Vacuum pump lubricating structure

Abstract

The invention relates to the technical field of vacuum pump lubrication, in particular to a vacuum pump lubrication structure. Comprising a center hole, the center hole is formed along the axis of the main shaft, an opening of the center hole faces downwards, an inner cone dip angle is arranged at the opening, an oil storage pool is arranged at the bottom end of the main shaft, and the bottom end of the main shaft is immersed in the oil storage pool; the liquid spraying hole is formed in the main shaft, one end of the liquid spraying hole communicates with the center hole, and the other end of the liquid spraying hole communicates with the outer side wall of the main shaft and is located above the bearing. During use, the main shaft rotates at a high speed, lubricating oil in the oil storage pool rises along the center hole from the inclination angle of the inner cone of the opening of the center hole under the action of centrifugal force and then is sprayed out through the liquid spraying hole, and when meeting the liquid distribution plate, the lubricating oil can be blocked on the liquid distribution plate and then vertically and downwards flows into the bearing, so that the effect of lubricating the bearing is achieved; and when the liquid does not meet the liquid separation plate, the liquid can be jetted to the shell and flows back to the oil storage pool through the liquid collection tank and the liquid discharge hole.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum pump lubrication, and in particular to a vacuum pump lubrication structure. Background Art

[0002] Vacuum pumps such as molecular pumps are generally lubricated with lubricating fluid, and the lubricating fluid also conducts heat and cools the spindle and other parts. At present, a widely used lubricating fluid structure design is to spray lubricating fluid along the center hole of the spindle and from the spray hole to lubricate the bearings and conduct heat and cool the spindle, and finally flow down along the bearings. However, in general, the flow rate of lubricating fluid required for bearing lubrication is much lower than the flow rate of lubricating fluid required for heat conduction and cooling of parts such as the spindle. The existing technology has the problem of unsatisfactory cooling effect and the inability to divert and adjust the lubricating fluid. Summary of the invention

[0003] In view of this, the present invention provides a vacuum pump lubrication structure to solve the problems in the prior art that the lubricating fluid has an unsatisfactory cooling effect and the lubricating fluid cannot be diverted and adjusted.

[0004] The present invention provides a vacuum pump lubrication structure, which is arranged on the main shaft of the vacuum pump, and a bearing is arranged between the housing and the main shaft of the vacuum pump, comprising:

[0005] A center hole is opened along the axis of the main shaft, the opening of the center hole faces downward and an inner cone inclination is arranged at the opening, an oil reservoir is arranged at the bottom end of the main shaft and the bottom end of the main shaft is immersed in the oil reservoir;

[0006] A liquid spray hole is arranged on the main shaft, one end of which is connected to the central hole, and the other end of which is connected to the outer wall of the main shaft and is located above the bearing;

[0007] The bearing seat is arranged between the bearing and the housing. A plurality of liquid separators are arranged on the top of the bearing seat. A liquid collecting trough is arranged on the bearing seat. The liquid collecting trough is located on the side of the liquid separator plate away from the main shaft. The bearing seat is also provided with a drainage hole connecting the liquid collecting trough and the bottom end of the bearing seat.

[0008] When the present invention is used, the spindle rotates at high speed, and under the action of centrifugal force, the lubricating oil in the oil reservoir rises along the center hole from the inner cone inclination of the center hole opening, and then sprays out through the spray hole. When it encounters the separator plate, it will be blocked on the separator plate, and then flow vertically downward into the bearing to lubricate the bearing; when it does not encounter the separator plate, it will spray onto the housing, and return to the oil reservoir through the collecting tank and the drain hole. The lubricating liquid is completely returned to the oil reservoir, waiting to be transported to the spindle again. The present application can enhance the cooling effect through the drain hole, and can also divert and adjust the lubricating liquid.

[0009] In an optional embodiment, there are at least two liquid spray holes, which are evenly spaced and distributed along the axis of the main shaft, so as to ensure the dynamic balancing accuracy of the main shaft and avoid imbalance of the main shaft.

[0010] In an optional embodiment, the liquid spray hole is opened horizontally, so that the force on the main shaft is relatively balanced and the main shaft is prevented from being subjected to force in the vertical direction.

[0011] In an optional embodiment, a cover plate is provided above the bearing, which is suitable for sealing the upper part of the bearing, the main shaft passes through the cover plate, and the liquid spray hole is connected to the opening on the outer wall of the main shaft and is located between the bearing and the cover plate. The cover plate can prevent the lubricating liquid from spraying out from the upper part of the bearing.

[0012] In an optional embodiment, the liquid separation plates are evenly spaced and distributed along the axis of the main shaft, so as to ensure the dynamic balancing accuracy of the vacuum pump and the main shaft and ensure uniform lubrication of the bearings.

[0013] In an optional embodiment, the liquid separation plate is an arc-shaped structure surrounding the axis of the main shaft and is located on the same annular surface, so as to ensure the dynamic balancing accuracy of the vacuum pump and the main shaft.

[0014] In an optional embodiment, the drainage hole is vertically arranged, which can save the size of the bearing seat parts, increase the heat conduction area during drainage, and reduce the operating temperature of the bearing seat.

[0015] In an optional embodiment, the drainage hole corresponds to the position of the liquid separation plate, and the drainage hole and the corresponding liquid separation plate are located in the same radial direction.

[0016] In an optional embodiment, the top of the liquid separation plate is not lower than the top of the liquid spray hole, so as to ensure that the liquid separation plate blocks the lubricating liquid and prevents the lubricating liquid from spraying out from above the liquid separation plate.

[0017] In an optional implementation, it also includes:

[0018] The liquid collecting wall is an annular structure, which is arranged at the top of the bearing seat and located on the side of the liquid collecting tank away from the liquid separation plate, and the top of the liquid collecting wall abuts against the cover plate. The liquid collecting wall can block the lubricating liquid that the liquid separation plate cannot block, so that the lubricating liquid enters the liquid collecting tank. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0021] Figure 2 A top view of an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the molecular flow region structure of a molecular pump according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the molecular pump pumping of an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the structure of a molecular pump according to an embodiment of the present invention.

[0025] Description of reference numerals:

[0026] 1. Spindle; 2. Housing; 3. Bearing; 4. Center hole; 5. Spray hole; 6. Bearing seat; 7. Cover plate; 8. Separator plate; 9. Liquid collecting tank; 10. Drain hole; 11. Liquid collecting wall. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0028] Combine the following Figures 1 to 5 , describing an embodiment of the present invention.

[0029] According to an embodiment of the present invention, a vacuum pump lubrication structure is provided, which is arranged on the main shaft 1 of the vacuum pump, and a bearing 3 is arranged between the housing 2 of the vacuum pump and the main shaft 1. It should be noted that the vacuum pump for cooling and lubricating by lubricating oil needs to be arranged vertically, mainly to ensure the normal circulation and distribution of the lubricating oil, including:

[0030] A center hole 4 is opened along the axis of the spindle 1, the opening of the center hole 4 faces downward and an inner cone inclination is provided at the opening, an oil reservoir is provided at the bottom end of the spindle 1 and the bottom end of the spindle 1 is immersed in the oil reservoir;

[0031] A liquid spray hole 5 is provided on the main shaft 1, one end of which is connected to the central hole 4, and the other end of which is connected to the outer wall of the main shaft 1 and is located above the bearing 3;

[0032] The bearing seat 6 is arranged between the bearing 3 and the housing 2. A plurality of liquid separators 8 are arranged at the top of the bearing seat 6. A liquid collecting groove 9 is arranged on the bearing seat 6. The liquid collecting groove 9 is located on the side of the liquid separator 8 away from the main shaft 1. The bearing seat 6 is also provided with a drainage hole 10 connecting the liquid collecting groove 9 and the bottom end of the bearing seat 6. The top end of the liquid separator 8 can be higher than the top end of the bearing 3 and not lower than the bottom end of the liquid injection hole 5. The bottom end of the liquid collecting groove 9 can be lower than the bottom end of the liquid separator 8. The liquid collecting groove 9 can be an annular groove.

[0033] When the present invention is used, the spindle 1 rotates at a high speed, and the speed can reach tens of thousands of RPM. Under the action of centrifugal force, the lubricating oil in the oil reservoir rises along the center hole 4 from the inner cone inclination of the center hole opening, and then sprays out through the spray hole 5. When it encounters the liquid separation plate 8, it will be blocked on the liquid separation plate 8, and then flow vertically downward into the bearing 3 to lubricate the bearing 3; when it does not encounter the liquid separation plate 8, it will be sprayed onto the housing 2, and return to the oil reservoir through the liquid collection tank 9 and the drainage hole 10. The lubricating liquid is completely returned to the oil reservoir, waiting to be transported to the spindle 1 again. The present application can enhance the cooling effect through the drainage hole 10, and can divert and adjust the lubricating liquid.

[0034] In an optional embodiment, there are at least two liquid spray holes 5, which are evenly spaced and distributed along the axis of the main shaft 1. This ensures the dynamic balancing accuracy of the main shaft 1 and prevents the main shaft 1 from being unbalanced.

[0035] In an optional embodiment, the liquid spray hole 5 is opened horizontally, so that the force on the main shaft 1 is relatively balanced and the main shaft 1 is prevented from being subjected to force in the vertical direction.

[0036] In an optional embodiment, a cover plate 7 is provided above the bearing 3, which is suitable for sealing the upper part of the bearing 3, the main shaft 1 passes through the cover plate 7, and the liquid spray hole 5 is connected to the opening on the outer wall of the main shaft 1 and is located between the bearing 3 and the cover plate 7. The cover plate 7 can prevent the lubricating liquid from spraying out from the upper part of the bearing 3. The cover plate 7 can be fixed on the inner side of the housing 2, and can rotate relative to the main shaft 1.

[0037] In an optional embodiment, the liquid separation plates 8 are evenly spaced along the axis of the main shaft 1. The liquid separation plates 8 can be single or multiple and spaced on the circumference. The dynamic balancing accuracy of the vacuum pump and the main shaft 1 can be ensured, and the lubrication of the bearing 3 can be uniform.

[0038] In an optional embodiment, the liquid separator 8 is an arc-shaped structure surrounding the axis of the main shaft 1 and is located on the same annular surface, which can enhance the barrier effect of the liquid separator 8 on the lubricating liquid.

[0039] The present application can realize the separation of the flow rate for lubricating the bearing 3 and the flow rate for cooling. If the flow rate for lubrication needs to be increased, it is only necessary to increase the width of the liquid separation plate 8, that is, to increase the width of the liquid separation plate 8. Figure 2 The arc center angle of the liquid separation plate 8 in the top view can achieve the adjustment of any flow rate, solving the problem that the lubrication flow rate cannot be adjusted.

[0040] The function of the flow distribution of the liquid distribution plate 8 is to distribute the flow according to a certain proportion of the total injection flow, that is, the proportion of the flow distributed to the bearing 3 to the total injection amount is theoretically equal to the proportion of the sum of the central angles of the liquid distribution plate 8 on a circumference, refer to Figure 2 In the top view, there will be engineering deviation and splash loss of lubricating fluid in actual application. When the flow rate of the liquid spraying hole 5 in the main shaft 1 increases, the flow rate of the diverted flow will increase in the same proportion.

[0041] In an optional embodiment, the drainage hole 10 is vertically arranged, which can save the size of the parts of the bearing seat 6, increase the heat conduction area during drainage, and reduce the working temperature of the bearing seat 6.

[0042] In an optional embodiment, the drainage hole 10 corresponds to the position of the liquid separation plate 8, and the drainage hole 10 and the corresponding liquid separation plate 8 are located in the same radial direction. The liquid separation plate 8 is located on the same annular surface, and the drainage hole 10 is located on the side of the liquid separation plate 8 away from the center of the annular surface. The shape of the drainage hole 10 can be waist-shaped or circular, and this embodiment is not limited thereto.

[0043] In an optional embodiment, the top of the liquid separation plate 8 is not lower than the top of the liquid spray hole 5. This ensures that the liquid separation plate 8 blocks the lubricating liquid and prevents the lubricating liquid from spraying out from above the liquid separation plate 8.

[0044] In an optional implementation, it also includes:

[0045] The liquid collecting wall 11 is an annular structure, which is arranged at the top of the bearing seat 6, and is located on the side of the liquid collecting tank 9 away from the liquid separation plate 8, and the top of the liquid collecting wall 11 abuts against the cover plate 7. The liquid collecting wall 11 can block the lubricating liquid that the liquid separation plate 8 cannot block, so that the lubricating liquid enters the liquid collecting tank 9.

[0046] The liquid separation plate 8 and the liquid collecting wall 11 may be located at the inner end and the outer end of the bearing seat 6 respectively.

[0047] It should be noted that the turbomolecular pump uses high-speed rotating moving blades and stationary fixed blades to cooperate with each other. In the molecular flow area, the gas molecules collide with the high-speed rotating blade surface, and the momentum is transferred to the gas molecules, so that some gas molecules obtain tangential velocity in the direction of motion of the rigid body surface, produce directional compression, flow and are discharged out of the pump, thereby achieving the purpose of pumping. Figure 3 and Figure 4 shown.

[0048] The molecular pump consists of a pumping structure, a motor, a bearing 3, a main shaft 1, a pump body and other structural parts, such as Figure 5 The motor is used to drive the main shaft 1 and the turbine rotor.

[0049] Molecular pumps can achieve high vacuum and ultra-high vacuum, and are widely used in the semiconductor industry, lighting industry, solar energy industry, optical components, and thin film industry. With the increasing process load requirements of the application industry, the reliability of the molecular pump rotor operation and real-time status monitoring are becoming more and more important, especially the non-contact real-time monitoring of the actual temperature of the turbine rotor.

[0050] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A vacuum pump lubrication structure, arranged on a main shaft (1) of a vacuum pump, wherein a bearing (3) is arranged between a housing (2) of the vacuum pump and the main shaft (1), characterized in that: include: A center hole (4) is opened along the axis of the main shaft (1), the opening of the center hole (4) faces downward and an inner cone inclination is arranged at the opening, an oil reservoir is arranged at the bottom end of the main shaft (1) and the bottom end of the main shaft (1) is immersed in the oil reservoir; A liquid spray hole (5) is arranged on the main shaft (1), one end of which is connected to the central hole (4), and the other end of which is connected to the outer wall of the main shaft (1) and is located above the bearing (3); A bearing seat (6) is arranged between the bearing (3) and the housing (2); a plurality of liquid separation plates (8) are arranged at the top of the bearing seat (6); a liquid collecting trough (9) is arranged on the bearing seat (6); the liquid collecting trough (9) is located on a side of the liquid separation plate (8) away from the main shaft (1); and the bearing seat (6) is also provided with a drainage hole (10) connecting the liquid collecting trough (9) and the bottom end of the bearing seat (6).

2. The vacuum pump lubrication structure according to claim 1, characterized in that: There are at least two liquid spray holes (5), which are evenly spaced and distributed along the axis of the main shaft (1).

3. The vacuum pump lubrication structure according to claim 2, characterized in that: The liquid spray hole (5) is opened horizontally.

4. The vacuum pump lubrication structure according to claim 1, characterized in that: A cover plate (7) is provided above the bearing (3) and is suitable for sealing the upper part of the bearing (3); the main shaft (1) passes through the cover plate (7); the liquid spray hole (5) is connected to the opening on the outer wall of the main shaft (1) and is located between the bearing (3) and the cover plate (7).

5. The vacuum pump lubrication structure according to claim 4, characterized in that: The liquid separation plates (8) are evenly spaced and distributed along the axis of the main shaft (1).

6. The vacuum pump lubrication structure according to claim 1, characterized in that: The liquid separation plate (8) is an arc-shaped structure surrounding the axis of the main shaft (1) and is located on the same annular surface.

7. The vacuum pump lubrication structure according to claim 6, characterized in that: The drainage hole (10) is arranged vertically.

8. The vacuum pump lubrication structure according to claim 7, characterized in that: The drainage hole (10) corresponds to the position of the liquid separation plate (8), and the drainage hole (10) and the corresponding liquid separation plate (8) are located in the same radial direction.

9. The vacuum pump lubrication structure according to claim 1, characterized in that: The top of the liquid separation plate (8) is not lower than the top of the liquid spray hole (5).

10. The vacuum pump lubrication structure according to claim 4, characterized in that: Also includes: The liquid collecting wall (11) is an annular structure and is arranged at the top end of the bearing seat (6) and is located on a side of the liquid collecting tank (9) away from the liquid separation plate (8). The top end of the liquid collecting wall (11) abuts against the cover plate (7).

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