Rotor assemblies, compressors, and air conditioners

The rotor assembly in compressors applies a unidirectional axial force to balance rotor forces, reducing size and cost by eliminating redundant thrust bearings while maintaining capacity.

JP7833465B2Active Publication Date: 2026-03-19GREE ELECTRIC APPLIANCE INC OF ZHUHAI
View PDF 3 Cites 0 Cited by

Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2021-10-25
Publication Date
2026-03-19

AI Technical Summary

Technical Problem

Compressors with parallel spiral rotors face challenges in size and capacity, with small compressors lacking sufficient capacity and requiring two thrust bearings for stability, leading to increased size and cost.

Method used

A rotor assembly design that applies a preset force in a single direction to the rotors, reducing the need for two thrust bearings by balancing axial forces and allowing for a unidirectional axial force, thereby minimizing compressor size without affecting capacity.

Benefits of technology

The design achieves stable operation with reduced size and cost by applying a unidirectional axial force, eliminating the need for two thrust bearings and improving mechanical efficiency.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 0007833465000001
    Figure 0007833465000001
  • Figure 0007833465000002
    Figure 0007833465000002
  • Figure 0007833465000003
    Figure 0007833465000003
Patent Text Reader

Abstract

A compressor (200) comprising: a first rotor (20) rotatable about a first axis (11), the first rotor (20) comprising a first portion (22) and a second portion (24), and a first shaft (10) carrying the first portion (22) and the second portion (24), the first shaft (10) having a first end (12) and a second end (14) disposed on opposite sides, the first rotor (20) being configured such that a preset working force is applied to the first rotor (20) in a direction from the first end (12) to the second end (14) or from the second end (14) to the first end (12) during rotation, the size of the compressor (200) can be reduced without substantially changing the capacity of the compressor (200).
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

[0001] The present disclosure relates to the technical field of compressors, and more particularly to rotor assemblies, compressors, and air conditioners.

Background Art

[0002] A compressor generally includes a pair of parallel spiral rotors disposed within the space volume of a housing of a screw compressor. During the rotation of the pair of spiral rotors, the space volume periodically increases and decreases. As a result, the space volume is periodically connected to and closed off from an air inlet and an exhaust port to complete the intake, compression, and exhaust of air.

[0003] During the rotation of the pair of spiral rotors, two axial forces in opposite directions are formed along the rotation axes of the spiral rotors. To limit the axial forces in two directions during the rotation of the spiral rotors, two thrust bearings are disposed on the rotating shaft that supports the spiral rotors to limit the axial forces in two directions. As a result, the spiral rotors rotate relatively stably.

[0004] However, a compressor having a pair of parallel spiral rotors has a capacity associated with its size, and the size of the compressor is determined by the capacity. Since relatively small compressors often lack capacity, they may not be usable when a small and large-capacity compressor is required.

Summary of the Invention

[0005] Embodiments of the present disclosure provide a rotor assembly, a compressor, and an air conditioner that can reduce the size of a compressor without substantially changing the capacity of the compressor.

[0006] One embodiment of the present disclosure is a first rotor rotatable about a first axis and including a first portion and a second portion, a first shaft carrying the first portion and the second portion, the first shaft having a first end and a second end disposed on opposite sides, and including The present invention provides a compressor in which a preset force is applied to the first rotor during rotation in a direction from the first end toward the second end, or from the second end toward the first end.

[0007] In optional embodiments of this disclosure, the compressor is: A second rotor that is rotatable about a second axis and includes a third part that engages with the first part and a fourth part that engages with the second part, A second shaft supporting the third and fourth parts, It further includes, The first rotor and the second rotor are configured to have a preset force applied to them while they are rotating, either in a direction from the first end to the second end or from the second end to the first end.

[0008] In any optional embodiment of the present disclosure, the first part is shaped differently from the second and fourth parts, and / or The third part has a different shape from the second and fourth parts, thereby generating a pressure difference during the rotation of the first and second rotors, forming a preset force.

[0009] In optional embodiments of the present disclosure, the shape of the first, second, third, and fourth parts includes one of the following: length, number of helical blades, end face profile, density of helical blades, and diameter.

[0010] In an optional embodiment of the present disclosure, a first air supply port is provided in the first and / or third portion, and a second air supply port is provided in the second and / or fourth portion, wherein the first and second air supply ports are configured to be different from each other to create a pressure difference during the rotation of the first and second rotors in order to form a preset force.

[0011] In any optional embodiment of the present disclosure, the number of first air supply holes is different from the number of second air supply holes, and / or The size of the first air supply hole is different from the size of the second air supply hole, and / or The distance between the first air supply hole and the end face of the first part that is separated from the second part is different from the distance between the second air supply hole and the end face of the second part that is separated from the first part, or / and The distance between the first air supply hole and the end face of the third portion that is separated from the fourth portion is different from the distance between the second air supply hole and the end face of the fourth portion that is separated from the third portion.

[0012] In an optional embodiment of the present disclosure, air supply holes are provided in at least one of the first and third portions, and / or in at least one of the second and fourth portions.

[0013] In any optional embodiment of the present disclosure, a portion of the housing corresponding to the first portion has a different shape from the portions of the housing corresponding to the second and fourth portions, and / or A portion of the housing corresponding to the third part has a different shape from the portions of the housing corresponding to the second and fourth parts, thereby generating a pressure difference during the rotation of the first and second rotors, forming a preset force.

[0014] In an optional embodiment of the present disclosure, the housing is provided with a first exhaust port and a second exhaust port, wherein the length of the first exhaust port along the direction from the first end to the second end is different from the length of the second exhaust port along the direction from the second end to the first end.

[0015] In an optional embodiment of the present disclosure, a first air supply hole is provided in the housing portion corresponding to the first portion and / or the housing portion corresponding to the third portion, and a second air supply hole is provided in the housing portion corresponding to the second portion and / or the housing portion corresponding to the fourth portion. The number of the first air supply holes is different from the number of the second air supply holes, and / or The size of the first air supply hole is different from the size of the second air supply hole, and / or The distance between the first air supply hole and the end face of the first part that is separated from the second part is different from the distance between the second air supply hole and the end face of the second part that is separated from the first part, or / and The distance between the first air supply hole and the end face of the third portion that is separated from the fourth portion is different from the distance between the second air supply hole and the end face of the fourth portion that is separated from the third portion.

[0016] In an optional embodiment of the present disclosure, an air supply hole is provided in at least one of the housing portion corresponding to the first portion and the housing portion corresponding to the third portion, and / or an air supply hole is provided in at least one of the housing portion corresponding to the second portion and the housing portion corresponding to the fourth portion.

[0017] In any optional embodiment of the present disclosure, the first and second parts are arranged along the direction of gravity, the third and fourth parts are arranged along the direction of gravity, and the gravity of the first part, the second part, the third part, the fourth part, the first shaft and the second shaft imparts a preset force to the first and second rotors during their rotation, or The orientation of the first and second parts is such that it is at a narrow angle of less than 90 degrees with respect to the direction of gravity, and the orientation of the third and fourth parts is the same as the orientation of the first and second parts. Due to the force components of the first, second, third, and fourth parts, the first shaft, and the second shaft aligned with the direction of gravity, a preset force is applied to the first and second rotors during their rotation.

[0018] In an optional embodiment of the present disclosure, the compressor further includes a magnetic member configured to generate a magnetic force such that a preset force is applied to the first rotor and the second rotor while they are rotating.

[0019] In an optional embodiment of the present disclosure, the compressor further includes an oil circuit system, and the pressure of the oil circuit system acting on the first end is lower than the pressure of the oil circuit system acting on the second end. As a result, the first rotor and the second rotor are either applied with a preset acting force during rotation, or The pressure of the oil circuit system acting on the third end is lower than the pressure of the oil circuit system acting on the fourth end. As a result, the first rotor and the second rotor are applied with a preset acting force during rotation.

[0020] In an optional embodiment of the present disclosure, the compressor further includes a first thrust bearing disposed at the first end or the second end, and a preset acting force is applied to the first thrust bearing.

[0021] In an optional embodiment of the present disclosure, the first shaft is not provided with a thrust bearing, and both the first part and the second part are made of non-metallic materials.

[0022] In an optional implementation method of the present disclosure, the first shaft is not provided with a thrust bearing, a first anti-collision structure is disposed between the end of the first part away from the second part and the housing of the compressor, and a second anti-collision structure is disposed between the end of the second part away from the first part and the housing of the compressor.

[0023] In an optional embodiment of the present disclosure, the compressor further includes a first thrust bearing disposed at the first end or the second end, and a second thrust bearing disposed at the third end or the fourth end, and a preset acting force is applied to the first thrust bearing and the second thrust bearing.

[0024] In an optional embodiment of the present disclosure, the compressor A first thrust bearing located at a first end or a second end, further comprising a first thrust bearing to which a preset force is applied, The second shaft does not have a thrust bearing, and both the third and fourth parts are made of non-metallic material. The first and / or second parts are integrally formed with the first shaft, and the third and fourth parts can rotate around the second shaft.

[0025] In optional embodiments of this disclosure, the compressor is: A first thrust bearing located at a first end or a second end, further comprising a first thrust bearing to which a preset force is applied, The first shaft is not provided with a thrust bearing, the third collision prevention structure is positioned between the end of the third part that is separated from the fourth part and the compressor housing, and the fourth collision prevention structure is positioned between the end of the fourth part that is separated from the third part and the compressor housing. The first and / or second parts are integrally formed with the first shaft, and the third and fourth parts can rotate around the second shaft.

[0026] One embodiment of this disclosure is, A housing provided with a first exhaust port and a second exhaust port, A first rotor, which is rotatable within the housing around a first axis and includes a first part and a second part, A second rotor that is rotatable within the housing about a second axis and includes a third portion that engages with the first portion and a fourth portion that engages with the second portion, Includes, The first exhaust port is located at the same end of the first rotor and the second rotor, the second exhaust port is located at the same end of the first rotor and the second rotor, the first exhaust port and the second exhaust port are located at different ends of the first rotor, the first exhaust port and the second exhaust port are located at different ends of the second rotor, and the length of the first exhaust port in the direction parallel to the first axis is longer than the length of the second exhaust port in the direction parallel to the first axis.

[0027] In optional embodiments of this disclosure, the compressor is: A first shaft supporting the first and second parts, A second shaft supporting the third and fourth parts, A first thrust bearing is positioned on the first shaft and on the same side of the first or second portion, It also includes.

[0028] One embodiment of this disclosure is, Housing and A first rotor, which is rotatable within the housing around a first axis and includes a first part and a second part, A second rotor that is rotatable within the housing about a second axis and includes a third portion that engages with the first portion and a fourth portion that engages with the second portion, Includes, A first air supply hole is provided in at least one of the first part, the third part, the part of the housing corresponding to the first part, and the part of the housing corresponding to the third part, and a second air supply hole is provided in at least one of the second part, the fourth part, the part of the housing corresponding to the second part, and the part of the housing corresponding to the fourth part. The number of first air supply holes is less than the number of second air supply holes, and / or The size of the first air supply hole is smaller than the size of the second air supply hole, and / or The distance between the first air supply hole and the end face of the first part that is separated from the second part is greater than the distance between the second air supply hole and the end face of the second part that is separated from the first part.

[0029] In optional embodiments of this disclosure, the compressor is: A first shaft supporting the first and second parts, A second shaft supporting the third and fourth parts, A first thrust bearing is positioned on the first shaft and on the same side of the first or second portion, It also includes.

[0030] One embodiment of this disclosure is, Housing and A first rotor, which is rotatable within the housing around a first axis and includes a first part and a second part, A second rotor that is rotatable within the housing about a second axis and includes a third portion that engages with the first portion and a fourth portion that engages with the second portion, Includes, The first part, the third part, the portion of the housing corresponding to the first part, and the portion of the housing corresponding to the third part are all not provided with air supply holes, while at least one of the second part, the fourth part, the portion of the housing corresponding to the first part, and the portion of the housing corresponding to the fourth part is provided with air supply holes.

[0031] In optional embodiments of this disclosure, the compressor is: A first shaft supporting the first and second parts, A second shaft supporting the third and fourth parts, A first thrust bearing is positioned on the first shaft and on the same side of the first or second portion, It also includes.

[0032] One embodiment of this disclosure is, A first rotor including a first part and a second part that is rotatable about a first axis, A second rotor that is rotatable about a second axis and includes a third part that engages with the first part and a fourth part that engages with the second part, Includes, Further, a rotor assembly is provided, wherein a first air supply hole is provided in the first and / or third part, and a second air supply hole is provided in the second and / or fourth part.

[0033] The number of first air supply holes is less than the number of second air supply holes, and / or The size of the first air supply hole is smaller than the size of the second air supply hole, and / or The distance between the first air supply hole and the end face of the first part that is separated from the second part is greater than the distance between the second air supply hole and the end face of the second part that is separated from the first part.

[0034] One embodiment of this disclosure is, A first rotor including a first part and a second part that is rotatable about a first axis, A second rotor that is rotatable within the housing about a second axis and includes a third portion that engages with the first portion and a fourth portion that engages with the second portion, Includes, Further providing is a rotor assembly in which at least one of the first and third parts is provided with an air supply hole, and / or at least one of the second and fourth parts is provided with an air supply hole.

[0035] One embodiment of the present disclosure further provides a rotor assembly including a first rotor rotatable about a first axis, the first rotor including a first portion having a first air supply hole and a second portion having a second air supply hole.

[0036] The number of first air supply holes is less than the number of second air supply holes, and / or The size of the first air supply hole is smaller than the size of the second air supply hole, and / or The distance between the first air supply hole and the end face of the first part that is separated from the second part is greater than the distance between the second air supply hole and the end face of the second part that is separated from the first part.

[0037] One embodiment of the present disclosure further provides a rotor assembly comprising a first rotor rotatable about a first axis, the first rotor comprising a first portion and a second portion, at least one of the first portion and the second portion comprising an air supply hole.

[0038] One embodiment of the present disclosure includes a compressor according to any one of the above embodiments, or Further, an air conditioner is provided that includes a rotor assembly according to any one of the above embodiments.

[0039] In embodiments of the present disclosure, the first and second portions of a first rotor supported by a first shaft can rotate around the first shaft, and a preset force can be applied to the first rotor in a single direction during its rotation. For example, during the rotation of the first rotor, a preset force is applied to the first rotor in a direction from the first end toward the second end. In another example, during the rotation of the first rotor, a preset force is applied to the first rotor in a direction from the second end toward the first end. Embodiments of the present disclosure can realize that a compressor is subjected to a unidirectional axial force during operation, and then the specific direction of the unidirectional axial force can be determined during the operation of the compressor, and as a result, relevant measures can be taken to limit the unidirectional axial force without restricting the direction in which the axial force is not applied. Compared to the prior art, if the axial force is not determined or is applied to two ends, embodiments of the present disclosure only need to limit the axial force toward one end, instead of restricting both ends of the first shaft. Therefore, embodiments of the present disclosure can reduce the size of the compressor without substantially affecting the compressor capacity and without substantially affecting the compressor stability.

[0040] In one embodiment of the present disclosure, the first rotor can engage with another rotor structure, such as a second rotor, during rotation, with a first portion of the first rotor engaging with a third portion of the second rotor, and a second portion of the first rotor engaging with a fourth portion of the second rotor, thus forming two rotor pairs. Compared to the prior art, the embodiment of the present disclosure provides engagement between the first and second rotors, which is equivalent to a parallel connection of two screw compressors. Therefore, compared to a screw compressor of the prior art, the compressor of the embodiment of the present disclosure can be significantly reduced in size for the same or similar capacity. Combined with the embodiment of the present disclosure, the compressor can achieve a single directional axial force during the rotation of the first and second rotors by a preset force. If the capacity of the compressor in the embodiment of the present disclosure is essentially the same as that of an existing screw compressor, the embodiment of the present disclosure can be limited to operating one rotor using one thrust bearing, compared to the prior art which uses two thrust bearings to limit one rotor structure, in order to further reduce the size of the compressor.

[0041] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the drawings that may be used in the description of the embodiments are briefly described below. Obviously, the drawings used in the following description are only a few embodiments of this disclosure. Those skilled in the art can obtain other drawings by following these without any creative effort.

[0042] To better understand this disclosure and its beneficial effects, the following description is made in conjunction with the accompanying drawings, and the same reference numerals in the following description represent the same parts. [Brief explanation of the drawing]

[0043] [Figure 1] This is a schematic diagram of a part of a compressor according to the first embodiment of the present disclosure. [Figure 2] This is a schematic diagram illustrating the cooperation of a first rotor, a second rotor, a first shaft, and a second shaft of a compressor according to one embodiment of the present disclosure. [Figure 3] This is a schematic diagram of a part of a compressor according to a second embodiment of the present disclosure. [Figure 4] This is a schematic diagram of a part of a compressor according to a third embodiment of the present disclosure. [Figure 5] This is a schematic diagram of a part of a compressor according to the fourth embodiment of this disclosure. [Figure 6] This is a schematic diagram of a part of a compressor according to the fifth embodiment of this disclosure. [Figure 7] This is a schematic diagram of a part of a compressor according to the sixth embodiment of this disclosure. [Figure 8] This is a schematic diagram of a part of a compressor according to the seventh embodiment of this disclosure. [Figure 9] This is a schematic diagram of a part of a compressor according to the eighth embodiment of this disclosure. [Figure 10] This is a schematic diagram of a part of a compressor according to the ninth embodiment of this disclosure. [Figure 11] This is a schematic diagram of a part of a compressor according to the tenth embodiment of this disclosure. [Figure 12] This is a schematic diagram of a part of a compressor according to the eleventh embodiment of this disclosure. [Modes for carrying out the invention]

[0044] The technical solutions in the embodiments of this disclosure are described below clearly and completely with reference to the accompanying drawings in the embodiments of this disclosure. Obviously, the embodiments described herein are only a selection, and not all, of the embodiments of this disclosure. The following description of at least one example is merely illustrative and in no way a limitation to this disclosure and its use or application. All other embodiments that can be obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of this disclosure.

[0045] References to “embodiments” or “implementations” in this specification mean that certain features, structures, or characteristics described in relation to embodiments or implementations may be included in at least one embodiment of this disclosure. The appearance of phrases in various parts of the description does not necessarily refer to the same embodiment, or to mutually exclusive, independent, or alternative embodiments with respect to other embodiments. Those skilled in the art will understand, both explicitly and implicitly, that the embodiments described herein can be combined with other embodiments.

[0046] Embodiments of this disclosure provide a rotor assembly, a compressor, and an air conditioner.

[0047] Referring to Figure 1, a schematic diagram of a part of a compressor according to a first embodiment of the present disclosure is shown. As shown in Figure 1, the compressor 200 may be a screw compressor. For example, the compressor 200 is an opposed screw compressor. Note that the compressor 200 shown in Figure 1 is not limited to a screw compressor. For example, the compressor 200 may also be a scroll compressor. The compressor 200 includes a first shaft 10, a first rotor 20, a second shaft 30, a second rotor 40, a first thrust bearing 50, and a housing 60. The housing 60 may house the first rotor 20 and the second rotor 40, and the housing 60 may house a part of the first shaft 10 and a part of the second shaft 30.

[0048] The housing 60 has a housing space that accommodates a first rotor 20, a second rotor 40, a portion of a first shaft 10, and a portion of a second shaft 30. The housing 60 further has a first exhaust port 201, a second exhaust port 201, and an intake port 203 that communicate with the housing space that accommodates the first rotor 20, the second rotor 40, a portion of the first shaft 10, and a portion of the second shaft 30. The intake port 203 is configured to send air from outside the housing 60 into the housing space within the housing 60 when the first rotor 20 and the second rotor 40 engage with each other and rotate together, and the first exhaust port 201 and the second exhaust port 202 are configured to compress the air in the housing space of the housing 60 to the outside of the housing 60 when the first rotor 20 and the second rotor 40 engage with each other and rotate together. In this way, the processes of air intake, compression, and exhaust of the compressor 200 can be realized. The first exhaust port 201 and the second exhaust port 202 are located at both ends of the housing 60 along the direction of the first axis 11 of the first shaft 10. The intake port 203 is located in the center of the housing 60 along the direction of the first axis 11 of the first shaft 10.

[0049] Please note that terms such as “first,” “second,” etc., in the description and claims of this disclosure are used to distinguish different subjects, not to indicate a specific order. Furthermore, the terms “including” and “having,” and any variations thereof, are intended to encompass non-exclusive inclusion.

[0050] The first rotor 20 and the second rotor 40 are engaged with each other. In embodiments of this disclosure, the first rotor 20 may be a male rotor and the second rotor 40 may be a female rotor. In other embodiments of this disclosure, the first rotor 20 may be a female rotor and the second rotor 40 may be a male rotor. Hereinafter, embodiments of this disclosure will be described in detail, using the first rotor 20 as a male rotor and the second rotor 40 as a female rotor as an example.

[0051] The first rotor 20, as a male rotor, can be understood as a driving rotor, and the second rotor 40, as a female rotor, can be understood as a driven rotor. For example, the first rotor 20 may be drivably connected to a drive assembly such as an electric motor (including, but not limited to, a permanent magnet motor). The first rotor 20 can be driven to rotate by the drive assembly, and as the first rotor 20 rotates, the second rotor 40 is driven to rotate together with it.

[0052] The first rotor 20 is supported by the first shaft 10 and is drivably connected to a drive assembly via the first shaft 10. The drive assembly can drive the first shaft 10 to rotate, and the first shaft 10 can rotate together with the first rotor 20 supported by the first shaft 10 about the first axis 11 of the first shaft 10. That is, the first rotor 20 is rotatable about the first axis 11 within the housing 60. In embodiments of the present disclosure, the first rotor 20 may be formed integrally with the first shaft 10. In other embodiments of the present disclosure, a portion of the first rotor 20 may be formed integrally with the first shaft 10, and a portion of the first rotor 20 may be fitted onto the first shaft 10. In other embodiments of the present disclosure, the first rotor 20 may be directly fitted onto the first shaft 10.

[0053] In one example, the first rotor 20 may have at least two parts. For example, the first rotor 20 may have a first part 22 and a second part 24, both of which may be integrally formed with the first shaft 10. One of the first part 22 and the second part 24, for example the first part 22, can be integrally formed with the first shaft 10, while the other, for example the second part 24, is fitted onto the first shaft 10. Both the first part 22 and the second part 24 are fitted onto the first shaft 10.

[0054] Referring to Figure 2, Figure 2 is a schematic diagram of the cooperation of a first rotor, a second rotor, a first shaft, and a second shaft of a compressor according to one embodiment of the present disclosure. The first portion 22 of the first rotor 20 can be formed integrally with the first shaft 10, and the second portion 24 is fitted onto the first shaft 10 adjacent to the first portion 22. In embodiments of the present disclosure, adjacent end faces of the first portion 22 and the second portion 24 can be attached to each other. In other embodiments of the present disclosure, adjacent end faces of the first portion 22 and the second portion 24 may also not be attached to each other and may have a small gap between them, such as 0.1 mm, 0.2 mm, or 0.3 mm.

[0055] Referring again to Figures 1 and 2, the first rotor 20 has helical blades, also called male blades. The first rotor 20 includes a first helical blade 222 located in the first portion 22 and a second helical blade 242 located in the second portion 24. There may be multiple first helical blades 222 and multiple second helical blades 242. In embodiments of the present disclosure, the first helical blades 222 and the second helical blades 242 are configured to have opposite helical directions, that is, the rotation directions of the first portion 22 and the second portion 24 are opposite. When the first rotor 20 and the second rotor 40 engage with each other and rotate together, opposite axial forces are generated between the first helical blades 222 and the second helical blades 242, which can also be understood as the generation of opposite axial flows between the first helical blades 222 and the second helical blades 242. Due to the symmetry of the axial forces, the opposing axial forces generated between the first helical vane 222 and the second helical vane 242 can be nearly balanced.

[0056] In the descriptions of this disclosure, "plurality" means two or more unless otherwise specified.

[0057] Referring again to Figures 1 and 2, the second rotor 40 is supported by the second shaft 30, which is configured to rotatably support the second rotor 40, and the second rotor 40 can rotate relative to the second shaft 30. The second rotor 40 engages with the first rotor 20 and is driven by the first rotor 20 to rotate on the second shaft 30 about the second axis 31 of the second shaft 30. The second rotor 40 may have at least two parts. For example, the second rotor 40 has a third part 42 and a fourth part 44, both of which are fitted onto the second shaft 30. Both the third part 42 and the fourth part 44 are rotatable within the housing 60 about the second axis 31.

[0058] The third portion 42 engages with the first portion 22, and the fourth portion 44 engages with the second portion 24. The rotation direction of the third portion 42 is opposite to that of the first portion 22, and the rotation direction of the fourth portion 44 is opposite to that of the second portion 24.

[0059] The second rotor 40 has helical blades, also called female blades. The second rotor 40 includes a third helical blade 422 located in the third portion 42 and a fourth helical blade 442 located in the fourth portion 44. There may be multiple third helical blades 422 and multiple fourth helical blades 442. In embodiments of the present disclosure, the third helical blade 422 and the fourth helical blade 442 are configured to have opposite helical directions, i.e., the rotation directions of the third portion 42 and the fourth portion 44 are opposite. When the first rotor 20 and the fourth rotor 40 engage with each other and rotate together, opposite axial forces are generated between the first helical blade 422 and the fourth helical blade 442, which can also be understood as the generation of opposite axial flows between the third helical blade 422 and the fourth helical blade 442. Due to the symmetry of the axial forces, the opposing axial forces generated between the third helical vane 422 and the fourth helical vane 442 can be nearly balanced.

[0060] The second shaft 30 can support the third portion 42 and the fourth portion 44 via one or more transmission assemblies 80. For example, the third portion 42 is fitted onto the first transmission member 82 in the transmission assembly 80, and the fourth portion 44 is fitted onto the second transmission member 84 in the transmission assembly 80. The first transmission member 82 and the second transmission member 84 may be sliding bearings or rolling bearings.

[0061] Referring again to Figure 1, the first shaft 10 has a first end 12 and a second end 14, and the first portion 22 and second portion 24 of the first rotor 20 are positioned between the first end 12 and the second end 14. The second shaft 30 has a third end 32 and a fourth end 34, with the third portion 42 and fourth portion 44 of the second rotor 40 enclosed between them. The first portion 22 has a first exhaust end face 223 located at the first exhaust port 201 and a first intake end face (not shown) located at the intake port 203, and the second portion 24 has a second exhaust end face 243 located at the second exhaust port 202 and a second intake end face located at the intake port 203 (not shown). The first intake end face is adjacent to the second intake end face, and in embodiments of this disclosure, the first intake end face and the second intake end face may or may not be attached to each other. In one embodiment of this disclosure, the first shaft 10 may be parallel to the second shaft 30, and the first axis 11 of the first shaft 10 may be parallel to the second axis 31 of the second shaft 30.

[0062] The third portion 42 has a third exhaust end face 423 located at the first exhaust port 201 and a third intake end face (not shown) located at the intake port 203, and the fourth portion 44 has a fourth exhaust end face 443 located at the second exhaust port 202 and a fourth intake end face located at the intake port 203 (not shown). The first intake end face is adjacent to the second intake end face, and in embodiments of the present disclosure, the first intake end face and the second intake end face are spaced apart from each other to ensure that the first portion 22 and the fourth portion 44, and the second portion 24 and the third portion 42 do not interfere with each other.

[0063] The housing 60 has a fifth exhaust end face (not shown) located at the first exhaust port 201 and a sixth exhaust end face (not shown) located at the second exhaust port. The fifth exhaust end face may be spaced at a distance less than a first preset value from the first exhaust end face 223 and the third exhaust end face 423, so that the fifth exhaust end face, the first exhaust end face 223 and the third exhaust end face 423 are always spaced apart from each other and do not easily collide with each other. The sixth exhaust end face may be spaced at a distance less than a first preset value from the second exhaust end face 243 and the fourth exhaust end face 443, so that the fifth exhaust end face, the first exhaust end face 223 and the third exhaust end face 423 are always spaced apart from each other and do not easily collide with each other.

[0064] The first thrust bearing 50 is located on the first shaft 10, for example, on the second end 14 of the first shaft 10. In some other embodiments of the present disclosure, the first thrust bearing 60 is located on the first end 12.

[0065] With respect to the first rotor 20 and the second rotor 40, when the first rotor 20 and the second rotor 40 engage with each other and rotate together, the opposite rotational directions of the first portion 22 and the second portion 24 can generate opposite axial forces, and the opposite rotational directions of the third portion 42 and the fourth portion 44 can generate opposite axial forces. Therefore, the axial forces between the first portion 22 and the second portion 24 can be balanced to some extent, and the axial forces between the third portion 42 and the fourth portion 44 can be balanced to some extent.

[0066] However, it should be noted that in actual production and processing processes, on the one hand, there are some differences in the structure of different parts of the first rotor 20 due to manufacturing deviations, and on the other hand, there are some differences in the structure of different parts of the second rotor 40. Furthermore, there are also differences between the first rotor 20 and the second rotor 40. On the other hand, there are some differences in the assembly of the first rotor 20 and the second rotor 40 due to tolerance and misalignment issues in assembly. As a result, the axial forces between the first part 22 and the second part 24 cannot be perfectly balanced, and the axial forces between the third part 42 and the fourth part 44 cannot be perfectly balanced. When the first rotor 20 and the second rotor 40 engage with each other and rotate together, it is not possible to almost perfectly balance the axial forces and form a resultant force of axial forces in a random direction. The combined axial force may be directed in the first direction H1, and the resultant force may also be directed in the second direction H2.

[0067] On the other hand, in the quantification of compressor products, the direction of the composite axial force generated by the rotor of each compressor differs depending on the differences in the rotors of each compressor. For example, in some compressors, the direction of the composite axial force of the rotor is directed in a first direction H1, and in some compressors, the direction of the composite axial force of the rotor is directed in a second direction H2. In other words, a random axial force and a random resultant force appear throughout the rotor shaft system, causing the entire shaft system to be randomly pushed towards one of the two exhaust end faces, and the exhaust end face of the rotor on that side comes into contact with the end face of the housing, causing friction and failure.

[0068] In conventional technology, to ensure the stable operation of all formed compressors, two sets of thrust bearings (also called axial force bearings) are fitted onto each shaft of the compressor to provide positional constraints on the resultant axial force of the rotors of all formed compressors, and thus ensure the stable operation of all formed compressors.

[0069] Therefore, the use of thrust bearings for bearing and positional limiting remains unavoidable, and due to the randomness of the resultant force direction, thrust bearings must satisfy the requirements for two-way bearing and positional limiting. That is, in the actual production and manufacturing processes of compressors, thrust bearings (axial force bearings) are still required for limiting two directions on a single rotating shaft in order to ensure that the resultant force of the rotor's axial force is limited. For example, a compressor is equipped with two sets of thrust bearings with opposite bearing directions so that the resultant force of axial forces in two random directions is reliably supported. However, in the case of independent individual compressors, the direction of the randomly occurring resultant axial force is always the same. In this case, one set of thrust bearings is used for positional limiting, and the other set of thrust bearings is completely idle, thereby resulting in lower performance, extra mechanical losses and lubrication requirements, and an increased failure rate of the compressor. This ultimately leads to an increase in the size and cost of the compressor assembly, reduces the mechanical efficiency of the axial system operation to some extent, and increases the lubrication requirements.

[0070] Based on this, embodiments of the present disclosure ensure that when the first rotor 20 and the second rotor 40 of the compressor 200 engage with each other and rotate together, the first rotor 20 and the second rotor 40 are subjected to a combined axial force in a determined single axial direction. Therefore, in embodiments of the present disclosure, to achieve limitation to the combined axial force in a determined single axial direction, only the first thrust bearing 50 needs to be placed on one shaft, such as the first shaft 10, thereby ensuring that the first rotor 20 and the second rotor 40 of the compressor 200 of embodiments of the present disclosure can rotate reliably and stably without causing contact and friction between the exhaust end faces of the rotors and the end faces of the housing. Compared to the prior art which requires two thrust bearings to be fixed on one shaft, the compressor of embodiments of the present disclosure can avoid the use of multiple thrust bearings and reduce the overall size and cost of the compressor. Furthermore, the reduction in the number of thrust bearings can improve the efficiency of the axial system operation to some extent and reduce the requirement for lubricating oil.

[0071] In some embodiments of the present disclosure, the internal structure of the compressor 200 is designed to have a predetermined difference in the production and processing process of the compressor 200 so that the compressor 20 can reliably generate a resultant force of axial forces in a determined specific direction between the first rotor 20 and the second rotor 40. For example, in embodiments of the present disclosure, the compressor 200 can form a pressure difference in a predetermined direction by a difference in the hole and slot structure.

[0072] Next, we will describe the shape of the compressor 200 used to house the first rotor 20 and the second rotor 40, and the shape difference between the first rotor 20 and the second rotor 40 that causes the formation of a pressure difference.

[0073] In embodiments of this disclosure, during the rotation of the first rotor 20 and the second rotor 40, only a predetermined and single-direction preset force is applied to the first thrust bearing 50. The direction of the preset force may be a preset force from the second end 14 toward the first end 12. The direction from the second end 14 toward the first end 12 may be defined as the second direction H2, and the direction from the first end 12 toward the second end 14 may be defined as the first direction H1. The preset force can be understood as a combined axial force formed when the first rotor 20 and the second rotor 40 engage with each other and rotate together. During the rotation of the first rotor 20 and the second rotor 40, the axial forces of the first rotor 20 and the second rotor 40 along the first direction H1 are smaller than the axial forces of the first rotor 20 and the second rotor 40 along the second direction H2, and form the preset force applied to the first thrust bearing 50.

[0074] In embodiments of the present disclosure, the shapes of the first portion 22 and the third portion 42 are different from the shapes of the second portion 24 and the fourth portion 44 in order to generate a pressure difference during the rotation of the first rotor 20 and the second rotor 40 and to form a preset force applied to the first thrust bearing 50. It can be understood that the shape of the first portion 22 is different from the shapes of the second portion 24 and the fourth portion 44, and / or the shape of the third portion 42 is different from the shapes of the second portion 24 and the fourth portion 44, in order to generate a pressure difference during the rotation of the first rotor 20 and the second rotor 40 and to form a preset force.

[0075] If the shapes of the first part 22 and the third part 42 are different from the shapes of the second part 24 and the fourth part 44, then the shape of the first part 22 is different from the shape of the second part 24, the shape of the third part 42 is different from the shape of the fourth part 44, the shape of the first part 22 is different from the shape of the second part 24, and the shape of the third part 42 is the same as the shape of the fourth part 44, the shape of the first part 22 is the same as the shape of the second part 24, and the shape of the third part 42 is different from the shape of the fourth part 44, the shape of the first part 22 is different from the shape of the fourth part 44, and the shape of the third part 42 is different from the shape of the fourth part 44 This includes, but is not limited to, the following: the shape of the first part 22 is the same as the shape of the fourth part 44, the shape of the third part 42 is different from the shape of the fourth part 44, the shape of the first part 22 is different from the shape of the fourth part 44, the shape of the third part 42 is the same as the shape of the second part 24, the shape of the first part 22 is different from the shape of the fourth part 44, the shape of the third part 42 is different from the shape of the second part 24, the shape of the first part 22 is the same as the shape of the fourth part 44, the shape of the third part 42 is different from the shape of the second part 24, the shape of the first part 22 is different from the shape of the fourth part 44, and the shape of the third part 42 is the same as the shape of the fourth part 44.

[0076] Referring to Figure 3, a schematic diagram of a portion of a compressor according to a second embodiment of the present disclosure is shown. In some embodiments, if the shapes of the first portion 22 and the third portion 42 differ from the shapes of the second portion 24 and the fourth portion 44, the shapes of the first portion 22, the second portion 24, the third portion 42 and the fourth portion 44 include, but are not limited to, length, number of helical blades, end face profile, density of helical blades, and diameter. If the shapes of the first portion 22 and the third portion 42 differ from the shapes of the second portion 24 and the fourth portion 44, it is understood that the shapes of the first portion 22, the second portion 24, the third portion 42 and the fourth portion 44 include, but are not limited to, length, number of helical blades, end face profile, density of helical blades, and diameter.

[0077] The length L5 of the first portion 22 of the first rotor 20 in the compressor 200 shown in Figure 3, along the first axial direction, is different from the length L6 of the second portion 24 along the first axial direction. For example, the length L5 of the first portion 22 along the first axis 11 direction is shorter than the length L6 of the second portion 24 along the first axis 11 direction. In some optional embodiments, the number of helical blades 242 of the second portion 24 is greater than the number of helical blades 222 of the first portion 22.

[0078] During the operation of the compressor 200, both the first part 22 and the second part 24 rotate around the first shaft 11. Since the length of the second part 24 along the direction of the first shaft 11 is longer than the length L5 of the first part 22 along the direction of the first shaft 11, the first rotor 20 forms a combined axial force in the second direction H2 during rotation, thereby realizing the direction of the axial force.

[0079] Furthermore, the method of achieving the direction of axial force through the different shapes of the first portion 22 and the second portion 24 is not limited to, for example, having different diameters of the first portion 22 and the second portion 24, different densities of the helical blades 222 of the first portion 22 and the helical blades 242 of the second portion 24, different thicknesses of the helical blades 222 of the first portion 22 and the helical blades 242 of the second portion 24, and different end face profiles of the first portion 22 and the second portion 24.

[0080] In embodiments of the present disclosure, a first air supply hole 221 is provided in at least one of the first portion 22 and the third portion 42, and / or a second air supply hole 241 is provided in at least one of the second portion 24 and the fourth portion 44. The first air supply holes 221 and the second air supply holes 241 are configured to be different from each other to create a pressure difference during the rotation of the first rotor 20 and the second rotor 40 in order to form a preset force applied to the first thrust bearing 50. There may be one or more first air supply holes 221 and one or more second air supply holes 241.

[0081] In an optional embodiment of this disclosure, referring to Figure 1, the number of first air supply holes 221 is less than the number of second air supply holes 241. For example, there are three first air supply holes 221 and five second air supply holes 241. During the air supply process, the amount of air supplied to the second section 24 and the fourth section 44 is greater than the amount of air supplied to the first section 22 and the third section 42. While the first rotor 20 and the second rotor 40 are rotating, the air pressure formed by the first section 22 and the third section 42 is less than the air pressure formed by the second section 24 and the fourth section 44. Therefore, the pressure difference between the first rotor 20 and the second rotor 40 is applied to the first thrust bearing 50 along the second direction H2. Embodiments of this disclosure are suitable for models in which economizer air supply is turned on under all operating conditions, as it is easiest to achieve the direction of the axial force and change the number of air supply holes formed.

[0082] In an optional embodiment of this disclosure, with reference to Figure 4, a schematic diagram of a portion of a compressor according to a third embodiment of this disclosure is shown. The distance between the first air supply port 221 and the end face of the first portion 22 away from the second portion 24 is greater than the distance between the second air supply port 241 and the end face of the second portion 24 away from the first portion 22. That is, the distance L1 between the first air supply port 221 and the first exhaust end face 223 is greater than the distance L2 between the second air supply port 241 and the second exhaust end face 243. In some other embodiments, the distance between the first air supply port 221 and the end face of the third portion 42 away from the fourth portion 44 is greater than the distance between the second air supply port 241 and the end face of the fourth portion 44 away from the third portion 42. That is, the distance between the first air supply port 221 and the third exhaust end face 423 is greater than the distance between the second air supply port 241 and the second exhaust end face 243. During the air supply process, the second section 24 and the fourth section 44 may be supplied with air earlier than the first section 22 and the third section 42. While the first rotor 20 and the second rotor 40 are rotating, the air pressure formed by the first section 22 and the third section 42 is less than the air pressure formed by the second section 24 and the fourth section 44. Therefore, the pressure difference between the first rotor 20 and the second rotor 40 is applied to the first thrust bearing 50 along the second direction H2. Since the axial position of each air supply hole can be easily changed in the embodiments of this disclosure, this disclosure is suitable for models in which the economizer air supply is turned on under all operating conditions.

[0083] In an optional embodiment of this disclosure, with reference to Figure 5, a schematic diagram of a portion of a compressor according to a fourth embodiment of this disclosure is shown. The size of the first air supply port 221 is smaller than the size of the second air supply port 241. During the air supply process, the amount of air supplied by the second portion 24 and the fourth portion 44 is greater than the amount of air supplied by the first portion 22 and the third portion 42. While the first rotor 20 and the second rotor 40 are rotating, the air pressure formed by the first portion 22 and the third portion 42 is less than the air pressure formed by the second portion 24 and the fourth portion 44. Therefore, the pressure difference between the first rotor 20 and the second rotor 40 is applied to the first thrust bearing 50 along the second direction H2.

[0084] In an optional embodiment of the present disclosure, referring to Figures 1, 4, and 5, the first air supply hole 221 is formed in the first portion 22, and the second air supply hole 241 is formed in the second portion 24.

[0085] In an optional embodiment of the present disclosure, the first air supply hole 221 is formed in the first portion 22, and the second air supply hole 241 is formed in the fourth portion 44.

[0086] In an optional embodiment of this disclosure, with reference to Figure 6, a schematic diagram of a part of a compressor according to a fifth embodiment of this disclosure is shown. A third portion 42 is formed in the third air supply port 421, and a second portion 24 is formed in the second air supply port 241. The third air supply port 421 formed in the third portion 42 can be understood as the first air supply port.

[0087] In an optional embodiment of the present disclosure, the first air supply hole is formed in the third portion 42, and the second air supply hole is formed in the fourth portion 44.

[0088] In an optional embodiment of the present disclosure, the first air supply holes 221 are formed in the first portion 22, and the second air supply holes are formed in the second portion 24 and the fourth portion 44.

[0089] In an optional embodiment of the present disclosure, the first air supply hole 221 is formed in the third portion 42, and the second air supply holes are formed in the second portion 24 and the fourth portion 44.

[0090] In an optional embodiment of the present disclosure, the first air supply holes are formed in the first portion 22 and the third portion 42, and the second air supply holes 241 are formed in the second portion 24.

[0091] In an optional embodiment of the present disclosure, the first air supply holes are formed in the first portion 22 and the third portion 42, and the second air supply holes are formed in the fourth portion 44.

[0092] In an optional embodiment of the present disclosure, air supply holes are provided in at least one of the first portion 22 and the third portion 42, and / or air supply holes are provided in at least one of the second portion 24 and the fourth portion 42.

[0093] In an optional embodiment of the present disclosure, with reference to Figure 7, a schematic diagram of a portion of a compressor according to a sixth embodiment of the present disclosure is shown. At least one of the first portion 22 and the third portion 42 is provided with an optional air supply hole, and at least one of the second portion 24 and the fourth portion 44 is provided with an air supply hole, such as a second air supply hole 241. During the air supply process, air may be supplied to the second portion 24 and the fourth portion 44, but not to the first portion 22 and the third portion 42. While the first rotor 20 and the second rotor 40 are rotating, the air pressure formed by the first portion 22 and the third portion 42 is less than the air pressure formed by the second portion 24 and the fourth portion 44. Therefore, the pressure difference between the first rotor 20 and the second rotor 40 is applied to the first thrust bearing 50 along the second direction H2.

[0094] In optional embodiments of the present disclosure, the shapes of the housing portions corresponding to the first portion 22 and the third portion 42 differ from the shapes of the housing portions corresponding to the second portion 24 and the fourth portion 44 in order to generate a pressure difference during the rotation of the first rotor 20 and the second rotor 40 and to form a preset force applied to the first thrust bearing 50.

[0095] In an optional embodiment of this disclosure, with reference to Figure 8, a schematic diagram of a part of a compressor according to a seventh embodiment of this disclosure is shown. A fourth air supply port 62 is provided in the housing portion corresponding to the first portion 22 and the third portion 42, and a fifth air supply port 64 is provided in the housing portion corresponding to the second portion 24 and the fourth portion 44. The fourth air supply port 62 can be understood as the first air supply port, and the fifth air supply port 64 can be understood as the second air supply port. The relationship between the fourth air supply port 62 and the fifth air supply port 64 can refer to the relationship between the first air supply port 221 and the second air supply port 241, and this will not be repeated here.

[0096] In an optional embodiment of the present disclosure, the portions of the housing corresponding to the first portion 22 and the third portion 42 are not provided with air supply holes, while the portions of the housing corresponding to the second portion 24 and the fourth portion 44 are provided with air supply holes such as a fifth air supply hole 64.

[0097] In an optional embodiment of this disclosure, with reference to Figure 9, a schematic diagram of a portion of a compressor according to an eighth embodiment of this disclosure is shown. The length L3 of the first exhaust port 201 along the direction from the first end 12 to the second end 14 is greater than the length L4 of the second exhaust port 202 along the direction from the second end 14 to the first end 12. That is, the length of the first exhaust port 201 along the first direction H1 is greater than the length of the second exhaust port 202 along the first direction H1. During the exhaust process, the capacity of the first exhaust port 201 is greater than the capacity of the second exhaust port 202. During the rotation of the first rotor 20 and the second rotor 40, the air pressure formed by the first portion 22 and the third portion 42 is less than the air pressure formed by the second portion 24 and the fourth portion 44. Thus, the pressure difference between the first rotor 20 and the second rotor 40 is applied to the first thrust bearing 50 along the second direction H2.

[0098] In embodiments of the present disclosure, the shapes of the housing portions corresponding to the first portion 22 and the third portion 42 may differ from the shapes of the housing portions corresponding to the second portion 24 and the fourth portion 44 in order to increase the pressure difference between the first portion 22 and the third portion 42 and to ensure the operational stability of the compressor 200, and the shapes of the first portion 22 and the third portion 42 may differ from the shapes of the second portion 24 and the fourth portion 44 in order to generate a sufficient pressure difference during the rotation of the first rotor 20 and the second rotor 40 to form a preset force applied to the first thrust bearing 50. When the shapes of the housing portions corresponding to the first portion 22 and the third portion 42 differ from the shapes of the housing portions corresponding to the second portion 24 and the fourth portion 44, refer to the above disclosures, which are not repeated here. When the shapes of the first portion 22 and the third portion 42 differ from the shapes of the second portion 24 and the fourth portion 44, refer to the above disclosures, which are not repeated here. Embodiments of this disclosure achieve a small difference in the direction of the axial force and between the exhaust ports on both sides, ensuring reliable operation of the compressor 200 regardless of whether air is being supplied to the compressor 200.

[0099] In an optional embodiment of the present disclosure, during the rotation of the first rotor 20 and the second rotor 40, the axial forces of the first rotor 20 and the second rotor 40 along the direction from the first end 12 to the second end 14 are greater than the axial forces along the direction from the second end 14 to the first end 12, forming a preset force applied to the first thrust bearing 50. That is, the axial forces of the first rotor 20 and the second rotor 40 along the first direction H1 are greater than the axial forces of the first rotor 20 and the second rotor 40 along the second direction H2, forming a preset force applied to the first thrust bearing 50.

[0100] In optional embodiments of this disclosure, the direction of the axial forces of the first rotor 20 and the second rotor 40 can be achieved under the action of a preset force. The first shaft 10 may be provided with a thrust bearing such as a first thrust bearing 50, while the second shaft 30 may not be provided with a thrust bearing. The second rotor 40 can withstand contact and friction between the exhaust end face of the second rotor and the exhaust end face of the housing 60 without being damaged in the direction of the axial force. For example, the second rotor 40 is made of a non-metallic material such as Peek material. That is, the third part 42 and the fourth part 44 are not made of a non-metallic material such as Peek material. In another example, a collision prevention structure such as a copper ring is placed between the second rotor 40 and the housing 60. Specifically, a first collision prevention structure is positioned between the end of the third portion 42, which is separated from the fourth portion 44, and the housing 60 of the compressor 200, and a second collision prevention structure is positioned between the end of the fourth portion 44, which is separated from the third portion 42, and the housing 60 of the compressor 200. It should also be noted that the first portion 22 and / or the second portion 24 are integrally formed with the first shaft 10, and the third portion 42 and the fourth portion 44 can rotate around the second shaft 30. The second shaft 30 is fixed to the housing 60 and does not rotate.

[0101] In optional embodiments of this disclosure, the direction of the axial force of the first rotor 20 and the second rotor 40 can be achieved under the action of a preset force. The first shaft 10 is not provided with a thrust bearing, and the second shaft 30 is not provided with a thrust bearing. Both the first rotor 20 and the second rotor 40 can withstand contact and friction between the exhaust end face of the second rotor and the exhaust end face of the housing 60 without being damaged in the direction of the axial force. For example, both the first rotor 20 and the second rotor 40 are made of a non-metallic material such as Peek material. In another example, collision prevention structures such as copper rings are placed between the first rotor 20 and the housing 60 and between the second rotor 40 and the housing 60, respectively.

[0102] Referring to Figure 10, a schematic diagram of a part of a compressor according to the ninth embodiment of this disclosure is shown. The difference between the compressor 200 shown in Figure 10 and the compressors 200 shown in Figures 1, 2, and 4 to 8 is that the second shaft 30 of the compressor 200 shown in Figure 10 does not have an axial thrust bearing. To prevent the second rotor 40 from being easily damaged when it comes into contact with the housing 60, the second rotor 40 can be made of a non-metallic material such as Peek material, or a collision prevention structure such as a copper ring can be placed between the second rotor 40 and the housing 60.

[0103] Referring again to Figures 1, 2, and 4-9, in an optional embodiment of the present disclosure, the compressor 200 may further include a second thrust bearing, the second thrust bearing 70 located on the second shaft 30, for example, on the fourth end 34 of the second shaft 30. In some other embodiments of the present disclosure, the second thrust bearing 70 is located on the third end 32. During the rotation of the first rotor 20 and the second rotor 40, only predetermined and single-direction preset forces are applied to the first thrust bearing 50 and the second thrust bearing 70. Therefore, in the embodiments of the present disclosure, in order to achieve a limit on a predetermined single axial composite force, it is sufficient to place the first thrust bearing 50 on one shaft, such as the first shaft 10, and the second thrust bearing 70 on the second shaft 30, thereby enabling the first rotor 20 and the second rotor 40 of the compressor 200 of the embodiments of the present disclosure to rotate reliably and stably without causing contact and friction between the exhaust end faces of the rotors and the end faces of the housing. Compared with the prior art which requires two thrust bearings to be fixed on one shaft, the compressor of the embodiments of the present disclosure can reduce the size and cost of the two thrust bearings and the compressor as a whole. Furthermore, the reduction in the number of thrust bearings can improve the efficiency of the axial system operation to some extent and reduce the requirement for lubricating oil.

[0104] In optional embodiments of this disclosure, the axial force directions of the first rotor 20 and the second rotor 40 can be achieved under the action of a preset force. The first shaft 10 may be provided with a thrust bearing, such as a first thrust bearing 50. The second shaft 30 may be provided with two thrust bearings, one of which may be a second thrust bearing 70. Compared to the prior art, embodiments of this disclosure can reduce the number of thrust bearings required for a compressor having two rotors by one.

[0105] In some other embodiments of this disclosure, the compressor 200 may be provided with a structure for generating additional forces that act on the first rotor 20 and the second rotor 40 when they are engaged with each other and rotating together, such that a composite axial force in a predetermined specific direction is generated between the first rotor 20 and the second rotor 40. The external force may be one of the following: electromagnetic, gravity, hydraulic, etc. In embodiments, the shapes of the first part 22 and the second part 24 may be the same or different. The shapes of the third part 42 and the fourth part 44 may be the same or different. Next, the direction of the axial force on the first rotor 20 and the second rotor 40 driven by the external force will be described.

[0106] Referring to Figure 11, a schematic diagram of a portion of a compressor according to a tenth embodiment of the present disclosure is shown. The compressor 200 shown in Figure 11 further includes a drive motor 90. The drive motor 90 includes a motor rotor 92 and a motor stator 94. The motor rotor 92 is positioned around a portion of the first shaft 30, and the motor stator 94 is positioned around the motor rotor 92. At least one end of the motor rotor 92 and motor stator 94 along the direction of the first axis is offset from each other, such as one end of the motor rotor 92 and motor stator 94 being offset from each other when away from the first rotor 20 and the second rotor 40, while the other end is flush with each other. In another example, one end of the motor rotor 92 and motor stator 94 being flush with each other when away from the first rotor 20 and the second rotor 40, while the other end is offset from each other. In another example, one end of the motor rotor 92 and motor stator 94, which are separated from the first rotor 20 and the second rotor 40, are offset from each other, and the other end is also offset from each other.

[0107] In an optional embodiment of this disclosure, one end of the motor rotor 92 and motor stator 94 that is far from the first rotor 20 and the second rotor 40 is offset from each other, and the other end is also offset from each other. The one end of the motor rotor 92 and motor stator 94 that is far from the first rotor 20 and the second rotor 40 is offset from each other, and as a result, the ends of the motor rotor 92 and motor stator 94 that are far from the first rotor 20 and the second rotor 40 form a first distance L7, and the one end of the motor rotor 92 and motor stator 94 that is close to the first rotor 20 and the second rotor 40 is offset from each other, and as a result, the ends of the motor rotor 92 and motor stator 94 that are close to the first rotor 20 and the second rotor 40 form a second distance L8. The motor rotor 92 is closer to the first rotor 20 and the second rotor 40 than the motor stator 94. Therefore, in the embodiments of this disclosure, a closed magnetic loop is formed between the motor rotor 92 and the motor stator 94, and the motor rotor 92, as an electric conductor, is pulled by an electromagnetic force. The motor rotor 92 and the motor stator 94 are offset from each other, and the motor rotor 92 is closer to the first rotor 20 and the second rotor 40 than to the motor stator 94. As a result, the electromagnetic force generated by the drive motor 90 is no longer tangential to the outer circle of the motor rotor 92, but also generates an electromagnetic force on the opposite side from the side to which the motor rotor 92 is deflected along the first axial direction. That is, the electromagnetic force generated by the drive motor 90 is no longer tangential to the outer circle of the motor rotor 92, but also generates an electromagnetic force along the direction of the first axis toward the second direction H2. In this case, the combined electromagnetic force acting on the motor rotor 92 can be decomposed to obtain the electromagnetic force in the first axial direction.

[0108] In the case of a permanent magnet variable frequency motor, this electromagnetic force is always present between the motor rotor 92 and the motor stator 94. In the case of a three-phase asynchronous motor, this electromagnetic force is generated between the motor rotor 92 and the motor stator 94 immediately after the power to the drive motor is turned on. In the case of the first rotor 20 and / or the second rotor 40, an electromagnetic force exists along the direction of the first axis, and the first rotor 20 and the second rotor 40 are always reliably subjected to an axial force in a constant direction. Therefore, only one thrust bearing, such as the first thrust bearing 50, is needed, and there are no reverse thrust bearings in the entire mechanism.

[0109] Since the compressor 200 can employ a first rotor 20 and a second rotor 20 arranged laterally, the required electromagnetic force only needs to be slightly greater than the maximum static friction force of the axial system.

[0110] In optional embodiments of this disclosure, the lengths of the first distance L7 and the second distance L8 are the same. In the prior art, it may be understood that the motor rotor and motor stator of a drive motor are generally the same length and substantially flush at the two ends. In embodiments of this disclosure, the lengths of the first distance L7 and the second distance L8 are the same, and based on drive motors of related art, the motor rotor 92 and motor stator 94 can be directly offset to obtain the drive motor 90 as defined in embodiments of this disclosure. In this way, manufacturing and assembly are facilitated. It may also be understood that the lengths of the first distance L7 and the second distance L8 are different.

[0111] In embodiments of this disclosure, it should be noted that additional magnetic members may be placed within the compressor 200 to generate magnetic forces to realize the axial force directions of the first rotor 20 and the second rotor 40. It can be understood that the additional magnetic members within the compressor 200 may generate magnetic forces directly, or that power may be supplied to generate electromagnetic forces. It should also be understood that the magnetic members must be at a sufficiently long distance from the drive motor 90, or that a shielding structure may be placed outside the drive motor 90 so that the magnetic or electromagnetic forces generated by the magnetic members do not interfere with the drive motor 90.

[0112] In the compressor 200 shown in Figure 11, the second shaft 30 does not necessarily have a thrust bearing, the second rotor 40 may be made of a non-metallic material such as Peek material, or a collision prevention structure may be arranged on the inner wall of the second rotor 40 and the housing 60.

[0113] Referring to Figure 12, a schematic diagram of a part of a compressor according to the eleventh embodiment of this disclosure is shown. In the compressor 200 shown in Figure 12, the drive motor 90, the first rotor 20, and the second rotor 40 are arranged vertically. This can be understood as a gravity-type axial bearing structure. The first part 22 and the second part 24 of the first rotor 20 are arranged vertically, the third part 42 and the fourth part 44 of the second rotor 40 are arranged vertically, and the drive motor 90, the first rotor 20, and the second rotor 40 are arranged vertically. By rationally utilizing the weight of the first rotor 20, the second rotor 40, and the drive motor 90, it can be seen that in actual use, before power is turned on, after power is turned off, and when operation is unstable, the initial direction of minute misalignment is always downward, i.e., along the second direction H2. The downward initial stress needs to be balanced by fixed-point orientation through a technical solution. Assuming the initial stress direction is clearly downward, a first thrust bearing 50 (or angular contact bearing 50) needs to be added to the non-motor side, i.e., the upper end axial system of the first rotor 20 in a gravity-type structure as shown in Figure 12, i.e., the first shaft 10. In this way, when the initial stress occurs, the first thrust bearing 50 can pull the first rotor 20. Because the initial gravity is very small compared to the air pressure generated by the opposing first rotor 20 and second rotor 40 during operation, only one angular contact bearing 50 with high bearing capacity is required. The angular contact bearing 50 is positioned at the upper end and pulls the first shaft 10 and the first rotor 20 on the first shaft 10, as well as the second rotor 40 which engages with the first rotor 20, resulting in a short-term slight displacement. After normal operation, the axial air pressures of the first rotor 20 and the second rotor 40 can balance each other.

[0114] Theoretical studies suggest that opposing rotor structures of identical shape can generate identical air pressure. The axial air pressures are balanced, and angular contact bearings are not installed in the axial system. However, the initial stresses described above occur during actual use, causing the first rotor 20 and the second rotor 40 to shift. Furthermore, because there is no corresponding counterbalancing structure, the initial stresses gradually increase, and the final displacement and deformation of the first rotor 20 and the second rotor 40 become larger than the end face clearance between the first rotor 20 and the second rotor 40, creating risks such as scratching of the end faces of the first rotor 20 and the second rotor 40 by the housing 60, jamming of the first rotor 20 and the second rotor 40, and wear. Conventionally, in the structure of a four-rotor compressor with non-oriented fixed point settings to counteract the initial stresses, one or more angular contact bearings are installed on both sides, resulting in significant cost waste, redundant product structure, increased operating power consumption, and decreased product energy efficiency.

[0115] According to embodiments of the present disclosure, since the first rotor 20 and the second rotor 40 of the gravity-type structure generate downward initial stress, it is clear that the initial misalignment direction of the first shaft 10 and the first rotor 20 on the first shaft 10 is downward. The angular contact bearing 50 is configured on the non-motor side of the first rotor 20, i.e., on the axial system above the first rotor 20, and precisely supports the short-term slight misalignment that occurs when the first rotor 20 and the second rotor 40 are unstable, thereby effectively preventing the housing 60 from scratching the end faces of the first rotor 20 and the second rotor 40. Structurally, the number of bearings is reduced, assembly difficulty is reduced, transient redundancy of the axial system is prevented, the configuration of moving parts is reduced, material and production costs are reduced, and energy efficiency is improved.

[0116] In addition, in the compressor 200 shown in Figure 12, the second shaft 30 does not necessarily have to be provided with a thrust bearing, the second rotor 40 may be made of a non-metallic material such as Peek material, or a collision prevention structure may be arranged on the inner wall of the second rotor 40 and the housing 60.

[0117] Embodiments of the present disclosure achieve unidirectional axial force, i.e., orientation of axial force, requiring only one thrust bearing on one shaft, or one thrust bearing on one of two shafts and no thrust bearing on the other. Compared to conventional compressors that require two thrust bearings on one shaft, embodiments of the present disclosure can reduce this to one thrust bearing on one shaft. Furthermore, the axial force orientation technology ensures that the machine always maintains the axial force in a preset direction during operation, thus guaranteeing stable operation of the machine. Guaranteed stable operation of the machine allows for a reduction in the overall size of the screw compressor and thus reduces costs.

[0118] Furthermore, compared to the prior art, the embodiments of the present disclosure can reduce the use of thrust bearings, thereby reducing machine losses and lubrication oil demand, further reducing the failure rate of the compressor 200, and extending the service life of the compressor.

[0119] In the compressor 200 in one or more of the above embodiments, the first portion 222 and the second portion 242 of the first rotor 20 and / or the third portion 422 and the fourth portion 442 of the second rotor 24 can be understood as a rotor assembly or rotor set. In other words, in one or more of the above embodiments, the first rotor 20 and the second rotor 40 of the compressor 200 can be understood as a rotor assembly or rotor set.

[0120] In one or more of the above embodiments, the compressor 200 can be applied to an air conditioner.

[0121] One embodiment of the present disclosure further provides an air conditioner including a compressor 200 defined according to one or more combinations of the above embodiments.

[0122] The rotor assemblies, compressors, and air conditioners according to embodiments of the present disclosure are described in detail above, and specific examples are used herein to illustrate the principles and implementations of the present disclosure. The above description of embodiments is used solely to aid in understanding the methods and central concepts of the present disclosure. Furthermore, those skilled in the art will see variations in specific embodiments and scope based on the concepts of the present disclosure. In summary, the contents of this description should not be understood as limiting the present disclosure. [Explanation of Symbols]

[0123] 10. First shaft 11. The first axis 12 First end 14. Second end 20 First Rotor 22 Part 1 221 First air supply port 222 First spiral feather 223 First exhaust end face 24 Part 2 241 Second air supply port 242 Second spiral feather 243 Second exhaust end face 30 Second shaft 31. The second axis 32 Third end 34 The fourth end 40 Second rotor 42 Third part 421 Third air supply port 422 Third spiral feather 423 Third exhaust end face 44 Part 4 442 The fourth spiral feather 443 Fourth exhaust end face 50 First thrust bearing 60 Housing 62 Fourth air supply port 64 Fifth air supply port 70 Second thrust bearing 80 Transmission Assembly 82 First transmission member 84 Second transmission component 90 Drive motor 92 Motor rotor, motor stator 200 Compressor 201 First exhaust port 202 Second exhaust port 203 Intake port H1 First direction H2 Second direction L1 Distance between the first air supply port and the first exhaust end face L2 Distance between the second air supply port and the second exhaust end face L3 Length of the first exhaust port along the first direction L4 Length of the second exhaust port along the second direction L5 Length of the first part along the direction of the first axis L6 Length of the second portion along the direction of the first axis L7 First distance L8 Second distance

Claims

1. A compressor (200), A first rotor (20) rotatable about a first shaft (11), wherein the first rotor (20) comprises a first portion (22) and a second portion (24), A first shaft (10) configured to support the first portion (22) and the second portion (24), wherein the first shaft (10) has a first end (12) and a second end (14) located on opposite sides, A housing (60) that accommodates a part of the first shaft (10) and the first rotor (20), Equipped with, The first rotor (20) is configured such that a preset force is applied to it during rotation in a direction from the first end (12) toward the second end (14), or from the second end (14) toward the first end (12). The compressor (200) is A second rotor (40) rotatable about a second shaft (31), wherein the second rotor (40) comprises a third portion (42) that engages with the first portion (22) and a fourth portion (44) that engages with the second portion (24), A second shaft (30) configured to support the third portion (42) and the fourth portion (44), The housing (60) accommodates a part of the second shaft (30) and the second rotor (40), Furthermore, The second rotor (40) is configured such that a preset force is applied to it in a direction from the first end (12) towards the second end (14) or from the second end (14) towards the first end (12) while the first rotor (20) and the second rotor (40) are rotating. A compressor (200) wherein a first air supply hole (221) is provided in the first portion (22) and / or the third portion (42), and a second air supply hole (241) is provided in the second portion (24) and / or the fourth portion (44), and the first air supply hole (221) and the second air supply hole (241) are configured to be different from each other so as to create a pressure difference during the rotation of the first rotor (20) and the second rotor (40) in order to form the preset force.

2. The shape of the first part (22) differs from the shapes of the second part (24) and the fourth part (44), and / or The compressor (200) according to claim 1, wherein the shape of the third portion (42) differs from the shapes of the second portion (24) and the fourth portion (44), and as a result, a pressure difference is generated during the rotation of the first rotor (20) and the second rotor (40), thereby forming the preset force.

3. The compressor (200) according to claim 1 or 2, wherein the shape of the first portion (22), the second portion (24), the third portion (42), and the fourth portion (44) includes one of the following: length, number of helical blades, end face profile, density of helical blades, and diameter.

4. The number of the first air supply holes (221) is different from the number of the second air supply holes (241), and / or The size of the first air supply hole (221) is different from the size of the second air supply hole (241), and / or The distance between the first air supply hole (221) and the end face of the first portion (22) that is away from the second portion (24) is different from the distance between the second air supply hole (241) and the end face of the second portion (24) that is away from the first portion (22), and / or The compressor (200) according to claim 1, wherein the distance between the first air supply hole (221) and the end face of the third portion (42) that is separated from the fourth portion (44) is different from the distance between the second air supply hole (241) and the end face of the fourth portion (44) that is separated from the third portion (42).

5. A compressor (200) according to any one of claims 1 to 4, wherein an air supply hole is provided in at least one of the first portion (22) and the third portion (42), and / or an air supply hole is provided in at least one of the second portion (24) and the fourth portion (44).

6. A portion of the housing (60) corresponding to the first portion (22) has a different shape from the portion of the housing (60) corresponding to the second portion (24) and the fourth portion (44), and / or A compressor (200) according to any one of claims 1 to 5, wherein a portion of the housing (60) corresponding to the third portion has a different shape from the portion of the housing (60) corresponding to the second portion (24) and the fourth portion (44), thereby generating a pressure difference during the rotation of the first rotor (20) and the second rotor (40) to form the preset force.

7. A compressor (200) according to any one of claims 1 to 6, wherein the housing (60) is provided with a first exhaust port (201) and a second exhaust port (202), and the length of the first exhaust port (201) in the direction from the first end (12) toward the second end (14) is different from the length of the second exhaust port (202) in the direction from the second end (14) toward the first end (12).

8. A first air supply hole (221) is provided in the portion of the housing (60) corresponding to the first portion (22) and / or the portion of the housing (60) corresponding to the third portion (42), and a second air supply hole (241) is provided in the portion of the housing (60) corresponding to the second portion (24) and / or the portion of the housing (60) corresponding to the fourth portion (44). The number of the first air supply holes (221) is different from the number of the second air supply holes (241), and / or The size of the first air supply hole (221) is different from the size of the second air supply hole (241), and / or The distance between the first air supply hole (221) and the end face of the first portion (22) that is away from the second portion (24) is different from the distance between the second air supply hole (241) and the end face of the second portion (24) that is away from the first portion (22), and / or The compressor (200) according to any one of claims 1 to 6, wherein the distance between the first air supply hole (221) and the end face of the third portion (42) that is separated from the fourth portion (44) is different from the distance between the second air supply hole (241) and the end face of the fourth portion (44) that is separated from the third portion (42).

9. A compressor (200) according to any one of claims 1 to 6, wherein an air supply hole is provided in at least one of the portion of the housing (60) corresponding to the first portion (22) and the portion of the housing (60) corresponding to the third portion (42), and / or an air supply hole is provided in at least one of the portion of the housing (60) corresponding to the second portion (24) and the portion of the housing (60) corresponding to the fourth portion (44).

10. The first portion (22) and the second portion (24) are positioned along the direction of gravity, the third portion (42) and the fourth portion (44) are positioned along the direction of gravity, and the gravity of the first portion (22), the second portion (24), the third portion (42), the fourth portion (44), the first shaft (10) and the second shaft (30) applies the preset force to the first rotor (20) and the second rotor (40) during their rotation, or A compressor (200) according to any one of claims 1 to 6, wherein the arrangement directions of the first portion (22) and the second portion (24) are at an angle of less than 90 degrees with respect to the direction of gravity, the arrangement directions of the third portion (42) and the fourth portion (44) are the same as the arrangement directions of the first portion (22) and the second portion (24), and the preset force is applied to the first rotor (20) and the second rotor (40) during their rotation due to the force components of the first portion (22), the second portion (24), the third portion (42), the fourth portion (44), the first shaft (10), and the second shaft (30) along the direction of gravity.

11. The compressor (200) according to any one of claims 1 to 10, further comprising a magnetic member, wherein the magnetic member is configured to generate a magnetic force such that the preset force is applied to the first rotor (20) and the second rotor (40) during rotation.

12. The system further comprises an oil passage system such that the pressure of the oil passage system acting on the first end (12) is lower than the pressure of the oil passage system acting on the second end (14), and as a result, the preset force is applied to the first rotor (20) and the second rotor (40) during rotation, or The compressor (200) according to any one of claims 1 to 11, wherein the pressure of the oil passage system acting on the third end (32) is lower than the pressure of the oil passage system acting on the fourth end (34), and as a result, the preset force is applied to the first rotor (20) and the second rotor (40) during rotation.

13. A first thrust bearing (50) is located at the first end (12) or the second end (14), The preset force is applied to the first thrust bearing (50). A compressor (200) according to any one of claims 1 to 12, further comprising the above.

14. A compressor (200) according to any one of claims 1 to 13, wherein the first shaft (10) is not provided with a thrust bearing, and both the first portion (22) and the second portion (24) are made of a non-metallic material.

15. A compressor (200) according to any one of claims 1 to 14, wherein the first shaft (10) is not provided with a thrust bearing, a first collision prevention structure is disposed between the end of the first portion (22) that is separated from the second portion (24) and the housing (60) of the compressor (200), and a second collision prevention structure is disposed between the end of the second portion (24) that is separated from the first portion (22) and the housing (60) of the compressor (200).

16. A first thrust bearing (50) is positioned at the first end (12) or the second end (14), A second thrust bearing (70) is positioned at the third end (32) or the fourth end (34), wherein the preset force is applied to the first thrust bearing (50) and the second thrust bearing (70), A compressor (200) according to any one of claims 1 to 15, further comprising the above.

17. The present invention further comprises a first thrust bearing (50) disposed at the first end (12) or the second end (14), wherein the preset force is applied to the first thrust bearing (50), The second shaft (30) is not provided with a thrust bearing, and the third portion (42) and the fourth portion (44) are made of non-metallic material. The compressor (200) according to any one of claims 1 to 16, wherein the first portion (22) and / or the second portion (24) are integrally formed with the first shaft (10), and the third portion (42) and the fourth portion (44) are rotatable about the second shaft (30).

18. The present invention further comprises a first thrust bearing (50) disposed at the first end (12) or the second end (14), wherein the preset force is applied to the first thrust bearing (50), The first shaft (10) is not provided with a thrust bearing, the third collision prevention structure is positioned between the end of the third portion (42) that is separated from the fourth portion (44) and the housing (60) of the compressor (200), and the fourth collision prevention structure is positioned between the end of the fourth portion (44) that is separated from the third portion (42) and the housing (60) of the compressor (200), The compressor (200) according to any one of claims 1 to 17, wherein the first portion (22) and / or the second portion (24) are integrally formed with the first shaft (10), and the third portion (42) and the fourth portion (44) are rotatable about the second shaft (30).

19. Housing (60) and A first rotor (20) rotatable within the housing (60) about a first shaft (11), wherein the first rotor (20) comprises a first portion (22) and a second portion (24), A second rotor (40) rotatable within the housing (60) about a second shaft (31), wherein the second rotor (40) comprises a third portion (42) that engages with the first portion (22) and a fourth portion (44) that engages with the second portion (24), A first air supply hole (221) is provided in at least one of the first portion (22), the third portion (42), a portion of the housing (60) corresponding to the first portion (22), and a portion of the housing (60) corresponding to the third portion (42), and a second air supply hole (241) is provided in at least one of the second portion (24), the fourth portion (44), a portion of the housing (60) corresponding to the second portion (24), and a portion of the housing (60) corresponding to the fourth portion (44), The number of the first air supply holes (221) is less than the number of the second air supply holes (241), and / or The size of the first air supply hole (221) is smaller than the size of the second air supply hole (241), and / or A compressor (200) in which the distance between the first air supply hole (221) and the end face of the first portion (22) that is away from the second portion (24) is longer than the distance between the second air supply hole (241) and the end face of the second portion (24) that is away from the first portion (22).

20. A first shaft (10) supporting the first portion (22) and the second portion (24), A second shaft (30) supporting the third portion (42) and the fourth portion (44), A first thrust bearing (50) is positioned on the first shaft (10) and on the same side of the first portion (22) or the second portion (24), The compressor (200) according to claim 19, further comprising the above.

21. A first rotor (20) comprising a first part (22) and a second part (24) that are rotatable about a first shaft (11), A second rotor (40) rotatable about a second shaft (31), wherein the second rotor (40) comprises a third portion (42) that engages with the first portion (22) and a fourth portion (44) that engages with the second portion (24), Equipped with, A first air supply hole (221) is provided in the first portion (22) and / or the third portion (42), and a second air supply hole (241) is provided in the second portion (24) and / or the fourth portion (44), The number of the first air supply holes (221) is less than the number of the second air supply holes (241), and / or The size of the first air supply hole (221) is smaller than the size of the second air supply hole (241), and / or A rotor assembly in which the distance between the first air supply hole (221) and the end face of the first portion (22) that is away from the second portion (24) is longer than the distance between the second air supply hole (241) and the end face of the second portion (24) that is away from the first portion (22).

22. An air conditioner comprising a compressor (200) according to any one of claims 1 to 20, or a rotor assembly according to claim 21.

Citation Information

Patent Citations

  • Screw compressor

    JP1985249689A

  • Screw fluid machine

    JP1989063689A

  • Screw compressor

    JP2008127990A