Vacuum pump outer end axial lubrication-free sealing surface mechanical seal sealing element structure

Abstract

The utility model relates to a mechanical seal sealing element structure of an axial lubrication-free sealing surface at the outer end of a vacuum pump, aiming at solving the technical problems that a sealing friction surface at a movable ring of the existing like product is less and adopts a bidirectional special curve spiral groove structure, and the oil quantity demand of lubricating oil is larger. According to the key points, one side of a movable ring of the structure is attached to a sealing friction surface of a static ring, and a bidirectional special curve spiral groove is machined in the inner and outer diameter circumferential direction; one ends of the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves, which are symmetrically arranged in pairs at equal intervals, of the two-way special curve spiral grooves are folded in the direction opposite to the rotating direction of the vacuum pump transmission shaft; a sealing weir is formed between another outer diameter direction special curve spiral groove and another inner diameter direction special curve spiral groove between the outer diameter direction special curve spiral groove and the inner diameter direction special curve spiral groove which extend into the inner side and the rear part of the folding part in a following manner; when the special curve spiral groove of the moving ring and the vacuum pump transmission shaft synchronously rotate at a high speed, inward suction force is generated, and lubricating oil is sucked into the sealing friction face of the moving ring to form a liquid film.

Description

TECHNICAL FIELD

[0001] The utility model relates to a vacuum pump, and is a kind of vacuum pump outer end axial non-lubrication sealing surface machine seal structure. BACKGROUND

[0002] Vacuum pump is a kind of special equipment for conveying gas, and is widely used in gas pumping and conveying in various industries;But the current vacuum pump outer end axial seal is skeleton oil seal, and it is a kind of ordinary sealing friction surface, with short service life and easy to leak air and oil.The existing vacuum pump, such as the application number 202422016712.4 disclosed in Chinese patent documents, authorized on May 16, 2025, and the utility model name "a cavitation visualization liquid ring vacuum pump device";Again, such as the application number 202220967409.0 disclosed in Chinese patent documents, authorized on December 6, 2022, and the utility model name "a high sealing screw vacuum pump";And such as the application number 201720376558.9 disclosed in Chinese patent documents, authorized on January 5, 2018, and the utility model name "a heat dissipation roots vacuum pump";The sealing friction surface of the above-mentioned vacuum pump and similar products is less likely to use bidirectional special curve spiral groove structure, and it is difficult to realize oil supply and cooling through a small amount of lubricating oil and small vacuum pump oil tank, and the cooling effect is difficult to guarantee, and the overall structure is inconvenient to disassemble. SUMMARY

[0003] In order to overcome the above-mentioned shortcomings, the purpose of the utility model is to provide a kind of vacuum pump outer end axial non-lubrication sealing surface machine seal structure in the field, so as to solve the technical problems that the sealing friction surface of the dynamic ring of the existing similar products is less likely to use bidirectional special curve spiral groove structure, and it is difficult to realize oil supply and cooling through a small amount of lubricating oil and small vacuum pump oil tank, and the cooling effect is difficult to guarantee, and the overall structure is inconvenient to disassemble.The purpose is realized through the following technical scheme.

[0004] The application relates to a structure of a mechanical seal of an outer end axial non-lubricating sealing surface of a vacuum pump, which comprises a dynamic ring and a static ring, the dynamic ring is connected with a vacuum pump driving shaft through a shaft sleeve, a locking ring at the outer diameter of one end of the shaft sleeve is locked to the vacuum pump driving shaft through locking screws penetrating from one side, the gap between the vacuum pump driving shaft and the shaft sleeve is sealed by a first 0-shaped rubber ring, the dynamic ring is tightly attached to the static ring for high-speed relative rotation sealing by a set of small springs arranged on the mechanical seal shaft sleeve, the spring force direction of the small springs is consistent with the vacuum suction force in the vacuum pump oil tank, and the sealing friction surface of the dynamic ring is prevented from leaking due to the vacuum suction opening; the static ring is installed in a mechanical seal gland, the mechanical seal gland is fixed on the vacuum pump cavity through connecting bolts and is sealed by a third 0-shaped rubber ring; the sealing friction surface on one side of the dynamic ring is attached to one side of the static ring to form a mechanical seal friction surface. The structural design points are that bidirectional special curve spiral grooves are arranged on the sealing friction surface of the dynamic ring in the circumferential direction of the inner and outer diameters, the bidirectional special curve spiral grooves comprise outer diameter direction special curve spiral grooves and inner diameter direction special curve spiral grooves, the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves symmetrically arranged at equal intervals are arranged at one end of the dynamic ring in the reverse direction of the rotation direction of the vacuum pump driving shaft, the inner side of the gathered part is formed between another outer diameter direction special curve spiral groove and another inner diameter direction special curve spiral groove which are extended into from the rear part, and the sealing weir is formed between the outer diameter direction special curve spiral groove and the inner diameter direction special curve spiral groove; when the special curve spiral grooves of the dynamic ring rotate at a high speed synchronously with the vacuum pump driving shaft, inward suction force is generated and lubricating oil is sucked into the sealing friction surface of the dynamic ring to form a liquid film. The sealing friction surface of the dynamic ring adopts the bidirectional special curve spiral groove structure, the oil amount in the vacuum pump oil tank is small, only a small amount of oil is needed to be thrown on the mechanical seal to play a cooling role, and the set structure is extremely convenient to install and disassemble. That is, the bidirectional special curve spiral groove structure of the dynamic ring is a special form of dry gas sealing, and ordinary dry gas sealing is difficult to be used in similar vacuum pumps.

[0005] The outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves of the dynamic ring are respectively arranged in an arc shape between the two ends, the gap at the gathered end of the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves is arranged in an arc shape in parallel, and the sealing weir at the other end is triangularly opened and integrally formed on the inner wall of the dynamic ring.

[0006] The outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves of the dynamic ring are respectively arranged in twelve groups of symmetry at equal intervals with the vacuum pump driving shaft as a circle, and one group of the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves are arranged at an angle of 45 degrees between the first and the last with the vacuum pump driving shaft as a circle.

[0007] The rotating ring, stationary ring, mechanical seal bushing on one side of the rotating ring, and mechanical seal gland on the side of the stationary ring are integrated with the bushing to form a mechanical seal. The mechanical seal is pushed into the vacuum pump drive shaft, the bolts connecting the mechanical seal gland to the vacuum pump cavity are tightened, and the locking screw inside the locking ring is locked onto the vacuum pump drive shaft. The locking ring is located on the atmospheric side outside the vacuum pump oil tank. In other words, during installation, simply pushing the mechanical seal into the vacuum pump drive shaft, tightening the bolts connecting the mechanical seal gland to the vacuum pump cavity, and locking the locking screw inside the locking ring onto the vacuum pump drive shaft completes the installation of the mechanical seal, facilitating both installation and removal.

[0008] An oil slinger is provided on the outer diameter of the vacuum pump drive shaft at the other end of the bushing. This allows the vacuum pump drive shaft to sling lubricating oil onto the mechanical seal during high-speed rotation, thus providing a cooling effect.

[0009] A second O-ring is provided at the engagement point between the outer sleeve of the small spring and the mechanical seal sleeve.

[0010] This utility model has a reasonable structural design, is easy to disassemble and use, occupies little oil tank space, requires less lubricating oil, and has a guaranteed cooling effect. In particular, the sealing friction surface of the rotating ring adopts a novel bidirectional special curved spiral groove structure design. It is suitable for use as a mechanical seal structure for the axial unlubricated sealing surface of the outer end of a vacuum pump, as well as for structural improvements of similar products. Attached Figure Description

[0011] Figure 1 This is a partial cross-sectional structural schematic diagram of the present invention. The vacuum pump oil tank is not specifically drawn in the figure.

[0012] Figure 2 yes Figure 1 The diagram shows the internal cross-sectional structure of the moving ring. The inner wall of the moving ring is not shown in detail. The rotation arrow indicates the rotation direction of the vacuum pump drive shaft.

[0013] Attached Figures and Their Names: 1. Vacuum Pump Drive Shaft; 2. Oil Thrower Pan; 3. First O-ring; 4. Second O-ring; 5. Small Spring; 6. Moving Ring; 601. Special Curved Spiral Groove in Outer Diameter Direction; 602. Special Curved Spiral Groove in Inner Diameter Direction; 603. Sealing Weir; 7. Stationary Ring; 8. Vacuum Pump Chamber; 9. Third O-ring; 10. Locking Screw; 11. Locking Ring; 12. Snap Ring; 13. Shaft Sleeve; 14. Mechanical Seal Gland; 15. Mechanical Seal Shaft Sleeve; 16. Vacuum Pump Oil Tank; 17. Connecting Bolt. Implementation

[0014] The structure and use of this utility model will now be further described with reference to the accompanying drawings. Figures 1-2As shown, the structure comprises a dynamic ring 6 and a static ring 7, the dynamic ring is connected with the vacuum pump drive shaft 1 through a shaft sleeve 13, the outer diameter of the locking ring 11 at one end of the shaft sleeve is locked to the vacuum pump drive shaft by the locking screw 10 penetrating from one side, the gap between the vacuum pump drive shaft and the shaft sleeve is sealed by the first 0-shaped rubber ring 3, the dynamic ring is tightly attached to the static ring for relative high-speed rotation sealing by the thrust provided by a group of small springs 5 arranged on the mechanical seal shaft sleeve 15, the spring force direction of the small springs is consistent with the vacuum suction force in the vacuum pump oil tank 16, the static ring is installed in the mechanical seal gland 14, the mechanical seal gland is fixed on the vacuum pump cavity 8 by the connecting bolt 17 and is sealed by the third 0-shaped rubber ring 9, the sealing friction surface on one side of the dynamic ring is attached to one side of the static ring to form a mechanical sealing friction surface. The sealing friction surface of the dynamic ring is processed with bidirectional special curve spiral grooves in the circumferential direction of the inner and outer diameters, the bidirectional special curve spiral grooves include outer diameter direction special curve spiral grooves 601 and inner diameter direction special curve spiral grooves 602, the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves arranged symmetrically and equidistantly in pairs at the dynamic ring are gathered in one end against the rotation direction of the vacuum pump drive shaft, the inner side of the gathering part and the other outer diameter direction special curve spiral grooves and inner diameter direction special curve spiral grooves trailingly extended form a sealing weir 603 between the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves, when the special curve spiral grooves of the dynamic ring rotate synchronously and at high speed with the vacuum pump drive shaft, inward suction force is generated and lubricating oil is sucked into the sealing friction surface of the dynamic ring to form a liquid film.

[0015] The outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves of the dynamic ring are respectively arranged in arc shape between the two ends, the gap between the gathering ends of the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves is in arc shape and parallel, the sealing weir at the other end is triangularly opened and is integrally formed on the inner wall of the dynamic ring. The outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves of the dynamic ring are arranged symmetrically and equidistantly in twelve groups with the vacuum pump drive shaft as a circle, one group of the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves are arranged at an angle of 45 degrees between the first and the last with the vacuum pump drive shaft as a circle.

[0016] The dynamic ring and the static ring, and the mechanical seal shaft sleeve on one side of the dynamic ring and the mechanical seal gland on one side of the static ring are integrally connected with the shaft sleeve to form a mechanical seal, the mechanical seal is pushed into the vacuum pump drive shaft, the mechanical seal gland connecting bolt is tightened with the vacuum pump cavity, and the locking screw 10 in the locking ring is locked on the vacuum pump drive shaft, and the locking ring is arranged on the atmospheric side of the vacuum pump oil tank. The outer diameter of the vacuum pump drive shaft at the other end of the shaft sleeve is provided with an oil throwing disc 2, and the shaft sleeve and the mechanical seal shaft sleeve are sleeved at the outer side of the small spring.

[0017] The installation of the structure is as follows: the mechanical seal is sleeved on the vacuum pump driving shaft 1, the mechanical seal gland 14 is connected with the vacuum pump cavity 8, the connecting bolt 17 is tightened, the locking screw 10 in the locking ring 11 is locked, and the shaft sleeve 13 is fixed on the vacuum pump driving shaft.

[0018] In summary, the structure relates to the application of the mechanical seal without lubricated sealing surface in the vacuum pump outside axial sealing structure, and is a mechanical seal which seals the vacuum pump driving shaft between the vacuum pump oil tank and the outside atmosphere. The mechanical seal of the structure is installed on the vacuum pump driving shaft in the vacuum pump oil tank and connected with the vacuum pump cavity to realize the rotary sealing, so as to prevent the atmosphere from being sucked into the oil tank by the vacuum or the lubricating oil from leaking to the atmosphere to pollute the environment.

Claims

1. A vacuum pump outer end axial non-lubrication sealing surface mechanical seal structure, the structure comprising a dynamic ring (6) and a static ring (7), the dynamic ring is connected with a vacuum pump drive shaft (1) through a shaft sleeve (13), a locking ring (11) at the outer diameter of one end of the shaft sleeve is locked to the vacuum pump drive shaft through a locking screw (10) penetrating from one side, the gap between the vacuum pump drive shaft and the shaft sleeve is sealed by a first 0-shaped rubber ring (3), the dynamic ring is provided with a set of small springs (5) arranged on a mechanical seal shaft sleeve (15) to provide thrust force to make the dynamic ring tightly adhere to the static ring for high-speed relative rotation sealing, the spring force direction of the small springs is consistent with the vacuum suction force in a vacuum pump oil tank (16), the static ring is installed in a mechanical seal gland (14), the mechanical seal gland is fixed on a vacuum pump cavity (8) through a connecting bolt (17) and is sealed by a third 0-shaped rubber ring (9), the sealing friction surface on one side of the dynamic ring and one side of the static ring are in contact to form a mechanical seal friction surface, characterized in that The sealing friction surface of the dynamic ring (6) is processed with bidirectional special curve spiral grooves in the circumferential direction of the inner and outer diameters, which include outer diameter direction special curve spiral grooves (601) and inner diameter direction special curve spiral grooves (602). The outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves symmetrically and equidistantly arranged in pairs at the dynamic ring are converged at one end in the reverse direction of the rotation of the vacuum pump transmission shaft (1). The inner side of the convergence is connected with another outer diameter direction special curve spiral groove and inner diameter direction special curve spiral groove extended from the rear, forming a sealing weir (603) between the outer diameter direction special curve spiral groove and the inner diameter direction special curve spiral groove. When the special curve spiral grooves of the dynamic ring rotate at a high speed synchronously with the vacuum pump transmission shaft, an inward suction force is generated to suck lubricating oil into the sealing friction surface of the dynamic ring to form a liquid film.

2. The mechanical seal assembly of claim 1, wherein The outer diameter direction special curve spiral grooves (601) and the inner diameter direction special curve spiral grooves (602) of the dynamic ring (6) are respectively arranged in an arc shape between the two ends, and the gap between the converging ends of the outer diameter direction special curve spiral grooves and the inner diameter direction special curve spiral grooves is in an arc shape. The sealing weir (603) at the other end is in a triangular shape and is integrally formed on the inner wall of the dynamic ring.

3. A mechanical seal assembly for a vacuum pump outer end axial non-lubricated seal surface according to claim 2, wherein The outer diameter direction special curve spiral grooves (601) and the inner diameter direction special curve spiral grooves (602) of the dynamic ring (6) are respectively arranged in twelve groups symmetrically and equidistantly with the vacuum pump transmission shaft (1) as a circle. One group of outer diameter direction special curve spiral grooves and inner diameter direction special curve spiral grooves are arranged at an angle of 45 degrees between the first and the last with the vacuum pump transmission shaft as a circle.

4. The mechanical seal assembly of claim 1, wherein The dynamic ring (6) and the static ring (7), the mechanical seal shaft sleeve (15) on one side of the dynamic ring, the mechanical seal gland (14) on one side of the static ring, and the shaft sleeve (13) are integrated to form a mechanical seal. The mechanical seal is pushed into the vacuum pump transmission shaft (1), the mechanical seal gland is tightened with the connection bolt (17) of the vacuum pump cavity (8), and the locking screw (10) in the locking ring (11) is locked on the vacuum pump transmission shaft. The locking ring is arranged on the atmospheric side of the vacuum pump oil tank (16).

5. The mechanical seal assembly of claim 1, wherein The outer diameter of the vacuum pump transmission shaft (1) at the other end of the shaft sleeve (13) is provided with an oil throwing disc (2).

6. The mechanical seal assembly of claim 1, wherein The shaft sleeve (13) and the mechanical seal shaft sleeve (15) are sleeved at the outer side of the small spring (5), and a second 0-shaped rubber ring (4) is arranged at the sleeved position. The outer diameter of the vacuum pump transmission shaft (1) at the other end of the shaft sleeve (13) is provided with an oil throwing disc (2).

Images