Magnetic fluid seal device with rotating water jacket for semiconductor

Abstract

The application discloses a magnetic fluid sealing device with a rotating water jacket for a semiconductor, and aims to solve the problem that the magnetic fluid sealing device is prone to water leakage, thereby affecting other components, especially electrical components. The magnetic fluid sealing device comprises a main shaft and a shell, the shell is fastened to a water jacket, the shell is provided with a mounting hole, the main shaft is rotationally connected to the mounting hole, and a magnetic fluid sealing assembly is arranged between the main shaft and the mounting hole; the main shaft is sleeved to the water jacket, a plurality of sealing rings are arranged between the water jacket and the main shaft in an axial direction, a drainage ring cavity is arranged on the inner wall of the water jacket, and a drainage hole is arranged on the water jacket and communicates with the drainage ring cavity. The sealing performance between the water jacket and the main shaft is good, and the water leakage is not prone to occur; the leaked cooling liquid can flow back to the water return channel, and the water leakage under high speed and high pressure will not affect the safety of external components, so that the safe operation of the whole device is ensured.

Description

Technical Field

[0001] This invention relates to a magnetohydrodynamic sealing device, and more specifically, to a magnetohydrodynamic sealing device with a rotating water jacket for semiconductor applications. Background Technology

[0002] Magnetofluidic seals are widely used due to their reliable sealing, leak-free operation, minimal mechanical wear, and long service life, as exemplified by the high-pressure magnetofluidic seal device disclosed in Chinese Patent Application No. 2026103812475. In this device, a water jacket fixed externally to the magnetofluidic seal allows semiconductor process fluid to be introduced into a rotating spindle. The fluid then enters the process components within the semiconductor cavity through the spindle, simultaneously sealing both liquid and gas. The inlet and outlet water pipes on the water jacket are sealed to the rotating spindle via sealing rings. External cooling fluid enters the rotating spindle through the inlet pipe and then flows into the process components within the vacuum cavity through a channel on the spindle. The maximum rotational linear speed between the water jacket and the rotating spindle, sealed by the sealing rings, does not exceed 5 m / s, making it unsuitable for applications with higher rotational speeds. Leakage is prone to occur during use, potentially affecting other components, especially electrical components, and thus impacting the safe operation of the entire equipment. Summary of the Invention

[0003] To overcome the above shortcomings, the present invention provides a magnetic fluid sealing device with a rotating water jacket for semiconductors. The water jacket and the rotating spindle have good sealing performance and are not prone to water leakage. The leaked coolant can flow back into the return water channel. Even if water leakage occurs under high speed and high pressure, it will not leak outside the flow channel and affect the safety of external components, thus ensuring the safe operation of the entire equipment.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a magnetic fluid sealing device with a rotating water jacket for semiconductors, comprising a main shaft and a housing, the housing being fastened to the water jacket, the housing being provided with a mounting hole, the main shaft being rotatably connected to the mounting hole, and a magnetic fluid sealing assembly being installed between the main shaft and the mounting hole; the main shaft and the water jacket being fitted together, and multiple sealing rings being axially spaced between the water jacket and the main shaft, a drain ring cavity being provided on the inner wall of the water jacket, and a drain hole communicating with the drain ring cavity being provided on the water jacket.

[0005] During spindle rotation, a magnetic fluid seal is achieved between the spindle and the housing via a magnetic fluid sealing assembly, providing excellent sealing performance. The spindle and water jacket are sealed by multiple axially spaced sealing rings, ensuring a good seal and minimizing leakage. A drain ring cavity is provided on the inner wall of the water jacket. Liquid seeping from the inner wall of the water jacket collects in the drain ring cavity and is discharged through the drain hole back into the return water channel, preventing leakage from affecting the safety of external components.

[0006] The magnetic fluid sealing device with rotating water jacket for semiconductors described in this application has good sealing performance between the water jacket and the spindle, making it less prone to water leakage. The leaked coolant can flow back into the return water channel. Even if leakage occurs under high speed and high pressure, it will not leak outside the flow channel and affect the safety of external components, thus ensuring the safe operation of the entire equipment.

[0007] Preferably, the sealing ring includes an elastomer and an O-ring, with the O-ring disposed on the outer wall of the elastomer.

[0008] The elastomer is made of wear-resistant materials, such as PTFE. The elastomer is in direct contact with the spindle, resulting in a long service life. The O-ring is machined from FKM or FFKM and forms a static seal with the water jacket, providing excellent sealing. This structure allows for a sealing ring linear velocity of up to 15 m / s, meeting the requirements of semiconductor equipment applications.

[0009] Preferably, a number of sealing teeth are axially spaced on the inner wall of the elastic body.

[0010] Sealing teeth are provided on the inner wall of the elastomer to improve the sealing performance between the elastomer and the spindle.

[0011] Preferably, the inner wall of the water jacket is provided with an inlet ring cavity and an outlet ring cavity, the main shaft is provided with an inlet hole and an outlet hole, the inlet hole is connected to the inlet ring cavity, the outlet hole is connected to the outlet ring cavity, and the water jacket is provided with an inlet nozzle connected to the inlet ring cavity and an outlet nozzle connected to the outlet ring cavity.

[0012] Cooling water enters the inlet ring cavity through the inlet nozzle, and after passing through the inlet hole, it enters the process components of the vacuum chamber. Then, the cooling water flows through the outlet hole to the outlet ring cavity, and finally is discharged outward from the outlet nozzle.

[0013] Preferably, two drainage ring cavities are provided, with the inlet ring cavity and the outlet ring cavity both located between the two drainage ring cavities. A flow passage is provided inside the water jacket, and the two drainage ring cavities and the drainage hole are all connected to the flow passage.

[0014] Both the inlet and outlet ring cavities are located between the two drain ring cavities to ensure that leaked cooling water can be collected in the drain ring cavity and discharged from the drain hole.

[0015] Preferably, an air intake channel is provided on the outer casing, and a ventilation annular cavity is formed between the inner wall of the mounting hole and the outer wall of the main shaft. A ventilation hole is provided inside the main shaft, and the ventilation hole communicates with the ventilation annular cavity.

[0016] The process components are supplied with air through the air intake channel into the ventilation ring cavity and then through the ventilation hole into the vacuum cavity.

[0017] Preferably, the magnetofluid sealing assembly includes two sets of magnetofluid units, with a support ring between the two magnetofluid units. Each magnetofluid unit includes two magnetic poles and a magnetic block disposed between the two magnetic poles. A retaining ring is installed inside the mounting ring, and the retaining ring axially positions the magnetofluid unit. Magnetic fluid is loaded between the inner wall of the magnetic poles and the outer wall of the main shaft.

[0018] A magnetic block is installed between two magnetic poles to create a magnetic field. The magnetic fluid is sealed between the outer wall of the spindle and the inner wall of the magnetic pole under the action of the magnetic field, resulting in a good sealing effect. A retaining ring axially positions the magnetic fluid unit, ensuring reliable installation of the magnetic fluid unit.

[0019] Preferably, a number of sealing ring grooves corresponding to the magnetic poles are provided at intervals on the outer wall of the main shaft, and the magnetic fluid is loaded in the sealing ring grooves.

[0020] The sealing ring groove facilitates the loading of magnetic fluid and prevents the magnetic fluid from detaching from the inner wall of the magnetic pole.

[0021] Preferably, a DLC coating is provided on the outer wall of the spindle.

[0022] By applying a DLC coating to the outer wall of the spindle, the surface hardness of the spindle reaches HRC50 or higher, while the surface roughness reaches RA0.02. The DLC coating also has a self-lubricating effect, which improves the wear resistance of the spindle and ensures the smooth rotation of the spindle.

[0023] Preferably, the outer casing is provided with an outwardly extending connecting plate, which is tightly connected to the semiconductor vacuum chamber.

[0024] The connection plate on the outer casing facilitates connection with the semiconductor vacuum chamber.

[0025] Compared with the prior art, the beneficial effects of the present invention are: (1) The water jacket and the main shaft are sealed by multiple sealing rings installed at axial intervals, which has good sealing performance and is not prone to water leakage; (2) Even if water leakage occurs under high speed and high pressure, the leaked coolant can flow back into the return water channel and will not leak out of the flow channel and affect the safety of external components, thereby ensuring the safe operation of the entire equipment; (3) A DLC coating is provided on the outer wall of the main shaft, so that the surface hardness of the main shaft reaches HRC50 or above, and the surface roughness of the main shaft reaches RA0.02. The DLC coating has a self-lubricating effect, which improves the wear resistance of the main shaft and ensures the smooth rotation of the main shaft. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the present invention.

[0027] Figure 2 This is a structural diagram of the present invention in use.

[0028] Figure 3 This is a diagram of the water jacket connection structure of Embodiment 1 of the present invention.

[0029] Figure 4 This is a structural diagram of the sealing ring of the present invention.

[0030] Figure 5 This is a structural diagram of the main shaft of the present invention.

[0031] Figure 6 This is a structural diagram of the magnetohydrodynamic sealing assembly of the present invention.

[0032] Figure 7 This is a diagram of the water jacket connection structure of Embodiment 2 of the present invention.

[0033] Figure 8 This is a diagram of the water jacket connection structure of Embodiment 3 of the present invention.

[0034] In the diagram: 1. Spindle, 2. Housing, 3. Water jacket, 4. Mounting ring groove, 5. Positioning convex ring, 6. Mounting hole, 7. Bearing, 8. Limiting ring, 9. Bearing ring, 10. Magnetofluid unit, 11. Support ring, 12. Magnetic pole, 13. Magnetic block, 14. Retaining ring, 15. Magnetic fluid, 16. Sealing ring groove, 17. Sealing ring, 18. Elastomer, 19. O-ring, 20. Receiving ring groove, 21. Sealing tooth, 22. 23. Drainage ring cavity, 24. Drainage hole, 25. Water inlet ring cavity, 26. Water outlet ring cavity, 27. Water inlet hole, 28. Water inlet nozzle, 29. Water outlet nozzle, 30. Flow passage, 31. Sealing plug, 32. Air inlet passage, 33. Ventilation ring cavity, 34. Ventilation hole, 35. Transition hole, 36. Connecting hole, 37. Connecting plate, 38. Liquid outlet hole, 39. Leakage hole, 40. Heat dissipation groove, 41. Heat dissipation hole. Detailed Implementation

[0035] The technical solution of the present invention will be further described in detail below through specific embodiments and with reference to the accompanying drawings: Example 1: A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors (see...) Figures 1 to 6 The system includes a main shaft 1 and a housing 2. The housing 2 is fastened to a water jacket 3. A mounting groove 4 is provided on the end face of the housing 2, and a positioning protrusion 5 is provided on the end face of the water jacket 3. The positioning protrusion 5 is fitted into the mounting groove 4. The water jacket 3 and the housing 2 are fastened together by screws. A mounting hole 6 is provided on the housing 2. The main shaft 1 is rotatably connected to the mounting hole 6. Bearings 7 are installed between the two ends of the mounting hole 6 and the main shaft 1. A stepped surface is provided at the front end of the mounting hole 6. The outer ring of the front bearing 7 rests on the stepped surface. Two limiting rings 8 are installed on the main shaft 1. The two ends of the inner ring of the front bearing 7 abut against the two limiting rings 8 for positioning. A bearing ring 9 is fastened to the rear end of the mounting hole 6. The bearing ring 9 rests on the outer ring end face of the rear bearing 7.

[0036] A magnetic fluid sealing assembly is installed between the spindle 1 and the mounting hole 6. The magnetic fluid sealing assembly includes two sets of magnetic fluid units 10, with a support ring 11 between the two magnetic fluid units 10. Each magnetic fluid unit 10 includes two magnetic poles 12 and a magnetic block 13 disposed between the two magnetic poles 12. A sealing ring is installed between the outer wall of the magnetic pole 12 and the inner wall of the mounting hole 6. A retaining ring 14 is installed inside the mounting ring, axially positioning the magnetic fluid unit 10. Magnetic fluid 15 is loaded between the inner wall of the magnetic pole 12 and the outer wall of the spindle 1. One retaining ring 14 is installed at the front and one at the rear, thus axially limiting the two sets of magnetic fluid units 10 between the two retaining rings 14. The magnetic block 13, installed between the two magnetic poles 12, forms a magnetic field. The magnetic fluid 15, under the action of the magnetic field, is sealed between the outer wall of the spindle 1 and the inner wall of the magnetic pole 12, resulting in a good sealing effect. The retaining ring 14 axially positions the magnetic fluid unit 10, ensuring reliable installation of the magnetic fluid unit 10. Several sealing ring grooves 16, corresponding to the magnetic poles 12, are spaced apart on the outer wall of the main shaft 1. The magnetic fluid 15 is loaded in the sealing ring grooves 16. Each magnetic pole 12 is provided with several sealing ring grooves 16, which provide a space for the magnetic fluid 15 and prevent the magnetic fluid 15 from detaching from the magnetic pole 12.

[0037] The main shaft 1 is connected to the water jacket 3. Multiple sealing rings 17 are axially spaced between the water jacket 3 and the main shaft 1. Each sealing ring 17 includes an elastomer 18 and an O-ring 19, with the O-ring 19 positioned on the outer wall of the elastomer 18. A receiving ring groove 20 corresponding to the sealing ring 17 is provided on the inner wall of the water jacket 3. The sealing ring 17 is fitted into the receiving ring groove 20, and the O-ring 19 abuts against the bottom surface of the receiving ring groove 20. The elastomer 18 is fitted to the outer wall of the main shaft 1. The elastomer 18 is made of a wear-resistant material, such as PTFE. The elastomer 18 is in direct contact with the main shaft 1, resulting in a long service life. The O-ring 19 is made of FKM or FFKM, forming a static seal with the water jacket 3, providing excellent sealing performance. Several sealing teeth 21 are axially spaced on the inner wall of the elastomer 18, improving the sealing performance between the elastomer 18 and the main shaft 1.

[0038] A DLC coating is applied to the outer wall of the spindle 1. By applying the DLC coating to the outer wall of the spindle 1, the surface hardness of the spindle 1 reaches HRC50 or higher, and the surface roughness of the spindle 1 reaches RA0.02. In addition, the DLC coating has a self-lubricating effect, which improves the wear resistance of the spindle 1 and ensures the smooth rotation of the spindle 1.

[0039] A drainage annular cavity 22 is provided on the inner wall of the water jacket 3, and a drainage hole 23 communicating with the drainage annular cavity 22 is provided on the water jacket 3. An inlet annular cavity 24 and an outlet annular cavity 25 are provided on the inner wall of the water jacket 3. An inlet hole 26 and an outlet hole 27 are provided inside the main shaft 1. The inlet hole 26 and the outlet hole 27 are parallel to the axis of the main shaft 1. The inlet hole 26 communicates with the inlet annular cavity 24, and the outlet hole 27 is connected to the outlet annular cavity 25. An inlet nozzle 28 communicating with the inlet annular cavity 24 and an outlet nozzle 29 communicating with the outlet annular cavity 25 are provided on the water jacket 3. A hole is drilled on the bottom surface of the inlet annular cavity 24 communicating with the inlet nozzle 28, and a hole is drilled on the bottom surface of the outlet annular cavity 25 communicating with the outlet nozzle 29. Holes are drilled at corresponding positions at the ends of the inlet hole 26 and the outlet hole 27 on the outer wall of the main shaft 1, respectively, communicating with the inlet hole 26 and the outlet hole 27.

[0040] The inlet annular cavity 24 and the outlet annular cavity 25 are axially offset. Two drainage annular cavities 22 are provided, with both the inlet annular cavity 24 and the outlet annular cavity 25 located between the two drainage annular cavities 22. A flow passage 30 is provided inside the water jacket 3, and the two drainage annular cavities 22 and the drainage hole 23 are all connected to the flow passage 30. Sealing rings 17 are installed on both sides of the inlet annular cavity 24, both sides of the outlet annular cavity 25, and both sides of the drainage annular cavity 22. The flow passage 30 is parallel to the axis of the water jacket 3. A hole is drilled at the outer end of the water jacket 3 to form the flow passage 30, and a sealing plug 31 is connected to the outer end of the flow passage 30. A hole is drilled at the bottom of the drainage annular cavity 22 and connected to the flow passage 30.

[0041] An air intake channel 32 is provided on the outer casing 2. A ventilation annular cavity 33 is formed between the inner wall of the mounting hole 6 and the outer wall of the main shaft 1. A ventilation hole 34 is provided inside the main shaft 1, and the ventilation hole 34 communicates with the ventilation annular cavity 33. The ventilation hole 34 is coaxially arranged with the main shaft 1. The ventilation annular cavity 33 is located on the inner wall of the support ring 11. A transition hole 35 is provided on the support ring 11, and the transition hole 35 connects the ventilation annular cavity 33 and the air intake channel 32. A connecting hole 36 is drilled at the corresponding end of the ventilation hole 34 on the outer wall of the main shaft 1. The connecting hole 36 is offset from the water inlet hole 26 and the water outlet hole 27, and the connecting hole 36 connects the ventilation annular cavity 33 and the ventilation hole 34.

[0042] An outwardly extending connecting plate 37 is provided on the outer casing 2, and the connecting plate 37 is tightly connected to the semiconductor vacuum chamber. A sealing ring is installed between the connecting plate 37 and the semiconductor vacuum chamber.

[0043] During the rotation of the main shaft 1, a magnetic fluid seal is achieved between the main shaft 1 and the outer casing 2 through a magnetic fluid sealing assembly, resulting in a good sealing effect. The main shaft 1 and the water jacket 3 are sealed by multiple axially spaced sealing rings 17. The elastic body 18 of the sealing ring 17 directly contacts the main shaft 1, exhibiting high temperature resistance, wear resistance, and a long service life. The O-rings 19 of the sealing rings 17 and the water jacket 3 form a static seal, providing a good sealing effect and minimizing leakage. A drain ring cavity 22 is provided on the inner wall of the water jacket 3. Liquid seeping from the inner wall of the water jacket 3 collects in the drain ring cavity 22 and is discharged through the drain hole 23 back into the return water channel, preventing leakage from affecting the safety of external components.

[0044] The magnetic fluid sealing device with rotating water jacket 3 used in this application for semiconductors has good sealing performance between the water jacket 3 and the spindle 1, making it less prone to water leakage. The leaked coolant can flow back into the return water channel. Even if leakage occurs under high speed and high pressure, it will not leak outside the flow channel and affect the safety of external components, thus ensuring the safe operation of the entire equipment.

[0045] Example 2: A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors (see...) Figure 7 The system includes a main shaft 1 and a housing 2. The housing 2 is fastened to a water jacket 3. A mounting groove 4 is provided on the end face of the housing 2, and a positioning protrusion 5 is provided on the end face of the water jacket 3. The positioning protrusion 5 is fitted into the mounting groove 4. The water jacket 3 and the housing 2 are fastened together by screws. A mounting hole 6 is provided on the housing 2. The main shaft 1 is rotatably connected to the mounting hole 6. Bearings 7 are installed between the two ends of the mounting hole 6 and the main shaft 1. A stepped surface is provided at the front end of the mounting hole 6. The outer ring of the front bearing 7 rests on the stepped surface. Two limiting rings 8 are installed on the main shaft 1. The two ends of the inner ring of the front bearing 7 abut against the two limiting rings 8 for positioning. A bearing ring 9 is fastened to the rear end of the mounting hole 6. The bearing ring 9 rests on the outer ring end face of the rear bearing 7.

[0046] A magnetic fluid sealing assembly is installed between the spindle 1 and the mounting hole 6. The magnetic fluid sealing assembly includes two sets of magnetic fluid units 10, with a support ring 11 between the two magnetic fluid units 10. Each magnetic fluid unit 10 includes two magnetic poles 12 and a magnetic block 13 disposed between the two magnetic poles 12. A sealing ring is installed between the outer wall of the magnetic pole 12 and the inner wall of the mounting hole 6. A retaining ring 14 is installed inside the mounting ring, axially positioning the magnetic fluid unit 10. Magnetic fluid 15 is loaded between the inner wall of the magnetic pole 12 and the outer wall of the spindle 1. One retaining ring 14 is installed at the front and one at the rear, thus axially limiting the two sets of magnetic fluid units 10 between the two retaining rings 14. The magnetic block 13, installed between the two magnetic poles 12, forms a magnetic field. The magnetic fluid 15, under the action of the magnetic field, is sealed between the outer wall of the spindle 1 and the inner wall of the magnetic pole 12, resulting in a good sealing effect. The retaining ring 14 axially positions the magnetic fluid unit 10, ensuring reliable installation of the magnetic fluid unit 10. Several sealing ring grooves 16, corresponding to the magnetic poles 12, are spaced apart on the outer wall of the main shaft 1. The magnetic fluid 15 is loaded in the sealing ring grooves 16. Each magnetic pole 12 is provided with several sealing ring grooves 16, which provide a space for the magnetic fluid 15 and prevent the magnetic fluid 15 from detaching from the magnetic pole 12.

[0047] The main shaft 1 is connected to the water jacket 3. Multiple sealing rings 17 are axially spaced between the water jacket 3 and the main shaft 1. Each sealing ring 17 includes an elastomer 18 and an O-ring 19, with the O-ring 19 positioned on the outer wall of the elastomer 18. A receiving ring groove 20 corresponding to the sealing ring 17 is provided on the inner wall of the water jacket 3. The sealing ring 17 is fitted into the receiving ring groove 20, and the O-ring 19 abuts against the bottom surface of the receiving ring groove 20. The elastomer 18 is fitted to the outer wall of the main shaft 1. The elastomer 18 is made of a wear-resistant material, such as PTFE. The elastomer 18 is in direct contact with the main shaft 1, resulting in a long service life. The O-ring 19 is made of FKM or FFKM, forming a static seal with the water jacket 3, providing excellent sealing performance. Several sealing teeth 21 are axially spaced on the inner wall of the elastomer 18, improving the sealing performance between the elastomer 18 and the main shaft 1.

[0048] A DLC coating is applied to the outer wall of the spindle 1. By applying the DLC coating to the outer wall of the spindle 1, the surface hardness of the spindle 1 reaches HRC50 or higher, and the surface roughness of the spindle 1 reaches RA0.02. In addition, the DLC coating has a self-lubricating effect, which improves the wear resistance of the spindle 1 and ensures the smooth rotation of the spindle 1.

[0049] A drainage annular cavity 22 is provided on the inner wall of the water jacket 3, and a drainage hole 23 communicating with the drainage annular cavity 22 is provided on the water jacket 3. An inlet annular cavity 24 and an outlet annular cavity 25 are provided on the inner wall of the water jacket 3. An inlet hole 26 and an outlet hole 27 are provided inside the main shaft 1. The inlet hole 26 and the outlet hole 27 are parallel to the axis of the main shaft 1. The inlet hole 26 communicates with the inlet annular cavity 24, and the outlet hole 27 is connected to the outlet annular cavity 25. An inlet nozzle 28 communicating with the inlet annular cavity 24 and an outlet nozzle 29 communicating with the outlet annular cavity 25 are provided on the water jacket 3. A hole is drilled on the bottom surface of the inlet annular cavity 24 communicating with the inlet nozzle 28, and a hole is drilled on the bottom surface of the outlet annular cavity 25 communicating with the outlet nozzle 29. Holes are drilled at corresponding positions at the ends of the inlet hole 26 and the outlet hole 27 on the outer wall of the main shaft 1, respectively, communicating with the inlet hole 26 and the outlet hole 27.

[0050] The inlet annular cavity 24 and the outlet annular cavity 25 are axially offset. Two drainage annular cavities 22 are provided, with both the inlet annular cavity 24 and the outlet annular cavity 25 located between the two drainage annular cavities 22. A flow passage 30 is provided inside the water jacket 3, and the two drainage annular cavities 22 and the drainage hole 23 are all connected to the flow passage 30. Sealing rings 17 are installed on both sides of the inlet annular cavity 24, both sides of the outlet annular cavity 25, and both sides of the drainage annular cavity 22. The flow passage 30 is parallel to the axis of the water jacket 3. A hole is drilled at the outer end of the water jacket 3 to form the flow passage 30, and a sealing plug 31 is connected to the outer end of the flow passage 30. A hole is drilled at the bottom of the drainage annular cavity 22 and connected to the flow passage 30.

[0051] A liquid outlet hole 38 is provided between the bottom of the drain ring cavity 22 and the flow channel 30. The receiving ring groove 20 on both sides of the liquid outlet hole 38 is connected to the liquid outlet hole 38 via a seepage hole 39 near the bottom. When coolant seeps out, the coolant can flow into the receiving ring groove 20 along the seepage hole 39 to cool the sealing ring 17, reduce the temperature of the sealing ring 17, and help slow down the wear of the sealing ring 17 and extend its service life.

[0052] An air intake channel 32 is provided on the outer casing 2. A ventilation annular cavity 33 is formed between the inner wall of the mounting hole 6 and the outer wall of the main shaft 1. A ventilation hole 34 is provided inside the main shaft 1, and the ventilation hole 34 communicates with the ventilation annular cavity 33. The ventilation hole 34 is coaxially arranged with the main shaft 1. The ventilation annular cavity 33 is located on the inner wall of the support ring 11. A transition hole 35 is provided on the support ring 11, and the transition hole 35 connects the ventilation annular cavity 33 and the air intake channel 32. A connecting hole 36 is drilled at the corresponding end of the ventilation hole 34 on the outer wall of the main shaft 1. The connecting hole 36 is offset from the water inlet hole 26 and the water outlet hole 27, and the connecting hole 36 connects the ventilation annular cavity 33 and the ventilation hole 34.

[0053] An outwardly extending connecting plate 37 is provided on the outer casing 2, and the connecting plate 37 is tightly connected to the semiconductor vacuum chamber. A sealing ring is installed between the connecting plate 37 and the semiconductor vacuum chamber.

[0054] During the rotation of the main shaft 1, a magnetic fluid seal is achieved between the main shaft 1 and the outer casing 2 through a magnetic fluid sealing assembly, resulting in a good sealing effect. The main shaft 1 and the water jacket 3 are sealed by multiple axially spaced sealing rings 17. The elastic body 18 of the sealing ring 17 directly contacts the main shaft 1, exhibiting high temperature resistance, wear resistance, and a long service life. The O-rings 19 of the sealing rings 17 and the water jacket 3 form a static seal, providing a good sealing effect and minimizing leakage. A drain ring cavity 22 is provided on the inner wall of the water jacket 3. Liquid seeping from the inner wall of the water jacket 3 collects in the drain ring cavity 22 and is discharged through the drain hole 23 back into the return water channel, preventing leakage from affecting the safety of external components.

[0055] The magnetic fluid sealing device with rotating water jacket 3 used in this application for semiconductors has good sealing performance between the water jacket 3 and the spindle 1, making it less prone to water leakage. The leaked coolant can flow back into the return water channel. Even if leakage occurs under high speed and high pressure, it will not leak outside the flow channel and affect the safety of external components, thus ensuring the safe operation of the entire equipment.

[0056] Example 3: A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors (see...) Figure 8 The system includes a main shaft 1 and a housing 2. The housing 2 is fastened to a water jacket 3. A mounting groove 4 is provided on the end face of the housing 2, and a positioning protrusion 5 is provided on the end face of the water jacket 3. The positioning protrusion 5 is fitted into the mounting groove 4. The water jacket 3 and the housing 2 are fastened together by screws. A mounting hole 6 is provided on the housing 2. The main shaft 1 is rotatably connected to the mounting hole 6. Bearings 7 are installed between the two ends of the mounting hole 6 and the main shaft 1. A stepped surface is provided at the front end of the mounting hole 6. The outer ring of the front bearing 7 rests on the stepped surface. Two limiting rings 8 are installed on the main shaft 1. The two ends of the inner ring of the front bearing 7 abut against the two limiting rings 8 for positioning. A bearing ring 9 is fastened to the rear end of the mounting hole 6. The bearing ring 9 rests on the outer ring end face of the rear bearing 7.

[0057] A magnetic fluid sealing assembly is installed between the spindle 1 and the mounting hole 6. The magnetic fluid sealing assembly includes two sets of magnetic fluid units 10, with a support ring 11 between the two magnetic fluid units 10. Each magnetic fluid unit 10 includes two magnetic poles 12 and a magnetic block 13 disposed between the two magnetic poles 12. A sealing ring is installed between the outer wall of the magnetic pole 12 and the inner wall of the mounting hole 6. A retaining ring 14 is installed inside the mounting ring, axially positioning the magnetic fluid unit 10. Magnetic fluid 15 is loaded between the inner wall of the magnetic pole 12 and the outer wall of the spindle 1. One retaining ring 14 is installed at the front and one at the rear, thus axially limiting the two sets of magnetic fluid units 10 between the two retaining rings 14. The magnetic block 13, installed between the two magnetic poles 12, forms a magnetic field. The magnetic fluid 15, under the action of the magnetic field, is sealed between the outer wall of the spindle 1 and the inner wall of the magnetic pole 12, resulting in a good sealing effect. The retaining ring 14 axially positions the magnetic fluid unit 10, ensuring reliable installation of the magnetic fluid unit 10. Several sealing ring grooves 16, corresponding to the magnetic poles 12, are spaced apart on the outer wall of the main shaft 1. The magnetic fluid 15 is loaded in the sealing ring grooves 16. Each magnetic pole 12 is provided with several sealing ring grooves 16, which provide a space for the magnetic fluid 15 and prevent the magnetic fluid 15 from detaching from the magnetic pole 12.

[0058] The main shaft 1 is connected to the water jacket 3. Multiple sealing rings 17 are axially spaced between the water jacket 3 and the main shaft 1. Each sealing ring 17 includes an elastomer 18 and an O-ring 19, with the O-ring 19 positioned on the outer wall of the elastomer 18. A receiving ring groove 20 corresponding to the sealing ring 17 is provided on the inner wall of the water jacket 3. The sealing ring 17 is fitted into the receiving ring groove 20, and the O-ring 19 abuts against the bottom surface of the receiving ring groove 20. The elastomer 18 is fitted to the outer wall of the main shaft 1. The elastomer 18 is made of a wear-resistant material, such as PTFE. The elastomer 18 is in direct contact with the main shaft 1, resulting in a long service life. The O-ring 19 is made of FKM or FFKM, forming a static seal with the water jacket 3, providing excellent sealing performance. Several sealing teeth 21 are axially spaced on the inner wall of the elastomer 18, improving the sealing performance between the elastomer 18 and the main shaft 1.

[0059] A DLC coating is applied to the outer wall of the spindle 1. By applying the DLC coating to the outer wall of the spindle 1, the surface hardness of the spindle 1 reaches HRC50 or higher, and the surface roughness of the spindle 1 reaches RA0.02. In addition, the DLC coating has a self-lubricating effect, which improves the wear resistance of the spindle 1 and ensures the smooth rotation of the spindle 1.

[0060] A drainage annular cavity 22 is provided on the inner wall of the water jacket 3, and a drainage hole 23 communicating with the drainage annular cavity 22 is provided on the water jacket 3. An inlet annular cavity 24 and an outlet annular cavity 25 are provided on the inner wall of the water jacket 3. An inlet hole 26 and an outlet hole 27 are provided inside the main shaft 1. The inlet hole 26 and the outlet hole 27 are parallel to the axis of the main shaft 1. The inlet hole 26 communicates with the inlet annular cavity 24, and the outlet hole 27 is connected to the outlet annular cavity 25. An inlet nozzle 28 communicating with the inlet annular cavity 24 and an outlet nozzle 29 communicating with the outlet annular cavity 25 are provided on the water jacket 3. A hole is drilled on the bottom surface of the inlet annular cavity 24 communicating with the inlet nozzle 28, and a hole is drilled on the bottom surface of the outlet annular cavity 25 communicating with the outlet nozzle 29. Holes are drilled at corresponding positions at the ends of the inlet hole 26 and the outlet hole 27 on the outer wall of the main shaft 1, respectively, communicating with the inlet hole 26 and the outlet hole 27.

[0061] The inlet annular cavity 24 and the outlet annular cavity 25 are axially offset. Two drainage annular cavities 22 are provided, with both the inlet annular cavity 24 and the outlet annular cavity 25 located between the two drainage annular cavities 22. A flow passage 30 is provided inside the water jacket 3, and the two drainage annular cavities 22 and the drainage hole 23 are all connected to the flow passage 30. Sealing rings 17 are installed on both sides of the inlet annular cavity 24, both sides of the outlet annular cavity 25, and both sides of the drainage annular cavity 22. The flow passage 30 is parallel to the axis of the water jacket 3. A hole is drilled at the outer end of the water jacket 3 to form the flow passage 30, and a sealing plug 31 is connected to the outer end of the flow passage 30. A hole is drilled at the bottom of the drainage annular cavity 22 and connected to the flow passage 30.

[0062] A coolant outlet 38 is provided between the bottom of the drain ring cavity 22 and the flow channel 30. A seepage hole 39 is connected between the receiving ring groove 20 on both sides of the outlet 38 and the outlet 38 near the middle. An annular heat dissipation groove 40 is provided on the end face of the elastomer 18 facing the seepage hole 39. Several heat dissipation holes 41 are evenly distributed circumferentially on the bottom surface of the heat dissipation groove 40. The seepage hole 39 is connected to the heat dissipation groove 40. When coolant seeps out, it flows along the seepage hole 39 into the heat dissipation groove 40 and the heat dissipation holes 41 to cool the elastomer 18 of the sealing ring 17, reducing the temperature of the elastomer 18 and helping to slow down the wear of the elastomer 18, thus extending the service life of the sealing ring 17.

[0063] An air intake channel 32 is provided on the outer casing 2. A ventilation annular cavity 33 is formed between the inner wall of the mounting hole 6 and the outer wall of the main shaft 1. A ventilation hole 34 is provided inside the main shaft 1, and the ventilation hole 34 communicates with the ventilation annular cavity 33. The ventilation hole 34 is coaxially arranged with the main shaft 1. The ventilation annular cavity 33 is located on the inner wall of the support ring 11. A transition hole 35 is provided on the support ring 11, and the transition hole 35 connects the ventilation annular cavity 33 and the air intake channel 32. A connecting hole 36 is drilled at the corresponding end of the ventilation hole 34 on the outer wall of the main shaft 1. The connecting hole 36 is offset from the water inlet hole 26 and the water outlet hole 27, and the connecting hole 36 connects the ventilation annular cavity 33 and the ventilation hole 34.

[0064] An outwardly extending connecting plate 37 is provided on the outer casing 2, and the connecting plate 37 is tightly connected to the semiconductor vacuum chamber. A sealing ring is installed between the connecting plate 37 and the semiconductor vacuum chamber.

[0065] During the rotation of the main shaft 1, a magnetic fluid seal is achieved between the main shaft 1 and the outer casing 2 through a magnetic fluid sealing assembly, resulting in a good sealing effect. The main shaft 1 and the water jacket 3 are sealed by multiple axially spaced sealing rings 17. The elastic body 18 of the sealing ring 17 directly contacts the main shaft 1, exhibiting high temperature resistance, wear resistance, and a long service life. The O-rings 19 of the sealing rings 17 and the water jacket 3 form a static seal, providing a good sealing effect and minimizing leakage. A drain ring cavity 22 is provided on the inner wall of the water jacket 3. Liquid seeping from the inner wall of the water jacket 3 collects in the drain ring cavity 22 and is discharged through the drain hole 23 back into the return water channel, preventing leakage from affecting the safety of external components.

[0066] The magnetic fluid sealing device with rotating water jacket 3 used in this application for semiconductors has good sealing performance between the water jacket 3 and the spindle 1, making it less prone to water leakage. The leaked coolant can flow back into the return water channel. Even if leakage occurs under high speed and high pressure, it will not leak outside the flow channel and affect the safety of external components, thus ensuring the safe operation of the entire equipment.

[0067] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications may be made without departing from the technical solutions described in the claims.

Claims

1. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductor applications, characterized in that, It includes a spindle and a housing. The housing is fastened to a water jacket and has mounting holes. The spindle is rotatably connected to the mounting holes. A magnetohydrodynamic sealing assembly is installed between the spindle and the mounting holes. The spindle is fitted to the water jacket. Multiple sealing rings are axially spaced between the water jacket and the spindle. A drain ring cavity is provided on the inner wall of the water jacket, and a drain hole communicating with the drain ring cavity is provided on the water jacket.

2. The magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 1, characterized in that, The sealing ring includes an elastomer and an O-ring, with the O-ring disposed on the outer wall of the elastomer.

3. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 2, characterized in that, Several sealing teeth are axially spaced on the inner wall of the elastic body.

4. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 1, characterized in that, The inner wall of the water jacket is provided with an inlet ring cavity and an outlet ring cavity. The main shaft is provided with an inlet hole and an outlet hole. The inlet hole is connected to the inlet ring cavity, and the outlet hole is connected to the outlet ring cavity. The water jacket is provided with an inlet nozzle connected to the inlet ring cavity and an outlet nozzle connected to the outlet ring cavity.

5. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 4, characterized in that, Two drainage ring cavities are provided, with the inlet ring cavity and the outlet ring cavity both located between the two drainage ring cavities. A flow passage is provided inside the water jacket, and the two drainage ring cavities and the drainage hole are all connected to the flow passage.

6. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 1, characterized in that, An air intake channel is provided on the outer casing, and a ventilation annular cavity is formed between the inner wall of the mounting hole and the outer wall of the main shaft. A ventilation hole is provided inside the main shaft, and the ventilation hole is connected to the ventilation annular cavity.

7. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 1, characterized in that, The magnetofluid sealing assembly includes two sets of magnetofluid units, with a support ring between the two magnetofluid units. Each magnetofluid unit includes two magnetic poles and a magnetic block disposed between the two magnetic poles. A retaining ring is installed inside the mounting ring, and the retaining ring axially positions the magnetofluid unit. Magnetic fluid is loaded between the inner wall of the magnetic poles and the outer wall of the main shaft.

8. A magnetohydrodynamic sealing device with a rotating water jacket for semiconductors according to claim 7, characterized in that, Several sealing ring grooves corresponding to the magnetic poles are spaced apart on the outer wall of the main shaft, and the magnetic fluid is loaded in the sealing ring grooves.

9. A magnetohydrodynamic sealing device for semiconductors with a rotating water jacket according to any one of claims 1 to 8, characterized in that, A DLC coating is applied to the outer wall of the spindle.

10. A magnetohydrodynamic sealing device for semiconductors with a rotating water jacket according to any one of claims 1 to 8, characterized in that, An outwardly extending connecting plate is provided on the outer casing, and the connecting plate is tightly connected to the semiconductor vacuum chamber.

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