Electric compressor

Abstract

To provide an electric compressor which can connect an anode lead to a circuit board.SOLUTION: An axial direction of a plurality of electrolytic capacitors 63 extends in parallel with a direction perpendicular to an axial direction of a motor housing. The plurality of electrolytic capacitors 63 are arranged in a stacked state in the axial direction of the motor housing such that the plurality of electrolytic capacitors 63 are positioned in each stage. In each stage, the plurality of electrolytic capacitors 63 are aligned in a direction perpendicular to the axial direction of the electrolytic capacitor 63 with an interval therebetween. The interval between the electrolytic capacitors 63 in each stage expands sequentially from one side toward the other side in the axial direction of the motor housing. A second electrolytic capacitor 63b which is an electrolytic capacitor 63 positioned to the remotest stage from the circuit board 66 is arranged such that a distance from an anode base end part 69a of an anode lead 69 to the circuit board 66 is shorter than a distance from a cathode base end part 68a of a cathode lead 68 to the circuit board 66.SELECTED DRAWING: Figure 5

Description

Technical Field

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

Background Art

[0002] The electric compressor described in Patent Document 1 includes a compression part that compresses a fluid, an electric motor that drives the compression part, an inverter that drives the electric motor, and a metal housing. The housing has a cylindrical motor housing, an inverter housing, and a partition wall. The motor housing accommodates the electric motor and partitions an intake chamber into which the fluid is inhaled. The inverter housing partitions an inverter accommodation chamber that accommodates the inverter. The partition wall separates the intake chamber and the inverter accommodation chamber.

[0003] The inverter has a circuit board and a plurality of electrolytic capacitors. The circuit board is arranged such that the plate thickness direction coincides with the axial direction of the motor housing. Each of the plurality of electrolytic capacitors has a cylindrical capacitor body, a positive electrode lead and a negative electrode lead that extend from one end face in the axial direction of the capacitor body and are connected to the circuit board.

[0004] The axial directions of the plurality of electrolytic capacitors extend in parallel in a direction orthogonal to the axial direction of the motor housing. The plurality of electrolytic capacitors are arranged in a stacked state in the axial direction of the motor housing such that a plurality of electrolytic capacitors are positioned in each stage. In each stage, the plurality of electrolytic capacitors are arranged side by side with a space therebetween in a direction orthogonal to the axial direction of the electrolytic capacitor. The space between the electrolytic capacitors in each stage gradually widens from one side to the other side in the axial direction of the motor housing.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In order to make it easier to distinguish the polarity of the leads, generally, the negative electrode lead is set shorter than the positive electrode lead. For this reason, depending on the position of the electrolytic capacitor with respect to the circuit board, the positive electrode lead may be connectable to the circuit board, but the negative electrode lead may not be connectable to the circuit board. In particular, when a plurality of electrolytic capacitors are arranged in a stacked state as in Patent Document 1, the above problem is likely to occur in the electrolytic capacitor in the stage far from the circuit board.

Means for Solving the Problems

[0007] An electric compressor for solving the above problems includes a compression part that compresses a fluid, an electric motor that drives the compression part, an inverter that drives the electric motor, a cylindrical motor housing that houses the electric motor and partitions an intake chamber into which the fluid is inhaled, an inverter housing that partitions an inverter housing chamber that houses the inverter, and a metal housing having a partition wall that separates the intake chamber and the inverter housing chamber. The inverter includes a circuit board arranged such that the thickness direction thereof coincides with the axial direction of the motor housing, and a plurality of electrolytic capacitors. Each of the plurality of electrolytic capacitors has a cylindrical capacitor body, a positive electrode lead and a negative electrode lead that extend from one end surface in the axial direction of the capacitor body and are connected to the circuit board. The axial directions of the plurality of electrolytic capacitors extend in parallel in a direction intersecting the axial direction of the motor housing. The plurality of electrolytic capacitors are arranged in a stacked state in the axial direction of the motor housing such that a plurality of the electrolytic capacitors are positioned in each stage. In each stage, the plurality of electrolytic capacitors are arranged side by side with a space therebetween in a direction orthogonal to the axial direction of the electrolytic capacitor. The space between the electrolytic capacitors in each stage gradually widens from one side to the other side in the axial direction of the motor housing. Among the plurality of electrolytic capacitors, when the electrolytic capacitor in the stage closer to the circuit board is defined as a first electrolytic capacitor and the electrolytic capacitor in the stage farther from the circuit board is defined as a second electrolytic capacitor, the gist is that the second electrolytic capacitor is arranged such that the distance from the negative electrode base end portion of the negative electrode lead to the circuit board in the axial direction of the motor housing is shorter than the distance from the positive electrode base end portion of the positive electrode lead to the circuit board in the axial direction of the motor housing.

[0008] According to the above configuration, the second electrolytic capacitor is arranged such that the distance from the negative electrode base end portion to the circuit board is shorter than the distance from the positive electrode base end portion to the circuit board. Therefore, even if the negative electrode lead is shorter than the positive electrode lead, the negative electrode lead of the second electrolytic capacitor can be connected to the circuit board.

[0009] In the electric compressor, the inverter has a holder that is disposed between the partition wall and the circuit board in the axial direction of the motor housing and holds a plurality of the electrolytic capacitors. The plurality of electrolytic capacitors are disposed between the partition wall and the holder in the axial direction of the motor housing, and the intervals between the electrolytic capacitors in each stage may sequentially increase from the circuit board side toward the partition wall side in the axial direction of the motor housing.

[0010] According to the above configuration, the plurality of electrolytic capacitors are disposed between the partition wall and the circuit board in the axial direction of the motor housing. Therefore, compared with the case where the plurality of electrolytic capacitors are disposed on the side opposite to the partition wall with the circuit board sandwiched in the axial direction of the motor housing, the plurality of electrolytic capacitors can be disposed near the suction chamber. Thus, the cooling effect of the electrolytic capacitors is increased.

[0011] Also, according to the above configuration, the intervals between the electrolytic capacitors in each stage sequentially increase from the circuit board side toward the partition wall side in the axial direction of the motor housing. Therefore, compared with the case where the intervals between the electrolytic capacitors in each stage sequentially increase from the partition wall side toward the circuit board side in the axial direction of the motor housing, the contact area between the electrolytic capacitors and the holder can be increased. Thus, the holder can stably hold the plurality of electrolytic capacitors.

[0012] In the electric compressor, the housing may have a protruding portion that protrudes from the partition wall toward the plurality of electrolytic capacitors and is surrounded by the plurality of electrolytic capacitors.

[0013] According to the above configuration, the housing has a protruding portion that protrudes from the partition wall toward the plurality of electrolytic capacitors and is surrounded by the plurality of electrolytic capacitors. Thereby, compared with the case where the housing is not provided with the protruding portion, the distance between the housing and each electrolytic capacitor is shortened, and the area where the housing and each electrolytic capacitor face each other increases. Therefore, the heat of each electrolytic capacitor is more easily radiated to the housing, so that the cooling effect of the electrolytic capacitor is further increased.

[0014] In the above electric compressor, the inverter is disposed between the partition wall and the circuit board in the axial direction of the motor housing and has a holder for holding the plurality of electrolytic capacitors. The plurality of electrolytic capacitors are disposed between the partition wall and the holder in the axial direction of the motor housing. The holder has a positive electrode lead insertion hole through which the positive electrode lead of the second electrolytic capacitor is inserted and a negative electrode lead insertion hole through which the negative electrode lead of the second electrolytic capacitor is inserted. The distance between the positive electrode lead insertion hole and the negative electrode lead insertion hole may be shorter than the distance between the positive electrode base end portion and the negative electrode base end portion.

[0015] When the second electrolytic capacitor is arranged such that the distance from the negative electrode base end portion to the circuit board is shorter than the distance from the positive electrode base end portion to the circuit board, the distance between the portion of the positive electrode lead extending toward the circuit board and the portion of the negative electrode lead extending toward the circuit board is shorter than the distance between the positive electrode base end portion and the negative electrode base end portion.

[0016] According to the above configuration, the holder has a positive electrode lead insertion hole through which the positive electrode lead of the second electrolytic capacitor is inserted and a negative electrode lead insertion hole through which the negative electrode lead of the second electrolytic capacitor is inserted. The distance between the positive electrode lead insertion hole and the negative electrode lead insertion hole is shorter than the distance between the positive electrode base end portion and the negative electrode base end portion. Therefore, the holder can hold the second electrolytic capacitor arranged such that the distance from the negative electrode base end portion to the circuit board is shorter than the distance from the positive electrode base end portion to the circuit board.

[0017] In addition, since the holder is positioned between the circuit board and the electrolytic capacitor, the distance from the electrolytic capacitor to the circuit board is increased by the thickness of the holder. That is, the configuration in which the holder is positioned between the circuit board and the electrolytic capacitor is a configuration in which it is easy for the negative electrode lead not to reach the circuit board. Therefore, it is more effective to arrange the second electrolytic capacitor so that the distance from the negative electrode base end portion to the circuit board is shorter than the distance from the positive electrode base end portion to the circuit board.

[0018] In the above electric compressor, the circuit board has a first surface facing the holder and a second surface opposite to the first surface, and the positive electrode lead and the negative electrode lead may each penetrate the circuit board and be connected to the circuit board on the second surface of the circuit board.

[0019] For example, when connecting the positive electrode lead and the negative electrode lead to the circuit board on the first surface of the circuit board, the presence of the holder positioned between the circuit board and the electrolytic capacitor makes the connection work difficult. On the other hand, according to the above configuration, the positive electrode lead and the negative electrode lead are each connected to the circuit board on the second surface of the circuit board. Therefore, the connection work of the positive electrode lead and the negative electrode lead to the circuit board is easy.

[0020] On the other hand, when the positive electrode lead and the negative electrode lead are connected to the circuit board on the second surface of the circuit board, the lengths of the positive electrode lead and the negative electrode lead are additionally required by the thickness of the circuit board. For this reason, there is a possibility that the negative electrode lead may not reach the second surface of the circuit board. Therefore, it is more effective to arrange the second electrolytic capacitor so that the distance from the negative electrode base end portion to the circuit board is shorter than the distance from the positive electrode base end portion to the circuit board.

Effect of the Invention

[0021] According to the present invention, the negative electrode lead can be connected to the circuit board.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0023] Hereinafter, an embodiment in which an electric compressor is embodied will be described with reference to FIGS. 1 to 6. The electric compressor of the present embodiment is used, for example, in a vehicle air conditioner. <Configuration of Electric Compressor> As shown in FIG. 1, the electric compressor 10 includes a housing 11, a shaft support member 12, a rotating shaft 13, a compression unit 14, an electric motor 15, and an inverter 16. The housing 11 houses the shaft support member 12, the rotating shaft 13, the compression unit 14, the electric motor 15, and the inverter 16. The compression unit 14 compresses a refrigerant as a fluid. The electric motor 15 drives the compression unit 14 by rotating the rotating shaft 13. The inverter 16 drives the electric motor 15.

[0024] The housing 11 has a first component 21, a second component 22, and a third component 23. The first component 21, the second component 22, and the third component 23 are made of metal. Therefore, the housing 11 is made of metal. In the present embodiment, the first component 21, the second component 22, and the third component 23 are made of aluminum.

[0025] The first component 21 has a cylindrical motor housing 24 and a bottomed cylindrical inverter housing 25. The inverter housing 25 is continuous with the first end in the axial direction of the motor housing 24.

[0026] As shown in FIG. 2, the inverter housing 25 has a bottom wall 26 and a peripheral wall 27 extending in the thickness direction of the bottom wall 26 from the outer peripheral edge of the bottom wall 26. The thickness direction of the bottom wall 26 coincides with the axial direction of the motor housing 24. The outer shape of the bottom wall 26 is larger than the outer shape of the motor housing 24. The bottom wall 26 has a closing portion 28 and an extending portion 29.

[0027] As shown in FIG. 1, the closing portion 28 closes an opening located at the first end in the axial direction of the motor housing 24. The closing portion 28 has a first surface 28a and a second surface 28b. The first surface 28a constitutes a part of the inner surface of the bottom wall 26. The second surface 28b is the surface on the opposite side of the first surface 28a.

[0028] As shown in FIG. 2, the extending portion 29 is a portion located outside the outer peripheral surface 24a of the motor housing 24 in a direction orthogonal to the axial direction of the motor housing 24. The extending portion 29 has a first surface 29a and a second surface 29b. The first surface 29a constitutes a part of the inner surface of the bottom wall 26. The second surface 29b is the surface on the opposite side of the first surface 29a. The second surface 29b constitutes the outer surface of the bottom wall 26. The extending portion 29 is located on the opening side of the inverter housing 25 with respect to the closing portion 28. In other words, the closing portion 28 is recessed with respect to the extending portion 29.

[0029] As shown in FIG. 1, the inverter housing 25 has a boss 31. The boss 31 is a portion protruding in the axial direction of the motor housing 24 from the second surface 28b of the closing portion 28. The boss 31 has a bearing housing portion 31a. The bearing housing portion 31a is a portion recessed with respect to the tip surface of the boss 31. The bearing housing portion 31a houses the first bearing 17.

[0030] As shown in FIGS. 2 and 3, the inverter housing 25 of the present embodiment has a protruding portion 32. The protruding portion 32 is a portion that protrudes axially from the first surface 28a of the closing portion 28 toward the motor housing 24. The protruding portion 32 extends in a direction orthogonal to the axial direction of the motor housing 24. Hereinafter, the direction in which the protruding portion 32 extends is referred to as the extending direction of the protruding portion 32. The extending direction of the protruding portion 32 is a direction orthogonal to the axial direction of the motor housing 24. Further, a direction orthogonal to both the axial direction of the motor housing 24 and the extending direction of the protruding portion 32 is referred to as the width direction of the protruding portion 32. The dimension in the width direction of the protruding portion 32 increases from the tip end portion toward the base end portion. That is, the protruding portion 32 has a tapered shape that becomes wider from the opening side toward the bottom side of the inverter housing 25.

[0031] As shown in FIG. 1, the second component 22 is connected to the second end in the axial direction of the motor housing 24. The second end in the axial direction of the motor housing 24 is the end located opposite to the first end in the axial direction of the motor housing 24. The second component 22 closes an opening located at the second end in the axial direction of the motor housing 24.

[0032] The third component 23 is plate-shaped. The outer shape of the third component 23 is a shape corresponding to the peripheral wall 27 of the inverter housing 25 (see FIG. 4). The third component 23 is connected to the tip end portion of the peripheral wall 27 of the inverter housing 25. The third component 23 closes the opening of the inverter housing 25.

[0033] As shown in FIGS. 1 and 3, an inverter accommodation chamber S1 for accommodating the inverter 16 is defined by the inner surface of the bottom wall 26 of the inverter housing 25, the inner peripheral surface of the peripheral wall 27 of the inverter housing 25, and the inner surface 23a of the third component 23.

[0034] As shown in Fig. 1, the housing 11 has a suction port 11a and a discharge port 11b. The suction port 11a is provided in the motor housing 24. The suction port 11a is provided at a portion close to the inverter housing 25 in the axial direction of the motor housing 24. The discharge port 11b is provided in the second component 22. One end of an external refrigerant circuit (not shown) is connected to the suction port 11a, and the other end of the external refrigerant circuit is connected to the discharge port 11b.

[0035] The shaft support member 12 is housed in the motor housing 24. The shaft support member 12 has a shaft insertion hole 12a and a communication hole 12b. The second bearing 18 is housed in the shaft insertion hole 12a.

[0036] An intake chamber S2 into which refrigerant is inhaled is defined by the inner peripheral surface of the motor housing 24, the shaft support member 12, and the closing portion 28 of the inverter housing 25. The closing portion 28 separates the inverter housing chamber S1 from the intake chamber S2. Therefore, the housing 11 has the closing portion 28 as a partition wall that separates the inverter housing chamber S1 from the intake chamber S2.

[0037] The rotating shaft 13 is housed in the motor housing 24. The rotating shaft 13 extends along the axial direction of the motor housing 24. The first end portion of the rotating shaft 13 is inserted into the bearing housing portion 31a. The first end portion of the rotating shaft 13 is rotatably supported by the boss 31 via the first bearing 17. The second end portion located on the side opposite to the first end portion of the rotating shaft 13 is inserted through the shaft insertion hole 12a of the shaft support member 12. The second end portion of the rotating shaft 13 is rotatably supported by the shaft support member 12 via the second bearing 18.

[0038] The compression section 14 is housed within the motor housing 24. The compression section 14 is disposed between the shaft support member 12 and the second component 22 in the axial direction of the motor housing 24. The compression section 14 of the present embodiment is of the scroll type. The compression section 14 has a fixed scroll 14a and a movable scroll 14b. The fixed scroll 14a is fixed to the housing 11 by being sandwiched between the second component 22 and the shaft support member 12. The movable scroll 14b is disposed so as to face the fixed scroll 14a. A compression chamber S3 with a variable volume is defined between the fixed scroll 14a and the movable scroll 14b. The compression chamber S3 communicates with the suction chamber S2 via the communication hole 12b. A discharge chamber S4 is defined by the inner surface of the fixed scroll 14a and the second component 22. The compression chamber S3 and the discharge chamber S4 communicate with each other.

[0039] The electric motor 15 is housed within the suction chamber S2. That is, the suction chamber S2 is also a motor housing chamber that houses the electric motor 15. The electric motor 15 has a rotor 41 and a stator 42. The rotor 41 has a cylindrical rotor core 41a and a plurality of permanent magnets 41b. The rotor core 41a is fixed to the rotary shaft 13. The plurality of permanent magnets 41b are embedded in the rotor core 41a. The plurality of permanent magnets 41b are provided at equal pitches in the circumferential direction of the rotor core 41a. The stator 42 surrounds the rotor 41. The stator 42 has a cylindrical stator core 42a and a motor coil 42b. The stator core 42a is fixed to the inner circumferential surface of the motor housing 24. The motor coil 42b is wound around the stator core 42a. The rotor 41 rotates when an electric current flows through the motor coil 42b. The rotary shaft 13 rotates integrally with the rotor 41.

[0040] When the rotating shaft 13 rotates, the compression part 14 is driven. When the compression part 14 is driven, the refrigerant is inhaled into the suction chamber S2 from the outside refrigerant circuit through the suction port 11a. The refrigerant inhaled into the suction chamber S2 flows into the compression chamber S3 through the communication hole 12b. The refrigerant flowing into the compression chamber S3 is compressed by the volume change of the compression chamber S3. The compressed refrigerant is discharged into the discharge chamber S4. The refrigerant discharged into the discharge chamber S4 flows out from the discharge port 11b to the outside refrigerant circuit. The refrigerant flowing out to the outside refrigerant circuit refluxes into the suction chamber S2 from the suction port 11a through the heat exchanger and expansion valve of the outside refrigerant circuit. The electric compressor 10 and the outside refrigerant circuit constitute a vehicle air conditioner.

[0041] <Configuration of Inverter> As shown in FIG. 4, the inverter 16 has three-phase switching elements 61, a coil 62, a plurality of electrolytic capacitors 63, three-phase conductive members 64, a holder 65, and a circuit board 66. The inverter 16 of the present embodiment has four electrolytic capacitors 63 as the plurality of electrolytic capacitors 63.

[0042] The three-phase switching elements 61 perform a switching operation for driving the electric motor 15. The coil 62, together with the electrolytic capacitor 63, constitutes an LC circuit. The LC circuit is a filter circuit for reducing noise included in the input current from the outside. The three-phase switching elements 61, the coil 62, and the plurality of electrolytic capacitors 63 are electrically connected to the circuit board 66. The three-phase switching elements 61, the coil 62, and the electrolytic capacitor 63 generate heat during the operation of the inverter 16. The three-phase conductive member 64 electrically connects the electric motor 15 and the inverter 16. The holder 65 holds the three-phase switching elements 61, the coil 62, the plurality of electrolytic capacitors 63, and the three-phase conductive member 64. The holder 65 of the present embodiment is made of resin.

[0043] As shown in FIGS. 1 and 3, the inverter 16 is housed in the inverter housing chamber S1. The circuit board 66 is arranged such that the thickness direction thereof coincides with the axial direction of the motor housing 24. The circuit board 66 has a first surface 66a and a second surface 66b. The first surface 66a and the second surface 66b are surfaces orthogonal to the thickness direction of the circuit board 66. The second surface 66b is the surface on the opposite side of the first surface 66a. The first surface 66a is located on the side of the bottom wall 26. The second surface 66b is located on the side of the third component 23. The circuit board 66 has a portion aligned with the closing portion 28 and a portion aligned with the extending portion 29 in the axial direction of the motor housing 24.

[0044] <Configuration of the electrolytic capacitor> As shown in FIG. 2, the electrolytic capacitor 63 has a capacitor body 67, a positive electrode lead 68, and a negative electrode lead 69. The electrolytic capacitor 63 is electrically connected to the circuit board 66 when the positive electrode lead 68 and the negative electrode lead 69 are connected to the circuit board 66.

[0045] The capacitor body 67 is cylindrical. The axial dimension of the capacitor body 67 is larger than the outer diameter of the capacitor body 67. Therefore, the axial direction of the capacitor body 67 is also the longitudinal direction of the capacitor body 67. The capacitor body 67 has a first end face 67a and a second end face 67b. The first end face 67a is one end face in the axial direction of the capacitor body 67, and the second end face 67b is the other end face in the axial direction of the capacitor body 67. The second end face 67b is a conductive surface. A pressure valve (not shown) is provided on the second end face 67b.

[0046] The positive electrode lead 68 and the negative electrode lead 69 each extend from the first end face 67a of the capacitor body 67. To make it easier to distinguish the polarities of the leads, the negative electrode lead 69 is set shorter than the positive electrode lead 68. The positive electrode lead 68 has a positive electrode base end portion 68a. The positive electrode base end portion 68a is the end portion of the positive electrode lead 68 located on the first end face 67a of the capacitor body 67. The negative electrode lead 69 has a negative electrode base end portion 69a. The negative electrode base end portion 69a is the end portion of the negative electrode lead 69 located on the first end face 67a of the capacitor body 67.

[0047] <Configuration of the Holder> As shown in FIGS. 3 and 4, the holder 65 has a flat base plate 71. The base plate 71 of the present embodiment is disc-shaped. The holder 65 is disposed between the closing portion 28 and the circuit board 66 in the axial direction of the motor housing 24. Therefore, the three-phase switching element 61, the coil 62, the plurality of electrolytic capacitors 63, and the three-phase conductive member 64 held by the holder 65 are disposed between the closing portion 28 and the circuit board 66 in the axial direction of the motor housing 24. The thickness direction of the base plate 71 coincides with the thickness direction of the circuit board 66 and the axial direction of the motor housing 24. The holder 65 and the circuit board 66 are fixed to the first component 21 of the housing 11 by bolts B.

[0048] Let the region obtained by projecting the outer peripheral surface 24a of the motor housing 24 in the axial direction of the motor housing 24 be the projection region. Since the motor housing 24 of the present embodiment is cylindrical, the projection region is circular. The holder 65 is located within the projection region. Therefore, the three-phase switching element 61, the coil 62, the plurality of electrolytic capacitors 63, and the three-phase conductive member 64 held by the holder 65 are located within the projection region. The three-phase switching element 61, the coil 62, the plurality of electrolytic capacitors 63, and the three-phase conductive member 64 are arranged side by side with the suction chamber S2 in the axial direction of the motor housing 24.

[0049] The base plate 71 has a first surface 71a and a second surface 71b. The first surface 71a and the second surface 71b are surfaces orthogonal to the thickness direction of the base plate 71. The second surface 71b is the surface on the opposite side of the first surface 71a. The first surface 71a faces the first surface 28a of the closing portion 28. That is, the first surface 71a is the surface on the partition wall side in the holder 65. The second surface 71b faces the first surface 66a of the circuit board 66.

[0050] The holder 65 has a capacitor holding portion 72 that holds a plurality of electrolytic capacitors 63. The capacitor holding portion 72 is provided on the first surface 71a of the base plate 71. Therefore, the plurality of electrolytic capacitors 63 are held on the surface of the holder 65 on the side of the closing portion 28. The plurality of electrolytic capacitors 63 are arranged between the closing portion 28 and the holder 65 in the axial direction of the motor housing 24. The capacitor holding portion 72 protrudes from the first surface 71a of the base plate 71 toward the closing portion 28. The capacitor holding portion 72 of the present embodiment is substantially rectangular. The longitudinal direction of the capacitor holding portion 72 coincides with the extending direction of the protruding portion 32. The short side direction of the capacitor holding portion 72 coincides with the width direction of the protruding portion 32.

[0051] The capacitor holding portion 72 has a capacitor housing recess 73 in which a plurality of electrolytic capacitors 63 are housed. The capacitor housing recess 73 is recessed with respect to the tip surface of the capacitor holding portion 72. The capacitor housing recess 73 is defined by two first curved surfaces 73a and two second curved surfaces 73b.

[0052] The two first curved surfaces 73a are located on the bottom side of the capacitor housing recess 73. The two first curved surfaces 73a are arranged in the short side direction of the capacitor holding portion 72. The two first curved surfaces 73a extend parallel to each other in the longitudinal direction of the capacitor holding portion 72. Each first curved surface 73a is a curved surface that follows the outer peripheral surface of the capacitor body 67.

[0053] The two second curved surfaces 73b are located on the opening side of the capacitor housing recess 73. The two second curved surfaces 73b are positioned so as to sandwich the two first curved surfaces 73a in the short direction of the capacitor holding portion 72. The two second curved surfaces 73b extend in parallel in the longitudinal direction of the capacitor holding portion 72. Each second curved surface 73b is a curved surface along the outer peripheral surface of the capacitor body 67.

[0054] As shown in FIG. 4, the capacitor holding portion 72 has a plate-shaped cover portion 74. The cover portion 74 is located at the first end in the longitudinal direction of the capacitor holding portion 72. As shown in FIGS. 5 and 6, the holder 65 is provided with a positive electrode lead insertion hole 75 through which the positive electrode lead 68 is inserted and a negative electrode lead insertion hole 76 through which the negative electrode lead 69 is inserted. The number of the positive electrode lead insertion holes 75 and the number of the negative electrode lead insertion holes 76 are each the same as the number of the electrolytic capacitors 63. Therefore, the holder 65 of the present embodiment is provided with four positive electrode lead insertion holes 75 and four negative electrode lead insertion holes 76.

[0055] The four positive electrode lead insertion holes 75 and the four negative electrode lead insertion holes 76 are located at the second end in the longitudinal direction of the capacitor holding portion 72. That is, the four positive electrode lead insertion holes 75 and the four negative electrode lead insertion holes 76 are located on the side opposite to the cover portion 74 in the longitudinal direction of the capacitor holding portion 72. The positive electrode lead insertion hole 75 is aligned with the first curved surface 73a or the second curved surface 73b in the longitudinal direction of the capacitor holding portion 72. The negative electrode lead insertion hole 76 is aligned with the first curved surface 73a or the second curved surface 73b in the longitudinal direction of the capacitor holding portion 72.

[0056] The pair of positive electrode lead insertion holes 75 and negative electrode lead insertion holes 76 provided for one electrolytic capacitor 63 are arranged at intervals in the short direction of the capacitor holding portion 72. The distance between the positive electrode lead insertion hole 75 and the negative electrode lead insertion hole 76 provided for one electrolytic capacitor 63 is shorter than the distance between the positive electrode base end portion 68a and the negative electrode base end portion 69a.

[0057] <Arrangement of electrolytic capacitors> As shown in FIG. 3, a plurality of electrolytic capacitors 63 are held by a capacitor holding portion 72. The plurality of electrolytic capacitors 63 are housed in a capacitor housing recess 73. Each electrolytic capacitor 63 is arranged such that the outer peripheral surface of the capacitor body 67 is along the first curved surface 73a or the second curved surface 73b. The capacitor body 67 of each electrolytic capacitor 63 is fixed to the first curved surface 73a or the second curved surface 73b by an adhesive (not shown).

[0058] As shown in FIGS. 5 and 6, the axial direction of each electrolytic capacitor 63 coincides with the direction in which the first curved surface 73a and the second curved surface 73b extend, that is, the longitudinal direction of the capacitor holding portion 72. The first end surface 67a of the capacitor body 67 is located on the side of the positive electrode lead insertion hole 75 and the negative electrode lead insertion hole 76. The second end surface 67b of the capacitor body 67 is located on the side of the cover portion 74. In the electrolytic capacitor 63 arranged along the first curved surface 73a, the entire second end surface 67b of the capacitor body 67 is covered by the cover portion 74. In the electrolytic capacitor 63 arranged along the second curved surface 73b, a part of the second end surface 67b of the capacitor body 67 is covered by the cover portion 74.

[0059] As shown in FIG. 3, the axial directions of the plurality of electrolytic capacitors 63 extend in parallel in a direction orthogonal to the axial direction of the motor housing 24. In the present embodiment, the axial directions of the four electrolytic capacitors 63 extend in parallel in the extending direction of the protruding portion 32.

[0060] The plurality of electrolytic capacitors 63 are arranged in a stacked state in the axial direction of the motor housing 24. In the present embodiment, the four electrolytic capacitors 63 are stacked in two stages in the axial direction of the motor housing 24. A plurality of electrolytic capacitors 63 are located in each stage. In the present embodiment, two electrolytic capacitors 63 are located in each stage. The two electrolytic capacitors 63 arranged along the first curved surface 73a are arranged in the stage closer to the circuit board 66. The two electrolytic capacitors 63 arranged along the second curved surface 73b are arranged in the stage farther from the circuit board 66.

[0061] In the following description, among the four electrolytic capacitors 63, the electrolytic capacitor 63 in the stage closer to the circuit board 66 is referred to as the first electrolytic capacitor 63a, and the electrolytic capacitor 63 in the stage farther from the circuit board 66 is referred to as the second electrolytic capacitor 63b.

[0062] In each stage, the plurality of electrolytic capacitors 63 are arranged side by side with a space therebetween in a direction orthogonal to the axial direction of the electrolytic capacitor 63. In the present embodiment, in the stage closer to the circuit board 66, the two first electrolytic capacitors 63a are arranged side by side with a space therebetween in a direction orthogonal to the axial direction of the electrolytic capacitor 63, specifically, in the width direction of the protruding portion 32. In the stage farther from the circuit board 66, the two second electrolytic capacitors 63b are arranged side by side with a space therebetween in a direction orthogonal to the axial direction of the electrolytic capacitor 63, specifically, in the width direction of the protruding portion 32.

[0063] The intervals between the electrolytic capacitors 63 in each stage gradually widen from one side to the other side in the axial direction of the motor housing 24. In the present embodiment, the interval between the two second electrolytic capacitors 63b in the stage farther from the circuit board 66 is wider than the interval between the two first electrolytic capacitors 63a in the stage closer to the circuit board 66. That is, the intervals between the electrolytic capacitors 63 in each stage gradually widen from the circuit board 66 side toward the closing portion 28 side in the axial direction of the motor housing 24.

[0064] In this embodiment, one end of the capacitor body 67 of the first electrolytic capacitor 63a in the axial direction of the motor housing 24 and one end of the capacitor body 67 of the second electrolytic capacitor 63b in the axial direction of the motor housing 24 overlap in the width direction of the protruding portion 32. Also, one end of the capacitor body 67 of the first electrolytic capacitor 63a in the width direction of the protruding portion 32 and one end of the capacitor body 67 of the second electrolytic capacitor 63b in the width direction of the protruding portion 32 overlap in the axial direction of the motor housing 24.

[0065] As shown in FIG. 6, the first electrolytic capacitor 63a and the second electrolytic capacitor 63b are arranged in a state shifted in the axial direction of the electrolytic capacitor 63. The first end face 67a of the capacitor body 67 of the second electrolytic capacitor 63b protrudes in the axial direction of the electrolytic capacitor 63 more than the first end face 67a of the capacitor body 67 of the first electrolytic capacitor 63a. The second end face 67b of the capacitor body 67 of the first electrolytic capacitor 63a protrudes in the axial direction of the electrolytic capacitor 63 more than the second end face 67b of the capacitor body 67 of the second electrolytic capacitor 63b.

[0066] As shown in FIG. 1, in this embodiment, the electrolytic capacitor 63 is arranged such that the distance from the suction port 11a to the first end face 67a of the capacitor body 67 is shorter than the distance from the suction port 11a to the second end face 67b of the capacitor body 67. The positive electrode lead 68 and the negative electrode lead 69 are located between the capacitor body 67 and the suction port 11a in a direction orthogonal to the axial direction of the motor housing 24.

[0067] As shown in FIGS. 5 and 6, each first electrolytic capacitor 63a is arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 in the axial direction of the motor housing 24 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66 in the axial direction of the motor housing 24. Each second electrolytic capacitor 63b is arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 in the axial direction of the motor housing 24 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66 in the axial direction of the motor housing 24. The virtual straight line L connecting the positive electrode base end portion 68a and the negative electrode base end portion 69a is inclined with respect to the first surface 66a and the second surface 66b of the circuit board 66. In the present embodiment, the virtual straight line L is inclined at about 45 degrees with respect to the first surface 66a and the second surface 66b of the circuit board 66.

[0068] Most of the positive electrode lead 68 of each electrolytic capacitor 63, except for a part on the positive electrode base end portion 68a side, is bent so as to extend perpendicular to the axial direction of the capacitor body 67. The bent portion of the positive electrode lead 68 extends toward the base plate 71 and the circuit board 66. The positive electrode lead 68 is inserted into the positive electrode lead insertion hole 75. Specifically, the positive electrode lead 68 of the first electrolytic capacitor 63a is inserted into the positive electrode lead insertion hole 75 provided so as to be aligned with the first curved surface 73a. The positive electrode lead 68 of the second electrolytic capacitor 63b is inserted into the positive electrode lead insertion hole 75 provided so as to be aligned with the second curved surface 73b. The positive electrode lead 68 penetrates the base plate 71 in the plate thickness direction.

[0069] For each electrolytic capacitor 63, the negative electrode lead 69 is bent such that most of it, except for a part on the side of the negative electrode base end portion 69a, extends perpendicular to the axial direction of the capacitor body 67. The bent portion of the negative electrode lead 69 extends toward the base plate 71 and the circuit board 66. The negative electrode lead 69 is inserted through the negative electrode lead insertion hole 76. Specifically, the negative electrode lead 69 of the first electrolytic capacitor 63a is inserted through the negative electrode lead insertion hole 76 provided so as to be aligned with the first curved surface 73a. The negative electrode lead 69 of the second electrolytic capacitor 63b is inserted through the negative electrode lead insertion hole 76 provided so as to be aligned with the second curved surface 73b. The negative electrode lead 69 penetrates the base plate 71 in the plate thickness direction.

[0070] In this embodiment, the positive electrode lead 68 and the negative electrode lead 69 are each drawn out to the second surface 66b side of the circuit board 66 by penetrating the circuit board 66 in the plate thickness direction. The positive electrode lead 68 and the negative electrode lead 69 are each connected to the circuit board 66 on the second surface 66b of the circuit board 66. Specifically, the portions of the positive electrode lead 68 and the negative electrode lead 69 protruding from the second surface 66b of the circuit board 66 are each soldered to the second surface 66b of the circuit board 66. Thereby, the electrolytic capacitor 63 is electrically connected to the circuit board 66.

[0071] In addition, when the protruding amount of the positive electrode lead 68 from the second surface 66b of the circuit board 66 is large, the tip of the positive electrode lead 68 may be cut within the range where the connection operation of the positive electrode lead 68 to the second surface 66b of the circuit board 66 is possible. Similarly, when the protruding amount of the negative electrode lead 69 from the second surface 66b of the circuit board 66 is large, the tip of the negative electrode lead 69 may be cut within the range where the connection operation of the negative electrode lead 69 to the second surface 66b of the circuit board 66 is possible. For example, at least one of the positive electrode lead 68 and the negative electrode lead 69 is cut so that the protruding amount of the positive electrode lead 68 from the second surface 66b of the circuit board 66 and the protruding amount of the negative electrode lead 69 from the second surface 66b of the circuit board 66 become the same.

[0072] As shown in FIG. 3, the protruding portion 32 protrudes from the closing portion 28 toward the plurality of electrolytic capacitors 63. The protruding portion 32 is located between the two second electrolytic capacitors 63b. The protruding portion 32 is surrounded by the four electrolytic capacitors 63. A heat dissipation grease 19 as a heat dissipation member is provided between the outer peripheral surface of the capacitor body 67 of each electrolytic capacitor 63 and the protruding portion 32. The heat dissipation grease 19 is in contact with each of the capacitor body 67 and the protruding portion 32.

[0073] The heat of each electrolytic capacitor 63 is transmitted to the closing portion 28 through the heat dissipation grease 19 and the protruding portion 32. The closing portion 28 is cooled by the refrigerant sucked into the suction chamber S2. That is, each electrolytic capacitor 63 is cooled by the refrigerant sucked into the suction chamber S2 through the heat dissipation grease 19, the protruding portion 32, and the closing portion 28.

[0074] As shown in FIG. 4, the three-phase switching elements 61, the coils 62, and the three-phase conductive members 64 are held on the first surface 71a of the base plate 71. The three-phase switching elements 61, the coils 62, and the three-phase conductive members 64 are arranged between the closing portion 28 and the holder 65 in the axial direction of the motor housing 24. The three-phase switching elements 61 and the plurality of electrolytic capacitors 63 are arranged side by side in the axial direction of the electrolytic capacitors 63. In the present embodiment, the electrolytic capacitors 63 are arranged such that the distance from the first end surface 67a of the capacitor body 67 to the switching element 61 is shorter than the distance from the second end surface 67b of the capacitor body 67 to the switching element 61. The positive electrode lead 68 and the negative electrode lead 69 are located between the capacitor body 67 and the three-phase switching element 61 in the axial direction of the electrolytic capacitor 63. The three-phase switching elements 61 and the plurality of electrolytic capacitors 63 are arranged between the coil 62 and the three-phase conductive members 64 in a direction orthogonal to the axial direction of the electrolytic capacitors 63.

[0075] As shown in FIG. 1, an insulating member 80 is disposed between the switching element 61 and the closing portion 28. The heat of the switching element 61 is transmitted to the closing portion 28 through the insulating member 80. The closing portion 28 is cooled by the refrigerant sucked into the suction chamber S2. That is, the switching element 61 is cooled by the refrigerant sucked into the suction chamber S2 through the insulating member 80 and the closing portion 28. The coil 62 is disposed in contact with the closing portion 28. The heat of the coil 62 is transmitted to the closing portion 28. The closing portion 28 is cooled by the refrigerant sucked into the suction chamber S2. That is, the switching element 61 is cooled by the refrigerant sucked into the suction chamber S2 through the closing portion 28.

[0076] [Operation of the Present Embodiment] The operation of the present embodiment will be described. Each of the plurality of electrolytic capacitors 63 has a columnar capacitor body 67, a positive electrode lead 68 that extends from the first end face 67a of the capacitor body 67 and is electrically connected to the circuit board 66, and a negative electrode lead 69. The axial directions of the plurality of electrolytic capacitors 63 extend in parallel in a direction orthogonal to the axial direction of the motor housing 24. The plurality of electrolytic capacitors 63 are arranged in a stacked state in the axial direction of the motor housing 24 such that a plurality of electrolytic capacitors 63 are located at each stage. At each stage, the plurality of electrolytic capacitors 63 are arranged side by side with a space therebetween in a direction orthogonal to the axial direction of the electrolytic capacitor 63. The intervals between the electrolytic capacitors 63 at each stage gradually widen from one side to the other side in the axial direction of the motor housing 24.

[0077] Since the plurality of electrolytic capacitors 63 are arranged in a stacked state in this way, all the electrolytic capacitors 63 are arranged in a row so that the axial direction of each electrolytic capacitor 63 is orthogonal to the axial direction of the motor housing 24. Compared with this case, the area of the plurality of electrolytic capacitors 63 when viewed from the axial direction of the motor housing 24 decreases. Therefore, the switching element 61 and the coil 62, which are heat generating elements other than the electrolytic capacitor 63, can be arranged in the inverter housing chamber S1 so as to easily exchange heat with the suction chamber S2. As a result, the cooling effect of the switching element 61 and the coil 62 can be increased.

[0078] On the other hand, when the plurality of electrolytic capacitors 63 are arranged in a stacked state, the distance from the second electrolytic capacitor 63b located at a stage far from the circuit board 66 to the circuit board 66 becomes larger compared with the case where all the electrolytic capacitors 63 are arranged in a row. Also, generally, in order to easily distinguish the polarity of the leads, the negative electrode lead 69 is set shorter than the positive electrode lead 68.

[0079] For this reason, for example, if the second electrolytic capacitor 63b is arranged so that the distance from the positive electrode base end portion 68a to the circuit board 66 in the axial direction of the motor housing 24 is the same as the distance from the negative electrode base end portion 69a to the circuit board 66 in the axial direction of the motor housing 24, the length of the negative electrode lead 69 may be insufficient, and the negative electrode lead 69 of the second electrolytic capacitor 63b may not be connected to the circuit board 66. On the other hand, in the present embodiment, the second electrolytic capacitor 63b is arranged so that the distance from the negative electrode base end portion 69a to the circuit board 66 in the axial direction of the motor housing 24 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66 in the axial direction of the motor housing 24. Thereby, the negative electrode lead 69 of the second electrolytic capacitor 63b can be connected to the circuit board 66.

[0080] [Effects of the present embodiment] The effects of the present embodiment will be described. (1) The second electrolytic capacitor 63b is arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 in the axial direction of the motor housing 24 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66 in the axial direction of the motor housing 24. Thereby, even if the negative electrode lead 69 is shorter than the positive electrode lead 68, the negative electrode lead 69 of the second electrolytic capacitor 63b can be connected to the circuit board 66.

[0081] (2) The inverter 16 has a holder 65 that is arranged between the closing portion 28 and the circuit board 66 in the axial direction of the motor housing 24 and holds a plurality of electrolytic capacitors 63. The plurality of electrolytic capacitors 63 are arranged between the closing portion 28 and the holder 65 in the axial direction of the motor housing 24. Therefore, the plurality of electrolytic capacitors 63 can be arranged closer to the suction chamber S2 as compared with the case where the plurality of electrolytic capacitors 63 are arranged on the side opposite to the closing portion 28 with the circuit board 66 sandwiched therebetween in the axial direction of the motor housing 24. Accordingly, the cooling effect of the electrolytic capacitor 63 is increased.

[0082] Also, the intervals between the electrolytic capacitors 63 at each stage are sequentially widened from the circuit board 66 side toward the closing portion 28 side in the axial direction of the motor housing 24. Therefore, the contact area between the electrolytic capacitor 63 and the holder 65 can be made larger as compared with the case where the intervals between the electrolytic capacitors 63 at each stage are sequentially widened from the closing portion 28 side toward the circuit board 66 side in the axial direction of the motor housing 24. Accordingly, in the present embodiment, the holder 65 can stably hold the plurality of electrolytic capacitors 63.

[0083] Note that, in order to stably hold the electrolytic capacitor 63, the holder 65 may be provided with a portion for holding the electrolytic capacitor 63 from the side of the closing portion 28. However, when the portion for holding the electrolytic capacitor 63 from the side of the closing portion 28 is provided in the holder 65, for example, the following three demerits occur. The first demerit is that the structure of the holder 65 becomes complicated. The second demerit is that it becomes difficult to attach the electrolytic capacitor 63 to the holder 65. The third demerit is that since the holder 65 is interposed between the electrolytic capacitor 63 and the closing portion 28, the area where the electrolytic capacitor 63 and the protruding portion 32 face each other decreases. On the other hand, the holder 65 of the present embodiment can stably hold a plurality of electrolytic capacitors 63 even without a portion for holding the electrolytic capacitor 63 from the side of the closing portion 28, so that the above three demerits can be avoided.

[0084] (3) The housing 11 has a protruding portion 32 that protrudes from the closing portion 28 toward the plurality of electrolytic capacitors 63 and is surrounded by the plurality of electrolytic capacitors 63. As a result, compared with the case where the housing 11 is not provided with the protruding portion 32, the distance between the housing 11 and each electrolytic capacitor 63 is shortened, and the area where the housing 11 and each electrolytic capacitor 63 face each other increases. Therefore, the heat of each electrolytic capacitor 63 is more easily dissipated to the housing 11, so that the cooling effect of the electrolytic capacitor 63 is further increased.

[0085] (4) For example, when the intervals between the electrolytic capacitors 63 of each stage gradually increase from the side of the closing portion 28 toward the circuit board 66 in the axial direction of the motor housing 24, the following problems occur. Similar to this embodiment, in order to increase the cooling effect of the electrolytic capacitor 63, it is conceivable to project the projecting portion 32 from the first surface 28a of the closing portion 28. However, in the case of the above example, since the distance from the projecting portion 32 to the circuit board 66 becomes smaller than that in this embodiment, it may be difficult to ensure insulation between the housing 11 and the circuit board 66. For example, if the circuit board 66 is arranged away from the projecting portion 32, although insulation between the housing 11 and the circuit board 66 can be ensured, the electric compressor 10 becomes larger in size.

[0086] In contrast, in this embodiment, the intervals between the electrolytic capacitors 63 of each stage gradually increase from the side of the circuit board 66 toward the closing portion 28 in the axial direction of the motor housing 24. In this case, since the distance from the projecting portion 32 to the circuit board 66 becomes larger than that in the above example, it is easy to ensure insulation between the housing 11 and the circuit board 66. Also, an increase in the size of the electric compressor 10 caused by ensuring insulation between the housing 11 and the circuit board 66 can be avoided.

[0087] (5) When the second electrolytic capacitor 63b is arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66, the distance between the portion of the positive electrode lead 68 extending toward the circuit board 66 and the portion of the negative electrode lead 69 extending toward the circuit board 66 is shorter than the distance between the positive electrode base end portion 68a and the negative electrode base end portion 69a.

[0088] The holder 65 of this embodiment has a positive electrode lead insertion hole 75 through which the positive electrode lead 68 of the second electrolytic capacitor 63b is inserted, and a negative electrode lead insertion hole 76 through which the negative electrode lead 69 of the second electrolytic capacitor 63b is inserted. The distance between the positive electrode lead insertion hole 75 and the negative electrode lead insertion hole 76 is shorter than the distance between the positive electrode base end portion 68a and the negative electrode base end portion 69a. Therefore, the holder 65 can hold the second electrolytic capacitor 63b arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66.

[0089] Also, since the holder 65 of this embodiment is located between the circuit board 66 and the electrolytic capacitor 63, the distance from the electrolytic capacitor 63 to the circuit board 66 becomes larger by the thickness of the holder 65. That is, the configuration in which the holder 65 is located between the circuit board 66 and the electrolytic capacitor 63 is a configuration in which the negative electrode lead 69 is likely not to reach the circuit board 66. Therefore, it is more effective to arrange the second electrolytic capacitor 63b such that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66.

[0090] (6) The circuit board 66 has a first surface 66a facing the holder 65 and a second surface 66b which is the surface on the side opposite to the first surface 66a. For example, when the positive electrode lead 68 and the negative electrode lead 69 are electrically connected to the circuit board 66 on the first surface 66a of the circuit board 66, the connection work is difficult due to the presence of the holder 65 located between the circuit board 66 and the electrolytic capacitor 63. In contrast, in this embodiment, the positive electrode lead 68 and the negative electrode lead 69 each penetrate the circuit board 66 and are connected to the circuit board 66 on the second surface 66b. Therefore, the connection work of the positive electrode lead 68 and the negative electrode lead 69 to the circuit board 66 is easy.

[0091] On the other hand, when the positive electrode lead 68 and the negative electrode lead 69 are connected to the circuit board 66 on the second surface 66b of the circuit board 66, the lengths of the positive electrode lead 68 and the negative electrode lead 69 become unnecessarily long by the thickness of the circuit board 66. For this reason, there is a possibility that the negative electrode lead 69 may not reach the second surface 66b of the circuit board 66. Therefore, it is more effective to arrange the second electrolytic capacitor 63b so that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66.

[0092] (7) The axial directions of the plurality of electrolytic capacitors 63 extend in parallel in a direction orthogonal to the axial direction of the motor housing 24. The plurality of electrolytic capacitors 63 are arranged in a stacked state in the axial direction of the motor housing 24 such that a plurality of electrolytic capacitors 63 are positioned at each stage. For this reason, compared with the case where all the electrolytic capacitors 63 are arranged in a line, the area of the plurality of electrolytic capacitors 63 when viewed from the axial direction of the motor housing 24 is reduced. Therefore, the switching element 61 and the coil 62 can be arranged in the inverter housing chamber S1 so as to easily exchange heat with the suction chamber S2. As a result, the cooling effect of the switching element 61 and the coil 62 can be increased.

[0093] (8) A part of the first electrolytic capacitor 63a and a part of the second electrolytic capacitor 63b overlap in the width direction of the protruding portion 32. Thereby, the plurality of electrolytic capacitors 63 can be miniaturized in the axial direction of the motor housing 24 as compared with the case where a part of the first electrolytic capacitor 63a and a part of the second electrolytic capacitor 63b do not overlap in the width direction of the protruding portion 32.

[0094] (9) A part of the first electrolytic capacitor 63a and a part of the second electrolytic capacitor 63b overlap in the axial direction of the motor housing 24. Thereby, the plurality of electrolytic capacitors 63 can be miniaturized in the width direction of the protruding portion 32 as compared with the case where a part of the first electrolytic capacitor 63a and a part of the second electrolytic capacitor 63b do not overlap in the axial direction of the motor housing 24.

[0095] (10) The electrolytic capacitor 63 is arranged such that the distance from the suction port 11a to the first end face 67a of the capacitor body 67 is shorter than the distance from the suction port 11a to the second end face 67b of the capacitor body 67. Thereby, the positive electrode lead 68 and the negative electrode lead 69 can be arranged closer to the suction port 11a. Therefore, it is easy to cool the positive electrode lead 68 and the negative electrode lead 69.

[0096] (11) The electrolytic capacitor 63 is arranged such that the distance from the first end face 67a of the capacitor body 67 to the switching element 61 is shorter than the distance from the second end face 67b of the capacitor body 67 to the switching element 61. Thereby, the distances between the positive electrode lead 68 and the negative electrode lead 69 and the switching element 61 can be shortened. Therefore, the impedance between the electrolytic capacitor 63 and the switching element 61 can be reduced.

[0097] (12) The second end face 67b of the electrolytic capacitor 63 is a conductive surface. The holder 65 has a cover portion 74 that covers the second end face 67b of the electrolytic capacitor 63. For this reason, the cover portion 74 can insulate the second end face 67b of the electrolytic capacitor 63 from the circuit board 66.

[0098] [Modification Example] Note that the above embodiment can be modified as follows. The above embodiment and the following modification examples can be implemented in combination with each other within a technically non - conflicting range.

[0099] ○ The configuration of the housing 11 may be appropriately changed. For example, the motor housing 24 and the inverter housing 25 may be separate. In this case, the motor housing 24 may have a cylindrical wall and an end wall that closes an opening located at one axial end of the cylindrical wall. The suction chamber S2 may be defined by the cylindrical wall and the end wall of the motor housing 24, and the shaft support member 12. The inverter housing 25 is arranged such that the closing portion 28 abuts against the end wall of the motor housing 24. In this case, the partition wall is constituted by the end wall of the motor housing 24 and the closing portion 28 of the inverter housing 25.

[0100] Note that in the above example, the inverter housing 25 may not have the closing portion 28. In this case, the inverter accommodation chamber S1 is defined by the end wall of the motor housing 24, the peripheral wall 27 and the extending portion 29 of the inverter housing 25, and the third component 23. The partition wall is constituted by the end wall of the motor housing 24.

[0101] For example, the first surface 28a of the closing portion 28 and the first surface 29a of the extending portion 29 may be flush. For example, the peripheral wall 27 of the inverter housing 25 may be cylindrical with an outer diameter the same as that of the motor housing 24. In this case, the bottom wall 26 does not have the extending portion 29. The entire bottom wall 26 of the inverter housing 25 serves as the closing portion 28.

[0102] ○ In the above embodiment, the plurality of electrolytic capacitors 63 were stacked in two stages in the axial direction of the motor housing 24, but they may be stacked in three or more stages. For example, when the plurality of electrolytic capacitors 63 are stacked in three stages in the axial direction of the motor housing 24, the first stage, the second stage, and the third stage are defined from the circuit board 66 side toward the closing portion 28 side. At this time, the stage close to the circuit board is the first stage. The stages far from the circuit board are the second stage and the third stage. Therefore, the electrolytic capacitor 63 of the first stage is the first electrolytic capacitor. The electrolytic capacitors 63 of the second stage and the third stage are the second electrolytic capacitors.

[0103] ○ It is only necessary that at least the second electrolytic capacitor 63b is arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66. That is, the first electrolytic capacitor 63a does not necessarily have to be arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66. The first electrolytic capacitor 63a may be arranged, for example, such that the distance from the negative electrode base end portion 69a to the circuit board 66 is the same as the distance from the positive electrode base end portion 68a to the circuit board 66.

[0104] ○ The inclination angle of the virtual straight line L with respect to the first surface 66a and the second surface 66b of the circuit board 66 may be appropriately changed. The larger the inclination angle, the easier it is for the negative electrode lead 69 to reach the circuit board 66. On the other hand, the larger the inclination angle, the closer the distance between the portion of the positive electrode lead 68 extending toward the circuit board 66 and the portion of the negative electrode lead 69 extending toward the circuit board 66 becomes. For this reason, the inclination angle is set to an angle such that each of the positive electrode lead 68 and the negative electrode lead 69 can be connected to the circuit board 66 and an insulation distance between the positive electrode lead 68 and the negative electrode lead 69 is ensured.

[0105] ○ When a plurality of electrolytic capacitors 63 are arranged between the closing portion 28 and the circuit board 66 in the axial direction of the motor housing 24, the intervals between the electrolytic capacitors 63 at each stage may sequentially widen from the closing portion 28 side toward the circuit board 66 side in the axial direction of the motor housing 24.

[0106] ○ In the above embodiment, the axial directions of the plurality of electrolytic capacitors 63 extended in parallel in a direction orthogonal to the axial direction of the motor housing 24, but it is not limited to this. The axial directions of the plurality of electrolytic capacitors 63 only need to extend in parallel in a direction intersecting the axial direction of the motor housing 24. Even in this case, the same effect as the effect (7) of the above embodiment can be obtained.

[0107] ○ The plurality of electrolytic capacitors 63 may be arranged between the inner surface 23a of the third component 23 and the circuit board 66 in the axial direction of the motor housing 24. In this case, the intervals between the electrolytic capacitors 63 in each stage may sequentially widen from the third component 23 side toward the circuit board 66 side in the axial direction of the motor housing 24, or may sequentially widen from the circuit board 66 side toward the third component 23 side. Further, the protruding portion 32 may protrude from the inner surface 23a of the third component 23 toward the plurality of electrolytic capacitors 63.

[0108] ○ The housing 11 may not have the protruding portion 32. ○ The heat dissipation member interposed between the protruding portion 32 and each electrolytic capacitor 63 is not limited to the heat dissipation grease 19. The heat dissipation member may be, for example, a heat dissipation sheet.

[0109] ○ A heat dissipation member may not be provided between the protruding portion 32 and each electrolytic capacitor 63. In this case, it is preferable that each electrolytic capacitor 63 is in contact with the protruding portion 32. ○ The inverter 16 may not have the holder 65.

[0110] ○ When the plurality of electrolytic capacitors 63 are arranged between the third component 23 and the circuit board 66 in the axial direction of the motor housing 24, the holder 65 may also be arranged between the third component 23 and the circuit board 66 in the axial direction of the motor housing 24. The plurality of electrolytic capacitors 63 may be held on the surface of the holder 65 on the third component 23 side.

[0111] ○ The capacitor holding portion 72 may be separate from the base plate 71. ○ As described above, the first electrolytic capacitor 63a does not necessarily need to be arranged such that the distance from the negative electrode base end portion 69a to the circuit board 66 is shorter than the distance from the positive electrode base end portion 68a to the circuit board 66. In this case, the distance between the positive electrode lead insertion hole 75 through which the positive electrode lead 68 of the first electrolytic capacitor 63a is inserted and the negative electrode lead insertion hole 76 through which the negative electrode lead 69 of the first electrolytic capacitor 63a is inserted does not necessarily need to be shorter than the distance between the positive electrode base end portion 68a and the negative electrode base end portion 69a.

[0112] ○ The positive electrode lead 68 and the negative electrode lead 69 of the electrolytic capacitor 63 may each be connected to the circuit board 66 on the first surface 66a of the circuit board 66. ○ A part of the first electrolytic capacitor 63a and a part of the second electrolytic capacitor 63b do not necessarily need to overlap in the width direction of the protruding portion 32.

[0113] ○ A part of the first electrolytic capacitor 63a and a part of the second electrolytic capacitor 63b do not necessarily need to overlap in the axial direction of the motor housing 24. ○ The electrolytic capacitor 63 may be arranged such that the distance from the first end face 67a of the capacitor body 67 to the suction port 11a is equal to or greater than the distance from the second end face 67b of the capacitor body 67 to the suction port 11a.

[0114] ○ The layout of the three-phase switching element 61, the coil 62, the plurality of electrolytic capacitors 63, and the three-phase conductive member 64 in the holder 65 may be appropriately changed. ○ The electrolytic capacitor 63 may be arranged such that the distance from the first end face 67a of the capacitor body 67 to the switching element 61 is equal to or greater than the distance from the second end face 67b of the capacitor body 67 to the switching element 61.

[0115] ○ The holder 65 does not necessarily need to have the cover portion 74. ○ If the positive electrode lead 68 and the negative electrode lead 69 of the first electrolytic capacitor 63a and the positive electrode lead 68 and the negative electrode lead 69 of the second electrolytic capacitor 63b do not interfere with each other, the first electrolytic capacitor 63a and the second electrolytic capacitor 63b do not have to be arranged offset in the axial direction of the electrolytic capacitor 63.

[0116] ○ The compression part 14 is not limited to the scroll type. The compression part 14 may be, for example, a piston type, a vane type, or the like. ○ The electric compressor 10 may be used for applications other than vehicle air conditioners. For example, the electric compressor 10 may be mounted on a fuel cell vehicle. The electric compressor 10 is used to compress air as a fluid supplied to the fuel cell by the compression part 14.

Description of reference numerals

[0117] 10… Electric compressor, 11… Housing, 14… Compression part, 15… Electric motor, 16… Inverter, 24… Motor housing, 25… Inverter housing, 28… Closing part as a partition wall, 32… Protrusion, 63… Electrolytic capacitor, 63a… First electrolytic capacitor, 63b… Second electrolytic capacitor, 65… Holder, 66… Circuit board, 66a… First surface, 66b… Second surface, 67… Capacitor body, 67a… First end face as one end face, 68… Positive electrode lead, 68a… Positive electrode base end part, 69… Negative electrode lead, 69a… Negative electrode base end part, 75… Positive electrode lead insertion hole, 76… Negative electrode lead insertion hole, S1… Inverter accommodation chamber, S2… Suction chamber.

Claims

1. a compression unit that compresses a fluid; an electric motor that drives the compression unit; an inverter that drives the electric motor; a cylindrical motor housing that houses the electric motor and partitions an intake chamber into which the fluid is inhaled, an inverter housing that partitions an inverter housing chamber that houses the inverter, and a metal housing having a partition wall that separates the intake chamber and the inverter housing chamber; comprising; the inverter has a circuit board arranged such that the plate thickness direction coincides with the axial direction of the motor housing, and a plurality of electrolytic capacitors; each of the plurality of electrolytic capacitors has a cylindrical capacitor body, a positive electrode lead and a negative electrode lead that extend from one end surface in the axial direction of the capacitor body and are connected to the circuit board; the axial directions of the plurality of electrolytic capacitors extend in parallel in a direction intersecting the axial direction of the motor housing; the plurality of electrolytic capacitors are arranged in a stacked state in the axial direction of the motor housing such that a plurality of the electrolytic capacitors are located in each stage; in each stage, the plurality of electrolytic capacitors are arranged at intervals in a direction orthogonal to the axial direction of the electrolytic capacitor; a motor compressor in which the intervals between the electrolytic capacitors in each stage gradually widen from one side to the other side in the axial direction of the motor housing, when, among the plurality of electrolytic capacitors, the electrolytic capacitor in the stage closer to the circuit board is defined as a first electrolytic capacitor and the electrolytic capacitor in the stage farther from the circuit board is defined as a second electrolytic capacitor, the second electrolytic capacitor is arranged such that the distance from the negative electrode base end portion of the negative electrode lead to the circuit board in the axial direction of the motor housing is shorter than the distance from the positive electrode base end portion of the positive electrode lead to the circuit board in the axial direction of the motor housing. An electric compressor characterized by that.

2. the inverter has a holder that is arranged between the partition wall and the circuit board in the axial direction of the motor housing and holds the plurality of electrolytic capacitors; the plurality of electrolytic capacitors are arranged between the partition wall and the holder in the axial direction of the motor housing; The electric compressor according to claim 1, wherein the intervals between the electrolytic capacitors in each stage gradually widen from the circuit board side toward the partition wall side in the axial direction of the motor housing.

3. The electric compressor according to claim 2, wherein the housing has a protruding portion that protrudes from the partition wall toward the plurality of electrolytic capacitors and is surrounded by the plurality of electrolytic capacitors.

4. The inverter is disposed between the partition wall and the circuit board in the axial direction of the motor housing and has a holder that holds the plurality of electrolytic capacitors. The plurality of electrolytic capacitors are disposed between the partition wall and the holder in the axial direction of the motor housing. The holder has a positive electrode lead insertion hole through which the positive electrode lead of the second electrolytic capacitor is inserted and a negative electrode lead insertion hole through which the negative electrode lead of the second electrolytic capacitor is inserted. The electric compressor according to any one of claims 1 to 3, wherein the distance between the positive electrode lead insertion hole and the negative electrode lead insertion hole is shorter than the distance between the positive electrode base end portion and the negative electrode base end portion.

5. The circuit board has a first surface facing the holder and a second surface on the side opposite to the first surface. The electric compressor according to claim 4, wherein the positive electrode lead and the negative electrode lead each penetrate the circuit board and are connected to the circuit board on the second surface of the circuit board.

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