CN210135088U

CN210135088U - Lubricating oil leakage-proof device of air compressor

Info

Publication number: CN210135088U
Application number: CN201920465656.9U
Authority: CN
Inventors: 邢子义; 王升科
Original assignee: Yantai Lingchen Energy Co Ltd
Current assignee: Yantai Dongde Hydrogen Energy Technology Co Ltd
Priority date: 2019-04-04
Filing date: 2019-04-04
Publication date: 2020-03-10
Anticipated expiration: 2029-04-04

Abstract

The utility model relates to an air compressor's lubricating oil prevents leaking device, air compressor's rotor and gear link to each other, and the gear setting is equipped with lubricating oil, a serial communication port in the oil pocket, include: the pressure relief unit comprises an exhaust hole communicated with the oil cavity, a vent valve is arranged at the port of the exhaust hole, and gas in the oil cavity is exhausted by the vent valve; and the lubricating oil circulating unit comprises an oil discharge channel and an oil return channel which are respectively communicated with the oil cavity at a first position and a second position, and the oil discharge channel and the oil return channel are connected through a pipeline. The utility model can quickly release pressure of the oil cavity, is provided with the lubricating fluid circulating channel, and utilizes the internal pressure of the oil cavity to make the lubricating oil flow along the circulation, so that a small amount of lubricating oil in the oil cavity enters the position of the vent valve, thereby effectively reducing the leakage amount of the lubricating oil; and new lubricating oil is not required to be added into the oil cavity frequently, so that the bearing and the gear are always in a good lubricating state.

Description

Lubricating oil leakage-proof device of air compressor

Technical Field

The utility model relates to an air compressor's lubricating oil prevents leaking device.

Background

The rotor of the existing air compressor generally drives a gear to rotate through a motor, the gear needs to be connected with a rotor through a bearing, an air chamber in which the rotor in a shell of the compressor is located needs to be in an oil-free state, therefore, an oil seal needs to be arranged between the bearing and the air chamber to prevent lubricating oil in an oil cavity at the position of the bearing from entering the air chamber, after the rotor rotates and works, compressed air in the air chamber can enter the oil cavity at the position of the bearing along a gap at the position of the oil seal to increase the pressure of the oil cavity, in order to ensure the normal connection state of the bearing and related components, the oil cavity needs to be decompressed, in the prior art, a hole is drilled in the oil cavity and a vent valve is installed, so that high-pressure air in the oil cavity is discharged from the vent valve, but the existing vent valve can entrain the lubricating; in addition, when the pressure in the oil cavity rises, the sealing effect of the traditional oil seal design on lubricating oil cannot meet the use requirement, partial lubricating oil leaks into the air chamber from the oil seal position to influence the air compression of the rotor, and particularly when the air compressor is applied to the field of fuel cells, because the lubricating oil can poison the electric pile of the fuel cells, the air discharged by the air compressor is not allowed to contain the oil, namely the lubricating oil in the oil cavity is prevented from entering the air chamber of the air compressor; lubricating oil still needs regularly to supply after producing the leakage, has increased use cost, and extravagant lubricating oil if can not in time supply lubricating oil can lead to the wearing and tearing of bearing and gear, influences air compressor's work efficiency, reduces equipment life.

SUMMERY OF THE UTILITY MODEL

The utility model provides an air compressor's lubricating oil prevents leaking device, its structural design is reasonable, can carry out quick pressure release to the oil pocket, sets up lubricating fluid circulation channel, utilizes the internal pressure of oil pocket to make lubricating oil along circulation flow, makes a small amount of lubricating oil in the oil pocket get into the breather valve position, has effectively reduced the leakage quantity of lubricating oil; meanwhile, after the vent valve is improved, the oil mist separation function is added, so that the oil mist passing through the vent valve is effectively separated, gas is discharged, lubricating oil is trapped, and the problem of lubricating oil leakage is thoroughly solved; the bearing and the gear are always in a good lubricating state without adding new lubricating oil frequently to the oil cavity, so that the working efficiency of the air compressor is ensured, the failure rate of equipment is reduced, the service life of the equipment is prolonged, and the problems in the prior art are solved.

The utility model discloses a solve the technical scheme that above-mentioned technical problem adopted and be: device is prevented leaking by air compressor's lubricating oil, air compressor's rotor and gear link to each other, the gear setting is in the oil pocket, be equipped with lubricating oil in the oil pocket, include:

the pressure relief unit comprises an exhaust hole communicated with the oil cavity, and a vent valve is arranged at the port of the exhaust hole and used for exhausting gas in the oil cavity;

the lubricating oil circulating unit comprises an oil discharge channel and an oil return channel which are respectively communicated with the oil cavity at a first position and a second position, and the oil discharge channel and the oil return channel are connected through a pipeline; the oil return channel comprises a first section and a second section, the first section is connected with the exhaust hole, an oil-gas separation unit is arranged in the first section and comprises an oil mist inlet, a gas outlet and a liquid outlet, the oil mist inlet is communicated with the pipeline correspondingly, the gas outlet is communicated with the exhaust hole, the liquid outlet is communicated with the second section correspondingly, and the second section is communicated with the inside of the oil cavity.

Further, the oil discharge channel is arranged below the oil cavity and communicated with the oil cavity; the oil-gas separation unit is positioned above the oil cavity and correspondingly communicated with the second section, and the second section is communicated with the oil cavity.

Further, the first section setting of oil return passageway is in the top of oil pocket, the second section with be equipped with between the oil pocket and get rid of oily circulation passageway, get rid of oily circulation passageway including first horizontal hole and the second horizontal hole of the different positions of intercommunication oil pocket, first horizontal hole is linked together with the different positions of second section with the second horizontal hole respectively, the axis of first horizontal hole roughly with the bottom of gear in the oil pocket is tangent to be set up, the axis of second horizontal hole roughly with the top of gear in the oil pocket is tangent to be set up.

Furthermore, an oil mist inlet of the oil mist separation unit is provided with an oil return valve body, a through hole of the oil return valve body is connected with the filter core body, and the filter core body is respectively arranged corresponding to the gas outlet and the liquid outlet of the oil mist separation unit.

Further, the exhaust hole is arranged above the oil cavity, and the axis of the exhaust hole is generally tangent to the side face of the gear in the oil cavity.

Furthermore, a lubricating oil interception unit is arranged in the vent valve, and only the air in the oil cavity is discharged outwards by the lubricating oil interception unit.

Further, the breather valve includes the breather valve body, be equipped with the case of ventilating in the breather valve body, it intercepts the chamber to be equipped with between case of ventilating and the valve cap of ventilating, it is equipped with to intercept the intracavity the unit is held back to lubricating oil, lubricating oil is held back the unit and is included the filter core of ventilating, the filter core of ventilating is less than the minimum clearance size that lubricating oil can pass through with the clearance of holding back intracavity wall contact position.

Furthermore, one side of the ventilating filter element is connected with the ventilating valve cap through a spring and can slide along the inner wall of the interception cavity.

Furthermore, be equipped with the first sealing member of isolation air compressor air chamber in the bearing end cover, first sealing member with be equipped with the second sealing member between the bearing, first sealing member with be formed with the oil impregnate groove between the second sealing member, oil drain channel sets up the oil impregnate groove position.

Further, the circumferential surface of the first sealing element is provided with a reverse spiral structure, and the thread direction of the reverse spiral structure is opposite to the rotation direction of the first sealing element.

The structure adopted by the utility model has the advantages that the structure design is reasonable, the oil cavity can be quickly decompressed, the lubricating liquid circulating channel is arranged, the lubricating oil circularly flows by utilizing the internal pressure of the oil cavity, a small amount of lubricating oil in the oil cavity enters the position of the vent valve, and the leakage amount of the lubricating oil is effectively reduced; meanwhile, after the vent valve is improved, the oil mist separation function is added, so that the oil mist passing through the vent valve is effectively separated, gas is discharged, lubricating oil is trapped, and the problem of lubricating oil leakage is thoroughly solved; new lubricating oil does not need to be added into the oil cavity frequently, so that the bearing and the gear are always in a good lubricating state, the working efficiency of the air compressor is ensured, the failure rate of equipment is reduced, and the service life of the equipment is prolonged.

Drawings

Fig. 1 is a schematic perspective view of the present invention;

FIG. 2 is a schematic side view of the present invention;

FIG. 3 is a schematic view of the present invention in a partial cross-sectional structure;

FIG. 4 is a schematic sectional view of the portion A-A in FIG. 2;

fig. 5 is a schematic structural view of the vent valve of the present invention;

fig. 6 is a schematic structural diagram of the oil-gas separation unit of the present invention.

In the figure, 1, a bearing end cover; 2. an oil chamber; 3. a bearing; 4. an air compressor; 5. a rotor; 6. a rotating shaft; 7. a gear; 8. a motor; 9. an exhaust hole; 10. a vent valve; 11. an air chamber; 12. an oil discharge passage; 13. a pipeline; 14. an oil return passage; 1401. a first stage; 1402. a second stage; 15. an oil-gas separation unit; 1501. an oil return valve body; 1502. a filter element body; 1503. a through hole; 16. an oil throwing circulation channel; 1601. A first horizontal hole; 1602. a second horizontal hole; 17. a lubricating oil retention unit; 1701. a ventilation filter element; 1702. a spring; 18. a vent valve body; 19. a vent valve core; 20. a vented bonnet; 21. a trapping cavity; 22. A first seal member; 23. a second seal member; 24. an oil seepage groove; 25. a first composite washer; 26. an O-shaped ring; 27. a second composite washer; 28. a connecting head.

Detailed Description

In order to clearly illustrate the technical features of the present invention, the present invention is explained in detail by the following embodiments in combination with the accompanying drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, however, the present application may be practiced in other ways than those described herein, and therefore the scope of the present application is not limited by the specific embodiments disclosed below.

In addition, in the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like, indicate orientations and positional relationships based on those shown in the drawings, are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; the connection can be mechanical connection, electrical connection or communication; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. In the description herein, reference to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

As shown in fig. 1-6, in the lubricating oil leakage preventing device of the air compressor, a rotor 5 of the air compressor 4 is connected with a gear 7, the gear 7 is arranged in an oil cavity 2, lubricating oil is arranged in the oil cavity 2, specifically, a bearing end cover 1 is arranged outside the oil cavity 2, a bearing 3 is arranged in the bearing end cover 1, the bearing 3 is connected with a rotating shaft 6 supporting the rotor 5 of the air compressor 4, the rotating shaft 6 of the rotor 5 of the air compressor 4 is connected with the gear 7 through the bearing 3, and the gear 7 is connected with an output shaft of a motor 8; rotor 5 of air compressor 4 starts rotation work under motor 8 and gear 7 drive, and the air admission oil pocket 2 in the air chamber 11, too much back pressure rising is accumulated to air in the oil pocket 2, and the lubricating oil that oppresses in the oil pocket 2 circulates along the circulation of lubricating oil circulation unit flow, and the concrete flow path of lubricating oil is: after the lubricating oil in the oil chamber 2 flows back to the oil return channel 14 from the oil discharge channel 12 through the pipeline 13, the lubricating oil firstly enters the oil mist separation unit 15 from the oil mist inlet of the oil-gas separation unit 15, the lubricating oil is filtered and separated by the oil mist separation unit 15, the separated gas is discharged from the gas outlet of the oil mist separation unit 15, flows to the exhaust hole 9 along the first section 1401 of the oil return channel 14 and is discharged from the breather valve 10 through the exhaust hole 9; the separated lubricating oil is discharged from the liquid outlet and returned to the inside of the oil chamber 2 along the second section 1402 of the oil return passage 14. In the working state of the air compressor 4, most of the lubricating oil can flow along the lubricating oil circulation unit, the lubricating oil circulation unit can consume most of high-pressure air in the oil cavity 2, and the air is filtered and separated by the oil-gas separation unit and then is discharged from the vent valve 10; and the residual gas in the oil cavity 2 can be directly exhausted from the vent valve 10 through the vent hole, even if the common vent valve in the prior art is adopted, the residual gas in the oil cavity 2 can only be mixed with a small amount of lubricating oil to be exhausted from the position of the vent valve, so that the leakage amount of the lubricating oil is greatly reduced, and the problem of the lubricating oil leakage of the prior air compressor 4 is effectively controlled.

For a detailed explanation of the oil discharge passage 12 and the oil return passage 14 in the lubricating oil circulating unit, the oil discharge passage 12 is provided below the oil chamber 2 and communicates with the oil chamber 2, and the pressure in the oil chamber 2 plus the self-weight of the lubricating oil causes the lubricating oil to enter the oil discharge passage 12 from the oil chamber 2; the oil-gas separation unit 15 is located above the oil chamber 2 and is correspondingly communicated with the second section 1402, and the second section 1402 is communicated with the oil chamber 2. Specifically, the oil discharge passage 12 is connected to the bottom of the oil chamber 2, the oil return position of the oil return passage 14 is set above the oil chamber 2, and the second section 1402 of the oil return passage 14 is connected to the side of the oil chamber 2, so that the lubricating oil in the oil chamber 2 is discharged from the oil discharge passage 12 and flows back from the second section 1402 of the oil return passage 14.

In addition, it is worth mentioning that the first section 1401 of the oil return channel 14 is arranged substantially horizontally and is communicated with the exhaust hole 9, which is beneficial to the processing design of the first section 1401 and also beneficial to the air separated by the oil-gas separation unit 15 to rapidly flow to the position of the vent valve 10 of the exhaust hole 9.

In consideration of practical processing use, the first section 1401 of the oil return channel 14 is arranged above the oil cavity 2, so that lubricating oil separated by the oil-gas separation unit 15 can drop into the second section 1402 under the action of gravity, and the lubricating oil can return to the inside of the oil cavity 2 more easily; meanwhile, because the second section 1402 of the oil return passage 14 is communicated with the oil chamber 2, the gear 7 in the oil chamber 2 can throw the lubricating oil outwards when rotating at a high speed, the lubricating oil can enter the second section 1402 of the oil return passage 14, the higher the rotating speed of the gear 7 is, the more the amount of the lubricating oil entering the second section 1402 is, the more the amount of the lubricating oil entering the oil chamber is, the oil-gas separation unit 15 can be soaked when the amount of the lubricating oil entering the oil chamber is too much, the effect of the oil-gas separation unit 15 is affected, the oil-gas separation unit 15 can be damaged by long-time soaking, in order to effectively protect the oil-gas separation unit 15 and avoid the soaking of the lubricating oil, in the scheme, the oil throwing circulation passage 16 is arranged between the second section and the oil chamber, the oil throwing circulation passage 16 comprises a first horizontal hole 1601 and a second horizontal hole 1602 which are communicated with different positions of the oil chamber 2, the first horizontal hole 1601 and the second horizontal hole 1602 are respectively, the axis of the second horizontal hole 1602 is generally tangent to the top of the gear 7 in the oil chamber 2, and after the gear 7 rotates, the lubricating oil thrown outwards can enter the first horizontal hole 1601 and then pass through the second section 1402, and due to the action of centrifugal force, the lubricating oil in the second section 1402 can be thrown back to the oil chamber 2 again along the second horizontal hole 1602, so that the lubricating oil is prevented from soaking the oil-gas separation unit 15 through the second section 1402.

Specifically, an oil mist inlet of the oil mist separation unit 15 is provided with an oil return valve body 1501, a through hole 1503 of the oil return valve body 1501 is connected with a filter core body 1502, the filter core body 1502 is respectively arranged corresponding to a gas outlet and a liquid outlet of the oil mist separation unit 15, so that separated air enters the first section 1401, and lubricating oil filtered by the filter core body 1502 enters the second section 1402 and flows back to the oil chamber 2 again along the second section 1402.

During actual processing and installation, as shown in fig. 4, the oil outlet of the oil discharge channel 12 is provided with a connector 28, and a detachably connected pipeline 13 is arranged between the connector 28 and the oil return valve body 1501, so that the oil discharge channel is convenient to install and use in a matching manner.

The exhaust hole 9 is arranged above the oil cavity 2, the axis of the exhaust hole is generally tangent to the side face of the gear 7 in the oil cavity 2, the exhaust hole is generally arranged in the vertical direction and can be tangent to the tooth surface of the gear 7, and air mixed with lubricating oil can smoothly enter the exhaust hole 9 and is timely decompressed when the gear 7 rotates at a high speed.

In order to thoroughly solve the problem of leakage of lubricating oil, a lubricating oil interception unit 17 is arranged in a breather valve 10, the lubricating oil interception unit 17 only enables air in an oil cavity 2 to be discharged outwards, a small amount of lubricating oil directly entering an exhaust hole 9 from the oil cavity 2 is filtered and intercepted by the lubricating oil interception unit, no leakage of the lubricating oil at the position of the breather valve 10 is ensured, most of the lubricating oil flows through a lubricating oil circulation unit, and only a small amount of lubricating oil is mixed with the air and passes through the breather valve 10, so the lubricating oil can be effectively filtered by the lubricating oil interception unit 17, but if the lubricating oil circulation unit is not shared and matched, if the filtering unit is directly added at the position of the breather valve in the prior art, a large amount of oil mist can rapidly damage the filtering unit, the normal service life cannot be ensured, and the lubricating oil can be replaced reversely frequently, so, the scheme just solves the problem and thoroughly solves the leakage of the lubricating oil.

For further details of the vent valve 10 and the lubricant retaining unit 17, the vent valve 10 includes a vent valve body 18, a vent valve core 19 is disposed in the vent valve body 18, a retaining cavity 21 is disposed between the vent valve core 19 and a vent valve cap 20, the lubricant retaining unit 17 is disposed in the retaining cavity 21, the lubricant retaining unit 17 includes a vent filter core 1701, a gap between the vent filter core 1701 and an inner wall of the retaining cavity 21 is smaller than a minimum gap size through which lubricant can pass, oil mist entering the vent valve 10 first passes through the vent valve core 19, the vent valve core 19 can play a certain buffering and scattering role on the oil mist, so that lubricant oil trapped in air can better contact with the vent filter core 1701, the lubricant oil is filtered and retained by the vent filter core 1701, and air passes through the vent filter core 1701.

As shown in fig. 5, in order to effectively filter and separate the oil mist which impacts into the breather valve 10, one side of the breather filter core 1701 is connected with the breather valve cap 20 through the spring 1702 and can slide along the inner wall of the interception cavity 21, when the oil mist which moves at a high speed passes through the breather valve core 19 of the breather valve 10, the breather filter core 1701 can impact and slide along the interception cavity 21, the spring 1702 connected with the breather filter core 1701 is squeezed, the breather filter core 1701 can repeatedly move along the interception cavity 21 under the dual actions of the impact of the high-pressure oil mist and the elastic force of the spring 1702, the impact damage of the oil mist to the breather filter core 1701 is effectively reduced, the service life of the breather filter core 1701 is prolonged, and the oil mist filtering.

In view of the functional requirements of the filter core 1502 and the breather filter element 1701, sintered filter elements of different configurations and shapes may be specifically selected for the filter core 1502 and the breather filter element 1701. The sintered filter element has good filtering performance; the shape is stable, and the element has higher strength; high temperature resistance; the corrosion resistance is strong; impact resistance and high alternating load; good air permeability and separation effect.

As shown in fig. 3, a first sealing member 22 for isolating an air chamber 11 of the air compressor 4 is arranged in the bearing end cover 1, a second sealing member 23 is arranged between the first sealing member 22 and the bearing 3, an oil-permeable groove 24 is formed between the first sealing member 22 and the second sealing member 23, the oil discharge passage 12 is arranged at the oil-permeable groove 24, the lubricating oil in the oil chamber 2 leaks into the oil-permeable groove 24 along the second sealing member 23, and when the air compressor 4 works, the air enters the oil-permeable groove 24 from a gap of the first sealing member 22, and the lubricating oil in the oil-permeable groove 24 is extruded into the oil discharge passage 12.

The circumferential surface of the first sealing member 22 is provided with a reverse spiral structure having a thread direction opposite to the rotation direction of the first sealing member 22. When the first sealing member 22 rotates along with the rotor 5, the reverse thread structure of the surface of the first sealing member rotates to limit the lubricating oil in the oil chamber 2 from entering the air chamber 11 along the gap between the first sealing member 22 and the bearing end cover 1.

It is worth mentioning that in the specific mounting assembly, the first seal 22 comprises a mechanical seal and the second seal 23 comprises a rotary oil seal.

As shown in fig. 5 and 6, in order to maintain good tightness between the vent valve 10 and the vent hole 9, a first combined gasket 25 is arranged at the inlet position of the vent valve body 18 and the vent hole 9, and an O-ring 26 is arranged between the vent valve body 18 and the inner wall of the vent hole 9; the oil return valve body 1501 and the inlet position of the oil return passage 14 are provided with a second combination washer 27.

The above-mentioned specific embodiments can not be regarded as the restriction to the scope of protection of the utility model, to technical personnel in this technical field, it is right the utility model discloses any replacement improvement or transform that embodiment made all fall within the scope of protection of the utility model.

The parts of the present invention not described in detail are the known techniques of those skilled in the art.

Claims

1. Air compressor's lubricating oil leakage preventing device, air compressor's rotor and gear link to each other, the gear setting is in the oil pocket, be equipped with lubricating oil in the oil pocket, its characterized in that includes:

2. A lubricating oil leakage preventing device for an air compressor, as claimed in claim 1, wherein said oil drain passage is provided below said oil chamber and communicates with said oil chamber; the oil-gas separation unit is positioned above the oil cavity and correspondingly communicated with the second section, and the second section is communicated with the oil cavity.

3. The apparatus of claim 2, wherein the first section of the oil return passage is disposed above the oil chamber, and a slinging circulation passage is disposed between the second section and the oil chamber, the slinging circulation passage includes a first horizontal hole and a second horizontal hole communicating different positions of the oil chamber, the first horizontal hole and the second horizontal hole are respectively communicated with different positions of the second section, an axis of the first horizontal hole is substantially tangential to a bottom of the gear in the oil chamber, and an axis of the second horizontal hole is substantially tangential to a top of the gear in the oil chamber.

4. A lubricant leakage preventing device for an air compressor, according to claim 3, wherein a return valve body is provided at a position of an oil mist inlet of said oil-gas separation unit, a through hole of said return valve body is connected to a filter element body, and said filter element body is provided corresponding to a gas outlet and a liquid outlet of said oil-gas separation unit, respectively.

5. A leakage preventing device for lubricating oil of air compressor as claimed in any one of claims 1 to 4, wherein said air discharge hole is provided above said oil chamber with its axis being substantially tangential to the side of the gear in said oil chamber.

6. A leakage preventing device for lubricating oil of air compressor, according to claim 5, wherein a lubricating oil intercepting unit is provided in said breather valve, said lubricating oil intercepting unit discharging only air inside the oil chamber to the outside.

7. A lubricating oil leakage preventing device for an air compressor, according to claim 6, wherein said vent valve includes a vent valve body, a vent valve core is disposed in said vent valve body, a trapping cavity is disposed between said vent valve core and said vent valve cap, said trapping cavity is disposed with said lubricating oil trapping unit, said lubricating oil trapping unit includes a vent filter core, and a gap between contact positions of said vent filter core and inner wall of said trapping cavity is smaller than a minimum gap size through which lubricating oil can pass.

8. An apparatus for preventing leakage of lubricating oil for an air compressor as claimed in claim 7, wherein said breather filter is connected at one side thereof to a breather valve cap via a spring and slidable along an inner wall of said trap chamber.

9. A leakage preventing device for lubricating oil of an air compressor, according to claim 7 or 8, wherein said oil chamber includes a bearing end cover outside, a bearing is installed in said bearing end cover, said bearing is connected to a rotor supporting said air compressor, a first sealing member for isolating an air chamber of said air compressor is installed in said bearing end cover, a second sealing member is installed between said first sealing member and said bearing, an oil leakage groove is formed between said first sealing member and said second sealing member, and said oil discharge channel is installed at said oil leakage groove.

10. A leakage preventing device for lubricating oil of an air compressor, according to claim 9, wherein a circumferential surface of said first sealing member is provided with a reverse spiral structure, a thread direction of said reverse spiral structure being opposite to a rotation direction of said first sealing member.