A reducer shaft end dynamic sealing device with pressure self-adaptive compensation

Abstract

This invention relates to the field of shaft sealing technology, specifically to a dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation. It includes a housing containing a rotating shaft, a sealing sleeve rotatably mounted on the housing, a sealing conical surface on the inner side of the sealing sleeve, a sealing groove inside the sealing sleeve, a compensation pressure frame with a sealing conical ring rotatably connected to the sealing conical surface, an annular expansion bladder fixedly mounted on the front end face of the sealing conical ring and connected to the sealing groove, an oil-filling chamber inside the annular expansion bladder, a centrifugal rotating ring rotatably connected to the housing, and four centrifugal cylinders fixedly mounted on the rotating shaft. The beneficial effects of this invention are: through the coordinated design of the centrifugal rotating ring, centrifugal cylinders, and centrifugal piston, the rotational speed of the rotating shaft is converted into a pressure signal in the pressure chamber in real time, and transmitted to the pressure guiding chamber of the compensation cylinder via a pipe, driving the compensation piston to produce an axial displacement proportional to the rotational speed.

Description

Technical Field

[0001] This invention relates to the field of shaft sealing technology, specifically to a dynamic sealing device for the shaft end of a speed reducer with pressure adaptive compensation. Background Technology

[0002] As a power transmission device, speed reducers are widely used in various industrial scenarios and new energy vehicle fields. In electric vehicle drive systems, speed reducers are one of the core components of the electric drive assembly, and their shaft end sealing performance directly determines the reliability, transmission efficiency, service life, and maintenance costs of the motor and reducer. Especially under high-speed, high-torque, and frequent start-stop conditions, the problem of lubricating oil leakage caused by seal failure is particularly prominent, which not only contaminates the inside of the motor but may also cause serious faults such as motor insulation failure.

[0003] In the prior art, there are various shaft end sealing solutions for speed reducers. For example, patent document CN110486455B discloses a speed reducer sealing structure, which improves the sealing environment and prevents seal failure caused by sludge accumulation by setting a stationary ring cover, a rotating ring cover, and a mechanical end face sealing assembly installed between the two, and adding a coal dust prevention sealing assembly on the rotating ring cover. However, the above technical solutions still have the following technical problems in use: Existing sealing structures (such as the combination of mechanical end face sealing components and dustproof packing in the prior art) are essentially static preset seals. The contact pressure between the sealing surfaces is set during equipment installation and lacks an active adjustment mechanism during operation. In the actual operation of the reducer, the shaft speed, load, temperature, and internal lubricating oil pressure are constantly and dynamically changing. These changes can cause thermal expansion, wear, or creep of the sealing elements, resulting in dynamic changes in the gap between the sealing surfaces. Existing technology cannot actively adjust the clamping force of the sealing surfaces based on these real-time operating parameters. As a result, at high speeds, high pressures, or drastic temperature changes, the sealing surfaces may wear more rapidly due to overload, or leak due to insufficient pressure after wear of the sealing surfaces at low speeds and low pressures, thus affecting the reliability and durability of the electric vehicle drive system.

[0004] Based on this, the present invention provides a dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation to solve the problems mentioned in the background art. Summary of the Invention

[0005] This invention addresses the technical problems existing in the prior art by providing a dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation. This solves the problem that existing sealing structures lack the ability to adaptively compensate for pressure changes in the sealing interface, leading to a sharp decline in sealing performance under varying operating conditions.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation, comprising a housing, in which a rotating shaft is rotatably mounted, and further comprising: A sealing rubber tube is rotatably sleeved on the machine housing. The inner side of the sealing rubber tube is provided with a sealing cone surface, and a sealing groove is opened inside the sealing rubber tube. The compensating pressure frame has a sealing cone ring rotatably connected to the sealing cone surface. The front end face of the sealing cone ring is fixed with an annular expansion bladder connected to the sealing groove. An oil filling chamber is opened inside the annular expansion bladder. A centrifugal ring is rotatably connected to the casing. Four centrifugal cylinders are fixedly mounted on the rotating shaft. The top of each centrifugal cylinder is fixedly connected to the centrifugal ring. A centrifugal piston is slidably connected inside the centrifugal cylinder. A first spring is installed on the bottom surface of the centrifugal piston. The other end of the first spring is fixedly connected to the inner bottom of the centrifugal cylinder. A pressure transformer is provided on the centrifugal cylinder and at a position corresponding to the top of the centrifugal piston. Two compensating cylinders are fixedly mounted on the housing. A compensating piston is slidably connected inside the compensating cylinder. A pressure guiding chamber and an outer oil chamber are respectively provided on both sides of the compensating cylinder and the compensating piston. The pressure guiding chamber is connected to the transformer chamber, and the outer oil chamber is connected to the oil filling chamber. An elastic traction component is installed between the compensating piston and the compensating pressure frame. A radial locking unit is configured to apply a radial locking force to the sealing sleeve in response to the axial displacement of the compensating pressure frame; The lubricating oil chamber is located inside the housing. A spiral blade is fixed on the rotating shaft at the position corresponding to the lubricating oil chamber and a pressure piston is slidably connected thereto. A second spring is fixed between the pressure piston and the housing.

[0007] Based on the above technical solution, the present invention can be further improved as follows.

[0008] Preferably, the sealing sleeve, sealing cone ring, and annular expansion bladder are all made of rubber, and the axis of the centrifugal cylinder is perpendicular to the axis of the rotating shaft.

[0009] Preferably, two through pipes are fixedly mounted on the housing, and a first annular chamber communicating with the transformer chamber is provided between the centrifugal rotating ring and the housing. The tail ends of the two through pipes are connected to the first annular chamber, and the other ends of the two through pipes are respectively connected to the pressure guiding chambers on the two compensating oil cylinders. Oil pipes are connected to the two outer oil chambers. A second annular chamber is opened in the compensating pressure frame, and the other ends of the two oil pipes are connected to the second annular chamber. The oil filling chamber is rotatably connected to the second annular chamber.

[0010] Preferably, a one-way air supply valve and a first pressure gauge are installed on both of the through pipes, a one-way oil supply valve is installed on the lubricating oil chamber and the two outer oil chambers, and a second pressure gauge is installed on the second annular chamber.

[0011] Preferably, the radial locking unit includes two symmetrically arranged clamping frames. Each clamping frame is hinged to two connecting rods with the compensating pressure frame. Two screws are movably installed between the two clamping frames. Each screw has two locking nuts threaded onto it. Each clamping frame has a mounting hole that mates with the screw. The clamping frame has two clamping strips. The inner wall of each clamping strip is embedded with universal ball bearings. The outer circumferential surface of the sealing rubber cylinder has two limiting ring grooves that mate with the clamping strips.

[0012] Preferably, the elastic traction assembly includes a pull rod fixed on the compensating piston, the compensating cylinder and the compensating pressure frame are both slidably connected to the pull rod, a limit nut is threaded on the pull rod, and a pressure-reducing spring is sleeved on the pull rod at a position corresponding to the limit nut and the compensating pressure frame.

[0013] Preferably, the centrifugal piston is made of cast iron, and a first sealing ring is installed on the outer periphery of the centrifugal piston, the compensating piston and the pressure piston. A plurality of second sealing rings connected to the rotating shaft are installed on the inner wall of the housing.

[0014] Preferably, the cone angle of the sealing cone surface is 15°-25°.

[0015] Preferably, the spiral blade is made of engineering plastic, and the outer diameter of the spiral blade is 0.5 to 0.7 times the inner diameter of the lubricating oil chamber.

[0016] The beneficial effects of this invention are: 1. This invention, through the coordinated design of a centrifugal rotating ring, centrifugal cylinder, and centrifugal piston, converts the rotational speed of the shaft into a real-time air pressure signal in the pressure chamber. This signal is then transmitted to the pressure guiding chamber of the compensating cylinder via a connecting pipe, driving the compensating piston to generate an axial displacement proportional to the rotational speed. This displacement, on the one hand, flexibly pushes the compensating pressure frame and sealing cone ring through an elastic traction component, causing the sealing cone ring and the sealing cone surface of the sealing rubber sleeve to form a basic clamping force that dynamically increases with the rotational speed. On the other hand, it simultaneously compresses the hydraulic oil in the outer oil chamber, injecting it into the filling chamber of the annular expansion bladder through an oil pipe. This causes the annular expansion bladder to expand and tightly adhere to the sealing groove, achieving a secondary strengthening of the contact pressure on the sealing surface. The aforementioned multi-stage linkage mechanism of centrifugal, air pressure, hydraulic, and mechanical components enables the sealing clamping force to be dynamically adjusted according to the real-time changes in shaft speed, load, and internal oil pressure. This solves the problem that existing static preset seals cannot adapt to dynamic working conditions. It avoids overload wear of the sealing surface under high speed, high pressure, or drastic temperature changes, and automatically compensates for insufficient pressure after wear of the sealing surface under low speed, low pressure, or when the sealing surface is worn. This significantly improves the sealing reliability and equipment service life under varying working conditions.

[0017] 2. In this invention, when the compensating pressure frame moves axially, the radial locking unit drives the clamp frame to move radially closer via a linkage. The universal ball bearings on the clamping bar are embedded in the limiting ring groove of the sealing rubber tube, applying a uniform radial preload force to effectively suppress the expansion and deformation of the sealing rubber tube under high pressure. At the same time, the universal ball bearings allow relative rotation to avoid friction and wear, forming a synergistic effect of axial compensation and radial auxiliary sealing. The pressure-reducing spring in the elastic traction component can automatically extend after the sealing surface wears, maintaining the initial contact pressure. The limiting nut precisely limits the maximum compression to achieve overload protection. The spiral blades in the lubricating oil chamber rotate with the shaft to agitate the oil, driving the pressure piston to compress the second spring to form a hydraulic pressure difference, which helps to improve the tightness between the sealing cone ring and the sealing rubber tube. The above-mentioned centrifugal drive main sealing pressure compensation, radial auxiliary sealing of the radial locking unit, wear adaptive compensation of the spring mechanism, and pressure difference generated by the spiral blades to assist in tightness are organically linked to form a new dynamic adaptive sealing system that is different from the existing static seal or single mechanical end face seal. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a dynamic sealing device for the shaft end of a speed reducer with pressure adaptive compensation according to the present invention. Figure 2 For the present invention Figure 1 A schematic diagram of the cross-sectional structure; Figure 3 For the present invention Figure 2 A magnified schematic diagram of the local structure at point A; Figure 4 For the present invention Figure 2 A magnified schematic diagram of the local structure at point B; Figure 5 This is a schematic diagram of the structure of the compensating pressure frame and sealing cone ring of the present invention; Figure 6 For the present invention Figure 5 A structural diagram from another angle; Figure 7 This is a schematic diagram of the structure of the clamp frame of the present invention; Figure 8 This is a schematic diagram of the structure of the sealing rubber tube of the present invention; Figure 9 This is a schematic diagram of the centrifugal rotating ring and centrifugal cylinder of the present invention; Figure 10 This is a schematic diagram of the centrifugal piston and the first spring of the present invention.

[0019] The attached diagram lists the components represented by each number as follows: 1. Housing; 2. Shaft; 3. Sealing sleeve; 4. Compensating pressure frame; 5. One-way oil replenishing valve; 6. Compensating oil cylinder; 7. Clamping frame; 101. Lubricating oil chamber; 102. Spiral blade; 103. Pressure piston; 104. Second spring; 201. Centrifugal rotating ring; 202. Centrifugal cylinder; 203. Centrifugal piston; 204. First spring; 205. Transformer chamber; 206. Connecting pipe; 207. One-way air replenishing valve; 208. First pressure gauge; 301. Sealing groove; 302. Limiting ring groove; 401. Sealing cone ring; 402. Annular expansion bladder; 403. Oil filling chamber; 404. Second pressure gauge; 601. Compensating piston; 602. Pressure guiding chamber; 603. External oil chamber; 604. Oil pipe; 605. Tie rod; 606. Limiting nut; 607. Compensating spring; 701. Connecting rod; 702. Screw; 703. Locking nut; 704. Clamping bar; 705. Universal ball bearing. Detailed Implementation

[0020] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0021] The present invention provides the following preferred embodiments. like Figure 1-10 As shown, a dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation includes a housing 1, in which a rotating shaft 2 is rotatably mounted. Multiple second sealing rings connected to the rotating shaft 2 are installed on the inner wall of the housing 1. The device also includes: The sealing tube 3 is rotatably sleeved on the housing 1. The inner side of the sealing tube 3 is provided with a sealing cone surface, and a sealing groove 301 is provided inside the sealing tube 3 at the position corresponding to the sealing cone surface. In this embodiment, the cone angle of the sealing cone surface is 15°-25°, preferably 20°; The compensating pressure frame 4 has a sealing cone ring 401 rotatably connected to the sealing cone surface. The front end face of the sealing cone ring 401 is fixedly fitted with an annular expansion bladder 402 connected to the sealing groove 301. An oil filling cavity 403 is opened in the annular expansion bladder 402. The sealing rubber sleeve 3, the sealing cone ring 401, and the annular expansion bladder 402 are all made of rubber. In this embodiment, the rubber material is preferably made of hydrogenated nitrile rubber. The hydrogenated nitrile rubber material design of the sealing sleeve 3, the sealing cone ring 401 and the annular expansion bladder 402 allows the sealing cone ring 401 to undergo elastic deformation under the push of the compensating pressure frame 4, thereby forming a tighter fit with the sealing cone surface of the sealing sleeve 3. Even if there is a slight radial runout or axial movement of the rotating shaft 2, the elasticity of the rubber can automatically compensate for the gap and ensure the reliability of the seal. The shape of the annular expansion bladder 402 matches the sealing groove 301, and when it is not filled with oil, there is a small gap between it and the wall of the sealing groove 301. When hydraulic oil is injected into the filling chamber 403, the annular expansion bladder 402 expands radially, and its outer wall surface tightly fits the bottom and side wall of the sealing groove 301 to form a dynamic sealing interface. The axis of the centrifugal cylinder 202 is arranged perpendicular to the axis of the rotating shaft 2, so that the direction of the centrifugal force on the centrifugal piston 203 when the rotating shaft 2 rotates is completely consistent with the axis of the centrifugal cylinder 202, thereby efficiently converting the centrifugal force into the linear motion of the piston, avoiding the loss of component force, and improving the sensitivity of speed and pressure conversion. A centrifugal ring 201 is rotatably connected to the housing 1. Four centrifugal cylinders 202 are arrayed on the rotating shaft 2. The axis of the centrifugal cylinders 202 is perpendicular to the axis of the rotating shaft 2. The top of each centrifugal cylinder 202 is fixedly connected to the centrifugal ring 201. A centrifugal piston 203 is slidably connected inside the centrifugal cylinder 202. A first spring 204 is installed on the bottom surface of the centrifugal piston 203. The other end of the first spring 204 is fixedly connected to the inner bottom of the centrifugal cylinder 202. A pressure chamber 205 is provided on the centrifugal cylinder 202 and at a position corresponding to the centrifugal piston 203. The centrifugal piston 203 is made of cast iron. When the shaft 2 rotates, the centrifugal piston 203 is subjected to centrifugal force and moves. After the centrifugal piston 203 moves, it compresses the gas in the pressure transformer chamber 205. The centrifugal piston 203 is made of cast iron, which has high density and concentrated mass. When the rotating shaft 2 rotates, it can generate a large centrifugal force, thereby significantly compressing the gas in the pressure chamber 205. The rotation of the shaft 2 drives the centrifugal cylinder 202 to rotate synchronously. Under the action of centrifugal force, the centrifugal piston 203 slides outward along the radial direction of the guide tube, compressing the gas in the pressure transformer chamber 205, so that the gas pressure increases proportionally with the rotation speed. The pressure is transmitted through the pipe 206 to the pressure chamber 602 of the compensating cylinder 6, thereby driving the compensating piston 601; This structure achieves dynamic linkage between the sealing drive pressure and the rotation speed of the shaft 2, without the need for external energy. Furthermore, the cast iron piston has good wear resistance, a low coefficient of thermal expansion, and stable pressure response during long-term operation. Two compensating cylinders 6 are fixedly mounted on the housing 1. A compensating piston 601 is slidably connected inside the compensating cylinder 6. A pressure guiding chamber 602 and an outer oil chamber 603 are respectively provided on both sides of the compensating cylinder 6 and the compensating piston 601. The pressure guiding chamber 602 is connected to the transformer chamber 205, and the outer oil chamber 603 is connected to the oil filling chamber 403. An elastic traction component is installed between the compensating piston 601 and the compensating pressure frame 4. In this embodiment, two through pipes 206 are fixedly mounted on the housing 1. A first annular chamber communicating with the transformer chamber 205 is provided between the centrifugal rotating ring 201 and the housing 1. The tail ends of the two through pipes 206 are connected to the first annular chamber. The other ends of the two through pipes 206 are respectively connected to the pressure guiding chambers 602 on the two compensating oil cylinders 6. A one-way air supply valve 207 and a first pressure gauge 208 are installed on the two through pipes 206. Two outer oil chambers 603 are connected to oil pipes 604. A second annular chamber is opened in the compensation pressure frame 4. The other ends of the two oil pipes 604 are connected to the second annular chamber. The oil filling chamber 403 is rotatably connected to the second annular chamber. A second pressure gauge 404 is installed on the second annular chamber; After the air pressure in the transformer chamber 205 increases, it enters the pressure guiding chamber 602 through the through pipe 206, pushing the compensation piston 601 to move to one side. After the compensation piston 601 moves, it can further compensate for the tightness of the connection and sealing strength between the sealing cone ring 401 and the sealing rubber sleeve 3. On the other hand, it compresses the hydraulic oil in the outer oil chamber 603 and enters the filling chamber 403 of the annular expansion bladder 402 through the oil pipe 604 and the second ring chamber. After the annular expansion bladder 402 expands, it tightly adheres to the sealing groove 301. One-way gas supply valve 207 allows gas to be supplied to transformer chamber 205 after initial installation or long-term operation to maintain the reference pressure and avoid lack of sealing force at low speed due to gas leakage; The first pressure gauge 208 is used to monitor the pressure in transformer chamber 205 in real time. The second pressure gauge 404 on the second annular chamber directly reflects the oil pressure entering the annular expansion bladder 402, thereby indirectly indicating the sealing surface clamping force.

[0022] The elastic traction assembly includes a pull rod 605 fixedly mounted on the compensation piston 601, a compensation cylinder 6 and a compensation pressure frame 4 that are slidably connected to the pull rod 605, a limit nut 606 threadedly installed on the pull rod 605, and a pressure spring 607 sleeved on the pull rod 605 at the position corresponding to the limit nut 606 and the compensation pressure frame 4. When the compensating piston 601 applies a pulling force to the compensating pressure frame 4 through the pull rod 605, the compensating spring 607 is compressed first, which flexibly transmits the force to the compensating pressure frame 4, avoiding rigid impact. When the gap between the sealing surface increases due to wear, the pressure spring 607 automatically extends, pushing the compensation pressure frame 4 forward to maintain the initial contact pressure between the sealing cone ring 401 and the sealing cone surface. The limit nut 606 can precisely set the maximum compression of the spring, thereby limiting the maximum sealing pressure; This structure combines buffering, wear compensation, and overload protection, extending the service life of the sealing system and making it particularly suitable for the long-life, maintenance-free requirements of electric vehicle gearboxes. A radial locking unit is configured to apply a radial locking force to the sealing sleeve 3 in response to the axial displacement of the compensating pressure frame 4; The radial locking unit includes two symmetrically arranged clamping frames 7. Each clamping frame 7 is hinged to two connecting rods 701. Two screws 702 are movably installed between the two clamping frames 7. Each screw 702 is threaded with two locking nuts 703. Each clamping frame 7 has a mounting hole that mates with the screw 702. The clamping frame 7 is provided with two clamping strips 704. The inner wall of each clamping strip 704 is embedded with universal ball bearings 705. The outer circumferential surface of the sealing rubber cylinder 3 is provided with two limiting ring grooves 302 that mate with the clamping strips 704. The radial locking unit converts the axial displacement of the compensating pressure frame 4 into the radial clamping force of the clamp frame 7 on the sealing rubber sleeve 3 through two symmetrical clamping frames 7, connecting rod 701, screw 702 and locking nut 703. When the compensating pressure frame 4 moves toward the sealing cylinder 3 due to the sealing pressure, the connecting rod 701 pushes the two clamping frames 7 to move closer to each other along the screw 702, and the universal ball bearings 705 on the clamping bar 704 press into the limiting ring groove 302 of the sealing cylinder 3, applying a uniform radial preload to the sealing cylinder 3 to prevent it from expanding and deforming under high pressure. Meanwhile, the universal ball bearing 705 allows relative rotation between the sealing sleeve 3 and the clamp 7, avoiding friction and wear; This structure achieves the linkage between axial compensation and radial auxiliary sealing, improving the deformation resistance and overall sealing limit of the sealing sleeve 3. A lubricating oil chamber 101 is opened inside the housing 1. A spiral blade 102 is fixedly installed on the rotating shaft 2 at the position corresponding to the lubricating oil chamber 101 and a pressure piston 103 is slidably connected thereto. A second spring 104 is fixedly installed between the pressure piston 103 and the housing 1.

[0023] One-way oil replenishment valves 5 are installed on the lubricating oil chamber 101 and the two outer oil chambers 603; The one-way oil replenishing valve 5 is installed on the lubricating oil chamber 101 and the outer oil chamber 603. It can automatically replenish oil when the system is short of oil, ensuring that the oil is full and preventing cavitation. The centrifugal piston 203, the compensating piston 601 and the pressure piston 103 are all equipped with a first sealing ring on their outer periphery; The spiral blade 102 is made of engineering plastic, and the outer diameter of the spiral blade 102 is 0.5 to 0.7 times the inner diameter of the lubricating oil chamber 101, preferably 0.6 times. When the shaft 2 rotates, the spiral blade 102 agitates the lubricating oil, causing the pressure piston 103 to be subjected to an axial force pointing towards the second spring 104. After the second spring 104 is compressed, the oil pressure in the lubricating oil chamber 101 decreases, thereby reducing the internal pressure of the lubricating oil chamber 101 and increasing the pressure difference between the inside and outside of the sealing cone ring 401, which in turn helps to improve the tightness of the sealing cone ring 401 towards the inside of the sealing rubber sleeve 3.

[0024] The specific steps for using this invention are as follows: During the preparation phase, after the device assembly is completed, gas is supplied to the transformer chamber 205 and the first annular chamber through the one-way gas supply valve 207 on the through pipe 206, and the reference pressure is calibrated with the help of the first pressure gauge 208. Hydraulic oil is supplied through the one-way oil supply valve 5 of the lubricating oil chamber 101 and the outer oil chamber 603 to ensure that the chamber is full of oil. The screw 702 and the locking nut 703 of the radial locking unit are adjusted to make the clamp 7 complete the initial positioning. At the same time, the limit nut 606 of the elastic traction component is turned to set the preload of the pressure replenishing spring 607, thus completing the preliminary preparation for the adjustment of the sealing reference parameters and the replenishment of the medium. The first spring 204 is in a pre-compressed state when the shaft 2 is stationary, providing the initial restoring force for the centrifugal piston 203; The second spring 104 is in a free state when the shaft 2 is stationary, or it is compressed when the pressure piston 103 is pushed by the oil. During operation, the rotating shaft 2 drives the centrifugal ring 201 to rotate synchronously. The four centrifugal cylinders 202 perpendicular to the axis of the rotating shaft 2 rotate with the rotating shaft 2. The cast iron centrifugal piston 203 overcomes the elastic force of the first spring 204 and slides radially outward under the action of centrifugal force, compressing the gas in the pressure transformer chamber 205 so that its pressure increases with the increase of rotation speed. The pressurized gas is transported to the pressure guide chamber 602 of the compensation cylinder 6 through the first ring chamber and the through pipe 206, pushing the compensation piston 601 to move axially. On the one hand, the compensation piston 601 flexibly drives the compensation pressure frame 4 to move towards the sealing cylinder 3 through the tie rod 605 and the pressure compensation spring 607, so that the sealing cone ring 401 is tightly attached to the sealing cone surface of the sealing cylinder 3 to form a basic dynamic seal. On the other hand, it squeezes the hydraulic oil in the outer oil chamber 603. The hydraulic oil is injected into the filling chamber 403 of the annular expansion bladder 402 through the oil pipe 604 and the second ring chamber, so that the annular expansion bladder 402 expands and tightly attaches to the sealing groove 301 to further enhance the sealing effect. Meanwhile, the axial displacement of the compensation pressure frame 4 is linked to the radial locking unit through the connecting rod 701, which drives the two clamp frames 7 to move radially closer along the screw 702. The universal ball bearings 705 on the clamping bar 704 are embedded in the limiting ring groove 302 of the sealing rubber tube 3, and a uniform radial preload is applied to suppress the high pressure deformation of the sealing rubber tube 3. The universal ball bearings 705 can adapt to the relative rotation of the sealing rubber tube 3 to avoid wear. When the rotating shaft 2 rotates, the spiral blades 102 on its surface agitate the oil in the lubricating oil chamber 101, which drives the pressure piston 103 to compress the second spring 104 to form a hydraulic pressure difference, which helps to improve the tightness between the sealing cone ring 401 and the sealing rubber tube 3. The higher the speed, the stronger the centrifugal pressure boosting effect. The sealing compensation force is adaptively and dynamically improved. The pressure spring 607 can automatically compensate for the gap caused by the wear of the sealing surface. The limiting nut 606 limits the maximum compression of the spring to achieve overload protection. The first and second sealing rings throughout the process ensure that each chamber is tightly sealed, and the first pressure gauge 208 and the second pressure gauge 404 monitor the air pressure and oil pressure parameters in real time. In the final stage, after the rotating shaft 2 stops rotating, the centrifugal force disappears, the centrifugal piston 203 moves back under the reset action of the first spring 204, the pressure in the pressure transformer chamber 205 and the pressure guide chamber 602 gradually depressurizes, the compensation piston 601 resets in the reverse direction, driving the pull rod 605 and the pressure replenishing spring 607 to unload, the compensation pressure frame 4 retracts synchronously, the hydraulic oil in the annular expansion bladder 402 flows back to the outer oil chamber 603, causing the annular expansion bladder 402 to contract and reset, the radial locking unit releases the radial clamping force on the sealing rubber sleeve 3 in conjunction with the connecting rod 701, the pressure piston 103 returns to the initial position under the reset action of the second spring 104, the pressure difference in the lubricating oil chamber 101 is eliminated, the sealing contact parts are released from the clamping state, all moving components are reset to the initial standby position, completing the shutdown and depressurization and the overall reset of the device.

[0025] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation, comprising a housing (1) in which a rotating shaft (2) is rotatably mounted, characterized in that, Also includes: A sealing tube (3) is rotatably mounted on the housing (1). The inner side of the sealing tube (3) is provided with a sealing cone surface, and a sealing groove (301) is provided inside the sealing tube (3). The compensating pressure frame (4) is rotatably connected to a sealing cone ring (401) connected to a sealing cone surface. The front end face of the sealing cone ring (401) is fixedly fitted with an annular expansion bladder (402) connected to a sealing groove (301). An oil filling chamber (403) is opened inside the annular expansion bladder (402). A centrifugal ring (201) is rotatably connected to the casing (1). Four centrifugal cylinders (202) are fixedly mounted on the rotating shaft (2). The top of each centrifugal cylinder (202) is fixedly connected to the centrifugal ring (201). A centrifugal piston (203) is slidably connected inside the centrifugal cylinder (202). A first spring (204) is installed on the bottom surface of the centrifugal piston (203). The other end of the first spring (204) is fixedly connected to the bottom of the centrifugal cylinder (202). A pressure chamber (205) is provided on the centrifugal cylinder (202) and at the position corresponding to the centrifugal piston (203). Two compensating cylinders (6) are fixedly mounted on the housing (1). A compensating piston (601) is slidably connected inside the compensating cylinder (6). A pressure guiding chamber (602) and an outer oil chamber (603) are respectively provided on both sides of the compensating cylinder (6) and the compensating piston (601). The pressure guiding chamber (602) is connected to the transformer chamber (205), and the outer oil chamber (603) is connected to the oil filling chamber (403). An elastic traction component is installed between the compensating piston (601) and the compensating pressure frame (4). The radial locking unit is configured to apply a radial locking force to the sealing sleeve (3) in response to the axial displacement of the compensating pressure frame (4); The lubricating oil chamber (101) is located inside the housing (1). A spiral blade (102) is fixed on the rotating shaft (2) at the position corresponding to the lubricating oil chamber (101) and a pressure piston (103) is slidably connected. A second spring (104) is fixed between the pressure piston (103) and the housing (1).

2. The dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, The sealing rubber cylinder (3), sealing cone ring (401) and annular expansion bladder (402) are all made of rubber, and the axis of the centrifugal cylinder (202) is perpendicular to the axis of the rotating shaft (2).

3. The dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, Two through pipes (206) are fixedly mounted on the housing (1). A first annular chamber communicating with the transformer chamber (205) is provided between the centrifugal rotating ring (201) and the housing (1). The tail ends of the two through pipes (206) are connected to the first annular chamber. The other ends of the two through pipes (206) are respectively connected to the pressure guiding chambers (602) on the two compensating oil cylinders (6). Oil pipes (604) are connected to the two outer oil chambers (603). A second annular chamber is opened in the compensating pressure frame (4). The other ends of the two oil pipes (604) are connected to the second annular chamber. The oil filling chamber (403) is rotatably connected to the second annular chamber.

4. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, One-way air supply valve (207) and first pressure gauge (208) are installed on both of the two through pipes (206). One-way oil supply valve (5) is installed on the lubricating oil chamber (101) and the two outer oil chambers (603). Second pressure gauge (404) is installed on the second ring chamber.

5. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, The radial locking unit includes two symmetrically arranged clamping frames (7). Each clamping frame (7) is hinged to two connecting rods (701) and the compensating pressure frame (4). Two screws (702) are movably installed between the two clamping frames (7). Each screw (702) is threaded with two locking nuts (703). Each clamping frame (7) has a mounting hole that mates with the screw (702). The clamping frame (7) has two clamping strips (704). The inner wall of each clamping strip (704) is embedded with universal ball bearings (705). The outer circumferential surface of the sealing rubber cylinder (3) has two limiting ring grooves (302) that mate with the clamping strips (704).

6. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, The elastic traction assembly includes a pull rod (605) fixed on the compensation piston (601). The compensation cylinder (6) and the compensation pressure frame (4) are slidably connected to the pull rod (605). A limit nut (606) is threaded on the pull rod (605). A pressure spring (607) is sleeved on the pull rod (605) at the position corresponding to the limit nut (606) and the compensation pressure frame (4).

7. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, The centrifugal piston (203) is made of cast iron. The centrifugal piston (203), the compensation piston (601) and the pressure piston (103) are all equipped with a first sealing ring on their outer periphery. The inner wall of the housing (1) is equipped with a plurality of second sealing rings connected to the rotating shaft (2).

8. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, The cone angle of the sealing cone surface is 15°-25°.

9. A dynamic sealing device for the shaft end of a reducer with pressure adaptive compensation according to claim 1, characterized in that, The spiral blade (102) is made of engineering plastic, and the outer diameter of the spiral blade (102) is 0.5 to 0.7 times the inner diameter of the lubricating oil chamber (101).

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