Centrifugal compressor and impeller structure thereof

Abstract

The utility model discloses a centrifugal compressor which comprises a power component and a transmission shaft driven by the power component, at least one end of the transmission shaft is provided with an integrated impeller structure which is integrally formed, and the integrated impeller structure comprises at least two centrifugal impeller parts which are arranged adjacently and can conduct compression respectively. According to the technical scheme, when the centrifugal compressor is assembled, the integrated impeller structure is installed in a unified mode and then sealed in a unified mode, installation is convenient, and meanwhile sealing is more convenient. Due to unified installation, fixing structures between the transmission shaft and the transmission shaft can be reduced, meanwhile, the transmission shaft and the transmission shaft depend on each other, and strength can be improved. And meanwhile, due to integral forming, the process is well reduced, the independence of each compression cavity channel is not influenced, and the size and the weight are reduced. In conclusion, the centrifugal compressor can effectively solve the problem that the centrifugal impeller of an existing centrifugal compressor is unreasonable in arrangement. The utility model further discloses an impeller structure applied to the centrifugal compressor.

Description

Technical Field

[0001] The utility model relates to the technical field of compressors, and more specifically, to a centrifugal compressor and also to an impeller structure applied to the centrifugal compressor. Background Art

[0002] Existing multi-stage compression is usually achieved by using multiple impellers, with additional fixed components and connecting components. The impellers are arranged in sequence, and flow space for intake and exhaust must be reserved. Because the intake and exhaust are too close to each other, the pressure difference is large, the leakage loss is large, and simple isolation will also have a significant impact on efficiency, so the effect of implementing an integrated design is poor.

[0003] In the process of realizing the utility model, the inventor discovered that there are at least the following problems in the prior art: How to effectively solve the problem of unreasonable setting of centrifugal impellers in current centrifugal compressors is an urgent problem that technicians in this field need to solve. Utility Model Content

[0004] In view of this, the first object of the utility model is to provide a centrifugal compressor, which can effectively solve the problem of unreasonable centrifugal impeller setting in current centrifugal compressors. The second object of the utility model is to provide an impeller structure of a centrifugal compressor.

[0005] In order to achieve the above object, the utility model provides the following technical solutions:

[0006] A centrifugal compressor comprises a power component and a transmission shaft driven by the power component, wherein at least one end of the transmission shaft has an integrally formed impeller structure, and the integral impeller structure comprises at least two adjacently arranged centrifugal impeller parts capable of performing compression respectively.

[0007] In the above technical solution, when the centrifugal compressor is assembled, the integrated impeller structure is installed uniformly and then sealed uniformly, which makes installation and sealing more convenient. Due to the unified installation, the fixed structure between the drive shaft can be reduced, and at the same time, the strength can be improved by relying on each other. At the same time, due to the one-piece molding, the process is greatly reduced, that is, it does not affect the independence of each compression chamber channel, and reduces the size and weight. In summary, the centrifugal compressor can effectively solve the problem of unreasonable centrifugal impeller setting in current centrifugal compressors.

[0008] In some technical solutions, the two centrifugal impeller parts in the integrated impeller structure are arranged opposite to each other or back to back.

[0009] In some technical solutions, the integrated impeller structure is hollow.

[0010] In some technical solutions, at least one of the multiple centrifugal impeller parts is a primary compression part that directly introduces gas from the evaporator outlet, and the heat source part in the power component is located at one end of the power component away from the primary compression part.

[0011] In some technical solutions, at least one of the multiple centrifugal impeller parts is a high-stage compression part that directly introduces gas from the outlet of the primary compression part, and the high-stage compression part is arranged close to the power component relative to the primary compression part.

[0012] In some technical solutions, the two centrifugal impeller parts are arranged back to back, and the radial outer edge parts are connected, and the connection part forms a cylindrical surface that matches the sealing part.

[0013] In some technical solutions, the integrated impeller structure forms a groove on the inner side of the cylindrical surface.

[0014] In some technical solutions, the axial air inlets of the high-stage compression parts of the centrifugal impeller parts on both sides of the groove are communicated with the groove cavity of the groove.

[0015] In some technical solutions, an air guide groove or an air guide channel is provided on the side wall of the transmission shaft to connect the axial air inlet of the high-stage compression part and the groove cavity.

[0016] In some technical solutions, the integrated impeller structure is provided at both ends of the transmission shaft.

[0017] In order to achieve the above second purpose, the utility model also provides an impeller structure of a centrifugal compressor, the impeller structure of the centrifugal compressor includes a plurality of centrifugal impeller parts, at least two of the centrifugal impeller parts that are adjacently arranged and can compress gas respectively are integrally connected; and the two centrifugal impeller parts integrally connected are arranged back to back, and the radial outer edge parts are connected, and the connection forms a cylindrical surface of the matching sealing part; the inner side of the cylindrical surface forms a groove. Since the above centrifugal compressor has the above technical effects, the main distinguishing structure of the centrifugal compressor, that is, the impeller structure, should also have corresponding technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic diagram of the structure of a centrifugal compressor provided by an embodiment of the utility model;

[0020] Figure 2 for Figure 1 A schematic diagram of the enlarged structure at A in the middle;

[0021] Figure 3 A schematic diagram of the structure of the back-to-back integrated impeller structure provided in an embodiment of the utility model;

[0022] Figure 4 A schematic structural diagram of a relatively integrated impeller structure provided in an embodiment of the utility model.

[0023] The following are marked in the accompanying drawings:

[0024] Transmission shaft 1, power component 2, integrated impeller structure 3, sealing part 4, air guide groove 5;

[0025] Centrifugal impeller part 31 , primary compression part 32 , high-stage compression part 33 , groove 34 , and cylindrical surface 35 . DETAILED DESCRIPTION

[0026] The embodiment of the utility model discloses a centrifugal compressor, which effectively solves the problem of unreasonable arrangement of centrifugal impellers in current centrifugal compressors.

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] See also Figure 1-Figure 4 , Figure 1 A schematic diagram of the structure of a centrifugal compressor provided by an embodiment of the utility model; Figure 2 for Figure 1 A schematic diagram of the enlarged structure at A in the middle; Figure 3 A schematic diagram of the structure of the back-to-back integrated impeller structure provided in an embodiment of the utility model; Figure 4 A schematic structural diagram of a relatively integrated impeller structure provided in an embodiment of the utility model.

[0029] In some embodiments, this embodiment provides a centrifugal compressor. Specifically, the centrifugal compressor mainly includes a power component 2 , a transmission shaft 1 and a centrifugal impeller part 31 .

[0030] The transmission shaft 1 is driven by a power component 2, wherein the power component 2 is generally a motor assembly, and the motor assembly mainly includes a stator and a rotor, wherein the transmission connection between the rotor and the transmission shaft 1 is generally a key connection to transmit torque and avoid transmitting axial force, and of course, the rotor and the transmission shaft 1 can also be fixedly connected. Of course, the power component 2 can also be other structures, such as a hydraulic pump, etc.

[0031] One end of the transmission shaft 1 generally has a plurality of centrifugal impeller parts 31 to achieve multi-stage compression. Therefore, sealing is required between the adjacent centrifugal impeller parts 31. The centrifugal impeller part 31 is located in the fan compartment so that when it rotates with the transmission shaft 1, it can push the fan compartment air body to pressurize the axial air inlet air body toward the peripheral air outlet to achieve compression. Because different levels of centrifugal impeller parts 31 need to be set in different fan compartments, sealing requirements are generally formed between adjacent fan compartments.

[0032] At least one end of the transmission shaft 1 has an integrally formed integrated impeller structure 3, wherein the integral impeller structure 3 includes at least two centrifugal impeller parts 31 that are adjacently arranged and can be compressed separately. That is, there are at least two such centrifugal impeller parts 31 in the integral impeller structure 3, and the two centrifugal impeller parts 31 are adjacently arranged and can be compressed separately, so it is necessary to seal between the two centrifugal impeller parts 31 to avoid affecting mutual compression. Because it is an integrally formed connection, during installation, it is sufficient to consider the sealing uniformly, which reduces the difficulty of sealing.

[0033] In some embodiments, during installation, the integrated impeller structure 3 is installed uniformly and then sealed uniformly, which makes installation and sealing more convenient. Due to the unified installation, the fixed structure with the transmission shaft 1 can be reduced, and at the same time, the strength can be improved by relying on each other. At the same time, due to the one-piece molding, the process is greatly reduced, that is, it does not affect the independence of each compression chamber channel, and reduces the size and weight. In summary, the centrifugal compressor can effectively solve the problem of unreasonable centrifugal impeller setting of the current centrifugal compressor.

[0034] In some embodiments, in the integrated impeller structure 3, each centrifugal impeller part 31 can be arranged in the same direction, such as the axial air inlets are all facing the same direction. In order to better reduce the number of fixed structures and / or the connection strength, it is preferred here that the two centrifugal impeller parts 31 in the integrated impeller structure 3 are arranged oppositely or oppositely to balance the axial tension. It should be noted that the opposite arrangement refers to that the two centrifugal impeller parts 31 are arranged away from each other's axial air inlets, so as to be arranged oppositely. The relative arrangement refers to that the two centrifugal impeller parts 31 are arranged close to each other's axial air inlets, so as to be arranged oppositely. Both the opposite arrangement and the relative arrangement can better balance the axial tension. By balancing the axial tension between the two adjacent centrifugal impeller parts 31, the axial tension can be avoided from being transmitted over a long distance in the axial direction of the transmission shaft 1, and at least the axial long-distance tension can be reduced. The axial tension is balanced inside the two centrifugal impeller parts 31 to reduce the axial force between the transmission shaft 1, thereby reducing the strength requirements of the fixed structure.

[0035] In some embodiments, in order to better reduce energy consumption, it is preferred that the above-mentioned integrated impeller structure 3 is hollowed out so as to make the integrated impeller structure 3 lighter and reduce the rotational energy. At the same time, through the hollowing, the integrity of the fit between the outer side of the integrated impeller structure 3 and the sealing part 4 can be better ensured, and the fit between the inner side of the integrated impeller structure 3 and the transmission shaft 1 can be ensured. When the hollow setting is used, a through hole can be opened on the hole wall of the internal hole to connect to the outside to facilitate molding and avoid thermal expansion caused by internal closure.

[0036] In some embodiments, at least one of the plurality of centrifugal impeller parts 31 is a primary compression part 32 that directly introduces gas from the evaporator outlet, and the heat source component in the power component 2 is located at one end of the power component 2 away from the primary compression part 32. This is to prevent the temperature at the primary compression part 32 from being affected by the temperature of the heat source component and increasing, thereby affecting the air intake efficiency and effectively avoiding the compression efficiency.

[0037] In some embodiments, at least one of the multiple centrifugal impeller sections 31 can be a high-level compression section 33 that directly introduces gas from the outlet of the primary compression section 32, and the high-level compression section 33 is arranged close to the power component 2 relative to the primary compression section. By arranging the high-level compression section 33 close to the power component 2, the high-level compression section 33 can be cooled by using the power bin where the power component 2 is located, and cooling at this time can further increase the intake volume of the high-level compression section 33, reduce power, and improve the compression ratio. It should be noted that a cooling circuit is generally provided on the compressor to mainly cool the power component 2. The high-level compression section 33 is arranged close to the power component 2 compared to being arranged far away from the power component 2, which will increase the cooling requirements of the cooling circuit. At this time, the cooling efficiency of the cooling circuit can be correspondingly improved. It is also preferred that the axial air inlet of the high-level compression section 33 is arranged toward the power bin, which can reduce the dynamic sealing strength between the two compared to the circumferential air outlet being arranged close to the power bin.

[0038] In some embodiments, only one integrated impeller structure 3 may be provided at one end of the transmission shaft 1, and the integrated impeller structure 3 includes only two centrifugal impeller parts 31 that are arranged back to back with each other, and one of the two centrifugal impeller parts 31 is a high-stage compression part 33, and the other is a primary compression part, wherein the high-stage compression part 33 is closer to the power component 2 than the primary compression part, and the axial air inlet is close to the power component 2.

[0039] In some embodiments, the two centrifugal impeller parts 31 can be arranged back to back, and the radial outer edge parts are connected, and the connection forms a cylindrical surface 35 that matches the sealing part 4. By connecting the radial outer edge parts of the centrifugal impeller, the formation of the inner concave side cylindrical surface 35 can be avoided, thereby facilitating the sleeve installation of the sealing part 4 in the later stage. At least at one end of the cylindrical surface 35, the outer edge of the centrifugal impeller part 31 is not higher than the above-mentioned cylindrical surface 35 to ensure the sleeve installation of the sealing part 4. The axial length of the cylindrical surface 35 should not be too small, otherwise it is difficult to form a good dynamic seal. As shown in the accompanying drawings, the outer edge of the high-level compression part 33 is flush with the cylindrical surface 35. After the transmission shaft and the sealing part 4 are installed in place, the integrated centrifugal impeller structure 3 can be inserted in the direction toward the power component 2 and sleeved on the transmission shaft. The cylindrical surface 35 is arranged relative to the inner hole of the sealing part 4.

[0040] Specifically, the outer edge of the centrifugal impeller part 31 is a circumferential air outlet, and in particular, the cylindrical surface 35 is formed on the side of the outer edge away from the axial air inlet.

[0041] In addition, in order to facilitate the wind guidance, the channel between the axial air inlet and the circumferential air outlet forms arc-shaped side walls on both sides of the axial direction to facilitate the deflection of the wind body. Therefore, in order to better form the above-mentioned integrated impeller structure 3, it is preferred that the integrated impeller structure 3 forms a groove 34 on the inner side of the above-mentioned cylindrical surface 35, which is not only convenient for molding, but also avoids the formation of a larger solid structure on the inner side of the cylindrical surface 35, which is not conducive to heat dissipation during the molding process. At the same time, the above-mentioned groove 34 has a weight reduction effect. The groove 34 is preferably an annular groove, and the groove walls on both sides of the groove 34 preferably have an inwardly convex arc-shaped end to adapt to the arc structure of the channel wall. The groove 34 can also be arranged in sections along the circumferential direction. It is further preferred that the notch portion of the groove 34 is narrowed to increase the contact surface with the transmission shaft to improve the contact strength.

[0042] After the integrated impeller structure 3 is sleeved and installed on the transmission shaft 1, the groove 34 can be closed by the transmission shaft 1 to form a closed cavity. However, because the integrated impeller structure 3 will form a high temperature state when working, of course, it may also be formed due to the heat generated by other structures, resulting in the groove cavity of the groove 34 being in a high temperature state, and the high temperature state will force the internal gas to expand, resulting in excessive internal pressure, causing the integrated impeller structure 3 to deform, affecting the later work efficiency.

[0043] Based on the above reasons, it is preferred that the groove cavity of the groove 34 is communicated with the outside. And it is preferred that the axial air inlet of the high-level compression part 33 in the centrifugal impeller part 31 on both sides of the groove cavity is communicated with the groove cavity. The axial air inlet pressure of the high-level compression part 33 is the same as the circumferential air outlet pressure of the primary compression part 32, but is smaller than the circumferential air outlet of the high-level compression part 33, and is larger than the axial air inlet of the primary compression part 32, so it is an intermediate value, which makes the groove walls on both sides of the groove 34 not subject to large pressure difference and balanced. For the primary compression part 32, a supporting effect is also formed. As for the high-level compression part 33, although there is no very good supporting effect on its outer edge, due to the connection between the outer edge wall of the high-level compression part 33 and the primary compression part 32, a certain supporting effect can be formed, which can meet the edge support effect of the high-level compression part 33. Therefore, through the above-mentioned setting, the corresponding wind pressure support can be formed inside and outside the integrated impeller structure 3, reducing the strength requirements. It should be noted that the axial air inlet of the high-stage compression part 33 in the centrifugal impeller part 31 on both sides of the slot cavity is connected to the slot cavity. Correspondingly, the inner wall of the primary compression part 32 in the centrifugal impeller part 31 on both sides of the slot cavity and the transmission shaft should be sealed to avoid leakage. Of course, a small amount of leakage that does not significantly affect the air pressure in the slot cavity is allowed.

[0044] Of course, the groove cavity of the groove 34 can also be connected to the circumferential air outlet of the advanced compression part 33, or the axial air inlet of the primary compression part 32, but the supporting effect is not good. Of course, the groove cavity of the groove 34 can also be connected to the circumferential air outlet of the primary compression part 32. However, this requires opening a channel at the outer edge, which is easy to affect the strength of the integrated impeller structure 3.

[0045] In some embodiments, in order to avoid affecting the strength of the integrated impeller structure 3, it is preferred that an air guide groove 5 or an air guide channel is provided on the side wall of the transmission shaft 1 to connect between the axial air inlet of the high-level compression part 33 and the groove cavity. In order to facilitate molding, a plurality of air guide grooves 5 symmetrical with respect to the rotation center may be provided, wherein the cross-section of the air guide groove 5 is preferably arc-shaped, and the transition between the air guide groove 5 and the outer peripheral surface of the transmission shaft is rounded to avoid stress concentration. The cross-sectional area of ​​the air guide groove 5 does not need to be too large, so as to ensure that the gas is communicated between the axial air inlet of the high-level compression part 33 and the groove cavity. Of course, an air guide groove 5 or an air guide channel may also be provided on the inner wall of the high-level compression part 33 to connect between the axial air inlet of the high-level compression part 33 and the groove cavity.

[0046] In some embodiments, in order to better balance the axial tension, it is preferred that both ends of the transmission shaft 1 are provided with the integrated impeller structure 3. The integrated impeller structures 3 at both ends may have the same structure or different structures, such as one end is arranged opposite to the other end.

[0047] Based on the centrifugal compressor provided in the above embodiment, the utility model also provides an impeller structure, as shown in the attached Figure 3 , the impeller structure includes a plurality of centrifugal impeller parts, at least two of the centrifugal impeller parts that are adjacently arranged and can compress the gas respectively are integrally connected; and the two centrifugal impeller parts that are integrally connected are arranged back to back, and the radial outer edge parts are connected, and the connection forms a cylindrical surface that matches the sealing part; a groove is formed on the inner side of the cylindrical surface. Since the impeller structure is the main improved structure of the centrifugal compressor in some of the above-mentioned embodiments, please refer to the above-mentioned embodiments for the beneficial effects of the impeller structure. Specifically, the impeller structures that are integrally connected can be installed uniformly and then sealed uniformly, which is convenient for installation and sealing. Due to the unified installation, the fixed structure between the transmission shaft can be reduced, and at the same time, they rely on each other to improve the strength. At the same time, due to the one-piece molding, the process is greatly reduced, that is, it does not affect the independence of each compression chamber channel, and reduces the size and weight.

[0048] Specifically, the groove is preferably connected to the axial air inlet of the high-level compression part in the centrifugal impeller part on both sides of the groove. Specifically, the inner wall of the high-level compression part in the two centrifugal impeller parts connected by integral molding can be provided with an air guide groove or an air guide channel to connect the axial air inlet of the high-level compression part and the groove cavity of the groove. Of course, as in the above embodiment, the air guide groove or the air guide channel can also be set on the transmission shaft.

[0049] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0050] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A centrifugal compressor, comprising a power component and a transmission shaft driven by the power component, characterized in that: At least one end of the transmission shaft has an integrally formed impeller structure, and the integral impeller structure includes at least two adjacently arranged centrifugal impeller parts that can compress gas respectively.

2. The centrifugal compressor according to claim 1, characterized in that: The two centrifugal impeller parts in the integrated impeller structure are arranged opposite to each other or facing each other.

3. The centrifugal compressor according to claim 1, characterized in that: The integrated impeller structure is hollow.

4. The centrifugal compressor according to claim 1, characterized in that: At least one of the plurality of centrifugal impeller parts is a primary compression part that directly introduces gas from an outlet of the evaporator, and a heat source part in the power component is located at an end of the power component away from the primary compression part.

5. The centrifugal compressor according to claim 4, characterized in that: At least one of the plurality of centrifugal impeller sections is a high-stage compression section that directly introduces gas from an outlet of the primary compression section, and the high-stage compression section is disposed close to the power component relative to the primary compression section.

6. The centrifugal compressor according to any one of claims 1 to 5, characterized in that: The two centrifugal impeller parts are arranged back to back, and the radial outer edge parts are connected, and the connection part forms a cylindrical surface that matches the sealing part.

7. The centrifugal compressor according to claim 6, characterized in that: The integrated impeller structure forms a groove on the inner side of the cylindrical surface.

8. The centrifugal compressor according to claim 7, characterized in that: The axial air inlets of the high-stage compression part of the centrifugal impeller part on both sides of the groove are communicated with the groove cavity of the groove.

9. The centrifugal compressor according to claim 8, characterized in that: An air guide groove or an air guide channel is arranged on the side wall of the transmission shaft to connect the axial air inlet of the high-stage compression part with the groove cavity.

10. The centrifugal compressor according to claim 9, characterized in that The integrated impeller structure is disposed at both ends of the transmission shaft.

11. An impeller structure of a centrifugal compressor, characterized in that: It comprises a plurality of centrifugal impeller parts, at least two of which are adjacently arranged and capable of compressing gas respectively and are integrally connected; and the two integrally connected centrifugal impeller parts are arranged back to back and their radial outer edge parts are connected, and a cylindrical surface matching the sealing part is formed at the connection; a groove is formed on the inner side of the cylindrical surface.

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