Sealing device for the output shaft of a rolling mill reduction gear

Abstract

The utility model relates to the technical field of speed reducer, concretely relates to a sealing device for rolling mill speed reducer output shaft. The utility model provides a sealing device for rolling mill speed reducer output shaft, the rolling mill bearing sealing device is sleeved on the shaft body of vertical arrangement, the rolling mill bearing sealing device includes dynamic ring, static ring and lubricating oil automatic circulation mechanism, the dynamic ring is lower than static ring, and the oil groove is formed between the dynamic ring and static ring, the lubricating oil automatic circulation mechanism includes automatic oil suction and discharge mechanism and backflow mechanism, the automatic oil suction and discharge mechanism includes the oil discharge channel and suction and discharge oil structure who arranges on static ring, the oil discharge channel includes inlet and outlet oil chamber and oil discharge chamber, the inlet and outlet oil chamber includes first vertical chamber, horizontal chamber and second vertical chamber. Lubricating oil automatic circulation mechanism does not need external power, and relies on self structure design to complete oil discharge work, and the oil discharge effect is good.

Description

Technical Field

[0001] This utility model relates to the field of speed reducer technology, specifically to a sealing device for the output shaft of a rolling mill speed reducer. Background Technology

[0002] In large rolling mill reducers, if the reducer is horizontally installed but the output shaft is at the bottom and vertical (i.e., the output shaft is perpendicular to the ground), the mechanical seal structure of the output shaft (including the stationary and rotating rings) must resist the tendency of lubricating oil to leak downwards due to gravity. In particular, under high-temperature conditions, the viscosity of the lubricating oil decreases, increasing its fluidity and making it easier to flow along the output shaft under gravity and penetrate into the sealing gap between the rotating and stationary rings. At high speeds, the centrifugal force generated by the rotation of the output shaft makes it easier for the lubricating oil to be thrown into the sealing gap between the rotating and stationary rings, thus disrupting the oil film balance on the sealing surface and increasing the possibility of lubricating oil entering the sealing gap.

[0003] During normal operation of the rolling mill reducer, lubricating oil forms a film on the output shaft surface, serving both lubrication and sealing purposes. However, because the output shaft is vertically downward, the lubricating oil tends to flow downward under gravity. This tendency is more pronounced when the equipment is operating at high temperatures or high speeds. Initially, the lubricating oil flows downward along the circumference of the output shaft and gradually accumulates in the oil groove between the rotating and stationary rings. As lubricating oil continues to flow into the oil groove, the oil pressure gradually increases. When the oil pressure exceeds the limit that the sealing structure can withstand, the lubricating oil begins to permeate outward through the tiny gap between the rotating and stationary rings. Once the lubricating oil begins to permeate, the oil film balance on the sealing surface is disrupted, and the leakage gradually increases. The leaked lubricating oil continues to flow downward under gravity, forming obvious oil stains. Utility Model Content

[0004] (I) The problem to be solved by this utility model is that when the output shaft of the reducer is perpendicular to the ground, the mechanical seal structure of the output shaft is prone to lubricating oil leakage.

[0005] (II) Technical Solution

[0006] A sealing device for the output shaft of a rolling mill reducer, wherein the rolling mill bearing sealing device is sleeved on a vertically arranged shaft, and the rolling mill bearing sealing device includes a rotating ring, a stationary ring, and an automatic lubricating oil circulation mechanism; the rotating ring is lower than the stationary ring, and an oil groove is formed between the rotating ring and the stationary ring;

[0007] The automatic lubricating oil circulation mechanism includes an automatic oil suction and discharge mechanism and a return mechanism. The automatic oil suction and discharge mechanism includes an oil discharge channel provided on the stationary ring and an oil suction and discharge structure. The oil discharge channel includes an oil inlet and discharge chamber and an oil discharge chamber. The oil inlet and discharge chamber includes a first vertical chamber, a horizontal chamber and a second vertical chamber.

[0008] The first vertical cavity and the second vertical cavity are vertically disposed on the stationary ring. The two ends of the horizontal cavity are respectively connected to the top ends of the first vertical cavity and the second vertical cavity. The ends of the first vertical cavity and the second vertical cavity away from the horizontal cavity are connected to the oil groove. One end of the oil discharge cavity is connected to the horizontal cavity, and the other end is connected to the return mechanism. The end of the return mechanism away from the oil discharge cavity is connected to the bearing chamber.

[0009] The oil suction and discharge structure includes a third spring, an oil discharge ball core, a first piston structure, a second piston structure, and multiple stepped protrusions; the first piston structure and the second piston structure are respectively installed in the first vertical cavity and the second vertical cavity, the third spring is vertically installed in the oil discharge cavity, the oil discharge ball core is fixed to the bottom end of the third spring, and the stepped protrusions are provided on the inner bottom wall of the oil tank;

[0010] The first piston structure and the second piston structure cooperate with the stepped protrusion to change the pressure in the oil inlet and outlet chambers; when the mill bearing sealing device is in the oil suction state, the oil in the oil groove flows into the oil inlet and outlet chamber from the oil inlet of the first piston structure; when the mill bearing sealing device is in the oil discharge state, under the action of pressure, the oil in the oil inlet and outlet chamber pushes open the oil discharge ball core and enters the oil discharge chamber and flows back to the bearing chamber through the return mechanism.

[0011] According to one embodiment of the present invention, the bottom surface of the stationary ring has an annular protrusion coaxial with it, the top of the moving ring is provided with an annular groove, the annular protrusion extends into the annular groove, and the first vertical cavity, the horizontal cavity and the second vertical cavity are disposed in the annular protrusion; the oil discharge cavity includes a connected flow channel cavity and an oil outlet cavity, the flow channel cavity is vertically disposed on the stationary ring, the bottom end of the flow channel cavity is connected to the horizontal cavity, one end of the oil outlet cavity is connected to the top end of the flow channel cavity, and the other end is connected to the return mechanism, the top end of the third spring is fixed to the inner wall of the flow channel cavity, and the oil discharge ball core acts on the connection between the flow channel cavity and the horizontal cavity and is used to control the opening and closing of the connection.

[0012] According to one embodiment of the present invention, the first piston structure includes a first spring and an oil inlet piston. The top end of the first spring is fixed to the inner top wall of the first vertical cavity, the length of the first spring is less than the length of the first vertical cavity, the oil inlet piston is fixed to the bottom end of the first spring, and the oil inlet piston is provided with an oil inlet hole.

[0013] According to one embodiment of the present invention, the second piston structure includes a second spring and a movable piston. The top end of the second spring is fixed to the inner top wall of the second vertical cavity, and the movable piston is fixed to the bottom end of the second spring. The length of the second spring is less than the length of the second vertical cavity.

[0014] According to one embodiment of the present invention, the step protrusion is in the shape of an isosceles trapezoid, comprising a first inclined surface, a top surface, and a second inclined surface connected in sequence; the direction from the first inclined surface to the second inclined surface is the length direction of the step protrusion, and the width direction of the step protrusion is the same as the radial direction of the moving ring.

[0015] According to one embodiment of the present invention, when the first piston structure and the second piston structure are respectively misaligned with the stepped protrusion, under the action of the first spring, the top end of the oil inlet piston is located in the first vertical cavity, and its bottom end acts on the inner bottom wall of the annular groove, and the oil inlet hole on the oil inlet piston extends out of the first vertical cavity; under the action of the second spring, the top end of the moving piston is located in the second vertical cavity, and its bottom end acts on the inner bottom wall of the annular groove.

[0016] According to one embodiment of the present invention, the sum of the length of the first spring in its natural state and the length of the oil inlet piston is greater than the distance between the top surface of the stepped protrusion and the inner top wall of the first vertical cavity; the sum of the length of the second spring in its natural state and the length of the moving piston is greater than the distance between the top surface of the stepped protrusion and the inner top wall of the second vertical cavity.

[0017] According to one embodiment of the present invention, a plurality of the stepped protrusions are uniformly arranged around the axis of the moving ring.

[0018] According to one embodiment of the present invention, the reflux mechanism includes a reflux pipe, one end of which is connected to the end of the oil outlet chamber away from the flow channel chamber, and the other end of which is connected to the bearing chamber.

[0019] According to one embodiment of the present invention, the bottom opening of the flow channel cavity and the transverse cavity are connected by a cylindrical cavity, the diameter of the oil discharge ball core is larger than the diameter of the cylindrical cavity, and the diameter of the oil discharge ball core is smaller than the diameter of the flow channel cavity.

[0020] The beneficial effects of this invention are as follows: The automatic lubricating oil circulation mechanism in this embodiment requires no external power and completes the oil discharge work through its own structural design, achieving good oil discharge efficiency. Each discharge is 1-2 ml, and a small amount of oil is always present in the oil tank, providing a certain sealing effect and preventing the intrusion of external dust and water. The discharged lubricating oil can flow back to the bearing chamber of the reducer through the return pipe. Even with continuous operation of the output shaft, there is no need to add lubricating oil separately, achieving recycling. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A schematic diagram of a sealing device for the output shaft of a rolling mill reducer provided in an embodiment of this utility model;

[0023] Figure 2 A top view of a sealing device for the output shaft of a rolling mill reducer provided in an embodiment of this utility model;

[0024] Figure 3 Provided for the embodiments of this utility model Figure 2 Sectional view of AA;

[0025] Figure 4 Provided for the embodiments of this utility model Figure 2 Sectional view of BB;

[0026] Figure 5 This is a top view of the sealing device for the output shaft of a rolling mill reducer provided in this embodiment of the present invention after removing the oil suction and discharge structure;

[0027] Figure 6 Provided for the embodiments of this utility model Figure 5 Sectional view of CC;

[0028] Figure 7 A schematic diagram of the first state of the sealing device for the output shaft of the rolling mill reducer provided in this embodiment of the utility model;

[0029] Figure 8 A schematic diagram of the second state of the sealing device for the output shaft of a rolling mill reducer provided in an embodiment of this utility model;

[0030] Figure 9 A schematic diagram of the third state of the sealing device for the output shaft of the rolling mill reducer provided in this embodiment of the utility model;

[0031] Figure 10 A schematic diagram of the fourth state of the sealing device for the output shaft of the rolling mill reducer provided in this embodiment of the utility model;

[0032] Figure 11 A schematic diagram of the fifth state of the sealing device for the output shaft of a rolling mill reducer provided in an embodiment of this utility model;

[0033] Figure 12 A schematic diagram of the sixth state of the sealing device for the output shaft of the rolling mill reducer provided in this embodiment of the utility model.

[0034] Icons: 1. Shaft; 2. Bearing; 3. Moving ring; 301. Annular groove; 4. Stationary ring; 401. Oil drain channel; 402. Temperature measurement channel; 403. Purge channel; 404. Pressure measurement channel; 405. Annular protrusion; 406. First vertical cavity; 407. Horizontal cavity; 408. Second vertical cavity; 409. Flow channel cavity; 410. Oil outlet cavity; 5. Labyrinth channel; 6. Micro-protrusion structure; 7. Skeleton oil seal; 8. Sealing ring; 9. Oil suction and discharge structure; 10. Oil drain connector; 11. Compressed air purging nozzle; 12. First spring; 13. Oil inlet piston; 14. Second spring; 15. Moving piston; 16. Third spring; 17. Oil drain ball core; 18. Stepped protrusion; 181. First inclined surface; 182. Top surface; 183. Second inclined surface. Detailed Implementation

[0035] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0036] like Figures 1-12 As shown, one embodiment of this utility model provides a sealing device for the output shaft of a rolling mill reducer. The rolling mill bearing sealing device is sleeved on a vertically arranged shaft 1. The rolling mill bearing sealing device includes a moving ring 3, a stationary ring 4, and an automatic lubricating oil circulation mechanism. The moving ring 3 is lower than the stationary ring 4, and an oil groove is formed between the moving ring 3 and the stationary ring 4.

[0037] The automatic lubricating oil circulation mechanism includes an automatic oil suction and discharge mechanism and a return mechanism. The automatic oil suction and discharge mechanism includes an oil discharge channel 401 provided on the stationary ring 4 and an oil suction and discharge structure 9. The oil discharge channel 401 includes an oil inlet and discharge chamber and an oil discharge chamber. The oil inlet and discharge chamber includes a first vertical chamber 406, a horizontal chamber 407 and a second vertical chamber 408.

[0038] The first vertical cavity 406 and the second vertical cavity 408 are vertically arranged on the stationary ring 4. The two ends of the horizontal cavity 407 are respectively connected to the top ends of the first vertical cavity 406 and the second vertical cavity 408. The ends of the first vertical cavity 406 and the second vertical cavity 408 away from the horizontal cavity 407 are connected to the oil groove. One end of the oil discharge cavity is connected to the horizontal cavity 407, and the other end is connected to the return mechanism. The end of the return mechanism away from the oil discharge cavity is connected to the bearing chamber.

[0039] The oil suction and discharge structure 9 includes a third spring 16, an oil discharge ball core 17, a first piston structure, a second piston structure, and multiple stepped protrusions 18; the first piston structure and the second piston structure are respectively installed in the first vertical cavity 406 and the second vertical cavity 408, the third spring 16 is vertically installed in the oil discharge cavity, the oil discharge ball core 17 is fixed to the bottom end of the third spring 16, and the stepped protrusions 18 are provided on the inner bottom wall of the oil tank;

[0040] The first piston structure and the second piston structure cooperate with the stepped protrusion 18 to change the pressure in the oil inlet and outlet chambers. When the mill bearing sealing device is in the oil suction state, the oil in the oil groove flows into the oil inlet and outlet chamber from the oil inlet of the first piston structure. When the mill bearing sealing device is in the oil discharge state, under the action of pressure, the oil in the oil inlet and outlet chamber pushes open the oil discharge ball core 17 and enters the oil discharge chamber and flows back to the bearing chamber through the return mechanism.

[0041] It should be noted that in large rolling mill reducers, when the output shaft is installed vertically downwards, the fundamental cause of leakage in the mechanical seal at its bottom (combination of dynamic ring 3 and stationary ring 4) lies in the combined effect of the continuous downward flow of lubricating oil under gravity and the disruption of the dynamic balance of the sealing end face. Specific factors include:

[0042] Gravity drive: Shaft 1 is vertically downward. Under the action of gravity, the lubricating oil naturally tends to flow downward along the surface of shaft 1. The sealing gap of the mechanical seal structure is located below bearing 2, which becomes a natural collection point for the downward flow of lubricating oil.

[0043] Reduced lubricating oil viscosity: Under high-temperature conditions, the operating environment of the rolling mill is hot, and the internal operating temperature of the reducer is also high. This high temperature significantly reduces the viscosity of the lubricating oil (thinning it), increasing its fluidity and making it easier to flow along the output shaft and penetrate into the sealing gap between the rotating ring 3 and the stationary ring 4. High-speed operation also causes a temporary decrease in lubricating oil viscosity (shear thinning), making it easier to flow. Furthermore, low-viscosity lubricating oil can more easily penetrate tiny gaps and capillary channels.

[0044] Changes in the state of the sealing end face: The mechanical seal relies on maintaining a very thin lubricating film between the end faces of the rotating ring 3 and the stationary ring 4 to achieve sealing (preventing dry friction) and reduce leakage. Ideally, this film is dynamically stable. However, when installed at the bottom with the shaft 1 facing downwards: gravity continuously "pulls" the lubricating oil towards the sealing end face. As the lubricating oil continuously flows into the sealing gap, the oil pressure within the sealing gap gradually increases. When the oil pressure exceeds the limit that the sealing structure can withstand, the lubricating oil begins to permeate outwards through the tiny gap between the rotating ring 3 and the stationary ring 4.

[0045] In contrast, in this embodiment, as Figure 1 As shown, a sealing gap (hereinafter referred to as an oil groove) is formed between the rotating ring 3 and the stationary ring 4. The lower surface of the stationary ring 4 has an annular protrusion 405 coaxially arranged therewith, and the stationary ring 4 has an annular groove 301. The gap formed between the inner wall of the annular groove 301 and the annular protrusion 405 constitutes part of the oil groove. The height of the annular protrusion 405 is less than the depth of the annular groove 301. When the rotating ring 3 and the stationary ring 4 are assembled together, the annular protrusion 405 on the stationary ring 4 extends into the annular groove 301 of the rotating ring 3, and the bottom surface of the annular protrusion 405 is higher than the inner bottom wall of the annular groove 301.

[0046] like Figure 3 , Figure 4 and Figure 6 As shown, the oil drain channel 401 includes an oil inlet / outlet chamber and an oil drain chamber. The oil inlet / outlet chamber includes a first vertical chamber 406, a horizontal chamber 407, and a second vertical chamber 408. The first vertical chamber 406 and the second vertical chamber 408 are vertically arranged in the annular protrusion 405 of the stationary ring 4, and the bottom openings of the first vertical chamber 406 and the second vertical chamber 408 are connected to the oil groove. The lengths of the first vertical chamber 406 and the second vertical chamber 408 are the same. The two ends of the horizontal chamber 407 are connected to the top ends of the first vertical chamber 406 and the second vertical chamber 408, respectively.

[0047] Furthermore, such as Figure 6 As shown, the oil discharge chamber includes a connected flow channel cavity 409 and an oil outlet cavity 410. The flow channel cavity 409 is vertically mounted on the stationary ring 4, and is higher than the transverse cavity 407. The cross-section of the flow channel cavity 409 is circular. The bottom opening of the flow channel cavity 409 is connected to the transverse cavity 407 via a cylindrical cavity. This cylindrical cavity and the flow channel cavity 409 are coaxially arranged, and the diameter of the cylindrical cavity is smaller than the diameter of the flow channel cavity 409. One end of the oil outlet cavity 410 is connected to the top end of the flow channel cavity 409, and the other end extends to the outer circumferential surface of the stationary ring 4. One end of the aforementioned return mechanism is connected to the opening formed on the outer circumferential surface of the oil outlet cavity 410 on the stationary ring 4, and the other end is connected to the bearing chamber of the reducer.

[0048] like Figure 4As shown, the oil drain ball 17 acts on the top opening of the cylindrical cavity. The third spring 16 is vertically arranged inside the flow channel cavity 409, with its bottom end connected to the oil drain ball 17 and its top end fixed to the inner wall of the flow channel cavity 409. It should be noted that the diameter of the oil drain ball 17 is larger than the diameter of the cylindrical cavity so as to block the cylindrical cavity; the diameter of the oil drain ball 17 is smaller than the diameter of the flow channel cavity 409 so that the oil drain ball 17 can move along the flow channel cavity 409 under the pull of the third spring 16.

[0049] In this embodiment, as Figure 4 As shown, the first piston structure includes a first spring 12 and an oil inlet piston 13. The top end of the first spring 12 is fixed to the inner top wall of the first vertical cavity 406, and the length of the first spring 12 is less than the length of the first vertical cavity 406. The oil inlet piston 13 is fixed to the bottom end of the first spring 12 and has an oil inlet hole. The second piston structure includes a second spring 14 and a movable piston 15. The top end of the second spring 14 is fixed to the inner top wall of the second vertical cavity 408, and the movable piston 15 is fixed to the bottom end of the second spring 14. It should be noted that the first vertical cavity 406 and the second vertical cavity 408 have the same length, the first spring 12 and the second spring 14 have the same specifications, and the oil inlet piston 13 and the movable piston 15 have the same length.

[0050] Furthermore, multiple stepped protrusions 18 are evenly provided on the inner bottom wall of the annular groove 301 of the moving ring 3 around the axis of the moving ring 3. The stepped protrusions 18 are in the shape of an isosceles trapezoid, such as... Figure 10 As shown, it includes a first inclined surface 181, a top surface 182, and a second inclined surface 183 connected in sequence. It is particularly important to note that... Figure 2 This is a top view of the sealing device for the output shaft of the rolling mill reducer. Figure 4 for Figure 2 Sectional view of BB, from Figure 4 It can be seen that the cross section of the step protrusion 18 is an isosceles trapezoid along the radial direction of the moving ring 3. In other words, the direction from the first inclined plane 181 to the second inclined plane 183 is the length direction of the step protrusion 18, and the width direction of the step protrusion 18 is the same as the radial direction of the moving ring 3.

[0051] In this embodiment, as Figure 7As shown, the sum of the length of the first spring 12 in its natural state and the length of the oil inlet piston 13 is greater than the distance between the top surface 182 of the stepped protrusion 18 and the inner top wall of the first vertical cavity 406; the sum of the length of the second spring 14 in its natural state and the length of the moving piston 15 is greater than the distance between the top surface 182 of the stepped protrusion 18 and the inner top wall of the second vertical cavity 408. Therefore, when the stepped protrusion 18 is offset from the two pistons, the oil inlet piston 13 and the moving piston 15 abut against the inner bottom wall of the annular groove 301 under the action of the first spring 12 and the second spring 14, respectively. At this time, the first spring 12 and the second spring 14 are at their maximum length.

[0052] The following details the oil suction and discharge process of the sealing device for the output shaft of the mill reducer:

[0053] The initial state of the oil absorption process is as follows: Figure 10 As shown, at this time, the first spring 12 and the second spring 14 are compressed, and the oil inlet piston 13 and the moving piston 15 act simultaneously on the top surface 182 of the first step protrusion 18, and the oil inlet hole of the oil inlet piston 13 extends into the first vertical cavity 406. Since the cylindrical cavity between the flow channel cavity 409 and the horizontal cavity 407 is blocked by the oil discharge ball core 17, and the oil inlet hole of the oil inlet piston 13 extends into the first vertical cavity 406, and the second vertical cavity 408 is blocked by the moving piston 15, a sealed cavity is formed between the first vertical cavity 406, the horizontal cavity 407 and the second vertical cavity 408, and the pressure in the cavity is stable.

[0054] As the shaft 1 drives the moving ring 3 to rotate in the first direction, the stepped protrusion 18 further rotates to... Figure 11 At the position shown, the oil inlet piston 13 acts on the second inclined surface 183 of the first step protrusion 18 and moves along the second inclined surface 183. During this process, the first spring 12 gradually extends, the height of the oil inlet piston 13 gradually decreases, the portion of the oil inlet piston 13 extending into the first vertical cavity 406 gradually decreases, and the oil inlet hole on the oil inlet piston 13 gradually opens. Therefore, the volume of the sealed cavity formed between the first vertical cavity 406, the horizontal cavity 407, and the second vertical cavity 408 increases, and the pressure in the sealed cavity decreases, forming a negative pressure. Under the action of the negative pressure, the lubricating oil in the gap between the lower surface of the annular protrusion 405 and the inner bottom wall of the annular groove 301 is drawn into the oil inlet hole of the oil inlet piston 13 and flows from the oil inlet hole into the sealed cavity between the first vertical cavity 406, the horizontal cavity 407, and the second vertical cavity 408.

[0055] As the shaft 1 continues to drive the rotating ring 3 in the first direction to rotate, the oil inlet piston 13 leaves the second inclined surface 183 of the stepped protrusion 18, thus acting on the inner bottom wall of the annular groove 301. Meanwhile, the moving piston 15 leaves the top surface 182 of the stepped protrusion 18 and moves downward along the second inclined surface 183 of the stepped protrusion 18 until the moving piston 15 leaves the second inclined surface 183 of the stepped protrusion 18 and acts on the inner bottom wall of the annular groove 301. During this process, because the volume of the sealed cavity formed between the first vertical cavity 406, the horizontal cavity 407, and the second vertical cavity 408 is constantly increasing, the lubricating oil in the oil groove is continuously drawn into the sealed cavity.

[0056] The above process is the oil absorption process.

[0057] When the inlet piston 13 and the moving piston 15 act simultaneously on the inner bottom wall of the annular groove 301, the desired effect is achieved. Figure 7 In the state shown, the volume of the sealed cavity formed between the first vertical cavity 406, the horizontal cavity 407 and the second vertical cavity 408 remains unchanged, and the oil inlet and outlet chambers are connected to the oil groove through the oil inlet hole on the oil inlet piston 13. Therefore, the pressure inside and outside the oil inlet and outlet chambers is in a balanced state.

[0058] Oil removal process according to Figure 8 , Figure 9 and Figure 10 The sequence is as follows: As the shaft 1 continues to drive the rotating ring 3 to rotate in the first direction, the oil inlet piston 13 acts on the first inclined surface 181 of the next stepped protrusion 18. The portion of the oil inlet piston 13 extending into the first vertical cavity 406 gradually increases, and the oil inlet hole on the oil inlet piston 13 gradually closes until the oil inlet piston 13 leaves the first inclined surface 181 of the stepped protrusion 18 and acts on the top surface 182 of the stepped protrusion 18. At this time, the oil inlet hole in the oil inlet piston 13 is completely extended into the first vertical cavity 406, and the first vertical cavity 406 is completely blocked. At this time, the sealed cavity formed between the first vertical cavity 406, the horizontal cavity 407, and the second vertical cavity 408 is in a completely sealed state.

[0059] As the shaft 1 continues to drive the rotating ring 3 to rotate in the first direction, the moving piston 15 moves obliquely upward along the first inclined surface 181 of the stepped protrusion 18. The second spring 14 is gradually compressed, and the portion of the moving piston 15 extending into the second vertical cavity 408 gradually increases. During this process, the volume of the sealing cavity is rapidly compressed, causing the lubricating oil in the sealing cavity to push open the oil discharge ball core 17. The oil discharge ball core 17 disengages from the cylindrical cavity, and the lubricating oil enters the flow channel cavity 409 from the sealing cavity and passes through the oil outlet cavity 410 and the return mechanism in sequence, finally flowing into the bearing chamber.

[0060] As the shaft 1 continues to drive the rotating ring 3 to rotate in the first direction, the moving piston 15 disengages from the first inclined surface 181 of the stepped protrusion 18 and enters the top surface 182 of the stepped protrusion 18. At this time, both the oil inlet piston 13 and the moving piston 15 act on the top surface 182 of the stepped protrusion 18. The oil inlet hole of the oil inlet piston 13 extends into the first vertical cavity 406, and the second vertical cavity 408 is blocked by the moving piston 15. Under the action of the third spring 16, the oil discharge ball core 17 is tightly attached to the cylindrical cavity at the connection between the horizontal cavity 407 and the flow channel cavity 409, thereby blocking the cylindrical cavity. Therefore, a sealed cavity is formed again between the first vertical cavity 406, the horizontal cavity 407, and the second vertical cavity 408, and the pressure in this cavity is stable. That is, it returns to... Figure 10 The state shown.

[0061] In this embodiment, the reflux mechanism includes a reflux pipe, such as... Figure 1 As shown, an oil drain connector 10 is sealed and installed on the outer circumference of the stationary ring 4 at the outlet of the oil outlet chamber 410. One end of the return pipe is connected to the oil drain connector 10, and the other end is connected to the bearing chamber of the reducer.

[0062] The automatic lubricating oil circulation mechanism in this embodiment requires no external power and relies on its own structural design to complete the oil discharge. The discharge effect is good, with 1-2 ml of oil discharged at a time. Moreover, a small amount of oil is always present in the oil tank, which can provide a certain sealing effect and prevent the intrusion of external dust and water. The discharged lubricating oil can flow back to the bearing chamber of the reducer through the return pipe. Even when the output shaft is running continuously, there is no need to add lubricating oil separately, realizing recycling.

[0063] In this embodiment, the number of stepped protrusions 18 is not specifically limited and can be reasonably set according to the specific conditions of the reducer on site. Of course, the number of stepped protrusions 18 should not be too large. If the number is too large, the oil discharge efficiency per unit time will be too high, and the amount of lubricating oil in the sealing gap between the moving ring 3 and the stationary ring 4 will be too small, which is not conducive to the sealing between the moving ring 3 and the stationary ring 4. In this embodiment, preferably, three stepped protrusions 18 are provided, and the three stepped protrusions 18 are evenly arranged on the inner bottom wall of the annular groove 301 around the axis of the moving ring 3.

[0064] It is important to note that because the output shaft is located below the reducer, the reducer has a high oil level and high oil pressure. Under the influence of gravity and oil pressure, the lubricating oil easily flows along the output shaft and seeps into the sealing gap between the rotating ring 3 and the stationary ring 4. Traditional mechanical seal structures do not fully consider the strong gravity-induced oil discharge effect when the output shaft is installed vertically, making it difficult to achieve an effective sealing effect.

[0065] In this embodiment, the sealing device for the output shaft of the rolling mill reducer is as follows: Figure 1As shown, when the moving ring 3 and the stationary ring 4 are engaged, the oil groove mentioned above is formed between the moving ring 3 and the stationary ring 4. The oil groove includes a labyrinth channel 5, an oil suction channel and a sealing channel that are connected in sequence. The channel formed between the annular groove 301 and the annular protrusion 405 is the oil suction channel.

[0066] The maze passage 5 has multiple bends and is located outside the oil suction passage. The end of the maze passage 5 away from the oil suction passage is connected to the external environment, and the end of the sealed passage away from the oil suction passage is connected to the space located inside the moving ring 3.

[0067] In this embodiment, the outermost labyrinth channel 5 has multiple bends. Due to its special labyrinth structure, it can prevent large external dust particles from entering the sealing gap between the moving ring 3 and the stationary ring 4. In addition, water or oil needs to undergo multiple changes in direction and throttling when passing through, which greatly increases the resistance to leakage of water or oil, thereby effectively improving the sealing performance and minimizing the leakage of lubricating oil. It is especially suitable for sealing under harsh conditions such as high speed, high pressure, and high temperature.

[0068] In some embodiments, such as Figure 1 As shown, a micro-protrusion structure 6 is provided on the inner wall of the sealed channel.

[0069] The function of the micro-protrusion structure 6 is to increase the contact area: the micro-protrusion structure 6 formed by electroplating or spraying can increase the microscopic contact area of ​​the sealing contact surface, thereby improving the sealing effect. These micro-protrusions form a series of tiny contact points on the contact surface, making the sealing surface fit more tightly at the microscopic level and reducing leakage channels.

[0070] Improved lubrication conditions: The micro-protrusion structure 6 can also improve the lubrication conditions of the sealing contact surface. The lubricating medium can form a tiny lubricating film between the micro-protrusions, reducing friction and wear between the sealing surfaces, and also helping to lower the temperature of the sealing contact surface.

[0071] In some embodiments, a skeleton oil seal 7 is also provided on the inner wall of the sealing channel. The skeleton oil seal 7 is a skeleton-type dustproof oil seal. Under the action of the self-tightening spiral spring, the sealing lip of the skeleton-type dustproof oil seal forms a tight contact with the inner wall of the sealing channel to achieve a sealing effect.

[0072] In some embodiments, two skeleton oil seals 7 are provided, arranged along the axial direction of the rotating ring 3. The two skeleton oil seals 7 are close to the inner side of the rotating ring 3 and the stationary ring 4, forming a sealed cavity between the two skeleton oil seals 7. The purpose of providing two skeleton oil seals 7 is to prevent oil contaminants inside the reducer from entering the sealed channel, thus preventing oil contaminants from entering the oil sump.

[0073] In some embodiments, a lubricant, such as graphite or grease, is added to the sealing cavity between the two skeleton oil seals 7 to ensure the lubrication effect of the skeleton oil seals 7.

[0074] As can be seen, the sealing device for the output shaft of the rolling mill reducer in this embodiment greatly improves the sealing performance through the synergistic effect of multiple sealing structures, making it more adaptable, more durable, and ensuring the service life of the sealing device.

[0075] It should be clarified that during the long-term continuous operation of a large reducer, if the aforementioned skeleton oil seal 7 is operating normally, it can prevent lubricating oil from entering the oil sump. However, if the skeleton oil seal 7 is severely worn, it will no longer be able to prevent lubricating oil from entering the oil sump. Moreover, due to various production reasons, the sealing structure is generally not replaced by stopping the machine; the oil leakage is simply allowed to persist until the next major overhaul cycle.

[0076] In this embodiment, once the skeleton oil seal 7 is severely worn and a large amount of lubricating oil enters the oil trough, the oil can be automatically drained by the automatic lubricating oil circulation mechanism.

[0077] As can be seen, in this embodiment, the sealing performance of the sealing device is greatly improved and the occurrence of oil leakage is reduced through the synergistic effect of multiple sealing structures. Once the skeleton oil seal 7 fails, the lubricating oil will penetrate into the sealing gap between the moving ring 3 and the stationary ring 4 under the action of gravity and oil pressure. At this time, the automatic lubricating oil circulation mechanism will automatically complete the oil drainage work, thereby avoiding the occurrence of oil leakage.

[0078] Furthermore, multiple annular labyrinth grooves are provided on the end face of the moving ring 3 facing the stationary ring 4. The labyrinth grooves are coaxially arranged with the moving ring 3, and the diameters of the multiple labyrinth grooves decrease sequentially along the radial direction of the moving ring 3. That is, from the outer side to the inner side of the moving ring 3, the diameters of the multiple labyrinth grooves decrease sequentially. Multiple labyrinth protrusions are provided on the end face of the stationary ring 4 facing the moving ring 3, each corresponding to one of the labyrinth grooves. The width of the labyrinth protrusion is smaller than the width of the corresponding labyrinth groove, and the labyrinth channel 5 is formed between the labyrinth groove and the labyrinth protrusion.

[0079] In this embodiment, the micro-protrusion structure 6 formed by electroplating can be formed on the side of the sealing channel located on the moving ring 3, or on the side of the sealing channel located on the stationary ring 4, or electroplating can be performed on both the side of the sealing channel located on the moving ring 3 and the side of the sealing channel located on the stationary ring 4.

[0080] Furthermore, it's important to understand that skeleton-type dust seals, with their metal skeleton, provide additional strength and rigidity, enabling them to adapt to various working environments and conditions, including high temperatures, low temperatures, and high pressures. They also exhibit excellent heat resistance, cold resistance, and pressure resistance. Moreover, due to their structural design and material selection, skeleton-type dust seals can maintain good sealing performance over extended periods, reducing the frequency of replacement and maintenance.

[0081] In this embodiment, a sealing ring 8 is provided on the inner wall of the moving ring 3. The sealing ring 8 is made of polytetrafluoroethylene (PTFE). PTFE is almost insoluble in all solvents and has the characteristics of being resistant to acids, alkalis, and various organic solvents. It can be used for a long time at temperatures ranging from -180 to 260°C and has excellent heat and cold resistance. Therefore, the sealing ring 8 can maintain stable performance in high-temperature and oily environments.

[0082] As can be seen, this embodiment uses a combination of multiple sealing structures to achieve sealing. The synergistic effect of these multiple sealing structures greatly improves the sealing performance.

[0083] It should be noted that the metal surfaces of the rotating ring 3 and the stationary ring 4 are prone to corrosion in humid environments, and contaminants adhering to the rotating ring 3 and the stationary ring 4 will accelerate the wear of the sealing surface.

[0084] To address this technical problem, in this embodiment, the metal surfaces of the rotating ring 3 and the stationary ring 4 are first subjected to surface hardening treatment (such as nitriding or chrome plating), with a hardened layer thickness of 0.05-0.1 mm. Then, a wear-resistant and corrosion-resistant special coating (such as a ceramic coating or a nano-coating) is uniformly sprayed onto the surfaces of the rotating ring 3 and the stationary ring 4, with a coating thickness of 0.1-0.3 mm. Finally, a fluorosilicone nano-coating with a contact angle >150° is sprayed onto the outermost layer to prevent water and oil adhesion. This significantly improves the durability of the seal in dusty and oily environments, reduces seal failure caused by surface wear, enhances the seal's anti-contamination ability, and makes it suitable for high-dust and high-humidity environments.

[0085] To prevent external dust from entering and clogging the maze passage 5, a purging mechanism is installed. This mechanism includes a compressor, pretreatment equipment, an air tank, compressed air purging nozzles 11, and a purging channel 403 located within the stationary ring 4. One end of the purging channel 403 is connected to the maze passage 5, and the other end is connected to the external environment. The compressed air purging nozzles 11 are sealed and installed at the end of the purging channel 403 furthest from the maze passage 5. The compressor, pretreatment equipment, and air tank are sequentially connected by pipes. The air tank and the compressed air purging nozzles 11 are connected by an outlet pipe, on which a pressure valve and a switching valve are installed.

[0086] Thus, the compressor compresses outside air into high-pressure gas, and then sends this compressed air to a pretreatment device. The pretreatment device filters, cools, dries, and removes oil from the compressed air to remove impurities and moisture, preventing impurities and moisture from entering between the moving ring 3 and the stationary ring 4. The pretreated compressed air is then sent to an air storage tank for storage. The compressed air in the air storage tank is then sent to the compressed air purging nozzle 11 through the outlet pipe and ejected from the compressed air purging nozzle 11.

[0087] Regular purging in this way can blow out some of the dust within the maze passage 5, preventing dust blockage. It should be noted that the outermost part of the maze passage 5 is usually more prone to blockage; therefore, the end of the purging channel 403 should be close to the outlet of the maze passage 5 and the dust should be blown outwards from the inside. Furthermore, in this embodiment, there is no specific limitation on the number of purging channels 403 and compressed air purging nozzles 11; they can be selected reasonably according to actual conditions. For example, six purging channels 403 can be set, evenly arranged around the axis of the stationary ring 4, with one compressed air purging nozzle 11 installed at the air inlet of each purging channel 403. These six compressed air purging nozzles 11 are supplied with air from the same air storage tank.

[0088] In addition, the blowing angle of the blowing channel 403 can be reasonably set, for example, blowing outward at an angle will result in a better blowing effect.

[0089] In this embodiment, a temperature detection mechanism is installed on the stationary ring 4. The temperature detection mechanism includes a temperature measurement channel 402, a temperature sensor, a microprocessor, a wireless transmitter, and a power module. The temperature measurement channel 402 is located inside the stationary ring 4 and one end of the temperature measurement channel 402 is connected to the external environment. The temperature detection connector is sealed and installed at one end of the temperature measurement channel 402, and the temperature sensor is installed inside the temperature measurement channel 402.

[0090] The temperature sensor converts temperature changes into electrical signals. The signal processing circuit amplifies, filters, and performs analog-to-digital (A / D) conversion on the weak electrical signal output from the temperature sensor to facilitate subsequent wireless transmission. The microprocessor receives the digital signal from the signal processing circuit, processes and encodes it further, and prepares it for transmission to the wireless transmitter. The wireless transmitter uses various communication protocols, such as Wi-Fi, Bluetooth, Zigbee, LoRa, and cellular networks, to send data to the control center or controller in the form of wireless signals. The power module supplies power to all electrical components.

[0091] When bearing 2 is severely worn or has poor lubrication, the shaft 1 will rapidly heat up during its rapid rotation. Since both the rotating ring 3 and stationary ring 4 are metal parts, their temperatures will also rise rapidly. Stationary ring 4, in particular, heats up quickly because it is in direct contact with bearing 2, typically reaching 60℃-80℃ within minutes. Furthermore, the rolling mill will trigger an alarm if the bearing temperature exceeds 60℃, and will require shutdown if it exceeds 90℃.

[0092] In this application, the temperature of the stationary ring 4 is measured by a temperature detection mechanism. When the measured temperature value exceeds the threshold, it indicates that the bearing 2 is severely worn or has poor lubrication. At this time, lubricating oil should be added to the bearing chamber in time or the machine should be stopped in time.

[0093] Furthermore, a pressure detection mechanism is also installed on the static ring 4. The pressure detection mechanism includes a pressure detection connector, a pressure measurement channel 404, a pressure sensor, a microprocessor, a wireless transmitter, and a power module. The first end of the pressure measurement channel 404 is connected to the sealed channel, and the second end is connected to the external environment. The pressure detection connector is sealed and installed at the second end of the pressure measurement channel 404. The pressure sensor and the pressure detection connector are connected via line communication.

[0094] It should be noted that the operating pressure has a significant impact on the sealing performance. If the pressure in the oil groove between the rotating ring 3 and the stationary ring 4 is too high, it may damage the internal micro-protrusion structure 6 and the skeleton oil seal 7, thereby causing leakage. Conversely, if the pressure is too low, it may lead to a poor seal and fail to effectively prevent media leakage. Therefore, in this embodiment, the pressure sensor monitors changes in internal pressure to determine whether the seal is in normal working condition.

[0095] In this application, the pressure sensor converts the pressure change between the moving ring 3 and the stationary ring 4 into an electrical signal, the signal processing circuit amplifies, filters and performs A / D conversion on the electrical signal, the microprocessor receives the digital signal, encodes and packages it, and the wireless transmitter sends the encoded data out through a wireless signal.

[0096] The power management module provides a stable power supply for the entire system. The control center or controller receives wireless signals, decodes and processes the data to achieve monitoring and control.

[0097] In this way, the pressure change between the moving ring 3 and the stationary ring 4 can be detected in real time, and the current seal can be judged based on the measured pressure value.

[0098] Optionally, the pressure sensor is a MEMS pressure sensor (accuracy ±0.1%FS), and the temperature sensor is a fiber optic temperature sensor (temperature range -50℃ to 300℃).

[0099] In the description of this utility model, it should be noted that the terms "upper" and "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0100] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0101] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A sealing device for the output shaft of a rolling mill reducer, characterized in that, The mill bearing sealing device is sleeved on the vertically arranged shaft (1). The mill bearing sealing device includes a rotating ring (3), a stationary ring (4), and an automatic lubricating oil circulation mechanism. The rotating ring (3) is lower than the stationary ring (4), and an oil groove is formed between the rotating ring (3) and the stationary ring (4). The automatic lubricating oil circulation mechanism includes an automatic oil suction and discharge mechanism and a return mechanism. The automatic oil suction and discharge mechanism includes an oil discharge channel (401) provided on the stationary ring (4) and an oil suction and discharge structure. The oil discharge channel (401) includes an oil inlet and discharge chamber and an oil discharge chamber. The oil inlet and discharge chamber includes a first vertical chamber (406), a horizontal chamber (407), and a second vertical chamber (408). The first vertical cavity (406) and the second vertical cavity (408) are vertically disposed on the stationary ring (4). The two ends of the horizontal cavity (407) are respectively connected to the top ends of the first vertical cavity (406) and the second vertical cavity (408). The ends of the first vertical cavity (406) and the second vertical cavity (408) away from the horizontal cavity (407) are connected to the oil groove. One end of the oil discharge cavity is connected to the horizontal cavity (407), and the other end is connected to the return mechanism. The end of the return mechanism away from the oil discharge cavity is connected to the bearing chamber. The oil suction and discharge structure includes a third spring (16), an oil discharge ball core (17), a first piston structure, a second piston structure, and multiple stepped protrusions (18); the first piston structure and the second piston structure are respectively installed in the first vertical cavity (406) and the second vertical cavity (408), the third spring (16) is vertically installed in the oil discharge cavity, the oil discharge ball core (17) is fixed to the bottom end of the third spring (16), and the stepped protrusions (18) are provided on the inner bottom wall of the oil groove; The first piston structure and the second piston structure cooperate with the stepped protrusion (18) to change the pressure in the oil inlet and outlet chambers; when the mill bearing sealing device is in the oil suction state, the oil in the oil groove flows into the oil inlet and outlet chamber from the oil inlet of the first piston structure; when the mill bearing sealing device is in the oil discharge state, under the action of pressure, the oil in the oil inlet and outlet chamber pushes open the oil discharge ball core (17) and enters the oil discharge chamber and flows back to the bearing chamber through the return mechanism.

2. A sealing device for the output shaft of a rolling mill reducer according to claim 1, characterized in that, The bottom surface of the stationary ring (4) has an annular protrusion (405) coaxial with it, and the top of the moving ring (3) is provided with an annular groove (301). The annular protrusion (405) extends into the annular groove (301). The first vertical cavity (406), the horizontal cavity (407), and the second vertical cavity (408) are disposed in the annular protrusion (405). The oil discharge cavity includes a connected flow channel cavity (409) and an oil outlet cavity (410). The flow channel cavity (409) is vertically arranged. The bottom end of the flow channel cavity (409) is connected to the transverse cavity (407) and one end of the oil outlet cavity (410) is connected to the top end of the flow channel cavity (409), and the other end is connected to the return mechanism. The top end of the third spring (16) is fixed to the inner wall of the flow channel cavity (409). The oil discharge ball core (17) acts on the connection between the flow channel cavity (409) and the transverse cavity (407) and is used to control the opening and closing of the connection.

3. A sealing device for the output shaft of a rolling mill reducer according to claim 2, characterized in that, The first piston structure includes a first spring (12) and an oil inlet piston (13). The top end of the first spring (12) is fixed to the inner top wall of the first vertical cavity (406). The length of the first spring (12) is less than the length of the first vertical cavity (406). The oil inlet piston (13) is fixed to the bottom end of the first spring (12). The oil inlet piston (13) is provided with an oil inlet hole.

4. A sealing device for the output shaft of a rolling mill reducer according to claim 3, characterized in that, The second piston structure includes a second spring (14) and a movable piston (15). The top end of the second spring (14) is fixed to the inner top wall of the second vertical cavity (408), and the movable piston (15) is fixed to the bottom end of the second spring (14). The length of the second spring (14) is less than the length of the second vertical cavity (408).

5. A sealing device for the output shaft of a rolling mill reducer according to claim 4, characterized in that, The step protrusion (18) is in the shape of an isosceles trapezoid, comprising a first inclined surface (181), a top surface (182), and a second inclined surface (183) connected in sequence; the direction from the first inclined surface (181) to the second inclined surface (183) is the length direction of the step protrusion (18), and the width direction of the step protrusion (18) is the same as the radial direction of the moving ring (3).

6. A sealing device for the output shaft of a rolling mill reducer according to claim 5, characterized in that, When the first piston structure and the second piston structure are respectively offset from the stepped protrusion (18), under the action of the first spring (12), the top end of the oil inlet piston (13) is located in the first vertical cavity (406), and its bottom end acts on the inner bottom wall of the annular groove (301), and the oil inlet hole on the oil inlet piston (13) extends out of the first vertical cavity (406); under the action of the second spring (14), the top end of the moving piston (15) is located in the second vertical cavity (408), and its bottom end acts on the inner bottom wall of the annular groove (301).

7. A sealing device for the output shaft of a rolling mill reducer according to claim 6, characterized in that, The sum of the length of the first spring (12) in its natural state and the length of the oil inlet piston (13) is greater than the distance between the top surface (182) of the stepped protrusion (18) and the inner top wall of the first vertical cavity (406); the sum of the length of the second spring (14) in its natural state and the length of the moving piston (15) is greater than the distance between the top surface (182) of the stepped protrusion (18) and the inner top wall of the second vertical cavity (408).

8. A sealing device for the output shaft of a rolling mill reducer according to claim 1, characterized in that, Multiple stepped protrusions (18) are evenly arranged around the axis of the moving ring (3).

9. A sealing device for the output shaft of a rolling mill reducer according to claim 2, characterized in that, The reflux mechanism includes a reflux pipe, one end of which is connected to the end of the oil outlet chamber (410) away from the flow channel chamber (409), and the other end of which is connected to the bearing chamber.

10. A sealing device for the output shaft of a rolling mill reducer according to claim 2, characterized in that, The bottom opening of the flow channel cavity (409) and the transverse cavity (407) are connected by a cylindrical cavity. The diameter of the oil discharge ball core (17) is larger than the diameter of the cylindrical cavity, and the diameter of the oil discharge ball core (17) is smaller than the diameter of the flow channel cavity (409).

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