Hydrodynamic bearing for blood pump

Abstract

The utility model discloses a hydrodynamic bearing for a blood pump, the hydrodynamic bearing is sleeved on a main shaft, a plurality of first grooves and second grooves are arranged on the inner surface of the hydrodynamic bearing around the circumference, and the first grooves and the second grooves are arranged at intervals and have different depths; each of the first groove and the second groove comprises a first groove section and a second groove section, the first end of the first groove section is communicated with the first end of the second groove section, and the communication point is positioned in front of the rotating direction of the main shaft; the second end of the first groove section and the second end of the second groove section are located behind the rotation of the main shaft and extend in the direction away from the other groove section. And the two groove sections are used for guiding lubricating oil to the middle position of the dynamic pressure bearing. The groove structure improves the lubrication friction characteristic of the bearing and improves the performance of the artificial heart blood pump.

Description

Technical Field

[0001] The utility model relates to the technical field of cardiac assist devices, in particular to an interventional artificial cardiac blood pump device. Background Art

[0002] A pVAD is an artificial heart that uses a small blood pump to be inserted into the ventricle percutaneously to maintain the patient's blood circulation. It is usually used in emergency situations, such as short-term cardiac support during and after surgery for high-risk coronary artery intervention patients and patients with cardiogenic shock. The blood pump motor usually includes a hydrodynamic bearing that plays a supporting role.

[0003] At present, the technical research of pVAD in China is usually based on the products that have been put on the market, and most companies focus on the performance of ultra-micro motors. In the newer research in China, the structural design of hydrodynamic bearings is basically similar to that of products put on the market abroad. The V-shaped grooves on the inner diameter surface of the existing hydrodynamic bearings are all of a single depth, and the benefits of the structural design vary. Utility Model Content

[0004] The purpose of the utility model is to solve the above problems and provide a liquid hydrodynamic bearing for a blood pump. By designing a hydrodynamic bearing structure with multi-depth V-shaped grooves, the lubrication and friction characteristics of the bearing are improved, thereby improving the performance of the blood pump motor.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A liquid hydrodynamic bearing for a blood pump, which is sleeved on a main shaft, and the inner surface of the hydrodynamic bearing is arranged around the circumference with a plurality of first grooves and second grooves, the first grooves and the second grooves are arranged at intervals and have different depths; the first groove and the second groove each include a first groove segment and a second groove segment, one end of the first groove segment is connected to one end of the second groove segment, and the connection point is located in front of the main shaft rotation direction; the other end of the first groove segment and the other end of the second groove segment are located behind the main shaft rotation, and extend in a direction away from the other respectively; the two groove segments are used to guide lubricating oil to the middle position of the hydrodynamic bearing.

[0007] In a possible embodiment, the second end of the first groove section and the second end of the second groove section respectively pass through the upper and lower ends of the hydrodynamic bearing.

[0008] In a possible embodiment, the depth of the first groove is 10 um, and the depth of the second groove is 15 um.

[0009] In a possible embodiment, the depth of the first groove is 15 um, and the depth of the second groove is 10 um.

[0010] In a possible embodiment, the width of the first groove and the second groove is 15 um.

[0011] In a possible embodiment, the first slot section and the second slot section are arranged at an angle ranging from 90° to 120°.

[0012] In a possible embodiment, the gap between the hydrodynamic bearing and the main shaft is 8um~12um.

[0013] In a possible embodiment, the first grooves and the second grooves are alternately and evenly spaced within a range of 1 / 2 to 3 / 4 of the circumference of the inner surface of the hydrodynamic bearing.

[0014] In a possible embodiment, the hydrodynamic bearing is made of ceramic material.

[0015] The beneficial effects of the utility model are as follows: a plurality of grooves are provided on the inner diameter surface of the hydrodynamic bearing, and the grooves have two different depths in the radial direction of the hydrodynamic bearing; there are multiple grooves of each depth, and the grooves of the two different depths are evenly and alternately distributed along the same circumferential direction, which is beneficial to improving the lubrication and friction characteristics of the bearing and improving the performance of the artificial heart blood pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front view of the hydrodynamic bearing of the artificial blood pump of the utility model.

[0017] Figure 2 It is a schematic diagram of the grooves on the inner diameter surface of the bearing of the utility model.

[0018] Figure 3 It is a schematic diagram of the depth of multiple V-shaped grooves of the bearing of the utility model.

[0019] In the figure: 1, hydrodynamic bearing; 2, main shaft; 3, first groove; 4, second groove; 31, first groove section; 32, second groove section. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the technical solution of the utility model, the utility model is described in detail below in conjunction with the accompanying drawings. The description in this part is only exemplary and explanatory and should not have any limiting effect on the protection scope of the utility model.

[0021] Please refer to Figure 1-3As shown, a liquid hydrodynamic bearing for a blood pump is sleeved on a main shaft 2, and a plurality of first grooves 3 and second grooves 4 are arranged around the circumference of the inner surface of the hydrodynamic bearing 1, and the first grooves 3 and the second grooves 4 are arranged at intervals and have different depths; the first grooves 3 and the second grooves 4 both include a first groove section 31 and a second groove section 32, and one end of the first groove section 31 is connected to one end of the second groove section 32, and the connection point is located in front of the rotation direction of the main shaft 2; the other end of the first groove section 31 and the other end of the second groove section 32 are located behind the rotation of the main shaft, and extend in a direction away from the other respectively; the two groove sections are used to guide the lubricating oil to the middle position of the hydrodynamic bearing 1.

[0022] When the main shaft rotates, the lubricating oil will flow along the first groove 3 and the second groove 4. Because pressure is generated between the main shaft 2 and the hydrodynamic bearing 1, the 5% glucose heparin solution pushes the main shaft away from the inner surface of the bearing, so that the main shaft 2 will not directly contact the hydrodynamic bearing 1.

[0023] Furthermore, the depth of the first groove 3 and the second groove 4 and the rotation speed of the main shaft 2 will affect the pressure and friction generated between the shaft and the hydrodynamic bearing 1, thereby affecting the lubrication and friction effect. Therefore, the present embodiment uses two different depths of the first groove 3 and the second groove 4 to effectively improve the lubrication and friction characteristics of the hydrodynamic bearing 1. Because large and shallow textures can reduce friction under full film lubrication, and small and deep textures are effective under mixed lubrication and boundary lubrication, it is proposed to combine small and deep textures with large and shallow textures, so that all textures can effectively reduce friction under low contact pressure. When the motor drives the main shaft 2 to rotate, the hydrodynamic bearing 1 is accompanied by multiple lubrication processes such as hydrodynamic lubrication, boundary lubrication, and mixed lubrication. The hydrodynamic bearing 1 with multi-depth grooves can optimize different lubrication states at the same time.

[0024] In some possible embodiments, the gap between the hydrodynamic bearing 1 and the main shaft 2 is 10 um.

[0025] In some possible embodiments, one end of the main shaft 1 is connected to a motor, and the motor is used to drive the main shaft to rotate. Optionally, the motor can be an ultra-micro hollow cup motor.

[0026] In some possible embodiments, the first grooves 3 and the second grooves 4 are alternately arranged in a range of 1 / 2 to 3 / 4 on the circumference of the inner surface of the hydrodynamic bearing 1. The range of 1 / 2 to 3 / 4 may include a pressure-increasing area and a pressure-reducing area.

[0027] In some possible embodiments, the first slot section 31 and the second slot section 32 are arranged at an angle ranging from 90° to 120°. Figure 2 The angle between C and D is 120 degrees.

[0028] Optionally, the depth of the first groove 3 is 15 um, the depth of the second groove 4 is 10 um, and the groove width is 15 um. Figure 3 shown.

[0029] Optionally, the depth of the first groove 3 is 10 um, the depth of the second groove 4 is 15 um, and the groove width is 15 um.

[0030] In some embodiments, the hydrodynamic bearing 1 is made of high-performance engineering ceramic material. Ceramic material has high hardness, wear resistance, low friction coefficient and good thermal stability, and can maintain a long service life under high-speed rotation.

[0031] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0032] This article uses specific examples to illustrate the principles and implementation methods of the utility model. The above examples are only used to help understand the method and core ideas of the utility model. The above is only a preferred implementation method of the utility model. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the utility model, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the utility model to other occasions without improvement, should be regarded as the protection scope of the utility model.

Claims

1. A liquid dynamic pressure bearing for a blood pump, which is sleeved on a main shaft, characterized in that: The inner surface of the hydrodynamic bearing is circumferentially arranged with a plurality of first grooves and second grooves, the first grooves and the second grooves are spaced apart and have different depths; the first grooves and the second grooves each include a first groove segment and a second groove segment, the first end of the first groove segment is connected to the first end of the second groove segment, and the connection point is located in front of the main shaft rotation direction; the second end of the first groove segment and the second end of the second groove segment are located behind the main shaft rotation, and extend in a direction away from the other respectively; the two groove segments are used to guide the lubricating oil to the middle position of the hydrodynamic bearing.

2. A liquid dynamic bearing for a blood pump according to claim 1, characterized in that: The second ends of the first groove section and the second groove section respectively penetrate the upper and lower ends of the hydrodynamic bearing.

3. The liquid dynamic bearing for a blood pump according to claim 1, characterized in that: The depth of the first groove is 10 um, and the depth of the second groove is 15 um.

4. The liquid dynamic bearing for a blood pump according to claim 1, characterized in that: The depth of the first groove is 15 um, and the depth of the second groove is 10 um.

5. A liquid dynamic bearing for a blood pump according to claim 3 or 4, characterized in that: The width of the first groove and the second groove are both 15 um.

6. The liquid dynamic bearing for a blood pump according to claim 1, characterized in that: The first slot section and the second slot section are arranged at an angle, and the angle ranges from 90° to 120°.

7. The liquid dynamic bearing for a blood pump according to claim 1, characterized in that: The first grooves and the second grooves are alternately and evenly arranged in a range of 1 / 2 to 3 / 4 of the circumference of the inner surface of the hydrodynamic bearing.

8. The liquid dynamic bearing for a blood pump according to claim 1, characterized in that: A gap is left between the hydrodynamic bearing and the main shaft, and the gap ranges from 8um to 12um.

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