Centrifugal compressor

Abstract

The present invention relates to a centrifugal compressor. Reliability is ensured. A first resin portion (60) and each second resin portion (70) are joined by insert molding. The Young's modulus of the second resin portion (70) is smaller than that of the first resin portion (60). Even if a force that peels the first resin portion (60) and the electrically conductive member (54) away from each other is generated due to a difference in linear expansion coefficient between the first resin portion (60) and the electrically conductive member (54), the second resin portion (70) is ensured to be in close contact with each of the electrically conductive member (54) and the first resin portion (60). Even if the first resin portion (60) and the electrically conductive member (54) are peeled away from each other, the second resin portion (70) is easily elastically deformed following the electrically conductive member (54) and the first resin portion (60). Therefore, the close contact of the second resin portion (70) with each of the electrically conductive member (54) and the first resin portion (60) is maintained. Therefore, the sealing between the first resin portion (60) and the electrically conductive member (54) is ensured by the second resin portion (70).

Description

Technical Field

[0001] This invention relates to centrifugal compressors. Background Technology

[0002] Previously, centrifugal compressors, such as those disclosed in Patent Document 1, were known to include a compressor impeller, a motor, an inverter, and a housing. The compressor impeller compresses the fluid. The motor rotates the compressor impeller. The inverter drives the motor. The housing has a motor chamber and an inverter chamber. The motor chamber houses the motor. The inverter chamber houses the inverter.

[0003] Such a centrifugal compressor includes a conductive component that electrically connects the motor and the converter. A through-hole is formed in the housing for the conductive component to pass through. The through-hole extends through the housing. Furthermore, the centrifugal compressor includes a resin component that holds the conductive component. The resin component is fixed to the housing while holding the conductive component. The resin component seals between itself and the conductive component. Power from the converter is supplied to the motor via the conductive component, thereby driving the motor.

[0004] Existing technical documents

[0005] Patent Document 1: International Publication No. 2017 / 141877 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In such centrifugal compressors, the pressure in the motor chamber is sometimes higher than that in the converter chamber. At this time, due to the difference in the coefficient of linear expansion between the resin components and the conductive components, a force sometimes arises that pulls the resin components and conductive components apart. Consequently, air flowing from the motor chamber into the through-hole may pass between the resin components and the conductive components and enter the converter chamber. If this air enters the converter chamber, condensation may occur due to cooling. Condensation in the converter chamber can adversely affect the converter, potentially reducing the reliability of the centrifugal compressor.

[0008] Technical solutions for solving the problem

[0009] A centrifugal compressor for solving the above-mentioned problems includes: a compressor impeller that compresses a fluid; a motor that rotates the compressor impeller; a converter that drives the motor; a housing having a motor chamber for accommodating the motor and a converter chamber for accommodating the converter; a conductive component that electrically connects the motor and the converter; a through-hole that passes through the housing and allows the conductive component to be inserted; and a resin component that is fixed to the housing while holding the conductive component, and seals between the resin component and the conductive component, wherein the pressure in the motor chamber is higher than the pressure in the converter chamber, wherein the resin component includes: a first resin portion that is fixed to the housing; and a second resin portion that is covered by the first resin portion and covers the conductive component, the resin component having a smaller Young's modulus than the first resin portion, and the first resin portion and the second resin portion, as well as the second resin portion and the conductive component, are joined by insert molding.

[0010] Accordingly, for example, even if a force causing the first resin part and the conductive part to separate due to the difference in the coefficient of linear expansion between the first resin part and the conductive part is generated, the tight adhesion of the second resin part to both the conductive part and the first resin part is ensured. Furthermore, since the Young's modulus of the second resin part is smaller than that of the first resin part, even if the first resin part and the conductive part are separated, the second resin part easily follows the elastic deformation of both the conductive part and the first resin part. Therefore, the tight adhesion of the second resin part to both the conductive part and the first resin part is maintained. Thus, the second resin part ensures a seal between the first resin part and the conductive part, preventing air flowing from the motor chamber into the through-hole from passing between the first resin part and the conductive part and entering the converter chamber. As a result, problems such as condensation in the converter chamber due to cooling of the air entering the converter chamber, which could adversely affect the converter, are avoided. Based on the above, the reliability of the centrifugal compressor can be ensured.

[0011] In the centrifugal compressor described above, the first resin section may be fixed to the outer casing while disposed within the converter chamber.

[0012] Therefore, the first resin section can be prevented from being exposed to high-pressure air in the motor chamber, thus improving the durability of the first resin section. Consequently, the reliability of the centrifugal compressor can be more easily ensured.

[0013] In the centrifugal compressor described above, the conductive component may be plate-shaped, and a through hole extending through the thickness of the conductive component may be formed therein, and the second resin part may have an anchor portion that is locked into the through hole.

[0014] Therefore, by anchoring the second resin part into the through hole, the second resin part can be precisely positioned relative to the conductive component. Thus, the second resin part makes it easier to ensure a seal between the first resin part and the conductive component.

[0015] Invention Effects

[0016] According to the present invention, the reliability of the centrifugal compressor can be ensured. Attached Figure Description

[0017] Figure 1 This is a cross-sectional view of the centrifugal compressor in the implementation method.

[0018] Figure 2 It is a cross-sectional view showing an enlarged portion of a centrifugal compressor.

[0019] Figure 3 This is a cross-sectional view showing the relationship between the conductive component, the first resin part, and the second resin part.

[0020] Figure 4 This is an enlarged cross-sectional view showing a portion of the centrifugal compressor in other embodiments.

[0021] Figure 5 This is a cross-sectional view showing the relationship between the conductive component, the first resin part, and the second resin part.

[0022] Explanation of reference numerals in the attached figures

[0023] 10…Centrifugal compressor, 11…Casing, 34…Compressor impeller, 40…Motor, 50…Transducer, 54…Conductive component, 54h…Through hole, 55…Through hole, 59…Resin component, 60…First resin section, 70…Second resin section, 71…Anchor section, S1…Motor chamber, S3…Transducer chamber. Detailed Implementation

[0024] The following is in accordance with Figures 1-3 An embodiment that embodies a centrifugal compressor will be described. The centrifugal compressor of this embodiment is mounted on a fuel cell vehicle. Furthermore, the centrifugal compressor constitutes part of the fuel cell system mounted on the fuel cell vehicle.

[0025] <Fuel Cell System 1>

[0026] like Figure 1As shown, the fuel cell system 1 includes a fuel cell stack 2 and a centrifugal compressor 10. The centrifugal compressor 10 supplies air as a fluid to the fuel cell stack 2. The fuel cell stack 2 is composed of multiple battery cells (not shown). Each battery cell is constructed by stacking an oxygen electrode, a hydrogen electrode, and an electrolyte membrane disposed between the two electrodes. The fuel cell stack 2 generates electricity by chemically reacting hydrogen, which is used as fuel gas, with oxygen in the air. The fuel cell stack 2 is electrically connected to a driving motor (not shown). The driving motor is driven by the electricity generated by the fuel cell stack 2. The power of the driving motor is transmitted to the axle via a power transmission mechanism (not shown). As a result, the vehicle travels at a speed corresponding to the throttle opening of the accelerator pedal.

[0027] The fuel cell system 1 includes a supply pipe L1, an exhaust pipe L2, and a branch pipe L3. The supply pipe L1 is connected to the supply port 2a of the fuel cell stack 2. The supply pipe L1 supplies air to the fuel cell stack 2. The exhaust pipe L2 is connected to the exhaust port 2b of the fuel cell stack 2. Air from the fuel cell stack 2 is discharged into the exhaust pipe L2.

[0028] Branch pipe L3 branches off from supply pipe L1. A portion of the air flowing in supply pipe L1 branches and flows into branch pipe L3. An intercooler R1 is installed midway through branch pipe L3. Intercooler R1 is configured to cool the air flowing in branch pipe L3.

[0029] Centrifugal Compressor 10

[0030] The centrifugal compressor 10 includes a housing 11. The housing 11 is made of a metal material, such as aluminum. The housing 11 includes a motor housing 12, a compressor housing 13, a turbine housing 14, a first plate 15, a second plate 16, and a sealing plate 17.

[0031] The motor housing 12 is cylindrical. The motor housing 12 has a plate-shaped end wall 12a and a peripheral wall 12b. The peripheral wall 12b extends cylindrically from the outer periphery of the end wall 12a. A first plate 15 is connected to the end of the peripheral wall 12b of the motor housing 12 on the open side. The first plate 15 closes the opening of the peripheral wall 12b of the motor housing 12. Furthermore, the motor chamber S1 is defined by the end wall 12a, the peripheral wall 12b, and the first plate 15 of the motor housing 12. Therefore, the housing 11 has a motor chamber S1.

[0032] On the end face 15a of the first plate 15 opposite to the motor housing 12, a first recess 15c and a second recess 15d are formed. Both the first recess 15c and the second recess 15d are circular holes. The inner diameter of the first recess 15c is larger than the inner diameter of the second recess 15d. The axis of the first recess 15c coincides with the axis of the second recess 15d. The inner circumferential surface of the first recess 15c connects the end face 15a to the bottom surface of the first recess 15c. The inner circumferential surface of the second recess 15d connects the bottom surfaces of the first recess 15c and the second recess 15d.

[0033] The first plate 15 has a first bearing retaining portion 20. The first bearing retaining portion 20 is cylindrical. The first bearing retaining portion 20 protrudes from the center of the end face 15b on the motor housing 12 side of the first plate 15 into the motor chamber S1. The first bearing retaining portion 20 passes through the first plate 15 and opens at the bottom surface of the second recess 15d. The axis of the first bearing retaining portion 20 coincides with the axis of the first recess 15c and the axis of the second recess 15d.

[0034] The motor housing 12 has a second bearing retainer 21. The second bearing retainer 21 is cylindrical. The second bearing retainer 21 protrudes from the center of the inner surface of the end wall 12a of the motor housing 12 into the motor chamber S1. The inner side of the second bearing retainer 21 penetrates the end wall 12a of the motor housing 12 and opens on the outer surface of the end wall 12a. The axis of the first bearing retainer 20 is aligned with the axis of the second bearing retainer 21.

[0035] The second plate 16 is connected to the outer surface of the end wall 12a of the motor housing 12. A shaft insertion through hole 16a is formed in the center of the second plate 16. The shaft insertion through hole 16a communicates with the inner side of the second bearing retaining part 21. The axis of the shaft insertion through hole 16a is aligned with the axis of the second bearing retaining part 21. A shaft insertion through hole 17a is formed in the center of the sealing plate 17. The axis of the shaft insertion through hole 17a is aligned with the axis of the first bearing retaining part 20.

[0036] The sealing plate 17 is installed on the first plate 15 with the first recess 15c embedded in it. The sealing plate 17 closes the opening of the second recess 15d. Furthermore, the thrust bearing receiving chamber S2 is demarcated by the sealing plate 17 and the second recess 15d of the first plate 15.

[0037] The compressor housing 13 is cylindrical. The compressor housing 13 has a circular suction inlet 13a. The compressor housing 13 is connected to the end face 15a of the first plate 15 with the axis of the suction inlet 13a aligned with the axis of the shaft insertion hole 17a of the sealing plate 17 and the axis of the first bearing retaining part 20. The suction inlet 13a opens on the end face of the compressor housing 13 opposite to the first plate 15.

[0038] Within the compressor housing 13, between the suction port 13a and the sealing plate 17, an impeller chamber 13b, a discharge chamber 13c, and a diffusion path 13d are formed. The impeller chamber 13b is connected to the suction port 13a. The discharge chamber 13c extends around the axis of the suction port 13a around the impeller chamber 13b. A supply pipe L1 is connected to the discharge chamber 13c. The diffusion path 13d connects the impeller chamber 13b and the discharge chamber 13c. The impeller chamber 13b is connected to the shaft insertion hole 17a of the sealing plate 17.

[0039] The turbine housing 14 is cylindrical. The turbine housing 14 has a circular outlet 14a. The turbine housing 14 is connected to the end face 16b of the second plate 16 on the side opposite to the motor housing 12, with the axis of the outlet 14a aligned with the axis of the shaft insertion hole 16a of the second plate 16 and the axis of the second bearing retaining part 21. The outlet 14a opens on the end face of the turbine housing 14 on the side opposite to the second plate 16.

[0040] In the turbine housing 14, a turbine chamber 14b, a turbine scroll flow path 14c, and a connecting flow path 14d are formed between the discharge port 14a of the turbine housing 14 and the end face 16b of the second plate 16. Therefore, the housing 11 has a turbine chamber 14b. The turbine chamber 14b is connected to the discharge port 14a. The turbine scroll flow path 14c extends around the axis of the discharge port 14a around the turbine chamber 14b. A discharge pipe L2 is connected to the turbine scroll flow path 14c. The connecting flow path 14d connects the turbine chamber 14b to the turbine scroll flow path 14c. The turbine chamber 14b is connected to the shaft insertion hole 16a.

[0041] The centrifugal compressor 10 includes a rotating body 29. The rotating body 29 has a rotating shaft 30, a first support 31, a second support 32, and a support plate 33. The rotating shaft 30, the first support 31, the second support 32, and the support plate 33 are housed within a housing 11.

[0042] The rotating shaft 30 is housed within the housing 11 with its axial direction aligned with that of the motor housing 12. The first end 30a of the rotating shaft 30 passes through the inner side of the first bearing retaining portion 20, the thrust bearing receiving chamber S2, and the shaft insertion through hole 17a from the motor chamber S1, protruding into the impeller chamber 13b. The second end 30b of the rotating shaft 30 passes through the inner side of the second bearing retaining portion 21 and the shaft insertion through hole 16a from the motor chamber S1, protruding into the turbine chamber 14b.

[0043] A first sealing member 22 is provided between the shaft insertion hole 17a of the sealing plate 17 and the rotating shaft 30. The first sealing member 22 suppresses air leakage from the impeller chamber 13b to the motor chamber S1. A second sealing member 23 is provided between the shaft insertion hole 16a of the second plate 16 and the rotating shaft 30. The second sealing member 23 suppresses air leakage from the turbine chamber 14b to the motor chamber S1. The first sealing member 22 and the second sealing member 23 are, for example, sealing rings.

[0044] The first support portion 31 is provided on the outer peripheral surface of the rotating shaft 30 near the first end 30a. The first support portion 31 is disposed inside the first bearing retaining portion 20. The first support portion 31 is integrally formed on the rotating shaft 30. The first support portion 31 protrudes from the outer peripheral surface of the rotating shaft 30.

[0045] The second support portion 32 is provided on the outer peripheral surface of the rotating shaft 30 near the second end portion 30b. The second support portion 32 is disposed inside the second bearing retaining portion 21. The second support portion 32 is fixed to the outer peripheral surface of the rotating shaft 30 in a ring-shaped manner. The second support portion 32 can rotate integrally with the rotating shaft 30.

[0046] The support plate 33 is housed in the thrust bearing housing S2. The support plate 33 is fixed to the outer circumferential surface of the rotating shaft 30, protruding radially outward in an annular shape. Therefore, the support plate 33 and the rotating shaft 30 are separate. The support plate 33 can rotate integrally with the rotating shaft 30.

[0047] The centrifugal compressor 10 includes a compressor impeller 34. The compressor impeller 34 is mounted at a first end 30a in the axial direction of the rotating shaft 30. The compressor impeller 34 is disposed between a support plate 33 in the rotating shaft 30 and the suction port 13a of the compressor housing 13. The compressor impeller 34 is housed in an impeller chamber 13b. The compressor impeller 34 rotates integrally with the rotating shaft 30.

[0048] The compressor impeller 34 compresses the air drawn in from the suction port 13a within the impeller chamber 13b. Therefore, the compressor impeller 34 compresses the air as a fluid. The air compressed by the compressor impeller 34 then passes through the diffuser path 13d and is discharged into the discharge chamber 13c. The air discharged into the discharge chamber 13c is then discharged into the supply piping L1. The air flowing within the supply piping L1 is supplied to the fuel cell stack 2.

[0049] The centrifugal compressor 10 includes a turbine wheel 35. The turbine wheel 35 is mounted on the second end 30b of the rotating shaft 30. The turbine wheel 35 is positioned between the second support 32 in the rotating shaft 30 and the outlet 14a of the turbine housing 14. The turbine wheel 35 is housed in the turbine chamber 14b. The turbine wheel 35 rotates integrally with the rotating shaft 30. The turbine wheel 35 rotates due to air flowing from the fuel cell stack 2 into the turbine chamber 14b via the discharge pipe L2, the turbine housing flow path 14c, and the connecting flow path 14d.

[0050] The centrifugal compressor 10 includes a first radial bearing 25 and a second radial bearing 26. The first radial bearing 25 is cylindrical and is held in a first bearing retaining portion 20. The second radial bearing 26 is cylindrical and is held in a second bearing retaining portion 21. The first radial bearing 25 and the second radial bearing 26 support the rotating shaft 30 so that it can rotate radially relative to the housing 11. Furthermore, "radial" refers to a direction orthogonal to the axial direction of the rotating shaft 30.

[0051] The centrifugal compressor 10 includes a first thrust bearing 27 and a second thrust bearing 28. The first thrust bearing 27 and the second thrust bearing 28 support the support plate 33 so that it can rotate relative to the housing 11 in the thrust direction. Furthermore, "thrust direction" refers to the direction parallel to the axial direction of the rotation shaft 30.

[0052] The first thrust bearing 27 and the second thrust bearing 28 are housed in the thrust bearing housing S2. The first thrust bearing 27 and the second thrust bearing 28 are configured to sandwich the support plate 33. The first thrust bearing 27 is positioned on the side of the compressor impeller 34 relative to the support plate 33. The second thrust bearing 28 is positioned on the opposite side of the compressor impeller 34 relative to the support plate 33.

[0053] <Motor 40>

[0054] Centrifugal compressor 10 includes a motor 40. The motor 40 is housed in a motor chamber S1. Therefore, the motor chamber S1 houses the motor 40. The motor 40 includes a cylindrical rotor 41 and a cylindrical stator 42. The rotor 41 is fixed to a rotating shaft 30. The stator 42 is fixed to a housing 11. The rotor 41 is arranged radially inside the stator 42 and rotates integrally with the rotating shaft 30. The rotor 41 has a cylindrical rotor core 41a fixed to the rotating shaft 30 and a plurality of permanent magnets (not shown) disposed on the rotor core 41a. The stator 42 surrounds the rotor 41.

[0055] The stator 42 has a cylindrical stator core 43 fixed to the inner circumferential surface of the peripheral wall 12b of the motor housing 12, and a coil 44 wound around the stator core 43. The coil 44 has coil ends 44e protruding from both end faces of the stator core 43. The rotating shaft 30 rotates integrally with the rotor 41 by flowing current to the coil 44 through a battery (not shown). The motor 40 rotates the compressor impeller 34 by rotating the rotating shaft 30. The motor 40 is disposed between the compressor impeller 34 and the vortex impeller 35 in the axial direction of the rotating shaft 30.

[0056] <Import Flow 46>

[0057] The centrifugal compressor 10 has an inlet flow path 46. The inlet flow path 46 is formed on the first plate 15. The inlet flow path 46 extends radially in the direction of the rotating shaft 30. The first end of the inlet flow path 46 opens on the outer surface of the first plate 15. The first end of the inlet flow path 46 is connected to the branch pipe L3. The second end of the inlet flow path 46 is connected to the thrust bearing housing S2.

[0058] A portion of the air compressed by the compressor impeller 34 and flowing in the supply pipe L1 towards the fuel cell stack 2 flows into the inlet flow path 46 via the branch pipe L3. Furthermore, the air flowing into the inlet flow path 46 is cooled by the intercooler R1 midway through its flow in the branch pipe L3. The air flowing into the inlet flow path 46 flows into the thrust bearing housing S2. The air in the thrust bearing housing S2 passes through the inside of the first bearing retainer 20. Then, the air passing through the inside of the first bearing retainer 20 is introduced into the motor chamber S1. Therefore, the inlet flow path 46 introduces a portion of the air compressed by the compressor impeller 34 into the motor chamber S1.

[0059] <Discharge flow path 47>

[0060] The centrifugal compressor 10 includes a discharge passage 47. The discharge passage 47 is formed on the second plate 16. The discharge passage 47 extends radially along the rotating shaft 30. A first end of the discharge passage 47 opens onto the outer surface of the second plate 16. The first end of the discharge passage 47 communicates with the outside. A second end of the discharge passage 47 communicates with a portion of the shaft insertion hole 16a closer to the motor housing 12 than the second sealing member 23. Furthermore, air within the motor chamber S1 passes through the inner side of the second bearing retaining portion 21 and the shaft insertion hole 16a and is discharged to the outside through the discharge passage 47.

[0061] <Converter 50>

[0062] The outer casing 11 has a converter housing 51. The converter housing 51 has a housing body 52 and a cover 53. The housing body 52 has a plate-shaped end wall 52a and a peripheral wall 52b. The peripheral wall 52b extends cylindrically from the outer periphery of the end wall 52a. The cover 53 is plate-shaped. The cover 53 is connected to the housing body 52 with the opening of the peripheral wall 52b closed. Furthermore, the converter chamber S3 is defined by the end wall 52a and peripheral wall 52b of the housing body 52 and the cover 53. Therefore, the outer casing 11 has a converter chamber S3.

[0063] The converter housing 51 is fixed to the motor housing 12 with the outer surface of the housing end wall 52a in contact with the outer peripheral surface of the peripheral wall 12b of the motor housing 12. Therefore, the converter chamber S3 is located radially outside the rotating shaft 30 relative to the motor chamber S1.

[0064] The centrifugal compressor 10 includes a converter 50. The converter 50 is housed in a converter chamber S3. Therefore, the converter chamber S3 houses the converter 50. The converter 50 is located radially outward of the rotating shaft 30 relative to the motor 40. The converter 50 drives the motor 40.

[0065] <Conductive Components 54>

[0066] The centrifugal compressor 10 has conductive components 54. The centrifugal compressor 10 has three conductive components 54. Furthermore, in... Figure 1 The figure shows one of the three conductive components 54. Each conductive component 54 is a plate-shaped bus bar. The first end of each conductive component 54 is electrically connected to one of the three motor wirings 45 leading from the coil end 44e of the coil 44. Furthermore, each motor wiring 45 leads from the coil end 44e protruding from both ends of the stator core 43, located on the side of the compressor impeller 34. The three motor wirings 45 correspond to the U-phase, V-phase, and W-phase of the coil 44, respectively. Each conductive component 54 is electrically connected to the motor wiring 45 in the state corresponding to the U-phase, V-phase, and W-phase of the coil 44, respectively. The second end of each conductive component 54 is electrically connected to the converter 50. Therefore, each conductive component 54 electrically connects the motor 40 to the converter 50.

[0067] <Interceptor Hole 55>

[0068] A first through hole 56 is formed in the peripheral wall 12b of the motor housing 12. The first through hole 56 is formed in the peripheral wall 12b of the motor housing 12 near the first plate 15. The first through hole 56 penetrates the peripheral wall 12b. The first through hole 56 opens at the portion between the stator core 43 and the first plate 15 in the inner peripheral surface of the peripheral wall 12b. The first through hole 56 communicates with the motor chamber S1. Specifically, the first through hole 56 communicates with the portion between the stator core 43 and the first plate 15 in the motor chamber S1.

[0069] A second through hole 57 is formed in the shell end wall 52a. The second through hole 57 penetrates the shell end wall 52a. The first end of the second through hole 57 is connected to the first through hole 56. The second end of the second through hole 57 is connected to the converter chamber S3. Each conductive component 54 passes through the first through hole 56 and the second through hole 57. Therefore, the first through hole 56 and the second through hole 57 form a through hole 55 that penetrates the outer shell 11 and allows each conductive component 54 to be inserted. Therefore, the centrifugal compressor 10 has a through hole 55.

[0070] <Resin Components 59>

[0071] like Figure 2 and Figure 3 As shown, the centrifugal compressor 10 includes a resin component 59. The resin component 59 is fixed to the housing 11 while holding each conductive component 54, and a seal is formed between the resin component 59 and each conductive component 54. The resin component 59 includes a first resin portion 60 and a second resin portion 70.

[0072] <Section 1, Resin 60>

[0073] The first resin portion 60 is a synthetic resin. The first resin portion 60 is a thermoplastic resin. The first resin portion 60 is formed, for example, from polyphenylene sulfide resin (PPS). The first resin portion 60 has a retaining portion 61 and a fixing portion 62.

[0074] The retaining portion 61 covers a portion of each conductive component 54. Specifically, the retaining portion 61 has three retaining holes 63. Furthermore, in Figure 2 The figure shows one of the three retaining holes 63. Each conductive member 54 passes through each retaining hole 63. The inner peripheral surface of each retaining hole 63 is in close contact with the outer surface of each conductive member 54. Furthermore, the retaining portion 61 holds each conductive member 54 through which the retaining hole 63 passes. Therefore, the first resin portion 60 holds each conductive member 54. The first resin portion 60 ensures that adjacent conductive members 54 are insulated from each other. In addition, the retaining portion 61 has a first contact surface 61a. The first contact surface 61a is flat. Each retaining hole 63 opens at the first contact surface 61a.

[0075] The first resin part 60 has two fixing parts 62. Each fixing part 62 is plate-shaped. Each fixing part 62 protrudes from the outer surface of the retaining part 61. Each fixing part 62 has a second contact surface 62a that is continuous with the first contact surface 61a of the retaining part 61. A bolt insertion hole 62h is formed in each fixing part 62. The bolt insertion hole 62h passes through the fixing part 62 in the thickness direction. A bolt 64 can be inserted through the bolt insertion hole 62h. Furthermore, when the first contact surface 61a of the retaining part 61 and the second contact surface 62a of each fixing part 62 are in contact with the inner surface of the shell end wall 52a, each bolt 64 inserted through the bolt insertion hole 62h is screwed into the shell end wall 52a. Thus, the first resin part 60 is fixed to the shell end wall 52a. Therefore, the first resin part 60 is fixed to the outer casing 11 while retaining each conductive component 54. Therefore, the first resin part 60 is fixed to the outer casing 11 while it is disposed in the converter chamber S3.

[0076] <Washer 65>

[0077] The centrifugal compressor 10 includes a gasket 65. The gasket 65 is annular. The gasket 65 is, for example, made of rubber. The gasket 65 is disposed on the outer periphery of the first contact surface 61a. The gasket 65 extends along the outer periphery of the first contact surface 61a. The gasket 65 is mounted on the first contact surface 61a in a manner that surrounds three retaining holes 63. The gasket 65 seals between the first resin portion 60 and the housing end wall 52a. The gasket 65 prevents air flowing from the motor chamber S1 into the through hole 55 from entering the converter chamber S3 through the space between the first resin portion 60 and the housing end wall 52a.

[0078] <Section 2, Resin 70>

[0079] The resin component 59 includes three second resin portions 70. Each second resin portion 70 is formed of a thermoplastic polyester elastomer. The second resin portion 70 is Hytrel (registered trademark). Therefore, each second resin portion 70 is formed of a material with rubber elasticity. The Young's modulus of the second resin portion 70 is smaller than that of the first resin portion 60.

[0080] Each second resin portion 70 is annular. Each second resin portion 70 covers a portion of each conductive member 54 in a surrounding manner. Each second resin portion 70 covers each conductive member 54. Each second resin portion 70 is disposed between each retaining hole 63 and each conductive member 54. The inner peripheral surface of each second resin portion 70 is in close contact with the outer surface of each conductive member 54. The outer peripheral surface of each second resin portion 70 is in close contact with the inner peripheral surface of each retaining hole 63. Furthermore, each second resin portion 70 seals between each conductive member 54 and each retaining hole 63. Therefore, each second resin portion 70 seals between the first resin portion 60 and each conductive member 54. Each second resin portion 70 is covered by the first resin portion 60.

[0081] Compared to the force that causes the first resin portion 60 to peel away from each conductive component 54 due to the difference in the coefficient of linear expansion between the first resin portion 60 and each conductive component 54, the adhesion force of each second resin portion 70 relative to each conductive component 54 and each first resin portion 60 is higher. The Young's modulus of the second resin portion 70 is smaller than that of the first resin portion 60.

[0082] The first resin portion 60 and each of the second resin portions 70 are integrated with each conductive component 54 through insert molding. Specifically, firstly, a one-time molding process is performed on each conductive component 54 to insert the second resin portions 70. This integrates each second resin portion 70 with each conductive component 54. Next, a second molding process is performed on each conductive component 54 with the integrated second resin portions 70 to insert the first resin portion 60. This integrates the first resin portion 60 with each conductive component 54. In this way, the first resin portion 60 and each of the second resin portions 70, as well as each of the second resin portions 70 and each conductive component 54, are bonded together through insert molding.

[0083] [The Role of the Implementation Method]

[0084] Next, the function of this embodiment will be explained.

[0085] A portion of the air compressed by the compressor impeller 34 flows into the thrust bearing housing S2 via the inlet flow path 46. The first thrust bearing 27 and the second thrust bearing 28 are cooled by the air flowing into the thrust bearing housing S2 from the inlet flow path 46. The air in the thrust bearing housing S2 flows towards the inside of the first bearing retainer 20. The first radial bearing 25 is cooled by the air passing through the inside of the first bearing retainer 20.

[0086] Air passing through the inside of the first bearing retainer 20 is introduced into the motor chamber S1. The motor 40 is cooled by the air introduced into the motor chamber S1. Air in the motor chamber S1 flows into the inside of the second bearing retainer 21. The second radial bearing 26 is cooled by the air passing through the inside of the second bearing retainer 21. The air passing through the inside of the second bearing retainer 21 passes through the shaft insertion hole 16a and is discharged to the outside through the discharge passage 47. In this way, the first thrust bearing 27, the second thrust bearing 28, the first radial bearing 25, the motor 40, and the second radial bearing 26 are cooled by a portion of the air compressed by the compressor impeller 34.

[0087] Air passing through fuel cell stack 2 is discharged to exhaust pipe L2 as exhaust from fuel cell stack 2. Air from fuel cell stack 2 is discharged to turbine chamber 14b via exhaust pipe L2, turbine volute flow path 14c, and connecting flow path 14d. The vortex impeller 35 rotates due to the air discharged to turbine chamber 14b. In addition to the rotation driven by motor 40, the rotating shaft 30 also rotates according to the rotation of the vortex impeller 35 driven by the air discharged to turbine chamber 14b. Furthermore, the rotation of the rotating shaft 30 is assisted by the rotation of the vortex impeller 35 driven by the air discharged to turbine chamber 14b. Air passing through turbine chamber 14b is discharged to the outside from exhaust port 14a.

[0088] Because a portion of the air compressed by the compressor impeller 34 is introduced into the motor chamber S1, the pressure inside the motor chamber S1 is higher than the pressure inside the converter chamber S3. Furthermore, sometimes air from the impeller chamber 13b also flows into the motor chamber S1 through the shaft insertion hole 17a, the thrust bearing housing S2, and the inner side of the first bearing retainer 20. Under these circumstances, the pressure inside the motor chamber S1 also becomes higher than the pressure inside the converter chamber S3.

[0089] In this way, the centrifugal compressor 10 sometimes operates under conditions where the pressure in the motor chamber S1 is higher than the pressure in the converter chamber S3. At this time, due to the difference between the linear expansion coefficient of the first resin section 60 and the linear expansion coefficient of each conductive component 54, a force sometimes arises that pulls the first resin section 60 and each conductive component 54 apart. As a result, air flowing from the motor chamber S1 into the through hole 55 attempts to pass through the gap between the first resin section 60 and each conductive component 54 and enter the converter chamber S3.

[0090] At this time, the first resin portion 60 is bonded to each of the second resin portions 70, and each of the second resin portions 70 is bonded to each of the conductive components 54, by insert molding. Furthermore, compared to the force that would cause the first resin portion 60 to peel away from each of the conductive components 54 due to the difference in the coefficient of linear expansion between the first resin portion 60 and the conductive components 54, the adhesion force of each of the second resin portions 70 to each of the conductive components 54 and the first resin portion 60 is higher. Therefore, even if a force causes the first resin portion 60 to peel away from each of the conductive components 54 due to the difference in the coefficient of linear expansion between the first resin portion 60 and the conductive components 54, the tight adhesion of each of the second resin portions 70 to each of the conductive components 54 and the first resin portion 60 is ensured.

[0091] Furthermore, since the Young's modulus of each second resin portion 70 is smaller than that of the first resin portion 60, even if the first resin portion 60 and each conductive component 54 are peeled off from each other, each second resin portion 70 can easily elastically deform along with each conductive component 54 and the first resin portion 60. Therefore, the tight fit between each second resin portion 70 and each conductive component 54 is maintained. Thus, the sealing between the first resin portion 60 and each conductive component 54 is ensured by each second resin portion 70. As a result, air flowing from the motor chamber S1 into the insertion hole 55 is prevented from passing between the first resin portion 60 and each conductive component 54 and entering the converter chamber S3.

[0092] [Effects of the Implementation Method]

[0093] The following effects can be obtained from the above embodiments.

[0094] (1) The first resin portion 60 and each of the second resin portions 70, as well as each of the second resin portions 70 and each conductive member 54, are joined by insert molding. Therefore, even if a force arises that causes the first resin portion 60 and the conductive member 54 to separate due to the difference in the coefficient of linear expansion between the first resin portion 60 and the conductive member 54, the tight fit of the second resin portion 70 with respect to both the conductive member 54 and the first resin portion 60 is ensured. Furthermore, since the Young's modulus of the second resin portion 70 is smaller than that of the first resin portion 60, even if the first resin portion 60 and the conductive member 54 are separated, the second resin portion 70 easily follows the elastic deformation of the conductive member 54 and the first resin portion 60. Therefore, the tight fit of the second resin portion 70 with respect to both the conductive member 54 and the first resin portion 60 is maintained. Thus, the sealing between the first resin portion 60 and the conductive member 54 can be ensured by the second resin portion 70. Therefore, it is possible to prevent air flowing from the motor chamber S1 into the insertion hole 55 from passing between the first resin section 60 and the conductive member 54 and entering the converter chamber S3. As a result, it is possible to avoid the problem of condensation occurring in the converter chamber S3 due to the cooling of the air entering the converter chamber S3, which could adversely affect the converter 50. Based on the above, the reliability of the centrifugal compressor 10 can be ensured.

[0095] (2) The first resin section 60 is fixed to the outer casing 11 while being disposed within the converter chamber S3. This prevents the first resin section 60 from being exposed to the high-pressure air within the motor chamber S1, thus improving the durability of the first resin section 60. Therefore, it is easier to ensure the reliability of the centrifugal compressor 10.

[0096] (3) With the first resin part 60 disposed within the converter chamber S3, it is fixed to the end wall 52a of the converter housing 51 by bolts 64. Therefore, it is possible to construct an assembly in which the resin part 59 holding the conductive member 54 is integrally formed with the converter housing 51. Furthermore, with the resin part 59 holding the conductive member 54 fixed to the converter housing 51, the converter housing 51 can be assembled to the motor housing 12, thus improving assembly operability.

[0097] [Variation Example]

[0098] Furthermore, the above-described embodiments can be implemented with modifications as follows. The above-described embodiments and the following modifications can be combined with each other to implement them without technical inconsistencies.

[0099] ο can also be, such as Figure 4 and Figure 5 As shown, each conductive component 54 has a through hole 54h extending through the thickness of the conductive component 54, and each second resin portion 70 has an anchor portion 71 that is engaged with the through hole 54h. Each second resin portion 70 has a sealing body portion 70a and an anchor portion 71. The sealing body portion 70a is annular around the conductive component 54. The anchor portion 71 is columnar and disposed inside the through hole 54h. The anchor portion 71 is integrally formed with the sealing body portion 70a. The outer peripheral surface of the anchor portion 71 is in close contact with the inner peripheral surface of the through hole 54h.

[0100] Accordingly, by anchoring the second resin portion 70 to the through hole 54h, the second resin portion 70 can be precisely positioned relative to the conductive member 54. Therefore, the second resin portion 70 makes it easier to ensure a seal between the first resin portion 60 and the conductive member 54. Furthermore, when the second resin portion 70 is inserted into the conductive member 54, misalignment between the second resin portion 70 and the conductive member 54 due to injection pressure can be prevented.

[0101] In one embodiment, for example, a notch may be formed on the side of each conductive component 54, and the second resin portion 70 may have an anchor portion that engages with the notch. In such a case, it is also possible to achieve... Figure 4 and Figure 5 As shown in the embodiment, the second resin portion 70 is positioned with good precision relative to the conductive component 54.

[0102] In one embodiment, the first resin portion 60 may be formed, for example, of polybutylene terephthalate resin (PBT) or polycarbonate resin (PC).

[0103] In one embodiment, the resin component 59 has three second resin portions 70, but is not limited thereto. For example, it may also be configured to have one second resin portion that surrounds the three conductive components 54 together.

[0104] In one embodiment, the first resin portion 60 may be fixed to the housing 11 while disposed within the motor chamber S1. For example, the first resin portion 60 may also be fixed to the inner circumferential surface of the peripheral wall 12b of the motor housing 12.

[0105] In one embodiment, for example, a cooling fluid other than the air compressed by the compressor impeller 34 may be introduced into the motor chamber S1.

[0106] In one embodiment, the centrifugal compressor 10 may also be configured not to have a vortex impeller 35.

[0107] In one embodiment, the centrifugal compressor 10 may be configured to have a compressor impeller instead of the vortex impeller 35. That is, it may also be configured such that compressor impellers are installed at both ends of the rotating shaft 30, and the fluid compressed by one compressor impeller is compressed again by the other compressor impeller.

[0108] In some embodiments, the fuel cell system 1 may be installed outside the fuel cell vehicle. Therefore, the centrifugal compressor 10 is not limited to being installed in a fuel cell vehicle, and the application of the centrifugal compressor 10 may be appropriately changed.

[0109] In some embodiments, the centrifugal compressor 10 may also be used, for example, in a vehicle air conditioning system. Therefore, the fluid compressed by the compressor impeller 34 is not limited to air; it may also be a refrigerant, for example.

Claims

1. A centrifugal compressor, characterized in that, have: The compressor impeller compresses the fluid; A motor that rotates the compressor impeller; A converter that drives the motor; The housing has a motor chamber for housing the motor and a converter chamber for housing the converter; A conductive component that electrically connects the motor to the converter; A through-hole that penetrates the housing and allows the conductive component to be inserted; and A resin component, which is fixed to the housing while retaining the conductive component, and a seal is formed between the resin component and the conductive component. The pressure inside the motor chamber is higher than the pressure inside the converter chamber. The resin component includes: The first resin part, which is fixed to the outer casing when disposed in the converter chamber; and A second resin portion, which is covered by the first resin portion and covers the conductive component, has a smaller Young's modulus than the first resin portion. The first resin portion covers the second resin portion in such a manner that it completely surrounds the second resin portion. The first resin portion and the second resin portion, as well as the second resin portion and the conductive component, are joined by insert molding.

2. The centrifugal compressor according to claim 1, characterized in that, The conductive component is plate-shaped. A through hole is formed in the conductive component, extending through the thickness direction of the conductive component. The second resin part has an anchor portion that is locked into the through hole.

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