Bearing bush oil sealing structure of sliding bearing

Abstract

The utility model discloses a bearing bush oil sealing structure of a sliding bearing, which comprises a shaft, a bearing bush box, a bearing bush and an air blowing chamber, the shaft penetrates through the bearing bush box, the bearing bush is arranged in the bearing bush box, a second sealing packing is arranged on the right side of the bearing bush box, and a second sealing ring is arranged on the inner side of the second sealing packing. A third sealing packing is arranged on the right side of the second sealing packing, an air sealing cavity is formed between the second sealing packing and the third sealing packing, an air guide wing is arranged in the air sealing cavity and is in a conical trumpet shape, and a trumpet-shaped large opening of the air guide wing is in threaded connection with the side face, close to the bearing bush, of the interior of the third sealing packing; a trumpet-shaped small opening of the air guide wing is obliquely opposite to the direction of the second sealing ring; the structure is simple in design and low in improvement cost, positive pressure gas is introduced into the gap between the inner ring of the sealing ring and the shaft through the blowing chamber, and the oil gas pressure in the bearing bush chamber is kept in a slightly positive pressure state, so that the oil gas can be prevented from overflowing into a motor body from the fit gap between the second sealing ring and the motor shaft.

Description

Technical Field

[0001] The utility model relates to the technical field of motor oil retainer sealing, in particular to a bushing oil sealing structure of a sliding bearing. Background Art

[0002] In recent years, box-type slip ring end cover bearings have to withstand huge negative pressure caused by the motor rotor fan. The huge negative pressure will cause the oil in the bearing cavity to be sucked out and atomized along the gap between the rotating shaft and the bearing cover, and finally condense into oil droplets at the rotor fan, the end of the stator and rotor coil, etc. The main reason for oil leakage is that when the motor is running, the suction force generated by the fan blades on the rotor in the motor housing causes negative pressure in the annular gap between the motor housing and the bearing box, and the negative pressure in the annular gap causes the lubricating oil in the bearing box to leak. The motor rotor is a rotating part with a large moment of inertia. The bearing oil ring throws up the lubricating oil in the oil groove and is then dispersed by the flowing gas to form finer oil droplets and oil mist. At the same time, as the motor runs, the oil temperature and the bearing temperature will also increase accordingly, so that positive pressure is generated inside the bearing box, prompting the oil mist to escape with the flow of air and leak into the motor housing. Oil leakage will seriously affect the surrounding environment, and the excessive oil covering the motor stator will seriously affect the heat dissipation of the motor, thereby accelerating the motor winding coil and reducing the insulation performance, which brings great hidden dangers to safe and civilized production. Utility Model Content

[0003] The technical problem to be solved by the utility model is to overcome the existing defects and provide a bearing oil sealing structure for a sliding bearing. Positive pressure gas is introduced into the gap between the inner ring of the sealing ring and the shaft through a blowing chamber, so that the oil and gas pressure in the bearing chamber is maintained in a slightly positive pressure state. In this way, the oil and gas can be sealed from overflowing into the motor body from the matching gap between the second sealing ring and the motor shaft, reducing the influence of the oil and gas on the inside of the motor, and can effectively solve the problems in the background technology.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a bearing oil sealing structure for a sliding bearing, comprising a shaft, a bearing box, a bearing and a blowing chamber, the shaft passing through the bearing box, a bearing is arranged inside the bearing box, a second sealing packing is arranged on the right side of the bearing box, a second sealing ring is arranged on the inner side of the second sealing packing, a third sealing packing is arranged on the right side of the second sealing packing, an air-sealed cavity is arranged between the second sealing packing and the third sealing packing, an air-guide wing is arranged in the air-sealed cavity, the air-guide wing is in a conical trumpet shape, the trumpet-shaped large mouth of the air-guide wing is screwed to the side of the inner part of the third sealing packing close to the bearing, the trumpet-shaped small mouth of the air-guide wing is arranged obliquely opposite to the direction of the second sealing ring, and a gap is left between the second sealing packing, a third sealing ring is arranged on the inner side of the third sealing packing, and a blowing chamber is arranged on the right side of the third sealing packing.

[0005] Furthermore, the second sealing packing is screwed to the side of the end cover of the bearing housing, and the third sealing packing and the blowing chamber are screwed to the outer peripheral side of the second sealing packing by long screws.

[0006] Furthermore, the large opening of the air guide wing has a flange which is screwed through the through hole on the flange to the side of the third sealing packing near the bearing shell, and the small opening of the air guide wing is arranged obliquely to the sealing gap direction of the second sealing ring.

[0007] Furthermore, an air inlet pipe is connected to the blowing chamber, an air volume regulating valve is arranged at the air inlet of the air inlet pipe, and a wind shield plate is arranged on the shaft located in the blowing chamber.

[0008] Furthermore, it also includes an exhaust pipe, which is connected to the air-sealed cavity, and the lower half of the exhaust pipe is set as an oil leakage channel.

[0009] Furthermore, a first sealing packing is arranged on the left side of the bearing box, a first sealing ring is arranged in the centripetal circumferential groove of the first sealing packing, a second sealing ring is installed in the centripetal circumferential groove of the second sealing packing, a third sealing ring is installed in the centripetal circumferential groove of the third sealing packing, and the first sealing packing, the second sealing packing and the third sealing packing are concentric.

[0010] Furthermore, a ventilation pipe is connected to the bearing housing, and a breathing cap is arranged at the upper end of the ventilation pipe.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] 1. The structure is simple in design and has low modification cost. Positive pressure gas is introduced into the gap between the inner ring of the sealing ring and the shaft through the blowing chamber to keep the oil and gas pressure in the bearing chamber slightly positive. In this way, the oil and gas can be sealed from overflowing into the motor body from the matching gap between the second sealing ring and the motor shaft, reducing the impact of the oil and gas on the inside of the motor.

[0013] 2. The wind shield plate prevents excessive loss of air volume from being blown into the third sealing ring to the air guide wing. The setting of the air guide wing plays a role in guiding the high-pressure gas from the blowing chamber, and evenly distributes the oil mist to the outer cavity of the air seal cavity and then transfers it to the exhaust duct, avoiding the disadvantage that the high-pressure gas in the air inlet pipe enters the air seal cavity and takes a shortcut to be discharged directly into the exhaust duct. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the utility model.

[0015] In the figure: 1 shaft, 2 first sealing ring, 3 first sealing packing, 4 bearing box, 5 breathing cap, 6 bearing, 7 ventilation pipe, 8 second sealing ring, 9 second sealing packing, 10 air inlet pipe, 11 air volume regulating valve, 12 third sealing packing, 13 blowing chamber, 14 wind shield plate, 15 third sealing ring, 16 wind guide wing, 17 air seal cavity, 18 exhaust pipe. DETAILED DESCRIPTION

[0016] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0017] See also Figure 1 The utility model provides a technical solution: a bearing oil sealing structure of a sliding bearing, comprising a shaft 1, a bearing box 4, a bearing 6 and a blowing chamber 13, the shaft 1 is passed through the bearing box 4, the bearing box 4 is provided with a bearing 6, the right side of the bearing box 4 is provided with a second sealing packing 9, the inner side of the second sealing packing 9 is provided with a second sealing ring 8, the right side of the second sealing packing 9 is provided with a third sealing packing 12, an air-sealing cavity 17 is provided between the second sealing packing 9 and the third sealing packing 12, and an air-sealing cavity 17 is provided with an air-guiding wing 16, the air-sealing cavity 17 is provided with an air-guiding wing 16, the setting of the air-guiding wing 16 plays a role in guiding the high-pressure gas from the blowing chamber 13, and evenly distributes the oil mist circumferentially to the outer cavity of the air-sealing cavity 17 and then transfers it to the exhaust pipe 18, so as to avoid the disadvantage that the high-pressure gas of the air inlet pipe 10 enters the air-sealing cavity 17 and takes a shortcut to be directly discharged into the exhaust pipe 18, The wing 16 is in a conical trumpet shape, and the large trumpet-shaped mouth of the air guide wing 16 is screwed on the side of the inner part of the third sealing packing 12 close to the bearing 6. The small trumpet-shaped mouth of the air guide wing 16 is set obliquely in the direction of the second sealing ring 8, and a gap is left between the second sealing packing 9. The gap facilitates the remaining air volume to pass from the inner periphery of the air guide wing 16 to the outer periphery, and the air volume on the outer periphery is discharged through the exhaust pipe 18. The inner side surface of the third sealing packing 12 is provided with a third sealing ring 15, and the third sealing ring 15 and the second sealing ring 8 play a sealing role. The specific principle is that the positive pressure air volume from the centrifugal fan inside the motor seals the oil mist of the third sealing ring 15 and the second sealing ring 8, suppresses the disadvantage of oil leakage due to suction in the traditional bearing structure, eliminates the leakage of lubricating oil, and ensures the normal operation of the rotating machinery. A blowing chamber 13 is provided on the right side of the third sealing packing 12.

[0018] The wind introduced from the outside is blown into the blowing chamber 13 after the air volume is adjusted by the air volume regulating valve 11, and then blown through the third sealing ring 15 to reach the inner cavity of the air guide wing 16. After the air volume is guided by the inner cavity of the air guide wing 16 to continue blowing the gap between the second sealing ring 8 and the shaft 1, the remaining air volume flows into the outer cavity of the air guide wing 16 and is discharged through the exhaust pipe 18.

[0019] The second sealing packing 9 is screwed to the side of the end cover of the bearing housing 4, and the third sealing packing 12 and the blowing chamber 13 are screwed to the outer peripheral side of the second sealing packing 9 by long screws.

[0020] The large opening of the air guide wing 16 has a flange which is screwed through the through holes on the flange to be screwed to the side of the third sealing packing 12 near the bearing bush 6 . The small opening of the air guide wing 16 is arranged obliquely to the sealing gap direction of the second sealing ring 8 .

[0021] The blowing chamber 13 is connected to an air inlet pipe 10, and an air volume regulating valve 11 is provided at the air inlet of the air inlet pipe 10. The air volume regulating valve 11 is used to adjust the wind flow rate in the air inlet pipe 10 to meet the use requirements. The shaft 1 located in the blowing chamber 13 is provided with a wind shield plate 14, which blocks most of the air from the air inlet pipe 10 from flowing back into the motor housing, that is to say, there is no excessive loss of air blown into the third sealing ring 15 to the wind guide wing 16.

[0022] The blowing chamber 13 is connected to the air source so that the wind flow rate inside the air inlet pipe 10 is adjusted to about 30m / s, the wind flow rate inside the wind guide wing 16 is adjusted to about 10m / s, and the wind flow rate inside the outlet of the exhaust pipe 18 is about 3m / s, so that the wind flow rate inside the breathing cap 5 on the sliding bearing is maintained at about 0.5m / s, thereby ensuring that the gas flow rate at each part is appropriate, effectively controlling the amount of air entering the bearing, so as to improve the sealing of the bearing shell 6 of the motor sliding bearing and effectively prevent oil leakage.

[0023] The exhaust pipe 18 is connected to the air-sealed cavity 17, and the lower half of the exhaust pipe 18 is arranged as an oil leakage passage. The exhaust pipe 18 not only has the function of balancing the atmosphere, but also has the function of leaking oil through the lower half of the pipe. The exhaust pipe 18 extends to the outside of the bearing seat; a small amount of oil leakage is collected in an oil storage barrel.

[0024] A first sealing packing 3 is arranged on the left side of the bearing box 4, a first sealing ring 2 is arranged in the centripetal circumferential groove of the first sealing packing 3, a second sealing ring 8 is installed in the centripetal circumferential groove of the second sealing packing 9, a third sealing ring 15 is installed in the centripetal circumferential groove of the third sealing packing 12, the first sealing packing 3, the second sealing packing 9 and the third sealing packing 12 are concentric, the sealing ring is installed by snap-fit, and is fixed radially and circumferentially in the groove, and the inner diameter of the sealing ring is slidingly fit with the shaft clearance.

[0025] The bearing housing 4 is connected with a ventilation pipe 7 , and a breathing cap 5 is arranged at the upper end of the ventilation pipe 7 . The function of the breathing cap 5 is to facilitate the timely condensation and reflux of the oil mist in the air ventilation pipe 7 .

[0026] The height of the vent pipe 7 is about 300 mm and the diameter is about 40 mm, which effectively prevents the oil mist in the bearing from flowing out of the air breathing cap because it cannot condense and reflux in time with the gas in the vent pipe 7; at the same time, the vent pipe 7 is raised and thickened and the breathing cap is enlarged, which is conducive to the timely condensation and reflux of the oil mist in the air vent pipe.

[0027] The wind introduced from the outside is positive pressure wind, and the wind source generally adopts the centrifugal wind force of the rotor fan blades inside the motor; the wind source of an independent blower can also be used; it is blown into the blowing chamber 13 through the air inlet pipe 10 and the air volume regulating valve 11, and the strong wind with a certain wind pressure blows through the third sealing ring 15 into the inner cavity of the air seal cavity 17 and the air guide wing 16. After the weakened wind volume continues to blow the gap between the second sealing ring 8 and the shaft 1 through the inner cavity of the air guide wing 16, the remaining wind returns to enter the outer cavity of the air guide wing 16 and is discharged through the exhaust pipe 18; the purpose of setting the air volume regulating valve 11 on the air inlet pipe 10 is to meet the requirements of the air seal oil leakage by adjusting the appropriate air volume and air pressure.

[0028] The pipeline of the air inlet pipe 10 is parallelly passed through the end cover and introduced into the dustproof sealing box of the first sealing packing 3 near the shaft end wind bearing 6, which seals the first sealing ring 2 air-tightly and can also solve the air-tight function of the first sealing ring 2; the wind pressure of the blowing chamber 13 blows air to the gap between the third sealing ring 15 in the third sealing packing 12 and the shaft 1, blocking the oil leakage, and then blows air to block the oil mist in the gap between the second sealing ring 8 in the second sealing packing 9 and the shaft 1; the third sealing ring 15 in the third sealing packing 12 can be taken out and replaced with other sealing ring sealing methods; the second sealing packing 9 has a through hole on its outer periphery and is screwed to the end cover on the right side of the bearing 6 through screws, and the third sealing packing 12 is screwed to the second sealing plate 6 in parallel with the blowing chamber 13 through a long screw through the hole The outer peripheral thread of the root 9; the setting of the wind guide wing 16 plays a role in guiding the high-pressure gas from the air inlet pipe 10 to be evenly distributed circumferentially to the air-sealed cavity 17 and then transferred to the exhaust pipe 18, thereby avoiding the disadvantage that the high-pressure gas from the air inlet pipe 10 enters the air-sealed cavity 17 and takes a shortcut to be directly discharged into the exhaust pipe 18; the wind guide wing 16 is located in the traditional air-sealed cavity 17, and the high-pressure gas from the air inlet pipe 10 compresses the oil mist and is discharged through the exhaust and oil leakage channels; the oil and gas in the air-sealed cavity 17 are affected by the pressurized air of the air inlet pipe 10, and will be discharged from the air inlet pipe 10 and the oil leakage channel, and the air pressure in the bearing housing is always kept in a slightly positive state; the oil inlet pipeline, the oil discharge pipe, and the oil leakage pipe are interconnected, and the exhaust device and the high-pressure oil supply device are prior art.

[0029] The basic principles, main features and advantages of the present invention are shown and described above. Without departing from the spirit and scope of the present invention, the present invention may also be subject to various changes and improvements, which are all within the scope of the present invention to be protected.

Claims

1. A bearing oil sealing structure for a sliding bearing, comprising a shaft (1), a bearing housing (4), a bearing (6) and a blowing chamber (13), characterized in that: The shaft (1) is inserted into a bearing housing (4), a bearing housing (6) is arranged inside the bearing housing (4), a second sealing packing (9) is arranged on the right side of the bearing housing (4), a second sealing ring (8) is arranged on the inner side of the second sealing packing (9), a third sealing packing (12) is arranged on the right side of the second sealing packing (9), an air sealing cavity (17) is arranged between the second sealing packing (9) and the third sealing packing (12), and an air guide wing (17) is arranged in the air sealing cavity (17). 16), the air guide wing (16) is in a conical trumpet shape, the trumpet-shaped large mouth of the air guide wing (16) is screwed to the inner side of the third sealing packing (12) close to the side of the bearing (6), the trumpet-shaped small mouth of the air guide wing (16) is arranged obliquely in the direction of the second sealing ring (8), and a gap is left between the air guide wing (16) and the second sealing packing (9), the inner side surface of the third sealing packing (12) is provided with a third sealing ring (15), and the right side of the third sealing packing (12) is provided with a blowing chamber (13).

2. The bearing oil sealing structure of a sliding bearing according to claim 1, characterized in that: The second sealing packing (9) is screwed to the side of the end cover of the bearing housing (4), and the third sealing packing (12) and the blowing chamber (13) are screwed to the outer peripheral side of the second sealing packing (9) by long screws.

3. The bearing oil sealing structure of a sliding bearing according to claim 1, characterized in that: The large opening of the air guide wing (16) has a flange which is screwed through a through hole on the flange to be screwed to the side of the third sealing packing (12) near the bearing bush (6). The small opening of the air guide wing (16) is arranged diagonally opposite to the sealing gap direction of the second sealing ring (8).

4. The bearing oil sealing structure of a sliding bearing according to claim 1, characterized in that: The blowing chamber (13) is connected to an air inlet pipe (10), an air volume regulating valve (11) is provided at the air inlet of the air inlet pipe (10), and a wind shield plate (14) is provided on the shaft (1) located in the blowing chamber (13).

5. The bearing oil sealing structure of a sliding bearing according to claim 1, characterized in that: It also includes an exhaust pipe (18), which is in communication with the air-sealed cavity (17), and a lower half of the exhaust pipe (18) is provided as an oil drain channel.

6. The bearing oil sealing structure of a sliding bearing according to claim 1, characterized in that: A first sealing packing (3) is arranged on the left side of the bearing housing (4), a first sealing ring (2) is arranged in a centripetal circumferential groove of the first sealing packing (3), a second sealing ring (8) is installed in a centripetal circumferential groove of the second sealing packing (9), a third sealing ring (15) is installed in a centripetal circumferential groove of the third sealing packing (12), and the first sealing packing (3), the second sealing packing (9) and the third sealing packing (12) are concentric.

7. The bearing oil sealing structure of a sliding bearing according to claim 1, characterized in that: The bearing housing (4) is connected to a ventilation pipe (7), and a breathing cap (5) is arranged at the upper end of the ventilation pipe (7).

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