External pressure balancing end cover system of air compressor

Abstract

The utility model relates to the technical field of air compressors. An air compressor external pressure balance end cover system comprises an end cover, the end cover is provided with a shaft hole, and a labyrinth structure is arranged in the shaft hole. The shaft hole is formed in the outer side of the labyrinth structure, and an annular cavity is further formed in the inner wall of the shaft hole; the annular cavity is provided with an air inlet hole which is communicated with the air outlet through a pipeline. After compressed air is introduced from the air outlet, mutually balanced pressure is formed on the two sides of the labyrinth structure of the shaft hole, and then the problem that lubricating oil leaks when the lubricating oil passes through a gap between the shaft hole and the rotating shaft due to the fact that the pressure on the main machine side of the air compressor is too large is solved.

Description

Technical Field

[0001] The present application relates to the field of air compressors, and in particular to an oil seal assembly device. Background Art

[0002] In the traditional air compressor structure design, an oil seal is set on the screw shaft to isolate the main engine and the motor to prevent the lubricating oil from flowing out from the main engine side. However, there is a high pressure on the main engine side of the air compressor, which leads to the limited effect of the oil seal. The lubricating oil on the main engine side often leaks under the action of pressure. In order to reduce the loss of lubricating oil and improve production efficiency and quality, it is necessary to provide an efficient and reliable end cover system with oil sealing effect. Utility Model Content

[0003] The utility model aims to provide an air compressor external pressure balance end cover system to solve at least one of the above technical problems.

[0004] The technical problem solved by the present invention can be achieved by adopting the following technical solutions:

[0005] An air compressor external pressure balance end cover system comprises an end cover, wherein the end cover has an axial hole, and a labyrinth structure is arranged in the axial hole;

[0006] The axial hole is outside the labyrinth structure, and an annular cavity is arranged on the inner wall of the axial hole;

[0007] The annular cavity is provided with an air inlet hole, which is connected to the high-pressure air outlet of the air compressor through a pipeline;

[0008] Outside the annular cavity, another labyrinth structure is provided in the shaft hole;

[0009] A labyrinth shaft seal matching structure engaged with the two labyrinth structures is arranged on the rotating shaft inserted into the shaft hole.

[0010] In this design, a labyrinth seal structure is set in the shaft hole. The labyrinth seal structure forms a series of interception gaps and expansion cavities between the sealing teeth. The lubricating oil in the air compressor produces an interception effect when passing through the gaps of the tortuous labyrinth, thereby achieving the purpose of preventing the leakage of the lubricating oil.

[0011] Behind the labyrinth sealing structure, there is an annular cavity for introducing external compressed gas. The compressed gas comes from the air outlet of the air compressor. The pressure of the air outlet of the air compressor and the pressure in the main chamber of the air compressor are the same. Therefore, after the compressed air is introduced into the annular cavity from the air outlet, mutually balanced pressures are formed on both sides of the labyrinth structure of the shaft hole, thereby eliminating the problem of excessive pressure on the main engine side of the air compressor causing the lubricating oil to leak through the gap between the shaft hole and the rotating shaft.

[0012] The purpose of setting another labyrinth structure in the shaft hole outside the annular cavity is to prevent the compressed gas from escaping through the gap between the shaft hole of the end cover and the rotating shaft, thereby reducing the production efficiency of the air compressor.

[0013] Furthermore, the labyrinth seal structure on the shaft seal is provided with at least two annular sealing teeth, the cross section of the sealing teeth is either a triangle or a trapezoid, and the interval between each sealing tooth is 5 to 10 mm.

[0014] The mechanism of the labyrinth seal is that the lubricating oil produces a throttling effect when passing through the interception gap and the expansion cavity, thereby achieving the purpose of preventing leakage. Therefore, it is necessary to set up multiple annular sealing teeth to form the interception gap and the expansion cavity. The cross-section of the sealing teeth adopts a trapezoidal or triangular shape. Its purpose is also to form the effect of the expansion cavity and play an intercepting effect on the leakage of the lubricating oil.

[0015] Furthermore, the annular cavity is a cutting groove with a rectangular cross section; the outer diameter of the cutting groove of the annular cavity is larger than the outer diameter of the labyrinth sealing structure.

[0016] The annular cavity adopts a rectangular cutting groove, which is convenient for processing and can reduce the cost of production. The outer diameter of the annular cavity cutting groove is larger than the outer diameter of the labyrinth sealing structure, forming a larger storage space for introducing external compressed gas to offset the pressure in the main engine on the other side of the labyrinth sealing structure.

[0017] Furthermore, a heat exchanger is arranged on the pipeline.

[0018] After the air compressor compresses the air, the compressed gas will cause its temperature to rise. If the heated compressed gas is used directly, the viscosity of the lubricating oil will decrease, affecting the oil sealing effect. Therefore, before introducing the compressed gas, a heat exchanger needs to be set up to cool the compressed gas.

[0019] Furthermore, outside the annular cavity, another annular cavity is arranged in the shaft hole, and the annular cavity is provided with an oil inlet hole, which is connected to the oil supply control system through an oil passage. The annular cavity is called an oil storage cavity.

[0020] The role of the annular cavity in introducing compressed gas from the air outlet is to form a pressure balance on both sides of the shaft hole maze structure to prevent the lubricating oil from leaking through the gap between the shaft hole and the rotating shaft due to excessive pressure on the main engine side. However, while the annular cavity balances the pressure on the main engine side, it will also leak through the gap between the shaft hole and the rotating shaft. In the case of severe leakage, it will cause the loss of compressed gas and reduce production efficiency. In order to solve this problem, an oil storage chamber is set behind the annular cavity, which provides a sealing oil film for the maze structure to prevent the escape of compressed gas in the annular cavity.

[0021] Further optimization also includes an oil supply control system for providing oil supply; the oil supply control system includes an oil supply pump, the oil inlet pipeline of the oil supply pump is connected to the oil storage tank in the air compressor, and the oil outlet pipeline of the oil supply pump is connected to the oil channel of the oil storage chamber.

[0022] In the utility model, the oil supply control system supplies sealing oil to the oil storage cavity through the oil supply pump, which prevents the compressed gas in the annular cavity from escaping and losing, thereby improving the production efficiency of compressed gas in the air compressor.

[0023] The utility model provides a labyrinth seal structure on the shaft hole of the end cover, and prevents lubricating oil leakage by the intercepting effect of the labyrinth seal. Compressed gas introduced from the air outlet of the air compressor is provided at the rear of the labyrinth seal structure to balance the internal pressure on the main engine side, thereby eliminating the problem of easy leakage of lubricating oil caused by excessive air pressure on the main engine side, reducing the problem of lubricating oil consumption caused by leakage, saving production costs, and improving production efficiency.

[0024] Its beneficial effect is that after solving the problem of lubricating oil leakage, an oil storage chamber and a labyrinth sealing structure are provided behind the annular cavity to strengthen the protection against the escape and loss of compressed gas, thereby preventing the escape and loss of compressed gas in the annular cavity and improving the production efficiency of compressed gas in the air compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following briefly introduces the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0026] Figure 1 It is a schematic diagram of the utility model;

[0027] Figure 2 It is a cross-sectional view of the utility model.

[0028] Explanation of symbols:

[0029] 1. End cover; 3. Shaft hole; 4. Sealing tooth; 6. Annular cavity; 7. Oil inlet hole; 8. Oil storage cavity; 9. Air inlet hole. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned purposes, features and advantages of the present invention more understandable, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general proportion, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0033] Secondly, the "one embodiment" or "embodiment" referred to herein refers to a specific feature, structure or characteristic that can be included in at least one implementation of the utility model. The "in one embodiment" that appears in different places in this specification does not refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0034] Reference Figure 1 , Figure 2 As shown, the air compressor external pressure balance end cover system includes an end cover 1, the end cover 1 has an axial hole 3, and a labyrinth structure is arranged in the axial hole 3;

[0035] The shaft hole 3 is outside the labyrinth structure, and an annular cavity 6 is provided on the inner wall of the shaft hole 3;

[0036] The annular cavity 6 is provided with an air inlet 9, and the air inlet 9 is connected to the high-pressure air outlet of the air compressor through a pipeline;

[0037] Outside the annular cavity 6, another labyrinth structure is provided in the shaft hole 3;

[0038] The rotating shaft inserted into the shaft hole 3 is provided with a labyrinth shaft seal matching structure which engages with the two labyrinth structures.

[0039] In this design, a labyrinth seal structure is set in the shaft hole 3. The labyrinth seal structure forms a series of interception gaps and expansion cavities between the sealing teeth 4. The lubricating oil in the air compressor produces an interception effect when passing through the gaps of the tortuous labyrinth, thereby achieving the purpose of preventing the leakage of the lubricating oil.

[0040] In this embodiment, an annular cavity 6 for introducing external compressed gas is provided behind the labyrinth sealing structure. The compressed gas comes from the air outlet of the air compressor. The pressure at the air outlet of the air compressor and the pressure in the main cavity of the air compressor are of the same origin. Therefore, after the annular cavity 6 introduces compressed air from the air outlet, mutually balanced pressures are formed on both sides of the labyrinth structure of the shaft hole, thereby eliminating the problem of excessive pressure on the main body side of the air compressor causing the lubricating oil to leak through the gap between the shaft hole and the rotating shaft.

[0041] In another embodiment, the compressed gas may also be high-pressure gas from the main chamber of the air compressor.

[0042] In this embodiment, another labyrinth structure is provided in the shaft hole 3 outside the annular cavity 6 to prevent the compressed gas from escaping through the gap between the shaft hole 3 of the end cover 1 and the rotating shaft, thereby reducing the production efficiency of the air compressor.

[0043] The labyrinth seal structure on the shaft seal is provided with at least two annular sealing teeth 4, the cross section of the sealing teeth 4 is either a triangle or a trapezoid, and each sealing tooth 4 is spaced 5 to 10 mm apart.

[0044] The mechanism of the labyrinth seal is that the lubricating oil produces a throttling effect when passing through the interception gap and the expansion cavity, thereby achieving the purpose of preventing leakage. Therefore, it is necessary to set a plurality of annular sealing teeth 4 to form the interception gap and the expansion cavity. The cross-section of the sealing teeth 4 is trapezoidal or triangular, and its purpose is also to form the effect of the expansion cavity, thereby intercepting the leakage of the lubricating oil.

[0045] The annular cavity 6 is a cutting groove with a rectangular cross section; the outer diameter of the cutting groove of the annular cavity 6 is larger than the outer diameter of the labyrinth sealing structure.

[0046] In this embodiment, the annular cavity 6 adopts a rectangular cutting groove, which is convenient for processing and can reduce the cost of production. The outer diameter of the cutting groove of the annular cavity 6 is larger than the outer diameter of the labyrinth sealing structure, forming a larger storage space for introducing external compressed gas to offset the pressure in the main engine on the other side of the labyrinth sealing structure.

[0047] A heat exchanger is arranged on the pipeline.

[0048] In this embodiment, after the air compressor compresses the air, the compressed gas will cause the temperature to rise. If the heated compressed gas is used directly, the viscosity of the lubricating oil will decrease, affecting the oil sealing effect. Therefore, before introducing the compressed gas, a heat exchanger needs to be set to cool the compressed gas.

[0049] Heat exchangers are existing technologies, and the heat exchangers that can be used include tube-row heat exchangers or plate heat exchangers.

[0050] Outside the annular cavity 6, another annular cavity 6 is arranged in the shaft hole 3. The annular cavity 6 is provided with an oil inlet hole 7. The oil inlet hole 7 is connected to the oil supply control system through an oil passage. The annular cavity 6 is called an oil storage cavity 8.

[0051] In this embodiment, the annular cavity 6 introduces compressed gas from the gas outlet to form a pressure balance on both sides of the labyrinth structure of the shaft hole 3, thereby preventing the lubricating oil from leaking through the gap between the shaft hole 3 and the rotating shaft due to excessive pressure on the main engine side. However, while balancing the pressure on the main engine side, the annular cavity 6 itself may leak through the gap between the shaft hole 3 and the rotating shaft. In the case of severe leakage, it will cause the loss of compressed gas and reduce production efficiency. In order to solve this problem, an oil storage cavity 8 is set behind the annular cavity 6, and the oil storage cavity 8 provides a sealing oil film for the labyrinth structure to prevent the escape of compressed gas in the annular cavity 6.

[0052] It also includes an oil supply control system for providing oil; the oil supply control system includes an oil supply pump, the oil inlet pipeline of the oil supply pump is connected to the oil storage tank in the air compressor, and the oil outlet pipeline of the oil supply pump is connected to the oil channel of the oil storage chamber 8.

[0053] In this embodiment, the oil supply control system supplies sealing oil to the oil storage chamber 8 through an oil supply pump, which prevents the compressed gas in the annular cavity 6 from escaping and being lost, thereby improving the production efficiency of compressed gas in the air compressor.

[0054] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment may not be described, ie, those features that are not relevant to the best mode of the invention or those features that are not relevant to implementing the invention.

[0055] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, the development effort will be a routine task of design, fabrication, and production without undue experimentation.

[0056] It should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. An air compressor external pressure balance end cover system comprises an end cover having an axial hole, characterized in that: A maze structure is arranged in the shaft hole; The axial hole is outside the labyrinth structure, and an annular cavity is arranged on the inner wall of the axial hole; The annular cavity is provided with an air inlet hole, which is connected to the high-pressure air outlet of the air compressor through a pipeline; Outside the annular cavity, another labyrinth structure is provided in the shaft hole; A labyrinth shaft seal matching structure engaged with the two labyrinth structures is arranged on the rotating shaft inserted into the shaft hole.

2. The air compressor external pressure balance end cover system according to claim 1, characterized in that: The labyrinth seal structure on the shaft seal is provided with at least two annular sealing teeth, the cross section of the sealing teeth is either a triangle or a trapezoid, and the interval between each sealing tooth is 5 to 10 mm.

3. The air compressor external pressure balance end cover system according to claim 1, characterized in that: The annular cavity is a cutting groove with a rectangular cross section; The outer diameter of the cutting groove of the annular cavity is larger than the outer diameter of the labyrinth seal structure.

4. The air compressor external pressure balance end cover system according to claim 1, characterized in that: A heat exchanger is arranged on the pipeline.

5. The air compressor external pressure balance end cover system according to claim 1, characterized in that: Another annular cavity is arranged outside the annular cavity in the shaft hole. The annular cavity is provided with an oil inlet hole, which is connected to the oil supply control system through an oil passage. The annular cavity is called an oil storage cavity.

6. The air compressor external pressure balance end cover system according to claim 5, characterized in that: Also included is an oil supply control system for providing oil supply; The oil supply control system comprises an oil supply pump, an oil inlet pipeline of the oil supply pump is connected to the oil storage tank in the air compressor, and an oil outlet pipeline of the oil supply pump is connected to the oil passage of the oil storage cavity.

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