A screw air compressor and its oil seal device

Abstract

The present invention relates to the field of air compressors, in particular to a screw air compressor and its oil seal device, which includes an air compressor housing, a male rotor, a bearing, an oil seal and an oil seal end cover; one end of the male rotor is provided with a shaft protrusion, the shaft protrusion extends to the outside of the air compressor housing, the shaft protrusion is coated with an oil seal, an oil seal end cover is arranged outside the oil seal, a first oil passage is arranged at the lower part of the oil seal end cover, a second oil passage is arranged between the male rotor seat and the female rotor seat, and the second oil inlet is communicated with the first oil outlet; the second oil outlet of the second oil passage is located inside the female rotor seat; a third oil passage is arranged at the lower part of the female rotor seat, the third oil inlet of the third oil passage is located inside the female rotor seat, and the third oil outlet of the third oil passage is located at the lower part of the air compressor housing. In this patent, even if the oil seal is worn, the lubricating oil can finally return to the inside of the air compressor housing through the first oil passage, the second oil passage, the third oil passage and the oil return pipe, preventing oil leakage.

Description

Technical Field

[0001] The present invention relates to the field of air compressors, and in particular to a screw air compressor and its oil seal device. Background Art

[0002] A traditional air compressor is provided with an oil seal on the crankshaft. The main engine and the motor are separated by the oil seal to prevent lubricating oil from flowing out of the main engine side. If the oil seal is damaged, the sealing will fail, and the lubricating oil in the main engine will flow outside the main engine, resulting in the scrapping of the air compressor. Therefore, it is necessary to perform corresponding treatment on the lubricating oil flowing to the outside of the oil seal. Summary of the Invention

[0003] To solve the above problems, the purpose of the present invention is to provide a screw air compressor and its oil seal device, in which an oil passage for collecting leaked lubricating oil is provided outside the oil seal to prevent the leaked lubricating oil from flowing outside the main engine.

[0004] To achieve the purpose of the present invention, the following technical solutions are adopted for implementation:

[0005] An oil seal device for a screw compressor includes an air compressor housing, a male rotor, a bearing, an oil seal, and an oil seal end cover;

[0006] The air compressor housing is provided with a male rotor seat and a female rotor seat, and the male rotor seat is located above the female rotor seat; the male rotor is rotatably arranged on the male rotor seat through a bearing, one end of the male rotor is provided with a shaft protrusion, the shaft protrusion extends to the outside of the air compressor housing, an oil seal is covered on the shaft protrusion, and the oil seal is located outside the bearing. An oil seal end cover is arranged outside the oil seal, and the oil seal end cover is fixedly arranged on the side surface of the air compressor housing; a limiting flange is arranged on the oil seal end cover, the oil seal is located inside the limiting flange, and the oil seal is limited by the limiting flange;

[0007] A first oil passage is arranged at the lower part of the oil seal end cover, a first oil inlet of the first oil passage is located on the upper end surface of the limiting flange, and a first oil outlet of the first oil passage is located on the side surface of the oil seal end cover connected to the air compressor housing;

[0008] A second oil passage is arranged between the male rotor seat and the female rotor seat, a second oil inlet of the second oil passage is located on the side surface of the air compressor housing, and the second oil inlet is communicated with the first oil outlet; a second oil outlet of the second oil passage is located inside the female rotor seat;

[0009] The female rotor seat is sealed by a female rotor end cover; a third oil passage is arranged at the lower part of the female rotor seat, a third oil inlet of the third oil passage is located inside the female rotor seat, and a third oil outlet of the third oil passage is located at the lower part of the air compressor housing.

[0010] Preferably, an air intake seat is further arranged on the air compressor housing, and the third oil outlet is connected to the air inlet of the air intake seat through an oil return pipe.

[0011] Preferably, a shaft sleeve is provided between the oil seal and the shaft projection, and the shaft sleeve and the bearing are separated by a spacer sleeve; a dust seal is also provided between the outer end of the oil seal end cover and the shaft projection.

[0012] Preferably, an installation portion matching the inner diameter of the male rotor seat is provided on the inner side of the oil seal end cover.

[0013] Preferably, a first opening is further provided on the first oil passage, the first opening is located at the bottom of the oil seal end cover, and a first plug is provided on the first opening.

[0014] Preferably, a second opening is further provided on the third oil passage, the second opening is located on the side surface of the air compressor housing, and a second plug is provided on the second opening.

[0015] Preferably, a fourth oil passage is provided at the lower part of the oil seal end cover. The fourth oil inlet of the fourth oil passage is located at the inner lower side of the oil seal end cover and inside the limiting flange, and the fourth oil outlet of the fourth oil passage is located on the end surface inside the oil seal end cover; a fifth oil passage is provided on the air compressor housing, the fifth oil inlet of the fifth oil passage is communicated with the fourth oil outlet, and the fifth oil outlet of the fifth oil passage is communicated with the compression chamber inside the air compressor housing.

[0016] Preferably, the male rotor seat is provided with a bearing seat, and a sixth oil passage communicating with the compression chamber inside the air compressor housing is provided on the bearing seat.

[0017] Preferably, a throttling hole is provided on the upper inner side of the oil seal end cover, and the outer diameter of the throttling hole is smaller than the inner diameter; the throttling hole is located inside the oil seal.

[0018] A screw air compressor, which adopts the above-mentioned oil seal device.

[0019] In summary, the advantage of the present invention is that even if the oil seal is worn, the lubricating oil can finally return to the inside of the air compressor housing through the first oil passage, the second oil passage, the third oil passage and the oil return pipe, preventing oil leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of a screw air compressor.

[0021] Figure 2 It is a sectional view of the screw air compressor after removing the motor part.

[0022] Figure 3 It is Figure 2 The partial enlarged view in

[0023] Figure 4 And Figure 5 It is a schematic structural diagram of the oil seal end cover.

[0024] Figure 6 And Figure 7It is a schematic structural diagram of an air compressor housing. Detailed implementation

[0025] As Figures 1 to 7 shown, an oil seal device for a screw compressor includes an air compressor housing 1, a male rotor 2, a bearing 3, an oil seal 4, and an oil seal end cover 5.

[0026] As Figure 2 shown, the air compressor housing 1 is provided with a male rotor seat 11 and a female rotor seat 12. The male rotor seat 11 is located above the female rotor seat 12. The male rotor 2 and the female rotor are respectively rotatably arranged on the male rotor seat 11 and the female rotor seat 12 through bearings 3, and the male rotor 2 and the female rotor are meshed with each other. The male rotor seat 11 is provided with a bearing seat 111, and a sixth oil passage 1111 communicating with the compression chamber inside the air compressor housing 1 is arranged on the bearing seat 111. The sixth oil passage 1111 is used to lead the lubricating oil inside the air compressor housing 1 to the bearing 3 to lubricate and cool the bearing 3.

[0027] As Figure 3 shown, one end of the male rotor 2 is provided with an axon 21. The axon 21 extends to the outside of the air compressor housing 1, and an oil seal 4 is coated on the axon 21. The oil seal 4 is located outside the bearing 3. Preferably, a bush 6 is arranged between the oil seal 4 and the axon 21, and the bush 6 and the bearing 3 are separated by a spacer sleeve 7. An oil seal end cover 5 is arranged outside the oil seal 4, and the oil seal end cover 5 is fixedly arranged on the side surface of the air compressor housing 1. The oil seal end cover 5 is provided with a limiting flange 50, and the oil seal 4 is located inside the limiting flange 50. The oil seal 4 is limited by the limiting flange 50. Preferably, a dust-proof ring 8 is also arranged between the outer end of the oil seal end cover 5 and the axon 21 to prevent dust from entering and improve the service life of the oil seal 4. Preferably, an installation part 52 matching the inner diameter of the male rotor seat 11 is arranged inside the oil seal end cover 5 to facilitate the installation of the oil seal end cover 5. The oil seal end cover 5 seals the male rotor seat 11. A first cavity A is formed between the axon 21, the right side of the bearing 3, the left side of the oil seal 4, and the oil seal end cover 5, and a second cavity B is formed between the right side of the oil seal 4, the oil seal end cover 5, and the axon 21.

[0028] A first oil passage 51 is arranged at the lower part of the oil seal end cover 5. The first oil inlet 511 of the first oil passage 51 is located on the upper end surface of the limiting flange 50, that is, the first oil inlet 511 is located inside the second cavity B. The first oil outlet 512 of the first oil passage 51 is located on the side surface where the oil seal end cover 5 is connected to the air compressor housing 1.

[0029] The female rotor seat 12 is sealed by a female rotor end cover 121. A second oil passage 13 is arranged between the male rotor seat 11 and the female rotor seat 12. The second oil inlet 131 of the second oil passage 13 is located on the side surface of the air compressor housing 1, and the second oil inlet 131 is communicated with the first oil outlet 512. The second oil outlet 132 of the second oil passage 13 is located at the upper part of the female rotor seat 12.

[0030] A third oil passage 14 is provided at the lower part of the female rotor seat 12. The third oil inlet 141 of the third oil passage 14 is located inside the female rotor seat 12, and the third oil outlet 142 of the third oil passage 14 is located at the lower part of the air compressor housing 1. An air inlet seat 15 is also provided on the air compressor housing 1. A return oil pipe is connected between the third oil outlet 142 and the air inlet seat 15.

[0031] Preferably, a first opening 513 is further provided on the first oil passage 51. The first opening 513 is located at the bottom of the oil seal end cover 5. A first plug 5131 is provided on the first opening 513. The first opening 513 facilitates cleaning of the first oil passage 51.

[0032] Preferably, a second opening 143 is further provided on the third oil passage 14. The second opening 143 is located on the side surface of the air compressor housing 1. A second plug 1431 is provided on the second opening 143. The second opening 143 facilitates cleaning of the third oil passage 14.

[0033] As Figure 4 and Figure 5 shown, a fourth oil passage 53 is provided at the lower part of the oil seal end cover 5. The fourth oil inlet 531 of the fourth oil passage 53 is located at the inner lower side of the oil seal end cover 5 and inside the limit flange 50, that is, inside the first cavity A. The fourth oil outlet 532 of the fourth oil passage 53 is located on the end face inside the oil seal end cover 5. As Figure 6 and Figure 7 shown, a fifth oil passage 16 is provided on the air compressor housing 1. The fifth oil inlet 161 of the fifth oil passage 16 is communicated with the fourth oil outlet 532, and the fifth oil outlet 162 of the fifth oil passage 16 is communicated with the compression cavity inside the air compressor housing 1. The fourth oil passage 53 and the fifth oil passage 16 are used to send the lubricating oil in the first cavity A back to the compression cavity.

[0034] As Figure 3 shown, a throttling hole 54 is provided at the inner upper side of the oil seal end cover 5. The aperture of the outer side of the throttling hole 54 is smaller than that of the inner side. The throttling hole 54 is located inside the oil seal 4. The throttling hole 54 is used to reduce the pressure of the oil-gas mixture inside the air compressor housing 1 on the oil seal 4.

[0035] A screw air compressor uses the above-mentioned oil seal device.

[0036] When the above-mentioned oil seal device is working, the oil-gas mixture inside the air compressor housing 1 moves to the right and enters the first cavity A. Generally, the fourth oil passage 53 and the fifth oil passage 16 send the lubricating oil in the first cavity A back to the compression cavity. However, since the seal between the oil seal 4 and the male rotor 2 is a rotary seal, and the oil seal 4 is subjected to the pressure of the oil-gas mixture, after the machine runs for a period of time, the oil seal 4 will be deformed, and the inner diameter of the oil seal 4 will increase, resulting in a part of the lubricating oil in the first cavity A flowing into the second cavity B, then entering the first oil passage 51 through the first oil inlet 511, flowing out from the first oil outlet 512, entering the second oil passage 13 through the second oil inlet 131, flowing out from the second oil outlet 132, entering the female rotor seat 12, then flowing downward into the lower part of the female rotor seat 12, and then entering the third oil passage 14 through the third oil inlet 141, flowing out from the third oil outlet 142. The flowing lubricating oil flows through the oil return pipe to the air intake seat 15 and finally returns to the inside of the air compressor housing 1, thus solving the problem of oil leakage.

[0037] The advantage of the above-mentioned oil seal device is that even if the oil seal 4 is worn, the lubricating oil can finally return to the inside of the air compressor housing 1 through the first oil passage 51, the second oil passage 13, the third oil passage 14 and the oil return pipe, preventing oil leakage.

Claims

1. An oil seal device for a screw compressor, characterized in that, it includes an air compressor housing (1), a male rotor (2), a bearing (3), an oil seal (4) and an oil seal end cover (5); The air compressor housing (1) is provided with a male rotor seat (11) and a female rotor seat (12), and the male rotor seat (11) is located above the female rotor seat (12); the male rotor (2) is rotatably arranged on the male rotor seat (11) through the bearing (3), one end of the male rotor (2) is provided with an axon (21), the axon (21) extends to the outside of the air compressor housing (1), the axon (21) is covered with an oil seal (4), and the oil seal (4) is located outside the bearing (3), an oil seal end cover (5) is arranged outside the oil seal (4), and the oil seal end cover (5) is fixedly arranged on the side surface of the air compressor housing (1); a limiting flange (50) is arranged on the oil seal end cover (5), the oil seal (4) is located inside the limiting flange (50), and the oil seal (4) is limited by the limiting flange (50); A first oil passage (51) is arranged at the lower part of the oil seal end cover (5), a first oil inlet (511) of the first oil passage (51) is located on the upper end surface of the limiting flange (50), and a first oil outlet (512) of the first oil passage (51) is located on the side surface where the oil seal end cover (5) is connected to the air compressor housing (1); A second oil passage (13) is arranged between the male rotor seat (11) and the female rotor seat (12), a second oil inlet (131) of the second oil passage (13) is located on the side surface of the air compressor housing (1), and the second oil inlet (131) is communicated with the first oil outlet (512); a second oil outlet (132) of the second oil passage (13) is located inside the female rotor seat (12); The female rotor seat (12) is sealed by a female rotor end cover (121); a third oil passage (14) is arranged at the lower part of the female rotor seat (12), a third oil inlet (141) of the third oil passage (14) is located inside the female rotor seat (12), and a third oil outlet (142) of the third oil passage (14) is located at the lower part of the air compressor housing (1).

2. The oil seal device for a screw compressor according to claim 1, characterized in that, An air inlet seat (15) is further arranged on the air compressor housing (1), and a return oil pipe is connected between the third oil outlet (142) and the air inlet of the air inlet seat (15).

3. The oil seal device for a screw compressor according to claim 1, characterized in that, A shaft sleeve (6) is arranged between the oil seal (4) and the axon (21), and the shaft sleeve (6) and the bearing (3) are separated by a spacer sleeve (7); a dust-proof ring (8) is further arranged between the outer end of the oil seal end cover (5) and the axon (21).

4. The oil seal device for a screw compressor according to claim 1, characterized in that, An installation part (52) matching the inner diameter of the male rotor seat (11) is arranged on the inner side of the oil seal end cover (5).

5. The oil seal device for a screw compressor according to claim 1, characterized in that, A first oil passage (51) is further provided with a first opening (513). The first opening (513) is located at the bottom of the oil seal end cover (5), and a first plug (5131) is arranged on the first opening (513).

6. A kind of oil seal device of a screw compressor according to claim 1, characterized in that, A third oil passage (14) is further provided with a second opening (143). The second opening (143) is located on the side surface of the air compressor housing (1), and a second plug (1431) is arranged on the second opening (143).

7. A kind of oil seal device of a screw compressor according to claim 1, characterized in that, A fourth oil passage (53) is arranged at the lower part of the oil seal end cover (5). A fourth oil inlet (531) of the fourth oil passage (53) is located at the inner lower side of the oil seal end cover (5) and inside the limit flange (50). A fourth oil outlet (532) of the fourth oil passage (53) is located on the end surface inside the oil seal end cover (5); A fifth oil passage (16) is arranged on the air compressor housing (1). A fifth oil inlet (161) of the fifth oil passage (16) is communicated with the fourth oil outlet (532), and a fifth oil outlet (162) of the fifth oil passage (16) is communicated with the compression chamber inside the air compressor housing (1).

8. A kind of oil seal device of a screw compressor according to claim 1, characterized in that, The male rotor seat (11) is provided with a bearing seat (111), and a sixth oil passage (1111) communicated with the compression chamber inside the air compressor housing (1) is arranged on the bearing seat (111).

9. A kind of oil seal device of a screw compressor according to claim 1, characterized in that, A throttling hole (54) is arranged at the inner upper side of the oil seal end cover (5). The aperture outside the throttling hole (54) is smaller than that inside; The throttling hole (54) is located inside the oil seal (4).

10. A screw air compressor, characterized in that, This screw air compressor adopts the oil seal device described in any one of claims 1 to 9.

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