Exhaust structure, molecular pump and process equipment

Abstract

The invention provides an exhaust structure, a molecular pump and process equipment. The exhaust structure comprises a first exhaust part and a second exhaust part. And one of the first exhaust part and the second exhaust part is sleeved outside the other one of the first exhaust part and the second exhaust part. The first exhaust part and the second exhaust part are used for relative rotation. A spiral protrusion is arranged on the side wall, close to the second exhaust part, of the first exhaust part. The side wall face, close to the first exhaust piece, of the second exhaust piece is a smooth face. The spiral protrusions and the second exhaust parts are arranged at intervals. A groove is formed in the side, close to the second exhaust part, of the spiral protrusion. The grooves extend in the spiral direction of the spiral protrusions. In the process that gas flows from the gas outlet side to the gas inlet side along the gap between the spiral protrusion and the second exhaust part, the gas flow forms vortexes at the positions corresponding to the grooves, the vortexes block the gap so as to restrain the gas from flowing from the gas outlet side to the gas inlet side along the gap, gap backflow of the exhaust structure is reduced, and the exhaust effect is improved. The gas pumping capacity and pumping efficiency of the exhaust structure are improved, and the vacuum capacity of the molecular pump is improved.

Description

Technical Field

[0001] This application relates to the technical field of vacuum equipment, and particularly to an exhaust structure, a molecular pump, and a process equipment. Background Art

[0002] A molecular pump is a vacuum pump used for efficiently extracting low-pressure gas to obtain a high vacuum, and is widely used in high-tech fields such as semiconductors, optoelectronic displays, and materials research. In the development of molecular pump technology, the mainstream architecture is the series connection of a turbine stage and a traction stage. The traction stage is used to enhance the pumping capacity of the gas to solve the problem of insufficient pumping speed of the turbine stage for high-pressure gas. The traction stage is provided with spiral grooves. The traction stage guides the gas to move along the spiral grooves through a rotating rotor, so that the gas is discharged from the low-pressure side to the high-pressure side. However, in a traditional molecular pump, there is gap backflow between the stator and the rotor of the traction stage, which will cause the pumping capacity of the traction stage for the gas to decrease. Summary of the Invention

[0003] Embodiments of this application provide an exhaust structure, a molecular pump, and a process equipment to solve the problem that the gap backflow of the traction stage reduces the pumping capacity of the traction stage for the gas.

[0004] In a first aspect, this application provides an exhaust structure, and the exhaust structure is applicable to a molecular pump. The exhaust structure includes a first exhaust member and a second exhaust member. One of the first exhaust member and the second exhaust member is sleeved outside the other. The first exhaust member and the second exhaust member are used for relative rotation. A spiral protrusion is provided on a side wall of the first exhaust member close to the second exhaust member. A side wall surface of the second exhaust member close to the first exhaust member is a smooth surface. The spiral protrusion and the second exhaust member are arranged at intervals. A groove is provided on a side of the spiral protrusion close to the second exhaust member. The groove extends along the spiral direction of the spiral protrusion.

[0005] In the embodiment of the present application, a groove is set on the side of the spiral protrusion close to the second exhaust member, and the groove extends along the spiral direction of the spiral protrusion. In the process of gas flowing from the outlet side to the inlet side along the gap between the spiral protrusion and the second exhaust member, since the flow area of ​​the gap at the position corresponding to the groove is larger than the flow area of ​​the gap at other positions, the groove wall of the groove is bent relative to the spiral protrusion toward the side wall of the second exhaust member. When the reflux gas flows through the groove, the pressure, flow velocity, flow direction, etc. of the airflow changes, and the groove wall of the groove guides the airflow, so that the airflow and the groove wall of the groove are separated, so that the airflow will be in the corresponding groove under the disturbance of the groove. The eddy current will drive the gas to collide with other gases in the gap, so as to form a "gas wall" at the position of the gap corresponding to the groove, that is, the eddy current blocks the gap, thereby suppressing the gas from flowing along the gap from the gas outlet side to the gas inlet side, greatly reducing the gap backflow of the exhaust structure, and then, on the basis of not changing the gap width of the gap, that is, not increasing the processing accuracy and assembly difficulty of the molecular pump, improving the sealing performance between the spiral protrusion and the second exhaust member, which is conducive to fully allowing the gas to flow along the spiral groove toward the gas outlet side, improving the pumping capacity and efficiency of the exhaust structure for the gas, and improving the vacuum capacity of the molecular pump.

[0006] In combination with the first aspect, in certain implementations of the first aspect, the groove extends at least one circle around the rotation center line of the first exhaust member and the second exhaust member. When the exhaust structure is evacuating air, the groove can form a vortex on the entire circumference of the exhaust structure, thereby blocking the entire circumference of the exhaust structure, fully suppressing gap backflow, and improving the exhaust capacity of the exhaust structure.

[0007] In combination with the first aspect, in certain implementations of the first aspect, the exhaust structure has an air inlet side and an air outlet side, and the groove extends from an end of the spiral protrusion close to the air inlet side to an end of the spiral protrusion close to the air outlet side. The extension length of the groove is the same as the extension length of the spiral protrusion, so that vortices are formed at all locations of the gap along the spiral direction of the spiral protrusion, thereby fully suppressing the gap backflow.

[0008] In combination with the first aspect, in some implementations of the first aspect, the groove includes a plurality of sub-groove segments, and the plurality of sub-groove segments are sequentially spaced along the spiral direction of the spiral protrusion. Each sub-groove segment can suppress gap backflow at a corresponding position of the gap between the spiral protrusion and the exhaust structure.

[0009] In combination with the first aspect, in some implementations of the first aspect, on a projection plane perpendicular to the rotation center line of the first exhaust member and the second exhaust member, the orthographic projections of the plurality of sub-groove segments are connected to form a ring, or the orthographic projections of the plurality of sub-groove segments form at least one arc segment. Through the common cooperation of the plurality of sub-groove segments, it is possible to suppress the gap reverse flow uniformly on the circumference of the exhaust structure, thereby improving the air extraction ability of the exhaust structure.

[0010] In combination with the first aspect, in some implementations of the first aspect, the exhaust structure has an air inlet side and an air outlet side, and the depth of the groove near the air inlet side is greater than or equal to the depth of the groove near the air outlet side. On the one hand, it can make the airflow have a larger flow-through area near the air outlet side of the groove. When the gas flows from the side of the groove near the air inlet side to the side of the groove near the air outlet side, the airflow expands in volume, and the pressure, flow velocity, flow direction, etc. of the airflow change, thereby exciting the formation of eddy currents in the airflow. On the other hand, when the airflow flows to the groove wall on the side near the air outlet side of the groove, due to the collision effect of the groove wall, the groove wall guides the flow direction of the airflow, so that the airflow flowing out of the groove intersects and collides with the airflow near the second exhaust member, which is conducive to the formation of eddy currents, and the collision between the airflow and the groove wall of the groove is also conducive to the formation of eddy currents, thereby effectively suppressing the gap reverse flow and improving the air extraction ability of the exhaust structure.

[0011] In combination with the first aspect, in some implementations of the first aspect, along the direction from the air inlet side to the air outlet side of the exhaust structure, the groove is located between two opposite side surfaces of the spiral protrusion. By having the groove located between two opposite side surfaces of the spiral protrusion, the two opposite side surfaces of the spiral protrusion can be prevented from being penetrated by the groove, and the increase in the gap width corresponding to the gap between the spiral protrusion and the second exhaust member at the two side surfaces can be avoided, so that the gap width at this position is the same as the gap width at the position where the groove is not provided in the gap, which is conducive to reducing the gas entering the gap and improving the air extraction efficiency of the exhaust structure.

[0012] In combination with the first aspect, in some implementations of the first aspect, along the direction from the intake side to the outlet side of the exhaust structure, the ratio of the width of the groove to the width of the spiral protrusion is 0.2 - 0.4. The ratio of the width of the groove to the width of the spiral protrusion being 0.2 - 0.4 is beneficial for the air flow to separate from the groove wall after entering the groove, enabling the groove to fully disturb the air flow. This is conducive to forming a vortex in the gap between the spiral protrusion and the second exhaust part, and is beneficial for increasing the intensity and size of the generated vortex, so that the vortex excited by the groove can fully fill the gap between the spiral protrusion and the second exhaust part and block the air flow in the gap, thereby enhancing the blocking effect of the vortex on the reverse flow in the gap. When the ratio of the width of the groove to the width of the spiral protrusion is less than 0.2, the width proportion of the groove on the spiral protrusion is insufficient. When the air flow passes through the gap between the spiral protrusion and the second exhaust part, it is difficult for the groove to excite a vortex that can fully fill the gap, and the intensity and size of the generated vortex are insufficient, resulting in insufficient inhibition of the reverse flow in the gap by the vortex. When the ratio of the width of the groove to the width of the spiral protrusion is greater than 0.4, the width proportion of the groove on the spiral protrusion is too large. When the air flow passes through the groove, the separation intensity between the air flow and the groove wall becomes smaller, which is not conducive to the separation of the air flow from the groove wall to form a vortex, thus leading to insufficient inhibition of the reverse flow in the gap.

[0013] In combination with the first aspect, in some implementations of the first aspect, the ratio of the depth of the groove to the width of the gap between the spiral protrusion and the second exhaust part is 0.5 - 0.75. The ratio of the depth of the groove to the width of the gap being 0.5 - 0.75 is beneficial for the air flow to separate from the groove wall when flowing into the groove, forming a vortex in the gap between the spiral protrusion and the second exhaust part, and is beneficial for increasing the intensity and size of the generated vortex. It is also beneficial for the vortex excited by the groove to be close to the middle position of the gap between the spiral protrusion and the second exhaust part and fully fill the gap between the spiral protrusion and the second exhaust part, thereby enhancing the blocking effect of the vortex on the reverse flow in the gap. When the ratio of the depth of the groove to the width of the gap is less than 0.5, the depth of the groove is insufficient, the intensity and size of the vortex excited by the groove are insufficient, and the vortex is difficult to fill the gap, resulting in insufficient inhibition of the reverse flow in the gap by the vortex. When the ratio of the depth of the groove to the width of the gap is greater than 0.75, the depth of the groove is too large, the separation intensity between the air flow and the groove wall is insufficient, which is not conducive to the formation of a vortex. After the vortex is generated, the intensity and size of the vortex are also insufficient, and the vortex will be accommodated in the groove, resulting in a large distance between the vortex and the side wall of the second exhaust part, and the disturbance effect of the vortex on the air flow in the gap is weak, thus leading to insufficient inhibition of the reverse flow in the gap by the vortex.

[0014] In combination with the first aspect, in certain implementations of the first aspect, the groove is provided in plurality, and the plurality of grooves are arranged side by side along the direction from the air inlet side to the air outlet side of the exhaust structure. The plurality of grooves are arranged side by side along the direction from the air inlet side to the air outlet side of the exhaust structure, so that the plurality of grooves can jointly suppress gap backflow and improve the exhaust capacity of the exhaust structure.

[0015] In combination with the first aspect, in certain implementations of the first aspect, the spiral protrusion and the first exhaust member are combined to form a spiral groove, the spiral groove extends along the spiral direction of the spiral protrusion, the exhaust structure has an air inlet side and an air outlet side, and the depth of the spiral groove close to the air inlet side is greater than or equal to the depth of the spiral groove close to the air outlet side. The depth of the spiral groove close to the air inlet side can be greater than the depth of the spiral groove close to the air outlet side, so that the space of the spiral groove close to the air inlet side can be greater than the space of the spiral groove close to the air outlet side. When the airflow flows along the spiral groove, a pressure gradient can be formed in the spiral groove, reducing the gas pressure at the position of the spiral groove close to the air inlet side, thereby reducing the pressure difference between the two opposite sides of the spiral protrusion, and then reducing the gas flow rate flowing into the gap, so as to cooperate with the groove to suppress the gap backflow.

[0016] In the second aspect, the present application provides a molecular pump, the molecular pump comprising a driving structure such as the exhaust structure described in any one of the above, the driving structure being in driving connection with one of the first exhaust member and the second exhaust member. By providing a groove on the spiral protrusion, a vortex is formed when the airflow in the gap flows through the groove, and the leaked airflow is suppressed by the vortex, so that the sealing performance between the spiral protrusion and the second exhaust member can be improved without changing the gap width of the gap, the pumping capacity and efficiency of the exhaust structure for gas can be improved, and the vacuum capacity of the molecular pump can be improved.

[0017] In combination with the second aspect, in certain implementations of the second aspect, the exhaust structure is used for a drag stage of the molecular pump.

[0018] In a third aspect, the present application provides a process device, the process device comprising a vacuum chamber and a molecular pump as described above, wherein the air inlet of the molecular pump is connected to the vacuum chamber. By providing a groove on the spiral protrusion, a vortex is formed when the airflow in the gap flows through the groove, and the leaked airflow is suppressed by the vortex, so that the sealing performance between the spiral protrusion and the second exhaust member can be improved without changing the gap width of the gap, the vacuum capacity of the molecular pump can be improved, the vacuum performance of the process device can be improved, and the vacuum degree of the vacuum chamber can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of a molecular pump provided in an embodiment of the present application;

[0020] Figure 2 yesFigure 1 An enlarged view of the traction stage of the molecular pump in

[0021] Figure 3 is Figure 1 A schematic structural diagram of the stator of the traction stage of the molecular pump in

[0022] Figure 4 A partial cross-sectional view of the molecular pump provided by an embodiment of the present application;

[0023] Figure 5 A partial sectional view of the exhaust structure provided by the first embodiment of the present application;

[0024] Figure 6 A partial sectional view of the exhaust structure provided by the second embodiment of the present application;

[0025] Figure 7 A partial sectional view of the exhaust structure provided by the third embodiment of the present application;

[0026] Figure 8 A partial sectional view of the exhaust structure provided by the fourth embodiment of the present application;

[0027] Figure 9 A partial sectional view of the exhaust structure provided by the fifth embodiment of the present application;

[0028] Figure 10 A partial sectional view of the exhaust structure provided by the sixth embodiment of the present application;

[0029] Figure 11 A developed view of the first exhaust member in the circumferential direction provided by some embodiments of the present application;

[0030] Figure 12 A developed view of the first exhaust member in the circumferential direction provided by some other embodiments of the present application;

[0031] Figure 13 A partial cross-sectional view of the molecular pump provided by some embodiments of the present application;

[0032] Figure 14 A flow field simulation diagram of the exhaust structure provided by the embodiment of the present application and the exhaust structure in the comparative example;

[0033] Figure 15 A structural block diagram of the process equipment provided by the embodiment of the present application.

[0034] Explanation of reference numerals:

[0035] 1000 - Process equipment; 1 - Molecular pump; 21 - Pump housing; 210 - Accommodating cavity; 201 - Inlet; 202 - Outlet; 31 - Stator; 311 - Turbine - stage stator; 312 - Traction - stage stator; 32 - Rotor; 321 - Turbine - stage rotor; 322 - Traction - stage rotor; 10 - Exhaust structure; 101 - Inlet side; 102 - Outlet side; 11 - First exhaust part; 111 - Spiral protrusion; 1111 - Side; 112 - Spiral groove; 113 - Gap; 114 - Groove; 1141 - Sub - groove section; 1142 - Groove group; 12 - Second exhaust part; C - Rotation center line; d1 - Depth; d2 - Gap width; w1 - Width; w2 - Width; 40 - Driving structure; 41 - Driving part; 42 - Rotating shaft; 43 - Mounting stator; 500 - Vacuum chamber; 510 - Working device. Detailed implementation manners

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0037] Referring to "embodiment" or "embodiment manner" herein means that the specific features, structures, or characteristics described in connection with the embodiment or embodiment manner can be included in at least one embodiment of the present application. The phrase appears at various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0038] It should be noted that the terms in the specification and claims of the present application and the above - mentioned drawings are only for describing specific embodiments and are not intended to limit the present application. The terms "first", "second", etc. in the specification and claims of the present application and the above - mentioned drawings are used to distinguish different objects, rather than to describe a specific order.

[0039] Please refer to Figure 1 and Figure 2 , Figure 1 which is a sectional view of the molecular pump 1 provided by the embodiment of the present application, Figure 2 is Figure 1Enlarged view of the traction stage of the medium molecular pump 1. The molecular pump 1 is a vacuum pump used for efficiently extracting low-pressure gas to obtain a high vacuum. Due to its excellent working stability and outstanding pumping efficiency, the molecular pump 1 has become a key device for obtaining clean high vacuum and ultra-high vacuum, and is widely used in high-tech fields such as semiconductors, optoelectronic displays, and materials research. The molecular pump 1 is often used to connect to a vacuum chamber to make the vacuum chamber have a high vacuum degree.

[0040] The molecular pump 1 includes a pump housing 21, a stator 31, a rotor 32, and a drive structure 40. A receiving cavity 210 is provided in the pump housing 21. The stator 31, the rotor 32, and the drive structure 40 are all arranged in the receiving cavity 210. An air inlet 201 and an air outlet 202 are also provided on the pump housing 21. The air inlet 201 and the air outlet 202 are respectively communicated with the receiving cavity 210. The air inlet 201 is used to connect to the vacuum chamber. The air outlet 202 is used to connect to the external environment. The stator 31 is fixed relative to the pump housing 21. The drive structure 40 is used to drive the rotor 32 to rotate relative to the stator 31. Among them, the drive structure 40 includes a driving member 41 and a rotating shaft 42. The rotating shaft 42 is fixedly connected to the rotor 32. The driving member 41 is used to drive the rotating shaft 42 to rotate, so that the rotating shaft 42 drives the rotor 32 to rotate relative to the stator 31. When the rotor 32 rotates relative to the stator 31, it can drive the gas to flow from the air inlet 201 to the air outlet 202, thereby realizing pumping the gas in the vacuum chamber to the external environment and obtaining a vacuum environment in the vacuum chamber.

[0041] Exemplarily, the molecular pump 1 can be a composite molecular pump. The molecular pump 1 includes a turbine stage and a traction stage. The turbine stage is used to increase the pumping speed of the molecular pump 1 for gas, and the traction stage is used to increase the pumping capacity of the molecular pump 1 for gas to compensate for the problem of insufficient pumping speed of the turbine stage for high-pressure gas, and to increase the compression ratio of the molecular pump, as well as to increase the pressure at the air outlet 202.

[0042] The rotor 32 includes a turbine-stage rotor 321 and a traction-stage rotor 322. The turbine-stage rotor 321 and the traction-stage rotor 322 are integrally formed and fixedly connected to the rotating shaft 42. The stator 31 includes a turbine-stage stator 311 and a traction-stage stator 312. The turbine-stage stator 311 is used to cooperate with the turbine-stage rotor 321 to form the turbine stage of the molecular pump 1. The turbine-stage rotor 321 includes multiple layers of rotor blades arranged in sequence along the axial direction of the rotating shaft 42. The rotor blades are inclined relative to the plane perpendicular to the central axis of the rotating shaft 42. The turbine-stage stator 311 includes multiple layers of stator blades arranged in sequence along the axial direction of the rotating shaft 42. The stator blades are inclined relative to the plane perpendicular to the central axis of the rotating shaft 42, and the inclination direction is opposite to that of the rotor blades. The rotor blades and the stator blades are arranged alternately along the axial direction of the rotating shaft 42. When the rotating shaft 42 drives the rotor blades and the stator blades to rotate, the rotor blades and the stator blades jointly push the gas molecules to move along the axial direction of the rotating shaft 42.

[0043] The traction stage stator 312 is used to cooperate with the traction stage rotor 322 to form the traction stage of the molecular pump 1. One of the traction stage rotor 322 and the traction stage stator 312 is sleeved outside the other and arranged at intervals. A spiral groove 112 is provided on the side wall of the traction stage rotor 322 facing the traction stage stator 312, or a spiral groove 112 is provided on the side wall of the traction stage stator 312 facing the traction stage rotor 322. When the traction stage rotor 322 rotates relative to the traction stage stator 312, the traction stage rotor 322 drives the gas to flow along the spiral groove 112 and flow in the direction from the air inlet 201 to the air outlet 202.

[0044] In some embodiments, the molecular pump 1 may also be a drag molecular pump. The stator 31 may be a drag stage stator 312 . The rotor 32 may be a drag stage rotor 322 .

[0045] Please also read Figure 1 , Figure 3 , Figure 4 and Figure 5 , Figure 3 yes Figure 1 A schematic structural diagram of the traction stage stator 312 of the molecular pump 1; Figure 4 is a partial cross-sectional view of a molecular pump 1 provided in an embodiment of the present application; Figure 5 It is a partial cross-sectional view of the exhaust structure 10 provided in the first embodiment of the present application. The exhaust structure 10 is suitable for the molecular pump 1. Specifically, the molecular pump 1 includes a driving structure 40 and an exhaust structure 10 in any embodiment of the present application. The exhaust structure 10 can be used for the traction stage of the molecular pump 1, that is, the traction stage can include the exhaust structure 10, and the function of the traction stage is realized by the exhaust structure 10. The driving structure 40 is connected to the exhaust structure 10 in a transmission manner to drive the exhaust structure 10 to work. The exhaust structure 10 includes a first exhaust member 11 and a second exhaust member 12. One of the first exhaust member 11 and the second exhaust member 12 is sleeved outside the other and arranged at intervals. Among them, one of the first exhaust member 11 and the second exhaust member 12 can be constructed as a hollow cylindrical structure, and the other is constructed as a cylindrical structure, and the cylindrical structure is sleeved outside the cylindrical structure, that is, the cylindrical structure is inserted into the hollow cylindrical structure. The central axis of the first exhaust member 11 and the second exhaust member 12 can be arranged to coincide. The first exhaust member 11 and the second exhaust member 12 are used for relative rotation. The driving structure 40 is drivingly connected to one of the first exhaust member 11 and the second exhaust member 12 to drive one of the first exhaust member 11 and the second exhaust member 12 to rotate relative to the other.

[0046] One of the first exhaust member 11 and the second exhaust member 12 can be used as a traction stage stator 312, and the other of the first exhaust member 11 and the second exhaust member 12 can be used as a traction stage rotor 322. The traction stage stator 312 is fixed to the pump housing 21 of the molecular pump 1, and the traction stage rotor 322 is transmission-connected to the driving structure 40. When the driving structure 40 drives the traction stage rotor 322 to rotate relative to the traction stage stator 312, the traction stage rotor 322 rotates around the rotation center line C.

[0047] Illustratively, in this embodiment, the first exhaust member 11 may be constructed as a hollow cylindrical structure and may serve as a traction stage stator 312 , the second exhaust member 12 may serve as a traction stage rotor 322 , and the first exhaust member 11 is sleeved outside the second exhaust member 12 .

[0048] In some embodiments, the first exhaust member 11 may be constructed as a hollow cylindrical structure and may serve as a traction stage rotor 322 , the second exhaust member 12 may serve as a traction stage stator 312 , and the first exhaust member 11 may be sleeved outside the second exhaust member 12 .

[0049] In some embodiments, the first exhaust member 11 can be used as a traction stage stator 312 , the second exhaust member 12 can be constructed as a hollow cylindrical structure and can be used as a traction stage rotor 322 , and the second exhaust member 12 is sleeved outside the first exhaust member 11 .

[0050] In some embodiments, the first exhaust member 11 can be used as a traction stage rotor 322 , the second exhaust member 12 can be constructed as a hollow cylindrical structure and can be used as a traction stage stator 312 , and the second exhaust member 12 is sleeved outside the first exhaust member 11 .

[0051] The exhaust structure 10 has an intake side 101 and an outlet side 102 disposed opposite to the intake side 101. The intake side 101 is the side of the exhaust structure 10 close to the intake port 201. The outlet side 102 is the side of the exhaust structure 10 close to the outlet port 202. The exhaust structure 10 is used to pump gas from the intake side 101 to the outlet side 102. A spiral protrusion 111 is provided on the side wall of the first exhaust member 11 close to the second exhaust member 12. The spiral protrusion 111 is spirally arranged along the extension direction of the rotation center line C. The side wall surface of the second exhaust member 12 close to the first exhaust member 11 is a smooth surface, that is, no protrusions or grooves are provided on the side wall surface of the second exhaust member 12 close to the first exhaust member 11, and it is a smooth cylindrical surface or conical surface. When the first exhaust member 11 is sleeved outside the second exhaust member 12, the spiral protrusion 111 is provided on the inner side wall of the first exhaust member 11, and the outer side wall of the second exhaust member 12 can be a smooth cylindrical surface or a smooth conical surface. When the second exhaust member 12 is sleeved outside the first exhaust member 11, the spiral protrusion 111 is provided on the outer side wall of the first exhaust member 11, and the inner side wall of the second exhaust member 12 can be a smooth cylindrical surface or a smooth conical surface. In this embodiment, the outer side wall of the second exhaust member 12 can be a smooth cylindrical surface, and the second exhaust member 12 is configured as a light cylinder.

[0052] A spiral groove 112 is formed by enclosing between the spiral protrusion 111 and the first exhaust member 11. The spiral groove 112 extends along the spiral direction of the spiral protrusion 111. The spiral protrusion 111 and the second exhaust member 12 are spaced apart to form a gap 113, and the gap 113 can prevent interference when the first exhaust member 11 and the second exhaust member 12 rotate relative to each other. The gap 113 communicates the spiral grooves 112 on both sides of the spiral protrusion 111.

[0053] When the exhaust structure 10 exhausts gas, when the first exhaust member 11 and the second exhaust member 12 rotate relative to each other, the gas located between the first exhaust member 11 and the second exhaust member 12 is driven, and under the guiding action of the spiral protrusion 111, the gas flows along the extension direction of the spiral groove 112. Figure 4 In, the arrow at the spiral groove 112 indicates the flow direction of the air flow. The spiral direction of the spiral protrusion 111 corresponds to the rotation direction of the traction stage rotor 322, so that the gas flows from the intake side 101 to the outlet side 102 along the spiral groove 112.

[0054] When the exhaust structure 10 exhausts gas, during the process of the gas flowing towards the outlet side 102, the pressure of the gas will gradually increase, that is, the gas pressure on the side of the spiral protrusion 111 close to the outlet side 102 is greater than the gas pressure on the side of the spiral protrusion 111 close to the intake side 101. Due to the pushing action of the pressure, a part of the gas will flow from the outlet side 102 to the intake side 101 along the gap 113, that is, form a gap reverse flow, which will cause the pumping efficiency of the exhaust structure 10 for the gas to decrease.

[0055] In the embodiment of the present application, a groove 114 is provided on the side of the spiral protrusion 111 close to the second exhaust member 12, and the groove 114 extends along the spiral direction of the spiral protrusion 111. The spiral extension direction of the groove 114 is the same as that of the spiral protrusion 111. Figure 5 The arrow at the gap 113 indicates the flow direction of the gas flow. During the process of the gas flowing from the outlet side 102 to the inlet side 101 along the gap 113, since the flow area of the gap 113 at the position corresponding to the groove 114 is larger than that of other positions of the gap 113, the groove wall of the groove 114 is bent relative to the side wall of the spiral protrusion 111 facing the second exhaust member 12. When the reflux gas flows through the groove 114, the pressure, flow rate, flow direction, etc. of the gas flow change, and through the guiding of the gas flow by the groove wall of the groove 114, it jointly causes the gas flow to separate from the groove wall of the groove 114. Therefore, the gas flow will form a vortex at the position corresponding to the groove 114 under the disturbance of the groove 114. The vortex will drive the gas to collide with other gases in the gap 113, thereby forming an "air wall" at the position of the gap 113 corresponding to the groove 114, that is, the vortex blocks the gap 113, and further inhibits the gas from flowing from the outlet side 102 to the inlet side 101 along the gap 113, greatly reducing the gap reflux of the exhaust structure 10. Thus, in the embodiment of the present application, without changing the gap width of the gap 113, that is, without increasing the processing accuracy and assembly difficulty of the molecular pump 1, the sealing performance between the spiral protrusion 111 and the second exhaust member 12 is improved, which is beneficial to fully make the gas flow along the spiral groove 112 towards the outlet side 102, and further improves the pumping capacity and pumping efficiency of the exhaust structure 10 for the gas, and improves the vacuum capacity of the molecular pump 1. In addition, in the embodiment of the present application, the side wall surface of the second exhaust member 12 close to the first exhaust member 11 is a smooth surface, so that the processing procedure of the second exhaust member 12 can remain unchanged. On the basis of realizing the inhibition of the gap reflux, the processing difficulty of the second exhaust member 12 is avoided, and the processing cost is reduced.

[0056] In this embodiment, the groove 114 extends at least one week around the rotation center line C of the first exhaust member 11 and the second exhaust member 12. Among them, the spiral protrusion 111 extends at least one week around the rotation center line C in a spiral manner. The groove 114 extends at least one week around the rotation center line C along the spiral protrusion 111. On the projection plane perpendicular to the rotation center line C, the orthographic projection of the groove 114 is connected to form a ring. Thus, when the exhaust structure 10 is pumping air, the groove 114 can form vortices on the entire circumference of the exhaust structure 10, thereby blocking the entire circumference of the exhaust structure 10, fully inhibiting the gap reflux, and improving the pumping capacity of the exhaust structure 10.

[0057] In this embodiment, the groove 114 extends from one end of the spiral protrusion 111 close to the intake side 101 to the other end of the spiral protrusion 111 close to the exhaust side 102. The extension length of the groove 114 is the same as that of the spiral protrusion 111, so that eddy currents are formed at all positions of the clearance 113 along the spiral direction of the spiral protrusion 111, thereby fully suppressing the reverse flow of the clearance. In some embodiments, the extension length of the groove 114 may be less than that of the spiral protrusion 111 to reduce the processing and manufacturing difficulty of the first exhaust member 11 and reduce the production cost.

[0058] The depth of the groove 114 close to the intake side 101 is greater than or equal to the depth of the groove 114 close to the exhaust side 102. In this way, on the one hand, it can make the reverse flow of the clearance have a larger flow-through area at the position where the groove 114 is close to the intake side 101. When the reverse flow of the clearance flows from the side of the groove 114 close to the exhaust side 102 to the side of the groove 114 close to the intake side 101, the pressure, flow rate, flow direction, etc. of the air flow change, thereby exciting and forming eddy currents in the air flow. On the other hand, the groove 114 has a larger groove depth close to the intake side 101, and the groove wall on the side of the groove 114 close to the intake side 101 is steeper. When the air flow flows to the groove wall on the side of the groove 114 close to the intake side 101, due to the collision effect of the groove wall, the groove wall guides the flow direction of the air flow, so that the air flow flowing out of the groove 114 intersects and collides with the air flow in the clearance 113 close to the second exhaust member 12, which is beneficial to the formation of eddy currents, and the air flow colliding with the groove wall of the groove 114 is also beneficial to the formation of eddy currents, thereby effectively suppressing the reverse flow of the clearance and improving the air extraction capacity of the exhaust structure 10. Wherein, the depth of the groove 114 refers to the depth of the groove 114 along the protruding direction of the spiral protrusion 111, that is, the depth along the radial direction of the first exhaust member 11, and the radial direction of the first exhaust member 11 is perpendicular to the extension direction of the rotation center line C.

[0059] In some embodiments, the depth of the groove 114 close to the intake side 101 may be equal to the depth of the groove 114 close to the exhaust side 102, or the depth of the groove 114 close to the intake side 101 may also be less than the depth of the groove 114 close to the exhaust side 102. When the gas enters the groove 114 from the clearance 113, the distance between the groove wall of the groove 114 and the side wall of the second exhaust member 12 changes, which is beneficial to forming eddy currents in the air flow, realizing the blocking of the reverse flow of the clearance, and further improving the air extraction capacity of the exhaust structure 10.

[0060] In the direction from the air outlet side 102 to the air inlet side 101 of the exhaust structure 10, the depth of the groove 114 may vary linearly or non-linearly. For example, in the direction from the air outlet side 102 to the air inlet side 101 of the exhaust structure 10, the depth of the groove 114 may increase monotonically. In some embodiments, in the direction from the air outlet side 102 to the air inlet side 101 of the exhaust structure 10, the depth of the groove 114 may first increase and then decrease, first increase and then remain unchanged, etc. In some embodiments, in the direction from the air outlet side 102 to the air inlet side 101 of the exhaust structure 10, the depth of the groove 114 may change in a stepped manner, and the stepped change may be a square stepped change or a smooth stepped change, etc. For example, the depth of the groove 114 may first increase step by step and then decrease step by step, or first increase step by step and then decrease linearly, or first increase linearly and then decrease step by step. In the direction from the air outlet side 102 to the air inlet side 101 of the exhaust structure 10, the change mode of the depth of the groove 114 may be specifically set according to actual needs, and no specific limitation is made in this application. Among them, the direction from the air outlet side 102 to the air inlet side 101 of the exhaust structure 10 is parallel to the extension direction of the rotation center line C.

[0061] The ratio between the depth d1 of the groove 114 and the clearance width d2 between the spiral protrusion 111 and the second exhaust member 12 is 0.5 - 0.75, that is, the ratio between the depth d1 of the groove 114 and the clearance width d2 of the clearance 113 is 0.5 - 0.75. Wherein, the depth d1 of the groove 114 is the maximum depth of the groove 114 along the radial direction of the first exhaust member 11. The clearance width d2 of the clearance 113 is the distance between the surface of the spiral protrusion 111 facing away from the first exhaust member 11 and the surface of the second exhaust member 12 facing the first exhaust member 11. When the ratio between the depth d1 of the groove 114 and the clearance width d2 is 0.5 - 0.75, when the air flow enters the groove 114, it is beneficial for the air flow to separate from the groove wall of the groove 114, and eddy currents are formed in the clearance 113 between the spiral protrusion 111 and the second exhaust member 12, and it is beneficial to increase the intensity and size of the generated eddy currents, and it is beneficial to make the eddy currents excited by the groove 114 close to the middle position of the clearance 113 between the spiral protrusion 111 and the second exhaust member 12, and fully fill the clearance 113 between the spiral protrusion 111 and the second exhaust member 12, thereby being beneficial to improving the blocking effect of the eddy currents on the clearance backflow. When the ratio between the depth d1 of the groove 114 and the clearance width d2 is less than 0.5, the depth of the groove 114 is insufficient, the intensity and size of the eddy currents excited by the groove 114 are insufficient, and it is difficult for the eddy currents to fill the clearance 113, resulting in insufficient inhibitory effect of the eddy currents on the clearance backflow. When the ratio between the depth d1 of the groove 114 and the clearance width d2 is greater than 0.75, the depth of the groove 114 is too large, the separation intensity between the air flow and the groove wall of the groove 114 is insufficient, which is not conducive to the formation of eddy currents, and the intensity and size of the eddy currents are also insufficient after the eddy currents are generated, and the eddy currents will be accommodated in the groove 114, resulting in a large distance between the eddy currents and the side wall of the second exhaust member 12, and the disturbance effect of the eddy currents on the air flow in the clearance 113 is weak, thereby resulting in insufficient inhibitory effect of the eddy currents on the clearance backflow in the clearance 113.

[0062] Wherein, the specific ratio between the depth d1 of the groove 114 and the clearance width d2 of the clearance 113 can be specifically set according to actual needs, and no specific limitation is made in this application. For example, the ratio can be 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.7, 0.71, 0.72, 0.73, 0.74, 0.75, etc.

[0063] In the direction from the intake side 101 to the outlet side 102 of the exhaust structure 10, the ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 is 0.2 - 0.4. Herein, the width w1 of the groove 114 refers to the width at the opening of the groove 114 on the side away from the first exhaust member 11. In this embodiment, the width w1 of the groove 114 and the width w2 of the spiral protrusion 111 may be the widths on a cross-section parallel to the rotation center line C. In some embodiments, the width w1 of the groove 114 and the width w2 of the spiral protrusion 111 may also be the widths on a cross-section perpendicular to the spiral direction of the spiral protrusion 111.

[0064] The ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 being 0.2 - 0.4 is conducive to the separation of the airflow from the groove wall of the groove 114 after the airflow enters the groove 114, enabling the groove 114 to fully disturb the airflow. Thus, it is beneficial for the airflow to form a vortex in the gap 113 between the spiral protrusion 111 and the second exhaust member 12, and is conducive to increasing the intensity and size of the generated vortex, so that the vortex excited and generated by the groove 114 can fully fill the gap 113 between the spiral protrusion 111 and the second exhaust member 12, and block the airflow in the gap 113, thereby enhancing the blocking effect of the vortex on the gap backflow. Additionally, the processing difficulty of the groove 114 can be reduced. When the ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 is less than 0.2, the width proportion of the groove 114 on the spiral protrusion 111 is insufficient. When the airflow flows through the gap 113 between the spiral protrusion 111 and the second exhaust member 12, it is difficult for the groove 114 to excite and generate a vortex that can fully fill the gap 113, and the intensity and size of the generated vortex are insufficient, resulting in insufficient inhibition of the gap backflow by the vortex. When the ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 is greater than 0.4, the width proportion of the groove 114 on the spiral protrusion 111 is too large. When the airflow flows through the groove 114, the separation intensity between the airflow and the groove wall of the groove 114 becomes smaller, which is not conducive to the separation of the airflow from the groove wall of the groove 114 to form a vortex, thus leading to insufficient inhibition of the gap backflow.

[0065] Herein, the specific ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 can be specifically set according to actual needs, and no specific limitation is made in this application. For example, the ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 can be 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, etc.

[0066] In the embodiments of the present application, through the combined action of the ratio between the depth d1 of the middle groove 114 and the gap width d2 of the gap 113 and the ratio between the width w1 of the groove 114 and the width w2 of the spiral protrusion 111 as described above, it is beneficial to generate eddies with sufficient intensity and size in the airflow when the airflow passes through the groove 114, improve the inhibitory effect of the eddies on the gap reverse flow, and improve the air extraction ability of the exhaust structure 10.

[0067] Along the direction from the intake side 101 to the outlet side 102 of the exhaust structure 10, the groove 114 is located between two opposite side surfaces 1111 of the spiral protrusion 111. Among them, the side surface 1111 of the spiral protrusion 111 is connected between the surface of the spiral protrusion 111 facing away from the first exhaust member 11 and the side wall of the first exhaust member 11. In this way, the two opposite side surfaces 1111 of the spiral protrusion 111 are not penetrated by the groove 114, which can avoid increasing the gap width corresponding to the two side surfaces 1111 of the gap 113, and make the gap width at this position the same as the gap width at the position where the groove 114 is not provided in the gap 113, thereby being beneficial to reducing the gas entering the gap 113 and improving the air extraction efficiency of the exhaust structure 10. Among them, along the direction from the intake side 101 to the outlet side 102 of the exhaust structure 10, the groove 114 and the two side surfaces 1111 can be adjacent or spaced apart.

[0068] Please refer to Figure 5 、 Figure 6 and Figure 7 , Figure 6 is a partial cross-sectional view of the exhaust structure 10 provided by the second embodiment of the present application; Figure 7 is a partial cross-sectional view of the exhaust structure 10 provided by the third embodiment of the present application. In some embodiments, the groove 114 can be set to one. In some embodiments, the groove 114 can be set to multiple, and the multiple grooves 114 are arranged side by side along the direction from the intake side 101 to the outlet side 102 of the exhaust structure 10, which can jointly inhibit the gap reverse flow and improve the air extraction ability of the exhaust structure 10. The number of the grooves 114 can be specifically set according to actual needs and is not specifically limited in the present application. For example, the groove 114 can be set to one, two, three, four, five. Among them, when the groove 114 is set to multiple, the adjacent grooves 114 can be spaced apart or adjacent to each other. Among them, when the groove 114 is set to multiple, the widths w1 of different grooves 114 can be set to be the same or different, and the depths d1 of different grooves 114 can be set to be the same or different.

[0069] The shape of the cross section of the groove 114 can be specifically set according to actual needs, and is not specifically limited in the present application. The shape of the cross section of the groove 114 can be a shape along a cross section parallel to the rotation centerline C, or the shape of the cross section of the groove 114 can be a shape on a cross section perpendicular to the spiral direction of the groove 114. The shape of the cross section of the groove 114 can be, but is not limited to, a triangle, a rectangle, an arc, a semi-ellipse, a curved arc, a regular polygon, an irregular polygon, a special shape, etc. When there are multiple grooves 114, the shapes of the cross sections of different grooves 114 can be the same or different.

[0070] See also Figure 5 and Figure 8 , Figure 8 FIG. 1 is a partial cross-sectional view of the exhaust structure 10 provided in the fourth embodiment of the present application. In some embodiments, the cross-sectional shape of the groove 114 can be triangular.

[0071] See also Figure 9 , Figure 9 FIG. 1 is a partial cross-sectional view of the exhaust structure 10 provided in the fifth embodiment of the present application. In some embodiments, the cross-sectional shape of the groove 114 can be rectangular.

[0072] See also Figure 10 , Figure 10 1 is a partial cross-sectional view of the exhaust structure 10 provided in the sixth embodiment of the present application. In some embodiments, the cross-sectional shape of the groove 114 can be an arc shape.

[0073] In some embodiments, the groove wall of the groove 114 close to the air inlet side 101 and the outer side wall of the spiral protrusion 111 facing away from the first exhaust member 11 can be set at an acute angle or a right angle, so that when the airflow flows out of the groove 114 along the groove wall of the groove 114, the flow direction of the airflow is changed, and the airflow is guided to collide with the airflow in the gap 113 close to the second exhaust member 12, so as to form a vortex, increase the intensity and range of the vortex, thereby improving the vortex The inhibitory effect of the gap backflow is improved, and the exhaust capacity of the exhaust structure 10 is improved. In some embodiments, the groove wall of the groove 114 close to the air inlet side 101 and the outer side wall of the spiral protrusion 111 facing away from the first exhaust member 11 can also be set at an obtuse angle to reduce the difficulty of processing the groove 114. Among them, when the groove wall of the groove 114 close to the intake side 101 is constructed as a curved surface, the angle between the groove wall of the groove 114 close to the intake side 101 and the outer side wall of the spiral protrusion 111 facing away from the first exhaust member 11 is the angle between the tangent direction of the connection between the groove wall of the groove 114 close to the intake side 101 and the outer side wall of the spiral protrusion 111 and the outer side wall of the spiral protrusion 111.

[0074] See also Figure 11 , Figure 11It is a developed view of the first exhaust member 11 in the circumferential direction provided in some embodiments of the present application. The circumferential direction of the first exhaust member 11 is the direction around the rotation center line C. In some embodiments, the groove 114 includes a plurality of sub-groove segments 1141. The plurality of sub-groove segments 1141 are sequentially arranged at intervals along the spiral direction of the spiral protrusion 111. Each sub-groove segment 1141 can suppress the backflow of the gap at the corresponding position of the gap 113. Among them, the plurality of sub-groove segments 1141 are arranged in a staggered manner along the extension direction of the rotation center line. On the projection plane perpendicular to the rotation center line C of the first exhaust member 11 and the second exhaust member 12, the orthographic projections of the plurality of sub-groove segments 1141 are connected to form a ring. Thus, through the combined action of the plurality of sub-groove segments 1141, it is possible to suppress the backflow of the gap on the entire circumference of the exhaust structure 10, thereby improving the air extraction ability of the exhaust structure 10. Among them, the extension lengths of different sub-groove segments 1141 can be set to be the same or different. Among the plurality of sub-groove segments 1141, the interval distances between adjacent two sub-groove segments 1141 can be set to be the same or different. The structure of each sub-groove segment 1141 can refer to the description of the groove 114 in the above-mentioned other embodiments, and will not be elaborated here.

[0075] Please refer to Figure 12 , Figure 12 It is a developed view of the first exhaust member 11 in the circumferential direction provided in some other embodiments of the present application. In some embodiments, the plurality of sub-groove segments 1141 can be divided into at least one groove group 1142. When the plurality of sub-groove segments 1141 are divided into a plurality of groove groups 1142, each groove group 1142 includes at least one sub-groove segment 1141. The plurality of groove groups 1142 are arranged at intervals along the circumferential direction of the first exhaust member 11. When each groove group 1142 includes a plurality of sub-groove segments 1141, the plurality of sub-groove segments 1141 in each groove group 1142 are arranged along the extension direction of the rotation center line C. On the projection plane perpendicular to the rotation center line C, the orthographic projection of each groove group 1142 forms an arc segment, that is, on the projection plane perpendicular to the rotation center line C, the orthographic projections of the plurality of sub-groove segments 1141 form at least one arc segment. Thus, through the combined action of the plurality of sub-groove segments 1141 in each groove group 1142, it is possible to suppress the backflow of the gap in the circumferential direction of the exhaust structure 10, thereby improving the air extraction ability of the exhaust structure 10. Among them, the plurality of sub-groove segments 1141 in each groove group 1142 are arranged in alignment along the extension direction of the rotation center line C, or the plurality of sub-groove segments 1141 in each groove group 1142 are arranged in a staggered manner within the range corresponding to the projected arc segment.

[0076] Please refer to Figure 4, the depth of the spiral groove 112 near the intake side 101 can be greater than the depth of the spiral groove 112 near the outlet side 102. The surface of the first exhaust member 11 on the side close to the second exhaust member 12 can be tapered. When the exhaust structure 10 evacuates air, the pressure of the gas gradually increases in the direction from the intake side 101 towards the outlet side 102. The space of the spiral groove 112 near the intake side 101 is larger than the space of the spiral groove 112 near the outlet side 102. When the air flow flows along the spiral groove 112, a pressure gradient can be formed in the spiral groove 112, reducing the gas pressure at the position near the intake side 101 in the spiral groove 112, thereby reducing the pressure difference between the opposite sides of the spiral protrusion 111, and further reducing the gas flow rate flowing into the gap 113 to cooperate with the groove 114 to jointly suppress the gap backflow. In some embodiments, the depth of the spiral groove 112 near the intake side 101 can be equal to the depth of the spiral groove 112 near the outlet side 102.

[0077] Please refer to Figure 13 , Figure 13 is a partial cross-sectional view of the molecular pump 1 provided in some embodiments of the present application. In some embodiments, the first exhaust member 11 can be provided in two. One of the two first exhaust members 11 can be used as the traction stage stator 312 of the traction stage of the molecular pump 1, and the other of the two first exhaust members 11 can be used as the mounting stator 43 of the molecular pump 1. The drive structure 40 is used to be installed inside the mounting stator 43. The second exhaust member 12 is located between the two first exhaust members 11, that is, the second exhaust member 12 is sleeved outside the mounting stator 43, and the traction stage stator 312 is sleeved outside the second exhaust member 12. The second exhaust member 12 is used to rotate relative to the mounting stator 43 and the traction stage stator 312 under the drive of the drive structure 40. Among them, spiral protrusions 111 are respectively provided on the side walls of the two first exhaust members 11 facing the second exhaust member 12, and grooves 114 are provided on the outer side walls of the spiral protrusions 111 facing the second exhaust member 12. The eddy current excited by the groove 114 on the traction stage stator 312 is used to suppress the gap backflow between the traction stage stator 312 and the second exhaust member 12, and the eddy current excited by the groove 114 on the mounting stator 43 is used to suppress the gas from flowing into the drive structure 40.

[0078] Please refer to Figure 14 , Figure 14 is a flow field simulation diagram of the exhaust structure 10 provided in the embodiment of the present application and the exhaust structure in the comparative example. In the exhaust structure 10 provided in the embodiment of the present application, grooves 114 are provided on the spiral protrusions 111, and the ratio of the depth d1 of the groove 114 to the gap width d2 between the spiral protrusion 111 and the second exhaust member 12 is within 0.5 - 0.75, and the ratio of the width w1 of the groove 114 to the width w2 of the spiral protrusion 111 is within 0.2 - 0.4. No grooves are provided on the spiral protrusions in the exhaust structure in the comparative example. From Figure 13As can be seen, in the embodiment of the present application, after a groove 114 is provided on the side of the spiral protrusion 111 close to the second exhaust member 12, when the exhaust structure 10 operates, the leaked air flow in the gap 113 forms a vortex when flowing through the groove 114. The maximum speed of the leaked air flow in the gap 113 decreases from 20 m / s to 12 m / s, and the volume flow rate of the air flow decreases from 0.042 L / s to 0.013 L / s. The overall compression ratio of the exhaust structure 10 increases from 1.25 to 1.43. Therefore, the exhaust structure 10 in the embodiment of the present application can effectively suppress the gap backflow in the gap 113, improve the air extraction capacity of the exhaust structure 10, and improve the vacuum capacity of the molecular pump 1.

[0079] Please refer to Figure 15 , Figure 15 FIG. is a structural block diagram of a process equipment 1000 provided by an embodiment of the present application. Based on the above embodiments, the present application further provides a process equipment 1000. The process equipment 1000 can be applied to the semiconductor technology field. For example, the process equipment 1000 includes but is not limited to semiconductor etching equipment and ion implantation equipment. The process equipment 1000 includes a vacuum chamber 500 and a molecular pump 1 in any one of the above embodiments. The intake port 201 of the molecular pump 1 is used to be connected to the vacuum chamber 500. The vacuum chamber 500 is provided with an air extraction port. The intake port 201 can be directly connected to the air extraction port or connected to the air extraction port through a pipeline. The intake port 201 of the molecular pump 1 is communicated with the intake side 101 of the exhaust structure 10. The molecular pump 1 is used to extract the gas in the vacuum chamber 500 to perform vacuum processing on the vacuum chamber 500. A working device 510 is provided in the vacuum chamber 500. The vacuum chamber 500 is used to provide a vacuum environment required for the operation of the working device 510. In some embodiments, the process equipment 1000 can also be applied to technical fields such as coating, optoelectronic materials, liquid crystal production, vacuum metallurgy, and vacuum degassing.

[0080] In the embodiment of the present application, by providing a groove 114 on the spiral protrusion 111, a vortex is formed when the air flow in the gap 113 flows through the groove 114. The leaked air flow is suppressed by the vortex. Without changing the gap width d2 of the gap 113, that is, without increasing the processing accuracy and assembly difficulty of the molecular pump 1, the sealing performance between the spiral protrusion and the second exhaust member 12 can be improved, the air pumping capacity and pumping efficiency of the exhaust structure 10 can be improved, the vacuum capacity of the molecular pump 1 can be improved, the vacuum performance of the process equipment 1000 can be improved, and the vacuum degree of the vacuum chamber 500 can be improved.

[0081] As described above, it is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An exhaust structure, characterized in that: The exhaust structure is suitable for a molecular pump, and the exhaust structure comprises: a first exhaust member; A second exhaust member, one of the first exhaust member and the second exhaust member is sleeved outside the other, the first exhaust member and the second exhaust member are used for relative rotation, a spiral protrusion is arranged on the side wall of the first exhaust member close to the second exhaust member, the side wall surface of the second exhaust member close to the first exhaust member is a smooth surface, the spiral protrusion is spaced apart from the second exhaust member, and a groove is arranged on the side of the spiral protrusion close to the second exhaust member, and the groove extends along the spiral direction of the spiral protrusion.

2. The exhaust structure according to claim 1, characterized in that: The groove extends at least one circle around a rotation center line of the first exhaust member and the second exhaust member.

3. The exhaust structure according to claim 1 or 2, characterized in that: The exhaust structure has an air inlet side and an air outlet side, and the groove extends from an end of the spiral protrusion close to the air inlet side to an end of the spiral protrusion close to the air outlet side.

4. The exhaust structure according to any one of claims 1 to 3, characterized in that: The groove includes a plurality of sub-groove segments, and the plurality of sub-groove segments are sequentially spaced apart along the spiral direction of the spiral protrusion.

5. The exhaust structure according to claim 4, characterized in that: On a projection plane perpendicular to the rotation center lines of the first exhaust member and the second exhaust member, the orthographic projections of the plurality of sub-groove segments are connected to form a circular ring, or the orthographic projections of the plurality of sub-groove segments form at least one circular arc segment.

6. The exhaust structure according to any one of claims 1 to 5, characterized in that: The exhaust structure has an air inlet side and an air outlet side, and a depth of the groove close to the air inlet side is greater than or equal to a depth of the groove close to the air outlet side.

7. The exhaust structure according to any one of claims 1 to 6, characterized in that: Along the direction from the air inlet side to the air outlet side of the exhaust structure, the groove is located between two opposite side surfaces of the spiral protrusion.

8. The exhaust structure according to any one of claims 1 to 7, characterized in that: Along the direction from the air inlet side to the air outlet side of the exhaust structure, the ratio of the width of the groove to the width of the spiral protrusion is 0.2-0.

4.

9. The exhaust structure according to any one of claims 1 to 8, characterized in that: The ratio of the depth of the groove to the width of the gap between the spiral protrusion and the second exhaust member is 0.5-0.

75.

10. The exhaust structure according to any one of claims 1 to 9, characterized in that: The grooves are provided in plurality, and the plurality of grooves are arranged side by side in a direction from the air inlet side to the air outlet side of the exhaust structure.

11. The exhaust structure according to any one of claims 1 to 10, characterized in that: The spiral protrusion and the first exhaust member are combined to form a spiral groove, and the spiral groove extends along the spiral direction of the spiral protrusion. The exhaust structure has an air inlet side and an air outlet side. The depth of the spiral groove close to the air inlet side is greater than or equal to the depth of the spiral groove close to the air outlet side.

12. A molecular pump, characterized in that: The molecular pump comprises a driving structure such as the exhaust structure according to any one of claims 1 to 11, and the driving structure is drivingly connected to one of the first exhaust component and the second exhaust component.

13. The molecular pump according to claim 12, characterized in that: The exhaust structure is used for the drag stage of the molecular pump.

14. A process equipment, characterized in that: The process equipment comprises a vacuum chamber and a molecular pump as claimed in claim 12 or 13, wherein an air inlet of the molecular pump is connected to the vacuum chamber.

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