An adaptive zero-leak seal structure suitable for high pressure gas containment

Abstract

The self-adaptive zero-leakage sealing structure suitable for high-pressure gas sealing comprises a first sealing structure, a second sealing structure and an auxiliary gas sealing structure; a first stepped surface with a gradually decreasing outer diameter is arranged on the outer wall of a main shaft in the axial direction from the low-pressure side to the high-pressure side; the auxiliary gas sealing structure, the first sealing structure and the second sealing structure are arranged on the side of the main shaft provided with the first stepped surface and sequentially arranged from the high-pressure side to the low-pressure side; the first sealing structure comprises a first sealing ring mounting seat and a first sealing ring, and the first sealing ring mounting seat is provided with a second stepped surface capable of forming a first mounting groove with the first stepped surface and the auxiliary gas sealing structure; the second sealing structure comprises a second sealing ring mounting seat and a second sealing ring, and the second sealing ring mounting seat is provided with a third stepped surface capable of forming a second mounting groove with the first stepped surface and the first sealing ring mounting seat; the first sealing ring and the second sealing ring seal the gas flow from the radial and axial directions. The structure can realize zero-leakage sealing of high-pressure gas, improve the working efficiency of the motor and save energy.

Description

Technical Field

[0001] This invention relates to the field of magnetic levitation air compressor technology, and in particular to an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing. Background Technology

[0002] A magnetic levitation air compressor is a high-pressure centrifugal compressor that uses a magnetic levitation motor as its drive and air as its compression medium. With advancements in magnetic levitation motor technology, magnetic levitation air compressors can achieve higher pressure ratios and offer excellent energy savings. An air seal is required between the rotor and stator inside the centrifugal compressor to reduce gas leakage. At low pressures, a non-contact air seal structure is typically used.

[0003] However, the high gas pressure in air compressors leads to an increased pressure difference across the air seal. Traditional labyrinth non-contact seals and carbon ring seals cannot meet the sealing requirements of magnetic levitation air compressors under high pressure. Labyrinth seals cause high-temperature air to leak from the back of the compressor impeller into the motor, affecting motor efficiency. The leaked high-pressure air also results in energy loss, hindering energy conservation. Carbon ring seals suffer from problems such as large installation space requirements and a gradual increase in leakage over time. Summary of the Invention

[0004] This invention provides an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing to solve the above-mentioned problems.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] An adaptive zero-leakage sealing structure suitable for high-pressure gas sealing includes a first sealing structure, a second sealing structure, and an auxiliary gas seal structure;

[0007] The outer wall of the main shaft has a first stepped surface with a gradually decreasing outer diameter along its axial direction and from the low-pressure side to the high-pressure side where the impeller is located; the auxiliary air seal structure, the first sealing structure and the second sealing structure are all located on the side of the main shaft with the first stepped surface and are arranged sequentially from the high-pressure side to the low-pressure side;

[0008] The first sealing structure includes a first sealing ring mounting seat and a first sealing ring sleeved on the first sealing ring mounting seat. The outer ring of the first sealing ring mounting seat is provided with a second stepped surface with a gradually increasing outer diameter along the direction from the high pressure side to the low pressure side. The second stepped surface, the first stepped surface, and the auxiliary gas seal structure can form a first mounting groove for installing the first sealing ring.

[0009] The second sealing structure includes a second sealing ring mounting seat and a second sealing ring sleeved on the second sealing ring mounting seat. The outer ring of the second sealing ring mounting seat is provided with a third stepped surface with a gradually increasing outer diameter along the direction from the high pressure side to the low pressure side, and a second mounting groove for mounting the second sealing ring can be formed between the third stepped surface, the first stepped surface, and the first sealing ring mounting seat.

[0010] The outer ring of the auxiliary air seal structure is provided with air seal teeth on the side facing the outer wall of the motor main shaft for sealing the high-pressure side airflow in the radial direction.

[0011] The first and second sealing rings are capable of sealing the airflow in the radial and axial directions.

[0012] Furthermore, the second stepped surface includes a first L-shaped positioning surface, a first sealing ring radial mounting surface, a first stop, and a first extension surface arranged sequentially from the high-pressure side to the low-pressure side; the first L-shaped positioning surface is used to position the auxiliary gas seal structure;

[0013] A first chip removal groove is provided between the first stop and the radial mounting surface of the first sealing ring, and the first stop, the first chip removal groove and the radial mounting surface of the first sealing ring form a first L-shaped surface;

[0014] The auxiliary air seal structure is provided with an auxiliary air seal structure positioning platform and a left axial stop of the first sealing ring extending from the high pressure side to the low pressure side on the side close to the first sealing structure. The left axial stop of the first sealing ring is arranged opposite to the first stop, and the left axial stop of the first sealing ring is arranged opposite to one wall surface of the first L-shaped positioning surface. The auxiliary air seal structure positioning platform abuts against another wall surface of the first L-shaped positioning surface.

[0015] The first stepped surface of the spindle includes a first sealing ring mounting surface, a first sealing ring chip sealing surface, and a second L-shaped surface arranged sequentially from the high-pressure side to the low-pressure side; the first sealing ring mounting surface is arranged opposite to the first sealing ring radial mounting surface, and the second L-shaped surface is arranged opposite to the first extension surface and has a gap.

[0016] The first sealing ring is disposed in the first mounting groove formed by the first L-shaped surface, the left axial stop of the first sealing ring, the mounting surface of the first sealing ring, and the chip sealing surface of the first sealing ring. The first sealing ring is used to prevent airflow from entering the gap between the second L-shaped surface and the first extended surface. The inner ring of the first sealing ring abuts against the radial mounting surface of the first sealing ring. The right end face of the first sealing ring is always in contact with the chip sealing surface of the first sealing ring. After the spindle has been running for a period of time, under the action of airflow and friction with the spindle, the side of the right end face of the first sealing ring near the radial mounting surface of the first sealing ring can move to abut against the first stop. The first chip groove is used to collect the cutting chips generated by grinding the first sealing ring and the chip sealing surface of the first sealing ring.

[0017] Furthermore, the third stepped surface includes a second L-shaped positioning surface, a second sealing ring radial mounting surface, a second stop, and a second extension surface arranged sequentially from the high-pressure side to the low-pressure side;

[0018] A second chip removal groove is provided between the radial mounting surface of the second sealing ring and the second stop; the second stop, the second chip removal groove, and the radial mounting surface of the second sealing ring form a third L-shaped surface;

[0019] The first stepped surface of the spindle also includes a second sealing ring mounting surface, a second sealing ring chip sealing surface, and a spindle outer peripheral surface, which are sequentially extended from the end of the second L-shaped surface away from the high-pressure side toward the low-pressure side. The second sealing ring mounting surface is arranged opposite to the second sealing ring radial mounting surface, and the spindle outer peripheral surface is arranged opposite to and spaced apart from the second extended surface.

[0020] The first sealing ring mounting base is also provided with a first sealing ring mounting base positioning platform on the side near the low pressure side, which is opposite to the first extension surface. A second stop is provided between the first extension surface and the first sealing ring mounting base positioning platform, and the second stop is opposite to the second sealing ring chip sealing surface.

[0021] The first sealing ring mounting base is positioned on one wall of the second L-shaped positioning surface, and the second stop is positioned opposite to the other wall of the second L-shaped positioning surface.

[0022] The second sealing ring is disposed in the groove formed by the third L-shaped surface, the second stop, the second sealing ring mounting surface, and the second sealing ring chip sealing surface. The second sealing ring is used to block airflow from entering the gap between the outer peripheral surface of the spindle and the second extended surface. The inner ring of the second sealing ring abuts against the radial mounting surface of the second sealing ring. The right end face of the second sealing ring is always in contact with the chip sealing surface of the second sealing ring. When the spindle has been running for a period of time and the right end face of the first sealing ring moves to abut against the first stop, the right side of the second sealing ring and the chip sealing surface of the second sealing ring will wear under the action of airflow and friction with the spindle. The side of the right side of the second sealing ring near the mounting surface of the second sealing ring can move to abut against the second stop. The second chip groove is used to collect the cutting chips generated by the grinding of the second sealing ring and the chip sealing surface of the second sealing ring.

[0023] Furthermore, the axial clearance distance from the left end face of the first sealing ring to the left axial stop of the first sealing ring is a, and the value of a ranges from 0.2 to 0.3 mm.

[0024] The axial clearance distance between the first stop and the chip sealing surface of the first sealing ring is b, and the value of b ranges from 0.2 to 0.3 mm.

[0025] The axial clearance distance from the left end face of the second sealing ring to the second stop is c, and the value of c ranges from 0.2 to 0.3 mm.

[0026] The axial clearance distance between the second stop and the chip sealing surface of the second sealing ring is d, and the value of d ranges from 0.2 to 0.3 mm.

[0027] The axial movement of the main shaft is k, and the value of k ranges from 0.15 to 0.2 mm. The values ​​of a, b, c, and d are all greater than the value of k. Further, the thickness of the first sealing ring is h1, and the length of the first stop is h2, where 20% h1 ≤ h2 ≤ h1.

[0028] The thickness of the second sealing ring is h1', the length of the second stop is h2', and 20% h1'≤h2'≤h1'.

[0029] Furthermore, the first chip removal groove includes a first straight edge and a first arc-shaped part. The first straight edge is a straight wall structure that is gradually arranged radially inward from the right end of the radial mounting surface of the first sealing ring towards the low-pressure side. The high-pressure side of the first straight edge is connected to the radial mounting surface of the first sealing ring, the low-pressure side of the first straight edge is connected to the first arc-shaped part, and the side of the first arc-shaped part away from the first straight edge is connected to the first stop.

[0030] The angle between the first straight edge and the extended surface of the radial mounting surface of the first sealing ring is θ, where θ = 20°;

[0031] The sum of the axial widths of the first straight edge and the first arc-shaped part is g, where g = 0.8 mm.

[0032] Furthermore, the second chip removal groove includes a second straight edge and a second arc-shaped part. The second straight edge is a straight wall structure that is gradually arranged radially inward from the right end of the radial mounting surface of the second sealing ring towards the low-pressure side. The high-pressure side of the second straight edge is connected to the radial mounting surface of the second sealing ring, the low-pressure side of the second straight edge is connected to the second arc-shaped part, and the side of the second arc-shaped part away from the second straight edge is connected to the second stop.

[0033] The angle between the second straight edge and the extended surface of the radial mounting surface of the second sealing ring is θ', where θ' = 20°;

[0034] The sum of the axial widths of the second straight edge and the second arc-shaped part is g', where g' = 0.8 mm.

[0035] Furthermore, the first sealing ring mounting base is provided with a connecting through hole;

[0036] The auxiliary air seal structure is provided with fixing holes;

[0037] The second sealing ring mounting base is provided with a mounting hole; the fastener passes through the fixing hole and the connecting through hole in sequence and extends into the mounting hole to connect the auxiliary air seal structure, the first sealing ring mounting base and the second sealing ring mounting base.

[0038] The beneficial effects of this invention are:

[0039] This invention discloses an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing. The dual-stage seal formed by the first and second sealing structures enables airflow to leak from the high-pressure side to the low-pressure side through the auxiliary gas seal structure during the rotation of the main shaft. After entering the first and second mounting grooves in sequence, the airflow is sealed in both the radial and axial directions, preventing high-temperature air from leaking from the back of the compressor impeller into the motor. This achieves zero-leakage sealing of high-pressure gas, improves the working efficiency of the motor, avoids energy loss caused by air leakage, and is economical and energy-saving. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a front sectional view of an adaptive zero-leakage seal suitable for high-pressure gas sealing disclosed in an embodiment of the present invention;

[0042] Figure 2 for Figure 1 Enlarged view of section A;

[0043] Figure 3 This is a front sectional view of the first sealing ring mounting base of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention.

[0044] Figure 4 for Figure 3 Enlarged view of section B;

[0045] Figure 4 This invention discloses an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing.

[0046] Figure 5 This is a front sectional view of the second sealing ring mounting base of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention.

[0047] Figure 6 for Figure 5 Enlarged view of section C;

[0048] Figure 7 This is a front sectional view of the main shaft of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention.

[0049] Figure 8 This is a front sectional view of an auxiliary gas seal structure for an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing, disclosed in an embodiment of the present invention.

[0050] Figure 9 This is a front sectional view of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention, labeled a, b, c, and d.

[0051] Figure 10 for Figure 9 Enlarged view of section D;

[0052] Figure 11 This is a schematic diagram of the first chip removal groove structure of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention;

[0053] Figure 12 This is a front sectional view of the first sealing ring of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention.

[0054] Figure 13 This is a schematic diagram showing the positions of the first and second sealing rings after a period of operation of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention.

[0055] Figure 14 This is a schematic diagram showing the positions of the first and second sealing rings after a long period of operation of an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing disclosed in an embodiment of the present invention.

[0056] In the picture:

[0057] 1. Auxiliary air seal structure; 11. Air seal teeth; 12. Axial stop on the left side of the first sealing ring; 13. Positioning platform for the auxiliary air seal structure; 14. Fixing hole;

[0058] 2. First sealing ring;

[0059] 3. First sealing ring mounting base; 31. First stop; 32. First chip removal groove; 321. First straight edge; 322. First arc-shaped part; 33. First sealing ring radial mounting surface; 34. First L-shaped positioning surface; 35. Second stop; 36. First sealing ring mounting base positioning platform; 37. Connecting through hole; 38. First extension surface;

[0060] 4. Gaskets;

[0061] 5. Second sealing ring mounting seat; 51. Second stop; 52. Second chip removal groove; 521. Second straight edge; 522. Second arc-shaped part; 53. Second sealing ring radial mounting surface; 54. Second L-shaped positioning surface; 55. Mounting hole; 56. Second sealing ring seat mounting through hole; 57. Second extension surface;

[0062] 6. Second sealing ring;

[0063] 7. Spindle; 71. First seal ring mounting surface; 72. First seal ring chip sealing surface; 73. Second seal ring mounting surface; 74. Second seal ring chip sealing surface; 75. Second L-shaped surface; 76. Outer circumferential surface of the spindle;

[0064] 8. First mounting slot;

[0065] 9. First mounting slot. Detailed Implementation

[0066] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0067] like Figure 1-2 The figure shown is an adaptive zero-leakage sealing structure (initial installation state) suitable for high-pressure gas sealing provided in this embodiment, including a first sealing structure, a second sealing structure and an auxiliary gas seal structure 1;

[0068] The outer wall of the main shaft 7 has a first stepped surface with a gradually decreasing outer diameter along its axial direction and from the low-pressure side to the high-pressure side where the impeller is located; the auxiliary air seal structure 1, the first sealing structure and the second sealing structure are all located on the side of the main shaft where the first stepped surface is located and are arranged sequentially along the high-pressure side to the low-pressure side.

[0069] The first sealing structure includes a first sealing ring mounting base 3 and a first sealing ring 2 sleeved on the first sealing ring mounting base 3. The outer ring of the first sealing ring mounting base 3 is provided with a second stepped surface with a gradually increasing outer diameter along the direction from the high pressure side to the low pressure side, and a first mounting groove 8 for mounting the first sealing ring 2 can be formed between the second stepped surface, the first stepped surface, and the auxiliary gas seal structure 1.

[0070] The second sealing structure includes a second sealing ring mounting seat 5 and a second sealing ring 6 sleeved on the second sealing ring mounting seat. The outer ring of the second sealing ring mounting seat is provided with a third stepped surface with a gradually increasing outer diameter along the direction from the high pressure side to the low pressure side. The third stepped surface, the first stepped surface, and the first sealing ring mounting seat 3 can form a second mounting groove 9 for mounting the second sealing ring 6.

[0071] like Figure 8 As shown, the outer ring of the auxiliary air seal structure 1 is provided with air seal teeth 11 on the side facing the outer wall of the motor main shaft for sealing the high-pressure side airflow in the radial direction;

[0072] The first sealing ring 2 and the second sealing ring 6 can seal the airflow in the radial and axial directions. In this embodiment, both the first sealing ring 2 and the second sealing ring 6 are metal sealing rings. Metal sealing rings have the advantages of simple structure, convenient installation and reliable sealing performance, which are more suitable for this sealing structure. The diameter of the second sealing ring 6 is larger than the diameter of the first sealing ring 2.

[0073] This invention discloses an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing. The dual-stage seal formed by the first and second sealing structures enables the airflow to leak from the high-pressure side to the low-pressure side through the auxiliary gas seal structure during the rotation of the main shaft. After entering the first and second mounting grooves in sequence, the airflow is sealed in both the radial and axial directions, preventing high-temperature air from leaking from the back of the compressor impeller into the motor. This achieves zero-leakage sealing of high-pressure gas, improves the working efficiency of the motor, avoids energy loss caused by air leakage, and is more economical and energy-saving.

[0074] Meanwhile, this sealing structure eliminates the need to install the sealing ring on the spindle first and then install the sealing ring mounting base. Instead, all components of the sealing structure are assembled first, and then the sealing structure is installed on the spindle. This structure avoids positional interference with the sealing ring already installed on the spindle when installing the sealing ring mounting base, thus preventing the sealing ring from shifting and resulting in poor sealing performance.

[0075] In a specific embodiment, the second stepped surface includes a first L-shaped positioning surface 34, a first sealing ring radial mounting surface 33, a first stop 31, and a first extension surface 38 arranged sequentially from the high-pressure side to the low-pressure side; the first L-shaped positioning surface 34 is used to position the auxiliary air seal structure 1.

[0076] like Figure 3 , Figure 4 As shown, a first chip removal groove 32 is provided between the first stop 31 and the radial mounting surface 33 of the first sealing ring, and the first stop 31, the first chip removal groove 32 and the radial mounting surface 33 of the first sealing ring form a first L-shaped surface;

[0077] The auxiliary air seal structure 1 is provided with an auxiliary air seal structure positioning platform 13 and a left axial stop 12 of the first sealing ring extending from the high pressure side to the low pressure side on the side close to the first sealing structure. The left axial stop 12 of the first sealing ring is opposite to the first stop 31, and the left axial stop 12 of the first sealing ring is opposite to one wall surface on the first L-shaped positioning surface 34. The auxiliary air seal structure positioning platform 13 abuts against the other wall surface on the first L-shaped positioning surface 34.

[0078] like Figure 7 As shown, the first stepped surface of the spindle 7 includes a first sealing ring mounting surface 71, a first sealing ring chip sealing surface 72, and a second L-shaped surface 75 arranged sequentially from the high-pressure side to the low-pressure side; the first sealing ring mounting surface 71 is arranged opposite to the first sealing ring radial mounting surface 33, and the second L-shaped surface 75 is arranged opposite to the first extension surface 38 and has a gap.

[0079] The first sealing ring 2 is disposed in the first mounting groove 8 formed by the first L-shaped surface, the left axial stop 12 of the first sealing ring, the mounting surface 71 of the first sealing ring, and the chip sealing surface 72 of the first sealing ring. The first sealing ring 2 is used to seal the airflow entering the first mounting groove from the axial and radial directions to prevent the airflow from entering the gap between the second L-shaped surface 75 and the first extension surface 38. The inner ring of the first sealing ring abuts against the radial mounting surface 33 of the first sealing ring (that is, the first sealing ring is sleeved on the radial mounting surface 33 of the first sealing ring of the first sealing ring mounting seat 3). The right end face (low pressure side) of the first sealing ring 2 is always in contact with the chip sealing surface 72 of the first sealing ring. After the spindle has been running for a period of time, under the action of airflow and friction with the spindle, the side of the right end face of the first sealing ring close to the radial mounting surface 33 of the first sealing ring can move to abut against the first stop 31. The first chip groove 32 is used to collect the cutting chips generated by the grinding of the first sealing ring and the chip sealing surface 72 of the first sealing ring.

[0080] Specifically, when the main shaft rotates and the airflow enters the first mounting groove 8 through the air seal tooth 11, the first sealing ring 2 can block the airflow from entering the gap between the first extension surface 38 and the second L-shaped surface 75. As the centrifugal compressor works and the main shaft rotates, the right end face of the first sealing ring and the chip sealing surface 72 of the first sealing ring will wear. Under the action of the airflow pressure entering the first mounting groove 8 through the air seal tooth, the wear between the right end face of the first sealing ring and the chip sealing surface 72 of the first sealing ring will gradually increase. During this process, the first sealing ring gradually moves towards the low-pressure side in the first mounting groove 8 until the part of the right end face of the first sealing ring close to the radial mounting surface 33 of the first sealing ring (i.e., the part of the right end face of the first sealing ring that does not abut against the chip sealing surface 72 of the first sealing ring) can move to abut against the first stop 31. At this time, both are in a static state, realizing the radial and axial sealing of the airflow. The small amount of cutting chips generated enters the first chip discharge groove 32, which can prevent the cutting chips from affecting the normal operation of subsequent equipment.

[0081] In a specific embodiment, such as Figure 5 , Figure 6 As shown, the third stepped surface includes a second L-shaped positioning surface 54, a second sealing ring radial mounting surface 53, a second stop 51, and a second extension surface 57 arranged sequentially from the high-pressure side to the low-pressure side.

[0082] A second chip removal groove 52 is provided between the radial mounting surface 53 of the second sealing ring and the second stop 51; the second stop 51, the second chip removal groove 52, and the radial mounting surface 53 of the second sealing ring form a third L-shaped surface.

[0083] The first stepped surface of the main spindle 7 also includes a second sealing ring mounting surface 73, a second sealing ring chip sealing surface 74, and a main spindle outer peripheral surface 76, which are sequentially extended from the end of the second L-shaped surface 75 away from the high pressure side toward the low pressure side. The second sealing ring mounting surface 73 is arranged opposite to the second sealing ring radial mounting surface 53, and the main spindle outer peripheral surface 76 is arranged opposite to and spaced apart from the second extension surface 57.

[0084] The first sealing ring mounting base 3 is also provided with a first sealing ring mounting base positioning platform 36 on the side near the low pressure side, which is opposite to the first extension surface 38. A second stop 35 is provided between the first extension surface 38 and the first sealing ring mounting base positioning platform 36. The second stop 35 is opposite to the second sealing ring chip sealing surface 74.

[0085] The first sealing ring mounting base positioning platform 36 abuts against one wall of the second L-shaped positioning surface 54, and the second stop 35 is set opposite to the other wall of the second L-shaped positioning surface 54;

[0086] The second sealing ring 6 is disposed in the second sealing ring groove 9 formed by the third L-shaped surface, the second stop 35, the second sealing ring mounting surface 73, and the second sealing ring chip sealing surface 74. The second sealing ring 6 is used to seal the airflow entering the second mounting groove from the axial and radial directions to prevent the airflow from entering the gap between the outer peripheral surface 76 of the spindle and the second extension surface 57. The inner ring of the second sealing ring abuts against the radial mounting surface 53 of the second sealing ring. The right end face (low pressure side) of the second sealing ring is always in contact with the chip sealing surface 74 of the second sealing ring. When the spindle runs for a period of time and the right end face of the first sealing ring moves to abut against the first stop 31, the right side of the second sealing ring and the chip sealing surface 74 of the second sealing ring are worn under the action of airflow and friction with the spindle. The side of the right side of the second sealing ring near the second sealing ring mounting surface 73 can move to abut against the second stop 51. The second chip groove 52 is used to collect the cutting chips generated by the grinding of the second sealing ring and the chip sealing surface 74 of the second sealing ring.

[0087] Specifically, after the right end face of the first sealing ring moves to abut against the first stop 31, as the spindle continues to rotate, since the first sealing ring may not completely block all the airflow, some airflow will enter the second mounting groove through the gap between the second L-shaped surface 75 and the first extended surface 38. The second sealing ring 6 can prevent airflow from entering the gap between the outer peripheral surface 76 of the spindle and the second extended surface 57. As the spindle rotates, the right end face of the second sealing ring and the chip sealing surface 74 of the second sealing ring will wear. Under the action of the airflow pressure entering the second mounting groove 9, the wear between the right end face of the second sealing ring and the chip sealing surface 74 of the second sealing ring will gradually increase. During this process, the second sealing ring in the second mounting groove 9... The inner part gradually moves towards the low-pressure side until the part of the right end face of the second sealing ring near the radial mounting surface 53 of the second sealing ring (i.e., the part of the right end face of the second sealing ring that does not abut against the chip sealing surface 74 of the second sealing ring) can move to abut against the second stop 51. At this time, both are in a static state. The second sealing ring achieves a seal against the airflow from the radial and axial directions. The small amount of cutting chips generated enters into the second chip discharge groove 52, which can prevent the cutting chips from affecting the normal operation of subsequent equipment. The cooperation between the second sealing structure and the first sealing structure can achieve a zero-leakage seal for high-pressure gas. In this embodiment, the second sealing ring mounting base 5 is also provided with a second sealing ring mounting through hole 56 for the second sealing ring mounting base 5 to achieve a detachable connection with other components.

[0088] In a specific embodiment, such as Figure 9 , Figure 10 As shown, the axial clearance distance from the left end face of the first sealing ring 2 (the side end face near the first sealing ring mounting base 3) to the left axial stop 12 of the first sealing ring is a, and the value of a ranges from 0.2 to 0.3 mm.

[0089] The axial clearance distance between the first stop 31 and the first sealing ring chip sealing surface 72 is b, and the value of b ranges from 0.2 to 0.3 mm.

[0090] The axial clearance distance from the left end face of the second sealing ring 6 (the end face near the auxiliary air seal structure 1) to the second stop 35 is c, and the value of c ranges from 0.2 to 0.3 mm.

[0091] The axial clearance distance between the second stop 51 and the chip sealing surface 74 of the second sealing ring is d, and the value of d ranges from 0.2 to 0.3 mm.

[0092] The axial movement of the main shaft is k, and the value of k ranges from 0.15 to 0.2 mm. The values ​​of a, b, c, and d are all greater than the value of k. The value of k depends on the axial single-sided protection clearance of the magnetic levitation motor, which is usually within the range of 0.15 to 0.2 mm. The values ​​of a, b, c, and d are set to the same value and need to be greater than the axial movement of the main shaft k. In this embodiment, the value of k is 0.2 mm, and the values ​​of a, b, c, and d are all set to 0.25 mm to ensure that the axial movement of the compressor is not restricted during operation, while ensuring effective sealing, so that this sealing structure can achieve zero leakage sealing for high-pressure gas. The width e of the first sealing ring is as follows: Figure 12 As shown, the structure of the second sealing ring is the same as that of the first sealing ring, which can be referred to. Figure 12 The width e of the first sealing ring and the width e' of the second sealing ring are both set to 3mm. The width of the first mounting groove is f = e + a = 0.25 + 3 = 5mm, and the width of the second mounting groove is f' = e' + c = 0.25 + 3 = 5mm.

[0093] In a specific embodiment, the thickness of the first sealing ring 2 is h1, the length of the first stop 31 is h2, and 20% h1≤h2≤h1;

[0094] The thickness of the second sealing ring 6 is h1', and the length of the second stop 51 is h2', where 20% h1' ≤ h2' ≤ h1'; taking the first sealing ring as an example, the initial state of this structure is as follows: Figure 1 , Figure 2 As shown, when the compressor is working, as the main shaft rotates, the first sealing ring will first experience wear between itself and the first sealing ring chip sealing surface of the main shaft. Under the action of high-pressure airflow, the first sealing ring will move towards the low-pressure side until the upper right end face of the first sealing ring abuts against the first stop 31. Figure 13As shown, the first sealing ring stops moving under the action of the first stop, and both are in a stationary state. At this time, the first sealing ring forms a seal against the airflow in both the axial and radial directions. Setting the length h2 of the first stop within the range of 20%h1≤h2≤h1 ensures the stopping effect on the first sealing ring and guarantees the stable limitation of its position. The sealing process and principle of the second sealing ring are the same as those of the first sealing ring, as follows... Figure 14 The diagram shows the position of the second sealing ring when it moves to abut against the second stop. In this embodiment, the length h2 of the first stop is set to 0.5 mm, the thickness h1 of the first sealing ring is set to 2.2 mm, the length h2' of the second stop is set to 0.7 mm, and the thickness h1' of the second sealing ring is set to 2.8 mm.

[0095] In a specific embodiment, such as Figure 11 As shown, the first chip removal groove 32 includes a first straight edge portion 321 and a first arc-shaped portion 322. The first straight edge portion 321 is a straight wall structure that is gradually arranged radially inward from the right end of the radial mounting surface 33 of the first sealing ring towards the low-pressure side. The high-pressure side of the first straight edge portion 321 is connected to the radial mounting surface 33 of the first sealing ring, and the low-pressure side of the first straight edge portion 321 is connected to the first arc-shaped portion 322. The side of the first arc-shaped portion away from the first straight edge portion 321 is connected to the first stop 31.

[0096] The angle between the first straight edge 321 and the extended surface of the radial mounting surface 33 of the first sealing ring is θ, where θ = 20°;

[0097] The sum of the axial widths of the first straight edge and the first arc-shaped part 322 is g, where g = 0.8 mm. That is, g is the straight distance from the right end face of the radial mounting surface 33 of the first sealing ring to the left end face of the first extension surface 38. In other words, the width of the second chip removal groove 52 is set to 0.8 mm, and θ is set to 20° to facilitate the entry of the cutting chips generated by the grinding of the first sealing ring and the first sealing ring cutting sealing surface into the first chip removal groove.

[0098] In a specific embodiment, the second chip discharge groove 52 includes a second straight edge portion 521 and a second arc-shaped portion 522. The second straight edge portion 521 is a straight wall structure that is gradually arranged radially inward from the right end of the radial mounting surface 53 of the second sealing ring towards the low-pressure side. The high-pressure side of the second straight edge portion 521 is connected to the radial mounting surface 53 of the second sealing ring, and the low-pressure side of the second straight edge portion 521 is connected to the second arc-shaped portion 522. The side of the second arc-shaped portion away from the second straight edge portion 521 is connected to the second stop 51.

[0099] The angle between the second straight edge 521 and the extended surface of the radial mounting surface 53 of the second sealing ring is θ', where θ' = 20°;

[0100] The sum of the axial widths of the second straight edge portion 521 and the second arc-shaped portion 522 is g', where g' = 0.8 mm. This means g' is the straight-line distance from the right end face of the radial mounting surface 53 of the second sealing ring to the left end face of the second extension surface 57. In other words, the width of the second chip removal groove 52 is set to 0.8 mm to facilitate the entry of cutting chips generated during grinding between the second sealing ring and the chip sealing surface into the second chip removal groove 52. The shape and structure of the second chip removal groove 52 are consistent with the first chip removal groove, which can be referenced. Figure 11 The structure of the first chip removal groove.

[0101] In a specific embodiment, the first sealing ring mounting base 3 is provided with a connecting through hole 37;

[0102] The auxiliary air seal structure 1 is provided with a fixing hole 14;

[0103] The second sealing ring mounting base 5 is provided with a mounting hole 55; the fixing member passes through the fixing hole 14 and the connecting through hole 37 in sequence and extends into the mounting hole 55 to connect the auxiliary air seal structure 1, the first sealing ring mounting base 3 and the second sealing ring mounting base 5; during installation, the first sealing ring can be directly installed on the first sealing ring mounting base 3, the second sealing ring can be installed on the second sealing ring mounting base, and then the auxiliary air seal structure can be fixedly connected to the first sealing ring mounting base and the second sealing ring mounting base with bolts to form an integral sealing structure. Finally, the integral sealing structure can be installed on the spindle. Compared with the existing technology, which requires the sealing ring to be installed on the spindle first and then the sealing ring mounting base to be installed, this sealing structure can avoid positional interference of the sealing ring already installed on the spindle when installing the sealing ring mounting base, so as to avoid the problem of poor sealing effect caused by the positional displacement of the sealing ring.

[0104] In a specific embodiment, a gasket 4 is provided between the auxiliary air seal structure 1 and the first sealing ring mounting seat 3. By setting gaskets of different thicknesses, the values ​​of a, b, c, and d can be adjusted to meet the actual usage requirements.

[0105] The present invention discloses an adaptive zero-leakage sealing structure suitable for high-pressure gas sealing, the working process of which is as follows:

[0106] When the air compressor impeller rotates, high-pressure air leaks downwards from the back of the impeller. It first passes through the air seal teeth 11 for initial radial sealing. The remaining high-pressure gas continues to leak to the right. The high pressure causes the first sealing ring 2 to move towards the low-pressure side, i.e., the right side. The first sealing ring will first contact the first sealing ring chip sealing surface 72. Since the main shaft is a rotating component and the sealing ring is a stationary component, their interaction will grind the right end face of the first sealing ring. After further grinding, the corresponding position of the first sealing ring and the first sealing ring chip sealing surface will be worn away, and the upper part of the first sealing ring will contact the first stop 31. At this point, both are stationary, so no grinding occurs. The entire radial and axial direction is then blocked by the first sealing ring, thus achieving a seal. To ensure a tight seal, a second sealing ring is also provided on the right side of the first sealing ring. If high-pressure gas leaks in, the second sealing ring will achieve the same sealing effect as the first sealing ring.

[0107] The installation features of this sealing structure are as follows: Conventional installation of the sealing ring requires installing it within the sealing groove of the spindle before installing the sealing seat. Because the sealing ring is generally elastic, its outer diameter is larger than the sealing seat, leading to installation difficulties and even damage. Furthermore, since the assembly personnel cannot see the sealing ring during installation, they cannot detect whether it has been damaged. This structure uses a combined sealing groove structure, with the first and second sealing rings made in two different diameters. This allows the sealing ring to be installed directly on the sealing seat first, followed by the assembly of the sealing seat with the sealing ring. Since the inner diameter of the sealing ring is larger than the diameter of the sealing groove on the spindle, the problems of difficult installation and seal damage are avoided. During assembly, the first and second sealing structures are assembled separately first, then the second sealing structure, the first sealing structure, and the auxiliary air seal structure are sequentially fitted onto the spindle. To ensure that values ​​a, b, c, and d meet the requirements, shims 4 can be added between the sealing structures.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An adaptive zero-leakage sealing structure suitable for high-pressure gas sealing, characterized in that, It includes a first sealing structure, a second sealing structure, and an auxiliary air seal structure (1); The outer wall of the main shaft (7) has a first stepped surface with a gradually decreasing outer diameter along its axial direction and from the low-pressure side to the high-pressure side where the impeller is located; the auxiliary air seal structure (1), the first sealing structure and the second sealing structure are all located on the side of the main shaft where the first stepped surface is located and are arranged sequentially along the high-pressure side to the low-pressure side. The first sealing structure includes a first sealing ring mounting seat (3) and a first sealing ring (2) sleeved on the first sealing ring mounting seat (3). The outer ring of the first sealing ring mounting seat (3) is provided with a second stepped surface with a gradually decreasing outer diameter along the direction from the high pressure side to the low pressure side. The second stepped surface, the first stepped surface, and the auxiliary gas seal structure (1) can form a first mounting groove (8) for installing the first sealing ring (2). The second sealing structure includes a second sealing ring mounting seat (5) and a second sealing ring (6) sleeved on the second sealing ring mounting seat. The outer ring of the second sealing ring mounting seat (5) is provided with a third stepped surface with a gradually decreasing outer diameter along the direction from the high pressure side to the low pressure side. A second mounting groove (9) for installing the second sealing ring (6) can be formed between the third stepped surface, the first stepped surface, and the first sealing ring mounting seat (3). The auxiliary air seal structure (1) has air seal teeth (11) on the side of the outer ring facing the outer wall of the motor main shaft for sealing the high-pressure side airflow in the radial direction. The first sealing ring (2) and the second sealing ring (6) are capable of sealing the airflow in the radial and axial directions; The second stepped surface includes a first L-shaped positioning surface (34), a first sealing ring radial mounting surface (33), a first stop (31), and a first extension surface (38) arranged sequentially from the high-pressure side to the low-pressure side; the first L-shaped positioning surface (34) is used to position the auxiliary air seal structure (1); A first chip removal groove (32) is provided between the first stop (31) and the radial mounting surface (33) of the first sealing ring, and the first stop (31), the first chip removal groove (32) and the radial mounting surface (33) of the first sealing ring form a first L-shaped surface; After the spindle has been running for a period of time, under the action of airflow and friction with the spindle, the side of the right end face of the first sealing ring that is close to the radial mounting surface (33) of the first sealing ring can move to abut against the first stop (31).

2. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 1, characterized in that, The auxiliary air seal structure (1) is provided with an auxiliary air seal structure positioning platform (13) and a left axial stop (12) of the first sealing ring extending from the high pressure side to the low pressure side on the side close to the first sealing structure. The left axial stop (12) of the first sealing ring is arranged opposite to the first stop (31), and the left axial stop (12) of the first sealing ring is arranged opposite to one wall surface on the first L-shaped positioning surface (34). The auxiliary air seal structure positioning platform (13) abuts against the other wall surface on the first L-shaped positioning surface (34). The first stepped surface of the main shaft (7) includes a first sealing ring mounting surface (71), a first sealing ring chip sealing surface (72), and a second L-shaped surface (75) arranged sequentially from the high-pressure side to the low-pressure side; the first sealing ring mounting surface (71) is arranged opposite to the first sealing ring radial mounting surface (33), and the second L-shaped surface (75) is arranged opposite to the first extension surface (38) and has a gap; The first sealing ring (2) is disposed in the first mounting groove (8) formed by the first L-shaped surface, the left axial stop (12) of the first sealing ring, the mounting surface (71) of the first sealing ring, and the chip sealing surface (72) of the first sealing ring. The first sealing ring (2) is used to block the airflow from entering the gap between the second L-shaped surface (75) and the first extension surface (38). The right end face of the first sealing ring (2) is always in contact with the chip sealing surface (72) of the first sealing ring. The first chip groove (32) is used to collect the cutting chips generated by grinding the first sealing ring and the chip sealing surface (72) of the first sealing ring.

3. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 2, characterized in that, The third stepped surface includes a second L-shaped positioning surface (54), a second sealing ring radial mounting surface (53), a second stop (51), and a second extension surface (57) arranged sequentially from the high-pressure side to the low-pressure side. A second chip removal groove (52) is provided between the radial mounting surface (53) of the second sealing ring and the second stop (51); the second stop (51), the second chip removal groove (52), and the radial mounting surface (53) of the second sealing ring form a third L-shaped surface; The first stepped surface of the main shaft (7) also includes a second sealing ring mounting surface (73), a second sealing ring chip sealing surface (74), and a main shaft outer peripheral surface (76) that extend sequentially from the end of the second L-shaped surface (75) away from the high pressure side toward the low pressure side. The second sealing ring mounting surface (73) is opposite to the second sealing ring radial mounting surface (53), and the main shaft outer peripheral surface (76) is opposite to and spaced apart from the second extension surface (57). The first sealing ring mounting base (3) is also provided with a first sealing ring mounting base positioning platform (36) on the side near the low pressure side, which is opposite to the first extension surface (38). A second stop (35) is provided between the first extension surface (38) and the first sealing ring mounting base positioning platform (36). The second stop (35) is opposite to the second sealing ring chip sealing surface (74). The first sealing ring mounting base positioning platform (36) abuts against one wall of the second L-shaped positioning surface (54), and the second stop (35) is set opposite to the other wall of the second L-shaped positioning surface (54); The second sealing ring (6) is located in the second mounting groove (9) formed by the third L-shaped surface, the second stop (35), the second sealing ring mounting surface (73), and the second sealing ring chip sealing surface (74). The second sealing ring (6) is used to block the airflow from entering the gap between the outer peripheral surface (76) of the spindle and the second extension surface (57). The right end face of the second sealing ring is always in contact with the chip sealing surface (74) of the second sealing ring. When the spindle runs for a period of time and the right end face of the first sealing ring moves to contact the first stop (31), the right side of the second sealing ring and the chip sealing surface (74) of the second sealing ring are worn under the action of airflow and friction with the spindle. The side of the right side of the second sealing ring close to the second sealing ring mounting surface (73) can move to contact the second stop (51). The second chip groove (52) is used to collect the cutting chips generated by the grinding of the second sealing ring and the chip sealing surface (74).

4. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 3, characterized in that, The axial clearance distance from the left end face of the first sealing ring (2) to the left axial stop (12) of the first sealing ring is a, and the value range of a is 0.2~0.3mm; The axial clearance distance between the first stop (31) and the first sealing ring chip sealing surface (72) is b, and the value range of b is 0.2~0.3mm; The axial clearance distance from the left end face of the second sealing ring (6) to the second stop (35) is c, and the value range of c is 0.2~0.3mm; The axial clearance distance between the second stop (51) and the chip sealing surface (74) of the second sealing ring is d, and the value range of d is 0.2~0.3mm; The axial movement of the spindle is k, and the value of k ranges from 0.15 to 0.2 mm. The values ​​of a, b, c, and d are all greater than the value of k.

5. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 3, characterized in that, The thickness of the first sealing ring (2) is h1, and the length of the first stop (31) is h2, with 20% h1≤h2≤h1; The thickness of the second sealing ring (6) is h1', and the length of the second stop (51) is h2', with 20% h1'≤h2'≤h1'.

6. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 2, characterized in that, The first chip removal groove (32) includes a first straight edge (321) and a first arc-shaped part (322). The first straight edge (321) is a straight wall structure that is gradually arranged radially inward from the right end of the radial mounting surface (33) of the first sealing ring towards the low-pressure side. The high-pressure side of the first straight edge (321) is connected to the radial mounting surface (33) of the first sealing ring, and the low-pressure side of the first straight edge (321) is connected to the first arc-shaped part (322). The side of the first arc-shaped part away from the first straight edge (321) is connected to the first stop (31). The angle between the first straight edge (321) and the extended surface of the radial mounting surface (33) of the first sealing ring is θ, where θ = 20°; The sum of the axial widths of the first straight edge and the first arc-shaped part (322) is g, where g = 0.8 mm.

7. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 3, characterized in that, The second chip removal groove (52) includes a second straight edge (521) and a second arc-shaped part (522). The second straight edge (521) is a straight wall structure that is gradually arranged radially inward from the right end of the radial mounting surface (53) of the second sealing ring towards the low-pressure side. The high-pressure side of the second straight edge (521) is connected to the radial mounting surface (53) of the second sealing ring, and the low-pressure side of the second straight edge (521) is connected to the second arc-shaped part (522). The side of the second arc-shaped part away from the second straight edge (521) is connected to the second stop (51). The angle between the second straight edge (521) and the extended surface of the radial mounting surface (53) of the second sealing ring is θ', where θ' = 20°; The sum of the axial widths of the second straight edge portion (521) and the second arc-shaped portion (522) is g', where g' = 0.8 mm.

8. The adaptive zero-leakage sealing structure suitable for high-pressure gas sealing according to claim 1, characterized in that, The first sealing ring mounting base (3) is provided with a connecting through hole (37); The auxiliary air seal structure (1) is provided with a fixing hole (14); The second sealing ring mounting base (5) is provided with a mounting hole (55); the fastener passes through the fixing hole (14) and the connecting through hole (37) in sequence and extends into the mounting hole (55) to connect the auxiliary air seal structure (1), the first sealing ring mounting base (3) and the second sealing ring mounting base (5).

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