CN114191703A

CN114191703A - Blood pump with function of actively adjusting guide vanes

Info

Publication number: CN114191703A
Application number: CN202111528114.XA
Authority: CN
Inventors: 常宇
Original assignee: Liwei Huide Wuxi Medical Technology Co ltd
Current assignee: Liwei Huide Wuxi Medical Technology Co ltd
Priority date: 2021-12-14
Filing date: 2021-12-14
Publication date: 2022-03-18

Abstract

The invention relates to a blood pump with the function of actively adjusting guide vanes, which is characterized in that guide vanes and a guide head with actively-variable angles are additionally arranged at the front end of the blood pump, the axis of the cross section of each guide vane can be actively changed according to the actual working condition or the expected working condition of the blood pump, and the included angle formed by the axis and the horizontal plane can be actively changed, so that the blood which vertically flows into the blood pump passes through the guide vanes, a tangential speed which is close to the rotation direction of the blood pump vanes is generated in advance, the tangential speed can be matched with the speed of a current blood pump rotor, the blood speed is increased more gradually while the efficiency of the blood pump is improved, and the impact damage of the centrifugal pump vanes to the blood is reduced. The invention can effectively improve the working efficiency of the blood pump under different working conditions, and simultaneously leads the blood to be stressed uniformly in the process of flowing into the blood pump blades, thereby reducing the damage of the blood pump to the blood.

Description

Blood pump with function of actively adjusting guide vanes

Technical Field

The invention relates to the field of biomedical engineering, in particular to a blood pump which is used for in-vivo or in-vitro life support.

Background

The incidence of cardiovascular diseases is on the rising trend year by year, the mortality rate of heart failure and cardiogenic shock which belong to critical patients is extremely high, and the artificial ventricle auxiliary device (blood pump) has very important clinical value both as a therapeutic measure and as a transitional support of heart transplantation. The blood pump is used as an auxiliary machine for supplying blood, and the blood pump generates pressure difference by means of pneumatics, electromotion or magnetic force to provide auxiliary support for the circulatory system of a human body.

At present, the common blood pump types include axial flow type, centrifugal type and mixed flow type, wherein the centrifugal type blood pump is common, the principle of the centrifugal type blood pump is that blades are arranged on a blood pump rotor, the rotor rotates at a high speed under the driving of a power source, blood in the blood pump is thrown to the outer edge along the blood pump blades, in the process, the blades work on the blood to form pressure difference at an inlet and an outlet of the blood pump, so that the blood is driven to be pumped out in a circulating manner, pressure required by the blood to participate in circulation is provided, the pressure mainly depends on the rotating speed of the blades, and generally, the higher the rotating speed is, the higher the formed pressure is, and the higher the flow speed of the blood is.

At present, the common structure of centrifugal blood pump is the centrifugal blood pump disclosed in chinese patents CN104703637A, 201710804289.6 and 201210274047.8, which adopts a centrifugal blood pump that is light in weight and can provide high torque on the impeller, wherein the impeller is centered axially and radially without any mechanical bearing, which is a typical centrifugal blood pump, although this kind of centrifugal blood pump has unusual expression in hydraulic performance, and can fully meet the use requirement of high pressure difference and high flow rate in use. But certain problems still exist in practical use; when the blades of the impeller with the structure are at high rotating speed, red blood cells in blood can collide to the blades of the blood pump at high speed when entering the blood pump, and the speed on the tangent line is rapidly increased, so that the rapid change greatly increases the damage of the blood, and various complications related to the blood damage can appear after the impeller is used; meanwhile, for a magnetic suspension type centrifugal blood pump, after blood flows into the blood pump, the blood can collide with blades, so that the stability of the blades during high-speed rotation is influenced, and a control system is required to consume extra energy to maintain the stability of a blade rotor; in addition, when the blood flows into the centrifugal blood pump, only the axial speed is available, the tangential speed is not available, and then the rotor blades do work to provide a tangential speed, so that the damage of the blood is greatly increased in the process because the speed changes violently and rapidly. In addition, in the design process of the centrifugal blood pump, the centrifugal blood pump is designed and optimized only aiming at a certain specific working state, and the centrifugal blood pump usually works in a non-rated state due to different patients and different clinical requirements during actual use, so that the power consumption of the blood pump is greatly increased, and the blood is seriously damaged.

Disclosure of Invention

In order to overcome the problems, the invention provides a blood pump with the function of actively adjusting guide vanes. The guide vane and the guide vane rotating shaft are fixed together, the guide vane rotating shaft is connected with the blood pump and the guide head body through the guide vane bearing, the guide vane bearing adopts a bearing with high precision and low rolling resistance, the rotating resistance of the guide vane can be effectively reduced, and one end of the guide vane rotating shaft penetrates through the blood pump shell to be connected with the passive deflection wheel. The active deflecting wheel is divided into an inner layer and an outer layer, the inner layer is fixedly connected with the shell of the blood pump, the outer layer is connected with the passive deflecting wheel, and the outer layer can rotate for a certain angle while keeping the concentricity with the inner layer. The rotation of the driving deflection wheel drives the driven deflection wheel to rotate, and the rotation of the driven deflection wheel drives the guide vanes to deflect by a certain angle. The cross section of the guide vane is a streamline with a certain guide effect, so that blood flowing into the blood pump under the action of the guide vane with a certain angle generates a speed which is the same as the rotation direction of the rotor vane in advance before entering the rotor vane. The deflection angle of the guide vane can be actively adjusted according to the actual working state or the expected working state of the blood pump, so that the blood flowing into the blood pump is correspondingly changed at the increased speed in the tangential direction after flowing through the guide vane, the regulation and control precision of the blood pump can be improved, the change of the speed in the tangential direction of the blood can be more gradual, the efficiency of the blood pump in different working states can be improved, and the damage of the rotor vane to the blood can be correspondingly reduced.

In order to solve the technical problems, the invention adopts a technical scheme that: providing a blood pump with an adaptive flow guide device; the method comprises the following steps: the guide head main body is positioned at the top end of the blood pump blade and does not rotate with the blood pump blade simultaneously when the blood pump works; the guide vane bearing is connected with the blood pump shell and the guide vane rotating shaft and connected with the guide head main body and the guide vane rotating shaft, so that the guide vanes rotate smoothly, and the rotating resistance of the guide vanes is reduced; the guide vane is connected with the guide vane bearing through a guide vane rotating shaft and plays a role in guiding flow; the guide vane rotating shaft penetrates through the whole guide vane and is fixed with the guide vane, the guide vane is driven by the rotation of the guide vane rotating shaft to deflect, one end of the guide vane rotating shaft is connected with the guide head main body, and the other end of the guide vane rotating shaft is connected with the driven deflection wheel; the passive deflection wheel is installed and fixed at one end of the rotating shaft of the guide vane and is attached to the outer layer of the active deflection wheel; the active deflection wheel is positioned on the outer side of the blood pump and is divided into an inner layer and an outer layer, the inner layer is fixed with the shell of the blood pump, the outer layer can rotate while keeping the concentricity with the inner layer, the outer layer of the active deflection wheel rotates to drive the passive deflection wheel to rotate, and the passive deflection wheel drives the guide vanes to deflect by a certain angle.

The guide vanes, the guide vanes at different positions, are deflected simultaneously.

Optionally, the guide vanes at different positions, may be deflected in a group control manner.

Alternatively, each of the guide vanes may be individually controlled to deflect, and the deflection angle may be different.

Optionally, the driving deflection wheel and the driven deflection wheel may be engaged through gears.

Preferably, the outer layer of the active deflection wheel can rotate by an external motor.

The invention has the beneficial effects that: according to different working states and expected working states of the blood pump, the deflection angle of the guide vanes is actively adjusted, so that blood uniformly flows into the blades of the blood pump along the axis of the blood pump, the impact of the blood on the rotor blades of the blood pump is reduced, the generation of turbulence in the rotor blades is reduced, the generation of thrombus and the damage of blood cells are reduced, and the blood compatibility of the blood pump in different working states can be effectively improved; meanwhile, the invention can adaptively increase the tangential speed of blood flowing into the blood pump in advance, effectively improve the working efficiency of the blood pump in different working states and increase the regulation and control precision of the working state of the blood pump.

Drawings

Fig. 1 is a schematic structural view of a blood pump with a flow guide device according to the present invention.

The parts in the drawings are numbered as follows: 1. a guide vane; 2. a guide head main body; 3. blood pump blades; 4. a blood pump inlet; 5. a guide vane bearing; 6. a guide vane shaft; 7. a driving deflection wheel; 8. a passive deflection wheel.

Detailed Description

The following detailed description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings, will make the advantages and features of the invention easier to understand by those skilled in the art, and thus will clearly and clearly define the scope of the invention.

Referring to fig. 1, an embodiment of the present invention: a blood pump with a self-adaptive flow guide device.

As shown in fig. 1, the guide head main body 2 is connected with the blood pump shell through a guide vane rotating shaft 6, wherein 1 is a guide vane, 3 is a rotor blade, 4 is a blood pump inlet, 5 is a guide vane bearing, 6 is a guide vane rotating shaft, 7 is a driving deflection wheel, and 8 is a driven deflection wheel; the guide vane 1 is fixed with a guide vane rotating shaft 6, and one end of the guide vane rotating shaft is fixed with a driven deflection wheel; after passing through a blood pump inlet 4, blood flows into the blood pump and is in contact with a guide head main body 2 and guide vanes 1; the active deflection wheel 7 rotates for a certain angle to drive the passive deflection wheel to rotate, and the rotation of the passive deflection wheel enables the guide vane 1 to rotate for a certain angle; the deflected guide vanes 1 of the blood can generate a tangential speed which is the same as the rotation direction of the rotor vanes 3; the blood then comes into contact with the rotor blades 3 and is accelerated to the same rotational speed as the rotor blades and finally flows out in the tangential direction of the rotor blades. The cross section of the guide vane 1 is in the shape of an axisymmetric water drop, has a certain guide effect, and the projections of different cross section positions along the direction of the central line are equal in size and are overlapped.

In vitro research experiments show that the blood pump with the same rotor blade design can reduce the generation of free hemoglobin and reduce the damage of blood after a flow guide device is added; while the efficiency of the blood pump is increased.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A blood pump with the function of actively adjusting guide vanes; it is characterized by comprising: the guide head main body is positioned at the top end of the blood pump blade and does not rotate with the blood pump blade simultaneously when the blood pump works; the guide vane bearing is connected with the blood pump shell and the guide vane rotating shaft and connected with the guide head main body and the guide vane rotating shaft, so that the guide vanes rotate smoothly, and the rotating resistance of the guide vanes is reduced; the guide vane is connected with the guide vane bearing through a guide vane rotating shaft and plays a role in guiding flow; the guide vane rotating shaft penetrates through the whole guide vane and is fixed with the guide vane, the guide vane is driven by the rotation of the guide vane rotating shaft to deflect, one end of the guide vane rotating shaft is connected with the guide head main body, and the other end of the guide vane rotating shaft is connected with the driven deflection wheel; the passive deflection wheel is installed and fixed at one end of the rotating shaft of the guide vane and is attached to the outer layer of the active deflection wheel; the active deflection wheel is positioned on the outer side of the blood pump and is divided into an inner layer and an outer layer, the inner layer is fixed with the shell of the blood pump, the outer layer can rotate while keeping the concentricity with the inner layer, the outer layer of the active deflection wheel rotates to drive the passive deflection wheel to rotate, and the passive deflection wheel drives the guide vanes to deflect by a certain angle.

2. Guide vane according to claim 1, characterized in that the guide vanes in different positions are deflected simultaneously.

3. Guide vane according to claim 1, characterized in that the guide vanes in different positions can be deflected in groups.

4. Guide vane according to claim 1, characterized in that each guide vane can be individually controlled to deflect and the deflection angle can be different.

5. Active deflection wheel and passive deflection wheel according to claim 1, characterized in that the transmission can be geared.

6. The outer layer of the active deflection wheel of claim 1, wherein the rotation is by an external motor.