Electric compressor

Abstract

The present invention provides an electric compressor that ensures sufficient creepage distance, suppresses increases in size, and prevents a decrease in the heat dissipation performance of the power elements. [Solution] The electric compressor includes an inverter 30 housed in an inverter housing 20. The inverter 30 includes a circuit board, a power element 40, and a metal base substrate 50. The power element 40 includes a molded portion 41 and leads 42 that are exposed from the terminal side surface 411 and connected to a circuit pattern formed on the circuit board. The leads 42 include a first portion 421 and a second portion 422. The metal base substrate 50 is provided between the power element 40 and the inverter housing 20. The metal base substrate 50 includes a metal layer 51 and an insulating layer 52 integrally formed on one surface of the metal layer 51. The insulating layer 52 includes a molded portion 521 facing the molded portion 41 and a leaded portion 522 extending from the molded portion 521.

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses an inverter-integrated electric compressor in which an inverter device and an electric compressor are integrated. The inverter device is incorporated into an inverter housing, which is an inverter housing provided in the housing of the electric compressor. The inverter device includes an IGBT (Insulated Gate Bipolar Transistor), which is a power element, a power board, which is a circuit board, and a metal plate that functions as a heat sink fixed to the inverter housing. The IGBT includes a molded portion molded by resin and a terminal, which is a lead extending from the side surface of the molded portion. The molded portion is installed on the metal plate and is connected to the power board by the terminal. The metal plate radiates heat generated by the IGBT to the inverter housing. The IGBT is fixed to the metal plate via an insulating sheet.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] With the spread of electric vehicles, the power supply voltage of the electric compressor mounted on the electric vehicle has been increased to a high voltage such as 800 [V]. Therefore, it is necessary to ensure the insulation distance and the creepage distance from the lead to the metal plate.

[0005] In the configuration described in Patent Document 1 above, it is possible to secure an insulation distance from the lead to the metal plate equal to the thickness of the insulating sheet. However, in this configuration, there is a risk that the creepage distance from the lead to the metal plate cannot be secured. If the thickness of the insulating sheet is increased to secure the creepage distance from the lead to the metal plate, it leads to an increase in the size of the electric compressor and a decrease in the heat dissipation performance of the power element. For this reason, in electric compressors, it is desirable to secure the creepage distance, suppress an increase in the thickness of the electric compressor, and suppress a decrease in the heat dissipation performance of the power element. [Means for solving the problem]

[0006] An electric compressor for solving the above problems comprises a compression section for compressing a fluid, an electric motor for driving the compression section, an inverter for driving the electric motor, and an inverter housing for housing the inverter, wherein the inverter comprises a circuit board on which a circuit pattern constituting the circuit of the inverter is formed, a molded section in which switching elements constituting the circuit of the inverter are molded in resin, and a power element having a plurality of leads exposed from the side surface of the molded section and electrically connected to the circuit pattern, wherein each of the plurality of leads has a first portion extending outward from the side surface, and a second portion bending from the first portion and extending toward the circuit board, and the electric compressor is such that the above The inverter further comprises a metal base substrate provided between the power element and the inverter housing, the metal base substrate comprising a metal layer that dissipates heat generated from the power element to the inverter housing, and an insulating layer integrally formed on one surface of the metal layer, the power element and the metal base substrate being housed in the inverter housing such that the first portion, the insulating layer, and the metal layer are arranged in this order with respect to the thickness direction of the metal base substrate, and the insulating layer comprises a mold-facing portion extending opposite to the mold portion in the thickness direction, and a lead-facing portion extending from the mold-facing portion so as to be opposite to at least the first portion in the thickness direction.

[0007] According to this, the electric compressor insulates the lead and the metal layer with an insulating layer, while transferring the heat generated by the power element to the inverter housing via a metal base substrate. For example, in an inverter without a metal base substrate, the inverter housing is equipped with a heat sink to dissipate heat from the power element. In such an inverter, the heat sink may be insulated from the power element by providing a sheet made of insulating material separate from the heat sink. Compared to this case, the electric compressor, by having the inverter equipped with a metal base substrate having a metal layer and an insulating layer integrally formed on the metal layer, can suppress an increase in the thickness of the metal base substrate.

[0008] Furthermore, by providing mold-facing and lead-facing portions in the insulating layer, the creepage distance between the leads and the metal layer can be increased. For example, compared to increasing the creepage distance by making the insulating layer thicker, the electric compressor can suppress the increase in size in the thickness direction of the metal base substrate. Also, by increasing the creepage distance with the mold-facing and lead-facing portions, the electric compressor can suppress the decrease in heat dissipation performance of the power elements by the insulating layer, compared to increasing the creepage distance by making the insulating layer thicker. As described above, the electric compressor can ensure creepage distance, suppress increase in size, and suppress the decrease in heat dissipation performance of the power elements.

[0009] In an electric compressor, the molded portion is provided with a heat sink for dissipating heat from the switching element, and the molded portion opposite to the heat sink is preferably interposed between the heat sink and the metal layer. According to this, the metal base substrate has a mold-facing portion between the mold portion and the metal layer. For example, in power elements such as IGBTs and IPMs (Intelligent Power Modules), a heat sink may be provided on the opposite side of the surface facing the circuit board. Even when an electric compressor is equipped with a power element that has a heat sink, it is possible to insulate the power element from the metal layer and maintain creepage distance between the leads and the metal layer while suppressing an increase in size.

[0010] In an electric compressor, the metal base substrate further comprises an element-side metal layer provided on the opposite side of the metal layer with the insulating layer in between, and the power element and the metal base substrate are housed in the inverter housing such that the mold portion, the element-side metal layer, the insulating layer, and the metal layer are arranged in this order with respect to the thickness direction of the metal base substrate, the mold-facing portion is outside the element-side metal layer and faces the mold portion in the thickness direction, and the lead-facing portion is outside the element-side metal layer and extends from the mold-facing portion so as to face at least the first portion in the thickness direction.

[0011] According to this, in the thickness direction of the metal base substrate, the molded portion faces the element-side metal layer in some areas, while facing the molded portion in other areas. The leads also face the lead-facing portions extending from the molded portion. In other words, the power element has its leads and the portion of the molded portion closer to the leads outside the element-side metal layer. This increases the insulation distance between the leads and the element-side metal layer. In the inverter housing, the power element allows heat dissipation from the molded portion to the insulating layer and metal layer via the element-side metal layer, while also increasing the creepage distance between each of the metal layer and the element-side metal layer and the leads. As a result, the electric compressor can achieve both heat dissipation by the element-side metal layer and the securing of creepage distance between each of the metal layer and the element-side metal layer and the leads.

[0012] In an electric compressor, the molded portion is provided with a heat sink for dissipating heat from the switching element, and the heat sink is preferably soldered to the element-side metal layer. According to this, the inverter can be made smaller compared to, for example, a case where power elements are attached to a metal base substrate using leaf springs.

[0013] Furthermore, the heat generated from the power element is transferred to the element-side metal layer via the heat sink and solder. In other words, the inverter can improve heat dissipation performance compared to cases where the power element is attached to a metal base substrate by, for example, pressing with a leaf spring.

[0014] In an electric compressor, the element-side metal layer may include an outer mold portion that extends outward from the mold portion in the direction in which the plurality of leads are aligned. According to this, the element-side metal layer includes an outer mold portion, which is the part that does not overlap with the mold portion when viewed in a plan view from the thickness direction of the metal base substrate. By including this outer mold portion, the element-side metal layer can increase its heat capacity by the amount of this outer mold portion. In other words, by including this outer mold portion in the element-side metal layer, the electric compressor can improve the cooling performance of the power element.

[0015] Furthermore, the heat generated in the power element is transferred to a portion of the element-side metal layer that is different from the outer mold portion, and then transferred to the outer mold portion. For example, even if a rapid temperature rise occurs in the power element when an electric compressor is started, the element-side metal layer can retain heat at the outer mold portion and dissipate heat to the metal layer via the insulating layer. Therefore, even if a rapid temperature rise occurs in the power element, the element-side metal layer can suppress heat accumulation due to heat absorption exceeding heat dissipation. As described above, by providing an outer mold portion on the element-side metal layer of the metal base substrate, the cooling performance of the power element can be improved.

[0016] In an electric compressor, the element-side metal layer may include an outer mold projection that extends further from the outer mold portion in the direction in which the first portion extends, such that the outer mold projection is adjacent to the mold-facing portion and the lead-facing portion in the direction in which the plurality of leads are aligned.

[0017] According to this, the element-side metal layer includes a mold outer protrusion extending from the outer part of the mold, and thus can increase the heat capacity compared to the case without the mold outer protrusion. That is, the electric compressor can improve the cooling performance of the power element by including the mold outer protrusion in the element-side metal layer.

[0018] In the electric compressor, it is preferable that the metal base substrate is provided with a temperature sensor that measures the temperature of the power element and is electrically connected to the circuit board. According to this, the temperature of the power element is measured by the temperature sensor provided on the metal base substrate. For example, compared with the case where the temperature sensor is mounted on the circuit board, the temperature sensor can measure the temperature of the power element at a location closer to the power element, so that the measurement accuracy of the temperature can be improved.

Advantages of the Invention

[0019] According to the present invention, it is possible to suppress the increase in size and the decrease in heat dissipation of the power element, including ensuring the creepage distance.

Brief Description of the Drawings

[0020] [Figure 1] FIG. 1 is a schematic diagram showing an overview of an electric compressor and a vehicle air conditioner. [Figure 2] FIG. 2 is an exploded perspective view showing a circuit board, a power element, and a metal base substrate. [Figure 3] FIG. 3 is a perspective view showing a power element and a metal base substrate. [Figure 4] FIG. 4 is a cross-sectional view showing a power element and a metal base substrate. [Figure 5] FIG. 5 is a top view showing a circuit board, a power element, and a metal base substrate.

Embodiments for Carrying Out the Invention

[0021] The following describes one embodiment of an electric compressor. The electric compressor of this embodiment is used in a vehicle air conditioning system mounted on a vehicle. <Vehicle air conditioning system> As shown in Figure 1, the vehicle air conditioning system 100 comprises an electric compressor 10 and an external refrigerant circuit 101 that supplies a refrigerant as a fluid to the electric compressor 10. The vehicle air conditioning system 100 is mounted on a vehicle (not shown). The external refrigerant circuit 101 includes, for example, a heat exchanger and an expansion valve. The vehicle air conditioning system 100 provides heating and cooling to the interior of the vehicle by compressing the refrigerant with the electric compressor 10 and by heat exchange and expansion of the refrigerant with the external refrigerant circuit 101.

[0022] The vehicle air conditioning system 100 is equipped with an air conditioning ECU 102 that controls the entire vehicle air conditioning system 100. The air conditioning ECU 102 is configured to understand parameters such as the interior temperature and the set temperature, and based on these parameters, it transmits various commands such as ON / OFF commands to the electric compressor 10.

[0023] <Overall view of an electric compressor> The electric compressor 10 comprises a housing 11, a compression unit 12, an electric motor 13, an inverter housing 20, and an inverter 30. The electric compressor 10 is electrically connected to an onboard power supply E and is driven by the power supply E. In this embodiment, the voltage of the power supply E is 800[V].

[0024] The housing 11 is generally cylindrical in shape. The housing 11 is made of a heat-conducting material. One example of a material used to form the housing 11 is aluminum. The housing 11 has an inlet 11a and an outlet 11b. Refrigerant is drawn into the housing 11 from the external refrigerant circuit 101 through the inlet 11a. The refrigerant drawn into the housing 11 is discharged to the outside of the housing 11 through the outlet 11b. The outlet 11b is formed at one end of the housing 11 in the axial direction. The inlet 11a is formed near the end opposite to the end where the outlet 11b is formed.

[0025] The compression unit 12 is housed in the housing 11. The compression unit 12 compresses the fluid. In this embodiment, the compression unit 12 compresses the refrigerant drawn into the housing 11 from the intake port 11a. The compression unit 12 discharges the compressed refrigerant from the discharge port 11b. The specific configuration of the compression unit 12 is arbitrary. Examples of specific configurations of the compression unit 12 include scroll type, piston type, and vane type.

[0026] The electric motor 13 comprises a rotating shaft 14, a rotor 15, and a stator 16. The electric motor 13 is housed in a housing 11. The electric motor 13 drives the compression section 12. The rotating shaft 14 is a cylindrical body rotatably supported relative to the housing 11. The axial direction of the rotating shaft 14 coincides with the axial direction of the housing 11. The rotor 15 is a cylindrical body fixed to the housing 11. Permanent magnets (not shown) are embedded in the rotor 15.

[0027] The stator 16 comprises a stator core 17 and a coil 18. The stator 16 is fixed to the housing 11. The stator core 17 faces the rotor 15 in the radial direction of the rotation axis 14. The stator core 17 is a cylindrical body fixed to the housing 11. The axial direction of the stator core 17 coincides with the axial direction of the rotation axis 14. Teeth 17a are formed on the inner circumferential surface of the stator core 17. The coil 18 is wound around the teeth 17a. The electric motor 13 in this embodiment is a three-phase motor. That is, the coil 18 has a three-phase structure consisting of a U-phase coil, a V-phase coil, and a W-phase coil.

[0028] The inverter housing 20 comprises an inverter plate 21 and an inverter cover 22. The inverter housing 20 is attached to the housing 11. Specifically, the inverter housing 20 is attached to the axial end of the housing 11 opposite the end where the discharge port 11b is formed.

[0029] The inverter plate 21 is a plate-like body with its thickness oriented in the axial direction of the housing 11. The inverter cover 22 is attached to the housing 11 via the inverter plate 21. More specifically, the inverter cover 22 is attached to the end of the housing 11 in the axial direction of the housing 11, with the inverter plate 21 interposed between the inverter cover 22 and the housing 11. The inverter plate 21 and the inverter cover 22 are fixed to the housing 11 by bolts 23.

[0030] The inverter housing 20 is provided with a housing space 20a. The housing space 20a is defined by the inverter plate 21 and the inverter cover 22. <Inverter> The inverter 30 comprises a circuit board 31, a control unit 33, a plurality of power elements 40, a metal base substrate 50, and a temperature sensor 70. The inverter 30 is housed in the inverter housing 20. The inverter 30 is positioned in the housing space 20a. In other words, the circuit board 31, the power elements 40, and the metal base substrate 50 are housed in the inverter housing 20. The inverter 30 is fixed to the housing 11 by the inverter housing 20.

[0031] The inverter 30 is cooled by the refrigerant drawn into the housing 11 through the intake port 11a. More specifically, the heat generated in the inverter 30 is transferred to the housing 11 via the inverter housing 20. The heat transferred to the housing 11 is then transferred to the refrigerant inside the housing 11. In other words, the inverter 30 transfers the heat it generates to the refrigerant via the inverter housing 20 and the housing 11.

[0032] The inverter 30 drives the electric motor 13. The inverter 30 is configured to convert the DC power input from the power source E into AC power and then output it to the electric motor 13. More specifically, the inverter 30 is electrically connected to the power source E via an external connector C provided on the inverter cover 22. The inverter 30 is also electrically connected to the coil 18 of the electric motor 13 via connectors and wiring (not shown) and outputs AC power to the coil 18. The inverter 30 is connected to the air conditioning ECU 102 via the external connector C.

[0033] The circuit board 31 is a thin plate-like body. The thickness direction of the circuit board 31 coincides with the axial direction of the housing 11. Power elements 40 and various electronic components (not shown) are mounted on the circuit board 31.

[0034] A circuit pattern 32, which constitutes the circuit of the inverter 30, is formed on the circuit board 31. The circuit pattern 32 is formed on the surface of the circuit board 31 facing the inverter cover 22 in the thickness direction of the board. The circuit pattern 32 is electrically connected to the external connector C. In addition, the power elements 40 and various electronic components mounted on the circuit board 31 are electrically connected to each other by the circuit pattern 32. Power is supplied to the circuit pattern 32 from the power supply E via the external connector C. The power supplied via the external connector C is supplied to the power elements 40 and various electronic components via the circuit pattern 32.

[0035] The control unit 33 is mounted on the circuit board 31. The control unit 33 is electrically connected to the circuit pattern 32. The control unit 33 is electrically connected to the power element 40 and various electrical components via the circuit pattern 32. The control unit 33 is configured to control the power element 40. The control unit 33 controls the inverter 30 by controlling the operation of the power element 40.

[0036] The control unit 33 is implemented, for example, by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Furthermore, some or all of these components may be implemented by hardware (including circuitry) such as an LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), or GPU (Graphics Processing Unit), or by the collaboration of software and hardware. The program may be pre-stored in a storage device equipped with a non-transient storage medium, such as flash memory, provided by the electric compressor 10.

[0037] <Power element> The power element 40 is located in the housing space 20a. The power element 40 is located between the circuit board 31 and the inverter plate 21 within the housing space 20a. The power element 40 in this embodiment is a discrete IGBT. The power element 40 is controlled on and off by the control unit 33. The power element 40 in this embodiment also has a built-in freewheeling diode. However, the power element 40 does not necessarily have to have a built-in freewheeling diode. In this case, the inverter 30 is equipped with a freewheeling diode corresponding to the power element 40.

[0038] The inverter 30 is equipped with multiple power elements 40. The inverter 30 converts the input power by controlling the on / off state of the multiple power elements 40. Note that in Figures 1 to 5, only one of the multiple power elements 40 equipped with the inverter 30 is shown. The number of power elements 40 is appropriately changed according to the configuration of the electric motor 13 driven by the inverter 30. The electric motor 13, which is a three-phase motor in this embodiment, is equipped with six power elements 40.

[0039] As shown in Figures 1 and 2, the power element 40 has a molded portion 41 and a plurality of leads 42. In this embodiment, the power element 40 has three leads 42 as shown in Figure 2. Note that the number of leads 42 is not limited to three and can be appropriately changed depending on the specific configuration of the power element 40. In this embodiment, the three leads 42 function as a gate terminal, a collector terminal, and an emitter terminal, respectively. The lead 42 that functions as a gate terminal is connected to the control unit 33 shown in Figure 1 via a circuit pattern 32. The power element 40 switches between an on state and an off state based on a signal input from the control unit 33 to the lead 42 that functions as a gate terminal.

[0040] As shown in Figure 2, the molded portion 41 is a block-shaped body. As shown in Figure 1, the molded portion 41 is formed by molding the switching element S that constitutes the circuit of the inverter 30 with resin A. Specifically, the molded portion 41 is formed by including the switching element S inside and filling the space containing the switching element S with resin A. Switching between the on state and the off state of the power element 40 is achieved by the switching operation of the switching element S. The heat generated in the switching element S by this switching operation is transferred to the outside of the molded portion 41 via resin A.

[0041] The power element 40 is housed in the inverter housing 20 while aligning the thickness direction of the molded portion 41 with the thickness direction of the circuit board 31 and the inverter plate 21. In other words, of the two surfaces of the molded portion 41 in the thickness direction, one surface faces the inverter plate 21, and the other surface faces the circuit board 31.

[0042] As shown in Figures 1 and 2, the molded portion 41 is equipped with a heat sink 43. The heat sink 43 is a plate-shaped body made of a metal material. The heat sink 43 is integrated with the molded portion 41. The heat sink 43 is incorporated into the molded portion 41. Although not shown in detail, the heat sink 43 is equipped with a heat dissipation surface 431 that is exposed to the outside of the molded portion 41. The heat dissipation surface 431 is exposed on one side of the molded portion 41 in the thickness direction. The heat dissipation surface 431 is flush with that one side of the molded portion 41.

[0043] The molded portion 41 has a heat sink 43 exposed on the side opposite to the side facing the circuit board 31. In other words, the heat sink surface 431 faces the inverter plate 21 in the thickness direction of the molded portion 41.

[0044] The heat sink 43 dissipates heat from the switching element S. Specifically, when the switching element S generates heat inside the molded portion 41, the heat from the switching element S is transferred to the heat sink 43 through the resin A filled in the molded portion 41. The heat sink 43 then dissipates this heat from its heat dissipation surface 431 to the outside of the power element 40.

[0045] The lead 42 is provided on the molded portion 41. The lead 42 is made of a conductive material. The lead 42 extends from the side surface of the molded portion 41. Inside the molded portion 41, the lead 42 is electrically connected to the switching element S and extends from the inside to the outside of the molded portion 41 via the terminal side surface 411, which is the side surface of the molded portion 41.

[0046] The three leads 42 extend from the terminal side surface 411. The terminal side surface 411 is one of the sides of the molded portion 41. More specifically, the terminal side surface 411 is one of the surfaces of the molded portion 41 that are parallel to the thickness direction of the molded portion 41.

[0047] Hereafter, the direction perpendicular to the terminal side surface 411 will be referred to as the first direction D1. The direction perpendicular to the thickness direction of the molded portion 41 and the first direction D1 will be referred to as the second direction D2. The three leads 42 are aligned in one direction on the terminal side surface 411. The three leads 42 shown in Figure 2 are aligned in the second direction D2 on the terminal side surface 411.

[0048] Each of the three leads 42 is electrically connected to the circuit pattern 32. The leads 42 are electrically connected to the circuit board 31 in the portion extending from the molded portion 41. The leads 42 also electrically connect the switching element S inside the power element 40 to the circuit board 31. Hereafter, in the portion of the lead 42 extending from the molded portion 41, the end closer to the terminal side 411 will be referred to as the base end, and the portion closer to the circuit board 31 will be referred to as the tip end.

[0049] Each of the three leads 42 comprises a first portion 421 and a second portion 422. The lead 42 has the first portion 421 and the second portion 422 in the portion that extends from the inside to the outside of the molded portion 41. The first portion 421 is the portion of the lead 42 closer to the base end. The first portion 421 extends from the side of the molded portion 41 to the outside. The first portion 421 can also be described as the portion of the lead 42 that is erected on the terminal side surface 411. The first portion 421 extends in the first direction D1.

[0050] The second portion 422 is the part of the lead 42 closer to the tip. The second portion 422 bends from the first portion 421 and extends toward the circuit board 31. The second portion 422 can also be described as the part of the lead 42 that is closer to the circuit board 31.

[0051] The lead 42 penetrates the circuit board 31 via the second portion 422, and its tip protrudes from the opposite side of the circuit board 31 from the side facing the molded portion 41. As a result, the lead 42 is connected to the circuit pattern 32 at the portion near the tip that protrudes from the circuit board 31.

[0052] <Metal-based substrate> As shown in Figure 1, the metal base substrate 50 comprises a metal layer 51, an insulating layer 52, and an element-side metal layer 53. The metal base substrate 50 is in sheet form. The metal base substrate 50 is housed in the housing space 20a. The metal base substrate 50 is provided between the power element 40 and the inverter housing 20. More specifically, the metal base substrate 50 is provided between the power element 40 and the inverter plate 21. The metal base substrate 50 is installed on the inverter plate 21 with its thickness direction matching the thickness direction of the inverter plate 21. That is, the thickness direction of the metal base substrate 50 matches the thickness direction of the inverter plate 21, the molded portion 41, and the circuit board 31. The metal base substrate 50 has one surface facing the inverter plate 21 in the thickness direction, and the other surface facing the power element 40.

[0053] In the metal base substrate 50, the metal layer 51, the insulating layer 52, and the element-side metal layer 53 are laminated in this order. The metal base substrate 50 is formed by integrating the metal layer 51, the insulating layer 52, and the element-side metal layer 53. In the metal base substrate 50 of this embodiment, the metal layer 51 is 1.0 [mm], the insulating layer 52 is 0.15 [mm], and the element-side metal layer 53 is 0.035 [mm]. Note that the thickness of the metal base substrate 50 in Figures 1 to 5 is exaggerated to facilitate the illustration of the structure in the thickness direction of the metal base substrate 50.

[0054] <Metal layer> As shown in Figures 1 and 2, the metal layer 51 constitutes a portion of the metal base substrate 50 that is closer to one side in the thickness direction. More specifically, the metal layer 51 constitutes a portion of the metal base substrate 50 that is closer to the inverter plate 21 in the thickness direction. The metal base substrate 50 faces the inverter plate 21 at the metal layer 51.

[0055] The metal layer 51 is formed of a heat-conducting metallic material. In this embodiment, the material forming the metal layer 51 is aluminum. The metal base substrate 50 brings the metal layer 51 into contact with the inverter plate 21. Therefore, the metal base substrate 50 is heat-conductively connected to the inverter plate 21 at the metal layer 51.

[0056] <Insulating layer> The insulating layer 52 is integrally formed on one surface of the metal layer 51. The insulating layer 52 is formed on the surface of the metal layer 51 opposite to the surface in contact with the inverter plate 21 in the thickness direction of the metal base substrate 50. The insulating layer 52 is interposed between the metal layer 51 and the power element 40 in the thickness direction of the metal base substrate 50. More specifically, the insulating layer 52 is interposed between the metal layer 51 and the molded portion 41 in the thickness direction of the metal base substrate 50. The insulating layer 52 is interposed between the heat sink 43 and the metal layer 51.

[0057] The insulating layer 52 is interposed between the metal layer 51 and the first portion 421 of the lead 42 in the thickness direction of the metal base substrate 50. In other words, the power element 40 and the metal base substrate 50 are housed in the inverter housing 20 such that the first portion 421, the insulating layer 52, and the metal layer 51 are arranged in this order with respect to the thickness direction of the metal base substrate 50.

[0058] The insulating layer 52 comprises a mold-facing portion 521 and a lead-facing portion 522. The insulating layer 52 is formed of an insulating material. In this embodiment, the insulating layer 52 is made of a resin material. The insulating layer 52 insulates the power element 40 from the metal layer 51.

[0059] The mold-facing portion 521 is a part of the insulating layer 52. The mold-facing portion 521 extends so as to face the mold portion 41 in the thickness direction of the metal base substrate 50. The mold-facing portion 521 is interposed between the heat sink 43 and the metal layer 51. In this embodiment, the mold-facing portion 521 constitutes the entire portion of the insulating layer 52 that is aligned with the mold portion 41 in the thickness direction of the metal base substrate 50. The lead-facing portion 522 is a part of the insulating layer 52. The lead-facing portion 522 extends from the mold-facing portion 521 so as to face at least the first portion 421 in the thickness direction of the metal base substrate 50.

[0060] The area in which the insulating layer 52 is provided on the metal layer 51 will be explained below using Figures 3 and 4. In the following explanation, we consider a virtual plane P that is partially formed by the terminal side surface 411. The virtual plane P only needs to be partially formed by the terminal side surface 411, and the area of ​​the virtual plane P only needs to be large enough to intersect with the metal base substrate 50. In other words, the area of ​​the virtual plane P is not limited to that shown in Figures 3 and 4.

[0061] The virtual plane P intersects with the metal base substrate 50. In other words, the virtual plane P intersects with the metal layer 51 and the insulating layer 52. In Figures 3 and 4, the portion where the virtual plane P intersects with the insulating layer 52 is indicated by a virtual line L. That is, the virtual line L is a straight line on the virtual plane P and on the insulating layer 52. The virtual line L extends in the second direction D2.

[0062] The virtual plane P extends in directions parallel to the thickness direction of the molded portion 41 and the thickness direction of the metal base substrate 50. Therefore, in a plan view from the thickness direction of the metal base substrate 50, the virtual plane P and the virtual line L coincide. In other words, in this plan view, the terminal side surface 411 coincides with the virtual line L.

[0063] In the insulating layer 52, the virtual line L corresponds to the boundary line between the mold-facing portion 521 and the lead-facing portion 522. Specifically, in the first direction D1, the insulating layer 52 has a mold-facing portion 521 closer to the mold-facing portion 41 than the virtual line L, and a lead-facing portion 522 closer to the lead 42 than the virtual line L. The mold-facing portion 521 extends from the virtual line L and corresponds to the portion of the insulating layer 52 that is aligned with the mold-facing portion 41 in the thickness direction of the metal base substrate 50. In other words, only the portion of the mold-facing portion 521 closer to the virtual line L is shown in Figure 3.

[0064] The insulating layer 52 extends from a virtual line L where the virtual plane P including the terminal side surface 411 intersects the metal base substrate 50, so as to face at least the first portion 421 in the thickness direction. In other words, the metal base substrate 50 has a lead-facing portion 522 in the insulating layer 52 such that it overlaps with at least the first portion 421 in a plan view from the thickness direction. It can also be said that the insulating layer 52 has a lead-facing portion 522 that extends from the virtual line L so as to insulate at least the first portion 421 from the metal layer 51. Furthermore, the metal base substrate 50 has a mold-facing portion 521 in the insulating layer 52 such that it overlaps with at least the mold portion 41 in a plan view from the thickness direction. It can also be said that the insulating layer 52 has a mold-facing portion 521 so as to insulate at least the portion of the mold portion 41 closer to the lead 42 from the metal layer 51.

[0065] As described above, the insulating layer 52 is formed on the metal layer 51 so as to insulate at least the first portion 421 from the metal layer 51. The insulating layer 52 may be formed on the entire surface of the metal layer 51 opposite to the surface in contact with the inverter plate 21. Alternatively, the insulating layer 52 may be formed partially on the opposite surface of the metal layer 51. When the insulating layer 52 is formed partially on the opposite surface, multiple insulating layers 52 are formed so as to insulate each of the multiple power elements 40 from the first portion 421 and the metal layer 51.

[0066] In short, the insulating layer 52 may be formed on any position on the metal layer 51 opposite to the surface in contact with the inverter plate 21, as long as it insulates the first portion 421 from the metal layer 51. In this embodiment, the insulating layer 52 is formed over the entire surface of the metal layer 51 opposite to the above-mentioned surface. If multiple insulating layers 52 are formed on the metal layer 51, each insulating layer 52 includes a mold-facing portion 521 and a lead-facing portion 522.

[0067] Furthermore, if an insulating layer 52 is partially formed on the opposite side of the metal layer 51 as described above, the metal base substrate 50 is provided with an insulating layer 52 so as to insulate the first portion 421 from the metal layer 51. Specifically, the metal base substrate 50 is provided with an insulating layer 52 such that the spatial distance between the first portion 421 and the portion of the metal layer 51 not covered by the insulating layer 52 is greater than or equal to a desired distance. In other words, the area and arrangement of the insulating layer 52 on the metal base substrate 50 are set so that the spatial distance from each portion on the first portion 421 to the portion of the metal layer 51 not covered by the insulating layer 52 is greater than or equal to a desired distance. Here, each portion on the first portion 421 refers to the portion obtained when the first portion 421 is divided into multiple portions of arbitrary width in the direction in which the first portion 421 extends.

[0068] The desired distance in the spatial distance between the first portion 421 and the portion of the metal layer 51 not covered by the insulating layer 52 is appropriately changed according to the voltage of the power supply E, i.e., the voltage applied to the power element 40. In this embodiment, the insulating layer 52 is provided such that the spatial distance between the first portion 421 and the portion of the metal layer 51 not covered by the insulating layer 52 is 5 [mm] or more.

[0069] <Metal layer on the element side> As shown in Figures 1 and 2, the metal base substrate 50 has an element-side metal layer 53 on the opposite side of the metal layer 51, with an insulating layer 52 in between. The power element 40 and the metal base substrate 50 are housed in the inverter housing 20 such that the molded portion 41, the element-side metal layer 53, the insulating layer 52, and the metal layer 51 are arranged in this order in the thickness direction of the metal base substrate 50. In other words, the metal base substrate 50 has an insulating layer 52 interposed between the metal layer 51 and the element-side metal layer 53. It can also be said that the element-side metal layer 53 is provided on the metal layer 51 via the insulating layer 52.

[0070] The element-side metal layer 53 is provided on the insulating layer 52, and is located on the side of the insulating layer 52 opposite to the side facing the metal layer 51. The element-side metal layer 53 constitutes the portion of the metal base substrate 50 that faces the power element 40. In other words, the metal base substrate 50 faces the power element 40 via the element-side metal layer 53.

[0071] As shown in Figure 2, the element-side metal layer 53 comprises a main body portion 531, a molded outer portion 532 extending from the main body portion 531, and two molded outer protrusions 533 further extending from the molded outer portion 532. The element-side metal layer 53 is formed of a heat-conducting metal material. In this embodiment, the material forming the element-side metal layer 53 is copper. The element-side metal layer 53 is formed by molding a metal material. In other words, the main body portion 531, the molded outer portion 532, and the molded outer protrusions 533 are each a part of the element-side metal layer 53 made of a single metal material.

[0072] The element-side metal layer 53 has an edge portion 534. In a plan view of the metal base substrate 50 from the thickness direction, the edge portion 534 coincides with the boundary line between the element-side metal layer 53 and the insulating layer 52. In other words, the element-side metal layer 53 can be described as a portion surrounded by a closed edge portion 534.

[0073] As shown in Figure 1, a conductive member 54 is provided on the element-side metal layer 53. The conductive member 54 electrically connects the element-side metal layer 53 and the circuit board 31. An example of the conductive member 54 is a busbar. The conductive member 54 may also be a wire.

[0074] As shown in Figure 2, the element-side metal layer 53 has a main body portion 531 in the portion facing the molded portion 41 of the power element 40. In Figure 2, the boundary B between the main body portion 531 and the portion different from the main body portion 531 of the element-side metal layer 53 is shown by a dashed line. Boundary B is rectangular in shape. Boundary B is composed of two sides extending in the first direction D1 and two sides extending in the second direction D2. One of the four sides constituting boundary B coincides with a portion of the edge portion 534 when viewed from the thickness direction of the element-side metal layer 53. Boundary B coincides with a portion of the edge portion 534 when viewed from the thickness direction of the element-side metal layer 53 at one of the two sides extending in the second direction D2.

[0075] The main body portion 531 overlaps with the mold-facing portion 521 of the insulating layer 52 in the thickness direction of the element-side metal layer 53. Specifically, the portion of the insulating layer 52 that overlaps with the main body portion 531 in the thickness direction of the element-side metal layer 53 constitutes a part of the mold-facing portion 521. Therefore, it can be said that the mold-facing portion 521 faces the mold portion 41 in the portion closer to the imaginary line L in the first direction D1, while being covered by the element-side metal layer 53 in a portion other than that portion.

[0076] The element-side metal layer 53 is joined to the power element 40 at the main body portion 531. More specifically, the element-side metal layer 53 and the power element 40 are joined by the soldering of the heat sink 43 to the main body portion 531. In other words, the heat sink 43 is soldered to the element-side metal layer 53. In Figure 2, the portion of the element-side metal layer 53 where the solder is located is shown by a dashed line.

[0077] The terminal side surface 411 is positioned outside the element-side metal layer 53 such that a portion of the molded portion 41 faces the element-side metal layer 53, while the rest of the molded portion 41 and the lead 42 face the insulating layer 52. The molded portion 521 is located outside the element-side metal layer 53 and faces the molded portion 41 in the thickness direction of the metal base substrate 50. The lead portion 522 is located outside the element-side metal layer 53 and extends from the molded portion 521 so as to face at least the first portion 421 in the thickness direction of the metal base substrate 50.

[0078] In other words, the power element 40 has a portion in the thickness direction of the metal base substrate 50 that is aligned with the insulating layer 52 via the main body portion 531, and a portion that is aligned with the insulating layer 52 without the main body portion 531. Specifically, the power element 40 is aligned with the insulating layer 52 via the main body portion 531 in the portion of the molded portion 41 closest to the terminal side surface 411. The power element 40 is aligned with the molded opposing portion 521 in the portion of the molded portion 41 closest to the terminal side surface 411. Furthermore, the power element 40 is aligned with the lead opposing portion 522 on each of the leads 42. In other words, the power element 40 is provided on the element-side metal layer 53 such that, in a plan view of the metal base substrate 50 from the thickness direction, the terminal side surface 411 is outside the region enclosed by the edge portion 534.

[0079] The element-side metal layer 53 includes an outer mold portion 532 that extends outward from the mold portion 41 in the direction in which the multiple leads 42 are aligned. More specifically, the element-side metal layer 53 includes an outer mold portion 532 that extends from the boundary B of the main body portion 531. The outer mold portion 532 does not face the power element 40 in the thickness direction of the metal base substrate 50.

[0080] In this embodiment, the outer mold portion 532 extends from three sides of boundary B, excluding the side that coincides with the edge portion 534. The outer mold portion 532 surrounds the main body portion 531 along the three sides of boundary B, excluding the side that coincides with the edge portion 534. The outer mold portion 532 and the two outer mold protrusions 533 described below are separated by the extension of the side that coincides with the edge portion 534 of boundary B. The portion of the element-side metal layer 53 that combines the main body portion 531 and the outer mold portion 532 is rectangular in shape.

[0081] Each of the two mold outer protrusions 533 extends further in the direction in which the first portion 421 extends from the mold outer portion 532. More specifically, the mold outer protrusions 533 extend in the first direction D1 from the portion of the mold outer portion 532 that is closer to the lead 42 in the first direction D1. The mold outer protrusions 533 do not face the power element 40 in the thickness direction of the metal base substrate 50.

[0082] As shown in Figure 5, in a plan view of the metal base substrate 50 from the thickness direction, the two mold outer protrusions 533 extend from the mold outer portion 532 while being spaced apart from the lead 42 in the second direction D2. Specifically, the two mold outer protrusions 533 are spaced apart and aligned in the second direction D2. In the second direction D2, the lead 42 and the two mold outer protrusions 533 are aligned in the order of one mold outer protrusion 533, the lead 42, and the other mold outer protrusion 533. Therefore, when the metal base substrate 50 is viewed from the thickness direction, the mold opposing portion 521 and the lead opposing portion 522 of the insulating layer 52 are adjacent to each other and interposed between the two mold outer protrusions 533.

[0083] The element-side metal layer 53 is provided such that the spatial distance from the first portion 421 to the main body portion 531, the molded outer portion 532, and the molded outer protrusion portion 533 is greater than or equal to a desired distance. Specifically, the area and arrangement of the main body portion 531, the molded outer portion 532, and the molded outer protrusion portion 533 in the element-side metal layer 53 are set such that the spatial distance from each portion on the first portion 421 to these portions is greater than or equal to a desired distance. As a result, the element-side metal layer 53 and the lead 42 are insulated.

[0084] <Temperature sensor> As shown in Figures 1 and 2, the temperature sensor 70 is provided on the metal base substrate 50. The temperature sensor 70 measures the temperature of the power element 40. An example of the temperature sensor 70 is a thermistor. The temperature sensor 70 is provided on the element-side metal layer 53 of the metal base substrate 50. More specifically, the temperature sensor 70 is provided on the mold outer protrusion 533. The temperature sensor 70 is fixed to the mold outer protrusion 533 by soldering.

[0085] The temperature sensor 70 is mounted on the metal base substrate 50. The temperature sensor 70 is electrically connected to the element-side metal layer 53 of the metal base substrate 50. In other words, the temperature sensor 70 is electrically connected to the circuit board 31. More specifically, the temperature sensor 70 is electrically connected to the circuit pattern 32 via the element-side metal layer 53 and the conductive member 54. The temperature sensor 70 is connected to the control unit 33 shown in Figure 1 via the circuit pattern 32. The temperature sensor 70 is configured to transmit the measured temperature of the power element 40 to the control unit 33. For example, if the temperature of the power element 40 measured by the temperature sensor 70 becomes too high and exceeds a preset allowable value, the control unit 33 stops controlling the electric motor 13 by the inverter 30.

[0086] [Operation of this embodiment] The operation of this embodiment will now be explained. The electric compressor 10 compresses the refrigerant drawn into the housing 11 by a compression unit 12 driven by an electric motor 13. The electric compressor 10 converts DC power input from an external source into AC power using an inverter 30, and uses this AC power to drive the electric motor 13. The inverter 30 performs the conversion from DC power to AC power through the operation of power elements 40 mounted on a circuit board 31.

[0087] During the operation of the electric compressor 10, the power element 40 generates heat. The heat generated in the power element 40 is due to the switching element S contained in the molded portion 41 generating heat during this process. The heat generated in the power element 40 is transferred to the metal base substrate 50. In other words, the heat generated from the power element 40 is transferred to the element-side metal layer 53. In the metal base substrate 50, the heat transferred from the power element 40 reaches the metal layer 51 via the insulating layer 52. The metal layer 51 dissipates the heat generated from the power element 40 to the inverter housing 20. The inverter housing 20, having received this heat, is cooled by the coolant drawn into the housing 11.

[0088] DC power input to the electric compressor 10 is supplied to the switching element S in the molded portion 41 via the lead 42. The insulating layer 52 is provided with a mold-facing portion 521 and a lead-facing portion 522 extending from the mold-facing portion 521, respectively, facing the molded portion 41 and the first portion 421 in the thickness direction of the metal base substrate 50. As a result, the mold-facing portion 521 and the lead-facing portion 522 increase the creepage distance between the lead 42 and the metal layer 51.

[0089] [Effects of this embodiment] The effects of this embodiment will now be explained. (1) The electric compressor 10 insulates the lead 42 from the metal layer 51 with an insulating layer 52, and transmits the heat generated by the power element 40 to the inverter housing 20 via the metal base substrate 50. For example, in an inverter 30 that does not have a metal base substrate 50, the power element 40 may be insulated from the heat sink by providing a sheet made of an insulating material separate from the heat sink on the inverter plate 21. Compared to this case, the electric compressor 10 has a metal base substrate 50 which includes a metal layer 51 and an insulating layer 52 integrally formed with the metal layer 51, thereby enabling miniaturization of the metal base substrate 50 in the thickness direction.

[0090] Furthermore, the insulating layer 52 includes a mold-facing portion 521 and a lead-facing portion 522 that extends from the mold-facing portion 521 and faces the first portion 421. By including the mold-facing portion 521 and the lead-facing portion 522 in the insulating layer 52, the creepage distance between the lead 42 and the metal layer 51 can be increased. For example, compared to the case where the creepage distance is increased by making the insulating layer 52 thicker, the electric compressor 10 can suppress an increase in the thickness of the metal base substrate 50. By increasing the creepage distance with the mold-facing portion 521 and the lead-facing portion 522, the electric compressor 10 can suppress a decrease in the heat dissipation performance of the power element 40 compared to the case where the creepage distance is secured by making the insulating layer 52 thicker. As described above, the electric compressor 10 can secure the creepage distance, suppress an increase in size, and suppress a decrease in the heat dissipation performance of the power element 40.

[0091] (2) The metal base substrate 50 is provided with an insulating layer 52 between the molded portion 41 and the metal layer 51. Even when a potential difference occurs between the heat sink 43 and the metal layer 51, the electric compressor 10 can be miniaturized by insulating the power element 40 from the metal layer 51 with the insulating layer 52, while ensuring a sufficient creepage distance between the lead 42 and the metal layer 51.

[0092] (3) The metal base substrate 50 is provided with an element-side metal layer 53. The mold-facing portion 521 and the lead-facing portion 522 of the mold portion 41 are located outside the element-side metal layer 53. As a result, in the thickness direction of the metal base substrate 50, a portion of the mold portion 41 faces the element-side metal layer 53, while the other portion of the mold portion 41 faces the insulating layer 52 without passing through the element-side metal layer 53. Therefore, in the metal base substrate 50, heat generated from the power element 40 is transferred to the element-side metal layer 53 via the mold portion 41. In addition, the insulating layer 52 is provided with a mold-facing portion 521 and a lead-facing portion 522, thereby increasing the creepage distance between the lead 42 and the element-side metal layer 53 and the metal layer 51. This allows the power element 40 to dissipate heat from the mold portion 41 to the element-side metal layer 53 while increasing the insulation distance between the metal layer 51 and the element-side metal layer 53 and the lead 42. As a result, the electric compressor 10 can achieve both heat dissipation by the element-side metal layer 53 and securing a sufficient creepage distance between each of the metal layer 51 and the element-side metal layer 53 and the lead 42.

[0093] (4) The power element 40 is attached to the metal base substrate 50 by soldering the heat sink 43 to the element-side metal layer 53. In this case, the inverter 30 is made smaller compared to the case in which the power element 40 is attached to the metal base substrate 50 by, for example, a leaf spring.

[0094] Furthermore, the heat generated from the power element 40 is transferred to the element-side metal layer 53 via the heat sink 43 and solder. In other words, the inverter 30 can improve heat dissipation performance compared to the case where the power element 40 is attached to the metal base substrate 50 by, for example, pressing with a leaf spring.

[0095] (5) The metal base substrate 50 is joined to the power element 40 via an element-side metal layer 53 formed on the insulating layer 52. By providing the element-side metal layer 53, the metal base substrate 50 can prevent damage to the insulating layer 52 caused by conductive foreign matter generated during soldering work, etc.

[0096] (6) The element-side metal layer 53 has an outer mold portion 532 that extends outward from the mold portion 41. By having the outer mold portion 532, the element-side metal layer 53 can increase its heat capacity by the amount of the outer mold portion 532. In other words, the electric compressor 10 can improve the cooling performance of the power element 40 by having the outer mold portion 532 on the element-side metal layer 53.

[0097] (7) The heat generated in the power element 40 is transferred to the main body portion 531 of the element-side metal layer 53, and then to the molded outer portion 532. For example, even if the power element 40 experiences a rapid temperature rise when the electric compressor 10 is started, the element-side metal layer 53 can retain heat through the molded outer portion 532 and dissipate heat to the metal layer 51 via the insulating layer 52. Therefore, even if the power element 40 experiences a rapid temperature rise, the element-side metal layer 53 can suppress heat accumulation by reducing heat absorption relative to heat dissipation. As described above, the metal base substrate 50 can improve the cooling performance of the power element 40 by providing the molded outer portion 532 on the element-side metal layer 53.

[0098] (8) The element-side metal layer 53 is provided with an outer mold projection 533 that extends from the outer mold portion 532. This increases the heat capacity of the element-side metal layer 53 compared to when it does not have an outer mold projection 533. In other words, the electric compressor 10 can improve the cooling performance of the power element 40 compared to when the element-side metal layer 53 does not have an outer mold portion 532.

[0099] (9) The element-side metal layer 53 has molded outer protrusions 533 that are spaced apart from the leads 42 in a plan view of the metal base substrate 50 from the thickness direction. In other words, the metal base substrate 50 can increase the area of ​​the element-side metal layer 53 while ensuring insulation from the leads 42. As a result, the element-side metal layer 53 can improve the cooling performance of the power element 40 while ensuring insulation from the leads 42.

[0100] (10) The inverter 30 is equipped with a temperature sensor 70 provided on the metal base substrate 50. The temperature of the power element 40 is measured by the temperature sensor 70 provided on the metal base substrate 50. For example, compared to the case where the temperature sensor 70 is mounted on the circuit board 31, the temperature sensor 70 can measure the temperature of the power element 40 at a location closer to the power element 40. As a result, the temperature sensor 70 can measure the temperature of the power element 40 with greater accuracy than, for example, when it is mounted on the circuit board 31.

[0101] [Example of changes] The above embodiment can be implemented with the following modifications. The above embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically.

[0102] ○ The temperature sensor 70 may measure the temperature of the power element 40 while being mounted on the circuit board 31. In this case, the inverter 30 does not need to be equipped with a conductive member 54. ○ The element-side metal layer 53 does not necessarily have to have an outer mold projection 533. For example, the element-side metal layer 53 may be a rectangular body consisting of a main body portion 531 and an outer mold portion 532.

[0103] ○ The shape of the outer mold portion 532 is not limited to the embodiment. The outer mold portion 532 may be a part that extends from one of the edges of the main body portion 531. In short, the outer mold portion 532 only needs to extend outward from the mold portion 41.

[0104] ○ The element-side metal layer 53 does not necessarily have to include the mold outer portion 532. For example, the element-side metal layer 53 may consist only of the main body portion 531. ○ The heat sink 43 does not have to be soldered to the element-side metal layer 53. For example, the power element 40 may be pressed by a leaf spring provided on the metal base substrate 50 while the heat sink 43 is in contact with the element-side metal layer 53.

[0105] ○ The metal base substrate 50 may be separate from the element-side metal layer 53. In other words, the metal base substrate 50 may use a plate-shaped metal member placed on the insulating layer 52 as the element-side metal layer 53.

[0106] ○ The metal base substrate 50 does not necessarily have an element-side metal layer 53. In this case, the power element 40 is attached to the metal base substrate 50 with the molded portion 41 facing the insulating layer 52.

[0107] ○ The molded portion 41 does not necessarily have to be equipped with a heat sink 43. In this case, the insulating layer 52 is interposed between the molded portion 41 and the lead 42 and the metal layer 51. ○ The power element 40 is not limited to discrete IGBTs, but may also be a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). Furthermore, for example, the power element 40 may be a modularized power module, or an IGBT in which multiple switching elements S are modularized. Also, the power element 40 may have leads 42 extending from the inside to the outside of the molded portion 41 on multiple sides of the molded portion 41. In this case, the power element 40 has terminal sides 411 equal to the number of such sides.

[0108] ○ The power element 40 may be an IPM including multiple switching elements S. In short, the power element 40 only needs to be configured such that DC power can be converted to AC power by mounting one or more of the power elements 40 on the circuit board 31. For example, the specific configuration of the power element 40, such as the shape and number of leads 42 and the number of switching elements S, can be appropriately changed depending on the type of power element 40 used in the inverter 30.

[0109] ○ When the metal base substrate 50 includes an IPM with an insulating process applied to the molded portion 41 as a power element 40, it may have portions where the insulating layer 52 is not interposed between the molded portion 41 and the metal layer 51. In other words, the insulating layer 52 does not need to have mold-facing portions 521 over the entire portion that overlaps with the molded portion 41 in the thickness direction of the metal base substrate 50. In this case, the insulating layer 52 only needs to extend the mold-facing portions 521 between the molded portion 41 and the metal layer 51 to the extent that the required creepage distance between the lead 42 and the metal layer 51 can be secured.

[0110] In this case, the heat generated in the power element 40 is transferred to the metal layer 51 without passing through the insulating layer 52. As a result, the metal base substrate 50 can improve the cooling performance of the power element 40. ○ The voltage of power supply E is not limited to 800[V]. The insulation distance set between lead 42 and metal layer 51 is appropriately changed according to the voltage of power supply E.

[0111] ○ The electric compressor 10 is not limited to vehicles and can be installed in any location. ○ The electric compressor 10 does not have to be used in the vehicle air conditioning system 100. The electric compressor 10 may be used in other devices. For example, if the vehicle is a fuel cell vehicle equipped with a fuel cell, the electric compressor 10 may be used in a supply device that supplies air to the fuel cell. In this case, the fluid compressed by the compression unit 12 is air. [Explanation of symbols]

[0112] 10...Electric compressor, 12...Compression section, 13...Electric motor, 20...Inverter housing, 30...Inverter, 31...Circuit board, 32...Circuit pattern, 40...Power element, 41...Molded section, 42...Lead, 43...Heat sink, 50...Metal base substrate, 51...Metal layer, 52...Insulating layer, 53...Metal layer on element side, 70...Temperature sensor, 421...First part, 422...Second part, 521...Molded opposing part, 522...Leaded opposing part, 532...Molded outer part, 533...Molded outer protrusion, A...Resin, S...Switching element.

Claims

1. A compression section that compresses the fluid, An electric motor that drives the compression section, An inverter that drives the aforementioned electric motor, The inverter housing comprises the inverter, The aforementioned inverter is A circuit board on which the circuit pattern constituting the inverter circuit is formed, The inverter circuit comprises a molded portion in which the switching elements are molded with resin, and a power element having a plurality of leads exposed from the side of the molded portion and electrically connected to the circuit pattern, Each of the plurality of leads is an electric compressor having a first portion extending outward from the side and a second portion bending from the first portion and extending toward the circuit board, The inverter further comprises a metal base substrate provided between the power element and the inverter housing, The metal base substrate comprises a metal layer that dissipates heat generated from the power element to the inverter housing, and an insulating layer integrally formed on one surface of the metal layer. The power element and the metal base substrate are housed in the inverter housing such that the first portion, the insulating layer, and the metal layer are arranged in this order with respect to the thickness direction of the metal base substrate. The electric compressor is characterized in that the insulating layer comprises a mold-facing portion extending in the thickness direction opposite to the mold portion, and a lead-facing portion extending from the mold-facing portion in the thickness direction opposite to at least the first portion.

2. The molded portion includes a heat sink for dissipating heat from the switching element. The electric compressor according to claim 1, wherein the mold-facing portion is interposed between the heat sink and the metal layer.

3. The metal base substrate further comprises an element-side metal layer provided on the opposite side of the metal layer, with the insulating layer in between. The power element and the metal base substrate are housed in the inverter housing such that the molded portion, the element-side metal layer, the insulating layer, and the metal layer are arranged in this order with respect to the thickness direction. The mold-facing portion is located outside the element-side metal layer and faces the mold portion in the thickness direction. The electric compressor according to claim 1, wherein the lead-facing portion extends outward from the element-side metal layer and faces at least the first portion in the thickness direction from the mold-facing portion.

4. The molded portion includes a heat sink for dissipating heat from the switching element. The electric compressor according to claim 3, wherein the heat sink is soldered to the element-side metal layer.

5. The electric compressor according to claim 3, wherein the element-side metal layer includes an outer mold portion that extends outward from the mold portion in the direction in which the plurality of leads are aligned.

6. The element-side metal layer comprises an outer mold projection that further extends from the outer mold portion in the direction in which the first portion extends, and the outer mold projection that further extends from the outer mold portion in the direction in which the first portion extends, such that it is adjacent to the mold-facing portion and the lead-facing portion in the direction in which the plurality of leads are aligned.

7. The electric compressor according to claim 1, wherein the metal base substrate is provided with a temperature sensor that measures the temperature of the power element and is electrically connected to the circuit board.

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