Sealing structure

Abstract

The utility model relates to the technical field of shaft sealing, in particular to a sealing structure which comprises a box body, a rotating shaft, a check ring and a gland, a left-right through rotating hole is formed in the right side of the box body, and the right end of the rotating shaft penetrates through the rotating hole and then is located on the right side of the box body. According to the utility model, the structure is reasonable and compact, the plurality of labyrinth grooves are arranged, and a plurality of zigzag small chambers are arranged between the rotating shaft and the inner wall of the sealing hole of the gland, so that the leakage is reduced, and the lubricating liquid in the box body generates a throttling effect after passing through the labyrinth grooves, so that the leakage prevention purpose is achieved; oil in the labyrinth groove can flow into the box body through the oil return groove, leakage of the oil is reduced, resistance of the oil flowing towards the right end of the rotating shaft can be increased by arranging the check ring, part of the oil on the surface of the rotating shaft can be made to flow back into the oil return groove in a branch mode and finally flow back into the box body, leakage of the oil is reduced, lubricating oil is saved, and therefore field leakage points are reduced. On-site greasy dirt is reduced, equipment operation environment is improved, and maintenance cost and difficulty are reduced.

Description

Technical Field

[0001] This utility model relates to the field of shaft sealing technology and is a sealing structure. Background Technology

[0002] Centrifugal pump bearing housings typically employ a non-contact labyrinth seal structure. This structure is reliable and effectively saves on operation and maintenance costs. However, some centrifugal pumps' labyrinth shaft seals suffer from persistent leakage problems due to excessive sealing gaps or insufficient airflow resistance, which are difficult to eliminate effectively. This not only wastes lubricating oil but also makes on-site oil stains difficult to clean, increasing maintenance difficulty and costs.

[0003] When the rotating shaft is stationary, the lubricating oil is immersed in the oil sump of the bearing housing. After the shaft rotates, some oil splashes into droplets or mist, while some remains as an oil film on the bearing and shaft. Therefore, the gap between the rotating shaft and the bearing housing cover becomes the most prone to oil leakage. Commercially available solutions typically use a combined structure of oil baffle ring, bearing side cover, packing, and cover adjustment for sealing, utilizing the oil baffle ring for sealing, oil blocking, and packing for fastening to achieve a sealing effect. However, the oil film and droplets on the rotating shaft accumulate due to its rotation and wet the bearing housing cover. Without effective protective measures, lubricating oil will leak out from the gap between the rotating shaft and the bearing housing cover. Utility Model Content

[0004] This invention provides a sealing structure that overcomes the shortcomings of the prior art and can effectively solve the problem of leakage in existing labyrinth sealing structures that is difficult to eliminate.

[0005] The technical solution of this utility model is achieved through the following measures: a sealing structure, including a housing, a rotating shaft, a retaining ring, and a pressure cap. The right side of the housing is provided with a rotating hole that runs through the left and right sides. The right end of the rotating shaft passes through the rotating hole and is located on the right side of the housing. A pressure cap is fixedly installed on the right side of the housing corresponding to the position of the rotating hole. A sealing hole for the rotating shaft to pass through is provided in the center of the right end of the pressure cap. Several annular labyrinth grooves with inward openings are provided on the inner wall of the sealing hole at intervals on the left and right sides. A return oil groove with an opening to the left is provided at the lower left end of the pressure cap. The upper part of the return oil groove is connected to the lower part of the leftmost labyrinth groove. A retaining ring is fixedly installed on the outer side of the rotating shaft corresponding to the position of the left end of the sealing hole.

[0006] The following are further optimizations and / or improvements to the above-mentioned utility model technical solution:

[0007] The outer side of the output shaft at the position between the right end of the retaining ring and the pressure cap can be provided with a spiral groove, the groove being either left-handed or right-handed.

[0008] An annular gap may be provided between the inner wall of the sealing hole and the outer side of the rotating shaft, and the annular gap is smaller than the height of the retaining ring.

[0009] The left end of the aforementioned pressure cap can be fixed with an annular pressure ring, which is fitted between the inner side of the rotating hole and the outer side of the rotating shaft.

[0010] This utility model has a reasonable and compact structure. By setting multiple labyrinth grooves, there are many tortuous small chambers between the inner wall of the rotating shaft and the sealing hole of the pressure cap, which reduces leakage. The lubricating fluid in the box will have a throttling effect after passing through the labyrinth grooves, thus achieving the purpose of preventing leakage. By setting an oil return groove, the oil in the labyrinth grooves can flow into the box through the oil return groove, reducing oil leakage. By setting a retaining ring, the resistance to the flow of oil to the right end of the rotating shaft can be increased, and some of the oil on the surface of the rotating shaft can be diverted back to the oil return groove, and finally flow back into the box, reducing oil leakage, saving lubricating oil, thereby reducing on-site leakage points, reducing on-site oil pollution, improving the equipment operating environment, and reducing maintenance costs and difficulties. Attached Figure Description

[0011] Appendix Figure 1 These are schematic diagrams of partial cross-sectional views of embodiments one to five of this utility model.

[0012] Appendix Figure 2 This is a three-dimensional structural diagram of the rotating shaft in embodiments one to five of this utility model.

[0013] Appendix Figure 3 This is a schematic diagram of the left-side structure of the pressure cap in embodiments one to five of this utility model.

[0014] Appendix Figure 4 This is a three-dimensional structural diagram of the pressure cap in embodiments one to five of this utility model.

[0015] The codes in the attached diagram are as follows: 1 is the housing, 2 is the rotating shaft, 3 is the pressure cap, 4 is the retaining ring, 5 is the rotating hole, 6 is the sealing hole, 7 is the labyrinth groove, 8 is the oil return groove, 9 is the groove, 10 is the keyway, and 11 is the pressure ring. Detailed Implementation

[0016] This utility model is not limited to the following embodiments, and the specific implementation method can be determined according to the technical solution of this utility model and the actual situation.

[0017] In this utility model, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 1 The orientation of the layout is determined by the direction of the map.

[0018] The present invention will be further described below with reference to the embodiments and accompanying drawings:

[0019] Example 1: As shown in the attached document Figures 1 to 4As shown, the sealing structure includes a housing 1, a rotating shaft 2, a retaining ring 4, and a pressure cap 3. The right side of the housing 1 has a rotating hole 5 that runs through the left and right sides. The right end of the rotating shaft 2 passes through the rotating hole 5 and is located on the right side of the housing 1. The pressure cap 3 is fixedly installed on the right side of the housing 1 corresponding to the position of the rotating hole 5. The center of the right end of the pressure cap 3 has a sealing hole 6 for the rotating shaft 2 to pass through. Several annular labyrinth grooves 7 with openings facing inward are provided on the inner wall of the sealing hole 6 at intervals on the left and right sides. The lower left end of the pressure cap 3 has an oil return groove 8 with an opening facing left. The upper part of the oil return groove 8 is connected to the lower part of the leftmost labyrinth groove 7. The retaining ring 4 is fixedly installed on the outer side of the rotating shaft 2 corresponding to the position of the left end of the sealing hole 6.

[0020] According to the requirements, an annular groove is provided on the outer side of the rotating shaft 2 at the left end of the corresponding sealing hole 6. The retaining ring 4 can be a known retaining ring 4 (shaft elastic retaining ring) or a retaining ring or an oil retaining ring. The retaining ring 4 can also be made of high-strength, corrosion-resistant alloy steel, such as 10NiCr5-4 alloy steel or 25CrMoS4 alloy steel. The cross section of the retaining ring 4 can be circular or rectangular. After the retaining ring 4 is tightly clamped in the annular groove, it is fixedly installed together with the rotating shaft 2. This can adapt to various working environments and facilitate the disassembly and assembly of the retaining ring 4 and the rotating shaft 2. The housing 1 can be a known bearing housing. The bearing housing is filled with lubricating fluid. The rotating shaft 2 is an output shaft. The right end of the rotating shaft 2 can be driven to a known water pump impeller or fan impeller. The sealing structure in this embodiment is used for the bearing housing of a centrifugal pump.

[0021] During use, by setting multiple labyrinth grooves 7, there are many tortuous small chambers between the inner wall of the sealing hole 6 of the rotating shaft 2 and the pressure cover 3, which reduces leakage. The lubricating fluid in the housing 1 generates a throttling effect after passing through the labyrinth grooves 7, thus achieving the purpose of preventing leakage. By setting an oil return groove 8, the oil in the labyrinth grooves 7 can flow into the housing 1 through the oil return groove 8, reducing oil leakage. By setting a retaining ring 4, the resistance to the flow of oil to the right end of the rotating shaft 2 can be increased, and some of the oil on the surface of the rotating shaft 2 can be diverted to the oil return groove 8 and finally flow back into the housing 1, reducing oil leakage, saving lubricating oil, thereby reducing on-site leakage points, reducing on-site oil pollution, improving the equipment operating environment, and reducing maintenance costs and difficulties.

[0022] The above sealing structure can be further optimized and / or improved according to actual needs:

[0023] Example 2: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown, a spiral groove 9 is provided on the outer side of the output shaft at the position between the right end of the retaining ring 4 and the pressure cover 3. The direction of the groove 9 is left-handed or right-handed.

[0024] Depending on the requirements, the rotation direction of the groove 9 is opposite to the working direction of the rotating shaft 2. If the rotating shaft 2 rotates clockwise, the groove 9 rotates right-handed; conversely, if the rotating shaft 2 rotates counterclockwise, the groove 9 rotates left-handed. During use, a counter-spiral groove 9 is machined on the outside of the rotating shaft 2 to improve the backflow of liquid in the housing 1 and further reduce leakage.

[0025] Example 3: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown, an annular gap is provided between the inner wall of the sealing hole 6 and the outer side of the rotating shaft 2, and the annular gap is less than the height of the retaining ring 4.

[0026] Depending on the requirements, the height of the retaining ring 4 (the difference between the outer diameter of the retaining ring 4 and the outer diameter of the rotating shaft 2 inside the sealing hole 6) can be 0.1mm. When the liquid flows along the groove 9 to the left end, it falls under the blocking effect of the retaining ring 4 and finally flows back into the housing 1. The retaining ring 4 can increase the resistance of the oil flowing into the annular gap, reduce the sealing gap, and enhance the sealing performance.

[0027] Example 4: As an optimization of the above examples, as shown in the appendix. Figure 1 , 3 As shown in Figures 4 and 5, a ring-shaped pressure ring 11 is fixed to the left end of the pressure cap 3. The pressure ring 11 is fitted between the inner side of the rotating hole 5 and the outer side of the rotating shaft 2.

[0028] Depending on the requirements, the pressure ring 11 and the pressure cap 3 can be installed as a single unit. The pressure cap 3 has a circular or disc structure, and the oil return groove 8 is located on the left end of the pressure cap 3 inside the pressure ring 11. During use, the pressure ring 11 supports the outer ring end of the bearing installed between the inner wall of the sealing hole 6 and the outer side of the rotating shaft, thus limiting the bearing position. The liquid in the labyrinth groove 7 can flow into the housing 1 through the oil return groove 8, effectively reducing oil leakage, lowering the leakage rate, saving lubricating oil, and avoiding safety hazards caused by poor lubrication due to oil leakage. This ensures the normal operation of the equipment, reduces the workload of personnel adding lubricating oil, and improves maintenance efficiency.

[0029] Example 5: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown, a keyway 10 is provided on the outer side of the rotating shaft 2 corresponding to the right position of the pressure cover 3.

[0030] As required, the outer side of the rotating shaft 2 corresponding to the right position of the pressure cap 3 has a step, that is, the outer diameter of the rotating shaft 2 corresponding to the right position of the pressure cap 3 is smaller than the outer diameter of the rotating shaft 2 with the spiral groove 9. This facilitates the processing and manufacturing of the spiral groove 9. The keyway 10 can be oblong or rectangular. The keyway 10 facilitates the installation of a connecting key. The outer side of the right end of the rotating shaft 2 can be fitted with a conventionally known water pump impeller or fan impeller through the connecting key. In this way, the drive motor can transmit torque to the water pump impeller or fan impeller through the rotating shaft 2, driving the water pump impeller or fan impeller to rotate.

[0031] The above technical features constitute various embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A sealing structure, characterized in that... The device includes a housing, a rotating shaft, a retaining ring, and a pressure cap. The right side of the housing has a through-hole. The right end of the rotating shaft passes through the rotating hole and is located on the right side of the housing. A pressure cap is fixedly installed on the right side of the housing corresponding to the position of the rotating hole. A sealing hole for the rotating shaft to pass through is provided in the center of the right end of the pressure cap. Several annular labyrinth grooves with inward openings are provided on the inner wall of the sealing hole at intervals. A return oil groove with a left opening is provided at the lower left end of the pressure cap. The upper part of the return oil groove is connected to the lower part of the leftmost labyrinth groove. A retaining ring is fixedly installed on the outer side of the rotating shaft corresponding to the position of the left end of the sealing hole.

2. The sealing structure according to claim 1, characterized in that... A spiral groove is provided on the outer side of the output shaft at the position between the retaining ring and the right end of the pressure cover. The groove can rotate left or right.

3. The sealing structure according to claim 1 or 2, characterized in that... An annular gap is provided between the inner wall of the sealing hole and the outer side of the rotating shaft, and the annular gap is smaller than the height of the retaining ring.

4. The sealing structure according to claim 1 or 2, characterized in that... A ring-shaped pressure ring is fixed to the left end of the pressure cap, and the pressure ring is fitted between the inner side of the rotating hole and the outer side of the rotating shaft.

5. The sealing structure according to claim 3, characterized in that... A ring-shaped pressure ring is fixed to the left end of the pressure cap, and the pressure ring is fitted between the inner side of the rotating hole and the outer side of the rotating shaft.

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