CN109595172B

CN109595172B - Double-stage compressor

Info

Publication number: CN109595172B
Application number: CN201710939500.5A
Authority: CN
Inventors: 黎法运; 杨开成; 虞阳波
Original assignee: Guangdong Meizhi Compressor Co Ltd
Current assignee: Guangdong Meizhi Compressor Co Ltd
Priority date: 2017-09-30
Filing date: 2017-09-30
Publication date: 2024-07-12
Anticipated expiration: 2037-09-30
Also published as: CN109595172A

Abstract

The invention discloses a two-stage compressor, which comprises: a housing defining a low pressure chamber, a medium pressure chamber and a high pressure chamber therein spaced apart from each other and arranged in sequence; pump body subassembly, pump body subassembly includes: the first-stage cylinder, the middle partition plate and the second-stage cylinder are sequentially arranged, a first compression cavity is defined in the first-stage cylinder, a second compression cavity is defined in the second-stage cylinder, the first-stage cylinder is located in the middle compression cavity, the second-stage cylinder is located in the high-pressure cavity, a first-stage air suction channel and a second-stage air suction channel are arranged on the pump body assembly, two ends of the first-stage air suction channel are respectively communicated with the low-pressure cavity and the first compression cavity, and two ends of the second-stage air suction channel are respectively communicated with the first compression cavity and the high-pressure cavity. According to the double-stage compressor, the first-stage air suction channel and the second-stage air suction channel which are communicated with the low-pressure cavity and the high-pressure cavity are arranged, so that the air suction resistance is reduced, and the energy efficiency of the compressor is improved.

Description

Double-stage compressor

Technical Field

The invention relates to the technical field of compressors, in particular to a two-stage compressor.

Background

In the related art, a casing of a dual-stage compressor is generally provided with a high-pressure cavity, a low-pressure cavity or a medium-pressure cavity. However, the above technical solution has the disadvantages of poor reliability in use, easy leakage of gas, etc. of the compressor, and affects the energy efficiency of the compressor.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides the double-stage compressor, which has good reliability and improved energy efficiency.

According to an embodiment of the present invention, a two-stage compressor includes: a housing defining a low pressure chamber, a medium pressure chamber and a high pressure chamber therein spaced apart from each other and arranged in sequence; pump body assembly, pump body assembly includes: the first-stage cylinder, the middle partition plate and the second-stage cylinder are sequentially arranged, a first compression cavity is defined in the first-stage cylinder, a second compression cavity is defined in the second-stage cylinder, the first-stage cylinder is located in the middle compression cavity, the second-stage cylinder is located in the high-pressure cavity, a first-stage air suction channel and a second-stage air suction channel are arranged on the pump body assembly, two ends of the first-stage air suction channel are respectively communicated with the low-pressure cavity and the first compression cavity, and two ends of the second-stage air suction channel are respectively communicated with the first compression cavity and the high-pressure cavity.

According to the two-stage compressor provided by the embodiment of the invention, the first-stage air suction channel and the second-stage air suction channel which are communicated with the low-pressure cavity and the high-pressure cavity are arranged, so that the air suction resistance is reduced, and the energy efficiency of the compressor is improved.

In addition, the two-stage compressor according to the above embodiment of the present invention has the following additional technical features:

According to some embodiments of the invention, the intermediate partition is provided with an intermediate partition suction opening configured as at least a portion of the second stage suction channel.

According to some embodiments of the invention, the pump body assembly further comprises: a main bearing provided at one end of the first stage cylinder away from the second stage cylinder, the main bearing being formed with a main bearing suction hole communicating with the low pressure chamber, the main bearing suction hole being configured as at least a part of the first stage suction passage; the auxiliary bearing is arranged at one end, far away from the first-stage cylinder, of the second-stage cylinder, an auxiliary bearing exhaust hole communicated with the high-pressure cavity is formed in the auxiliary bearing, and the auxiliary bearing exhaust hole is configured to be at least one part of the second-stage air suction channel.

Further, the method further comprises the following steps: the high-low pressure separation plate is arranged at one end of the main bearing, which is far away from the first-stage cylinder, and is provided with high-low pressure separation plate air suction holes which are respectively communicated with the low-pressure cavity and the main bearing air suction holes, and the high-low pressure separation plate air suction holes are configured into at least one part of the first-stage air suction channel.

Further, the high-low pressure partition plate suction holes are through holes penetrating through the high-low pressure partition plate in the thickness direction.

Further, the high-low pressure separation plate is also connected with a heat insulating piece, and at least one part of the heat insulating piece is positioned in the air suction hole of the high-low pressure separation plate.

Specifically, an exhaust baffle plate is further arranged between the main bearing and the first-stage cylinder, and an exhaust baffle plate air suction hole which is respectively communicated with the main bearing air suction hole and the first compression cavity is formed in the exhaust baffle plate.

Optionally, an exhaust partition plate is further arranged between the middle partition plate and the second-stage cylinder, and exhaust partition plate air suction holes which are respectively communicated with the middle partition plate air suction holes and the second compression cavity are formed in the exhaust partition plate.

Further, a stepped hole which is communicated with the medium pressure cavity and the middle partition plate air suction hole is formed on one side of the first-stage air cylinder, which is away from the exhaust partition plate, and the stepped hole is configured to be at least one part of the second-stage air suction channel.

Optionally, an annular groove is formed on the peripheral wall of the middle partition, and a sealing element is arranged in the annular groove so as to enable the shell to be in sealing connection with the middle partition.

Further, the intermediate pressure chamber is defined between the intermediate diaphragm, the seal, the housing, the main bearing, and the first stage cylinder.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 is a partial sectional view of a two-stage compressor according to a first embodiment of the present invention;

FIG. 2 is a partial sectional view of a two-stage compressor according to a second embodiment of the present invention;

Fig. 3 is a cross-sectional view of a dual stage compressor according to an embodiment of the present invention.

Reference numerals:

The dual-stage compressor 100 is configured to provide a fluid,

A housing 1, a low-pressure chamber 11, a medium-pressure chamber 12, a high-pressure chamber 13, a low-pressure housing 14, a high-pressure housing 15, a crankshaft 16, a motor 17,

Pump body assembly 2, first stage cylinder 21, first compression chamber 211, stepped hole 212, first suction hole 213, second stage cylinder 22, second compression chamber 221, second suction hole 222, middle partition 23, middle partition suction hole 231, annular groove 232, main bearing 24, main bearing suction hole 241, sub bearing 25,

High-low pressure partition plate 3, high-low pressure partition plate suction hole 31, heat insulator 4, exhaust partition plate 5, exhaust partition plate suction hole 51.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.

In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "radial," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, features defining "first", "second" may include one or more such features, either explicitly or implicitly. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The present invention relates to the field of rotary compressors, and more particularly, to a suction structure of a two-stage compressor and a rotary compressor using the same.

A two-stage compressor according to an embodiment of the present invention is described below with reference to the accompanying drawings. The two-stage compressor may be a horizontal compressor or a vertical compressor. For convenience of description, the present invention will be mainly described by taking a horizontal compressor as an example, however, this should not be construed as limiting the present invention.

As shown in fig. 1 to 3, a dual stage compressor 100 according to an embodiment of the present invention includes: housing 1 and pump body assembly 2.

Specifically, a low pressure chamber 11, a medium pressure chamber 12, and a high pressure chamber 13 are defined in the housing 1, which are spaced apart from each other and are arranged in this order. For example, a low pressure chamber 11, a medium pressure chamber 12, and a high pressure chamber 13 are defined in the casing 1, and the low pressure chamber 11, the medium pressure chamber 12, and the high pressure chamber 13 are spaced apart from each other and are arranged in order in the left-right direction shown in fig. 3.

The housing 1 includes a low-pressure housing 14 and a high-pressure housing 15, and the low-pressure housing 14 and the high-pressure housing 15 are connected. The housing 1 is further provided with a rotatable crankshaft 16, a balance passage is formed in the crankshaft 16 communicating with the low pressure chamber 11 and spaced apart from the high pressure chamber 13, and the balance passage penetrates through end surfaces of both ends of the crankshaft 16. A motor 17 may also be provided in the low pressure chamber 11 and the motor 17 is connected to the crankshaft 16, whereby the rotation of the crankshaft 16 may be powered by the motor 17.

The pump body assembly 2 includes: the first-stage cylinder 21, the middle partition plate 23 and the second-stage cylinder 22 which are sequentially arranged are arranged, a first compression cavity 211 is defined in the first-stage cylinder 21, a second compression cavity 221 is defined in the second-stage cylinder 22, the first-stage cylinder 21 is located in the medium-pressure cavity 12, the second-stage cylinder 22 is located in the high-pressure cavity 13, a first-stage air suction channel and a second-stage air suction channel are arranged on the pump body assembly 2, two ends of the first-stage air suction channel are respectively communicated with the low-pressure cavity 11 and the first compression cavity 211, and two ends of the second-stage air suction channel are respectively communicated with the first compression cavity 211 and the high-pressure cavity 13. Therefore, the first-stage air suction channel and the second-stage air suction channel which are communicated with the low-pressure cavity 11 and the high-pressure cavity 13 are arranged, so that the air suction resistance is reduced, and the energy efficiency of the compressor is improved.

Wherein the gas in the low pressure chamber 11 may be discharged into the high pressure chamber 13 through the first stage suction passage and the second stage suction passage in sequence.

According to the two-stage compressor 100 of the embodiment of the invention, the first-stage suction channel and the second-stage suction channel which are communicated with the low-pressure cavity 11 and the high-pressure cavity 13 are arranged, so that suction resistance is reduced, and energy efficiency of the compressor is improved.

Referring to fig. 3 in combination with fig. 1 and 2, according to one embodiment of the present invention, the middle partition 23 is provided with middle partition suction holes 231, and the middle partition suction holes 231 are configured as at least a part of the second stage suction passage. Thus, the gas in the low pressure chamber 11 can be further discharged from the first compression chamber 211, the middle partition suction hole 231 and the second compression chamber 221 through the first stage suction passage in sequence, which is beneficial to reducing suction resistance.

Referring to fig. 1 and 3, the pump body assembly 2 further includes: a main bearing 24 and a sub-bearing 25.

Specifically, the main bearing 24 is provided at an end of the first-stage cylinder 21 remote from the second-stage cylinder 22, and a main bearing suction hole 241 communicating with the low-pressure chamber 11 is formed in the main bearing 24, the main bearing suction hole 241 being configured as at least a part of the first-stage suction passage.

A sub-bearing 25 is provided at an end of the second stage cylinder 22 remote from the first stage cylinder 21, and a sub-bearing exhaust hole (not shown) communicating with the high pressure chamber 13 is formed in the sub-bearing 25, the sub-bearing exhaust hole being configured as at least a part of the second stage suction passage.

Thereby, the gas in the low pressure chamber 11 can be further discharged from the high pressure chamber 13 via the main bearing suction hole 241, the first compression chamber 211, the middle barrier suction hole 231, and the second compression chamber 221 in this order.

For example, in fig. 1, a main bearing 24 may be provided at the right end of the first stage cylinder 21, the main bearing 24 having a main bearing suction hole 241 formed thereon, the main bearing suction hole 241 may communicate with the low pressure chamber 11, the main bearing suction hole 241 being configured as at least a portion of the first stage suction passage.

Here, the main bearing suction hole 241 may be a through hole penetrating the main bearing 24 in a direction parallel to the axis of the crankshaft 16, or the main bearing suction hole 241 may be an inclined hole inclined with respect to the axis of the crankshaft 16.

A sub-bearing 25 may be provided at the left end of the second stage cylinder 22, and a sub-bearing exhaust hole is formed in the sub-bearing 25, the sub-bearing exhaust hole communicating with the high pressure chamber 13, the sub-bearing exhaust hole being configured as at least a portion of the second stage suction passage.

Referring to fig. 3, the dual stage compressor 100 further includes, according to some embodiments of the present invention: a high-low pressure separation plate 3, the high-low pressure separation plate 3 is provided at an end of the main bearing 24 remote from the first stage cylinder 21, and a high-low pressure separation plate suction hole 31 communicating the low pressure chamber 11 and the main bearing suction hole 241, respectively, is formed on the high-low pressure separation plate 3, the high-low pressure separation plate suction hole 31 being configured as at least a part of the first stage suction passage.

For example, high-low pressure separation plate 3 is provided at the right end of main bearing 24 and is connected to main bearing 24, and high-low pressure separation plate 3 is formed with high-low pressure separation plate suction holes 31, high-low pressure separation plate suction holes 31 communicating low-pressure chamber 11 and main bearing suction holes 241, respectively.

Wherein, the high-low pressure partition plate 3 is formed with a through high-low pressure partition plate suction hole 31, and the high-low pressure partition plate suction hole 31 communicates with the low pressure chamber 11 and the main bearing suction hole 241, respectively. Thereby, the gas in the low pressure chamber 11 can enter the first compression chamber 211 through the high and low pressure partition plate suction holes 31 and the main bearing suction holes 241 in sequence, enter the second compression chamber 221 through the middle pressure chamber 12 and then enter the second compression chamber 221 through the middle partition plate suction holes 231, and are conveyed to the high pressure chamber 13 through the auxiliary bearing exhaust holes.

Here, the high-low pressure separation plate suction hole 31 may be a through hole penetrating the high-low pressure separation plate 3 in a direction parallel to the axis of the crankshaft 16, or the high-low pressure separation plate suction hole 31 may be an inclined hole inclined with respect to the axis of the crankshaft 16.

Further, referring to fig. 3, the high-low pressure separation plate suction hole 31 is a through hole penetrating the thickness direction of the high-low pressure separation plate 3. For example, when the two-stage compressor 100 is a horizontal compressor, the high-low pressure separation plate suction hole 31 may be formed at the lower end (e.g., in the up-down direction shown in fig. 3) of the high-low pressure separation plate 3. Thereby, it is advantageous to avoid accumulation of the refrigerant oil in the low pressure chamber 11.

Further, referring to fig. 3, a heat insulator 4 is further connected to the high-low pressure separation plate 3, and at least a part of the heat insulator 4 is positioned in the high-low pressure separation plate suction hole 31. By providing the heat insulator 4, heat insulation can be performed, which is advantageous in improving the use reliability of the two-stage compressor 100.

Specifically, referring to fig. 2 and 3, an exhaust partition 5 is further provided between the main bearing 24 and the first stage cylinder 21, and an exhaust partition suction hole 51 communicating with the main bearing suction hole 241 and the first compression chamber 211, respectively, is formed in the exhaust partition 5.

In other words, an exhaust partition 5 may be further provided between the main bearing 24 and the first stage cylinder 21, and an exhaust partition suction hole 51 is formed in the exhaust partition 5, and the exhaust partition suction hole 51 communicates with the main bearing suction hole 241 and the first compression chamber 211, respectively. The first stage suction passage may be formed by the low pressure chamber 11, the main bearing suction hole 241, the discharge partition suction hole 51, and the first compression chamber 211.

Thereby, the gas in the low pressure chamber 11 can enter the first compression chamber 211 through the high and low pressure partition plate suction hole 31, the exhaust partition plate suction hole 51, and the main bearing suction hole 241 in this order, enter the second compression chamber 221 through the intermediate pressure chamber 12, and then enter the second compression chamber 221 through the middle partition plate suction hole 231, and are delivered to the high pressure chamber 13 through the auxiliary bearing exhaust hole.

Here, the exhaust partition plate suction hole 51 may be a through hole penetrating the exhaust partition plate 5 in a direction parallel to the axis of the crankshaft 16, or the exhaust partition plate suction hole 51 may be an inclined hole inclined with respect to the axis of the crankshaft 16. Referring to fig. 3, the exhaust diaphragm suction holes 51 may be coaxial with the high-low pressure partition plate suction holes 31 and the main bearing suction holes 241, and the radial dimensions of the exhaust diaphragm suction holes 51 and the radial dimensions of the high-low pressure partition plate suction holes 31 and the main bearing suction holes 241 may be equal. Thus, the suction resistance is reduced, and the energy efficiency of the compressor is improved.

Optionally, an exhaust partition (not shown) may be further disposed between the middle partition 23 and the second stage cylinder 22, and exhaust partition suction holes are formed in the exhaust partition, and respectively communicate with the middle partition suction holes 231 and the second compression chamber 221.

Here, the structure of the exhaust partition may be the same as that provided between the main bearing 24 and the first-stage cylinder 21 described above. The structure of the exhaust partition suction hole may be the same as that provided between the main bearing 24 and the first-stage cylinder 21.

Further, referring to fig. 1 and 3, a first suction hole 213 is formed in the first stage cylinder 21 to communicate the exhaust partition suction hole 51 and the first compression chamber 211, respectively, wherein the low pressure chamber 11, the main bearing suction hole 241, the exhaust partition suction hole 51, the first suction hole 213, and the first compression chamber 211 form a first stage suction passage.

Here, the central axis of the first suction hole 213 may be inclined toward the first compression chamber 211 with respect to the central axis of the exhaust partition suction hole 51. For example, in the example of fig. 3, the central axis of the first suction hole 213 may be inclined upward toward the first compression chamber 211 with respect to the central axis of the exhaust partition suction hole 51. The air suction resistance is reduced, and the energy efficiency of the compressor is improved.

According to an embodiment of the present invention, referring to fig. 3 in combination with fig. 2, the bottom of the high pressure chamber 13 is formed as an oil chamber, and the middle barrier suction hole 231 is provided at a position of the high pressure chamber 13 away from the oil chamber. For example, in fig. 3, the bottom of the high-pressure chamber 13 is formed as an oil chamber; in fig. 2, a middle partition suction hole 231 is provided at the upper end of the middle partition 23. Making the structure of the dual-stage compressor 100 more reasonable.

Alternatively, in combination with fig. 1 and 2, a stepped hole 212 (or a blind hole or the like) communicating with the intermediate pressure chamber 12 and the middle partition suction hole 231, respectively, is formed on a side of the first stage cylinder 21 facing away from the exhaust partition 5, and the stepped hole 212 is configured as at least a part of the second stage suction passage. Thus, the suction resistance is reduced.

For example, a stepped hole 212 is formed at the left side of the first stage cylinder 21, and the stepped hole 212 communicates with the middle pressure chamber 12 and the middle barrier suction hole 231, respectively, whereby the gas discharged from the first stage suction passage may be discharged into the high pressure chamber 13 through the middle pressure chamber 12, the stepped hole 212, the middle barrier suction hole 231, the second compression chamber 221, and the sub-bearing exhaust hole in this order.

Referring to fig. 3, optionally, an annular groove 232 is formed on the outer peripheral wall of the middle barrier 23, and a seal (not shown) is provided in the annular groove 232 to sealingly connect the housing 1 with the middle barrier 23. By providing a seal in the annular recess 232, a sealing connection between the housing 1 and the middle barrier 23 is thereby possible, so that a high-pressure chamber 13, a medium-pressure chamber 12 and a low-pressure chamber 11, which are spaced apart from one another, can be further defined in the housing 1.

Further, with reference to fig. 3, intermediate pressure chamber 12 is defined between intermediate diaphragm 23, the seal, housing 1, main bearing 24 and first stage cylinder 21. The gas in the low-pressure cavity 11 can be sequentially discharged into the medium-pressure cavity 12 through the first-stage air suction channel and then further discharged from the medium-pressure cavity 12 through the second-stage air suction channel, so that the air suction resistance of the compressor is reduced, and the energy efficiency of the compressor is improved.

The operation of the two-stage compressor 100 according to the embodiment of the present invention is described in detail below with reference to fig. 1 to 3. The suction structure of the dual stage compressor 100 includes a first stage suction passage and a second stage suction passage.

Specifically, the first-stage suction passage sucks the refrigerant from the low-pressure chamber 11 in the compressor housing into the first-stage cylinder 21, and is opened in the high-low pressure partition plate 3 (partition plate is connected to the suction hole), the main bearing 24, and the exhaust partition plate 5. The first stage cylinder 21 compresses the discharged refrigerant to flow into the intermediate pressure chamber 12, wherein the intermediate pressure chamber 12 is composed of the housing 1, the main bearing 24, the first stage cylinder 21, the intermediate partition plate 23 and the seal member, and is provided on the outer circumference of the first cylinder 21.

The second stage suction passage sucks the compressed refrigerant of the first stage cylinder 21 from the intermediate pressure chamber 12 to the second stage cylinder 22, and passes through the intermediate partition plate 23 and the second stage cylinder 22. The air suction structure designed in this way has small air suction resistance, compact structural design and high energy efficiency.

Gas is sucked in by the low pressure chamber 11 of the two-stage compressor 100, sequentially enters the first compression chamber 211 through the high-low pressure partition plate suction hole 31, the main bearing suction hole 241, the exhaust partition plate suction hole 51 and the first suction hole 213 of the first stage cylinder 21, and the compressed gas is discharged from the exhaust port of the first stage cylinder 212 to the medium pressure chamber 12, and the gas in the medium pressure chamber 12 is discharged into the high pressure chamber 13 through the auxiliary bearing exhaust hole sequentially through the step hole 212, the middle partition plate suction hole 231, the second suction hole 222 and the second compression chamber 221. The operation of the two-stage compressor 100 according to the embodiment of the present invention is completed.

Other configurations and operations of the dual stage compressor 100 according to embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail herein.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," 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 present invention. In this specification, schematic representations of the above terms are not necessarily directed 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. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the invention.

Claims

1. A two-stage compressor, comprising:

a housing defining a low pressure chamber, a medium pressure chamber and a high pressure chamber therein spaced apart from each other and arranged in sequence;

Pump body assembly, pump body assembly includes:

The first-stage cylinder, the middle partition plate and the second-stage cylinder are sequentially arranged, a first compression cavity is defined in the first-stage cylinder, a second compression cavity is defined in the second-stage cylinder, the first-stage cylinder is located in the middle compression cavity, the second-stage cylinder is located in the high-pressure cavity, a first-stage air suction channel and a second-stage air suction channel are arranged on the pump body assembly, two ends of the first-stage air suction channel are respectively communicated with the low-pressure cavity and the first compression cavity, and two ends of the second-stage air suction channel are respectively communicated with the first compression cavity and the high-pressure cavity.

2. The two-stage compressor according to claim 1, wherein a middle partition suction hole is provided on the middle partition, the middle partition suction hole being configured as at least a part of the second stage suction passage.

3. The dual stage compressor of claim 2, wherein the pump body assembly further comprises:

A main bearing provided at one end of the first stage cylinder away from the second stage cylinder, the main bearing being formed with a main bearing suction hole communicating with the low pressure chamber, the main bearing suction hole being configured as at least a part of the first stage suction passage;

the auxiliary bearing is arranged at one end, far away from the first-stage cylinder, of the second-stage cylinder, an auxiliary bearing exhaust hole communicated with the high-pressure cavity is formed in the auxiliary bearing, and the auxiliary bearing exhaust hole is configured to be at least one part of the second-stage air suction channel.

4. The dual stage compressor of claim 3, further comprising: the high-low pressure separation plate is arranged at one end of the main bearing, which is far away from the first-stage cylinder, and is provided with high-low pressure separation plate air suction holes which are respectively communicated with the low-pressure cavity and the main bearing air suction holes, and the high-low pressure separation plate air suction holes are configured into at least one part of the first-stage air suction channel.

5. The two-stage compressor according to claim 4, wherein the high-low pressure separation plate suction holes are through holes penetrating through the high-low pressure separation plate in the thickness direction.

6. The two-stage compressor according to claim 4, wherein the high-low pressure separator plate is further connected with a heat insulator, and at least a portion of the heat insulator is located in the high-low pressure separator plate suction hole.

7. The two-stage compressor according to claim 3, wherein an exhaust partition plate is further provided between the main bearing and the first stage cylinder, and an exhaust partition plate suction hole is formed in the exhaust partition plate to communicate the main bearing suction hole and the first compression chamber, respectively.

8. The two-stage compressor according to claim 3, wherein an exhaust partition plate is further provided between the middle partition plate and the second stage cylinder, and an exhaust partition plate suction hole is formed in the exhaust partition plate to be respectively communicated with the middle partition plate suction hole and the second compression chamber.

9. The two-stage compressor according to claim 7, wherein a side of the first stage cylinder facing away from the exhaust baffle is formed with a stepped hole communicating with the intermediate pressure chamber and the middle baffle suction hole, respectively, the stepped hole being configured as at least a part of the second stage suction passage.

10. The two-stage compressor according to claim 3, wherein an annular groove is formed in the outer peripheral wall of the middle partition plate, and a seal is provided in the annular groove to seal the housing to the middle partition plate.

11. The dual stage compressor of claim 10, wherein the intermediate pressure chamber is defined between the intermediate diaphragm, the seal, the housing, the main bearing, and the first stage cylinder.