Two-stage compressor and oil baffle mechanism

Abstract

The utility model relates to a two-stage compressor. A male rotor bearing cavity and a female rotor bearing cavity are formed in a low-pressure-stage exhaust end bearing seat of the double-stage compressor, and an oil supply passage for supplying lubricating oil to the male rotor bearing cavity and the female rotor bearing cavity is arranged in a seat body of the low-pressure-stage exhaust end bearing seat. A male rotor bearing for rotatably supporting the male rotor is arranged in the male rotor bearing chamber, and a female rotor bearing for rotatably supporting the female rotor is arranged in the female rotor bearing chamber. The male rotor bearing cavity and the female rotor bearing cavity are provided with a male rotor bearing cavity opening and a female rotor bearing cavity opening which face the high-pressure-stage machine body side respectively, a male rotor bearing cavity oil baffle plate for sealing the male rotor bearing cavity opening is arranged at the male rotor bearing cavity opening, and a female rotor bearing cavity oil baffle plate for sealing the female rotor bearing cavity opening is arranged at the female rotor bearing cavity opening. And a female rotor bearing cavity oil baffle plate for partially blocking the opening of the female rotor bearing cavity is arranged.

Description

Technical Field

[0001] The present application relates to the field of compressors, and in particular, to a two-stage compressor and an oil retaining mechanism for a bearing seat at a low-pressure stage exhaust end of the two-stage compressor. Background Art

[0002] With the requirements of compressor performance and energy efficiency, two-stage compressors have gradually developed from single-stage compressors. Such two-stage compressors usually include a low-pressure stage part and a high-pressure stage part. A low-pressure stage exhaust end bearing seat for accommodating bearings is arranged between the low-pressure stage part and the high-pressure stage part.

[0003] In a compressor, bearings are important parts to ensure efficient operation of the compressor. Since friction generates high temperatures when the compressor is working, if the bearings cannot be cooled effectively, it will lead to bearing damage, abnormal noise when the compressor is running, and eventually malfunction. There is still room for improvement in how to use a simple structure to ensure the lubrication effect of the bearings set in the low-pressure stage exhaust end bearing seat of a two-stage compressor. Utility Model Content

[0004] The present application is made in view of the technical problems existing in the above-mentioned prior art, and its purpose is to provide a two-stage compressor and an oil retaining mechanism, which can effectively improve the lubrication effect of the bearings in the low-pressure stage exhaust end bearing seat of the two-stage compressor with a simple structure.

[0005] According to one scheme of the present application, a two-stage compressor is provided, which includes a low-pressure stage body, a high-pressure stage body, and a low-pressure stage exhaust end bearing seat arranged between the low-pressure stage body and the high-pressure stage body, and a male rotor and a female rotor that mesh with each other are arranged in the low-pressure stage body. A male rotor bearing cavity and a female rotor bearing cavity are arranged inside the low-pressure stage exhaust end bearing seat, and an oil supply passage for supplying lubricating oil to the male rotor bearing cavity and the female rotor bearing cavity respectively is arranged in the seat body of the low-pressure stage exhaust end bearing seat, a male rotor bearing for rotatably supporting the male rotor is arranged in the male rotor bearing cavity, and a female rotor bearing for rotatably supporting the female rotor is arranged in the female rotor bearing cavity, the male rotor bearing cavity and the female rotor bearing cavity respectively have a male rotor bearing cavity opening and a female rotor bearing cavity opening facing the high-pressure stage body side, and a female rotor bearing cavity oil baffle plate for partially blocking the female rotor bearing cavity opening is arranged at the female rotor bearing cavity opening, the female rotor bearing comprises a bearing outer ring, a bearing inner ring and a rolling body that can be rollably arranged between the bearing outer ring and the bearing inner ring, when the minimum height of the female rotor bearing cavity oil baffle plate in the vertical direction is h, the dimension from the radial outer surface of the bearing outer ring to the radial inner surface of the bearing inner ring is hmax The dimension from the radial outer surface of the bearing outer ring to the center of the rolling element is h. min , when the diameter of the rolling element is D, the oil baffle of the female rotor bearing cavity is configured to satisfy the following relationship:

[0006] △h = h max - h = h - h min (1)

[0007] D / 10 ≤ △h ≤ D / 5 (2).

[0008] In the above-mentioned two-stage compressor, the minimum height h of the oil baffle of the female rotor bearing cavity in the vertical direction is set so that the lubricating oil in the female rotor bearing cavity can immerse the rolling element in the female rotor bearing that is located at the bottom in the vertical direction, and so that the inner ring of the bearing is located above the liquid level of the lubricating oil in the female rotor bearing cavity.

[0009] In the above two-stage compressor, a yang rotor bearing cavity oil baffle plate is provided at the opening of the yang rotor bearing cavity to seal the opening of the yang rotor bearing cavity.

[0010] In any of the above two-stage compressors, the oil baffle of the male rotor bearing cavity and the seat body of the low-pressure stage exhaust end bearing seat are provided with an oil return passage connecting the male rotor bearing cavity with the interior of the low-pressure stage body.

[0011] In any of the above two-stage compressors, the male rotor bearing cavity oil baffle plate and the female rotor bearing cavity oil baffle plate are formed integrally.

[0012] In any of the above two-stage compressors, the male rotor bearing cavity oil baffle plate and the female rotor bearing cavity oil baffle plate are formed integrally.

[0013] In any of the above two-stage compressors, the oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

[0014] In any of the above two-stage compressors, the oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

[0015] In any of the above two-stage compressors, the female rotor bearing cavity oil baffle is provided with a fastening screw for axially positioning the bearing outer ring of the female rotor bearing.

[0016] According to another embodiment of the present application, an oil retaining mechanism for a low-pressure stage exhaust end bearing seat of a two-stage compressor is provided. The two-stage compressor comprises a low-pressure stage body and a high-pressure stage body, the low-pressure stage exhaust end bearing seat is arranged between the low-pressure stage body and the high-pressure stage body, and a male rotor and a female rotor meshing with each other are arranged in the low-pressure stage body. A male rotor bearing cavity and a female rotor bearing cavity are arranged inside the low-pressure stage exhaust end bearing seat, and an oil supply passage for supplying lubricating oil to the male rotor bearing cavity and the female rotor bearing cavity respectively is arranged in the seat body of the low-pressure stage exhaust end bearing seat, a male rotor bearing for rotatably supporting the male rotor is arranged in the male rotor bearing cavity, and a female rotor bearing for rotatably supporting the female rotor is arranged in the female rotor bearing cavity, the male rotor bearing cavity and the female rotor bearing cavity respectively have a male rotor bearing cavity opening and a female rotor bearing cavity opening facing the high-pressure stage body side, the oil blocking mechanism comprises a female rotor bearing cavity oil blocking plate, the female rotor bearing cavity oil blocking plate is arranged at the female rotor bearing cavity opening, and partially blocks the female rotor bearing cavity opening, the female rotor bearing comprises a bearing outer ring, a bearing inner ring and a rolling body that can be rollably arranged between the bearing outer ring and the bearing inner ring, when the minimum height of the female rotor bearing cavity oil blocking plate in the vertical direction is h, the dimension from the radial outer surface of the bearing outer ring to the radial inner surface of the bearing inner ring is h max The dimension from the radial outer surface of the bearing outer ring to the center of the rolling element is h. min , when the diameter of the rolling element is D, the oil baffle of the female rotor bearing cavity is configured to satisfy the following relationship:

[0017] △h = h max - h = h - h min (1)

[0018] D / 10 ≤ △h ≤ D / 5 (2).

[0019] In the above-mentioned oil baffle mechanism, the minimum height h of the oil baffle plate of the female rotor bearing cavity in the vertical direction is set so that the lubricating oil in the female rotor bearing cavity can immerse the rolling element in the female rotor bearing that is located at the bottom in the vertical direction, and so that the inner ring of the bearing is located above the liquid level of the lubricating oil in the female rotor bearing cavity.

[0020] In any of the above-mentioned oil baffle mechanisms, it also includes a male rotor bearing cavity oil baffle plate, and the male rotor bearing cavity oil baffle plate is arranged at the male rotor bearing cavity opening to seal the male rotor bearing cavity opening.

[0021] In any of the above oil baffle mechanisms, the oil baffle plate of the male rotor bearing cavity and the seat body of the low-pressure stage exhaust end bearing seat are provided with an oil return passage connecting the male rotor bearing cavity with the interior of the low-pressure stage body.

[0022] In any of the above oil baffle mechanisms, the oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed integrally.

[0023] In any of the above oil baffle mechanisms, the oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed integrally.

[0024] In any of the above-mentioned oil baffle mechanisms, the oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

[0025] In any of the above-mentioned oil baffle mechanisms, the oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

[0026] In any of the above-mentioned oil baffle mechanisms, the female rotor bearing cavity oil baffle plate is provided with a fastening screw for axially positioning the bearing outer ring of the female rotor bearing.

[0027] According to the two-stage compressor or oil-blocking mechanism of the present application, the opening of the female rotor bearing cavity is partially blocked by using the female rotor bearing cavity oil-blocking plate, so that the female rotor bearing cavity forms an open structure, so that the oil-containing air flow circulating in the female rotor bearing cavity also plays a role in lubricating the bearing, thereby achieving the improvement of the lubrication effect of the bearing in the low-pressure stage exhaust end bearing seat of the two-stage compressor with a simple structure, and achieving the effect of improving the cooling of the male rotor. Furthermore, when the minimum height of the female rotor bearing cavity oil-blocking plate in the vertical direction is h, the dimension from the radial outer surface of the bearing outer ring to the radial inner surface of the bearing inner ring is h max The dimension from the radial outer surface of the bearing outer ring to the center of the rolling element is h. min When the diameter of the rolling element is D, the minimum height h of the oil baffle plate of the female rotor bearing cavity in the vertical direction is set to satisfy △h=h max -h=hh min And the relationship of D / 10≤△h≤D / 5, on the one hand, can keep the lubricating oil in the female rotor bearing cavity at a sufficient static liquid level, thereby reducing the oil supply time difference when the two-stage compressor is started and preventing abnormal noise caused by the failure to form a surface oil film on the rolling element of the female rotor bearing in time; on the other hand, it can avoid the phenomenon of oil stirring in the inner ring of the female rotor bearing after the two-stage compressor is started due to excessive oil storage in the female rotor bearing cavity, thereby suppressing the noise and heat caused by the oil stirring in the inner ring of the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 1 is a schematic longitudinal sectional view showing a two-stage compressor according to the present application.

[0029] Figure 2 It means from Figure 1 Schematic partial cross-sectional view of a two-stage compressor when viewed from above.

[0030] Figure 3 It is a schematic side cross-sectional view showing a two-stage compressor when viewed from the high-pressure stage side.

[0031] Figure 4 It is a schematic diagram showing a male rotor bearing cavity baffle and a female rotor bearing cavity baffle formed integrally according to an embodiment of the present application.

[0032] Figure 5 It is a schematic partial cross-sectional view viewed from the male rotor bearing chamber side.

[0033] Figure 6 It is a schematic partial cross-sectional view viewed from the female rotor bearing chamber side.

[0034] Figure 7 1 is a schematic diagram of a low-pressure stage exhaust end bearing seat provided with a male rotor bearing cavity baffle and a female rotor bearing cavity baffle formed independently according to another embodiment of the present application.

[0035] Figure 8 Yes means Figure 7 A perspective view of the female rotor bearing cavity baffle in the illustrated embodiment.

[0036] Fig. 9 It is a schematic diagram showing the axial positioning effect of the fastening screws arranged on the baffle plate of the female rotor bearing cavity on the bearing.

[0037] Fig.10 It is a schematic diagram used to illustrate the minimum height of the baffle of the female rotor bearing cavity.

[0038] Description of reference numerals:

[0039] 1 two-stage compressor, 10 oil baffle, 10a male rotor bearing cavity oil baffle, 10b female rotor bearing cavity oil baffle, 15, oil drain port, 20 rolling element, 30 female rotor bearing, 30a bearing inner ring, 30b bearing outer ring, 31 male rotor bearing, 40 low-pressure exhaust end bearing seat, 41 male rotor bearing cavity, 41a male rotor bearing cavity opening, 42 female rotor bearing cavity, 42a female rotor bearing cavity opening, 43 oil supply passage, 44 oil return passage, 50 high-pressure stage body, 60 low-pressure stage body, 80 fastening screws, 90 male rotor, 100 female rotor DETAILED DESCRIPTION

[0040] The present application is described in detail below. In the following paragraphs, different aspects of the embodiments are defined in more detail. Each aspect defined in this way can be combined with any other aspect or aspects, unless it is clearly stated that it cannot be combined. In particular, any feature that is considered to be preferred or advantageous can be combined with one or more other features that are considered to be preferred or advantageous.

[0041] The terms "first", "second", etc. that appear in this application are only for the convenience of description to distinguish different components with the same name, and do not indicate a sequence or a primary or secondary relationship.

[0042] Furthermore, when a component is referred to as being “on” another component, the component may be directly on the other component, or may be indirectly on the other component with one or more intermediate components interposed therebetween. Additionally, when a component is referred to as being “connected to” another component, the component may be directly connected to the other component, or may be indirectly connected to the other component with one or more intermediate components interposed therebetween. Hereinafter, the same reference numerals denote the same components.

[0043] In the present application, descriptions of directions or positional relationships indicated by “upper”, “lower”, “top”, “bottom”, “front”, “back”, “inside” and “outside” are used only to facilitate the description of the present application, and do not indicate or imply that the device referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, it should not be understood as limiting the scope of protection of the present application.

[0044] Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings.

[0045] First, refer to Figure 1 and Figure 2 , explaining the overall structure of the two-stage compressor.

[0046] like Figure 1 and Figure 2 As shown, the two-stage compressor 1 includes a high-pressure stage body 50 and a low-pressure stage body 60. A male rotor 90 and a female rotor 100 for compressing gas are arranged in the low-pressure stage body 60. The male rotor 90 and the female rotor 100 mesh with each other and rotate in opposite directions, thereby compressing the gas. Similarly, a screw compression structure including a male rotor and a female rotor is also arranged in the high-pressure stage body 50. A low-pressure stage exhaust end bearing seat 40 is arranged between the high-pressure stage body 50 and the low-pressure stage body 60 (i.e., the exhaust end of the low-pressure stage body 60), and a female rotor bearing cavity 41 and a male rotor bearing cavity 42 are formed inside the low-pressure stage exhaust end bearing seat 40.

[0047] A female rotor bearing 30 for supporting the female rotor 100 is disposed in the female rotor bearing cavity 41. The female rotor bearing 30 may include one or more bearings. For example, in the example shown in the figure, the female rotor bearing 30 includes two ball bearings and one roller bearing. However, it should be understood that the present invention is not limited thereto, and the female rotor bearing 30 may include a combination of any number and type of bearings.

[0048] Similarly, a male rotor bearing 31 for supporting the male rotor 90 is disposed in the male rotor bearing cavity 42. The male rotor bearing 31 may include one or more bearings. For example, in the example shown in the figure, the male rotor bearing 31 includes two ball bearings and one roller bearing. However, it should be understood that the present invention is not limited thereto, and the male rotor bearing 31 may also include a combination of any number and type of bearings.

[0049] In addition, an oil supply passage 43 is formed in the low-pressure stage exhaust end bearing seat 40 and is connected to the male rotor bearing cavity 41 and the female rotor bearing cavity 42 respectively, for supplying lubricating oil for lubrication and cooling to the male rotor bearing 31 arranged in the male rotor bearing cavity 41 and the female rotor bearing 30 arranged in the female rotor bearing cavity 42 respectively.

[0050] When the compressor is working, the male rotor bearing 31 and the female rotor bearing 30 respectively support the male rotor 90 and the female rotor 100 for rotation. Therefore, high temperature is generated due to the friction during rotation, which has an adverse effect on the performance of the lubricating oil, resulting in poor lubrication of the bearings by the lubricating oil, causing damage to the bearings, thereby causing abnormal noise when the compressor is running and ultimately failing to work normally.

[0051] On the other hand, when the compressor is working, the male rotor 90 and the female rotor 100 mesh with each other and rotate to compress the air. Therefore, high temperature will be generated due to the friction during rotation, which will also have an adverse effect on the performance of the lubricating oil.

[0052] In order to solve the above problems, according to the utility model of the present application, a female rotor bearing chamber oil baffle 10b is provided at the female rotor bearing chamber opening 42a of the female rotor bearing chamber 42. In addition, preferably, a male rotor bearing chamber oil baffle 10a may also be provided at the male rotor bearing chamber opening 41a of the male rotor bearing chamber 41. In order to facilitate the understanding of the present application, the following is an example of the case where both the female rotor bearing chamber oil baffle 10b and the male rotor bearing chamber oil baffle 10a are provided. However, it should be understood that according to the utility model of the present application, as long as the female rotor bearing chamber oil baffle 10b is provided, the male rotor bearing chamber oil baffle 10a may be omitted.

[0053] exist Figure 3 and Figure 4In the illustrated embodiment, the male rotor bearing cavity oil baffle plate 10a and the female rotor bearing cavity oil baffle plate 10b are integrally formed to form the oil baffle plate 10. In this case, the male rotor bearing cavity oil baffle plate 10a refers to the portion of the oil baffle plate 10 that is opposite to the male rotor bearing cavity opening 41a. The female rotor bearing cavity oil baffle plate 10b refers to the portion of the oil baffle plate 10 that is opposite to the female rotor bearing cavity opening 42a.

[0054] like Figure 3 As shown, the male rotor bearing cavity oil baffle plate 10a completely closes the male rotor bearing cavity opening 41a of the male rotor bearing cavity 41 so as to seal the male rotor bearing cavity 41; on the other hand, the female rotor bearing cavity oil baffle plate 10b does not completely close the female rotor bearing cavity opening 42a of the female rotor bearing cavity 42, but only partially blocks the female rotor bearing cavity opening 42a, so that the female rotor bearing cavity opening 42a is partially opened. In the portion where the female rotor bearing cavity oil baffle plate 10b does not block the female rotor bearing cavity opening 42a, an oil drain port 15 is formed to allow the oil supplied to the female rotor bearing cavity 42 to flow out of the female rotor bearing cavity 42.

[0055] In addition, if Figure 5 As shown, preferably, an oil return passage 44 can be formed in the male rotor bearing cavity oil baffle plate 10a and the low-pressure stage exhaust end bearing seat 40. Since the male rotor bearing cavity opening 41a of the male rotor bearing cavity 41 is closed by the male rotor bearing cavity oil baffle plate 10a, the lubricating oil supplied to the male rotor bearing cavity 41 cannot flow outward through the male rotor bearing cavity opening 41a, but returns to the low-pressure stage body 60 via the oil return passage 44 formed in the male rotor bearing cavity oil baffle plate 10a and the low-pressure stage exhaust end bearing seat 40.

[0056] Thus, the positive rotor bearing cavity opening 41a of the positive rotor bearing cavity 41 is completely closed by utilizing the positive rotor bearing cavity oil baffle 10a, and the lubricating oil in the positive rotor bearing cavity 41 is returned to the low-pressure stage body 60 via the return oil passage 44. The returned lubricating oil can cool the positive rotor 90 and the negative rotor 100 arranged in the low-pressure stage body 60, thereby improving the energy efficiency of the two-stage compressor.

[0057] Furthermore, by using the female rotor bearing cavity oil baffle 10b to partially block the female rotor bearing cavity opening 42a of the female rotor bearing cavity 42 and forming the oil drain port 15, on the one hand, the oil storage height in the female rotor bearing cavity 42 can be ensured so as to provide sufficient lubrication for the female rotor bearing, and on the other hand, the additional heating and noise caused by the oil stirring of the bearing inner ring 30a due to the excessive amount of lubricating oil in the female rotor bearing cavity 42 can be avoided. In addition, the lubricating oil flows out from the female rotor bearing cavity 42 through the oil drain port 15, which can take out the heat generated by the friction of the female rotor bearing 30 during high-speed operation, thereby reducing the temperature of the bearing surface, reducing the heat generated by the bearing, extending the fatigue life of the bearing, and improving the energy efficiency of the two-stage compressor 1.

[0058] In the above, the embodiment in which the oil baffle plate 10 is formed integrally by the male rotor bearing cavity oil baffle plate 10a and the female rotor bearing cavity oil baffle plate 10b is described. However, the present invention is not limited to this. For example, Figure 7 As shown, the oil baffle plate 10 may also be composed of a male rotor bearing chamber oil baffle plate 10a and a female rotor bearing chamber oil baffle plate 10b which are independently formed. In this case, the male rotor bearing chamber oil baffle plate 10a is formed to seal the male rotor bearing chamber opening 41a of the male rotor bearing chamber 41 in the same manner as described above, while the female rotor bearing chamber oil baffle plate 10b is formed to block only the portion of the female rotor bearing chamber opening 42a located at the lower part in the vertical direction, leaving the portion of the female rotor bearing chamber opening 42a located at the upper part in the vertical direction open.

[0059] By adopting the above structure, the lubricating oil in the male rotor bearing cavity 41 can also flow back to the interior of the low-pressure stage body 60, so as to cool the male rotor 90 and the female rotor 100 that mesh and rotate with each other, and at the same time, a certain oil storage height is maintained in the female rotor bearing cavity 42, and the lubricating oil exceeding the oil storage height is made to flow out over the female rotor bearing cavity oil baffle 10b. Therefore, the oil baffle of this structure can achieve the same technical effect as the above-mentioned embodiment.

[0060] In addition, preferably, a fastening screw 80 may also be provided on the female rotor bearing chamber oil baffle 10b. Figure 8 and Fig. 9 , an example is shown in which the fastening bolts 80 are provided on the female rotor bearing cavity oil baffle plate 10b when the female rotor bearing cavity oil baffle plate 10b and the male rotor bearing cavity oil baffle plate 10a are formed separately. However, it should be understood that the fastening bolts 80 may also be provided when the female rotor bearing cavity oil baffle plate 10b and the male rotor bearing cavity oil baffle plate 10a are formed integrally to form the oil baffle plate 10.

[0061] like Fig. 9As shown, by setting a fastening screw 80 on the female rotor bearing cavity oil baffle plate 10b, when the female rotor bearing cavity oil baffle plate 10b is installed in the female rotor bearing cavity opening 42a, by tightening the fastening screw 80, the bearing outer ring 30b of the female rotor bearing 30 can be axially positioned by the fastening screw 80, thereby reducing the risk of the bearing falling off or loosening.

[0062] The present application has no limitation on the size of the female rotor bearing cavity oil baffle 10 b (or the size of the oil drain port 15 ), as long as the lubricating oil in the female rotor bearing cavity 42 can flow out.

[0063] like Fig.10 As shown, the female rotor bearing 30 includes a bearing outer ring 30b, a bearing inner ring 30a, and a plurality of rolling bodies 20 that are rollably disposed between the bearing outer ring 30b and the bearing inner ring 30a. Fig.10 As shown, the minimum height of the oil baffle of the female rotor bearing cavity in the vertical direction is h, and the dimension from the radial outer surface of the bearing outer ring 30b to the radial inner surface of the bearing inner ring 30a is h max The dimension from the radial outer surface of the bearing outer ring 30b to the center of the rolling element 20 is h min , the diameter of the rolling element is D. In this case, the oil baffle of the female rotor bearing cavity is set to satisfy the following relationship:

[0064] △h = h max - h = h - h min (1)

[0065] D / 10 ≤ △h ≤ D / 5 (2)

[0066] When the minimum height of the female rotor bearing cavity oil baffle 10b in the vertical direction is h, the dimension from the radial outer surface of the bearing outer ring 30b of the female rotor bearing 30 to the radial inner surface of the bearing inner ring 30a of the female rotor bearing 30 is h. max The dimension from the radial outer surface of the bearing outer ring 30b to the center of the rolling element 20 of the female rotor bearing 30 is h. min , and when the diameter of the rolling element 20 is D, the minimum height h of the female rotor bearing chamber oil baffle 10b in the vertical direction is set to satisfy △h=h max -h=hh minAnd the relationship of D / 10≤△h≤D / 5, on the one hand, can make the lubricating oil in the female rotor bearing cavity 41 maintain a sufficient static liquid level, thereby reducing the oil supply time difference when the two-stage compressor 1 is started, and preventing abnormal noise caused by the failure to form a surface oil film on the rolling element 20 of the female rotor bearing 30 in time; on the other hand, it can avoid the phenomenon of oil stirring of the inner ring 30a of the female rotor bearing 31 after the two-stage compressor 1 is started due to the excessive amount of lubricating oil in the female rotor bearing cavity 42, thereby suppressing the noise and heat caused by the oil stirring of the inner ring 30a of the bearing. Therefore, by setting the minimum height h of the female rotor bearing cavity oil baffle 10b to satisfy the above relationship, it can prevent the destruction of the oil film on the rolling element 20, the direct contact between metal and metal, reduce bearing friction and wear, and avoid noise and heat caused by the inner ring 30a of the bearing.

[0067] Furthermore, preferably, the minimum height h of the female rotor bearing cavity oil baffle 10b in the vertical direction is set so that the lubricating oil in the female rotor bearing cavity 42 can immerse the rolling element 20 located at the bottom in the vertical direction among the multiple rolling elements 20 of the female rotor bearing 30, and the inner ring 30a of the bearing is located above the liquid surface of the lubricating oil in the female rotor bearing cavity. In this way, the rolling elements 20 of the female rotor bearing 30 in the female rotor bearing cavity 42 can be fully infiltrated, and the inner ring 30a of the bearing will not be stirred. In addition, the oil supply time difference generated when the two-stage compressor 1 is started is reduced, and the abnormal sound caused by the failure to form an oil film on the surface of the rolling element 20 in time is avoided, and the noise and heat caused by the stirring of the oil in the inner ring 30 of the bearing are prevented.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A two-stage compressor, comprising a low-pressure stage body, a high-pressure stage body, and a low-pressure stage exhaust end bearing seat arranged between the low-pressure stage body and the high-pressure stage body, wherein a male rotor and a female rotor meshing with each other are arranged in the low-pressure stage body, characterized in that: A male rotor bearing cavity and a female rotor bearing cavity are arranged inside the low-pressure stage exhaust end bearing seat, and an oil supply passage for supplying lubricating oil to the male rotor bearing cavity and the female rotor bearing cavity respectively is arranged in the seat body of the low-pressure stage exhaust end bearing seat, a male rotor bearing for rotatably supporting the male rotor is arranged in the male rotor bearing cavity, and a female rotor bearing for rotatably supporting the female rotor is arranged in the female rotor bearing cavity, the male rotor bearing cavity and the female rotor bearing cavity respectively have a male rotor bearing cavity opening and a female rotor bearing cavity opening facing the high-pressure stage body side, A female rotor bearing cavity oil baffle plate is provided at the female rotor bearing cavity opening to partially block the female rotor bearing cavity opening. The female rotor bearing comprises a bearing outer ring, a bearing inner ring and a rolling body that can be rolled between the bearing outer ring and the bearing inner ring. When the minimum height of the female rotor bearing cavity oil baffle in the vertical direction is h, the dimension from the radial outer surface of the bearing outer ring to the radial inner surface of the bearing inner ring is h. max The dimension from the radial outer surface of the bearing outer ring to the center of the rolling element is h. min , when the diameter of the rolling element is D, the oil baffle of the female rotor bearing cavity is configured to satisfy the following relationship: △h = h max - h = h - h min (1) D / 10 ≤ △h ≤ D / 5 (2).

2. The two-stage compressor according to claim 1, characterized in that: The minimum height h of the oil baffle of the female rotor bearing cavity in the vertical direction is set so that the lubricating oil in the female rotor bearing cavity can immerse the rolling element located at the bottom in the female rotor bearing in the vertical direction, and so that the inner ring of the bearing is located above the liquid level of the lubricating oil in the female rotor bearing cavity.

3. The two-stage compressor according to claim 1 or 2, characterized in that: A yang rotor bearing cavity oil baffle plate is provided at the opening of the yang rotor bearing cavity to seal the opening of the yang rotor bearing cavity.

4. The two-stage compressor according to claim 3, characterized in that: The oil baffle plate of the male rotor bearing cavity and the seat body of the low-pressure stage exhaust end bearing seat are provided with an oil return passage connecting the male rotor bearing cavity with the interior of the low-pressure stage body.

5. The two-stage compressor according to claim 3, characterized in that: The male rotor bearing cavity oil baffle plate and the female rotor bearing cavity oil baffle plate are formed integrally.

6. The two-stage compressor according to claim 4, characterized in that The male rotor bearing cavity oil baffle plate and the female rotor bearing cavity oil baffle plate are formed integrally.

7. The two-stage compressor according to claim 3, characterized in that: The oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

8. The two-stage compressor according to claim 4, characterized in that: The oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

9. The two-stage compressor according to claim 1 or 2, characterized in that: The female rotor bearing cavity oil baffle is provided with a fastening screw for axially positioning the bearing outer ring of the female rotor bearing.

10. An oil retaining mechanism for a low-pressure stage exhaust end bearing seat of a two-stage compressor, the two-stage compressor comprising a low-pressure stage body and a high-pressure stage body, the low-pressure stage exhaust end bearing seat being arranged between the low-pressure stage body and the high-pressure stage body, a male rotor and a female rotor meshing with each other being arranged in the low-pressure stage body, characterized in that: A male rotor bearing cavity and a female rotor bearing cavity are arranged inside the low-pressure stage exhaust end bearing seat, and an oil supply passage for supplying lubricating oil to the male rotor bearing cavity and the female rotor bearing cavity respectively is arranged in the seat body of the low-pressure stage exhaust end bearing seat, a male rotor bearing for rotatably supporting the male rotor is arranged in the male rotor bearing cavity, and a female rotor bearing for rotatably supporting the female rotor is arranged in the female rotor bearing cavity, the male rotor bearing cavity and the female rotor bearing cavity respectively have a male rotor bearing cavity opening and a female rotor bearing cavity opening facing the high-pressure stage body side, The oil blocking mechanism comprises a female rotor bearing cavity oil blocking plate, wherein the female rotor bearing cavity oil blocking plate is arranged at the female rotor bearing cavity opening to partially block the female rotor bearing cavity opening. The female rotor bearing comprises a bearing outer ring, a bearing inner ring and a rolling body that can be rolled between the bearing outer ring and the bearing inner ring. When the minimum height of the female rotor bearing cavity oil baffle in the vertical direction is h, the dimension from the radial outer surface of the bearing outer ring to the radial inner surface of the bearing inner ring is h. max The dimension from the radial outer surface of the bearing outer ring to the center of the rolling element is h. min , when the diameter of the rolling element is D, the oil baffle of the female rotor bearing cavity is configured to satisfy the following relationship: △h = h max - h = h - h min (1) D / 10 ≤ △h ≤ D / 5 (2).

11. The oil retaining mechanism according to claim 10, characterized in that: The minimum height h of the oil baffle of the female rotor bearing cavity in the vertical direction is set so that the lubricating oil in the female rotor bearing cavity can immerse the rolling element located at the bottom in the female rotor bearing in the vertical direction, and so that the inner ring of the bearing is located above the liquid level of the lubricating oil in the female rotor bearing cavity.

12. The oil retaining mechanism according to claim 10 or 11, characterized in that: The oil baffle mechanism also includes a male rotor bearing cavity oil baffle plate, and the male rotor bearing cavity oil baffle plate is arranged at the male rotor bearing cavity opening to seal the male rotor bearing cavity opening.

13. The oil blocking mechanism according to claim 12, characterized in that: The oil baffle plate of the male rotor bearing cavity and the seat body of the low-pressure stage exhaust end bearing seat are provided with an oil return passage connecting the male rotor bearing cavity with the interior of the low-pressure stage body.

14. The oil blocking mechanism according to claim 12, characterized in that: The male rotor bearing cavity oil baffle plate and the female rotor bearing cavity oil baffle plate are formed integrally.

15. The oil blocking mechanism according to claim 13, characterized in that: The male rotor bearing cavity oil baffle plate and the female rotor bearing cavity oil baffle plate are formed integrally.

16. The oil blocking mechanism according to claim 12, characterized in that: The oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

17. The oil blocking mechanism according to claim 13, characterized in that: The oil baffle plate of the male rotor bearing cavity and the oil baffle plate of the female rotor bearing cavity are formed independently.

18. The oil retaining mechanism according to claim 10 or 11, characterized in that: The female rotor bearing cavity oil baffle is provided with a fastening screw for axially positioning the bearing outer ring of the female rotor bearing.

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