RU210144U1 - DISC PUMP OF LEFT VENTRICULAR BYPASS TO SUPPORT MECHANICAL HEART WORK - Google Patents

Abstract

The claimed utility model relates to medicine, to artificial implantable organs, such as pumps for pumping biological fluids, in particular blood. The purpose of the claimed utility model is to achieve such a technical result as improving the reliability of the disk pump by reducing the formation of stagnant and turbulent blood flow zones. This goal is achieved as follows: a left ventricular bypass disk pump to maintain the mechanical work of the heart, containing a hollow body equipped with nozzles for inlet and outlet flows, stators with windings and a rotor with parallel disks and permanent magnets, united by a magnetic circuit, where the disks are fastened to each other by fixing elements , while the stators are fixed on the housing symmetrically relative to each other, the rotor is placed in the cavity of the housing, and the stator windings and permanent magnets of the rotor are located with an inclination to the plane of the disks, characterized in that the outlet flow pipe has a spiral shape and is located in a plane perpendicular to the axis of the input branch pipe, and the locking elements in the section have a teardrop shape. The inventive pump can be widely used in modern cardiology. It is manufactured at specialized enterprises based on scientific and technical centers.

Description

The claimed utility model relates to medicine, to artificial implantable organs, such as pumps for pumping biological fluids, in particular blood.

Obviously, one of the most important organs for the functioning of the human body is the heart. Therefore, various diseases of this organ are among the necessary research in the field of health. Depending on the disease, medical or surgical therapy can be prescribed, up to partial and complete mechanical replacement of the heart. Unfortunately, despite the fact that the work of the heart is currently well studied, there is no sufficiently high-quality artificial implant that performs cardiac function. So, the main problems of known devices are low productivity, high traumatism of blood cells, low reliability and durability of implanted devices.

For example, a pump used for pumping blood is known (patent US 10166318, published on 01/01/2019), using a rotor suspended by blood flow and the magnetic field of the stator.

A disadvantage of the known pump for pumping blood is the low reliability of operation, due to the formation of stagnant zones, as well as zones of turbulence in the blood flow.

The closest is a disk pump (RF patent 2716100, published on 03/05/2020), containing a hollow body equipped with inlet and outlet pipes, a stator with windings and a rotor with parallel disks and permanent magnets, where the disks are fastened to each other by a fixing element; in this case, the stator is fixed on the housing, and the rotor is placed in the cavity of the housing. The pump additionally contains a second stator with windings, located symmetrically with respect to the plane of the discs, and the rotor consists of two parts, which are also symmetrical with respect to the plane of the discs; in this case, the stator windings and permanent magnets of the rotor are located with an inclination to the plane of the disks.

However, the known design also does not exclude the formation of stagnant zones, as well as the occurrence of turbulence in the flow, and, accordingly, has a low reliability of operation.

The purpose of the claimed utility model is to eliminate the identified drawback to achieve the following technical result: improving the reliability of the disk pump, by reducing the formation of stagnant and turbulent blood flow zones.

This goal is achieved as follows: a left ventricular bypass disc pump to maintain the mechanical work of the heart, containing a hollow body equipped with nozzles for inlet and outlet flows, stators with windings and a rotor with parallel disks and permanent magnets, united by a magnetic circuit, where the disks are fastened to each other by fixing elements , while the stators are fixed on the housing symmetrically with respect to each other, the rotor is placed in the cavity of the housing, and the stator windings and permanent magnets of the rotor are located with an inclination to the plane of the disks, characterized in that the outlet flow pipe has a spiral shape and is located in a plane perpendicular to the axis of the input branch pipe, and the locking elements in the section have a teardrop shape.

A disk pump can in particular be characterized in that the drop-shaped locking elements are curved along the housing.

A disk pump can be characterized in particular by the fact that the outlet flow nozzle has a circular cross section.

A disk pump may in particular be characterized by the fact that the outlet flow pipe has an oval cross section.

The disk pump can be characterized in particular by the fact that the helical shape of the outlet flow pipe is made in the form of an Archimedean spiral section mating with the pump housing.

On FIG. 1 schematically shows the design of the pump, in longitudinal section, in Fig. 2 conventionally shows a cross-section, in the plane of the pump rotor discs, in Fig. 3 conditionally shows the pump, appearance; where the numbers indicate the following:

1. Housing;

2. Branch pipe of an entrance stream;

3. Outlet pipe;

4. Stator;

5. Stator windings;

6. Permanent magnets;

7. Magnetic core;

8. Rotor discs;

9. Rotor;

10. Dividing sleeves;

11. Fixing elements;

12. Power supply and control output.

Presented in the figures disc pump left ventricular bypass to maintain the mechanical work of the heart is arranged as follows.

The hollow body (1) contains an inlet flow pipe (2) and an outlet flow pipe (3). On the body, above and below, there are stators (4), which are inductors with windings (5). The rotor (9) is located inside the housing and is a set of flat disks (8) connected by common fixing elements (11). Discs have a central hole. The discs are separated from each other by means of dividing bushings (10) mounted on the fixing elements (11). The rotor contains a top and a base fixed on it by means of fixing elements (11), in the recesses, in which permanent magnets (6) are fixed, united by a common magnetic circuit (7), located so that their surface plane is parallel to the corresponding stators. The permanent magnets themselves, placed in the recesses of the base and top of the rotor, are located at an angle to the plane of the surface of the rotor discs.

Evaluation of the effectiveness of the pump design is determined by the absence of stagnant zones, turbulent flows, high shear stresses, as well as the creation of the necessary blood flow and the necessary pressure at the pump outlet. Considering that blood is a liquid with a complex rheology, much attention is paid to the issues of blood flow in the mechanical design of the pump. At the development and design stage, much attention is paid to the issues of blood flow in the design of the pump. When pumping through the pump in separate fragmentary parts of the pump, the blood may show signs of laminar or turbulent flow. In laminar flow, blood moves between layers of flow without mixing. With a turbulent flow, the blood begins to experience, as it moves, a rotational motion relative to the direction vector, in which swirling areas or so-called fractal zones are formed.

In the case of designing a pump for pumping blood, a turbulent flow is extremely undesirable, since its appearance in separate fragmentary parts of the pump leads to the destruction of blood cells and an increase in the hemolysis index, as a result of the destruction of the erythrocyte membrane. These factors lead to the risks of thrombosis in the human cardiovascular system. For design purposes, the pump design is subjected to hydrodynamic computer simulation and actual study on hydrodynamic stands simulating the systemic circulation.

In the case of a pump design with a straight outlet pipe (for example, RU 2716100), turbulent flow eddies are observed at the pump outlet. In order to eliminate and reduce turbulent flows, a spiral shape of the outlet pipe was chosen. According to the results of hydrodynamic studies of blood flow in the problem area of the branch pipe, a significant reduction in turbulent flow was achieved. In this case, the shape of the outlet pipe section may be in the form of an Archimedes spiral, mated with the pump casing. This form of spiral provides the most uniform flow of pumped blood. Thus, the most optimal ratio of the dimensions of the outlet pipe is provided, in order to ensure a reduction in the turbulence of the turbulence of the outgoing blood flow. The branch pipe of the outlet flow in cross section can have a round or oval shape, which also eliminates the formation of stagnant and turbulent places.

Also, in order to ensure the reliability of the functioning of the pump, which consists in ensuring a uniform flow of blood fluid, the fixing elements of the disks are made teardrop-shaped in the form of a cut. This shape minimizes the formation of turbulent eddies that occur directly behind the fixing elements when moving in a fluid flow. The blood collides with the rounded shape of the element and begins to go around it, while moving along the surface, which flattens out, turning into a sharp point towards the end. There is no hit in the discharged area, due to this, a uniform blood flow is maintained. For the greatest efficiency and reliability of blood pumping, due to the geometric features of the pump housing structure, such as a cylindrical inner surface, teardrop-shaped elements can be bent along the housing. The surface plane of the fixing element, throughout the flattening, is concave on one side and convex on the opposite side. Thus, it is possible to reduce the turbulence of the flow, when the locking elements move along the radius.

Also, the absence of turbulence phenomena and the presence of stagnant zones have a positive effect on the reliability of the structure. Since, for example, in the presence of stagnant zones, there are high risks of thrombosis, which will introduce additional obstacles to blood flow, a cavitation effect may occur, which, in turn, can destroy the high-precision mechanics of the functioning of an auxiliary heart pump. Thus, the durability and reliability of the device may be reduced. Also, the turbulence of the fluid flow is capable of causing mechanical damage to the internal components of the disc pump during the service life. Eliminating or reducing the likelihood of these processes, increases the reliability and durability of the pump as a whole.

Presented in the figures disc pump left ventricular bypass to maintain the mechanical work of the heart operates as follows.

Given the specifics of the pump as an aid for pumping blood, it is surgically implanted in the patient's chest, facilitating his blood circulation. After connecting the stator windings to the power supply (not shown in the figures), a magnetic field arises through the power supply and control leads (12), which, interacting with the permanent magnets of the rotor, causes the rotor to repel from the inner walls of the housing, creating the effect of rotor levitation. In this case, the blood flow that occurs when entering the inlet flow pipe, entering the internal cavity of the pump, interacts with the rotor disks and, due to the centrifugal force that occurs, is directed to the outlet flow pipe. Due to the shape of which, as well as the shape of the fixing elements, there is a lack of stagnant zones and zones of laminar and turbulent flow.

The inlet of the prototype is connected through a cannula to the apex of the left ventricle, the outlet to the aorta. Conventionally, the pump takes over the systolic and diastolic function of the left ventricle. During the operation of the prototype, the left ventricle through the pump carries out a “conditional ejection” of blood into the aorta, from which the systemic circulation begins. In most clinical cases, the left ventricle in acute heart failure is not able to perform systolic and diastolic function, and when a circulatory assist device is connected, it acts as an intermediate reservoir.

If we trace the blood flow further through the cardiovascular system, then after passing through the systemic circulation, the blood flows into the right atrium through the superior and inferior vena cava, from the right atrium the blood enters the right ventricle, the right ventricle ejects blood into the pulmonary trunk, from which the small the circle of blood circulation, having passed through the small circle, oxygen-enriched blood flows into the left atrium through four pulmonary veins, from the left atrium the blood again enters the left ventricle.

Thus, the use of the inventive disk pump of a left ventricular bypass to maintain the mechanical work of the heart, a spiral outlet, as well as drop-shaped fixing elements, allows achieving the claimed technical result, namely, increasing the reliability of the disk pump, by reducing the formation of stagnant and turbulent areas of blood flow.

Industrial applicability.

The inventive pump can be widely used in modern cardiology. It is manufactured at specialized enterprises based on scientific and technical centers.

Claims (3)

1. A disk pump containing a hollow body equipped with inlet and outlet pipes, stators with windings and a rotor with parallel disks and permanent magnets, united by a magnetic circuit, while the disks are fastened to each other by locking elements, the stators are fixed to the body symmetrically, the rotor is placed in body cavity, and the stator windings and permanent magnets of the rotor are inclined to the plane of the disks, characterized in that the outlet flow pipe is made in the form of a section of the Archimedean spiral conjugated with the body and is perpendicular to the inlet pipe, and the fixing elements have a drop-shaped shape, bent along a cylindrical inner surface of the body along the blood flow and are made concave on one side and convex on the opposite side. 2. Disc pump according to claim. 1, characterized in that the outlet pipe has a circular cross section. 3. Disc pump po. 1, characterized in that the outlet pipe has an oval cross section.

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