A low-speed cross-medium rotary sealing device

Abstract

The present invention discloses a low-speed cross-medium rotating sealing device, comprising a fixed shell, a connecting seat, a static ring, a low-pressure dynamic ring, a medium-pressure dynamic ring, a high-pressure dynamic ring and a control disk; the connecting seat is synchronously rotated and connected with the main shaft, the static ring is fixedly arranged in the fixed shell and is provided with a static ring sealing ring; the three dynamic rings are respectively arranged on the connecting seat through three elastic members with different elastic forces and are each provided with a sealing ring at one end, and the sealing ring can respectively abut against the static ring sealing ring; the control disk is connected to the medium-pressure dynamic ring and the high-pressure dynamic ring, and can respectively control the movement of the medium-pressure dynamic ring and the high-pressure dynamic ring relative to the connecting seat, and change the abutment relationship between the corresponding sealing ring and the static ring sealing ring. The low-speed cross-medium rotating sealing device can select dynamic rings with different sealing pressures to work with the help of the control disk at different underwater depths, thereby forming an optimal sealing pressure, reducing torque consumption, and extending the service life of the sealing ring.

Description

Technical Field

[0001] The invention relates to the technical field of sealing devices, and in particular to a low-speed cross-medium rotating sealing device. Background Art

[0002] A sealing device is a device or component used to prevent fluid leakage or prevent foreign substances from entering a specific area. It is widely used in various fields such as petrochemicals, oil and gas transportation, nuclear power, electricity, hydropower, pharmaceuticals, metallurgy, food, ships, aerospace, and military industry.

[0003] In the existing technology, the sealing device is generally composed of a dynamic ring and a static ring supported by a spring. When the sealing device is working, a liquid film will be formed between the static ring and the dynamic ring, thereby realizing the sealing effect. A low-speed cross-medium rotating sealing device is a type of sealing device, which is generally used in hydraulic motors operating underwater. In order to make the hydraulic motor obtain a larger torque, the hydraulic motor needs to maintain a low-speed rotation. In order to prevent water from entering the interior of the hydraulic motor from the main shaft, a low-speed cross-medium rotating sealing device is required between the main shaft and the housing.

[0004] However, the sealing pressure of the existing low-speed cross-medium rotary sealing device cannot be adjusted. Since the water pressure at different underwater depths is different, in order to adapt to the deepest underwater pressure, it is necessary to select a low-speed cross-medium rotary sealing device with a higher sealing pressure. This causes the low-speed cross-medium rotary sealing device to consume a large amount of torque when the hydraulic motor is working, and due to the high pressure on the sealing ring, it will also cause excessive wear of the sealing ring, affecting the service life of the low-speed cross-medium rotary sealing device. Summary of the invention

[0005] In view of the above problems, the present invention proposes a low-speed cross-medium rotary sealing device to overcome the above problems or at least partially solve the above problems.

[0006] A low-speed cross-medium rotating sealing device comprises a fixed shell, a connecting seat, a static ring, a low-pressure dynamic ring, a medium-pressure dynamic ring, a high-pressure dynamic ring and a control disk; the connecting seat is located in the fixed shell, and is connected to a main shaft sleeve that maintains a gap and passes through the fixed shell for synchronous rotation; the static ring is fixedly arranged in the fixed shell, and a static ring sealing ring is provided at one end facing the connecting seat; the low-pressure dynamic ring is movably arranged on the connecting seat along the axial direction of the main shaft through a low-pressure elastic member, and a low-pressure sealing ring is provided in the low-pressure dynamic ring at one end facing the static ring, and the low-pressure elastic member can drive the low-pressure dynamic ring to move until the low-pressure sealing ring abuts against the static ring sealing ring; the medium-pressure dynamic ring is movably arranged on the connecting seat along the axial direction of the main shaft through a medium-pressure elastic member, and a medium-pressure dynamic ring is provided at one end facing the static ring The medium-pressure elastic member can drive the medium-pressure dynamic ring to move until the medium-pressure sealing ring abuts against the static ring sealing ring; the high-pressure dynamic ring is movably arranged on the connecting seat along the axial direction of the main shaft through the high-pressure elastic member, and a high-pressure sealing ring is provided at one end of the high-pressure dynamic ring facing the static ring, and the high-pressure elastic member can drive the high-pressure dynamic ring to move until the high-pressure sealing ring abuts against the static ring sealing ring; the control disk is connected to the medium-pressure dynamic ring and the high-pressure dynamic ring, and can cooperate with the medium-pressure elastic member and the high-pressure elastic member to respectively control the movement of the medium-pressure dynamic ring and the high-pressure dynamic ring relative to the connecting seat, and change the abutting relationship between the medium-pressure sealing ring and the high-pressure sealing ring and the static ring sealing ring; the elastic forces of the low-pressure elastic member, the medium-pressure elastic member and the high-pressure elastic member are different.

[0007] Preferably, the control disk is capable of rotating relative to the connecting seat, and the control disk is provided with a first arc groove and a second arc groove connected in a circumferential direction, and a third arc groove and a fourth arc groove connected in a circumferential direction; the width of the second arc groove is greater than the width of the first arc groove, and a first inclined surface with an inclined transition in a depth direction is provided between the two; the width of the fourth arc groove is greater than the width of the third arc groove, and a second inclined surface with an inclined transition in a depth direction is provided between the two; the other end of the intermediate pressure dynamic ring passes through the first arc groove and is provided with a first limit block, and the width dimension of the first limit block is between the width dimension of the first arc groove and the width dimension of the second arc groove sizes, the rotation of the control disk can drive the medium-pressure dynamic ring to overcome the medium-pressure elastic member and move, so that the first limit block moves out of the second arc groove along the first inclined surface, and the medium-pressure sealing ring is separated from the abutment with the static ring sealing ring; the other end of the high-pressure dynamic ring passes through the third arc groove and is provided with a second limit block, and the width dimension of the second limit block is between the width dimension of the third arc groove and the width dimension of the fourth arc groove. The rotation of the control disk can drive the high-pressure dynamic ring to overcome the high-pressure elastic member and move, so that the second limit block moves out of the fourth arc groove along the second inclined surface, and the high-pressure sealing ring is separated from the abutment with the static ring sealing ring.

[0008] Preferably, the first arc-shaped groove and the third arc-shaped groove are arranged along the same circumferential direction, and the arc length of the third arc-shaped groove is greater than the arc length of the first arc-shaped groove.

[0009] Preferably, the low-speed cross-medium rotary sealing device is also provided with a transmission ring and a rotary push rod; the transmission ring is arranged on the connecting seat and can perform axial reciprocating movement relative to the connecting seat; one end of the rotary push rod is hinged to the transmission ring, and the other end is hinged to the control disk.

[0010] Preferably, the low-speed cross-medium rotary sealing device is also provided with a pressure piston; the pressure piston is arranged on the fixed shell along the axial sliding of the connecting seat, one end is connected to the external medium, and the other end is provided with a pressure spring; the transmission ring is sleeved on the outside of the connecting seat, and the outer circumferential surface of the transmission ring is provided with a transmission groove along the circumferential direction, and a control pin is provided on the pressure piston, and the control pin extends into the transmission groove, and can slide relatively along the transmission groove and drive the transmission ring to move axially along the connecting seat.

[0011] Preferably, one end of the low-pressure dynamic ring, the medium-pressure dynamic ring and the high-pressure dynamic ring close to the static ring can all be connected to the external medium.

[0012] Preferably, the low-speed cross-medium rotary sealing device is further provided with an adjusting pin; the adjusting pin is arranged on the fixed shell and can push the pressure piston to overcome the pressure spring to move.

[0013] Preferably, the low-pressure dynamic ring, the medium-pressure dynamic ring and the high-pressure dynamic ring are coaxially arranged on the connecting seat with the main shaft.

[0014] Preferably, the low-pressure elastic member, the medium-pressure elastic member and the high-pressure elastic member all adopt a spiral spring structure.

[0015] Preferably, the numbers of springs used in the low-pressure elastic member, the medium-pressure elastic member and the high-pressure elastic member are different and gradually increase.

[0016] The low-speed cross-medium rotary sealing device of the present invention has the following beneficial technical effects:

[0017] 1. In the present invention, by providing a low-pressure dynamic ring, a medium-pressure dynamic ring and a high-pressure dynamic ring and low-pressure elastic parts, medium-pressure elastic parts and high-pressure elastic parts with different elastic forces, a gradually increasing sealing pressure can be formed when the low-pressure dynamic ring, the medium-pressure dynamic ring and the high-pressure dynamic ring abut against the static ring. In this way, at different underwater depths, dynamic rings with different sealing pressures can be selected to work with the help of a control panel, thereby forming an optimal sealing pressure, reducing torque consumption and extending the service life of the sealing ring.

[0018] 2. In the present invention, by setting a pressure piston and a control disk, the movement of the pressure piston is controlled by water pressure and a pressure spring, so that the control disk can be driven to rotate, so that at different working water depths, the control disk can control the corresponding moving ring to work, so that the present invention can automatically adjust the sealing pressure according to the working water depth, and the control is convenient.

[0019] 3. In the present invention, by setting an adjusting pin and a pressure piston, the movement of the pressure piston can be controlled by rotating the adjusting pin, and the control disk can be driven to rotate, so that the initial sealing pressure of the low-speed cross-medium rotary sealing device of the present invention can be adjusted, making the device more convenient to use and having a wider range of uses. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic cross-sectional structural diagram of the low-speed cross-medium rotary sealing device of this embodiment;

[0021] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure along the AA direction;

[0022] Figure 3 for Figure 1 Schematic diagram of the cross-sectional structure along the BB direction;

[0023] Figure 4 for Figure 1 Schematic diagram of the cross-sectional structure along the CC direction;

[0024] Figure 5 for Figure 1 Schematic diagram of the cross-sectional structure along the DD direction;

[0025] Figure 6 for Figure 1 The local enlarged schematic diagram of point I in the middle;

[0026] Figure 7 This is a three-dimensional view of the control panel in this embodiment. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0028] Combination Figures 1 to 7 As shown, the low-speed cross-medium rotary sealing device of this embodiment includes a fixed shell 1, a connecting seat 2, a stationary ring 3, a low-pressure dynamic ring 4, a medium-pressure dynamic ring 5, a high-pressure dynamic ring 6 and a control disk 7. Among them, the connecting seat 2 is located in the fixed shell 1, and is sleeved and connected with the main shaft 8 that passes through the fixed shell 1 with a gap to rotate synchronously. The stationary ring 3 is fixedly arranged in the fixed shell 1 and sleeved on the outside of the main shaft 8, wherein a stationary ring sealing ring 9 is provided at one end facing the connecting seat 2.

[0029] The low-pressure dynamic ring 4 is movably arranged on the connecting seat 2 along the axial direction of the main shaft 8 through the low-pressure elastic member 10. A low-pressure sealing ring 11 is arranged at one end of the low-pressure dynamic ring 4 facing the static ring 3, and the low-pressure elastic member 10 can drive the low-pressure dynamic ring 4 to move until the low-pressure sealing ring 11 abuts against the static ring sealing ring 9, that is, the low-pressure elastic member 10 can drive the low-pressure dynamic ring 4 along the axial direction of the main shaft 8. Figure 1 The right side direction shown is moved relative to the connecting seat 2 so that the low-pressure sealing ring 11 is in contact with the static ring sealing ring 9 .

[0030] The medium-pressure dynamic ring 5 is movably arranged on the connecting seat 2 along the axial direction of the main shaft 8 through the medium-pressure elastic member 12. A medium-pressure sealing ring 13 is arranged at one end of the medium-pressure dynamic ring 5 facing the static ring 3, and the medium-pressure elastic member 12 can drive the medium-pressure dynamic ring 5 to move until the medium-pressure sealing ring 13 abuts against the static ring sealing ring 9, that is, the medium-pressure elastic member 12 can drive the medium-pressure dynamic ring 5 along the axial direction of the main shaft 8. Figure 1 The right side direction shown is moved relative to the connecting seat 2 so that the medium-pressure sealing ring 13 and the static ring sealing ring 9 are in contact with each other.

[0031] The high-pressure dynamic ring 6 is movably arranged on the connecting seat 2 along the axial direction of the main shaft 8 through the high-pressure elastic member 14. A high-pressure sealing ring 15 is arranged at one end of the high-pressure dynamic ring 6 facing the static ring 3, and the high-pressure elastic member 14 can drive the high-pressure dynamic ring 6 to move until the high-pressure sealing ring 15 abuts against the static ring sealing ring 9, that is, the high-pressure elastic member 14 can drive the high-pressure dynamic ring 6 along the axial direction of the main shaft 8. Figure 1 The right side direction shown is moved relative to the connecting seat 2 so that the high-pressure sealing ring 15 is in contact with the static ring sealing ring 9.

[0032] The control disk 7 is connected to the medium-pressure dynamic ring 5 and the high-pressure dynamic ring 6, and can cooperate with the medium-pressure elastic part 12 and the high-pressure elastic part 14 to respectively control the movement of the medium-pressure dynamic ring 5 and the high-pressure dynamic ring 6 relative to the connecting seat 2, thereby changing the abutment relationship between the medium-pressure sealing ring 13 and the high-pressure sealing ring 15 and the static ring sealing ring 9, that is, controlling the medium-pressure sealing ring 13 to abut or separate from the static ring sealing ring 9 and controlling the high-pressure sealing ring 15 to abut or separate from the static ring sealing ring 9.

[0033] At the same time, the elastic forces between the low-pressure elastic member 10, the medium-pressure elastic member 12 and the high-pressure elastic member 14 are different in magnitude and increase successively, that is, the abutting forces generated when the three drive the corresponding dynamic rings to make the corresponding sealing rings abut against the static ring sealing ring 9 are different in magnitude, thereby forming sealing pressures of different magnitudes respectively.

[0034] In the low-speed cross-medium rotary sealing device of the present embodiment, by arranging low-pressure dynamic ring, medium-pressure dynamic ring and high-pressure dynamic ring and low-pressure elastic parts, medium-pressure elastic parts and high-pressure elastic parts with different elastic forces, a gradually increasing sealing pressure can be formed when the low-pressure dynamic ring, medium-pressure dynamic ring and high-pressure dynamic ring form abutment with the static ring. In this way, at different underwater depths, the dynamic ring that can form different sealing pressures can be selected with the help of the control panel to work, thereby forming the optimal sealing pressure, reducing torque consumption and extending the service life of the sealing ring.

[0035] Combination Figures 1 to 7As shown, in the low-speed cross-medium rotary sealing device of this embodiment, the control disk 7 is located at one end of the connecting seat 2 and is sleeved on the outer side of the main shaft 8 and can rotate relative to the connecting seat 2. The control disk 7 is provided with a first arc groove 16 and a second arc groove 17 connected in the circumferential direction, and a third arc groove 18 and a fourth arc groove 19 connected in the circumferential direction. Among them, the width of the second arc groove 17 is greater than the width of the first arc groove 16, and a first inclined surface 20 with an inclined transition in the depth direction is provided between the two. The width of the fourth arc groove 19 is greater than the width of the third arc groove 18, and a second inclined surface 21 with an inclined transition in the depth direction is provided between the two. The other end of the medium-pressure dynamic ring 5 passes through the first arc groove 16 and is provided with a first stopper 22, the width of which is between the width of the first arc groove 16 and the width of the second arc groove 17, and the rotation of the control disk 7 can drive the medium-pressure dynamic ring 5 to overcome the medium-pressure elastic member 12 to move, so that the first stopper 22 moves out of the second arc groove 17 along the first inclined surface 20, so that the medium-pressure sealing ring 13 is separated from the contact with the static ring sealing ring 9. The other end of the high-pressure dynamic ring 6 passes through the third arc groove 18 and is provided with a second stopper 23, the width of which is between the width of the third arc groove 18 and the width of the fourth arc groove 19, and the rotation of the control disk 7 can drive the high-pressure dynamic ring 6 to overcome the high-pressure elastic member 14 to move, so that the second stopper 23 moves out of the fourth arc groove 19 along the second inclined surface 21, so that the high-pressure sealing ring 15 is separated from the contact with the static ring sealing ring 9.

[0036] In this embodiment, by setting two-stage arc grooves with different widths on the control disk, and setting limit blocks at one end of the medium-pressure dynamic ring and the high-pressure dynamic ring passing through the corresponding arc grooves, respectively, by utilizing the size relationship between the limit blocks and the arc grooves, the positional relationship between the limit blocks and the arc grooves can be changed by rotating the control disk relative to the connecting seat, that is, overcoming the corresponding elastic part to exit the arc groove and make the corresponding sealing ring break away from the contact with the static ring sealing ring, or entering the arc groove under the action of the corresponding elastic part to make the corresponding sealing ring move to form abutment with the static ring sealing ring, thereby realizing the change of the sealing pressure.

[0037] Combination Figure 7 As shown, in this embodiment, the first arc groove 16 and the third arc groove 18 are arranged along the same circumferential direction, and as shown in FIG. Figure 7 As shown, the fourth arc groove 19 is located at the counterclockwise extension position of the third arc groove 18, and the second arc groove 17 is also located at the counterclockwise extension position of the first arc groove 16. At the same time, the arc length of the third arc groove 18 is greater than the arc length of the first arc groove 16.

[0038] In this way, when the control disk is driven to rotate in one direction, the medium-pressure sealing ring and the high-pressure sealing ring can be abutted against the static ring sealing ring in sequence, thereby increasing the sealing pressure in sequence. Of course, in other embodiments, the second arc groove and the fourth arc groove can be designed in reverse, and the medium-pressure sealing ring and the static ring sealing ring can be abutted against each other, and the high-pressure sealing ring and the static ring sealing ring can be abutted against each other by driving the control disk to rotate in different directions.

[0039] Combination Figures 1 to 7 As shown, in the low-speed cross-medium rotary sealing device of this embodiment, a transmission ring 24 and a rotary push rod 25 are also provided. The transmission ring 24 is arranged on the connecting seat 2, and can perform axial reciprocating movement relative to the connecting seat 2. The rotary push rod 25 is located between the transmission ring 24 and the control disk 7, and one end of the rotary push rod 25 is hinged to the transmission ring 24, and the other end is hinged to the control disk 7.

[0040] At this time, by controlling the axial reciprocating movement of the transmission ring relative to the connecting seat, the transmission ring can be pushed to rotate in a circumferential direction relative to the connecting seat with the help of a rotating push rod, thereby achieving control of the medium-pressure dynamic ring and the high-pressure dynamic ring.

[0041] Combination Figure 6 As shown, in this embodiment, by providing a flat key 26 and a corresponding flat key groove between the transmission ring 24 and the connecting seat 2, the flat key 26 is utilized to realize the linear reciprocating movement between the transmission ring 24 and the connecting seat 2.

[0042] Combination Figures 1 to 7 As shown, the low-speed cross-medium rotary sealing device is also provided with a pressure piston 27. The pressure piston 27 is slidably arranged on the fixed shell 1 along the axial direction of the connecting seat 2, one end of which is connected to the external medium, and the other end is provided with a pressure spring 28. At the same time, the transmission ring 24 is sleeved on the outer side of the connecting seat 2, and the outer circumferential surface of the transmission ring 24 is provided with a transmission groove 29 along the circumferential direction. The pressure piston 27 is provided with a control pin 30, and the control pin 30 extends into the transmission groove 29, and can slide relatively along the transmission groove 29 and drive the transmission ring 24 to move axially along the connecting seat 2.

[0043] At this time, when the medium pressure changes, that is, the medium pressure formed at different depths is different, the medium pressure can cooperate with the pressure spring to push the pressure piston to move back and forth, thereby driving the transmission ring to move axially relative to the connecting seat through the control pin, thereby realizing the rotation adjustment of the control disk, and achieving automatic adjustment control of the medium-pressure dynamic ring and the high-pressure dynamic ring as the depth changes.

[0044] Combination Figure 1 As shown, in this embodiment, the ends of the low-pressure dynamic ring 4, the medium-pressure dynamic ring 5 and the high-pressure dynamic ring 6 close to the static ring 3 can all be connected to the external medium. Figure 1As shown, the external medium can flow into the interior of the fixed shell 1 through the gap between the main shaft 8 and the fixed shell 1, thereby forming a pressure effect on the end of the low-pressure dynamic ring 4. The pressure formed by the external medium can push the low-pressure dynamic ring 4 to overcome the low-pressure elastic member 10 to Figure 1 When the medium pressure moves to the left, the external medium can flow to the end of the medium pressure dynamic ring 5. Similarly, when the pressure formed by the external medium pressure can push the medium pressure dynamic ring 5 to overcome the medium pressure elastic member 12, the medium pressure dynamic ring 5 will move to the left. Figure 1 When moving in the left direction, the external medium can flow to the end of the high-pressure dynamic ring 6. In this way, under the action of the pressure piston, the action of the dynamic ring can be controlled in conjunction with the pressure of the external medium, so that the dynamic rings can be automatically switched according to the depth change to form different sealing pressures.

[0045] Combination Figure 1 As shown, in the low-speed cross-medium rotary sealing device of this embodiment, an adjusting pin 31 is further provided. The adjusting pin 31 is arranged on the fixed shell 1, and can push the pressure piston 27 to overcome the pressure spring 28 to move. In this way, the initial position of the pressure piston can be changed by the adjusting pin, thereby changing the initial positions of the medium-pressure dynamic ring and the high-pressure dynamic ring, and forming different initial sealing pressures.

[0046] In addition, combined Figure 1 and Figure 6 As shown, a housing groove 32 is also provided on the fixed housing 1, and the control pin 30 passes through the housing groove 32 to form a connection with the transmission ring 24. By providing the housing groove, the reciprocating movement of the control pin can be guided, thereby improving the stability of the reciprocating movement of the pressure piston and the transmission ring.

[0047] Combination Figure 1 As shown, in this embodiment, the low-pressure dynamic ring 4, the medium-pressure dynamic ring 5 and the high-pressure dynamic ring 6 are all arranged on the connecting seat 2 in a coaxial manner with the main shaft 8. In this way, a uniform sealing pressure can be formed along the circumferential direction of the main shaft, thereby improving the sealing effect and the service life of the sealing ring.

[0048] Combination Figure 1 , Figure 3 and Figure 6 As shown, in this embodiment, the low-pressure elastic member 10, the medium-pressure elastic member 12 and the high-pressure elastic member 14 all adopt a spiral spring structure to form an axial force on the corresponding dynamic ring along the main shaft 8. Further, the low-pressure elastic member 10, the medium-pressure elastic member 12 and the high-pressure elastic member 14 adopt a composition form of different numbers of springs, thereby forming different elastic forces. For example, in this embodiment, the low-pressure elastic member 10 is composed of four spiral springs evenly distributed in the circumferential direction, the medium-pressure elastic member 12 is composed of six spiral springs evenly distributed in the circumferential direction, and the high-pressure elastic member 14 is composed of eight spiral springs evenly distributed in the circumferential direction.

[0049] In this embodiment, three moving rings are arranged on the connecting seat, namely, a low-pressure moving ring, a medium-pressure moving ring and a high-pressure moving ring, realizing three different sealing pressure settings, wherein the medium-pressure moving ring is not limited to a moving ring that forms one sealing pressure, and can be composed of moving rings that form multiple different sealing pressures. The sealing pressures formed by these different moving rings are between the sealing pressure formed by the low-pressure moving ring and the sealing pressure formed by the high-pressure moving ring, so they are collectively referred to as medium-pressure moving rings. Arranging multiple medium-pressure moving rings with different sealing pressures, such as a first medium-pressure moving ring, a second medium-pressure moving ring, a third medium-pressure moving ring, etc., can reduce the sealing pressure difference between adjacent moving rings, increase the number of sealing pressure divisions, and further improve the control accuracy and effect.

[0050] Combination Figures 1 to 7 As shown, the working process of the low-speed cross-medium rotary sealing device of this embodiment is as follows:

[0051] When the low-speed cross-medium rotary sealing device of this embodiment needs to be used in a hydraulic motor, first, the fixed shell 1 is fixedly connected to the housing of the hydraulic motor, and the main shaft 8 of the hydraulic motor passes through the fixed shell 1, and the connecting seat 2 is fixedly connected to the main shaft 8, for example, by a pin.

[0052] When the water pressure at the location of the hydraulic motor is low, the force of the water pressure on the pressure piston 27 is less than the force of the pressure spring 28 on the pressure piston 27, and the pressure piston 27 is in the state of Figure 1 The control pin 30 drives the control disk 7 to the initial position through the transmission ring 24 and the rotating push rod 25, that is, Figure 1 In the position shown, the force of water pressure on the low-pressure dynamic ring 4 is less than the force of the low-pressure elastic member 10 on the low-pressure dynamic ring 4. Under the action of the low-pressure elastic member 10, the low-pressure dynamic ring 4 moves to the low-pressure sealing ring 11 and keeps in contact with the static ring sealing ring 9, while the medium-pressure dynamic ring 5 and the high-pressure dynamic ring 6 both keep away from the static ring 3. Specifically, the first limit block 22 on the medium-pressure dynamic ring 5 is located at the first arc groove 16, and the second limit block 23 on the high-pressure dynamic ring 6 is located at the third arc groove 18. At this time, when the main shaft 8 starts to rotate, the connecting seat 2 rotates with the low-pressure dynamic ring 4, driving the low-pressure sealing ring 11 to rotate, and a liquid film is generated between the low-pressure sealing ring 11 and the static ring sealing ring 9 to achieve sealing. At the same time, the transmission ring 24 rotates synchronously with the connecting seat 2 through the flat key 26, and then rotates synchronously with the control disk 7 through the rotating push rod 25, so that the control disk 7, the transmission ring 24 and the connecting seat 2 are in a relatively static relationship, and the control pin 30 slides relatively in the transmission groove 29. At this time, the hydraulic motor works under a smaller sealing pressure.

[0053] When the hydraulic motor descends and the water pressure gradually increases, the force of the external water on the end of the pressure piston 27 through the channel 33 on the fixed shell 1 increases, thereby pushing the pressure piston 27 to overcome the force of the pressure spring 28. Figure 1 The pressure piston 27 drives the transmission ring 24 relative to the connecting seat 2 through the control pin 30. Figure 1 The medium-pressure dynamic ring 5 moves in the left direction as shown, thereby pushing the control disk 7 to start rotating relative to the connecting seat 2 by rotating the push rod 25, so that the medium-pressure dynamic ring 5 moves along the first arc groove 16, and the high-pressure dynamic ring 6 moves along the third arc groove 18. As the hydraulic motor descends, the water pressure of the external water continues to increase and pushes the pressure piston 27 to continue to move, so that the control disk 7 continues to rotate. When the first limit block 22 moves to the first inclined surface 20, the medium-pressure elastic member 12 begins to push the medium-pressure dynamic ring 5 to move in the direction close to the static ring 3, and the first limit block 22 slides into the second arc groove 17. When the hydraulic motor descends to a certain depth, the first limit block 22 enters the second arc groove 17, and the medium-pressure sealing ring 13 moves to abut against the static ring sealing ring 9. At the same time, the water pressure pushes the low-pressure dynamic ring 4 to overcome the low-pressure elastic member 10 to Figure 1 The movement in the left direction as shown separates the low-pressure sealing ring 11 from the static ring sealing ring 9, thereby automatically switching from the low-pressure dynamic ring 4 to the medium-pressure dynamic ring 5 for operation. Since the number of threaded springs of the medium-pressure elastic part 12 is greater than the number of threaded springs of the low-pressure elastic part 10, the hydraulic motor operates under a higher sealing pressure.

[0054] As the hydraulic motor continues to descend and the water pressure further increases, the force of the water pressure on the end of the pressure piston 27 continues to push the pressure piston 27 to overcome the pressure spring 28. Figure 1 The pressure piston 27 moves in the left direction as shown, and the pressure piston 27 continues to drive the transmission ring 24 relative to the connecting seat 2 through the control pin 30. Figure 1 The hydraulic motor moves in the left direction as shown, thereby continuing to push the control disk 7 to rotate relative to the connecting seat 2 by rotating the push rod 25, so that the first limit block 22 moves relatively in the second arc groove 17, and the second limit block 23 moves relatively along the third arc groove 18 in the direction close to the fourth arc groove 19. The hydraulic motor continues to descend, and the water pressure continues to increase to push the pressure piston 27 to continue to move, so that the control disk 7 continues to rotate. When the second limit block 23 moves to the second inclined surface 21, the high-pressure elastic member 14 begins to push the high-pressure dynamic ring 6 to move in the direction close to the static ring 3, and the second limit block 23 slides in the fourth arc groove 19. When the hydraulic motor descends to a certain depth, the second limit block 23 enters the fourth arc groove 19, and the high-pressure sealing ring 15 moves to abut against the static ring sealing ring 9. At the same time, the water pressure pushes the medium-pressure dynamic ring 5 to overcome the medium-pressure elastic member 12 to Figure 1The movement in the left direction as shown separates the medium-pressure sealing ring 13 from the static ring sealing ring 9, thereby automatically switching from the medium-pressure dynamic ring 5 to the high-pressure dynamic ring 6 for operation. Since the number of threaded springs of the high-pressure elastic part 14 is greater than that of the medium-pressure elastic part 12, the hydraulic motor operates under the highest sealing pressure.

[0055] As the hydraulic motor rises and the water pressure decreases, the force of the water pressure on the pressure piston 27 decreases, and the pressure spring 28 starts to push the pressure piston 27 to Figure 1 The transmission ring 24 moves in the right direction as shown, and the control pin 30 drives the transmission ring 24 to move relative to the connecting seat 2 Figure 1 As shown, the connecting seat 2 pushes the control disk 7 to rotate in the opposite direction by rotating the push rod 25, so that the first limit block 22 moves relatively along the second arc groove 17, and the second limit block 23 moves relatively along the fourth arc groove 19. As the hydraulic motor rises, the water pressure decreases, and the force of the water pressure on the medium-pressure dynamic ring 5 decreases. Under the action of the medium-pressure elastic member 12, the medium-pressure dynamic ring 5 begins to move toward the direction close to the static ring 3, so that the medium-pressure sealing ring 13 and the static ring sealing ring 9 are abutted again. At the same time, the control disk 7 rotates in the opposite direction, and the second limit block 23 overcomes the high-pressure elastic member 14 through the second inclined surface 21, and drives the high-pressure dynamic ring 6 to move away from the static ring 3, so that the second limit block 23 moves to the third arc groove 18, and the high-pressure sealing ring 15 is separated from the static ring sealing ring 9, so that the high-pressure dynamic ring 6 automatically switches to the medium-pressure dynamic ring 5 to work, so that the hydraulic motor works under a higher sealing pressure.

[0056] As the hydraulic motor continues to rise and the water pressure continues to drop, the pressure spring 28 continues to push the pressure piston 27 to Figure 1 The transmission ring 24 moves in the right direction as shown, and the control pin 30 continues to drive the transmission ring 24 relative to the connecting seat 2 Figure 1 The connecting seat 2 continues to push the control disk 7 to rotate in the opposite direction by rotating the push rod 25, so that the second limit block 23 moves relatively along the third arc groove 18, and the first limit block 22 moves relatively along the second arc groove 17. As the hydraulic motor continues to rise and the water pressure continues to decrease, the force of the water pressure on the low-pressure dynamic ring 4 decreases, and the low-pressure dynamic ring 4 begins to move toward the direction close to the static ring 3 under the action of the low-pressure elastic member 10, so that the low-pressure sealing ring 11 and the static ring sealing ring 9 are abutted again. At the same time, the reverse rotation of the control disk 7 causes the first limit block 22 to overcome the medium-pressure elastic member 12 through the first inclined surface 20 and drive the medium-pressure dynamic ring 5 to move away from the static ring 3, so that the first limit block 22 moves to the first arc groove 16, and the medium-pressure sealing ring 13 is separated from the static ring sealing ring 9, so that the medium-pressure dynamic ring 5 automatically switches to the low-pressure dynamic ring 4 to work, so that the hydraulic motor works under the minimum sealing pressure.

[0057] When it is necessary to adjust the initial sealing pressure of the low-speed cross-medium rotary sealing device of this embodiment, the adjusting pin 31 is rotated, and under the action of the pressure spring 28, the position of the pressure piston 27 is changed, thereby driving the control disk 7 to rotate, so that as described above, the hydraulic motor works under different sealing pressures to complete the adjustment of the initial sealing pressure.

Claims

1. A low-speed cross-medium rotary sealing device, characterized in that: It comprises a fixed shell, a connecting seat, a static ring, a low-pressure dynamic ring, a medium-pressure dynamic ring, a high-pressure dynamic ring and a control disk; the connecting seat is located in the fixed shell, and is connected with a main shaft sleeve that maintains a gap and passes through the fixed shell for synchronous rotation; the static ring is fixedly arranged in the fixed shell, and a static ring sealing ring is provided at one end facing the connecting seat; the low-pressure dynamic ring is movably arranged on the connecting seat along the axial direction of the main shaft through a low-pressure elastic member, and a low-pressure sealing ring is provided at one end of the low-pressure dynamic ring facing the static ring, and the low-pressure elastic member can drive the low-pressure dynamic ring to move until the low-pressure sealing ring abuts against the static ring sealing ring; the medium-pressure dynamic ring is movably arranged on the connecting seat along the axial direction of the main shaft through a medium-pressure elastic member, and a medium-pressure sealing ring is provided at one end of the medium-pressure dynamic ring facing the static ring. The pressure elastic member can drive the medium-pressure dynamic ring to move until the medium-pressure sealing ring abuts against the static ring sealing ring; the high-pressure dynamic ring is movably arranged on the connecting seat along the axial direction of the main shaft through the high-pressure elastic member, and a high-pressure sealing ring is provided at one end of the high-pressure dynamic ring facing the static ring, and the high-pressure elastic member can drive the high-pressure dynamic ring to move until the high-pressure sealing ring abuts against the static ring sealing ring; the control disk is connected to the medium-pressure dynamic ring and the high-pressure dynamic ring, and can cooperate with the medium-pressure elastic member and the high-pressure elastic member to respectively control the movement of the medium-pressure dynamic ring and the high-pressure dynamic ring relative to the connecting seat, and change the abutting relationship between the medium-pressure sealing ring and the high-pressure sealing ring and the static ring sealing ring; the elastic forces of the low-pressure elastic member, the medium-pressure elastic member and the high-pressure elastic member are different; The control disk can rotate relative to the connecting seat, and is provided with a first arc groove and a second arc groove connected in a circumferential direction, and a third arc groove and a fourth arc groove connected in a circumferential direction; the width of the second arc groove is greater than the width of the first arc groove, and a first inclined surface with an inclined transition in a depth direction is provided between the two; the width of the fourth arc groove is greater than the width of the third arc groove, and a second inclined surface with an inclined transition in a depth direction is provided between the two; the other end of the middle pressure dynamic ring passes through the first arc groove and is provided with a first limit block, and the width dimension of the first limit block is between the width dimension of the first arc groove and the width dimension of the second arc groove The rotation of the control disk can drive the medium-pressure dynamic ring to overcome the medium-pressure elastic part and move, so that the first limit block moves out of the second arc groove along the first inclined surface, and the medium-pressure sealing ring is separated from the abutment with the static ring sealing ring; the other end of the high-pressure dynamic ring passes through the third arc groove and is provided with a second limit block, and the width dimension of the second limit block is between the width dimension of the third arc groove and the width dimension of the fourth arc groove. The rotation of the control disk can drive the high-pressure dynamic ring to overcome the high-pressure elastic part and move, so that the second limit block moves out of the fourth arc groove along the second inclined surface, and the high-pressure sealing ring is separated from the abutment with the static ring sealing ring.

2. The low-speed cross-medium rotary sealing device according to claim 1, characterized in that: The first arc-shaped groove and the third arc-shaped groove are arranged along the same circumferential direction, and the arc length of the third arc-shaped groove is greater than the arc length of the first arc-shaped groove.

3. The low-speed cross-medium rotary sealing device according to claim 1, characterized in that: The low-speed cross-medium rotary sealing device is also provided with a transmission ring and a rotary push rod; the transmission ring is arranged on the connecting seat and can perform axial reciprocating movement relative to the connecting seat; one end of the rotary push rod is hinged to the transmission ring, and the other end is hinged to the control disk.

4. The low-speed cross-medium rotary sealing device according to claim 3, characterized in that: The low-speed cross-medium rotary sealing device is also provided with a pressure piston; the pressure piston is arranged on the fixed shell along the axial sliding of the connecting seat, one end of which is connected to the external medium, and the other end is provided with a pressure spring; the transmission ring is sleeved on the outside of the connecting seat, and the outer circumferential surface of the transmission ring is provided with a transmission groove along the circumferential direction, and a control pin is provided on the pressure piston, and the control pin extends into the transmission groove, can slide relatively along the transmission groove and drive the transmission ring to move axially along the connecting seat.

5. The low-speed cross-medium rotary sealing device according to claim 4, characterized in that: One end of the low-pressure dynamic ring, the medium-pressure dynamic ring and the high-pressure dynamic ring close to the static ring can be communicated with the external medium.

6. The low-speed cross-medium rotary sealing device according to claim 4, characterized in that: The low-speed cross-medium rotary sealing device is also provided with an adjusting pin; the adjusting pin is arranged on the fixed shell and can push the pressure piston to overcome the pressure spring to move.

7. The low-speed cross-medium rotary sealing device according to any one of claims 1 to 6, characterized in that: The low-pressure dynamic ring, the medium-pressure dynamic ring and the high-pressure dynamic ring are coaxially arranged on the connecting seat with the main shaft.

8. The low-speed cross-medium rotary sealing device according to any one of claims 1 to 6, characterized in that: The low-pressure elastic member, the medium-pressure elastic member and the high-pressure elastic member all adopt a spiral spring structure.

9. The low-speed cross-medium rotary sealing device according to claim 8, characterized in that: The low-pressure elastic member, the medium-pressure elastic member and the high-pressure elastic member use different numbers of springs that increase gradually.

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