Rotating machinery

Abstract

A rotary machine includes: an electric motor; an impeller that rotates by the drive of the electric motor, sucks in gas, and compresses it; a housing that houses the impeller and has a gas suction port; a radiator provided in the housing; heat dissipation fins provided in the radiator and configured to be able to perform heat exchange with the gas passing through the suction port; and an inverter that controls the drive of the electric motor and is connected to the radiator.

Description

Technical Field

[0001] The present disclosure relates to rotary machinery. Background Art

[0002] In Patent Document 1, a centrifugal compressor is disclosed, in which a turbine impeller is rotated by exhaust gas from an engine, and a compressor impeller coaxially provided with the turbine is rotated via a rotating shaft, thereby supplying compressed air to the engine. In Patent Documents 2 and 3, rotary machinery in which a compressor impeller is rotated by driving of an electric motor is disclosed. In Patent Document 4, a compressor in which a compression mechanism compresses a refrigerant by driving of an electric motor is disclosed. In Patent Document 5, a centrifugal compressor in which a compressor impeller is rotated by driving of an electric motor is disclosed. In Patent Document 6, an electric motor that rotates a shaft is disclosed. In Patent Document 7, an electric blower is disclosed. In Patent Document 8, an inverter-integrated alternating-current electric motor is disclosed. In these prior arts, for example, in Patent Documents 2 and 3, an inverter that drives and controls an electric motor for rotating a compressor impeller is disclosed. The inverter generates heat when driving and controlling the electric motor, and thus needs to be appropriately cooled.

[0003] Patent Document 1: International Publication No. 2012 / 102146

[0004] Patent Document 2: Japanese Patent Application Laid-Open No. 2012-62777

[0005] Patent Document 3: Japanese Patent Application Laid-Open No. 2013-176193

[0006] Patent Document 4: Japanese Patent Application Laid-Open No. 2008-57426

[0007] Patent Document 5: Japanese Patent Application Laid-Open No. 2013-24057

[0008] Patent Document 6: Japanese Patent Application Laid-Open No. 2013-188105

[0009] Patent Document 7: Japanese Patent Application Laid-Open No. 1991-111700

[0010] Patent Document 8: Japanese Patent Application Laid-Open No. 2004-274992

[0011] The inverter is provided, for example, in a housing that houses the electric motor. In the housing, a passage and a pipe for allowing a refrigerant for cooling the electric motor and the inverter to pass through are provided. In order to appropriately cool the inverter using the refrigerant, the structure of the passage and the pipe for allowing the refrigerant to pass through easily becomes complicated, and there are also structural limitations for forming the passage and the pipe, making it difficult to effectively utilize the space. Summary of the Invention

[0012] The present disclosure describes a rotating machine that can both cool an inverter and effectively utilize space.

[0013] One aspect of the present disclosure is a rotating machine including: an electric motor; an impeller that rotates by the drive of the electric motor, sucks in gas, and compresses it; a housing that houses the impeller and has a gas suction port; a radiator provided in the housing; heat sinks provided on the radiator and configured to perform heat exchange with the gas passing through the suction port; and an inverter that controls the drive of the electric motor and is connected to the radiator.

[0014] In addition, one aspect of the present disclosure is a rotating machine including: an electric motor; an impeller that rotates by the drive of the electric motor, sucks in gas, and compresses it; an impeller housing that houses the impeller; a pipe portion connected to the impeller housing to form a gas suction port; an inverter that abuts against the pipe portion and controls the drive of the electric motor; and heat sinks that protrude from the inner peripheral surface of the pipe portion and are arranged on the gas flow path.

[0015] According to certain aspects of the present disclosure, it is possible to both cool the inverter and effectively utilize space. BRIEF DESCRIPTION OF THE DRAWINGS [[ID=!3]]

[0016] Figure 1 is a schematic explanatory diagram showing a rotating machine according to an embodiment of the present disclosure.

[0017] Figure 2 is an enlarged cross-sectional view showing a compressor.

[0018] Figure 3 is along Figure 2 cross-sectional view taken along line III-III.

[0019] Figure 4 is a schematic cross-sectional view showing the flow of air passing through the suction port. FIG. (a) is a mode with heat sinks, and FIG. (b) is a comparative mode without heat sinks.

[0020] Figure 5 is a curve chart showing the relationship between flow rate and pressure ratio.

[0021] Figure 6 is an enlarged perspective view showing a compressor section according to another embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] An example of the present disclosure is a rotating machine, comprising: an electric motor; an impeller that rotates by the drive of the electric motor, sucks in gas, and compresses it; a housing that houses the impeller and has a gas suction port; a radiator provided in the housing; heat dissipation fins provided on the radiator and configured to be able to perform heat exchange with the gas passing through the suction port; and an inverter that controls the drive of the electric motor and is connected to the radiator.

[0023] An example of the present disclosure includes an inverter that is thermally connected to the heat dissipation fins via the radiator. The heat dissipation fins are configured to be able to perform heat exchange with the gas passing through the suction port. That is, it is possible to cool the inverter by using the gas sucked in from the suction port due to the rotation of the impeller. As a result, even if the cooling flow path for the inverter is reduced, the inverter can be cooled. In addition, it is also possible to omit the cooling flow path for the inverter according to the flow rate of the gas passing through the suction port. That is, it is also possible to reduce the space for forming the cooling flow path for the inverter and effectively utilize the space.

[0024] In some examples, it may be configured that: the inverter is annular and is arranged to surround the suction port. Since the annular inverter surrounds the suction port, it is difficult for the cooling effect to deviate in the circumferential direction of the inverter, and the inverter can be cooled uniformly in the circumferential direction of the inverter.

[0025] In some examples, it may be configured that: the heat dissipation fins protrude from the inner circumferential surface of the suction port and are arranged on the gas flow path. Since the heat dissipation fins protrude from the inner circumferential surface of the suction port, they directly contact the gas passing through the suction port to take away heat. As a result, the cooling efficiency of the inverter can be improved.

[0026] In some examples, it may be configured that: the heat dissipation fins extend in the direction along the rotation axis of the impeller. The flow of the gas passing through the suction port is likely to be disordered near the inner circumferential surface of the suction port. On the other hand, in this rotating machine, the heat dissipation fins make the flow neat in the direction along the rotation axis of the impeller, so it is easy to obtain rectification and the surge margin can be improved.

[0027] In some examples, it may be configured that: the length of the heat dissipation fins in the direction along the rotation axis is longer than the height protruding from the inner circumferential surface. As a result, it is possible to simultaneously reduce the pressure loss of the gas passing through the suction port and improve the cooling efficiency of the inverter.

[0028] In some examples, it may be configured that: the radiator includes a pipe portion forming the suction port and a flange portion protruding outward from the pipe portion. In addition, it may be configured that: the inverter is annular and abuts against the flange portion, thereby being connected to the radiator. Since the inverter is arranged to surround the suction port via the flange portion, there is no deviation in the circumferential direction and it can be cooled uniformly.

[0029] In some examples, it can be configured such that the radiator has a pipe portion forming a suction port, the frequency converter abuts against the outer peripheral surface of the pipe portion, thereby connecting to the radiator, and the fins protrude from the inner peripheral surface of the pipe portion.

[0030] In some examples, it can be configured such that the fins are arranged at equal intervals in the circumferential direction around the rotation axis of the impeller.

[0031] In some examples, it can be configured such that the radiator has an inner pipe portion forming a suction port and an outer pipe portion provided outside the inner pipe portion, the fins are arranged between the inner pipe portion and the outer pipe portion, and are connected in a manner capable of exchanging heat with the inner pipe portion.

[0032] An example of the present disclosure is a rotary machine, comprising: an electric motor; an impeller that rotates by the drive of the electric motor, sucks in a gas and compresses it; an impeller housing that houses the impeller; a pipe portion that is connected to the impeller housing and forms a suction port for the gas; a frequency converter that abuts against the pipe portion and controls the drive of the electric motor; and fins that protrude from the inner peripheral surface of the pipe portion and are arranged on the gas flow path.

[0033] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In addition, in the description of the drawings, the same reference numerals are assigned to the same elements, and repeated descriptions are omitted.

[0034] Figure 1 An example of the rotary machine 1 in the present disclosure is shown. Specifically, it is an electric-assisted turbocharger. The rotary machine 1 of the present disclosure comprises: a turbine 2 that rotates by receiving the flow of exhaust gas; a rotating shaft 3 that transmits the rotational force of the turbine 2; and a compressor 4 that utilizes the rotational force of the turbine 2 to draw in air A (an example of a gas) and compress it. In addition, an electric motor 5 is arranged between the turbine 2 and the compressor 4 in the rotary machine 1. The drive of the electric motor 5 is controlled by a frequency converter 6.

[0035] The electric motor 5 is housed in a motor housing 50. At one end of the motor housing 50, that is, on one side surface in the direction along the rotating shaft 3, a turbine housing 21 is fixed. A turbine impeller 22 that transmits the rotational force to the rotating shaft 3 is arranged in the turbine housing 21. At the other end of the motor housing 50, that is, on the other side surface in the direction along the rotating shaft 3, a compressor housing 41 is fixed. A compressor impeller 42 that rotates by the rotational force of the rotating shaft 3 is arranged in the compressor housing 41.

[0036] The electric motor 5 includes a rotor 51 fixed to the rotating shaft 3 and a stator 52 disposed so as to surround the rotor 51. The stator 52 includes a core portion fixed to the motor housing 50 and a coil 52a wound around the core portion. The coil 52a is connected to the frequency converter 6 so as to be energizable. The electric motor 5 controls the rotational speed by controlling the frequency of the electric power through the frequency converter 6.

[0037] A first bearing 53 and a second bearing 54 for supporting the rotating shaft 3 so that it can rotate are provided in the motor housing 50. The first bearing 53 is disposed between the electric motor 5 and the compressor housing 41. The second bearing 54 is disposed between the electric motor 5 and the turbine housing 21. In addition, a cooling flow path 55 for cooling the electric motor 5 is formed in the motor housing 50. The cooling flow path 55 is provided so as to surround the stator 52. The refrigerant cooled by the heat exchanger 7 is introduced into the cooling flow path 55. For example, in the case of a water-cooled type, a liquid such as water can be used as the refrigerant.

[0038] As Figure 2 shown, a compressor impeller 42 that rotates by the action of the turbine 2 and the drive of the electric motor 5 is housed in the compressor housing 41. The compressor impeller 42 sucks in air A by rotation and compresses it. The compressor housing 41 includes an impeller housing 8 that houses the compressor impeller 42 and a tubular radiator 9 that forms a suction port 10.

[0039] A diffuser portion 81 for boosting the pressure is provided in the impeller housing 8. The diffuser portion 81 is provided around the compressor impeller 42. And, a scroll 82 and a discharge port 83 that communicate with the diffuser portion 81 are formed in the impeller housing 8. The discharge port 83 communicates with the scroll 82. The compressed air Ax (compressed gas) that has passed through the scroll 82 is discharged from the discharge port 83. In addition, the impeller housing 8 has an end portion (inlet portion) connected to the radiator 9. The impeller housing 8 has a flange-shaped connecting portion 84 that projects outward at its end portion. The inner diameter of the internal flow path 85 of the impeller housing 8 expands in a conical shape toward the inlet portion.

[0040] The radiator 9 includes a pipe portion 91 that is connected to the impeller housing 8 to form a suction port 10 for air A and a flange portion 92 that projects outward from the pipe portion 91. The flange portion 92 of the radiator 9 abuts against the connecting portion 84 of the impeller housing 8, so that the radiator 9 is fixed. In addition, the connection method between the impeller housing 8 and the radiator 9 can also be other methods, and the impeller housing 8 and the radiator 9 can also be integrally formed or integrated by welding or the like.

[0041] The inner peripheral surface 91a of the pipe section 91 corresponds to the inner peripheral surface of the suction port 10. A plurality of heat radiating fins 11 protruding from the inner peripheral surface 91a toward the center (rotation axis Lx) are provided on the pipe section 91. That is, the heat radiating fins 11 are arranged on the flow path C through which the air A passes. As a result, the heat radiating fins 11 are arranged so as to be able to perform heat exchange with the air A passing through the suction port 10. The plurality of heat radiating fins 11 in the present disclosure are arranged at equal intervals in the circumferential direction Cd (refer to Figure 3 ) around the rotation axis Lx. The heat radiating fins 11 are rectangular plate-shaped and extend in the direction along the rotation axis Lx. The length L of the heat radiating fins 11 in the direction along the rotation axis Lx is longer than the height H protruding from the inner peripheral surface 91a of the pipe section 91.

[0042] As Figure 2 and Figure 3 shown, an inverter 6 is fixed (connected) to the flange portion 92 of the radiator 9. That is, the inverter 6 is thermally connected to the radiator 9. In addition, the so-called thermal connection means a connection capable of performing heat exchange, and includes not only a physically direct contact method, but also an indirect connection method of interposing a heat conduction material such as thermal grease. In addition, the so-called indirect connection method can also be defined as a state where the thermal resistance is smaller than the thermal resistance in a state where an air layer is interposed.

[0043] In addition, the inverter 6 is circular (ring-shaped) and is arranged so as to surround the suction port 10 when viewed in the direction along the rotation axis Lx. The surface of the substrate 61 of the inverter 6 abuts against the flange portion 92, thereby being thermally connected. The inner peripheral edge 6a of the inverter 6 abuts against the outer peripheral surface 91b of the pipe section 91, thereby being thermally connected.

[0044] Devices 62 such as IGBT, bipolar transistors, MOSFETs, or GTOs, and power storage devices 63 such as capacitors (Capacitor) are assembled on the substrate 61 of the inverter 6. The lead wires led out from the inverter 6 are connected to the coil 52a of the electric motor 5 (stator 52).

[0045] Next, the operation and effects of the rotating machine 1 of the present disclosure will be described. The inverter 6 is connected to the heat radiating fins 11 via the radiator 9. The heat radiating fins 11 are arranged so as to be able to perform heat exchange with the air A passing through the suction port 10. That is, the rotating machine 1 can use the air A sucked from the suction port 10 by the rotation of the compressor impeller 42 to cool the inverter 6. As a result, in the rotating machine 1 of the present disclosure, there is no need to provide a cooling flow path for the inverter 6, and the inverter 6 can be effectively cooled. For example, by using the air A, the inverter 6 can be cooled to below 40°C even in summer.

[0046] In addition, if the compressor impeller 42 operates at a high load, the temperature of the frequency converter 6 also tends to rise. However, due to the high-load operation of the compressor impeller 42, the flow rate of the air A increases. At this time, the flow rate of the air A that contacts the heat sink 11 and extracts heat also increases. From the perspective of the cooling effect, they can offset each other, so it is highly efficient.

[0047] In addition, in the rotating machine 1 of the present disclosure, it is assumed that the frequency converter 6 can be appropriately cooled by the air A passing through the suction port 10, so no other cooling flow path is formed. However, for example, an auxiliary cooling flow path branched from the cooling flow path 55 for the electric motor 5 may be formed, and the frequency converter 6 can be cooled auxiliarily through this cooling flow path. In this case, the cooling flow path for cooling the frequency converter 6 can also be an auxiliary flow path, and a simple structure can be achieved.

[0048] In addition, the rotating machine 1 of the present disclosure is a turbocharger, and a turbine 2 is provided on the side opposite to the compressor 4 with the motor housing 50 (electric motor 5) interposed therebetween. The turbine 2 becomes hot, which is disadvantageous from the perspective of cooling. However, in the rotating machine 1 of the present disclosure, since the frequency converter 6 is arranged at a position farther from the turbine 2 than the electric motor 5, it is easy to improve the cooling effect.

[0049] As described above, according to the rotating machine 1 of the present disclosure, it is possible to omit or suppress the use of the cooling flow path 55 for the frequency converter 6 auxiliarily. Therefore, the space for forming the cooling flow path for the frequency converter 6 can be reduced, and the space can be effectively utilized.

[0050] In addition, the frequency converter 6 is annular and arranged so as to surround the suction port 10. As a result, in the circumferential direction Cd of the frequency converter 6, that is, in the direction around the rotation axis Lx, the cooling effect is difficult to deviate, which is beneficial to the uniform cooling of the frequency converter 6.

[0051] In addition, the heat sink 11 protrudes from the inner peripheral surface 91a of the suction port 10 and is arranged on the flow path C of the air A. As a result, the heat sink 11 directly contacts the air A passing through the suction port 10 to extract heat, and the cooling efficiency of the frequency converter 6 can be improved.

[0052] In addition, the heat sink 11 extends in the direction of the rotation axis Lx of the compressor impeller 42, and the surge margin can be improved. Specifically, the performance at low motor speeds is improved. Refer to Figure 4 and Figure 5 to illustrate this effect. Figure 4 is a schematic cross-sectional view showing the flow of the air A passing through the suction port 10. Figure 4 (a) of is an embodiment of the present disclosure, and (b) of is a comparative embodiment without the heat sink 11. In addition, Figure 5It is a graph showing the relationship between flow rate and pressure ratio. The solid line represents the method of the present disclosure, and the dashed line represents the comparative method.

[0053] As Figure 4 shown in the (b) figure of [[ID=]], in the comparative method, there is a compressor impeller 101 that sucks in air A from the suction port 100 and compresses it. In the comparative method, the flow of air A through the suction port 100 is likely to be disturbed near the inner peripheral surface 100a of the suction port 100. On the other hand, as Figure 4 shown in the (a) figure of [[ID=]], in the rotary machine 1 of the present disclosure, the flow is made orderly in the direction of the rotation axis Lx of the compressor impeller 42 by the heat sink 11, and the surge margin at low flow rates (when the motor is running at low speed) can be improved.

[0054] In addition, as Figure 2 shown, the length L of the heat sink 11 in the direction along the rotation axis Lx is longer than the height H protruding from the inner peripheral surface 91a. As a result, it is possible to simultaneously reduce the pressure loss of air A passing through the suction port 10 and improve the cooling efficiency of the frequency converter 6.

[0055] In addition, the radiator 9 of the present disclosure includes a pipe portion 91 that forms the suction port 10 and a flange portion 92 that extends outward from the pipe portion 91. The frequency converter 6 is annular and abuts against the flange portion 92 and is fixed to the radiator 9. That is, since the frequency converter 6 is arranged so as to surround the suction port 10 via the flange portion 92, there is no deviation in the circumferential direction Cd, which is beneficial for uniform cooling.

[0056] Next, with reference to Figure 6 the rotary machine 1A according to other embodiments will be described. Figure 6 is a perspective view showing an enlarged view of a portion of the compressor 4A of the rotary machine 1A, particularly the portion where the suction port 10A is formed. In addition, the rotary machine 1A according to other embodiments has the same structure and configuration as the rotary machine 1 according to the above embodiment, and the same reference numerals are assigned to the same structure and configuration and the detailed description thereof is omitted.

[0057] As Figure 6 shown, in the compressor housing 41, there is a compressor impeller 42 that rotates by the drive of an electric motor 5A to suck in air A and compress it. The compressor housing 41 includes an impeller housing 8 that houses the compressor impeller 42 and a radiator 9A that forms the suction port 10A inside.

[0058] The radiator 9A includes a pipe portion 91A that is connected to the impeller housing 8 to form the suction port 10A of air A and a flange portion 92A that extends outward from the pipe portion 91A. In the flange portion 92A, the annular frequency converter 6 is fixed in a manner that enables heat exchange.

[0059] The pipe section 91A has a double-pipe structure, and a suction port 10A through which air A passes is formed in the inner cylindrical portion (inner pipe section 91c). In addition, heat radiating fins 11A protruding from the inner peripheral surface 91a are provided in the outer cylindrical portion (outer pipe section 91d). The heat radiating fins 11A are arranged between the outer pipe section 91d and the inner pipe section 91c. The heat radiating fins 11A are connected to the inner pipe section 91c in a manner capable of heat exchange and are arranged to be capable of heat exchange with the air A passing through the suction port 10A.

[0060] The heat radiating fins 11A function as the core part of the stator 52A, and a stator 52A is formed by winding a coil 52b around the heat radiating fins 11A. The heat radiating fins 11A around which the coil 52b is wound extend in the direction along the rotation axis Lx and are arranged to surround the rotor fixed to the rotating shaft 3, thereby forming an electric motor.

[0061] The frequency converter 6 according to the present disclosure is connected to the heat radiating fins 11A via the radiator 9A. The heat radiating fins 11A are arranged to be capable of heat exchange with the air A passing through the suction port 10A. That is, the frequency converter 6 can be cooled by using the air A sucked from the suction port 10A by the rotation of the compressor impeller 42. As a result, there is no need to provide a cooling flow path for the frequency converter 6, and the frequency converter 6 can be effectively cooled. In addition, the cooling flow path for the frequency converter 6 can be omitted according to the flow rate of the air A passing through the suction port 10A. That is, the space for forming the cooling flow path for the frequency converter 6 can also be reduced, and the space can be effectively utilized.

[0062] The present disclosure is not limited to the above-described embodiments. For example, in the above-described embodiments, as an example of a rotating machine, an electric assist type turbocharger is described, but it can be widely applied to rotating machines having an electric motor and an impeller for compressing a gas. For example, it can also be a rotating machine in which the impeller rotates on the main body by the drive of the electric motor without a turbine.

[0063] Description of reference numerals:

[0064] 1... Rotating machine; 5... Electric motor; 6... Frequency converter; 8... Impeller housing; 9... Radiator; 10... Suction port; 11... Heat radiating fins; 41... Compressor housing (housing); 42... Compressor impeller (impeller); 91... Pipe section; 91a... Inner peripheral surface (inner peripheral surface of the suction port); 92... Flange portion; A... Air (gas); H... Height of the heat radiating fins; L... Length of the heat radiating fins; Lx... Rotation axis; Cd... Circumferential direction.

Claims

1. A rotating machine, characterized in that, Comprising: An electric motor; An impeller that rotates by the drive of the electric motor, sucks in gas and compresses the gas; A housing that houses the impeller and has an intake port for the gas; A radiator disposed on the housing; Heat dissipation fins disposed on the radiator and configured to be able to exchange heat with the gas passing through the intake port; And An inverter that controls the drive of the electric motor and is connected to the radiator, The radiator has a pipe portion forming the intake port and a flange portion extending outward from the outside of the pipe portion, The inverter abuts against the flange portion, thereby being connected to the radiator.

2. The rotary machine according to claim 1, wherein The inverter is annular and is arranged to surround the intake port.

3. The rotary machine according to claim 1 or 2, wherein The heat dissipation fins protrude from the inner peripheral surface of the intake port and are arranged on the gas flow path.

4. The rotary machine according to claim 3, wherein The heat dissipation fins extend in a direction along the rotation axis of the impeller.

5. The rotary machine according to claim 4, wherein The length of the heat dissipation fins in the direction along the rotation axis is longer than the height protruding from the inner peripheral surface.

6. The rotary machine according to claim 1 or 2, wherein The inverter abuts against the outer peripheral surface of the pipe portion, thereby being connected to the radiator, The heat dissipation fins protrude from the inner peripheral surface of the pipe portion.

7. The rotary machine according to claim 6, wherein The heat dissipation fins are arranged at equal intervals in the circumferential direction around the rotation axis of the impeller.

8. The rotary machine according to claim 1, wherein The pipe portion has an inner pipe portion forming the intake port and an outer pipe portion disposed outside the inner pipe portion, The heat dissipation fins are arranged between the inner pipe portion and the outer pipe portion and are connected to the inner pipe portion to be able to exchange heat.

9. A rotating machine, characterized in that, Comprising: An electric motor; An impeller that rotates by the drive of the electric motor, sucks in gas and compresses the gas; An impeller housing that houses the impeller; A pipe portion that is connected to the impeller housing and forms the intake port for the gas; An inverter that abuts against the pipe portion and controls the drive of the electric motor; Heat dissipation fins that protrude from the inner peripheral surface of the pipe portion and are arranged on the gas flow path; and A flange portion that extends outward from the pipe portion, The inverter abuts against the flange portion.

Images