CN101513546A

CN101513546A - Hydrodynamic suspension bearing for artificial heart

Info

Publication number: CN101513546A
Application number: CNA2009100969739A
Authority: CN
Inventors: 阮晓东; 韩青; 邹俊; 林哲; 杨华勇
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2009-03-26
Filing date: 2009-03-26
Publication date: 2009-08-26
Anticipated expiration: 2029-03-26
Also published as: CN101513546B

Abstract

The invention discloses a hydrodynamic suspension bearing for artificial heart. A rotor with arc inner top surface is embedded in a circular groove of stator with arc top, a circular permanent-magnet magnetic steel is arranged on the inner ring of the rotor, a electromagnetic coil is fixed on the outer ring of the stator, the top of the stator is provided with a pitch-variable helical groove, a constant-pitch helical groove is arranged on the outer ring of the stator, an impeller is arranged at the upper top of the stator and in the pump shell, the pump shell is integrated with the stator, the blood flow in from the inlet of the pump shell, most of blood flow out from the outlet of the pump shell by the rotating of the impellor, a small amount of blood form a closed loop in the clearance between the helical grooves of the rotor and the stator, the clearance between the lower surface of stator and the bottom of the rotor and clearance between the inner wall of the rotor and the stator, and is merged with the blood at the inlet. The invention has simple structure, less bearing wearing, small heating amount and power consumption, reduces the energy input of the artificial heart, thus being beneficial for the light and portable artificial heart.

Description

The Hydrodynamic suspension bearing that is used for artificial heart

Technical field

The present invention relates to medical apparatus and instruments, relate in particular to a kind of Hydrodynamic suspension bearing that is used for artificial heart.

Background technology

At present, the bearing that is applied in the artificial heart mainly contains Mechanical Contact formula bearing and non-contact type bearing two big classes.Mechanical Contact formula bearing exists motor bearings wearing and tearing and frictional heating and the problem of bringing out thrombosis, and therefore, non-contact type bearing is the research focus of modern artificial heart.

Non-contact type bearing divides magnetic suspension bearing, Hydrodynamic suspension bearing, hybrid bearing.Magnetic suspension bearing (for example referring to Chinese patent CN200610098332.3) successfully is applied on the artificial heart, but the complexity of magnetic suspension blood pump motor control technology, and need extra energy input, though states such as U.S., day, moral take the lead in being engaged in this technical research for many years, so far still have many technical problems, the equal many places of product are in the trial period.The blended bearing technology of Hydrodynamic suspension and magnetic suspension is by U.S. Arrow International company and Australian HeartWare company successfully in the application product, and entered clinical experimental stage, but still has the control system complicated problems.Because two kinds of suspended patterns of Hydrodynamic suspension and other are compared, need not complicated control and displacement transducer, and need not extra energy expenditure, Hydrodynamic suspension also has advantages such as reliability height, strong shock resistance simultaneously, therefore, the artificial heart of Hydrodynamic suspension technology also begins more to be paid attention to.

There is following problem in (for example referring to Chinese patent CN200610098332.3) for the magnetic suspension bearing technology:

(1) Active Magnetic Suspending Bearing needs the more energy input.

(2) in order to make the magnetic suspension bearing function-stable, need high-precision control structure, thereby increased the complexity of The whole control system.

Summary of the invention

The purpose of this invention is to provide a kind of Hydrodynamic suspension bearing that is used for artificial heart.

For achieving the above object, the technical solution used in the present invention is:

The present invention includes pump case and impeller, rotor, stator, permanent magnetic steel and solenoid.With inner top surface is that to be embedded in the top be in the arcual stator ring groove to arcual rotor, annular permanent magnetic steel is installed on the inner ring of rotor, solenoid is fixed on the outer ring of stator, the stator top has the variable-pitch auger groove, the rotor outer ring has the uniform pitch helicla flute, end face is installed impeller on the rotor, and impeller is installed in the pump case, and pump case and stator link into an integrated entity; Blood flows into from the pump case porch, most of blood flows out from the pump case exit by the rotation of impeller, small part blood is by the helicla flute gap of stator and rotor, the gap of rotor lower surface and stator bottom surface, the gap of rotor inner wall and stator, form the loop of a sealing, converge with the blood of porch.

The beneficial effect that the present invention has is:

Owing to adopted the Hydrodynamic suspension bearing structure, simple in structure, in long-term maintenance bearing performance, can guarantee that bearing wear is few, caloric value is little, and power consumption is little, and avoided the design of complex control system, reduced the energy input of artificial heart, effectively reduced the impost of artificial heart, helped artificial heart and develop to lightness, portable direction.

Description of drawings

Fig. 1 is a structural principle sketch map of the present invention.

Fig. 2 is a blade wheel structure principle schematic of the present invention.

Fig. 3 is the α angle sketch map of Fig. 2 impeller blade.

Fig. 4 is a rotor structure principle schematic of the present invention.

Fig. 5 is the β angle sketch map of Fig. 4 rotor recesses.

Fig. 6 is stator of the present invention and housing parts sketch map.

Among the figure: 1, pump case, 2, impeller, 2A, impeller thin-walled, 2B, impeller heavy wall, 3, rotor, 4, stator, 5, the variable-pitch auger groove, 6, the uniform pitch helicla flute, 7, permanent magnetic steel, 8, solenoid, 9, the pump case outlet, 10, the pump case inlet.

The specific embodiment

Below in conjunction with drawings and Examples, the present invention is further illustrated.

As shown in Figure 1, the present invention includes pump case 1 and impeller 2, rotor 3, stator 4, permanent magnetic steel 7 and solenoid 8; With inner top surface is that to be embedded in the top be in arcual stator 4 annular grooves to arcual rotor 3, annular permanent magnetic steel 7 is installed on the inner ring of rotor 3, solenoid 8 is fixed on the outer ring of stator 4, stator 4 tops have variable-pitch auger groove 5, rotor 3 outer rings have uniform pitch helicla flute 6, end face is installed impeller 2 on the rotor 3, and impeller 2 is installed in the pump case 1, and pump case 1 links into an integrated entity with stator 4; Blood enters the mouth from pump case and 10 flows into, most of blood exports 9 outflows by the rotation of impeller 2 from pump case, small part blood is by the helicla flute gap of stator 4 with rotor 3, the gap of rotor lower surface and stator bottom surface, the gap of rotor inner wall and stator, form the loop of a sealing, converge with the blood of porch.Described impeller 2 and rotor 3, the composition surface between two parts member are the plane, and connected mode adopts pastes or bolted.

As shown in Figures 2 and 3, the blade of described impeller 2, blade are 3～6, and every all becomes big gradually along the thickness on the impeller direction of rotation, and the angle α between impeller thin-walled 2A and the impeller heavy wall 2B is 0.1 °～0.5 °.

As shown in Figure 4 and Figure 5, the bottom surface of described rotor 3 is provided with groove, and the number of groove is identical with the sheet number of blade, and each groove all becomes big gradually along the thickness on the direction of rotation, and the angle β of groove and stator 4 is 0.1 °～0.5 °.

As shown in Figure 4, described rotor 3 outer rings have four-head uniform pitch helicla flute 6, equidistantly open a clockwise uniform pitch helicla flute 6 respectively from rotor end-face.The cross sectional shape of groove is a circular arc.

As shown in Figure 6, the top of described stator 4 has four-head variable-pitch auger groove 5, equidistantly opens a counterclockwise variable-pitch auger groove 5 respectively from stator 4 upper surfaces, and variable-pitch auger groove 5 begins to be varying pitch from stator 4 tops.The cross sectional shape of groove is a rectangle.

Operation principle of the present invention is as follows:

Population structure when Fig. 1 has represented that the Hydrodynamic suspension bearing of embodiment of the present invention is applied in the artificial heart, when switching in the solenoid 8, impeller 2 can rotate by transfer 3 under the action of alternating magnetic field that alternating current produces together, the blood major parts that flowed into by pump case inlet 10 export 9 with certain speed from pump case and pump under the effect of impeller 2, when rotor 3 along the circumferential direction moves with certain speed, owing to can form low pressure in the center of impeller 2, go out to form high pressure in pump case outlet 9, therefore, under pressure reduction and action of centrifugal force, small part blood can be in the helicla flute gap of stator 4 with rotor 3, the gap of rotor lower surface and stator bottom surface, the gap of rotor inner wall and stator, form a mobile loop, the blood that makes blood form secondary back and porch from this runner converges, and flows out together from pump case outlet 9.Between impeller 2 and pump case 1, can produce the thrust liquid film between rotor 3 lower surfaces and stator 4 bottom surfaces, impeller 2 and rotor 3 are played the axial support effect, thereby form axial Hydrodynamic suspension bearing; Producing radially liquid film between equidistant helicla flute 6 in rotor 3 outer rings and the stator 4 and between rotor 3 inner rings and the stator 4, rotor 3 is played the radial support effect, thereby form radially Hydrodynamic suspension bearing.Wherein, the effect of variable-pitch auger groove 5 and uniform pitch helicla flute 6 is: in rotor 3 rotating process, blood more helps the formation of axial thrust Hydrodynamic suspension bearing along the bottom and the gathering of the uniform pitch helicla flute 6 arrival rotors of rotor 3 peripheries; Simultaneously, between the variable-pitch auger groove 5 and rotor 2 at stator 4 tops, the blood of secondary back is assembled at this place, more helps forming axial Hydrodynamic suspension bearing, plays the effect of axial suspension bearing equally.Therefore, whole impeller 2 and rotor 3 are in a kind of dynamic balancing of continuous variation.

Claims

1. a Hydrodynamic suspension bearing that is used for artificial heart is characterized in that: comprise pump case (1) and impeller (2), rotor (3), stator (4), permanent magnetic steel (7) and solenoid (8); With inner top surface is that to be embedded in the top be in arcual stator (4) annular groove to arcual rotor (3), annular permanent magnetic steel (7) is installed on the inner ring of rotor (3), solenoid (8) is fixed on the outer ring of stator (4), stator (4) top has variable-pitch auger groove (5), rotor (3) outer ring has uniform pitch helicla flute (6), rotor (3) is gone up end face impeller (2) is installed, and impeller (2) is installed in the pump case (1), and pump case (1) links into an integrated entity with stator (4); Blood flows into from pump case inlet (10), most of blood flows out from pump case outlet (9) by the rotation of impeller (2), small part blood is by the helicla flute gap of stator (4) with rotor (3), the gap of rotor lower surface and stator bottom surface, the gap of rotor inner wall and stator, form the loop of a sealing, converge with the blood of porch.

2. a kind of Hydrodynamic suspension bearing that is used for artificial heart according to claim 1, it is characterized in that: the blade of described impeller (2), blade is 3～6, every all becomes big gradually along the thickness on the impeller direction of rotation, and the angle α between impeller thin-walled (2A) and the impeller heavy wall (2B) is 0.1 °～0.5 °.

3. a kind of Hydrodynamic suspension bearing that is used for artificial heart according to claim 1, it is characterized in that: the bottom surface of described rotor (3) is provided with groove, the number of groove is identical with the sheet number of blade, each groove all becomes big gradually along the thickness on the direction of rotation, and the angle β of groove and stator (4) is 0.1 °～0.5 °.

4. a kind of Hydrodynamic suspension bearing that is used for artificial heart according to claim 1 is characterized in that: described rotor (3) outer ring has four-head uniform pitch helicla flute (6), equidistantly opens a clockwise uniform pitch helicla flute (6) respectively from rotor end-face.

5. a kind of Hydrodynamic suspension bearing that is used for artificial heart according to claim 1, it is characterized in that: the top of described stator (4) has four-head variable-pitch auger groove (5), equidistantly open a counterclockwise variable-pitch auger groove (5) respectively from stator (4) upper surface, variable-pitch auger groove (5) begins to be varying pitch from stator (4) top.