Turbo molecular pump magnetic bearing dynamic performance testing device for simulating gas loading

Abstract

The invention relates to the technical field of turbo molecular pump magnetic bearing dynamic performance testing, in particular to a gas loading simulation turbo molecular pump magnetic bearing dynamic performance testing device which comprises a frame, an upper three-axis moving platform is arranged on the top of the frame, and a side three-axis moving platform is arranged on one side of the frame. The upper three-axis moving platform and the side three-axis moving platform are respectively and fixedly connected with a pressure applying assembly, the pressure applying assembly is detachably connected with a simulation rotor, the simulation rotor is detachably connected with a bottom plate, the bottom plate is fixedly connected to the bottom of the frame, and one side of the top surface of the frame is fixedly connected with a visual detection assembly. Axial force and radial force are applied to the molecular pump through the upper three-axis moving platform and the side three-axis moving platform respectively, moments in different directions are applied, and the static and dynamic load performance of the molecular pump under different axial force, radial force and moment combinations can be measured.

Description

Technical Field

[0001] The invention relates to the technical field of dynamic performance testing of a turbomolecular pump magnetic bearing, in particular to a dynamic performance testing device for a turbomolecular pump magnetic bearing with simulated gas loading. Background Art

[0002] The molecular pump is a vacuum obtaining device. Its working principle is that the linear speed of the blades reaches the thermal motion speed of the molecules through high-speed rotation, and the gas obtains a directional speed through momentum exchange with the blades to discharge the cavity; the magnetic levitation turbomolecular pump is used in various industries because of its advantages such as oil-free, wear-free, low noise and can be installed at any angle. The magnetic bearing is a key component of the magnetic levitation turbomolecular pump. It is divided into axial magnetic bearings and radial magnetic bearings, which provide axial force and radial force to suspend the rotor respectively. Its stability is related to the normal operation of the molecular pump. When the load exceeds the load that the magnetic bearing can bear, the rotor loses stability and falls at a very high speed, causing serious harm. When the molecular pump is running, when the gas valve is suddenly opened or the gas flow suddenly increases, the rotor will receive a huge impact load. When the flow is too large, the impact load and torque of the impeller will increase, all of which may cause the load to exceed the limit load borne by the magnetic bearing. Therefore, it is very important to measure the load bearing limit of the magnetic bearing of the molecular pump.

[0003] The performance of the magnetic bearing is different when the rotor is stationary and when the rotor is running at high speed. Its static load limit and dynamic load limit must be tested separately.

[0004] The current static test method for the performance of magnetic bearings of magnetic suspension molecular pumps is to first suspend the rotating shaft of the magnetic suspension bearing in the axial and radial directions, then apply forces in the axial and radial directions, and calculate the static load limit according to the magnitude of the forces. The method for testing the dynamic load performance of molecular pumps is to increase the magnetic bearing with the turbine rotor to the rated speed, and to calculate the dynamic load limit of the magnetic suspension bearing by instantly opening the gas valve to impact the high-speed turbine rotor or gradually increasing the gas flow rate.

[0005] However, when using the above method to test, the equipment conditions and steps required for the dynamic performance test method are much more complicated than those for the static performance test. In addition, when testing dynamic performance, the molecular pump is very likely to become unstable and cause damage to the impeller, which increases the economic cost. At the same time, the force cannot be accurately applied during the test, resulting in a large error in the ultimate load.

[0006] Therefore, there is an urgent need for a dynamic performance test device for turbomolecular pump magnetic bearings that simulates gas loading, which can simultaneously measure the static and dynamic load limits of the magnetic bearings, effectively reduce the complexity and economic cost of the test, and accurately apply the load force. Summary of the invention

[0007] The purpose of the present invention is to provide a device for testing the dynamic performance of a turbomolecular pump magnetic bearing with simulated gas loading, so as to solve the problems existing in the above-mentioned prior art.

[0008] To achieve the above-mentioned purpose, the present invention provides the following scheme: a dynamic performance testing device for a turbomolecular pump magnetic bearing with simulated gas loading, comprising a frame, an upper three-axis moving platform is arranged on the top of the frame, a side three-axis moving platform is arranged on one side of the frame, the upper three-axis moving platform and the side three-axis moving platform are respectively fixedly connected with a pressure applying component, the pressure applying component is detachably connected with a simulated rotor, the simulated rotor is detachably connected with a bottom plate, the bottom plate is fixedly connected to the bottom of the frame, and a visual detection component is fixedly connected to one side of the top surface of the frame.

[0009] Preferably, the pressure applying assembly includes a shell, in which a pressure sensor is installed, the pressure sensor abuts one end of a pressure spring, the other end of the pressure spring abuts a ball, the ball is rotatably connected to a probe housing, the probe housing is fixedly connected and communicated with the shell, and the pressure spring is arranged in the probe housing.

[0010] Preferably, the ball bearing is arranged in an end of the probe housing away from the housing.

[0011] Preferably, the diameter of the ball is not less than the inner diameter of the probe housing.

[0012] Preferably, the upper three-axis mobile platform includes a first X-axis mobile part that is symmetrically arranged, two of the first X-axis mobile parts are fixedly connected to the top of the frame, a first Y-axis mobile part is fixedly connected between the moving ends of the two first X-axis mobile parts, a first Z-axis mobile part is fixedly connected to the moving end of the first Y-axis mobile part, and the moving end of the first Z-axis mobile part is fixedly connected to one of the shells.

[0013] Preferably, the side three-axis mobile platform includes a symmetrically arranged second Z-axis mobile part, two of the second Z-axis mobile parts are fixedly connected to the side walls of the frame, a second X-axis mobile part is fixedly connected between the moving ends of the two second Z-axis mobile parts, a second Y-axis mobile part is fixedly connected to the moving end of the second X-axis mobile part, and the moving end of the second Y-axis mobile part is fixedly connected to the other shell.

[0014] Preferably, the visual detection component includes a second support fixedly connected to the top crossbeam of the frame, and a camera is fixedly connected to the bottom of the second support.

[0015] Preferably, the camera is arranged at an angle and is parallel to a plane formed by the two shells.

[0016] Preferably, adjacent support rods of the frame are respectively fixedly connected with reinforcing ribs, and the reinforcing ribs are arranged obliquely.

[0017] The present invention discloses the following technical effects:

[0018] The present invention adopts a simulated rotor to replace a real turbine rotor, so that when testing dynamic performance, the molecular pump can be directly increased to the rated speed in the air without a pump housing and after being completely sealed, thereby improving the economy during testing; at the same time, the present invention applies axial force and radial force to the molecular pump respectively, and applies moments in different directions through an upper three-axis mobile platform and a side three-axis mobile platform, so that the static and dynamic load performance of the molecular pump under different axial force, radial force and moment combinations can be measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of the three-axis mobile platform of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of the three-axis mobile platform of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of the pressure applying component of the present invention;

[0024] Figure 5 It is a schematic diagram of the structure of the visual detection component of the present invention;

[0025] Among them, 1. frame; 2. upper three-axis moving platform; 3. side three-axis moving platform; 4. pressure applying component; 5. visual detection component; 6. simulated rotor; 11. reinforcing ribs; 12. bottom plate; 21. first X-axis moving part; 22. first Y-axis moving part; 23. first Z-axis moving part; 31. second X-axis moving part; 32. second Y-axis moving part; 33. second Z-axis moving part; 41. shell; 42. pressure sensor; 43. probe housing; 44. pressure spring; 45. ball; 51. second support; 52. camera. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Reference Figure 1-Figure 5 The present invention provides a dynamic performance test device for a turbomolecular pump magnetic bearing with simulated gas loading, comprising a frame 1, an upper three-axis moving platform 2 is arranged on the top of the frame 1, a side three-axis moving platform 3 is arranged on one side of the frame 1, the upper three-axis moving platform 2 and the side three-axis moving platform 3 are respectively fixedly connected with a pressure applying component 4, the pressure applying component 4 is detachably connected with a simulated rotor 6, the simulated rotor 6 is detachably connected with a bottom plate 12, the bottom plate 12 is fixedly connected to the bottom of the frame 1, and a visual detection component 5 is fixedly connected to one side of the top surface of the frame 1.

[0029] The present invention adopts a simulated rotor 6 to replace a real turbine rotor, so that when testing dynamic performance, the molecular pump can be directly increased to the rated speed in the air without a pump housing and after being completely sealed, thereby improving the economy during testing; at the same time, the present invention applies axial force and radial force to the molecular pump respectively, and applies moments in different directions through the upper three-axis mobile platform 2 and the side three-axis mobile platform 3, so that the static and dynamic load performance of the molecular pump under different axial force, radial force and moment combinations can be measured.

[0030] A further optimized solution is that the pressure applying component 4 includes a shell 41, a pressure sensor 42 is installed in the shell 41, the pressure sensor 42 abuts against one end of a pressure spring 44, the other end of the pressure spring 44 abuts against a ball 45, the ball 45 is rotatably connected to a probe housing 43, the probe housing 43 is fixedly connected and communicated with the shell 41, and the pressure spring 44 is arranged in the probe housing 43.

[0031] In a further optimized solution, the ball 45 is arranged in an end of the probe housing 43 away from the housing 41 .

[0032] In a further optimized solution, the diameter of the ball 45 is not less than the inner diameter of the probe housing 43. This prevents the ball 45 from escaping from the probe housing 43 during operation, so that the ball 45 can rotate together with the simulated rotor 6 running at high speed.

[0033] A further optimized solution is that the upper three-axis mobile platform 2 includes a symmetrically arranged first X-axis mobile part 21, the two first X-axis mobile parts 21 are fixedly connected to the top of the frame 1, a first Y-axis mobile part 22 is fixedly connected between the mobile ends of the two first X-axis mobile parts 21, the mobile end of the first Y-axis mobile part 22 is fixedly connected to the first Z-axis mobile part 23, and the mobile end of the first Z-axis mobile part 23 is fixedly connected to a shell 41.

[0034] A further optimized solution is that the side three-axis mobile platform 3 includes a symmetrically arranged second Z-axis mobile part 33, the two second Z-axis mobile parts 33 are fixedly connected to the side wall of the frame 1, a second X-axis mobile part 31 is fixedly connected between the moving ends of the two second Z-axis mobile parts 33, the moving end of the second X-axis mobile part 31 is fixedly connected to the second Y-axis mobile part 32, and the moving end of the second Y-axis mobile part 32 is fixedly connected to another shell 41.

[0035] The first X-axis moving part 21 , the first Y-axis moving part 22 , the first Z-axis moving part 23 , the second X-axis moving part 31 , the second Y-axis moving part 32 , and the second Z-axis moving part 33 use ball screws and are driven by stepping motors respectively.

[0036] According to a further optimized solution, the visual detection component 5 includes a second support 51 fixedly connected to the top crossbeam of the frame 1 , and a camera 52 is fixedly connected to the bottom of the second support 51 .

[0037] In a further optimized solution, the camera 52 is tilted and parallel to the plane formed by the two housings 41. That is, the viewing angle plane of the camera 52 is parallel to the plane formed by the two pressure sensors 42.

[0038] According to a further optimization scheme, adjacent support rods of the frame 1 are respectively fixedly connected with reinforcing ribs 11, and the reinforcing ribs 11 are arranged obliquely. The reinforcing ribs 11 enable the frame 1 to be stably supported.

[0039] At the same time, the positions of the two pressure applying components 4 can be accurately detected by the visual detection component 5, and the load force can be accurately applied at different positions.

[0040] Through the first X-axis moving part 21, the first Y-axis moving part 22, the first Z-axis moving part 23, the second X-axis moving part 31, the second Y-axis moving part 32, and the second Z-axis moving part 33, the two pressure applying components 4 can realize free movement in the three directions of X, Y, and Z respectively, and can be positioned to any position of the axial section and radial section of the simulated turbine. The pressure applying component 4 can apply axial force and radial force to the simulated turbine, and the applied position can be adjusted at the same time, and the equivalent torque can also be applied; at the same time, the visual detection component 5 can detect the position applied by the pressure applying component 4 and feed it back to the computer, so that the operator can adjust the position of the applied load on the computer.

[0041] Working process: Place the molecular pump of the specified model to be tested on the test bench, match the rotating shaft of the molecular pump with the simulated turbine, and remove the molecular pump casing to facilitate the application of load force; first test its static load-bearing performance, control the molecular pump magnetic bearing, suspend the shaft and do not rotate, then control the upper three-axis mobile platform 2 and the side three-axis mobile platform 3 to drive the pressure application component 4 at the end to apply force, and apply force at different positions according to the detection of the visual detection component 5; secondly, measure its dynamic load-bearing performance, increase the molecular pump to the rated speed, and after the molecular pump is stable, control the upper three-axis mobile platform 2 and the side three-axis mobile platform 3 to drive the pressure application component 4 at the end to apply force, and apply force at different positions according to the detection of the visual detection component 5.

[0042] The present invention adopts a simulated turbine to replace the real turbine rotor. The mass and moment of inertia of the simulated turbine are the same as those of the turbine rotor. Since the turbine rotor has multi-stage blades, it cannot be increased to the rated speed in the atmosphere, but the simulated turbine does not have blades and can be increased to the rated speed. In addition, the processing cost of the turbine rotor is extremely high. The simulated turbine is used to reduce the economic losses caused by possible damage to the turbine rotor during testing.

[0043] The present invention measures the dynamic performance and static performance of the magnetic suspension bearing in the same way, solving a series of problems such as the inability to apply static test devices and methods to dynamic testing, the high complexity of dynamic test devices and the need for higher economic costs, and the low accuracy of the applied force.

[0044] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0045] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A dynamic performance test device for a turbomolecular pump magnetic bearing with simulated gas loading, characterized in that: The invention comprises a frame (1), wherein an upper three-axis movable platform (2) is arranged on the top of the frame (1), and a side three-axis movable platform (3) is arranged on one side of the frame (1); the upper three-axis movable platform (2) and the side three-axis movable platform (3) are respectively fixedly connected with a pressure applying component (4); the pressure applying component (4) is detachably connected with a simulation rotor (6); the simulation rotor (6) is detachably connected with a bottom plate (12); the bottom plate (12) is fixedly connected to the bottom of the frame (1); and a visual detection component (5) is fixedly connected to one side of the top surface of the frame (1).

2. The dynamic performance test device for turbomolecular pump magnetic bearings loaded with simulated gas according to claim 1, characterized in that: The pressure applying assembly (4) comprises a shell (41), a pressure sensor (42) is installed in the shell (41), the pressure sensor (42) is abutted against one end of a pressure spring (44), the other end of the pressure spring (44) is abutted against a ball (45), the ball (45) is rotatably connected to a probe housing (43), the probe housing (43) is fixedly connected to and communicates with the shell (41), and the pressure spring (44) is arranged in the probe housing (43).

3. The dynamic performance test device for turbomolecular pump magnetic bearings loaded with simulated gas according to claim 2, characterized in that: The ball (45) is arranged in an end of the probe housing (43) away from the casing (41).

4. The dynamic performance test device for turbomolecular pump magnetic bearings loaded with simulated gas according to claim 2, characterized in that: The diameter of the ball (45) is not less than the inner diameter of the probe housing (43).

5. The device for testing dynamic performance of turbomolecular pump magnetic bearings with simulated gas loading according to claim 2, characterized in that: The upper three-axis mobile platform (2) comprises a first X-axis mobile part (21) which is symmetrically arranged, wherein two of the first X-axis mobile parts (21) are fixedly connected to the top of the frame (1), a first Y-axis mobile part (22) is fixedly connected between the mobile ends of the two first X-axis mobile parts (21), a first Z-axis mobile part (23) is fixedly connected to the mobile end of the first Y-axis mobile part (22), and a mobile end of the first Z-axis mobile part (23) is fixedly connected to one of the shells (41).

6. The device for testing dynamic performance of turbomolecular pump magnetic bearings with simulated gas loading according to claim 2, characterized in that: The side three-axis mobile platform (3) comprises a second Z-axis mobile part (33) which is symmetrically arranged, wherein two of the second Z-axis mobile parts (33) are fixedly connected to the side wall of the frame (1), a second X-axis mobile part (31) is fixedly connected between the mobile ends of the two second Z-axis mobile parts (33), a second Y-axis mobile part (32) is fixedly connected to the mobile end of the second X-axis mobile part (31), and a mobile end of the second Y-axis mobile part (32) is fixedly connected to another of the shells (41).

7. The device for testing dynamic performance of turbomolecular pump magnetic bearings with simulated gas loading according to claim 2, characterized in that: The visual detection component (5) comprises a second support (51) fixedly connected to the top crossbeam of the frame (1), and a camera (52) is fixedly connected to the bottom of the second support (51).

8. The device for testing dynamic performance of turbomolecular pump magnetic bearings with simulated gas loading according to claim 7, characterized in that: The camera (52) is arranged at an angle and is parallel to a plane formed by the two shells (41).

9. The device for testing dynamic performance of turbomolecular pump magnetic bearings with simulated gas loading according to claim 1, characterized in that: Reinforcing ribs (11) are respectively fixedly connected between adjacent support rods of the frame (1), and the reinforcing ribs (11) are arranged obliquely.

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