Sealing structure of slide valve vacuum pump

Abstract

The utility model discloses a sealing structure of a slide valve vacuum pump, which comprises a sealing body sleeved at the end part of a main shaft, a sealing moving ring is arranged in the sealing body, a gland is fixedly arranged on one side of the sealing body, a sealing static ring is arranged on the gland, one side of the sealing moving ring is propped against the sealing static ring to form a sealing surface, and the sealing surface is provided with a sealing groove. The sealing moving ring is provided with a driving piece driving one side of the sealing moving ring to abut against the sealing static ring all the time, an oil cavity used for storing oil liquid is formed in the sealing body, the two ends of the main shaft are of novel mechanical sealing structures, 200-DEG C high-temperature working conditions can be resisted, good sealing performance is achieved, therefore, the oil leakage phenomenon is reduced, the abrasion condition is low, and the service life of the main shaft is prolonged. And the mechanical seal is basically not required to be replaced in the whole service cycle of the pump, so that the use of customers is facilitated, and the service life of the pump is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of slide valve vacuum pumps, and in particular to a sealing structure for a slide valve vacuum pump. Background Technology

[0002] A slide valve vacuum pump is a variable displacement gas transfer pump that uses the movement of a slide valve mechanism to change the volume of the pump chamber, thereby extracting and discharging gas to achieve a vacuum environment. It mainly consists of a pump body, an eccentric wheel, a slide valve sleeve, and a slide valve plate. The eccentric wheel drives the slide valve mechanism to perform eccentric motion, causing the volume of the pump chamber to change periodically, thus completing the intake, compression, and exhaust processes and achieving gas delivery. It is widely used in power, manufacturing, scientific research, chemical, and other fields.

[0003] The slide valve vacuum pump has a main shaft, which serves as the drive source to rotate the deflector wheel and make eccentric motion. In actual use, sealing structures are set at both ends of the main shaft to overcome oil leakage. Currently, the seals at both ends of the main shaft are usually oil seals. When the user's working conditions are harsh, oil leakage will occur frequently, and the oil seals will need to be replaced often. The oil seals will also wear down the pump shaft, which needs to be further improved. Utility Model Content

[0004] To further improve sealing performance, this application provides a sealing structure for a slide valve vacuum pump.

[0005] This application provides a sealing structure for a slide valve vacuum pump, employing the following technical solution:

[0006] A sealing structure for a slide valve vacuum pump includes a sealing body for fitting onto the end of a main shaft. A sealing dynamic ring is disposed inside the sealing body. A pressure cap is fixedly disposed on one side of the sealing body. A sealing stationary ring is disposed on the pressure cap. One side of the sealing dynamic ring abuts against the sealing stationary ring to form a sealing surface. A driving member is disposed on the sealing dynamic ring to drive one side of it to always abut against the sealing stationary ring. An oil cavity for storing oil is formed inside the sealing body.

[0007] Optionally, the gland is provided with an installation groove for installing a sealing stationary ring, and a first sealing ring is provided between the sealing stationary ring and the gland to connect the two.

[0008] Optionally, the first sealing ring has an L-shaped cross-section and includes a horizontal portion and a vertical portion. The outer periphery of the horizontal portion is provided with a protruding ring, which is used to abut against the inner wall of the mounting groove.

[0009] Optionally, the end face of the convex ring is an arc surface and contacts the inner wall of the mounting groove, and multiple convex rings are spaced apart along the length direction of the horizontal portion.

[0010] Optionally, the sealing ring has an outer ring cavity and an inner ring cavity in the middle.

[0011] Optionally, the driving component includes a spring and is installed in the outer ring cavity, and the two ends of the outer ring cavity are provided with connecting parts for connecting to the ends of the spring.

[0012] Optionally, it also includes a pump cover, wherein a groove for mounting a bearing is provided inside the pump cover, the groove is connected to the oil chamber, a bearing is installed inside the groove, and the side of the sealing ring away from the sealing ring presses against the bearing end face.

[0013] Optionally, a bushing is provided on the side of the bearing away from the sealing ring. The bushing is used to fit onto the main shaft. A second sealing ring is provided between the bushing and the inner wall of the groove. The second sealing ring has a hollowed-out portion on the side facing the bearing and a pressing portion is formed at the bottom of the second sealing ring. The end of the pressing portion presses against the bushing.

[0014] Optionally, the inner wall of the bushing is provided with an annular groove, and a third sealing ring adapted to it is installed in the annular groove.

[0015] Optionally, the top of the sealing body is provided with a refueling channel, which is connected to the oil chamber. The end of the refueling channel away from the oil chamber is used to connect to the oil tank of the oil-gas separator of the slide valve vacuum pump.

[0016] In summary, this application includes at least one of the following beneficial technical effects:

[0017] 1. The main shaft adopts a new type of mechanical seal structure at both ends, which can withstand high temperature conditions of 200 degrees Celsius and has good sealing performance, thereby reducing oil leakage. Moreover, it has low wear and long service life. The mechanical seal basically does not need to be replaced during the entire service life of the pump, which facilitates the use of customers and improves the service life of the pump.

[0018] 2. The spring setting ensures that the sealing ring and the sealing stationary ring always maintain a good contact and sealing effect, automatically realizes the elastic compensation function, and maintains the effectiveness of the seal for a long time.

[0019] 3. The connection between the groove and the oil chamber allows for continuous lubrication of the bearing, improving the bearing's performance and service life.

[0020] 4. The design of the refueling channel allows the oil in the inner tank of the oil-gas separator to be replenished into the oil chamber for use, realizing the recycling of oil. Furthermore, the oil tank is positioned higher than the oil chamber, and the oil will automatically flow down under the action of gravity to achieve automatic replenishment. Attached Figure Description

[0021] Figure 1 This is a structural diagram of Example 1.

[0022] Figure 2 yes Figure 1 Enlarged view of point A in the middle.

[0023] Figure 3 This is a structural diagram of Example 2.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. Sealing body; 2. Main shaft; 3. Pump cover; 4. Seal ring; 5. Gland; 6. Seal ring; 7. Sealing surface; 8. Oil cavity; 9. Mounting groove; 10. First sealing ring; 11. Horizontal part; 12. Vertical part; 13. Raised ring; 14. O-ring; 15. Abutment block; 16. Outer ring cavity; 17. Inner ring cavity; 18. Spring; 19. Connecting part; 20. Bearing; 21. Groove; 22. Bushing; 23. Second sealing ring; 24. Hollowed-out part; 25. Pressing part; 26. Ring groove; 27. Third sealing ring; 28. Oil filling channel; 29. ​​Connecting hole. Detailed Implementation

[0026] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0027] Example 1

[0028] A sealing structure for a slide valve vacuum pump, such as Figure 1 and Figure 2 As shown, the system includes a sealing body 1, which is fitted onto the main shaft 2 of the slide valve vacuum pump. A pump cover 3 is provided on one side of the sealing body 1, which is used to cover one side of the pump body of the slide valve vacuum pump. The end of the main shaft 2 extends through the pump cover 3 and the sealing body 1. The sealing body 1 and the pump cover 3 are connected by bolts to achieve detachability. The inner diameter of the sealing body 1 is larger than the outer diameter of the main shaft 2, and a sealing moving ring 4 is provided inside the sealing body 1. A pressure cover 5 is provided on the side of the sealing body 1 away from the pump cover 3, and a sealing stationary ring 6 is provided on the pressure cover 5. One side of the sealing stationary ring 6 abuts against one side of the sealing moving ring 4 to form a sealing surface 7. A driving component is provided on the sealing moving ring 4 to drive one side of the sealing moving ring 4 to always abut against the sealing stationary ring 6. The driving component always maintains the abutment state between the sealing moving ring 4 and the sealing stationary ring 6, which plays a certain compensation role. An oil cavity 8 for storing oil is formed between the sealing moving ring 4, the sealing stationary ring 6, and the sealing body 1. In actual use, the sealing moving ring 4 rotates with the main shaft 2, while the sealing stationary ring 6 remains stationary.

[0029] The main shaft 2 employs a new type of mechanical seal structure at both ends, capable of withstanding high-temperature conditions up to 200 degrees Celsius. During operation, a thin oil film forms at the sealing surface 7, which balances pressure, lubricates, and cools the end faces. This sealing structure provides excellent sealing performance, reducing oil leakage, and also exhibits low wear, resulting in a longer service life. The mechanical seal essentially does not need to be replaced throughout the pump's entire service life, simplifying customer use and extending the pump's lifespan.

[0030] like Figure 1 and Figure 2 As shown, a mounting groove 9 for installing a sealing stationary ring 6 is provided inside the pressure cap 5. A first sealing ring 10 is provided between the sealing stationary ring 6 and the pressure cap 5 to connect the two. The first sealing ring 10 has an L-shaped cross-section and includes a horizontal part 11 and a vertical part 12. A protruding ring 13 is provided on the outer periphery of the horizontal part 11. The protruding ring 13 is used to abut against the inner wall of the mounting groove 9, and multiple protruding rings 13 are distributed at intervals along the length direction of the horizontal part 11. The end face of the protruding ring 13 is an arc surface and is in line contact with the inner wall of the mounting groove 9. The contact area of ​​the line contact is small. The end of the convex ring 13 has better deformation capability. Under force, the pressure at the end of the convex ring 13 is greater and more concentrated, which makes the end of the convex ring 13 have better sealing performance. Multiple spaced convex rings 13 form a multi-stage seal, which further improves the sealing effect and achieves better anti-leakage performance, preventing oil from flowing out from the gap between the gland 5 and the main shaft 2. In addition, an O-ring 14 is provided on the outer ring of the gland 5. The O-ring 14 achieves the seal between the gland 5 and the sealing body 1, preventing oil from leaking between the gland 5 and the sealing body 1.

[0031] like Figure 1 and Figure 2 The sealing ring 4 has an abutment block 15 on the side near the sealing stationary ring 6. The abutment block 15 abuts against the sealing stationary ring 6. The abutment block 15 is made of graphite, which has better wear resistance and effectively extends service life. The sealing ring 4, like the first sealing ring 10, is made of soft material with deformation capability. An outer ring cavity 16 and an inner ring cavity 17 are provided in the middle of the sealing ring 4. This makes the thickness of the middle part of the sealing ring 4 less than that of the two ends, so that the middle part of the sealing ring 4 has better deformation capability. The design of the inner ring cavity 17 reduces the contact area between the sealing ring 4 and the main shaft 2, which facilitates the axial deformation of the sealing ring 4. The design of the outer ring cavity 16 can expand the space of the oil cavity 8, so that the oil cavity 8 can store more oil.

[0032] like Figure 1 and Figure 2As shown, the driving component is a spring 18, which is sleeved on the sealing moving block. The spring 18 is installed in the outer ring cavity 16, and the two ends of the sealing moving ring 4 are provided with connecting parts 19 for connecting with the ends of the spring 18. The connecting parts 19 are made of hard material, such as stainless steel. When the spring 18 is in a compressed state, the two ends of the sealing moving ring 4 are driven to move in opposite directions by the elastic force of the spring 18, so that the abutting block 15 at one end of the sealing moving ring 4 is always in contact with the sealing stationary ring 6.

[0033] like Figure 1 and Figure 2 As shown, a groove 21 for mounting the bearing 20 is provided inside the pump cover 3. The groove 21 is connected to the oil chamber 8. The groove 21 is a stepped groove, so that the oil in the oil chamber 8 can flow into the bearing 20 to lubricate it and extend the service life of the bearing 20. The side of the sealing ring 4 away from the sealing ring 6 abuts against the bearing 20, and the bearing 20 plays an axial blocking and limiting role for the sealing ring 4.

[0034] like Figure 1 and Figure 2 As shown, a bushing 22 is provided on the side of the bearing 20 away from the sealing ring 4. The bushing 22 is used to fit onto the main shaft 2. A second sealing ring 23 is provided between the bushing 22 and the inner wall of the groove 21. The second sealing ring 23 has a hollowed-out portion 24 on the side facing the bearing 20 and a pressing portion 25 is formed at the bottom of the second sealing ring 23. The end of the pressing portion 25 presses against the bushing 22, so that the oil in the oil chamber 8 can enter the hollowed-out portion 24. The oil pressure can promote the downward deformation of the pressing portion 25 to better press against the bushing 22, effectively improving the sealing performance at the connection between the pressing portion 25 and the bushing 22. The second sealing ring 23 as a whole achieves the sealing between the pump cover 3 and the bushing 22. In addition, an annular groove 26 is provided on the inner wall of the bushing 22. A third sealing ring 27 adapted to it is installed in the annular groove 26. The sealing performance between the bushing 22 and the main shaft 2 is improved by means of the third sealing ring 27.

[0035] like Figure 1 and Figure 2 As shown, a refueling channel 28 for replenishing oil is provided on the top of the sealing body 1. The bottom end of the refueling channel 28 is connected to the oil chamber 8, and the top end of the refueling channel 28 is connected to the oil tank of the oil-gas separator of the slide valve vacuum pump. The design of the refueling channel 28 can replenish the oil in the inner oil tank of the oil-gas separator to the oil chamber 8 for use, realizing the circulation of oil. In addition, the oil tank is higher than the oil chamber 8, and the oil will automatically flow down under the action of gravity to achieve automatic replenishment.

[0036] Example 2

[0037] A sealing structure for a slide valve vacuum pump, such as Figure 3As shown, the main difference between this embodiment and Embodiment 1 lies in the structure of the sealing ring 4. In this embodiment, the sealing ring 4 has a connecting hole 29 in the middle that connects the outer ring cavity 16 and the inner ring cavity 17. The connecting hole 29 enables the oil in the outer ring cavity 16 to communicate with the inner ring cavity 17, maintaining the oil pressure balance between the inner ring cavity 17 and the outer ring cavity 16. This allows the sealing ring 4 to deform more effectively to achieve the function of elastic compensation.

[0038] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A sealing structure for a slide valve vacuum pump, characterized in that: It includes a sealing body (1) for fitting onto the end of the main shaft (2), a sealing moving ring (4) is provided inside the sealing body (1), a pressure cap (5) is fixedly provided on one side of the sealing body (1), a sealing stationary ring (6) is provided on the pressure cap (5), one side of the sealing moving ring (4) abuts against the sealing stationary ring (6) to form a sealing surface (7), a driving member is provided on the sealing moving ring (4) to drive one side of it to always abut against the sealing stationary ring (6), and an oil cavity (8) for storing oil is formed inside the sealing body (1).

2. The sealing structure of a slide valve vacuum pump according to claim 1, characterized in that: The pressure cap (5) is provided with an installation groove (9) for installing the sealing stationary ring (6), and a first sealing ring (10) is provided between the sealing stationary ring (6) and the pressure cap (5) to connect the two.

3. The sealing structure of a slide valve vacuum pump according to claim 2, characterized in that: The first sealing ring (10) has an L-shaped cross section and includes a horizontal part (11) and a vertical part (12). The outer periphery of the horizontal part (11) is provided with a protruding ring (13), which is used to abut against the inner wall of the mounting groove (9).

4. The sealing structure of a slide valve vacuum pump according to claim 3, characterized in that: The end face of the convex ring (13) is an arc surface and is in contact with the inner wall of the mounting groove (9). Multiple convex rings (13) are distributed at intervals along the length direction of the horizontal part (11).

5. The sealing structure of a slide valve vacuum pump according to claim 1, characterized in that: The sealing ring (4) has an outer ring cavity (16) and an inner ring cavity (17) in the middle.

6. The sealing structure of a slide valve vacuum pump according to claim 5, characterized in that: The driving component includes a spring (18) and is installed in an outer ring cavity (16), with connecting portions (19) at both ends of the outer ring cavity (16) for connecting to the ends of the spring (18).

7. The sealing structure of a slide valve vacuum pump according to claim 1, characterized in that: It also includes a pump cover (3), in which a groove (21) for mounting a bearing (20) is provided. The groove (21) is connected to the oil chamber (8). The bearing (20) is installed in the groove (21). The side of the sealing ring (4) away from the sealing ring (6) presses against the end face of the bearing (20).

8. The sealing structure of a slide valve vacuum pump according to claim 7, characterized in that: A bushing (22) is provided on the side of the bearing (20) away from the sealing ring (4). The bushing (22) is used to fit onto the main shaft (2). A second sealing ring (23) is provided between the bushing (22) and the inner wall of the groove (21). The second sealing ring (23) has a hollowed-out part (24) on the side facing the bearing (20) and a pressing part (25) is formed at the bottom of the second sealing ring (23). The end of the pressing part (25) presses against the bushing (22).

9. The sealing structure of a slide valve vacuum pump according to claim 8, characterized in that: The inner wall of the bushing (22) is provided with an annular groove (26), and a third sealing ring (27) adapted to it is installed in the annular groove (26).

10. The sealing structure of a slide valve vacuum pump according to claim 1, characterized in that: The top of the sealing body (1) is provided with a refueling channel (28), which is connected to the oil chamber (8). The end of the refueling channel (28) away from the oil chamber (8) is used to connect to the oil tank of the oil-gas separator of the slide valve vacuum pump.

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