Turbine-drag cup composite pumping unit structure and magnetic suspension molecular pump

Abstract

The application discloses a turbine-pulley composite pumping unit structure and a magnetic suspension molecular pump, and relates to the technical field of vacuum obtaining equipment. The turbine-pulley composite pumping unit structure comprises multiple layers of dynamic sheets and multiple layers of static sheets which are alternately arranged along the axial direction, the multiple layers of dynamic sheets and the multiple layers of static sheets are both divided into front and rear sections along the axial direction, the dynamic sheets and the static sheets in the front section are all constructed as turbine blade structures, and each static sheet in the rear section comprises a composite turbine blade structure formed by a static sheet turbine blade tooth and a static sheet pulley structure, wherein, along the axial direction away from the front section, the radial proportion of the static sheet turbine blade tooth part gradually decreases, and the radial proportion of the static sheet pulley structure part gradually increases. The turbine-pulley composite pumping unit structure can solve the problems of insufficient pumping performance and the like in the prior art, and realizes the technical effects of improving the pumping efficiency and the compression ratio.

Description

Technical Field

[0001] This application relates to the field of vacuum acquisition equipment technology, and more specifically, to a turbine-traction disc composite pumping unit structure and a magnetic levitation molecular pump. Background Technology

[0002] Magnetic levitation molecular pumps, as oil-free vacuum generating devices, achieve pumping by transferring momentum to gas molecules through a high-speed rotating rotor. Their core performance depends on the structural design of the pumping unit. Currently, the mainstream pumping unit structures in the industry are mainly divided into three categories: pure turbine structure, turbine + traction cylinder structure, and turbine + traction disc structure. The pure turbine structure, with its large pumping area, exhibits a high pumping speed advantage in the high vacuum region (molecular flow state), achieving a compression ratio of up to 10 for heavy gases. 8 The above applies, but in high-pressure areas (close to the operating pressure of the backing pump), the pumping performance drops rapidly, and the operating pressure range is narrow (typically 10). -6 ~1Pa), and the compressibility ratio for light gases such as hydrogen and helium is only 10²~10. 4 The turbine + traction cylinder structure expands the working pressure range by adding a traction cylinder, maintaining good pumping capacity in the high-pressure range. However, the connection between the turbine stage and the traction cylinder is prone to backflow due to the abrupt change in gas flow pattern, and the small pumping area of ​​the traction cylinder groove becomes a performance bottleneck. The turbine + traction disc structure uses a disc-type traction stage to improve the outlet pressure and compression ratio, resulting in superior overall performance over a wide pressure range. However, it also suffers from interstage flow disorder, requiring an additional transition stage structure, and the traction disc area limits the overall pumping speed improvement.

[0003] Existing technical solutions have revealed multiple technical shortcomings in practical applications: pure turbine structures lack sufficient compression efficiency for light gases, failing to balance pumping speed and compression ratio; composite structures (turbine + traction cylinder / traction disc) suffer from backflow due to unreasonable interstage connection design, and require additional transition stages to optimize flow, resulting in increased overall height and structural complexity; in terms of performance, there is a significant difference in linear velocity between the inner and outer sides of the rotor (e.g., the linear velocity on the outer side of a 270mm diameter rotor is 382m / s, while on the inner side it is only 170m / s), far lower than the thermal motion speed of hydrogen molecules (1900m / s), making it difficult to improve the compression ratio while maintaining pumping speed. These problems restrict the application expansion of magnetic levitation molecular pumps in scenarios with wide pressure ranges and high / low gas compatibility. Summary of the Invention

[0004] The main objective of this application is to provide a turbine-traction disc composite pumping unit structure and a magnetic levitation molecular pump using the same structure, so as to solve the problems of insufficient pumping performance in the prior art and achieve the technical effect of improving pumping efficiency and compression ratio.

[0005] To achieve the above objectives, the first aspect of this application proposes a turbine-traction disc composite pumping unit structure for a magnetically levitated molecular pump, comprising multiple layers of moving blades and multiple layers of stationary blades alternately stacked along the axial direction. Both the moving blades and the stationary blades are divided into a front region and a rear region along the axial direction. The moving blades and stationary blades located in the front region are constructed as turbine blade structures, and each stationary blade located in the rear region comprises a composite turbine blade structure formed by stationary blade turbine tooth and stationary blade traction disc structure. In this case, along the axial direction away from the front region, the radial proportion of the stationary blade turbine tooth portion gradually decreases, while the radial proportion of the stationary blade traction disc structure portion gradually increases.

[0006] Furthermore, the stationary blade turbine blade tooth ring is located on the outer periphery of the stationary blade traction disc structure, and the two are interconnected on the same planar base. The gas transmission angle of the stationary blade located in the rear section gradually decreases from top to bottom along the axial direction.

[0007] Furthermore, the gas transmission tilt angle of the stationary plate located in the rear region is 1.5-2 times that of the stationary plate located axially upward.

[0008] Furthermore, a traction groove is formed on the surface of the stationary blade traction disc structure. The traction groove extends radially along the stationary blade and forms a traction disc transition section for continuous momentum transfer between the stationary blade turbine blade teeth and the stationary blade traction disc structure. The profile of the traction groove is any one or more combinations of circular arc profile, Archimedean spiral, logarithmic spiral, and circular profile.

[0009] Furthermore, the upper end face of the stationary blade of the composite turbine blade structure is designed to guide the gas to migrate radially from the outside to the inside along the stationary blade traction disc structure, and the lower end face is designed to guide the gas to migrate radially from the inside to the outside along the stationary blade traction disc structure, forming a bidirectional radial air extraction structure.

[0010] Furthermore, each moving blade in the rear section region includes a composite turbine blade structure formed by moving blade turbine teeth and moving blade disk structure, wherein the length of the moving blade turbine teeth gradually decreases along the axial direction away from the front section region, and the number of moving blade turbine teeth gradually increases along the axial direction away from the front section region.

[0011] Furthermore, the number of turbine blade teeth on the moving vanes in the front region and the number of turbine blade teeth on the moving vanes in the rear region both show an increasing trend from top to bottom along the axial direction.

[0012] Furthermore, the moving blade turbine blade teeth and moving blade disk structure, as well as the stationary blade turbine blade teeth and stationary blade traction disk structure, are all integrally machined structures.

[0013] Furthermore, it also includes a transition stage and at least one traction disc stage structure, which are located at the axial end of the main structure formed by the front and rear sections.

[0014] According to a second aspect of this application, a magnetically levitated molecular pump is proposed. The magnetically levitated molecular pump includes: a pump body; a magnetically levitated bearing system disposed within the pump body; and the aforementioned turbine-traction disc composite pumping unit structure, which is suspended and supported at the center of the pump body via the magnetically levitated bearing system; wherein the air inlet of the pump body is directly connected to the space where the pumping stage of the turbine-traction disc composite pumping unit structure is located, and the front-stage exhaust port of the pump body is fluidly connected to the innermost output end of the stationary vane traction disc structure.

[0015] The technical solutions provided by the embodiments of this application may include the following beneficial effects: In this application, the integrated design of the turbine extraction structure and the traction disc extraction structure (i.e., composite vane) enables the extraction unit to adapt to both high vacuum and medium-low vacuum environments. The gradient configuration of the pure turbine structure in the front section and the composite vane structure in the rear section adapts to the density variation characteristics of the gas within the pump chamber, thereby avoiding the performance bottleneck of a single structure over a wide pressure range. The gradual change in the proportion of the vane turbine blades to the vane traction disc structure in the rear section enables a smooth transition in gas momentum transfer, reducing flow field disturbance and energy loss, thus effectively improving the overall compression efficiency and compression ratio. Furthermore, the composite turbine blade structure enhances the structural stability of the vanes, maintaining profile accuracy even under high-speed airflow impact, thereby effectively extending the service life of the turbine-traction disc composite extraction unit structure. Simultaneously, compared to existing turbine-traction disc technologies, it also reduces the overall structural size and space occupied. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings: Figure 1 A partial structural schematic diagram of the turbine-traction disc composite extraction unit structure provided in this application; Figure 2 for Figure 1 A partial schematic diagram of the stationary plate structure in the rear section of the turbine-traction disc composite extraction unit structure shown. Figure 3 for Figure 2 A schematic diagram of the axial cross-sectional structure of the stationary plate shown; Figure 4 for Figure 1A partial schematic diagram of the moving plate structure in the rear section of the turbine-traction disc composite extraction unit structure shown; Figure 5 A schematic diagram of the gas flow direction of the turbine-traction disc composite extraction unit structure provided in this application. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0018] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0019] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0020] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0021] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linked," and "socketing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] According to a first aspect of this application, a turbine-traction disc composite pumping unit structure 100 is provided for a magnetically levitated molecular pump. Figure 1 A partial structure of the turbine-traction disc composite extraction unit structure 100 provided according to this application is shown. (See attached diagram.) Figure 1 As shown, the turbine-traction disc composite extraction unit structure 100 includes multiple layers of moving blades 1 and multiple layers of stationary blades 2 alternately stacked along the axial direction. Both the moving blades 1 and the stationary blades 2 are divided into a front region 101 and a rear region 102 along the axial direction. The moving blades 1 and stationary blades 2 located in the front region 101 are constructed as turbine blade structures. Please refer to... Figure 2 Each stationary blade 2 located in the rear region 102 includes a composite turbine blade structure formed by stationary blade turbine blade teeth 21 and stationary blade traction disk structure 22. In this case, along the axial direction away from the front region 101, the radial proportion of the stationary blade turbine blade teeth 21 gradually decreases, while the radial proportion of the stationary blade traction disk structure 22 gradually increases.

[0023] According to an embodiment of the present invention, the turbine-traction disk composite pumping unit structure 100, during the assembly of a magnetic levitation molecular pump, involves alternatingly stacking multiple layers of moving blades 1 and stationary blades 2 in an axial, front-to-back sequence. In the front section 101, both the moving blades 1 and stationary blades 2 are uniformly constructed using the pure turbine blade structure of the prior art. In a first embodiment, the moving blades 1 in the rear section 102 are constructed using the pure turbine blade structure of the prior art, while the stationary blades 2 are constructed using a composite turbine blade structure comprising stationary blade turbine teeth 21 and a stationary blade traction disk structure 22. In another embodiment (i.e., in conjunction with the moving blade 1 structure provided below), the moving blades 1 in the rear section 102 are also constructed using a composite turbine blade structure (detailed below). Based on the gas compression gradient requirements, composite stationary blades 2 (i.e., composite turbine blade structures) are installed sequentially with decreasing proportions of stationary blade turbine teeth 21 and increasing proportions of stationary blade traction disk structures 22. During assembly, the axial alignment accuracy of the moving blades 1 and stationary blades 2 must be ensured so that the pure turbine blade structure of the front section 101 and the composite turbine blade structure of the rear section 102 form a continuous transition pumping channel. Combination Figure 5As shown, during equipment operation, a vacuum sensor installed inside the pump body detects the vacuum environment parameters within the pump chamber in real time and feeds them back to the control system. The control system controls the drive motor of the moving vane 1 according to these vacuum environment parameters to adjust the rotational speed of the moving vane 1. When gas enters the front section 101, the pure turbine blade structure forms the pumping stage, which first performs preliminary compression on the gas. As the gas flows backward, the composite stationary vane 2 in the rear section 102 gradually enhances the capture and transport capacity of gas molecules through the synergistic effect of the turbine blade teeth and the traction disc structure, ultimately achieving efficient exhaust.

[0024] Through the above-described configuration, the integrated design of the turbine extraction structure and the traction disk extraction structure (i.e., the composite stationary vane 2) enables the extraction unit to adapt to both high vacuum and medium-low vacuum environments. The gradient configuration of the pure turbine structure in the front section 101 and the composite stationary vane 2 structure in the rear section 102 adapts to the density variation characteristics of the gas within the pump chamber, thereby avoiding the performance bottleneck of a single structure over a wide pressure range. The gradual change in the proportion of the stationary vane turbine blade teeth 21 to the stationary vane traction disk structure 22 in the rear section 102 enables a smooth transition in gas momentum transfer, reducing flow field disturbances and energy loss, thus effectively improving the overall compression efficiency and compression ratio. Furthermore, the composite turbine blade structure enhances the structural stability of the stationary vane 2, maintaining its profile accuracy even under high-speed airflow impact, thereby effectively extending the service life of the turbine-traction disk composite extraction unit structure 100. Simultaneously, compared to existing turbine-traction disk technologies, it also reduces the overall structural size and space occupied.

[0025] In some embodiments, both the stationary sheet 2 and the moving sheet 1 can be configured as 8 layers, with layers 1 to 4 being the front region 101 and layers 5 to 8 being the rear region 102.

[0026] Please refer to Figure 2 and Figure 3 Furthermore, the stationary blade turbine blade teeth 21 are arranged around the outer periphery of the stationary blade traction disc structure 22, and the two are interconnected on the same plane base. The gas transmission angle α of the stationary blade 2 located in the rear section region 102 gradually decreases from top to bottom along the axial direction.

[0027] In this embodiment, based on the gas compression requirements of the rear region 102, stationary vanes 2 with gradually decreasing gas transmission angles α are machined sequentially from top to bottom along the axial direction, creating a smooth transition in the angle changes between adjacent stationary vanes 2. This gradient configuration matches the characteristic of increasing gas density along the flow path, avoiding airflow separation caused by abrupt changes in angle, thereby further improving compression efficiency. Furthermore, the angle gradient design allows gas molecules to obtain continuous momentum transfer as they flow through the rear region 102, gradually increasing the directional gas velocity, effectively reducing the backflow rate, and minimizing local energy loss, thus improving overall pumping performance. In addition, the arrangement of the stationary vane turbine blade teeth 21 around the outer periphery of the traction disc structure forms a radial gas transport channel from the outer periphery to the center. Combined with the interconnected design on the planar base, this reduces gas flow resistance. Simultaneously, the integrated structure on the same planar base enhances the overall rigidity of the stationary vanes 2, making them less prone to deformation under high-speed airflow impact, ensuring structural stability during long-term operation.

[0028] Furthermore, the gas transmission angle α of the stationary plate 2 located in the rear region 102 is 1.5-2 times that of the stationary plate 2 located axially upward. Preferably, the gas transmission angle α can range from 2° to 4°, wherein the gas transmission angle α of the rear stationary plate 2 located axially upward is 4°, and the gas transmission angle α of the rear stationary plate 2 located axially downward is 2°.

[0029] In this embodiment, the gradient setting of the gas transmission tilt angle α within the range of 2° to 4° can effectively adapt to the gradually increasing gas density in the subsequent region 102, thereby avoiding the problem of insufficient airflow adaptability caused by a single tilt angle. Furthermore, the upper axial stationary plate 2 adopts a larger tilt angle, which can effectively capture high-speed airflow and transfer momentum, while the lower stationary plate 2 has a smaller tilt angle, which enhances the compression capacity of high-density gas, thereby further forming a segmented and synergistic pumping effect.

[0030] Please continue to refer to Figure 2 and Figure 3 Furthermore, a traction groove 221 is formed on the surface of the stationary blade traction disc structure 22. The traction groove 221 extends radially along the stationary blade 2 and forms a traction disc transition section for continuous momentum transfer between the stationary blade turbine blade tooth 21 and the stationary blade traction disc structure 22. The profile of the traction groove 221 is any one or more combinations of a circular arc profile, an Archimedean spiral, a logarithmic spiral, and a circular profile.

[0031] In this embodiment, the selection of various profiles can be adapted to different gas molecular masses and flow velocity characteristics. By optimizing the profiles, the gas can form a stable directional flow in the tank, thereby improving the traction efficiency.

[0032] Please continue to refer to Figure 2and Figure 3 Furthermore, the upper end face of the stationary blade 2 of the composite turbine blade structure is configured to guide the gas to migrate radially from the outside to the inside along the stationary blade traction disk structure 22 L1, and the lower end face is configured to guide the gas to migrate radially from the inside to the outside along the stationary blade traction disk structure 22 L2, forming a bidirectional radial air extraction structure.

[0033] In this embodiment, the upper and lower surfaces of the stationary vane 2 of the composite turbine blade structure form traction grooves with opposite rotation directions. The bidirectional radial air extraction structure causes the upper and lower surfaces of the stationary vane 2 to simultaneously form opposite gas migration paths, effectively increasing the gas throughput per unit time and further improving the overall air extraction rate. The complementary airflow migration directions of the upper and lower surfaces can balance the pressure distribution within the pump chamber, reduce local pressure fluctuations caused by unidirectional air extraction, and enhance operational stability. The bidirectional flow channel design makes full use of the disk space of the stationary vane 2, expanding the air extraction area without increasing the axial dimension, thus achieving a compact structure.

[0034] Please refer to Figure 4 Furthermore, each moving blade 1 located in the rear region 102 may include a composite turbine blade structure formed by moving blade turbine teeth 11 and moving blade disk structure 12. The length of the moving blade turbine teeth 11 decreases stepwise along the axial direction away from the front region 101, and the number of moving blade turbine teeth 11 increases stepwise along the axial direction away from the front region 101.

[0035] In this embodiment, i.e. another implementation, the moving plate 1 can adjust the size and number of moving plate turbine blade teeth 11 sequentially from the front region 101 to the rear along the axial direction according to the gas compression requirements of the rear region 102, so that the length of the moving plate turbine blade teeth 11 is gradually shortened and the number is gradually increased, while maintaining the integrated molding of the moving plate disk structure 12 and the moving plate turbine blade teeth 11.

[0036] Through the above configuration, the length of the moving turbine blade teeth 11 is gradually shortened along the axial direction, which can further adapt to the increased gas density in the rear region 102, avoiding airflow blockage caused by excessively long blades, and reducing the impact load of high-density gas on the moving turbine blade teeth 11. Furthermore, the configuration of gradually increasing number of moving turbine blade teeth 11 also increases the probability of contact with gas molecules, improving the gas capture and compression capabilities, and forming a segmented progressive pumping effect. Furthermore, the gradient change of the moving turbine blade teeth 11 also allows the gas to obtain continuous compression as it flows through the rear region 102, effectively increasing the directional movement velocity of gas molecules, reducing the backflow rate, and reducing local energy loss caused by abrupt parameter changes in the moving turbine blade teeth 11, thus improving the overall pumping efficiency of the molecular pump. In addition, the composite turbine blade structure also enhances the overall rigidity of the moving blade 1, making it less prone to deformation or vibration under high-speed rotation conditions, ensuring structural stability during long-term operation.

[0037] In some embodiments, the number of moving blade turbine blade teeth 11 of the moving blade 1 in the rear region 102 can be gradually increased from 38 to 60.

[0038] Furthermore, the number of turbine blade teeth of the moving blade 1 in the front region 101 and the number of turbine blade teeth 11 of the moving blade in the rear region 102 generally increase from top to bottom along the axial direction.

[0039] In this embodiment, the number of turbine blade teeth 11 on the moving blades 1 in the front section 101 and the moving blade turbine blade teeth 11 in the rear section 102 are designed to increase axially from top to bottom. This design directly adapts to the characteristic of the gas density gradually increasing during the flow of gas in the pump chamber. This allows the rear section 102 to effectively interact with high-density gas molecules through more turbine blade teeth on the moving blades 1, thereby improving compression efficiency. The relatively fewer turbine blade teeth in the front section 101 reduce the flow resistance to low-density gas, resulting in a good pumping effect. The increased number of blade teeth in the rear section 102 enhances the ability to capture high-density gas, forming a segmented and adapted pumping mechanism.

[0040] Furthermore, the moving blade turbine blade teeth 11 and the moving blade disk structure 12, the stationary blade turbine blade teeth 21 and the stationary blade traction disk structure 22 are all integrally machined structures.

[0041] In this embodiment, on the one hand, the integrated machined structure eliminates the connection gap between the blade teeth and the disk, preventing gas leakage or eddies at the joint and improving pumping efficiency. On the other hand, the overall structure enhances the fatigue resistance of the blades, enabling them to withstand greater centrifugal force and gas impact force under high-speed rotation conditions, thus extending their service life. Finally, eliminating the separate assembly process reduces the problem of uneven blade tooth gaps caused by assembly errors, lowering production and debugging costs.

[0042] Please return Figure 1 Furthermore, it may also include a transition stage 3 and at least one traction disc stage structure 4, wherein the transition stage 3 and at least one traction disc stage structure 4 are disposed at the axial end of the main structure formed by the front section region 101 and the rear section region 102.

[0043] In this embodiment, the traction disk stage structure 4 includes a moving traction disk and a stationary traction disk, and the gas is axially compressed under the action of the traction grooves of the moving and stationary traction disks. Depending on the ultimate vacuum requirement of the molecular pump, a transition stage 3 and the traction disk stage structure 4 can be sequentially configured at the axial end formed by the front region 101 and the rear region 102. The transition stage 3 can adopt a transition stage configuration as in the prior art, and the number of layers in the traction disk stage structure 4 can be determined according to the target vacuum environment. Through this configuration, the transition stage 3 and the traction disk stage structure 4 further compress the gas discharged from the main structure, effectively reducing the exhaust pressure at the rear end and improving the ultimate vacuum performance of the molecular pump.

[0044] According to a second aspect of this application, a magnetically levitated molecular pump is provided, the magnetically levitated molecular pump comprising: a pump body 200 (e.g., ... Figure 1 (As shown); a magnetic levitation bearing system, which is disposed within the pump body 200; and the aforementioned turbine-traction disc composite extraction unit structure 100, which is suspended and supported at the center of the pump body 200 by the magnetic levitation bearing system. The air inlet of the pump body 200 is directly connected to the space containing the extraction stage of the turbine-traction disc composite extraction unit structure 100, and the front exhaust port of the pump body 200 is fluidly connected to the innermost output end of the stationary plate traction disc structure 22.

[0045] According to an embodiment of the magnetic levitation molecular pump of the present invention, during the assembly stage, the turbine-traction disc composite pumping unit structure 100 is positioned at the center of the pump body 200 by the radial and axial electromagnetic bearing assemblies of the magnetic levitation bearing system, and the gap between the sensor and the rotor is adjusted to ensure levitation accuracy. When installing the pump body 200, the air inlet flange is aligned with the central axis of the cavity where the pumping stage is located, and the direct communication between the air inlet and the pumping stage space is ensured by a sealing gasket; the pre-stage exhaust port is connected to the annular flow channel at the innermost output end of the stationary plate traction disc structure 22 through a guide pipe to ensure that the gas flow path has no right-angle turns.

[0046] Through the above settings, the fluid communication design between the pre-exhaust port and the inner output end of the stationary traction disc structure 22 allows the compressed gas to directly enter the exhaust system, avoiding the formation of eddies in the pump chamber, effectively reducing the backflow rate, and combined with magnetic levitation technology, enabling the molecular pump to operate efficiently over a wide speed range.

[0047] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0048] Obviously, those skilled in the art should understand that the various units or steps of this application described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device, or fabricating them separately as individual integrated circuit modules, or fabricating multiple modules or steps into a single integrated circuit module. Thus, this application is not limited to any particular combination of hardware and software.

[0049] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A turbine-traction disc composite pumping unit structure for a magnetically levitated molecular pump, comprising multiple layers of moving plates and multiple layers of stationary plates alternately stacked along the axial direction, characterized in that: Both the multi-layer moving blades and the multi-layer stationary blades are divided into a front region and a rear region along the axial direction. The moving blades and stationary blades located in the front region are constructed as turbine blade structures. Each stationary blade located in the rear region includes a composite turbine blade structure formed by stationary blade turbine teeth and stationary blade traction disc structure. Along the axial direction away from the front region, the radial proportion of the stationary blade turbine teeth gradually decreases, while the radial proportion of the stationary blade traction disc structure gradually increases.

2. The turbine-traction disc composite extraction unit structure according to claim 1, characterized in that, The stationary blade turbine tooth ring is located on the outer periphery of the stationary blade traction disc structure, and the two are interconnected on the same planar base. The gas transmission angle of the stationary blade located in the rear section region gradually decreases from top to bottom along the axial direction.

3. The turbine-traction disc composite extraction unit structure according to claim 2, characterized in that, The gas transmission tilt angle of the stationary plate located in the rear section region is 1.5-2 times that of the stationary plate located axially upward.

4. The turbine-traction disc composite extraction unit structure according to any one of claims 1-3, characterized in that, A traction groove is formed on the surface of the stationary blade traction disc structure. The traction groove extends radially along the stationary blade and forms a traction disc transition section for continuous momentum transfer between the stationary blade turbine blade teeth and the stationary blade traction disc structure. The profile of the traction groove is any one or more combinations of a circular arc profile, an Archimedean spiral, a logarithmic spiral, and a circular profile.

5. The turbine-traction disc composite extraction unit structure according to claim 4, characterized in that, The upper end face of the stationary blade of the composite turbine blade structure is configured to guide gas to migrate radially from the outside to the inside along the stationary blade traction disc structure, and the lower end face is configured to guide gas to migrate radially from the inside to the outside along the stationary blade traction disc structure, forming a bidirectional radial air extraction structure.

6. The turbine-traction disc composite extraction unit structure according to claim 1, characterized in that, Each moving blade located in the rear section region includes a composite turbine blade structure formed by moving blade turbine teeth and moving blade disk structure, wherein the length of the moving blade turbine teeth is gradually shortened along the axial direction away from the front section region, and the number of the moving blade turbine teeth is gradually increased along the axial direction away from the front section region.

7. The turbine-traction disc composite extraction unit structure according to claim 6, characterized in that, The number of turbine blade teeth of the moving plate in the front section region and the number of turbine blade teeth of the moving plate in the rear section region generally increase from top to bottom along the axial direction.

8. The turbine-traction disc composite extraction unit structure according to claim 6, characterized in that, The moving turbine blade teeth and the moving disc structure, as well as the stationary turbine blade teeth and the stationary traction disc structure, are all integrally machined structures.

9. The turbine-traction disc composite extraction unit structure according to claim 1, characterized in that, It also includes a transition stage and at least one traction disc stage structure, wherein the transition stage and at least one traction disc stage structure are disposed at the axial end of the main structure formed by the front section and the rear section.

10. A magnetically levitated molecular pump, characterized in that, include: Pump body; A magnetic levitation bearing system is installed inside the pump body; as well as According to any one of claims 1 to 8, the turbine-traction disc composite pumping unit structure is suspended and supported at the center of the pump body by the magnetic levitation bearing system; The air inlet of the pump body is directly connected to the space where the pumping stage of the turbine-traction disc composite pumping unit structure is located, and the front exhaust port of the pump body is fluidly connected to the innermost output end of the stationary plate traction disc structure.

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