Electric Compressor

Abstract

To improve corrosion resistance of an electric compressor.SOLUTION: An annular seal member 50 is provided between an inner peripheral surface of a seal peripheral wall 28 and an outer peripheral surface of a housing peripheral wall 15. The seal member 50 extends in a radial direction between a case end surface 29 and a housing confronting surface 41. Accordingly, for example, moisture or salt water dammed up by the seal member 50 is restrained from staying between the case end surface 29 and the housing confronting surface 41.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an electric compressor. [Background technology]

[0002] The electric compressor includes a rotating shaft, an electric motor that rotates the rotating shaft, a compression section that is driven by the rotation of the rotating shaft to compress a fluid, and an inverter that drives the electric motor. The electric compressor also includes a cylindrical housing that accommodates the electric motor. The housing has a housing end wall and a housing peripheral wall. The housing peripheral wall extends from the housing end wall in the axial direction of the rotating shaft. For example, as in Patent Document 1, the electric compressor also includes a cylindrical inverter case that accommodates the inverter. The inverter case is fixed to the housing. The inverter case has a case end wall and a seal peripheral wall. The case end wall faces the housing end wall in the axial direction of the rotating shaft. The seal peripheral wall extends from the case end wall in the axial direction of the rotating shaft. The seal peripheral wall surrounds a part of the outer circumferential surface of the housing peripheral wall. An annular seal member is provided between the inner circumferential surface of the seal peripheral wall and the outer circumferential surface of the housing peripheral wall. The seal member seals between the inner peripheral surface of the seal peripheral wall and the outer peripheral surface of the housing peripheral wall, thereby preventing, for example, moisture or salt water from entering between the inner peripheral surface of the seal peripheral wall and the outer peripheral surface of the housing peripheral wall from the outside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-165423 A Summary of the Invention [Problem to be solved by the invention]

[0004] The seal peripheral wall has an end face at an end in a direction extending from the case end wall. The housing peripheral wall may have an opposing surface that faces the end face of the seal peripheral wall in the axial direction of the rotating shaft. In this case, moisture or salt water blocked by the seal member may accumulate between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall. If moisture or salt water accumulates between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall in this way, there is a risk that the housing or the inverter case will be corroded by the moisture or salt water. [Means for solving the problem]

[0005] The electric compressor that solves the above problem includes a rotating shaft, an electric motor that rotates the rotating shaft, a compression section that is driven by the rotation of the rotating shaft to compress a fluid, an inverter that drives the electric motor, a cylindrical housing that has a housing end wall and a housing peripheral wall extending from the housing end wall in the axial direction of the rotating shaft and that accommodates the electric motor, and a cylindrical inverter case that accommodates the inverter and is fixed to the housing, and the inverter case has a housing end wall that is axially extended from the housing end wall to the axial direction of the rotating shaft. the housing peripheral wall has an opposing surface opposed to the inner surface of the seal peripheral wall, and a seal peripheral wall extending from the case end wall in the axial direction of the rotating shaft and surrounding a part of the outer peripheral surface of the housing peripheral wall, the seal peripheral wall having an end face at an end in the direction extending from the case end wall, the housing peripheral wall having an opposing surface opposed to the end face in the axial direction of the rotating shaft, and an annular seal member is provided between the inner peripheral surface of the seal peripheral wall and the outer peripheral surface of the housing peripheral wall, and the seal member extends in the radial direction of the rotating shaft between the end face and the opposing surface.

[0006] According to this, since the seal member extends between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall in the radial direction of the rotating shaft, for example, it is possible to prevent moisture or salt water blocked by the seal member from accumulating between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall, thereby improving the corrosion resistance of the electric compressor.

[0007] In the above electric compressor, a motor accommodating chamber for accommodating the electric motor is defined inside the housing peripheral wall, and an intake port is formed in the housing peripheral wall which connects the outside to the motor accommodating chamber and draws the refrigerant as the fluid into the housing from the outside, and a portion of the sealing member extends from between the end face and the opposing surface to the outside of the housing.

[0008] The housing is cooled by the refrigerant drawn into the housing from the outside through the suction port, and the cooling of the housing also cools the seal member, which may result in the seal member shrinking. Even in this case, a part of the seal member extends from between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall to the outside of the housing, so that it is possible to prevent a gap from being generated between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall. Therefore, for example, it is possible to prevent moisture or salt water blocked by the seal member from accumulating between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall.

[0009] In the above electric compressor, it is preferable that a ring-shaped conductor is integrally provided on the sealing member, and the conductor is disposed between the end face and the opposing surface. According to this, electromagnetic noise attempting to pass between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall can be shielded by the conductor, thereby preventing external electromagnetic noise from passing between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall and entering the inside of the electric compressor, and preventing electromagnetic noise from inside the electric compressor from passing between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall and leaking to the outside.

[0010] In the electric compressor, the conductor may be sandwiched between the end surface and the opposing surface. According to this, since the conductor is sandwiched between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall, the portion of the seal member located between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall can be accurately positioned between the end face of the seal peripheral wall and the opposing surface of the housing peripheral wall, thereby improving the sealing performance between the end face of the seal peripheral wall of the seal member and the opposing surface of the housing peripheral wall. Effect of the Invention

[0011] According to the present invention, the corrosion resistance of the electric compressor can be improved. [Brief description of the drawings]

[0012] [Figure 1] 1 is a side cross-sectional view of a motor-driven compressor according to an embodiment, with a portion cut away; [Diagram 2] FIG. 2 is an enlarged cross-sectional view of a portion of the electric compressor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] An embodiment of an electric compressor will now be described with reference to Figures 1 and 2. The electric compressor of this embodiment is used in, for example, a vehicle air conditioner. (Overall configuration of electric compressor 10) As shown in FIG. 1, the electric compressor 10 includes a cylindrical housing 11. The housing 11 is made of metal. The housing 11 includes a discharge housing 12 and a motor housing 13. The discharge housing 12 and the motor housing 13 are made of, for example, aluminum. The discharge housing 12 is connected to the motor housing 13. The motor housing 13 includes a plate-shaped housing end wall 14 and a housing peripheral wall 15 extending cylindrically from the outer periphery of the housing end wall 14. The housing peripheral wall 15 is formed with a suction port 16 for drawing a refrigerant as a fluid into the motor housing 13 from the outside. Thus, the housing 11 includes the suction port 16.

[0014] The electric compressor 10 includes a compression section 17 that compresses the refrigerant, an electric motor 18 that drives the compression section 17, and an inverter 19 that drives the electric motor 18. The electric compressor 10 also includes a rotating shaft 20. The rotating shaft 20 is accommodated in the motor housing 13. The rotating shaft 20 is accommodated in the motor housing 13 with the axis of the rotating shaft 20 coinciding with the axis of the housing peripheral wall 15. Therefore, the housing peripheral wall 15 extends in the axial direction of the rotating shaft 20.

[0015] The compression section 17 and the electric motor 18 are accommodated in the motor housing 13. Specifically, a motor accommodating chamber 15a that accommodates the electric motor 18 is defined inside the housing peripheral wall 15. Thus, the housing 11 accommodates the electric motor 18. The compression section 17 and the electric motor 18 are arranged side by side in the axial direction of the rotating shaft 20. The electric motor 18 is arranged closer to the housing end wall 14 than the compression section 17. The electric motor 18 rotates the rotating shaft 20. The compression section 17 is driven by the rotation of the rotating shaft 20 to compress the refrigerant.

[0016] The compression section 17 is, for example, of a scroll type including a fixed scroll (not shown) fixed inside the motor housing 13 and a movable scroll (not shown) disposed opposite the fixed scroll.

[0017] The electric motor 18 is composed of a cylindrical stator 21 and a rotor 22 arranged inside the stator 21. The rotor 22 rotates integrally with the rotating shaft 20. The stator 21 surrounds the rotor 22. The rotor 22 has a rotor core 22a fixed to the rotating shaft 20 and a plurality of permanent magnets (not shown) provided on the rotor core 22a. The stator 21 has a cylindrical stator core 21a and a motor coil 21b wound around the stator core 21a.

[0018] One end of an external refrigerant circuit 23 is connected to the suction port 16. A discharge port 12a is formed in the discharge housing 12. The other end of the external refrigerant circuit 23 is connected to the discharge port 12a. The suction port 16 communicates the outside with the motor housing chamber 15a. The refrigerant sucked from the external refrigerant circuit 23 into the motor housing chamber 15a of the motor housing 13 through the suction port 16 is compressed in the compression section 17 by driving the compression section 17, and flows out to the external refrigerant circuit 23 through the discharge port 12a. The refrigerant that flows out to the external refrigerant circuit 23 flows through a heat exchanger and an expansion valve (not shown) of the external refrigerant circuit 23, and returns to the motor housing 13 through the suction port 16. The electric compressor 10 and the external refrigerant circuit 23 constitute a vehicle air conditioner 24.

[0019] (Configuration of inverter case 25) The electric compressor 10 includes a cylindrical inverter case 25. The inverter case 25 houses the inverter 19. The inverter case 25 has a plate-shaped case end wall 26 and a case peripheral wall 27 extending cylindrically from the outer periphery of the case end wall 26. The case end wall 26 faces the housing end wall 14 in the axial direction of the rotating shaft 20. The inverter case 25 is fixed to the motor housing 13 by attaching the case end wall 26 to the housing end wall 14. Therefore, the inverter case 25 is fixed to the housing 11. In this embodiment, the compression unit 17, the electric motor 18, and the inverter 19 are arranged in this order in the axial direction of the rotating shaft 20.

[0020] As shown in FIG. 2, the inverter case 25 has a seal peripheral wall 28. The seal peripheral wall 28 extends cylindrically from the outer periphery of the case end wall 26 toward the opposite side to the case peripheral wall 27. The seal peripheral wall 28 extends from the case end wall 26 in the axial direction of the rotating shaft 20. The inner periphery of the seal peripheral wall 28 extends along the outer periphery of the housing peripheral wall 15. The seal peripheral wall 28 surrounds a part of the outer periphery of the housing peripheral wall 15. The seal peripheral wall 28 has a case end face 29 which is the end face of the seal peripheral wall 28 on the opposite side to the case end wall 26. The case end face 29 is the end face at the end in the direction extending from the case end wall 26.

[0021] (Electrical connection between electric motor 18 and inverter 19) As shown in Fig. 1, the electric compressor 10 has a through hole 30 penetrating the housing end wall 14 and the case end wall 26. The electric compressor 10 also has three conductive members 31. For convenience of explanation, only one conductive member 31 is shown in Fig. 1. Each conductive member 31 is supported by the case end wall 26 via a support plate 32.

[0022] Each conductive member 31 is electrically connected to the inverter 19. Each conductive member 31 passes through a through hole 30 from inside the inverter case 25 and protrudes into the motor housing 13. Each conductive member 31 is electrically connected to each motor wire 34 drawn from the electric motor 18 via a cluster block 33 arranged in the motor housing 13. This electrically connects the electric motor 18 and the inverter 19 via the motor wires 34, the cluster block 33, and each conductive member 31. Electric power is supplied from the inverter 19 to the electric motor 18 via the conductive members 31, the cluster block 33, and each motor wire 34, thereby driving the electric motor 18.

[0023] (Configuration of housing peripheral wall 15) 2, the outer circumferential surface of the housing peripheral wall 15 has a first housing outer circumferential surface 40, a housing opposing surface 41, and a second housing outer circumferential surface 42. The first housing outer circumferential surface 40 is a portion of the outer circumferential surface of the housing peripheral wall 15 that is surrounded by the seal peripheral wall 28. The first housing outer circumferential surface 40 is cylindrical and extends in the axial direction of the housing peripheral wall 15. An edge of the first housing outer circumferential surface 40 on the inverter case 25 side faces the case end wall 26 of the inverter case 25 in the axial direction of the housing peripheral wall 15.

[0024] The housing opposing surface 41 is an opposing surface on the outer circumferential surface of the housing peripheral wall 15 that faces the case end surface 29 in the axial direction of the rotating shaft 20. The housing opposing surface 41 extends in an annular shape from an edge located on the opposite side of the first housing outer circumferential surface 40 to the case end wall 26 of the inverter case 25 toward the outside in the radial direction of the rotating shaft 20. The housing opposing surface 41 is a flat surface.

[0025] The second housing outer peripheral surface 42 is cylindrical and extends in the axial direction of the housing peripheral wall 15. The second housing outer peripheral surface 42 extends from an outer peripheral edge located on the opposite side of the housing opposing surface 41 from the first housing outer peripheral surface 40 toward the opposite side of the inverter case 25. Therefore, the housing opposing surface 41 connects the first housing outer peripheral surface 40 and the second housing outer peripheral surface 42. The housing opposing surface 41 is an annular stepped surface extending in the radial direction of the rotating shaft 20 between the first housing outer peripheral surface 40 and the second housing outer peripheral surface 42. The outer diameter of the second housing outer peripheral surface 42 is larger than the outer diameter of the first housing outer peripheral surface 40. The outer diameter of the second housing outer peripheral surface 42 is smaller than the outer diameter of the seal peripheral wall 28.

[0026] (Configuration of seal member 50) The electric compressor 10 includes an annular seal member 50. The seal member 50 is provided between the inner circumferential surface of the seal peripheral wall 28 and the outer circumferential surface of the housing peripheral wall 15. The seal member 50 has a first seal portion 51 and a second seal portion 52. The first seal portion 51 is cylindrical. The second seal portion 52 is annular flange-shaped and extends outward from the first seal portion 51.

[0027] The first seal portion 51 is disposed between the inner peripheral surface of the seal peripheral wall 28 and the first housing outer peripheral surface 40 of the housing peripheral wall 15. The first seal portion 51 is sandwiched between the inner peripheral surface of the seal peripheral wall 28 and the first housing outer peripheral surface 40 of the housing peripheral wall 15. The outer peripheral portion of the first seal portion 51 is in close contact with the inner peripheral surface of the seal peripheral wall 28. The inner peripheral portion of the first seal portion 51 is in close contact with the first housing outer peripheral surface 40 of the housing peripheral wall 15. Therefore, the first seal portion 51 seals between the inner peripheral surface of the seal peripheral wall 28 and the first housing outer peripheral surface 40 of the housing peripheral wall 15. Therefore, in the electric compressor 10, the gap between the inner peripheral surface of the seal peripheral wall 28 and the outer peripheral surface of the housing peripheral wall 15 is sealed by the seal member 50.

[0028] A majority of the second seal portion 52 is disposed between the case end face 29 and the housing opposing surface 41. A majority of the second seal portion 52 is sandwiched between the case end face 29 and the housing opposing surface 41. A portion of the second seal portion 52 facing the case end face 29 is in close contact with the case end face 29. A portion of the second seal portion 52 facing the housing opposing surface 41 is in close contact with the housing opposing surface 41. Thus, the second seal portion 52 provides a seal between the case end face 29 and the housing opposing surface 41. The seal member 50 extends in the radial direction of the rotating shaft 20 between the case end face 29 and the housing opposing surface 41.

[0029] An end of the second seal portion 52 opposite to the first seal portion 51 protrudes from between the case end face 29 and the housing opposing surface 41. The portion of the second seal portion 52 protruding from between the case end face 29 and the housing opposing surface 41 extends along the case end face 29, and a portion of it bulges toward the second housing outer peripheral surface 42. Therefore, a portion of the seal member 50 extends from between the case end face 29 and the housing opposing surface 41 to the outside of the housing 11. A portion of the seal member 50 is exposed to the outside of the housing 11 from between the case end face 29 and the housing opposing surface 41.

[0030] (Configuration of conductor 55) The seal member 50 is provided integrally with an annular conductor 55. The conductor 55 is made of metal. The seal member 50 and the conductor 55 are integrated by insert molding. The conductor 55 is disposed between the case end face 29 and the housing facing surface 41. The conductor 55 is in contact with the case end face 29. Thus, the conductor 55 is electrically connected to the seal peripheral wall 28. The conductor 55 is in contact with the housing facing surface 41. Thus, the conductor 55 is electrically connected to the housing peripheral wall 15 of the motor housing 13. The conductor 55 is sandwiched between the case end face 29 and the housing facing surface 41. The inner diameter of the conductor 55 is larger than the inner diameter of the seal peripheral wall 28. The outer diameter of the conductor 55 is the same as the outer diameter of the second housing outer circumferential surface 42.

[0031] (action) Next, the operation of this embodiment will be described. For example, moisture or salt water that tries to infiltrate from the outside between the inner circumferential surface of the seal peripheral wall 28 and the outer circumferential surface of the housing peripheral wall 15 is blocked by the seal member 50. Therefore, moisture or salt water is prevented from infiltrating toward the through hole 30 through the gap between the inner circumferential surface of the seal peripheral wall 28 and the outer circumferential surface of the housing peripheral wall 15. As a result, a problem that moisture or salt water from the outside comes into contact with the conductive member 31 is avoided. In addition, the seal member 50 extends in the radial direction of the rotating shaft 20 between the case end surface 29 and the housing facing surface 41. Therefore, for example, moisture or salt water blocked by the seal member 50 is prevented from accumulating between the case end surface 29 and the housing facing surface 41.

[0032] Furthermore, the conductor 55 is disposed between the case end face 29 and the housing opposing surface 41. Thus, electromagnetic noise attempting to pass between the case end face 29 and the housing opposing surface 41 is shielded by the conductor 55. This prevents external electromagnetic noise from passing between the case end face 29 and the housing opposing surface 41 and entering the inside of the electric compressor 10, and prevents electromagnetic noise from inside the electric compressor 10 from passing between the case end face 29 and the housing opposing surface 41 and leaking to the outside.

[0033] (effect) The above embodiment can provide the following advantageous effects. (1) Since the seal member 50 extends between the case end face 29 and the housing opposing surface 41 in the radial direction of the rotating shaft 20, for example, it is possible to prevent moisture or salt water blocked by the seal member 50 from accumulating between the case end face 29 and the housing opposing surface 41. This makes it possible to improve the corrosion resistance of the electric compressor 10.

[0034] (2) The motor housing 13 is cooled by the refrigerant drawn into the motor housing 13 from the outside through the suction port 16, and the cooling of the motor housing 13 also cools the seal member 50, which may result in the seal member 50 contracting. Even in this case, a portion of the seal member 50 extends from between the case end face 29 and the housing opposing surface 41 to the outside of the housing 11, so that it is possible to prevent a gap from being generated between the case end face 29 and the housing opposing surface 41. Therefore, for example, it is possible to prevent moisture or salt water blocked by the seal member 50 from accumulating between the case end face 29 and the housing opposing surface 41.

[0035] (3) The conductor 55 is disposed between the case end face 29 and the housing opposing surface 41. This allows the conductor 55 to block electromagnetic noise attempting to pass between the case end face 29 and the housing opposing surface 41. This makes it possible to prevent external electromagnetic noise from passing between the case end face 29 and the housing opposing surface 41 and entering the inside of the electric compressor 10, and to prevent electromagnetic noise from inside the electric compressor 10 from passing between the case end face 29 and the housing opposing surface 41 and leaking to the outside.

[0036] (4) The conductor 55 is sandwiched between the case end face 29 and the housing opposing surface 41. As a result, the conductor 55 is sandwiched between the case end face 29 and the housing opposing surface 41, and thus the portion of the seal member 50 located between the case end face 29 and the housing opposing surface 41 can be accurately positioned between the case end face 29 and the housing opposing surface 41. This improves the sealing performance of the seal member 50 between the case end face 29 and the housing opposing surface 41.

[0037] (Example of change) The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0038] In the above embodiment, a portion of the seal member 50 does not have to extend from between the case end surface 29 and the housing opposing surface 41 to the outside of the housing 11 . In the embodiment, the conductor 55 does not have to be sandwiched between the case end surface 29 and the housing opposing surface 41. In this case, the conductor 55 may be disposed between the case end surface 29 and the housing opposing surface 41, for example, in a state where the conductor 55 is spaced apart from both the case end surface 29 and the housing opposing surface 41.

[0039] In the above embodiment, the conductor 55 does not have to be disposed between the case end surface 29 and the housing opposing surface 41, and the annular conductor 55 does not have to be integrally formed with the seal member 50.

[0040] In the above embodiment, the outer diameter of the conductor 55 may be smaller than the outer diameter of the second housing outer peripheral surface 42 , or the outer diameter of the conductor 55 may be larger than the outer diameter of the second housing outer peripheral surface 42 .

[0041] In the above embodiment, the case end surface 29 and the housing opposing surface 41 may extend in a stepped shape corresponding to each other, and the seal member 50 may extend in a stepped shape between the case end surface 29 and the housing opposing surface 41 .

[0042] In the above-mentioned embodiment, the compression section 17 is not limited to a scroll type, and may be, for example, a piston type or a vane type. In the embodiment, the electric compressor 10 constitutes the vehicle air conditioning device 24. However, the present invention is not limited to this. For example, the electric compressor 10 may be mounted on a fuel cell vehicle and compress air, which is a fluid supplied to the fuel cell, by the compression unit 17. [Explanation of symbols]

[0043] 10...electric compressor, 11...housing, 14...housing end wall, 15...housing peripheral wall, 15a...motor accommodating chamber, 16...suction port, 17...compression section, 18...electric motor, 19...inverter, 20...rotating shaft, 25...inverter case, 26...case end wall, 28...seal peripheral wall, 29...case end surface which is end face, 41...housing opposing surface which is opposing surface, 50...sealing member, 55...conductor.

Claims

1. A rotation axis; an electric motor that rotates the rotary shaft; a compression section that is driven by rotation of the rotary shaft and compresses a fluid; an inverter that drives the electric motor; a cylindrical housing having a housing end wall and a housing peripheral wall extending from the housing end wall in an axial direction of the rotary shaft and accommodating the electric motor; a cylindrical inverter case that accommodates the inverter and is fixed to the housing, The inverter case is a case end wall facing the housing end wall in the axial direction of the rotary shaft; a seal peripheral wall extending from the case end wall in the axial direction of the rotary shaft and surrounding a portion of an outer circumferential surface of the housing peripheral wall, the peripheral seal wall has an end surface at an end in a direction extending from the case end wall, the housing peripheral wall has an opposing surface that faces the end surface in the axial direction of the rotation shaft, A motor accommodating chamber for accommodating the electric motor is defined inside the housing peripheral wall, a suction port formed in the housing peripheral wall, the suction port communicating between the outside and the motor accommodating chamber and for drawing the refrigerant as the fluid from the outside into the housing; An electric compressor in which only an annular seal member is provided between an inner circumferential surface of the seal peripheral wall and an outer circumferential surface of the housing peripheral wall, the case end wall and the housing end wall are in contact with each other at a position radially inward of the rotating shaft relative to a portion sealed by the seal member, When a portion of the outer circumferential surface of the housing peripheral wall that is surrounded by the seal peripheral wall is defined as a first housing outer circumferential surface, an axial length of the first housing outer circumferential surface is longer than an axial length of the inner circumferential surface of the seal peripheral wall, The first housing outer circumferential surface and the inner circumferential surface of the seal peripheral wall face each other with a certain gap therebetween, the seal member is a single member and has a first seal portion that seals between an inner peripheral surface of the seal peripheral wall and an outer peripheral surface of the first housing, and a second seal portion that extends from the first seal portion between the end face and the opposing surface in a radial direction of the rotation shaft and seals between the end face and the opposing surface, and a portion of the second seal portion extends from between the end face and the opposing surface to the outside of the housing, The electric compressor, wherein a recess is provided at a location where the first seal portion contacts the second seal portion.

2. The sealing member is provided integrally with an annular conductor, The electric compressor according to claim 1 , wherein the conductor is disposed between the end surface and the opposing surface.

3. 3. The electric compressor according to claim 2, wherein the conductor is sandwiched between the end surface and the opposing surface.

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