Rotor assembly coaxiality detection tooling

Abstract

The present invention aims to provide a rotor assembly coaxiality detection tool with high measurement accuracy and strong versatility, comprising a fixture for clamping the rotor assembly and a micrometer, the fixture comprising a support and a first rotating shaft and a second rotating shaft that form axial limit and circumferential rotation cooperation with the support, the first rotating shaft and the second rotating shaft being arranged side by side, parallel, and at the same height, the first rotating shaft and the second rotating shaft being provided with multiple groups of detection positions adapted to rotor assemblies of different specifications, the rotor assemblies being placed at the detection positions and forming axial limit and circumferential rotation cooperation. Two adjacent disc groups are processed using the same reference during machining, thereby achieving higher coaxiality, and eliminating the need for adjusting the coaxiality of the chuck and the ejector pin before clamping in traditional detection tooling, thereby improving detection efficiency and achieving higher detection accuracy. Multiple disc groups are spaced apart on the same set of rotating shafts, and the distances between adjacent disc groups are different, so that the coaxiality of rotor assemblies of various specifications can be detected on the same detection tool.

Description

Technical Field

[0001] The present invention relates to the technical field of detection auxiliary tools, and in particular to a coaxiality detection tool for a rotor assembly. Background Art

[0002] A catheter pump can (partially) replace a patient's heart function, providing hemodynamic support for patients with cardiogenic shock or heart failure. After percutaneous implantation, an internal motor drives the impeller, enabling the catheter pump to deliver 2.5-6.0 L / min at a speed of 30,000-50,000 rpm, providing life support for short-term (days or weeks) or long-term (weeks or months) applications. Limited by the inner diameter of blood vessels, the outer diameter of a catheter pump is typically no larger than 7 mm. As a component of the catheter pump motor, the rotor assembly is smaller in size and has a smaller outer diameter.

[0003] As shown in Figure 1, the rotor assembly comprises shaft A and rotor B. The coaxiality between the two is a crucial indicator for ensuring motor performance and preventing vibration and abnormal noise. For catheter pumps, the diameters of shaft A and rotor B are very small. Furthermore, catheter pumps come in a variety of models, each with a different rotor outer diameter and length. The primary challenge addressed by this patent is how to use a single set of tooling to detect the coaxiality of the rotor shafts of various catheter pumps. Summary of the Invention

[0004] The purpose of the present invention is to provide a rotor assembly coaxiality detection tool with high measurement accuracy and strong versatility.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a rotor assembly coaxiality detection tool, including a fixture and a micrometer for clamping the rotor assembly, the end of the measuring head of the micrometer abuts against the surface of the rotor assembly, the fixture includes a support and a first rotating shaft and a second rotating shaft that form axial limit and circumferential rotation cooperation with the support, the first rotating shaft and the second rotating shaft are arranged side by side, parallel, and at the same height, and multiple groups of detection positions suitable for rotor assemblies of different specifications are provided on the first rotating shaft and the second rotating shaft. The rotor assembly is placed at the detection position and forms axial limit and circumferential rotation cooperation.

[0006] The first rotating shaft and the second rotating shaft have the same structure. A plurality of disks are arranged on the shaft body of the first rotating shaft at intervals along its axial direction. The disks are coaxially arranged with the first rotating shaft and have a diameter greater than the diameter of the first rotating shaft. The spacing between adjacent disks is different. The disks at corresponding positions on the first rotating shaft and the second rotating shaft constitute a disk group. The two adjacent disk groups jointly support the rotating shaft of the rotor assembly, and the minimum gap between the disk groups is less than the diameter of the rotating shaft.

[0007] The first rotating shaft and the disc thereon are integrally machine-formed, and the second rotating shaft and the disc thereon are integrally machine-formed.

[0008] The distance between two adjacent disk groups is equal to the rotor length of the corresponding rotor assembly.

[0009] The first rotating shaft and the second rotating shaft protrude from one end of the disc to the outside of the support, and the end is connected to a pulley. The two pulleys form a belt transmission with a handwheel rotatably arranged on the support through a transmission belt, and the handwheel is arranged parallel to the axis core of the pulley.

[0010] The first rotating shaft and the second rotating shaft are made of stainless steel.

[0011] A clamping unit is also provided on the support, and the clamping unit includes a vertical plate, one end of the clamp is hinged to the vertical plate, and the other end protrudes toward the middle of the support, a pressure rod is provided in the socket at the free end of the clamp, one end of the pressure rod is clamped in the clamp, and the other end is provided with a pressure head, and a spring is provided at the hinge shaft. The spring provides elastic force to drive the clamp to rotate and drive the pressure head to press the rotor assembly onto the disc group.

[0012] The pressure rod is located just above the gap between the first rotating shaft and the second rotating shaft. The pressure head is also disc-shaped. When in the pressing position, the pressure rod is arranged parallel to the first rotating shaft, and the pressure head is located in the area between the two disc groups.

[0013] The fixture and the micrometer are both arranged on the base, which is also provided with a guide rail. The length direction of the guide rail is arranged parallel to the first rotating shaft. The slider is sleeved on the guide rail to form a sliding fit. The micrometer is fixedly connected to the slider through a multi-stage flip frame.

[0014] The end of the measuring head of the multimeter is made of flexible material.

[0015] Compared with the prior art, the present invention has at least the following two excellent technical effects:

[0016] 1. The area between adjacent disc groups constitutes the positioning area of rotor B. The two adjacent disc groups are processed based on the same reference, so the coaxiality is higher. It also eliminates the need to adjust the coaxiality of the chuck and the ejector before clamping in traditional inspection tooling, thereby improving inspection efficiency and higher inspection accuracy.

[0017] 2. Multiple disc groups are arranged on the same set of rotating shafts, and the distances between adjacent disc groups are different. Therefore, the coaxiality of rotor assemblies of various specifications can be tested on the same testing tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1a and Figure 1b These are schematic diagrams of the rotor assembly structures of two different specifications;

[0019] Figure 1c is a structural diagram of the rotating shaft;

[0020] Figure 2 、 Figure 3 A three-dimensional diagram of the position detection tooling;

[0021] Figure 4 for Figure 3 Left view of;

[0022] Figure 5 for Figure 3 Right view;

[0023] Figure 6 for Figure 2 main view. DETAILED DESCRIPTION

[0024] It should be noted that the tooling in the present invention can detect the rotating shaft A (such as Figure 1c As shown), the rotor assembly after the shaft A and the rotor B are assembled can be detected (as shown Figure 1a and Figure 1b As shown), the following takes the rotor assembly as an example, combined with Figure 2-Figure 6 The present invention is described in further detail.

[0025] A rotor assembly coaxiality detection tool includes a fixture 10 for clamping the rotor assembly and a micrometer 20. The end of the measuring head 21 of the micrometer 20 abuts against the surface of the rotor assembly. The fixture 10 includes a support 11 and a first rotating shaft 12 and a second rotating shaft 13 that form axial limit and circumferential rotation cooperation with the support 11. The first rotating shaft 12 and the second rotating shaft 13 are arranged side by side, parallel, and at the same height. The first rotating shaft 12 and the second rotating shaft 13 are provided with multiple groups of detection positions suitable for rotor assemblies of different specifications. The rotor assembly is placed at the detection position and forms axial limit and circumferential rotation cooperation. In the above scheme, multiple detection positions are set on the first rotating shaft 12 and the second rotating shaft 13, which can detect rotor assemblies of different specifications, thereby improving the versatility of the entire tooling; secondly, the structure on the same detection position is processed based on the same reference, and the structures on different detection positions are also processed based on the same reference, ensuring the coaxiality of each detection position itself, so the accuracy is high when detecting the coaxiality of the rotor assembly; finally, the rotor assembly is placed at the detection position and constitutes axial limit and circumferential rotation cooperation, that is, the limit structures at both ends of the rotor assembly are set on the rotating shaft. Compared with the traditional detection tooling, which requires adjusting the coaxiality of the chuck and the ejector itself before clamping, and then clamping the rotor assembly, it saves operating steps, improves detection efficiency, and has higher detection accuracy.

[0026] The specific structure of the first rotating shaft 12 and the second rotating shaft 13 is preferably as follows: the first rotating shaft 12 and the second rotating shaft 13 have the same structure, and a plurality of disks a are arranged on the shaft body of the first rotating shaft 12 along its axial direction at intervals. The disks a are coaxially arranged with the first rotating shaft 12 and the diameter of the disks a is larger than the diameter of the first rotating shaft 12. The spacing between adjacent disks a is different. The disks a at corresponding positions on the first rotating shaft 12 and the second rotating shaft 13 constitute a disk group. The two adjacent disk groups jointly support the rotating shaft A of the rotor assembly. The minimum gap between the disk groups is smaller than the diameter of the rotating shaft A, so as to prevent the rotating shaft A from falling from the gap when the rotating shaft A is individually detected.

[0027] Specifically, the area between adjacent disc assemblies forms the positioning area for rotor B. Since two adjacent disc assemblies are machined using the same reference, this results in higher coaxiality and eliminates the need to adjust the coaxiality of the chuck and ejector pin before clamping, as is often the case with traditional inspection tooling. This improves inspection efficiency and accuracy. Multiple disc assemblies are spaced apart on the same rotating shaft, with varying distances between adjacent disc assemblies. This allows the coaxiality of rotor assemblies of various specifications to be inspected using the same inspection tooling.

[0028] As a preferred embodiment of the present invention, the first rotating shaft 12 and the disc a thereon are integrally machined, and the second rotating shaft 13 and the disc a thereon are integrally machined. This allows the first rotating shaft 12 and the disc a thereon to be clamped and positioned only once during machining, ensuring that they are machined with the same axis as the reference, thus ensuring their coaxiality. The second rotating shaft 13 and the disc a thereon are also machined using the same method. A more preferred embodiment is that the first rotating shaft 12 and the second rotating shaft 13 are originally the same rotating shaft, and the disc a is machined first before being cut, further ensuring the concentricity of the two rotating shafts.

[0029] The distance between two adjacent disc groups is equal to the length of the rotor B of the corresponding rotor assembly. Figure 2 As shown, four pairs of disc assemblies with different spacing can form a test position for measuring three different specifications of rotor assemblies. When the rotor assembly is placed in the test position, the rotating shaft A is pressed onto the adjacent disc assemblies, and the rotor B is placed in the gap between the adjacent disc assemblies. The two end faces of the rotor B are respectively in contact with the end faces of the disc assemblies, limiting their axial displacement. Compared with the traditional fixture structure of the chuck and the ejector pin (not only the ejector pin, but also the ejector pin, chuck, etc.), the two adjacent disc assemblies in the present invention are processed based on the same reference during processing, so the coaxiality is higher, and the operation of adjusting the coaxiality of the chuck and the ejector pin before clamping is eliminated, thereby improving detection efficiency and higher detection accuracy. When only the rotating shaft A is tested, since the diameters of each disc a are equal, it can be placed directly on the disc assembly.

[0030] To drive the rotation of first and second rotating shafts 12 and 13, the ends of the first and second rotating shafts 12 and 13, away from the disc a, protrude from the outside of the support 11. These ends are connected to pulleys 14. These pulleys 14 cooperate with a handwheel 16, which is rotatably mounted on the support 11, via a transmission belt 15. The handwheel 16 is arranged parallel to the axis of the pulleys 14. Turning the handwheel 16 causes the two rotating shafts to rotate simultaneously, thereby driving the rotor assembly thereon to rotate.

[0031] Since the rotor B of the rotor assembly is magnetic, if the first rotating shaft 12 and the second rotating shaft 13 are made of ordinary cast iron material, adsorption, tilting and other phenomena will occur when the rotor assembly is placed in the detection position, affecting the detection accuracy and detection efficiency. Therefore, the first rotating shaft 12 and the second rotating shaft 13 here are made of stainless steel. The magnetic rotor assembly does not adsorb to stainless steel, so the rotor assembly can be easily placed in the appropriate position, ensuring the stability of the posture and the high efficiency of the detection.

[0032] In order to prevent the rotor assembly from tilting during rotation, a clamping unit 30 is also provided on the support 11. The clamping unit 30 includes a vertical plate 31, one end of a clamp 32 is hinged to the vertical plate 31, and the other end protrudes toward the middle of the support 11. A pressure rod 33 is provided in the socket at the free end of the clamp 32. The position of the pressure rod 33 in the socket at the free end of the clamp 32 can be adjusted according to the position of the rotor assembly. One end of the pressure rod 33 is clamped in the clamp 32, and the other end is provided with a pressure head 34. A spring (not shown in the figure) is provided at the hinge shaft 35. The spring provides elastic force to drive the clamp 32 to rotate and drive the pressure head 34 to press the rotor assembly against the disc assembly. In the natural state, the elastic force of the spring always drives the pressure head 34 to press the rotor assembly. By slightly applying force with the hand to overcome the elastic force of the spring, the pressure head 34 can be moved away from the rotor assembly, making it easy to take and place the rotor assembly. By this form of lower support and upper pressure, the rotor assembly is stably placed in a defined detection position.

[0033] In order to evenly compress the rotor assembly, the pressure rod 33 is located directly above the gap between the first rotating shaft 12 and the second rotating shaft 13. The pressure head 34 is also disc-shaped, and when in the compression position, the pressure rod 33 is arranged parallel to the first rotating shaft 12, and the pressure head 34 is located in the area between the two disc groups, pressing the middle part of the surface of the rotor B.

[0034] Since the specifications of the rotor assemblies of various types of catheter pumps are different, the positions of the assemblies on the fixture during testing are different. Therefore, the position and angle of the micrometer 20 need to be adjusted so that the end of the measuring head 21 of the micrometer 20 is exactly against the surface of the rotor assembly. The fixture 10 and the micrometer 20 are both set on the base 40. The base 40 is also provided with a guide rail 41. The length direction of the guide rail 41 is arranged parallel to the first rotating shaft 12. The slider 42 is sleeved on the guide rail 41 to form a sliding fit. The micrometer 20 is fixedly connected to the slider 42 through the multi-stage flip frame 22. The slider 42 is moved to drive the micrometer 20 to move along the length direction of the guide rail 41 so that the position of the micrometer corresponds to the position of the rotor assembly. Then, the multi-stage flip frame 22 is adjusted so that the measuring head 21 of the micrometer 20 avoids surrounding obstacles and is perpendicular to the axis of the rotor assembly, thereby improving the accuracy of the measurement.

[0035] Due to the particularity of the catheter pump's operating environment, the motor is exposed to a bloody environment for extended periods. To prevent blood from entering the motor and causing thrombosis, a flushing fluid must be introduced into the gap between the rotor assembly and the stator inside the motor. Both blood and flushing fluid are corrosive media, and corrosion significantly reduces the magnetic properties of the rotor assembly. Furthermore, if the magnet continues to operate even after corrosion, the neodymium iron boron magnet, a sponge of corrosion products, destroys the structure and causes fragments to flake off the magnet surface, degrading the performance of the blood pump using the magnet. Therefore, a corrosion-resistant coating is applied to the motor housing and rotor assembly. To prevent the measuring head 21 from scratching the rotor assembly's surface coating, the end of the measuring head 21 of the micrometer 20 is made of a flexible material. When measuring, gently lift the measuring rod by hand and place the rotor assembly under the measuring rod for measurement. Do not allow the measuring rod to suddenly drop onto the rotor assembly, and do not violently vibrate or strike the indicator.

Claims

1. A rotor assembly coaxiality detection tool, comprising a fixture (10) for clamping the rotor assembly and a micrometer (20), wherein the end of the measuring head (21) of the micrometer (20) abuts against the surface of the rotor assembly, and is characterized in that: The fixture (10) includes a support (11) and a first rotating shaft (12) and a second rotating shaft (13) that form an axial limit and circumferential rotation cooperation with the support (11); the first rotating shaft (12) and the second rotating shaft (13) are arranged side by side, in parallel, and at the same height; the first rotating shaft (12) and the second rotating shaft (13) are provided with a plurality of detection positions adapted to rotor assemblies of different specifications; the rotor assemblies are placed at the detection positions and form an axial limit and circumferential rotation cooperation; The first rotating shaft (12) and the second rotating shaft (13) have the same structure. A plurality of disks (a) are arranged on the shaft of the first rotating shaft (12) at intervals along its axial direction. The disks (a) are coaxially arranged with the first rotating shaft (12) and the diameter of the disks (a) is larger than the diameter of the first rotating shaft (12). The spacings between adjacent disks (a) are different. The disks (a) at corresponding positions on the first rotating shaft (12) and the second rotating shaft (13) constitute a disk group. The two adjacent disk groups jointly support the rotating shaft (A) of the rotor assembly. The area between the adjacent disk groups constitutes the positioning area of the rotor (B). The minimum gap between the disk groups is smaller than the diameter of the rotating shaft (A). The first rotating shaft (12) and the disc (a) thereon are integrally machined and formed, and the second rotating shaft (13) and the disc (a) thereon are integrally machined and formed; The distance between two adjacent disc groups is equal to the length of the rotor (B) of the corresponding rotor assembly.

2. The rotor assembly coaxiality detection tool according to claim 1, characterized in that: The first rotating shaft (12) and the second rotating shaft (13) extend outward from the support (11) at one end away from the disc (a), and are connected to pulleys (14). The two pulleys (14) are coupled to a handwheel (16) rotatably arranged on the support (11) via a transmission belt (15) to form a belt transmission. The handwheel (16) and the shaft core of the pulley (14) are arranged in parallel.

3. The rotor assembly coaxiality detection tool according to claim 1, characterized in that: The first rotating shaft (12) and the second rotating shaft (13) are made of stainless steel.

4. The rotor assembly coaxiality detection tool according to claim 1, characterized in that: A pressing unit (30) is also provided on the support (11), and the pressing unit (30) includes a vertical plate (31), one end of a clamp (32) is hinged to the vertical plate (31), and the other end protrudes toward the middle of the support (11), a pressure rod (33) is provided in the socket of the free end of the clamp (32), one end of the pressure rod (33) is clamped in the clamp (32), and a pressure head (34) is provided at the other end, and a spring is provided at the hinge shaft, and the spring provides elastic force to drive the clamp (32) to rotate and drive the pressure head (34) to press the rotor assembly onto the disc assembly.

5. The rotor assembly coaxiality detection tool according to claim 4, characterized in that: The pressure rod (33) is located directly above the gap between the first rotating shaft (12) and the second rotating shaft (13). The pressure head (34) is also disc-shaped. When in the pressing position, the pressure rod (33) is arranged parallel to the first rotating shaft (12), and the pressure head (34) is located in the area between the two disc groups.

6. The rotor assembly coaxiality detection tool according to claim 1, characterized in that: The fixture (10) and the micrometer (20) are both arranged on a base (40). A guide rail (41) is further provided on the base (40). The length direction of the guide rail (41) is arranged parallel to the first rotating shaft (12). The slider (42) is sleeved on the guide rail (41) to form a sliding fit. The micrometer (20) is fixedly connected to the slider (42) via a multi-stage flip frame (22).

7. The rotor assembly coaxiality detection tool according to claim 6, characterized in that: The end of the measuring head (21) of the micrometer (20) is made of a flexible material.

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