Pressurizing unit of impeller assembly, impeller assembly and fluid pumping system

Abstract

The utility model provides a supercharging unit, an impeller assembly and a fluid pumping system, and the supercharging unit is arranged at the downstream of a blade so as to increase the speed of fluid flowing through the blade; the pressurizing unit comprises a near end and a far end, and the radial size of the near end is larger than that of the far end. According to the impeller assembly, the pressurizing unit pressurizes the fluid flowing through the blades, the fluid pumping flow in unit time is increased, and the pumping efficiency of the impeller assembly is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of medical equipment, and in particular to a booster unit of an impeller assembly, an impeller assembly and a fluid pumping system. Background Art

[0002] An interventional ventricular assist device is a medical device that assists in the treatment of high-risk PCI symptoms. The interventional ventricular assist device includes a fluid pumping part, which includes a blood inlet, a blood flow channel, an impeller assembly, and a blood outlet. The impeller assembly is an important component of the fluid pumping device.

[0003] The speed of the fluid after passing through the blades is difficult to meet the design requirements, resulting in insufficient pumping flow and low efficiency of the fluid pumping device. Therefore, how to optimize the design of the impeller assembly to increase the pumping flow is an urgent problem to be solved. Utility Model Content

[0004] In order to overcome at least one of the problems in the related art, the utility model provides a supercharging unit of an impeller assembly in a first aspect, wherein the impeller assembly comprises a rotating shaft, a hub and blades, wherein the rotating shaft is connected to the hub and is used to drive the hub to rotate; the blades are arranged around the outer wall of the hub,

[0005] The booster unit is arranged downstream of the blade in the direction in which the fluid flows through the blade to increase the velocity of the fluid after flowing through the blade;

[0006] The booster unit comprises a proximal end and a distal end, wherein the radial dimension of the proximal end is greater than the radial dimension of the distal end.

[0007] In some optional embodiments, the outer diameter of the boosting unit is less than or equal to the outer diameter of the blade in the compressed state.

[0008] In some optional embodiments, the axial cross-section of the boost unit is a combination of one or more shapes, such as a cone, an arc, or a curve with a gradually changing curvature.

[0009] In some optional embodiments, the inflow angle of the boost unit is an acute angle, and / or the outflow angle of the boost unit is an acute angle.

[0010] The second aspect of the utility model provides an impeller assembly, comprising:

[0011] Axis of rotation;

[0012] Blades, the blades being capable of rotating along with the rotation axis;

[0013] As in any of the boosting units described in the first aspect, the boosting unit is arranged on the rotating shaft.

[0014] In some optional embodiments, the boosting unit is detachably mounted on the rotating shaft.

[0015] In some optional embodiments, the axial direction of the rotating shaft is provided with a hollow structure, and one end is provided with an injection port, and the injection port is connected to the hollow structure;

[0016] A hub, which is at least partially embedded in the hollow structure of the rotating shaft;

[0017] The root of the blade is connected to the hub.

[0018] In some optional embodiments, the outer edge of the blade passes through the rotating shaft and extends outward along the radial direction of the rotating shaft.

[0019] In some optional embodiments, the hollow structure extends along the axial direction of the rotating shaft;

[0020] The side wall of the rotating shaft is also provided with a radial injection hole, and the outer edge of the blade passes through the rotating shaft through the radial injection hole.

[0021] The third aspect of the utility model provides a fluid pumping system, characterized in that:

[0022] It comprises a driving component and an impeller component as described in any one of the second aspects, wherein the driving component drives the impeller component to operate to pump the fluid.

[0023] The technical solution of the utility model has the following advantages or beneficial effects:

[0024] (1) The utility model sets a booster unit downstream of the impeller assembly. After the fluid passes through the blades, it will be affected by the flow guidance of the booster unit. The fluid flow inside the impeller will be closer to the outer edge, which is equivalent to increasing the hub ratio, thereby increasing the pumping flow of the impeller. Therefore, even if the compressed size and / or expanded size of the blades are reduced, although the flow capacity of the blades is reduced, the presence of the booster unit can effectively improve the distribution of flow velocity and pressure in the flow field downstream of the impeller, effectively compensating for the problem of reduced pumping flow caused by reduced flow capacity of the blades.

[0025] (2) The utility model provides geometric shape and dimensional characteristic parameters of the boosting unit, which can effectively utilize the boosting unit to improve the pumping efficiency of the pumping unit while reducing the design difficulty of the boosting unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to better understand the present invention and do not constitute an improper limitation on the present invention.

[0027] Figure 1is a three-dimensional schematic diagram of an impeller assembly according to an embodiment of the utility model;

[0028] Figure 2 is a schematic front view of a rotating shaft according to an embodiment of the utility model;

[0029] Figure 3 is a schematic diagram of a hub and blade assembly according to an embodiment of the utility model;

[0030] Figure 4 is a cross-sectional schematic diagram of a rotating shaft according to an embodiment of the utility model;

[0031] Figure 5 It is a schematic diagram of the inner edge inlet angle and the outer edge inlet angle of the blade according to an embodiment of the utility model;

[0032] Figure 6 It is a schematic diagram of the inner edge outlet angle and the outer edge outlet angle of the blade according to an embodiment of the utility model;

[0033] Figure 7 is a schematic cross-sectional view of a blade in a first position according to an embodiment of the utility model;

[0034] Figure 8 is a schematic cross-sectional view of a blade in a second position according to an embodiment of the utility model;

[0035] Fig. 9 is a schematic diagram comparing the first and second cross-sectional positions of a blade according to an embodiment of the utility model;

[0036] Fig.10 is a schematic diagram of a blade without cross-section according to an embodiment of the utility model;

[0037] Fig.11 is a schematic top view of an impeller assembly according to an embodiment of the utility model;

[0038] Fig.12 It is a schematic diagram of a combination of blades and a hub processed through exhaust holes according to an embodiment of the utility model;

[0039] Fig.13 is a cross-sectional schematic diagram of a rotating shaft provided with exhaust holes according to an embodiment of the utility model;

[0040] Fig.14 It is a schematic diagram of the geometric dimensions of the impeller assembly according to an embodiment of the utility model;

[0041] Fig.15 is a schematic diagram of a first boosting unit according to an embodiment of the utility model;

[0042] Fig.16 is a schematic diagram of a second boosting unit according to an embodiment of the utility model;

[0043] Fig.17 is a schematic diagram of a blade in an expanded state according to an embodiment of the utility model;

[0044] Fig.18 is a schematic diagram of a blade folded state according to an embodiment of the utility model;

[0045] Fig.19 is a schematic diagram of the geometric dimensions of an impeller assembly according to an embodiment of the utility model;

[0046] Fig. 20 is a schematic diagram of flow field distribution of an impeller assembly in a non-pressurized state according to an embodiment of the utility model;

[0047] Fig.21 is a schematic diagram of flow field distribution of an impeller assembly under a pressurized state according to an embodiment of the utility model;

[0048] Fig. 22 is a schematic diagram of an impeller assembly in the prior art. DETAILED DESCRIPTION

[0049] The following is a description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0050] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0051] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0052] As described in the background technology section, in order to overcome at least one of the problems in the related art, the first aspect of the present invention provides an impeller assembly. Figures 1 to 3 As shown, the impeller assembly includes a rotating shaft 101. In some embodiments, the rotating shaft can be a structure of a single diameter, that is, the rotating shaft is a structure of uniform thickness, for example, the outer diameter of the rotating shaft is 0.6-2 mm, preferably 0.8-1.2 mm. A hollow structure is provided inside the rotating shaft. In practice, a material with a certain rigidity, such as metal, etc., can be selected, and a hollow structure can be machined inside it to form the rotating shaft. A hub 301, which is at least partially embedded in the hollow structure of the rotating shaft. In some embodiments, the hub can be fully embedded in the hollow structure. In other embodiments, the hub can also be partially embedded in the hollow structure. A blade 103, the root of the blade is connected to the hub, and the outer edge of the blade extends outward along the radial direction of the rotating shaft after passing through the rotating shaft; wherein the blade is elastic and can be compressed or expanded along the radial direction. Specifically, during the compression process, the blade moves closer to the axial direction of the rotating shaft to reduce the overall outer diameter of the impeller assembly. And the compressed state is maintained for interventional operation. When the target point is reached, the radial constraint force on the blade disappears, and the blade recovers its deformation by its own elasticity and fully unfolds. In contrast, the blades in the related art often need to be subjected to external loads to gradually unfold from a compressed state. Figures 1 to 3 As shown, the hub in the utility model is arranged in the hollow structure inside the rotating shaft, so that the connection part between the blade and the hub is also located inside the rotating shaft, so that the overall outer contour diameter of the impeller with blades of a certain blade height is significantly reduced. That is, the radial dimension from the rotating shaft to the outer edge of the blade can be reduced, so the overall radial dimension of the impeller of the present application can be smaller. The rotating shaft provides a mounting cavity for the hub, and the hollow structure can stably support and protect the hub, so that the hub does not need to have a large radial dimension to provide a stable rotation support force for the blades, and also avoids damage to the hub under the reaction of the impeller. It can be understood that when a material with suitable stiffness and strength is selected to make the rotating shaft, the outer diameter of the rotating shaft can be further reduced, so that the radial dimension of the impeller assembly of the utility model is further compressed.

[0053] like Fig. 22The impeller assembly in the prior art shown (from HeartMate PHP) has a size of 13F in a compressed state and a size of 24F in an expanded state, while the impeller assembly in one embodiment of the present invention has a size of 8F in a compressed state and a size of 22F in an expanded state. It can be clearly seen from the above-mentioned size comparison that the size of the impeller assembly in the embodiment of the present invention is significantly smaller than the minimum size that can be provided by the above-mentioned prior art solutions, whether in a compressed state or an expanded state. In addition, under the same test conditions, the impeller assembly in the HearMate PHP can provide a pumping flow rate of 4L / min, while the corresponding flow rate of the present invention is 5L / min, that is, compared with the prior art, the present invention has a 25% increase in pumping flow rate while significantly reducing the size.

[0054] In some optional embodiments, the hollow structure extends along the axial direction of the rotating shaft; the rotating shaft is also provided with a radial injection hole 201, and the outer edge of the blade passes through the rotating shaft through the radial injection hole. Figure 2-4 In the embodiment shown, the interior of the rotating shaft is drilled to form the hollow structure. The hollow structure can be Figure 4 The blind hole structure shown can also be a through hole structure. Further, in order to facilitate the manufacture of the hub and blades and connect the two with high strength. In some embodiments of the utility model, the hub and blades are processed by an injection molding process. To this end, it is necessary to further set a radial injection hole at the position corresponding to the blade on the rotating shaft. Figure 2 and 4 In the embodiment shown, in the actual processing process, Figure 4 The lower end (or proximal end, injection port) is filled with injection material, and after the injection material flows through the hollow structure, it enters the radial injection hole, flows out radially outward and leaves the rotating shaft, and finally enters the mold for forming the blade. It can be seen that in this embodiment, the hollow structure is connected with the radial injection hole; the hub and the blade are integrally formed by the injection material passing through the hollow structure and the radial injection hole in sequence. This manufacturing process is not only convenient for processing the hub and the blade, but also effectively solves the connection problem between the blade and the hub; more advantageously, the hub is embedded in the rotating shaft, and the blade root of the blade is embedded in the rotating shaft through the radial injection hole, so that the hub and the blade are tightly fitted with the rotating shaft, thereby increasing the connection strength between the hub and the blade and the rotating shaft in the axial and radial directions, effectively limiting the relative displacement between the blade and the rotating shaft during high-speed rotation, and increasing the support effect of the blade root, reducing the deformation of the blade under the reaction force of the fluid during high-speed operation, and improving the fluid pumping performance.

[0055] In some optional embodiments, the hollow structure is a blind hole extending in the axial direction of the rotating shaft; the distance between the distal end of the blind hole and the proximal end face of the rotating shaft is greater than the distance between the distal end of the radial injection hole and the proximal end face of the rotating shaft. Figure 4 In the embodiment shown, the hollow structure inside the rotating shaft extends along its own radial direction and is in the form of a blind hole. The distal end of the blind hole (such as Figure 4 The top of the blind hole shown in FIG. Figure 4 The distance between the bottom end face of the rotating shaft shown in FIG. 1 and FIG. 2 is B. Accordingly, the distal end of the radial injection hole (such as Figure 4 The distance between the top of the radial injection hole shown in the figure and the proximal end face of the rotating shaft is A. Among them, the size of B is larger than A. Preferably, the difference between B and A is greater than 10% of the axial length C0 of the blade. The above-mentioned size relationship between B and A can effectively prevent the elastic blade from moving radially through the radial injection hole, that is, constrain the displacement of the blade and the hub in the radial direction, and increase the connection strength between the hub and the blade and the rotating shaft. In some embodiments, the axial cross-section shape of the hollow structure inside the rotating shaft can be circular, square, etc.

[0056] In some optional embodiments, the inlet angle of the inner edge of the blade is the same as the inlet angle of the radial injection hole; and / or, the outlet angle of the inner edge of the blade is the same as the outlet angle of the radial injection hole. Figures 1 to 2 In the embodiment shown, the fluid passes through the streamlined top of the rotating shaft (i.e. Figure 1 The fluid flows from the right top of the rotating shaft in the impeller to the blade direction, and flows to the downstream booster unit 102 after passing through the blade. Therefore, each inlet angle refers to the angle at which the fluid enters the impeller assembly, and each outlet angle refers to the angle at which the fluid leaves the impeller assembly. Figure 2 and 5As shown, the inner edge inlet angle of the blade is the angle between the tangent of the blade root and the radial direction at the point where the fluid enters the impeller assembly; the inlet angle of the radial injection hole is the angle between the tangent of the inner contour of the blade root corresponding to the radial injection hole at the point where the fluid enters the impeller assembly and the radial direction. In this embodiment, the inner edge inlet angle of the blade is equal to the inlet angle of the radial injection hole, and the two angles are set correspondingly, so the same mark β11 is used to record. Similarly, the inner edge outlet angle of the blade is the angle between the tangent of the blade root and the radial direction at the point where the fluid leaves the impeller assembly; the outlet angle of the radial injection hole is the angle between the tangent of the inner contour of the blade root corresponding to the radial injection hole at the point where the fluid leaves the impeller assembly and the radial direction. In this embodiment, the inner edge outlet angle of the blade is equal to the outlet angle of the radial injection hole, and the two angles are set correspondingly, so the same mark β21 is used to record. Since in this embodiment, the radial injection hole is formed by penetrating the radial outer wall of the rotating shaft in accordance with the shape and curvature of the blade root, the inner edge inlet angle of the blade is equal to the inlet angle of the radial injection hole; and / or, the inner edge outlet angle of the blade is equal to the outlet angle of the radial injection hole, which can match the shape and size of the blade root with the shape and size of the radial injection hole, thereby improving the connection strength between the blade and the rotating shaft. In some optional embodiments, the β11 is between 40° and 80°; and the β21 is between 60° and 90°. The angle range makes the spatial distribution of the blades match the movement direction of the fluid, reduces the resistance of the fluid entering the impeller assembly, and improves the pumping efficiency of the fluid.

[0057] In some optional embodiments, the wheel hub and the rotating shaft are fixedly connected by injection molding, and the two are constrained and limited by shape and size to prevent the wheel hub from moving relative to the rotating shaft. In order to improve the connection strength between the wheel hub and the rotating shaft, in a preferred embodiment, the elastic wheel hub and the rotating shaft are fixed together by injection molding.

[0058] In some optional embodiments, the blades are provided with strength-reinforcing materials. It is understandable that since the blades can switch between folded and unfolded states and can effectively promote the movement of fluids, they need to have both sufficient elasticity and sufficient mechanical strength. To this end, in a preferred embodiment, a material with sufficient elasticity is selected to form the blades by injection molding, and reinforcing materials are added to the blades to ensure that the blades have sufficient mechanical strength. For example, fibers are added. Preferably, the Shore hardness of the elastic molding material used for injection molding is >90A; and the elastic material contains fibers inside, thereby improving the injection molding efficiency and ensuring the strength of the blades.

[0059] The blades in the prior art are difficult to manufacture and their performance is difficult to meet the use requirements, which is also an important technical problem to be solved. Therefore, how to reduce the manufacturing difficulty of the blades and improve their performance and yield rate are the problems to be solved by some embodiments of the utility model.

[0060] To this end, in some optional embodiments of the present invention, the thickness of the blade decreases as the relative blade height increases; and / or the axial length of the blade decreases as the relative blade height increases. Figures 7 to 10 In the embodiment shown, the radial distance between the outer edge of the blade and the outer contour of the rotating shaft is the blade height h. The ratio of the radial distance between the axial section of the blade and the outer contour of the rotating shaft to the blade height h is defined as the relative blade height, as Figure 7 and 8 The h1 and h2 shown in are relative leaf heights. In addition, the thickness of the cylindrical section of the leaf at different relative leaf heights decreases as the relative leaf height increases, such as Figure 7 and 8 The b1 and b2 shown in the figure are both blade thickness. Figures 7 to 10 The comparison shows that h2 b1. That is, the thickness of the blade gradually increases from the top of the blade to the root of the blade. In some embodiments, the thickness of the root of the blade is in the range of 0.2-0.4 mm.<h1>

[0061] Through experimental comparison, it can be found that with the same blade shape, only the blade thickness is changed, and under the same test conditions, the test results shown in Table 1 can be obtained.

[0062] Table 1 Test comparison results of different blade forms

[0063]

[0064]

[0065] Through the above comparison, it can be clearly seen that the scheme of keeping the blade thickness constant is inferior to the scheme of gradually thinning the blade thickness from the inner edge to the outer edge in terms of both the compressed diameter and the deformation under working conditions. It is understandable that the fluid force and centrifugal force on the outer edge of the blade are relatively large. When ensuring the strength of the blade, reasonably reducing the thickness of the outer edge of the blade can not only reduce the deformation of the blade under working conditions and ensure the safety of the impeller assembly, but also effectively reduce the compressed diameter of the blade.

[0066] Correspondingly, the blade length along the axial direction is defined as the blade axial length, and the maximum axial length of the blade in the uncut state is recorded as c0 (e.g. Fig.10 Preferably, the axial length of the blade decreases as the relative blade height increases. Figures 7 to 10 The comparison shows that c0>c2>c1. The above structure and size constraints of the utility model can effectively prevent interference problems or scratches on the blades during the injection molding and demoulding process of the blades.

[0067] In some optional embodiments, the blade wrap angle of the blade is an obtuse angle; and / or the draft angle between the inner edge tangent of the distal end of the blade and the radial normal passing through the inner edge is an acute angle; and / or the draft angle between the inner edge tangent of the proximal end of the blade and the radial normal passing through the inner edge is an acute angle. Fig.11 In the illustrated embodiment, when viewed from above, the wrap angle θ of the blade is an obtuse angle, that is, θ<180°, and preferably, θ is between 90° and 150°. The wrap angle is defined as the angle between the radial normal passing through the inner edge of the blade at the distal end of the blade and the radial normal passing through the inner edge of the blade at the proximal end of the blade. Preferably, the draft angle γ1 between the inner edge tangent of the distal end of the blade and the radial normal passing through the inner edge is an acute angle; preferably, 0°<γ1<30°. In other preferred embodiments, the draft angle γ2 between the inner edge tangent of the proximal end of the blade and the radial normal passing through the inner edge is also an acute angle; preferably, 0°<γ2<30°. The two draft angles being both acute angles can prevent many problems such as interference or scratching of the blade during the injection molding and demolding process of the blade.

[0068] In some optional embodiments, the blade inner edge inlet angle is greater than the blade outer edge inlet angle; and / or the blade inner edge outlet angle is greater than the blade outer edge outlet angle. Figure 5 and 6 As shown, the blade outer edge inlet angle β12 is the angle between the tangent line of the blade outer edge and the radial direction at the point where the fluid enters the impeller assembly; the blade outer edge outlet angle β22 is the angle between the tangent line of the blade outer edge and the radial direction at the point where the fluid leaves the impeller assembly. In some preferred embodiments, the blade outer edge inlet angle is between 30° and 60°, and the blade inner edge inlet angle is between 40° and 80°. In other preferred embodiments, the blade outer edge outlet angle is between 30° and 70°, and the blade inner edge outlet angle is between 60° and 90°.

[0069] In some optional embodiments, at least one exhaust hole is provided at the farthest end of the hollow structure away from the blade, and the exhaust hole is connected to the hollow structure. Fig.12 and 13 In the illustrated embodiment, the hub and the impeller are formed by injection molding a hollow structure of a blind hole structure. When the injection molding material is poured from the proximal end to the distal end of the rotating shaft, and there is a lack of exhaust holes at the distal end of the blind hole, it is difficult for the injection molding material to reach the distal end, resulting in failure of the injection molding process. To this end, in some embodiments of the utility model, at least one exhaust hole 1301 is provided at the farthest end of the hollow structure, that is, at the farthest end away from the blades, and the exhaust hole connects the interior of the hollow structure with the external environment. When the injection molding material enters the hollow structure from the injection port at the proximal end of the rotating shaft, the gas in the hollow structure will be gradually discharged through the exhaust holes, so that the injection molding material smoothly fills the interior of the hollow structure. Fig.12As shown, a protrusion 1201 will be formed correspondingly on the hub formed by injection molding. The radial protrusion 1201 is formed integrally with the hub, which can limit the axial and / or radial displacement of the hub along the rotating shaft, thereby improving the connection strength between the hub and the rotating shaft. In some embodiments, the distance from the outermost side of the free end of the radial protrusion to the axis of the rotating shaft is smaller than the radius of the impeller assembly in the folded state. In other words, since the radial protrusion is manufactured through the exhaust hole, the distance from the outermost end of the exhaust hole to the axis of the rotating shaft is smaller than the radius of the impeller assembly in the compressed state. In other embodiments, a through hole is provided in the hollow structure of the rotating shaft instead of a blind hole. In this case, it is not necessary to provide an exhaust hole, and the exhaust can be directly performed by utilizing the characteristics of the through hole itself.

[0070] In addition, in the prior art, the speed of the fluid after passing through the blades is difficult to meet the design requirements, resulting in insufficient pumping flow and low efficiency of the fluid pumping device. Therefore, how to optimize the design of the impeller assembly to increase the pumping flow is an urgent problem to be solved.

[0071] To this end, in some optional embodiments of the present invention, the impeller assembly further comprises a pressure boosting unit, and the pressure boosting unit is arranged downstream of the blade in the fluid direction. Figure 1 In the embodiments shown in 14 to 16, a booster unit 102 is further provided downstream of the blade. The axial flow surface of the booster unit may be in the shape of an arc (eg Fig.16 As shown, the arc shown in R1) or the diffuse cone (as shown Fig.15 As shown). Preferably, the diffusion cone angle (or inflow angle) α2 of the diffusion cone is an acute angle, for example, its range can be 30° to 80°. In some other embodiments, the outflow angle α3 of the booster unit is also an acute angle, for example, its range can be 30° to 75°. The outer diameter of the booster unit is less than or equal to the outer diameter of the blade in the compressed state; and / or, the closer to the proximal end of the rotating shaft, the larger the outer diameter of the booster unit. Fig.14 As shown, the distal end of the rotating shaft has a streamlined head at an angle of α, and the fluid enters the blade through the distal end and flows to the downstream booster unit. Due to the structural shape and geometric dimensions of the oncoming surface of the booster unit, the fluid passing through this flow surface is accelerated, the fluid dynamic pressure is increased, and it is quickly pumped out from the fluid pumping device.

[0072] like Figures 14 to 18 In the example shown, the booster unit is arranged on the rotating shaft. Preferably, the booster unit is detachably arranged on the rotating shaft. The maximum outer diameter of the booster unit is D3, which is less than or equal to the outer diameter D2 of the blades in the folded state, that is, D3≤D2. Preferably, the axial slope of the flow surface of the booster unit can be conical, arc-shaped or a curve with a gradually changing curvature. When an arc-shaped linear is used, such as Fig.16 As shown, the radius R1 in the form of an arc is calculated according to the following formula:

[0073] (B2 + D3 - D4) / 3.3 < R1 < (B2 + D3 - D4) / 1.6

[0074] Wherein, B2 is the axial length of the pressurizing unit, and B2 < C0 * 0.5; D4 is the diameter of the distal end of the pressurizing unit; D3 is the diameter of the proximal end of the pressurizing unit.

[0075] As Fig.15 and 16 shown in the embodiments, the inflow angle of the pressurizing unit satisfies 0° < α2 < 45°; the outflow angle satisfies 30° < α3 < 75°; wherein, the inflow angle is the angle between the tangent at the inflow of the pressurizing unit and the axis, and the outflow angle is the angle between the tangent at the outflow of the pressurizing unit and the radial direction.

[0076] As Fig.19 shown, the diameter of the impeller hub is D5, and the maximum diameter after the blade is unfolded is D1. The ratio of D4 to D1 is defined as the hub ratio. It can be understood that the smaller the hub ratio, the smaller the relative shaft, the improved flow capacity of the impeller, but the reduced pressurizing effect. Therefore, an appropriate hub ratio is a key parameter for improving the blood pumping performance (such as flow rate, pressure, etc.). However, in order to reduce the folded size of the elastic impeller, it is necessary to reduce the hub diameter, which will affect the blood pumping performance, and the pressurizing unit in the above embodiments just compensates for this problem. As Fig. 20 and 21 shown in the comparison diagrams, when the pressurizing unit is set, the fluid will be affected by the diversion of the pressurizing unit after passing through the blade, and the fluid flow inside the impeller will be closer to the outer edge, which is equivalent to increasing the hub ratio, thereby increasing the pumping flow rate of the impeller.

[0077] The second aspect of the present invention provides a fluid pumping system, and the fluid pumping system includes a driving component and the impeller assembly according to any one of the first aspect. The driving component of the fluid pumping system drives the impeller assembly to operate to pump the fluid. For example, the fluid is transported from the distal end into the fluid pumping system; the fluid entering the fluid pumping system is pressurized by the pressurizing unit and pumped out from the fluid pumping unit with a higher dynamic pressure. Or, at the intervened target position, the fluid flow rate around the ventricular assist device is accelerated, for example.

[0078] The third aspect of the present invention provides a processing method for an impeller assembly, and the processing method is used to process the impeller assembly according to any one of the first aspect. Specifically, the processing method includes:

[0079] First, a hollow structure and a radial injection hole extending in the axial direction are processed in the rotating shaft. The hollow structure and the radial injection hole are connected. The processed hollow structure and radial injection hole are as described above, and the structure diagram is as shown in FIG. Figures 2 to 4 .

[0080] Secondly, injection molding material is injected into the rotating shaft, and the injection molding material is passed through the hollow structure and the radial injection molding holes in sequence; wherein the injection molding material inlet end is opened at the proximal end of the rotating shaft; the injection molding material in the hollow structure part forms the hub, and the injection molding material passing through the radial injection molding holes forms the blades.

[0081] The above-mentioned processing method effectively reduces the processing difficulty of the impeller assembly described in any one of the first aspects and reduces the manufacturing cost.

[0082] In some optional embodiments, the hollow structure is a blind hole extending in the axial direction of the rotating shaft; at least one exhaust hole is processed at the farthest end of the hollow structure away from the blade, wherein the exhaust hole is connected to the hollow structure.

[0083] The fourth aspect of the utility model provides a processing mold for an impeller assembly, and the processing mold is used to process an impeller assembly as described in any one of the first aspects. Specifically, the processing mold includes: a mold body; the rotating shaft is placed in the mold body, and in the rotating shaft, a hollow structure extending along the axial direction is processed from one end of the rotating shaft; and radial injection holes are processed on the side wall of the rotating shaft. In addition, it also includes a blade mold unit, which is arranged on one side of the mold body and is used to inject the blades. The manufacturing method of the utility model effectively reduces the manufacturing difficulty of the impeller assembly and can be mass-produced at low cost.

[0084] In some optional embodiments, when the injection molding material is added to the rotating shaft, the injection molding material is passed through the hollow structure and the radial injection molding holes in sequence; wherein the injection molding material in the hollow structure portion forms the hub, and the injection molding material passing through the radial injection molding holes enters the blade mold unit to form the blades.

[0085] In some optional embodiments, in the processing mold, the hollow structure is a blind hole extending in the axial direction of the rotating axis; at least one exhaust hole is processed at the farthest end of the hollow structure away from the blade, wherein the exhaust hole is connected to the hollow structure.

[0086] The above specific implementation methods do not constitute a limitation on the protection scope of the utility model. After considering the specification and practicing the technical solutions disclosed in this application, those skilled in the art will easily think of other implementation methods of the present disclosure. This application is intended to cover any modification, use or adaptive changes of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary technical means in the technical field that are not disclosed in the present disclosure. The description and examples are to be regarded as exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0087] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A supercharging unit of an impeller assembly, the impeller assembly comprising a rotating shaft, a hub and blades, the rotating shaft being connected to the hub and used to drive the hub to rotate; the blades being arranged around the outer wall of the hub, characterized in that: The booster unit is arranged downstream of the blade in the direction in which the fluid flows through the blade to increase the velocity of the fluid after flowing through the blade; The booster unit comprises a proximal end and a distal end, wherein the radial dimension of the proximal end is greater than the radial dimension of the distal end.

2. The booster unit according to claim 1, characterized in that: The outer diameter of the boost unit is smaller than or equal to the outer diameter of the blade in the compressed state.

3. The booster unit according to claim 1, characterized in that: The axial section of the boost unit is a cone, an arc or a curve with a gradually changing curvature, or a combination of one or more of these.

4. The booster unit according to claim 1, characterized in that: The inflow angle of the boost unit is an acute angle, and / or the outflow angle of the boost unit is an acute angle.

5. An impeller assembly, It is characterized in that include: Axis of rotation; Blades, the blades being capable of rotating along with the rotation axis; The booster unit as described in any one of claims 1 to 4, wherein the booster unit is arranged on the rotating shaft.

6. The impeller assembly according to claim 5, characterized in that: The boosting unit is detachably arranged on the rotating shaft.

7. The impeller assembly according to claim 6, characterized in that: The rotating shaft is provided with a hollow structure in the axial direction, and an injection port is provided at one end, and the injection port is connected with the hollow structure; A hub, which is at least partially embedded in the hollow structure of the rotating shaft; The root of the blade is connected to the hub.

8. The impeller assembly according to claim 7, characterized in that: The outer edge of the blade passes through the rotating shaft and then extends outward along the radial direction of the rotating shaft.

9. The impeller assembly according to claim 8, characterized in that: The hollow structure extends along the axial direction of the rotating shaft; The side wall of the rotating shaft is also provided with a radial injection hole, and the outer edge of the blade passes through the rotating shaft through the radial injection hole.

10. A fluid pumping system, characterized in that: The invention comprises a driving component and an impeller component according to any one of claims 5 to 9, wherein the driving component drives the impeller component to operate so as to pump a fluid.

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