Magnetic suspension vacuum pump

Abstract

The invention discloses a magnetic suspension vacuum pump, and relates to the technical field of vacuum pumps. The magnetic suspension vacuum pump comprises a shell, and an impeller, a front bearing seat, a front radial magnetic bearing, a stator, a rear radial magnetic bearing, an axial magnetic bearing and a rotor which are sequentially assembled in the shell, and further comprises a spacer ring, the spacer ring is arranged between the front bearing seat and the front radial magnetic bearing, and a gap communicated with the exterior of the shell is reserved between the spacer ring and the front radial magnetic bearing; a first air inlet cavity is formed; the first flow channel comprises a first air inlet cavity, an air gap between the front radial magnetic bearing and the rotor, an air gap between the stator and the rotor and a first air exhaust cavity. The heat exchange devices are arranged at the two ends of the stator, so that the temperature of the cooling gas can be reduced through the heat exchange devices before the cooling gas passes through the stator, and the problem of local heat accumulation caused by continuous temperature rise in the flowing process of the cooling gas in the shell is avoided.

Description

Technical Field

[0001] This invention relates to the field of vacuum pump technology, specifically to a magnetic levitation vacuum pump. Background Technology

[0002] Magnetic levitation vacuum pumps are industrial equipment that apply magnetic levitation bearing technology to the field of vacuum pumps. By using magnetic levitation bearing technology to replace mechanical contact parts, no lubrication is required, mechanical friction is eliminated, and thus high-precision and high-efficiency vacuum extraction is achieved.

[0003] Magnetic levitation vacuum pumps generate a large amount of heat during operation. Excessive temperature can cause fluctuations in the performance of electromagnetic materials and even lead to winding burnout under high loads. Therefore, heat dissipation is required. In patent application number CN202411206533.5, a magnetic levitation motor and vacuum pump with a thrust plate heat dissipation duct were proposed. The magnetic levitation motor with a thrust plate heat dissipation duct was designed. By setting a thrust plate and heat dissipation duct outside the rotor, the negative pressure is formed by the centrifugal force of rotation, and the external air is drawn in for heat dissipation, which effectively improves the heat dissipation effect of the rear radial magnetic bearing and the axial magnetic bearing.

[0004] However, during the heat dissipation process of this vacuum pump, the temperature of the cooling air will continuously rise after passing through the front radial magnetic bearing and the air gap between the stator and rotor. This reduces the heat dissipation effect on the stator winding located at the air outlet, easily generates heat accumulation, and causes the local temperature to rise. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a magnetic levitation vacuum pump, which solves the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a magnetic levitation vacuum pump, comprising a housing, and an impeller, a front bearing housing, a front radial magnetic bearing, a stator, a rear radial magnetic bearing, an axial magnetic bearing, and a rotor sequentially assembled within the housing; further comprising: a spacer ring disposed between the front bearing housing and the front radial magnetic bearing, with a clearance between the spacer ring and the front radial magnetic bearing communicating with the outside of the housing to form a first air inlet chamber; a clearance between the stator and the rear radial magnetic bearing communicating with the outside of the housing to form a first exhaust chamber; a first flow channel, comprising the first air inlet chamber, an air gap between the front radial magnetic bearing and the rotor, an air gap between the stator and the rotor, and the first exhaust chamber; a water-cooling assembly installed on the inner wall of the housing, wherein a coolant flows through the water-cooling assembly; and a heat exchange device installed on both sides of the stator, with a communication path between the heat exchange device and the water-cooling assembly, so that the coolant flows through the heat exchange device, and the gas in the first flow channel flows through the heat exchange device and exchanges heat with the heat exchange device.

[0007] Furthermore, the heat exchange device includes a first heat exchange component and a second heat exchange component. The first heat exchange component is disposed along the axial direction of the rotor between the front radial magnetic bearing and the stator, and the second heat exchange component is disposed along the axial direction of the rotor between the rear radial magnetic bearing and the stator. The first heat exchange component and the second heat exchange component are symmetrically arranged about the stator.

[0008] Further, the first heat exchange component includes: an outer casing, wherein the inner circumferential side and the side near the stator of the outer casing are open ends, and a predetermined distance is left between them and the outer circumferential surface of the rotor, and the outer circumferential side of the outer casing is a closed end; a heat dissipation plate, wherein the heat dissipation plate is fixed inside the outer casing, dividing the space inside the outer casing into an air inlet side and an air outlet side along the axial direction, and the air inlet side and the air outlet side are connected near the outer circumferential side of the outer casing; and a cooling coil, wherein the cooling coil is fixed inside the heat dissipation plate and is connected to the water cooling component.

[0009] Furthermore, the first heat exchange assembly further includes: a heat sink, the heat sink being U-shaped and sleeved outside the stator winding, one side of the heat sink passing through the side opening of the outer casing and fixed to the heat sink plate, and part of the heat sink being located inside the outer casing and the other part being located outside the outer casing, the number of heat sinks being the same as the number of stator windings, and there being a gap between adjacent heat sinks; the outer casing is provided with an isolation insert on the side near the stator, the isolation insert being able to be inserted into the gap.

[0010] Furthermore, the housing is provided with a rear bearing seat, and a gap is left between the rear bearing seat and the housing to communicate with the outside, so as to form a second air intake chamber. The rear bearing seat is provided with an air passage in the radial direction; a second flow channel, the second flow channel includes the air gap between the rear bearing seat and the axial magnetic bearing and the rotor, the air gap between the rear radial magnetic bearing and the rotor, and the first exhaust chamber.

[0011] Furthermore, the axial magnetic bearing consists of a front axial bearing, a rear axial bearing, and a thrust disk. The front axial bearing is located on the side closer to the rear radial magnetic bearing. A first axial hole is provided on the side of the front axial bearing near its outer circumference. A second axial hole is provided on the side of the thrust disk near the rotor shaft.

[0012] Furthermore, a gap is left between the spacer ring and the front bearing housing to communicate with the outside, so as to form a second exhaust chamber; a cavity is provided between the impeller and the front bearing housing, and a first labyrinth seal structure is provided between the side of the impeller near the outer peripheral surface and the front bearing housing; a flow hole is opened on the front bearing housing, and the cavity and the second exhaust chamber are connected through the flow hole; a third flow channel, the third flow channel includes a first air intake chamber, a gap between the spacer ring and the rotor, a gap between the front bearing housing and the rotor, a cavity, and a second exhaust chamber.

[0013] Furthermore, a flow-blocking ring is provided on the air inlet side of the first heat exchange component, and the flow-blocking ring is fixed on the outer circumferential surface of the rotor; a second labyrinth sealing structure is provided between the flow-blocking ring and the heat sink.

[0014] Furthermore, the water-cooling assembly includes: a first winding tube, which is sleeved on the outer peripheral surface of the front radial magnetic bearing to form a first water-cooling section; a second winding tube, which is sleeved on the outer peripheral surfaces of the rear radial magnetic bearing and the axial magnetic bearing to form a second water-cooling section; a third winding tube and a fourth winding tube, which are both sleeved on the outer peripheral surface of the stator, and one end of the third winding tube is connected to the second winding tube, and one end of the fourth winding tube is connected to the first winding tube.

[0015] Furthermore, the other end of the third winding tube is connected to the water inlet of the first heat exchange component, and the other end of the fourth winding tube is connected to the water inlet of the second heat exchange component.

[0016] The present invention has the following beneficial effects: (1) The magnetic levitation vacuum pump has heat exchange devices at both ends of the stator so that the cooling gas can be cooled down by the heat exchange devices before passing through the stator, thus avoiding the problem of local heat accumulation caused by the continuous increase in temperature of the cooling gas during the flow of the casing.

[0017] (2) The magnetic levitation vacuum pump cools the front radial magnetic bearing, stator, rear radial magnetic bearing and axial magnetic bearing near the outer peripheral surface by setting a water cooling component. At the same time, the water cooling component and the heat exchange device have a connection channel. The heat exchange device has heat dissipation fins that contact the stator winding, so that the coolant in the water cooling component can flow through the heat exchange device, so that the heat exchange device can transfer the heat of the windings at both ends of the stator and carry it away through the water cooling component.

[0018] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a top view of the overall structure of the present invention; Figure 3 This is a schematic cross-sectional view of the internal structure of the present invention; Figure 4 This is a schematic cross-sectional view of the internal structure of the present invention; Figure 5 This is a schematic diagram of the cooling gas flow path of the present invention; Figure 6 For the present invention Figure 3 Enlarged diagram of area A in the middle; Figure 7For the present invention Figure 3 Enlarged diagram of area B in the middle; Figure 8 This is an exploded view of the internal structure of the housing of the present invention; Figure 9 This is a schematic diagram showing the interaction between the heat exchange device and the stator of the present invention; Figure 10 This is an exploded view of the heat exchange device structure of the present invention; Figure 11 This is a cross-sectional schematic diagram of the internal structure of the heat exchange device of the present invention; Figure 12 This is a schematic diagram of the heat sink distribution of the present invention; Figure 13 This is a schematic diagram of the water-cooling component arrangement of the present invention; Figure 14 This is a schematic diagram of the first isolation ring structure of the present invention; Figure 15 This is a schematic diagram of the rear bearing housing structure of the present invention.

[0020] In the diagram, 1. Shell; 2. Impeller; 3. First air inlet; 4. Second air inlet; 5. First exhaust port; 6. Second exhaust port; 7. First water inlet; 8. Second water inlet; 9. First drain port; 10. Second drain port; 13. Front bearing housing; 131. Flow hole; 14. Rotor; 15. Auxiliary bearing; 16. Front radial magnetic bearing; 17. Rear radial magnetic bearing; 18. Axial magnetic bearing; 181. Front axial bearing; 1811. First axial hole; 182. Rear axial bearing; 183. Thrust plate; 1831. Second axial hole; 19. Rear bearing housing; 191. Air passage; 20. First... 21. Heat exchange assembly; 22. Second heat exchange assembly; 23. Outer shell; 24. Heat sink; 25. Cooling coil; 26. Heat sink fin; 27. Isolation fin; 28. First isolation ring; 29. ​​Radial vent; 30. Second isolation ring; 31. Third isolation ring; 32. Fourth isolation ring; 33. Stator; 34. Spacer ring; 35. First labyrinth seal structure; 36. Flow-blocking ring; 37. Second labyrinth seal structure; 38. Flow guide ring; 39. First water inlet end; 40. First water outlet end; 41. Second water inlet end; 42. Second water outlet end; 43. Cavity. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] In the description of this invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "around", etc., which indicate orientation or positional relationship, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this invention.

[0023] The following is based on Figure 1 - Figure 15 This invention describes a magnetic levitation vacuum pump provided in an embodiment of the invention.

[0024] like Figure 1 - Figure 5 As shown, this embodiment of the invention provides a technical solution: a magnetic levitation vacuum pump, including a housing 1, and an impeller 2, a front bearing housing 13, a front radial magnetic bearing 16, a stator 33, a rear radial magnetic bearing 17, an axial magnetic bearing 18, and a rotor 14 sequentially assembled within the housing 1. The front bearing housing 13 is used to install an auxiliary bearing 15, which supports the rotor 14 when power is off. In the prior art, a position sensor (not shown in the figure) should also be provided to determine the position of the rotor 14. The pump also includes a spacer 34, which is disposed between the front bearing housing 13 and the front radial magnetic bearing 16, and a gap is left between the spacer 34 and the front radial magnetic bearing 16 to communicate with the outside of the housing 1, so as to form a first air inlet chamber. A first air inlet 3 is provided on the outer surface of the housing 1, which communicates with the first air inlet chamber to introduce cooling gas into the first air inlet chamber.

[0025] Furthermore, a gap is left between the stator 33 and the rear radial magnetic bearing 17 to communicate with the outside of the housing 1, so as to form a first exhaust chamber. A first exhaust port 5 is provided on the outside of the housing 1, and the cooling gas in the first exhaust chamber can be discharged through the first exhaust port 5.

[0026] Furthermore, a first flow channel for cooling gas circulation is formed within the casing 1, combined with... Figure 5 The first flow channel includes a first air inlet chamber, an air gap between the front radial magnetic bearing 16 and the rotor 14, an air gap between the stator 33 and the rotor 14, and a first exhaust chamber. Since there is a gap between the magnetic poles of the front radial magnetic bearing 16, some of the cooling gas can also flow through the interior of the front radial magnetic bearing 16, thereby carrying away the heat of the front radial magnetic bearing 16 and the stator 33 near the inner circumferential surface through the cooling gas.

[0027] In addition, a water-cooling assembly is provided inside the housing 1. The water-cooling assembly is installed on the inner wall of the housing 1. Coolant is introduced into the water-cooling assembly to cool the front radial magnetic bearing 16, stator 33, rear radial magnetic bearing 17 and axial magnetic bearing 18 on the side near the outer peripheral surface. The coolant can be water or a mixture of water and ethylene glycol.

[0028] Furthermore, heat exchange devices are provided on both sides of the stator 33 inside the housing 1. The heat exchange devices have a communication path with the water cooling assembly so that the coolant flows through the heat exchange devices and the gas in the first flow channel flows through the heat exchange devices and exchanges heat with the heat exchange devices. This allows the cooling gas to carry away some heat through the heat exchange devices before passing through the stator 33, thereby improving the cooling effect of the cooling gas on the side of the stator 33 near the inner circumferential surface.

[0029] like Figure 3 - Figure 5 As shown, the heat exchange device includes a first heat exchange component 20 and a second heat exchange component 21. The first heat exchange component 20 is disposed along the axial direction of the rotor 14 between the front radial magnetic bearing 16 and the stator 33, and there is a gap between it and the front radial magnetic bearing 16 to facilitate the flow of cooling gas. The second heat exchange component 21 is disposed along the axial direction of the rotor 14 between the rear radial magnetic bearing 17 and the stator 33, and there is a gap between it and the rear radial magnetic bearing 17 to facilitate the flow of cooling gas. The first heat exchange component 20 and the second heat exchange component 21 are symmetrically arranged about the stator 33. The first heat exchange component 20 and the second heat exchange component 21 in this scheme have the same composition structure.

[0030] like Figure 3 - Figure 5 as well as Figure 9 - Figure 11 As shown, the first heat exchange assembly 20 includes an outer casing 22. The inner circumferential side and the side near the stator 33 of the outer casing 22 are open ends, and a preset distance is left between them and the outer circumferential surface of the rotor 14. That is, the end face of the outer casing 22 near the rotor 14 does not contact the outer circumferential surface of the rotor 14. Preferably, the preset distance is not less than the air gap between the stator 33 and the outer circumferential surface of the rotor 14. The outer circumferential side of the outer casing 22 is a sealed end, and the outer casing 22 is fixed to the inner wall of the housing 1 through the outer circumferential surface.

[0031] Furthermore, a heat sink 23 is fixed inside the outer casing 22. The heat sink 23 divides the space inside the outer casing 22 into an air inlet side and an air outlet side along the axial direction. The air inlet side and the air outlet side are connected near the outer periphery of the outer casing 22. The cooling gas can contact both sides of the heat sink 23, thereby increasing the contact time between the two and improving the heat exchange effect.

[0032] Furthermore, a cooling coil 24 is provided inside the heat sink 23. The cooling coil 24 is connected to the water cooling component. The coolant in the water cooling component can flow through the cooling coil 24, thereby removing the heat from the heat sink 23.

[0033] like Figure 9 - Figure 12As shown, in order to facilitate heat dissipation of the stator 33 windings, the first heat exchange assembly 20 also includes heat sinks 25. The heat sinks 25 are U-shaped and sleeved on the outside of the stator 33 windings. One side of the heat sink 25 passes through the side opening of the outer casing 22 and is fixed to the heat sink 23. Part of the heat sink 25 is located inside the outer casing 22, and the other part is located outside the outer casing 22. The number of heat sinks 25 is the same as the number of stator 33 windings. There is a gap between adjacent heat sinks 25. The heat generated by the stator 33 windings can be transferred to the heat sink 23 through the heat sinks 25 and dissipated through the water cooling assembly and cooling gas.

[0034] An isolation insert 26 is provided on the side of the outer casing 22 near the stator 33. The isolation insert 26 can be inserted into the gap space, thereby dividing the gap space into two parts along the axial direction. One part is near the heat sink 23 and is formed by the heat sink 23, the outer casing 22, the isolation insert 26 and the heat sink 25. This part is the air outlet side of the outer casing 22. The other part is near the winding of the stator 33 and is formed by the housing 1, the isolation insert 26, the heat sink 25 and the end face of the stator 33. This part is the gap area between the outer casing 22 and the stator 33.

[0035] like Figure 4 and Figure 5 As shown, in order to ensure that the cooling gas in the first flow channel can fully enter the first heat exchange assembly 20, a flow-blocking ring 36 is provided on the air inlet side of the first heat exchange assembly 20. The flow-blocking ring 36 is fixed to the outer peripheral surface of the rotor 14. A second labyrinth seal structure 37 is provided between the flow-blocking ring 36 and the heat sink 23. (Refer to...) Figure 6 and Figure 11 As shown, the second labyrinth sealing structure 37 consists of several sequentially arranged annular sealing teeth. A series of intercepting gaps and expansion cavities are formed between the teeth. When the cooling gas passes through the gaps of the tortuous labyrinth, a throttling effect is generated to achieve the purpose of preventing leakage. This allows the cooling gas in the air gap between the front radial magnetic bearing 16 and the rotor 14 to enter the air inlet side of the first heat exchange assembly 20 and flow out from the air outlet side of the first heat exchange assembly 20, so as to prevent the cooling gas in the air gap between the front radial magnetic bearing 16 and the rotor 14 from directly entering the air gap between the stator 33 and the rotor 14.

[0036] Optionally, combined Figure 14 To prevent some of the cooling gas from entering the gap between the outer casing 22 and the stator 33 after it flows out from the outlet side of the first heat exchange component 20, thus disrupting the airflow, a first isolation ring 27 is provided between the heat sink 23 and the end face of the stator 33 in the first heat exchange component 20. The first isolation ring 27 has radial air holes 271 at the outlet side of the first heat exchange component 20. The end face of the isolation insert 26 here contacts the outer peripheral surface of the first isolation ring 27 to prevent the cooling gas from entering the gap from the side.

[0037] Combination Figure 3 - Figure 6 as well as Figure 7 To facilitate heat dissipation for the axial magnetic bearing 18 and the rear radial magnetic bearing 17, a rear bearing seat 19 is provided inside the housing 1. The rear bearing seat 19 is used to install another auxiliary bearing 15. A gap is left between the rear bearing seat 19 and the housing 1 to communicate with the outside, so as to form a second air intake chamber. The rear bearing seat 19 has an air passage 191 opened radially. A second air inlet 4 is provided outside the housing 1. The second air inlet 4 communicates with the second air intake chamber. Cooling gas can enter the air gap between the rear bearing seat 19 and the rotor 14 through the air passage 191.

[0038] Furthermore, a second flow channel is formed within the shell 1, with the structure as follows: Figure 5 As shown, the second flow channel includes the rear bearing housing 19 and the air gap between the axial magnetic bearing 18 and the rotor 14, the air gap between the rear radial magnetic bearing 17 and the rotor 14, and the first exhaust chamber. Cooling gas enters the second intake chamber from the second intake port 4 and enters the second flow channel through the air passage 191, thereby dissipating heat from the axial magnetic bearing 18 and the rear radial magnetic bearing 17.

[0039] like Figure 7 As shown, the axial magnetic bearing 18 consists of a front axial bearing 181, a rear axial bearing 182, and a thrust disk 183. The front axial bearing 181 is located on the side close to the rear radial magnetic bearing 17. In order to improve the heat dissipation effect of the axial magnetic bearing 18, a first axial hole 1811 is provided on the side of the front axial bearing 181 near the outer peripheral surface, and a second axial hole 1831 is provided on the side of the thrust disk 183 near the axis of the rotor 14. Thus, part of the cooling gas entering from the second air inlet 4 flows directly to the first exhaust chamber through the second axial hole 1831, part of the gas flows through the gap between the thrust disk 183 and the rear axial bearing 182, and then part of the gas flows out through the first axial hole 1811, and part of the gas flows through the gap between the thrust disk 183 and the front axial bearing 181, thereby carrying away the heat inside the axial magnetic bearing 18.

[0040] Combination Figure 4 and Figure 5 When a second heat exchange component 21 is provided, the gap between the second heat exchange component 21 and the end face of the stator 33 is the first exhaust chamber. The cooling gas in the first flow channel flows out from the first exhaust chamber through the air inlet side of the second heat exchange component 21, thereby avoiding excessive heat being carried to the winding on one side of the stator 33.

[0041] Optionally, in order to allow the cooling gas in the first flow channel to fully enter the air intake side of the second heat exchange component 21, a second isolation ring 28 is provided between the end face of the stator 33 and the heat sink 23 of the second heat exchange component 21, so that the first flow channel is not directly connected to the first exhaust chamber.

[0042] Furthermore, the end face of the isolation insert 26 in the second heat exchange assembly 21 is a certain distance from the outer peripheral surface of the second isolation ring 28, so that the cooling gas entering from the inlet side of the second heat exchange assembly 21 first passes through the outlet side of the second heat exchange assembly 21, and then enters the first exhaust chamber from the side of the first exhaust chamber near the rotor 14 and then flows out.

[0043] Optionally, combined Figure 4 and Figure 5 To prevent the cooling gases in the first and second flow channels from directly contacting each other on the outer circumferential surface of the rotor 14, a guide ring 38 is provided on the air inlet side of the second heat exchange assembly 21. The guide ring 38 is fixed on the outer circumferential surface of the rotor 14. The guide ring 38 is used to convert the axial movement of the cooling gases in the first and second flow channels into radial movement, so that they are collected and enter the air inlet side of the second heat exchange assembly 21.

[0044] like Figure 3 , Figure 5 and Figure 6 As shown, in order to dissipate heat from the back of the impeller 2, a gap is left between the spacer ring 34 and the front bearing housing 13 to communicate with the outside, so as to form a second exhaust chamber. The front bearing housing 13 has a protrusion on the side near the rotor 14, and the protrusion contacts the end face of the spacer ring 34 to prevent the cooling gas in the second exhaust chamber from flowing into the air gap between the front bearing housing 13 and the rotor 14.

[0045] Furthermore, a cavity 43 is provided between the impeller 2 and the front bearing housing 13. A first labyrinth seal structure 35 is provided between the side of the impeller 2 near the outer peripheral surface and the front bearing housing 13. The first labyrinth seal structure 35 and the second labyrinth seal structure 37 work on the same principle to isolate the cavity 43 from the front surface of the impeller 2. A flow hole 131 is provided on the front bearing housing 13. The cavity 43 and the second exhaust chamber are connected through the flow hole 131. A second exhaust port 6 is provided on the outside of the housing 1. The cooling gas in the second exhaust chamber is discharged through the second exhaust port 6.

[0046] A third flow channel is also formed inside the shell 1, combined with Figure 5 As shown, the third flow channel includes a first intake chamber, a gap between the partition ring 34 and the rotor 14, a gap between the front bearing housing 13 and the rotor 14, a cavity 43, and a second exhaust chamber. Cooling gas entering from the first intake chamber passes through the third flow channel to achieve heat dissipation on the back side of the impeller 2.

[0047] like Figure 1 - Figure 4 as well as Figure 13 As shown, the above-mentioned water-cooling assembly includes a first winding tube 29, which is sleeved on the outer peripheral surface of the front radial magnetic bearing 16 to form a first water-cooling part, thereby dissipating heat from the outer peripheral surface of the front radial magnetic bearing 16. The end of the first winding tube 29 away from the stator 33 is the first water inlet end 39. A first water inlet 7 is provided on the housing 1, and the first water inlet end 39 is connected to the first water inlet 7.

[0048] Furthermore, a second winding tube 30 is sleeved on the outer peripheral surface of the rear radial magnetic bearing 17 and the axial magnetic bearing 18 to form a second water-cooling section for heat dissipation on the outer peripheral surface of the rear radial magnetic bearing 17 and the axial magnetic bearing 18. The side of the second winding tube 30 away from the stator 33 is the second water inlet end 41. A second water inlet 8 is provided on the housing 1, and the second water inlet end 41 is connected to the second water inlet 8.

[0049] Furthermore, a third winding tube 31 and a fourth winding tube 32 are sleeved on the outer peripheral surface of the stator 33. Preferably, the third winding tube 31 and the fourth winding tube 32 are spirally wound on the outer peripheral surface of the stator 33. One end of the third winding tube 31 is connected to the second winding tube 30, and one end of the fourth winding tube 32 is connected to the first winding tube 29.

[0050] like Figure 1 , Figure 2 and Figure 13 As shown, the other end of the third winding pipe 31 is connected to the water inlet of the first heat exchange component 20, that is, connected to one end of the cooling coil 24 of the first heat exchange component 20. The other end of the cooling coil 24 of the first heat exchange component 20 is the second drain end 42. A second drain port 10 is provided on the housing 1. The second drain end 42 is connected to the second drain port 10. The other end of the fourth winding pipe 32 is connected to the water inlet of the second heat exchange component 21, that is, connected to one end of the cooling coil 24 of the second heat exchange component 21. The other end of the cooling coil 24 of the second heat exchange component 21 is the first drain end 40. A first drain port 9 is provided on the housing 1. The first drain end 40 is connected to the first drain port 9.

[0051] In this embodiment, the flow path of the coolant is divided into two paths. One path flows in from the first inlet 7 and passes through the first inlet end 39, the first winding pipe 29, the fourth winding pipe 32, the first drain end 40, and the first drain outlet 9 in sequence. The other path flows in from the second inlet 8 and passes through the second inlet end 41, the second winding pipe 30, the third winding pipe 31, the second drain end 42, and the second drain outlet 10 in sequence.

[0052] During use (operation), cooling gas is introduced into the first air inlet 3 and the second air inlet 4 respectively. Part of the cooling gas introduced into the first air inlet 3 passes through the third flow channel to dissipate heat on the back side of the impeller 2, and then flows out from the second exhaust chamber. The other part passes through the first flow channel, the first heat exchange component 20 and the second heat exchange component 21, and finally flows out from the first exhaust chamber to dissipate heat on the front radial magnetic bearing 16 and the stator 33, and to exchange heat with the first heat exchange component 20 and the second heat exchange component 21. The cooling gas entering from the second air inlet 4 passes through the second flow channel, the axial magnetic bearing 18, the rear radial magnetic bearing 17 and the second heat exchange component 21, and finally flows out from the first exhaust chamber to dissipate heat on the rear radial magnetic bearing 17, the axial magnetic bearing 18 and the stator 33, and to exchange heat with the second heat exchange component 21.

[0053] Coolant is introduced into the first inlet 7 and the second inlet 8 to cool the front radial magnetic bearing 16, the stator 33, the rear radial magnetic bearing 17 and the axial magnetic bearing 18 on the side near the outer circumference, while the coolant flows through the heat exchange device to carry away the heat.

Claims

1. A magnetic levitation vacuum pump, comprising a housing (1), and an impeller (2), a front bearing housing (13), a front radial magnetic bearing (16), a stator (33), a rear radial magnetic bearing (17), an axial magnetic bearing (18), and a rotor (14) sequentially assembled within the housing (1), characterized in that, Also includes: Spacer (34), the spacer (34) is disposed between the front bearing housing (13) and the front radial magnetic bearing (16), and there is a communication gap between the spacer (34) and the front radial magnetic bearing (16) to the outside of the housing (1) to form a first air intake chamber; A gap is left between the stator (33) and the rear radial magnetic bearing (17) to communicate with the outside of the housing (1) to form a first exhaust chamber; The first flow channel includes a first intake chamber, an air gap between the front radial magnetic bearing (16) and the rotor (14), an air gap between the stator (33) and the rotor (14), and a first exhaust chamber; A water-cooled assembly is installed on the inner wall of the housing (1), and coolant flows through the water-cooled assembly. The heat exchange device is installed on both sides of the stator (33) and has a communication path with the water cooling assembly so that the coolant flows through the heat exchange device and the gas in the first flow channel flows through the heat exchange device and exchanges heat with the heat exchange device.

2. The magnetic levitation vacuum pump according to claim 1, characterized in that: The heat exchange device includes a first heat exchange component (20) and a second heat exchange component (21). The first heat exchange component (20) is disposed between the front radial magnetic bearing (16) and the stator (33) along the axial direction of the rotor (14). The second heat exchange component (21) is disposed between the rear radial magnetic bearing (17) and the stator (33) along the axial direction of the rotor (14). The first heat exchange component (20) and the second heat exchange component (21) are symmetrically arranged about the stator (33).

3. A magnetic levitation vacuum pump according to claim 2, characterized in that, The first heat exchange assembly (20) includes: The outer casing (22) has an open end on its inner circumference side and the side near the stator (33), and a preset distance is left between it and the outer circumference of the rotor (14). The outer circumference side of the outer casing (22) is a closed end. Heat sink (23), the heat sink (23) is fixed inside the outer shell (22), dividing the space inside the outer shell (22) into an air inlet side and an air outlet side along the axial direction, and the air inlet side and the air outlet side are connected near the outer periphery of the outer shell (22); Cooling coil (24) is fixed inside the heat sink (23) and is connected to the water cooling assembly.

4. A magnetic levitation vacuum pump according to claim 3, characterized in that, The first heat exchange assembly (20) further includes: Heat sink (25), the heat sink (25) is U-shaped and sleeved on the outside of the stator (33) winding. One side of the heat sink (25) passes through the side opening of the outer casing (22) and is fixed to the heat sink (23). Part of the heat sink (25) is located inside the outer casing (22) and the other part is located outside the outer casing (22). The number of heat sinks (25) is the same as the number of stator (33) windings. There is a gap between adjacent heat sinks (25). The outer casing (22) is provided with an isolation insert (26) on the side near the stator (33), and the isolation insert (26) can be inserted into the space.

5. A magnetic levitation vacuum pump according to claim 1, characterized in that: The housing (1) is provided with a rear bearing seat (19), and there is a gap between the rear bearing seat (19) and the housing (1) to communicate with the outside, so as to form a second air intake chamber. The rear bearing seat (19) is provided with an air passage (191) in the radial direction. The second flow channel includes the air gap between the rear bearing housing (19) and the axial magnetic bearing (18) and the rotor (14), the air gap between the rear radial magnetic bearing (17) and the rotor (14), and the first exhaust chamber.

6. A magnetic levitation vacuum pump according to claim 5, characterized in that: The axial magnetic bearing (18) consists of a front axial bearing (181), a rear axial bearing (182) and a thrust disk (183), with the front axial bearing (181) located on the side close to the rear radial magnetic bearing (17). The front axial bearing (181) has a first axial hole (1811) on the side near the outer peripheral surface. The thrust disk (183) has a second axial hole (1831) on the side near the axis of the rotor (14).

7. A magnetic levitation vacuum pump according to claim 1, characterized in that: A gap is left between the spacer ring (34) and the front bearing housing (13) to communicate with the outside, so as to form a second exhaust chamber; A cavity (43) is provided between the impeller (2) and the front bearing housing (13). A first labyrinth seal structure (35) is provided between the side of the impeller (2) near the outer circumference and the front bearing housing (13). A flow hole (131) is provided on the front bearing housing (13). The cavity (43) is connected to the second exhaust chamber through the flow hole (131). The third flow channel includes a first intake chamber, a gap between the partition ring (34) and the rotor (14), a gap between the front bearing housing (13) and the rotor (14), a cavity (43), and a second exhaust chamber.

8. A magnetic levitation vacuum pump according to claim 3, characterized in that: The first heat exchange component (20) is provided with a flow-blocking ring (36) on the air inlet side, and the flow-blocking ring (36) is fixed on the outer peripheral surface of the rotor (14); A second labyrinth sealing structure (37) is provided between the flow-blocking ring (36) and the heat sink (23).

9. A magnetic levitation vacuum pump according to claim 3, characterized in that, The water-cooling assembly includes: The first winding tube (29) is sleeved on the outer peripheral surface of the front radial magnetic bearing (16) to form the first water-cooling section; The second winding tube (30) is sleeved on the outer peripheral surface of the rear radial magnetic bearing (17) and the axial magnetic bearing (18) to form a second water-cooled section; The third winding tube (31) and the fourth winding tube (32) are both sleeved on the outer circumferential surface of the stator (33), and one end of the third winding tube (31) is connected to the second winding tube (30), and one end of the fourth winding tube (32) is connected to the first winding tube (29).

10. A magnetic levitation vacuum pump according to claim 9, characterized in that: The other end of the third winding pipe (31) is connected to the water inlet of the first heat exchange component (20), and the other end of the fourth winding pipe (32) is connected to the water inlet of the second heat exchange component (21).

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