitude of the second magnetic force action between the magnetic member and the moving magnet is larger than a rate of change in magnitude of the first magnetic force action between the moving magnet and the fixed magnet with a change in distance between the impeller and the stator.

4. A maglev pump according to claim 3, wherein the magnetic density of the magnetic member is greater than the magnetic density of the stationary magnet.

5. A pump as claimed in claim 2, wherein the moving magnet is magnetized in a direction parallel to the rotation axis of the impeller, the fixed magnet is magnetized in a direction identical to that of the moving magnet, and the magnetic pole of the side of the moving magnet close to the magnetic member is the same as that of the magnetic pole of the side of the moving magnet close to the magnetic member.

6. A magnetic suspension pump as claimed in any one of claims 2 to 5, wherein in the charging direction of the moving magnet, the moving magnet has a first pole end and a second pole end facing away from the first pole end, the first pole end being adjacent the stator; in the magnetizing direction of the fixed magnet, the fixed magnet is provided with a third magnetic pole end and a fourth magnetic pole end which is far away from the third magnetic pole end, the third magnetic pole end is close to the stator, the magnetic poles of the third magnetic pole end and the first magnetic pole end are the same, the magnetic poles of the fourth magnetic pole end and the second magnetic pole end are the same, and one side of the magnetic force piece, which is close to the impeller, is provided with the magnetic pole which is the same as the first magnetic pole end of the moving magnet;

7. A pump as claimed in any one of claims 2 to 5, wherein the second magnetic force acts as a repulsive force, the direction of magnetization of the magnetic member is inclined with respect to the direction of magnetization of the fixed magnet, and the second magnetic force acts on the impeller to generate a force in a direction perpendicular to the direction of magnetization of the fixed magnet and directed toward the fixed magnet.

8. A maglev pump according to claim 7, wherein the angle of inclination of the direction of magnetization of the magnetic member with respect to the direction of magnetization of the fixed magnet is 10 ° -80 °.

9. A maglev pump according to claim 8, wherein the angle of inclination of the magnetization direction of the magnetic member with respect to the magnetization direction of the fixed magnet is 30 ° to 60 °.

10. The maglev pump of claim 7, wherein the magnetic member is a conical ring, the large opening end of the magnetic member faces the impeller, the magnetizing direction of the magnetic member is directed from one of the outer surface and the inner surface of the conical ring to the other surface, the magnetizing direction of the fixed magnet is parallel to the central axis of the magnetic member, and the fixed magnet is arranged along the central axis of the magnetic member.

11. A pump as set forth in claim 7, wherein the magnetic member is a disk-shaped ring, a central axis of the magnetic member is parallel to a magnetizing direction of the fixed magnet, the magnetizing direction of the magnetic member is directed from one of a surface of the magnetic member near the stator and a surface of the magnetic member near the impeller toward the other, and the fixed magnet is disposed along the central axis of the magnetic member.

12. The pump of claim 7, wherein the magnetic member comprises a plurality of magnetic blocks, the plurality of magnetic blocks are arranged in a common circle, a central axis of an annular structure formed by the plurality of magnetic blocks is parallel to a magnetizing direction of the fixed magnet, the magnetizing direction of each magnetic block is inclined with respect to the magnetizing direction of the fixed magnet, and the fixed magnet is arranged along the central axis of the annular structure.

13. The pump of any one of claims 1-5, wherein the rotor magnet and the moving magnet are both annular, and the central axis of the rotor magnet and the central axis of the moving magnet are both coincident with the rotation axis of the impeller; the fixed magnet is cylindrical or annular, the magnetic part is annular, the central axis of the magnetic part coincides with the central axis of the fixed magnet, and the outer diameter of the magnetic part is larger than that of the movable magnet and smaller than the inner diameter of the rotor magnet.

14. The pump according to any one of claims 1 to 5, wherein the pump housing further has an inflow port and an outflow port communicating with the fluid chamber, a central axis of the outflow port is perpendicular or inclined with respect to a central axis of the inflow port, a position of the fixed magnet corresponds to a position of the inflow port, and a magnetizing direction of the fixed magnet is parallel to the central axis of the inflow port.

15. The magnetic suspension pump as claimed in any one of claims 1 to 5, wherein the pump casing further has a central column disposed in the fluid chamber, the stationary magnet is fixedly accommodated in the central column, the magnetizing direction of the stationary magnet is parallel to the central axis of the central column, the impeller is disposed around the central column and can rotate around the central column, the magnetizing direction of the moving magnet is parallel to the rotation axis of the impeller, and the magnetizing direction of the magnetic member is parallel to or inclined with respect to the magnetizing direction of the stationary magnet.

16. A pump according to any of claims 1-5, wherein the rotor magnet and the moving magnet are both disposed on a side of the impeller adjacent to the stator, the rotor magnet and the moving magnet are respectively disposed around a rotational axis of the impeller, and the rotor magnet and the moving magnet are disposed at a distance in a direction perpendicular to the rotational axis of the impeller.

17. A magnetic suspension pump as claimed in any one of claims 1 to 5, wherein the fixed magnet comprises a plurality of magnetic units, the magnetic units are cylindrical or annular, the plurality of magnetic units are arranged along the central axis of one of the magnetic units, the plurality of magnetic units are coaxial, and the magnetizing directions are consistent;

18. The pump of claim 1, wherein the pump housing is detachably connected to the driving member, and the magnetic member is fixed to the pump housing or the driving member.

19. The maglev pump of claim 1, wherein the pump housing is made of a non-metallic material.