Electric compressor

Abstract

To provide a motor compressor capable of improving assembly workability and electric insulation of a power switching element more than before while ensuring heat dissipation (cooling) of the power switching element.SOLUTION: A motor compressor has a housing which houses an electric motor and a compressing mechanism and an inverter housing part which houses an inverter including a plurality of power transistors Q1 to Q6, which are partitioned off by a partition wall. The inverter housing part has an installation part where the plurality of power switching elements Q1 to Q6 is installed. The power switching elements Q1 to Q6 are united with thermosetting insulation resin IR with at least parts of respective top surfaces 20a and reverse surfaces 20b exposed to constitute a switching element module 30, and the switching element module 30 is installed at the installation part.SELECTED DRAWING: Figure 7

Description

[Technical Field]

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

[0002] Many electric compressors used to compress refrigerant in vehicle air conditioners and the like have an integrated inverter that converts DC power from an on-board battery or the like into AC power and controls the power supply to the electric motor that drives the compression mechanism (driving the electric motor). An example of such an electric compressor is described in Patent Document 1. The electric compressor described in Patent Document 1 has a compression mechanism, an electric motor, and an inverter within a housing, and the interior of the housing is partitioned by a partition wall into a space that houses the compression mechanism and the electric motor and a space that houses the inverter.

[0003] Here, the inverter includes a plurality of power switching elements, and it is required to suppress temperature rise due to heat generation from these power switching elements. In this regard, Patent Document 1 describes a method in which a plurality of power switching elements (power semiconductor elements) are arranged on the inverter side surface of a partition wall, and the plurality of power switching elements are cooled by suction refrigerant through the partition wall. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-275951 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-described configuration, multiple power switching elements had to be disposed one by one on the inverter-side surface of the partition wall, leaving room for improvement in terms of assembly workability, etc. Furthermore, in recent years, the voltage applied to power switching elements has been increasing, leaving room for improvement in terms of ensuring electrical insulation.

[0006] Therefore, an object of the present invention is to provide an electric compressor that can improve the assembly workability and electrical insulation of the power switching elements compared to conventional ones while ensuring the heat dissipation (cooling) properties of the power switching elements. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided an electric compressor. The electric compressor includes an electric motor, a compression mechanism driven by the electric motor to compress a refrigerant, an inverter including a plurality of power switching elements that drives the electric motor, a housing that accommodates the compression mechanism and the electric motor, and an inverter accommodating section that accommodates the inverter, the housing and the inverter accommodating section being separated by a partition wall. In this electric compressor, the inverter accommodating section has an installation section in which the plurality of power switching elements are installed, the installation section being provided on a surface of the partition wall facing the inverter accommodating section. The plurality of power switching elements are integrated with a thermosetting insulating resin to form a switching element module with at least a portion of their upper surfaces and their lower surfaces exposed, and the switching element module is installed in the installation section. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an electric compressor that can improve the assembly workability and electrical insulation of the power switching elements compared to conventional ones while ensuring the heat dissipation (cooling) properties of the power switching elements. [Brief explanation of the drawings]

[0009] [Figure 1]1 is a schematic vertical cross-sectional view of an electric compressor according to an embodiment. [Figure 2] 1 is a view of the electric compressor according to the embodiment with a cover member for the inverter accommodating portion removed, as viewed from the inverter accommodating portion side; [Figure 3] FIG. 2 is a diagram illustrating an example of a circuit configuration of an inverter of the electric compressor according to the embodiment. [Figure 4] FIG. 1 is a diagram illustrating the inside of an inverter accommodating section. [Figure 5] FIG. 2 is a diagram illustrating a power switching element. [Figure 6] FIG. 2 is a diagram illustrating a power switching element. [Figure 7] FIG. 2 is a diagram showing a switching element module. [Figure 8] 10A and 10B are diagrams for explaining installation of a switching element module in an installation portion of an inverter accommodating section. [Figure 9] 10A and 10B are diagrams for explaining installation of a switching element module in an installation portion of an inverter accommodating section. [Figure 10] 10A and 10B are diagrams showing insulating spacers used when installing a switching element module. [Figure 11] 10A and 10B are diagrams for explaining attachment of a circuit board to a board support portion of an inverter accommodating portion. [Figure 12] 10A and 10B are diagrams for explaining attachment of a circuit board to a board support portion of an inverter accommodating portion. [Figure 13] 10A and 10B are diagrams showing a modified example of the switching element module, in which (a) is a perspective view and (b) is a cross-sectional view. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0011] 1 is a schematic longitudinal sectional view of an electric compressor 1 according to one embodiment of the present invention. The electric compressor 1 according to this embodiment is a so-called inverter-integrated electric compressor that has an integrated inverter. The electric compressor 1 may be mounted on a vehicle, for example, to form part of a refrigerant circuit of an automotive air conditioner, and configured to compress and discharge refrigerant.

[0012] Referring to FIG. 1, the electric compressor 1 includes an electric motor 2, a compression mechanism 3 driven by the electric motor to compress a refrigerant, a housing 4 that accommodates the electric motor 2 and the compression mechanism 3, an inverter 5 that drives the electric motor 2, and an inverter accommodating section 6 that accommodates the inverter 5.

[0013] The electric motor 2 is, for example, a three-phase synchronous motor (brushless DC motor). The compression mechanism 3 is, for example, a scroll compression mechanism. The electric motor 2 and the compression mechanism 3 are arranged in series in the axial direction of the output shaft 2a of the electric motor 2 inside a housing 4. The output shaft 2a of the electric motor 2 is connected to the compression mechanism 3 (the orbiting scroll in the case of a scroll compression mechanism).

[0014] The inverter 5 includes various electronic components (described later) and a circuit board 7 on which the various electronic components are mounted. In other words, in this embodiment, the inverter 5 is configured by mounting the various electronic components on the circuit board 7.

[0015] The inverter accommodating portion 6 is provided integrally with the housing 4. The inverter accommodating portion 6 is disposed on one end side of the housing 4 in the axial direction, specifically, on the opposite side of the electric motor 2 from the compression mechanism 3. In this embodiment, the inverter accommodating portion 6 includes an accommodating portion main body 61 formed integrally with the housing 4, and a cover member 62 that is removable from the accommodating portion main body 61.

[0016] The accommodating section main body 61 has a bottom wall 611 and a peripheral wall 612 that rises from the periphery of the bottom wall 611 and defines an opening that faces the bottom wall 611. The cover member 62 is attached to the accommodating section main body 61 to close the opening. A part of the bottom wall 611 of the accommodating section main body 61 (which is also the bottom wall of the inverter accommodating section 6) forms a partition wall 8 that separates the interior of the housing 4 from the interior of the inverter accommodating section 6. The power supply line 9 from the inverter 5 to the electric motor 2 extends through the partition wall 8 in an airtight and liquidtight manner.

[0017] Fig. 2 is a view of the electric compressor 1 viewed from the inverter accommodating section 6 side with the cover member 62 of the inverter accommodating section 6 removed. As shown in Fig. 2, the circuit board 7 that constitutes the inverter 5 is attached inside the inverter accommodating section 6 (accommodating section main body 61) with a plurality of first fixing bolts 11 (fixing members).

[0018] Returning to Fig. 1, a refrigerant inlet 4a is formed in a portion of the housing 4 on the partition wall 8 side, allowing refrigerant from the outside to flow into the housing 4. The refrigerant that has flowed into the housing 4 flows inside the housing 4 (through the gap in the electric motor 2) and reaches the compression mechanism 3, which is driven by the electric motor 2 to compress and discharge the refrigerant.

[0019] The refrigerant flowing into the housing 4 is, for example, a refrigerant that has passed through an expansion valve and an evaporator in the refrigerant circuit of the vehicle air conditioning system, and is a low-temperature, low-pressure refrigerant. Therefore, the partition wall 8 and the electric motor 2 can be cooled by the refrigerant flowing into the housing 4 from the refrigerant inlet 4a. The refrigerant flowing inside the housing 4 is compressed by the compression mechanism 3 to become a high-temperature, high-pressure refrigerant, and is then discharged from the compression mechanism 3. The (high-temperature, high-pressure) refrigerant discharged from the compression mechanism 3 then flows out from the refrigerant outlet 4b formed in the housing 4.

[0020] Here, a brief description will be given of the inverter 5. Fig. 3 is a diagram showing an example of the circuit configuration of the inverter 5. In this embodiment, the inverter 5 is configured to convert DC power from an external power supply (for example, an in-vehicle battery) VB into three-phase AC power and supply it to the electric motor 2.

[0021] 3, the inverter 5 includes a smoothing capacitor 51, a switching unit 52, a control circuit 53, and a noise filter 54. As described above, these components are mounted on the circuit board 7 to form the inverter 5.

[0022] Smoothing capacitor 51 is connected between the power supply line of external power supply VB and the ground line, and smoothes the DC voltage from external power supply VB.

[0023] The switching unit 52 includes six power switching elements Q1 to Q6 and six diodes D1 to D6. Although not particularly limited, the power switching elements Q1 to Q6 may be IGBTs (insulated gate bipolar transistors). The switching unit 52 is configured to control (PMW control) the power switching elements Q1 to Q6, thereby converting the DC voltage from the external power supply VB, which has been smoothed by the smoothing capacitor 51, into a three-phase AC voltage and supplying it to the electric motor 2.

[0024] To further explain switching unit 52, switching unit 52 has a U-phase arm, a V-phase arm, and a W-phase arm that are provided in parallel with one another between the power supply line of external power supply VB and the ground line.

[0025] The U-phase arm has two power switching elements Q1 and Q2 connected in series, with diodes D1 and D2 connected in anti-parallel to each of the power switching elements Q1 and Q2. The V-phase arm has two power switching elements Q3 and Q4 connected in series, with diodes D3 and D4 connected in anti-parallel to each of the power switching elements Q3 and Q4. The W-phase arm has two power switching elements Q5 and Q6 connected in series, with diodes D5 and D6 connected in anti-parallel to each of the power switching elements Q5 and Q6.

[0026] Furthermore, the midpoints of the U-, V-, and W-phase arms are connected at one end to the other end of the star-connected U-, V-, and W-phase coils of the electric motor 2. That is, the midpoints of power switching elements Q1 and Q2 of the U-phase arm are connected to the U-phase coil, the midpoints of power switching elements Q3 and Q4 of the V-phase arm are connected to the V-phase coil, and the midpoints of power switching elements Q5 and Q6 of the W-phase arm are connected to the W-phase coil.

[0027] By controlling the ratio between the ON period of the power switching element on the power line side of each phase arm and the ON period of the power switching element on the ground line side, i.e., by PWM controlling the multiple power switching elements Q1 to Q6, the switching unit 52 can convert the DC power from the external power source VB smoothed by the smoothing capacitor 51 into three-phase AC power and supply it to the electric motor 2, thereby driving the electric motor 2.

[0028] The control circuit 53 controls (PWM control) the power switching elements Q1 to Q6 to drive the electric motor 2 and thus the compression mechanism 3 based on a control signal from outside (for example, the control device of the above-mentioned vehicle air conditioner).

[0029] The noise filter 54 includes a capacitor and a coil (inductor), which are not shown. Although not particularly limited, in this embodiment, the noise filter 54 is provided between the smoothing capacitor 51 and the switching unit 52, and mainly suppresses ripple noise and EMI / EMC noise caused by the operation of the power switching elements Q1 to Q6.

[0030] Next, a description will be given of the accommodation structure of the inverter 5 in this embodiment. As described above, in this embodiment, the inverter 5 is accommodated in the inverter accommodating portion 6.

[0031] [Inverter housing section 6] 4 is a diagram showing the inside of the inverter accommodating section 6 (without the inverter 5). As described above, the inverter accommodating section 6 includes an accommodating section main body 61 and a cover member 62. In this embodiment, the inverter accommodating section 6 also includes an installation section 63 on which the power switching elements Q1 to Q6 are installed, and a board support section 64 that supports the circuit board 7 that constitutes the inverter 5.

[0032] The installation section 63 is provided on the inner bottom surface of the accommodating section main body 61, i.e., on the surface of the partition wall 8 facing the inverter accommodating section 6. The installation section 63 only needs to be provided on the surface of the partition wall 8 facing the inverter accommodating section 6, and may be formed as a convex portion on the surface of the partition wall 8 facing the inverter accommodating section 6, or as a concave portion on the surface of the partition wall 8 facing the inverter accommodating section 6, or may be formed by placing a separate member on the surface of the partition wall 8 facing the inverter accommodating section 6.

[0033] 4, the installation portion 63 is formed with bolt holes 631, the same number as the number of power switching elements Q1 to Q6 (i.e., six), into which second fixing bolts 12 (see FIG. 5) as fixing members for fixing each of the power switching elements Q1 to Q6 are screwed, and countersunk portions 632 are formed around each bolt hole 631. Most of the installation portion 63 is formed as a flat surface, except for the bolt holes 631 and countersunk portions 632. Note that countersunk portions 632 accommodate flange portions 412 of the insulating spacer 41, which will be described later.

[0034] The board support portion 64 is configured to support the circuit board 7 at a position farther from the partition wall 8 (the surface of the partition wall 8 facing the inverter accommodating portion 6) than the installation portion 63. That is, within the inverter accommodating portion 6, the circuit board 7 is disposed at a position closer to the cover member 62 than the power switching elements Q1 to Q6. In other words, when the cover member 62 side is the upper side and the partition wall 8 side is the lower side, the circuit board 7 is disposed above the power switching elements Q1 to Q6. In this embodiment, the board support portion 64 includes a plurality of protrusions 641 that protrude from the inner bottom surface of the accommodating portion main body 61, i.e., the surface of the partition wall 8 facing the inverter accommodating portion 6, and a bolt hole into which the above-mentioned first fixing bolt 11 (see FIG. 2) is screwed is formed on the upper surface of each of the plurality of protrusions 641.

[0035] [Power switching elements Q1 to Q6 and switching element module] 5 and 6 are diagrams showing power switching elements. In this embodiment, each of the power switching elements Q1 to Q6 has an insertion hole (hereinafter referred to as a "first insertion hole") 21 through which a second fixing bolt 12 for fixing the element is inserted. The first insertion hole 21 passes through the power switching element from the upper surface 20a to the lower surface 20b. The second fixing bolt 12 is usually conductive.

[0036] Each of the power switching elements Q1 to Q6 has three terminals 22. In this embodiment, the three terminals 22 extend laterally from one side surface of the power switching element and are bent midway so that their tips point upward.

[0037] Each of the power switching elements Q1 to Q6 has a die pad 23. Parts of the die pad 23 (specifically, parts of both sides) are exposed to both sides of the power switching element.

[0038] Furthermore, as shown in FIG. 6, in this embodiment, a part of the die pad 23 (specifically, the lower surface) is exposed on the lower surface 20b of each of the power switches Q1 to Q6.

[0039] The die pad 23 is capable of dissipating heat generated by the power switching element, and is made of, for example, a metal having thermal conductivity and electrical conductivity.

[0040] 7, the power switching elements Q1 to Q6 are hardened, that is, integrated, with a thermosetting insulating resin IR such as epoxy resin (hereinafter simply referred to as "insulating resin") to form the switching element module 30. Therefore, in this embodiment, the switching element module 30 is installed in the installation section 63 of the inverter accommodating section 6.

[0041] Specifically, the power switching elements Q1 to Q6 are integrated with (solidified with) insulating resin IR with their respective upper and lower surfaces 20a and 20b exposed and spaced apart from each other to form the switching element module 30. In other words, in the switching element module 30, most of all side surfaces of each of the power switching elements Q1 to Q6 and the base end portions of the three terminals 22 are covered with insulating resin IR.

[0042] Furthermore, in the switching element module 30, the exposed bottom surfaces 20b of the power switching elements Q1 to Q6 are flush with the bottom surface of the insulating resin IR surrounding them. That is, the bottom surface of the switching element module 30 is flat as a whole.

[0043] In this embodiment, the power switching elements Q1 to Q6 are arranged in two rows in the switching element module 30. That is, the power switching elements Q1, Q3, and Q5 are arranged on one side of the switching element module 30, and the power switching elements Q2, Q4, and Q6 are arranged on the other side of the switching element module 30. However, this is not limiting, and the arrangement of the power switching elements Q1 to Q6 in the switching element module 30 can be set as desired.

[0044] In this embodiment, most of the side surfaces of each of the power switching elements Q1 to Q6 in the switching element module 30 are covered with insulating resin IR. However, this is not limited to this. It is sufficient that at least the exposed portion of the die pad 23 on the side of each of the power switching elements Q1 to Q6 and the base end portion of the terminal 22 are covered with insulating resin IR, and the extent of the side surfaces of the power switching elements that are covered with insulating resin IR can be set as desired.

[0045] [Installation of the switching element module 30] 8 and 9 are diagrams for explaining the installation of the switching element module 30 on the installation section 63 of the inverter accommodating section 6. In this embodiment, the switching element module 30 is placed on the installation section 63 of the inverter accommodating section 6 via the same number of insulating spacers 41 as the number of power switching elements Q1 to Q6 (i.e., six) and two insulating sheets 42, and is fixed to the installation section 63 by the same number of second fixing bolts 12 as the number of power switching elements Q1 to Q6.

[0046] The insulating spacer 41 is formed of, for example, insulating resin, and as shown in FIG. 10 , has a cylindrical portion (insulating cylindrical portion) 411 and a flange portion (insulating flange portion) 412 provided on one end side of the cylindrical portion 411. The cylindrical portion 411 is insertable into the first insertion holes 21 of the power switching elements Q1 to Q6; that is, it has a smaller diameter than the first insertion holes 21 and a length equivalent to, or preferably slightly shorter than, the length of the first insertion holes 21. The second fixing bolt 12 can be inserted into the inside of the cylindrical portion 411. The flange portion 412 is receivable in a counterbore portion 632 formed in the installation portion 63 of the inverter accommodating portion 6; that is, it has a smaller diameter than the counterbore portion 632 and a thickness equivalent to, or preferably slightly smaller than, the depth of the counterbore portion 632.

[0047] The insulating sheet 42 is made of a material having heat dissipation and insulating properties, and is large enough to cover the lower surfaces 20b of the power switching elements Q1, Q3, and Q5 (or Q2, Q4, and Q6) in the switching element module 30. The insulating sheet 42 also has through holes 421 formed in positions corresponding to the first insertion holes 21 of the power switching elements Q1, Q3, and Q5 (or Q2, Q4, and Q6) in the switching element module 30, through which the cylindrical portions 411 of the insulating spacer 41 can be inserted.

[0048] The switching element module 30 is installed, for example, in the following procedure.

[0049] First, the flange portions 412 of the six insulating spacers 41 are placed in the six countersunk portions 632 formed in the installation portion 63 of the inverter accommodating portion 6. Therefore, the cylindrical portion 411 (i.e., the insulating cylindrical portion) of each insulating spacer 41 protrudes from (the surface of) the installation portion 63.

[0050] Next, the two insulating sheets are placed on the installation portion 63. At this time, the cylindrical portion 411 of the insulating spacer 41 arranged in the counterbore portion 632 is inserted into the through hole 421 of the insulating sheet .

[0051] Next, the switching element module 30 is placed on the two insulating sheets 42. At this time, the cylindrical portion 411 of the insulating spacer 41 arranged in the counterbore portion 632 is inserted into the first insertion hole 21 of the power switching element of the switching element module 30.

[0052] As a result, the switching element module 30 is placed on the installation section 63 of the inverter accommodating section 6 via the same number of insulating spacers 41 as the power switching elements Q1 to Q6 and two insulating sheets 42. More specifically, the switching element module 30 is placed on the installation section 63 via the two insulating sheets 42 in a state where the cylindrical portions 411 (i.e., insulating cylindrical portions) of the insulating spacers 41 are inserted into the first insertion holes 21 of each of the power switching elements Q1 to Q6.

[0053] Although two insulating sheets 42 are used here, they may be integrated into one insulating sheet.

[0054] Thereafter, the switching element module 30 is fixed to the installation portion 63 by the same number of second fixing bolts 12 as the number of power switching elements Q1 to Q6. Specifically, the switching element module 30 is fixed to the installation portion 63 by threading the second fixing bolts 12, which are inserted into the cylindrical portions 411 (insulating cylindrical portions) of the insulating spacers 41 inserted into the first insertion holes 21 of each of the power switching elements Q1 to Q6, into bolt holes 631 formed in the installation portion 63 (see FIG. 9).

[0055] [Attaching the circuit board 7 to the board support portion 64] 11 and 12 are diagrams for explaining the attachment of the circuit board 7 to the board support portion 64 of the inverter accommodating portion 6. In this embodiment, the circuit board 7 is attached to the board support portion 64 after the switching element module 30 is installed (fixed) in the installation portion 63.

[0056] In this embodiment, the circuit board 7 is pre-mounted with electronic components other than the power switching elements Q1 to Q6 that constitute the inverter 5. Specifically, in this embodiment, a smoothing capacitor 51, diodes D1 to D6, a control circuit 53, and a noise filter 54 are pre-mounted as the other electronic components on the other surface of the circuit board 7 opposite to one surface (hereinafter referred to as the "partition-wall-side surface") of the circuit board 7 that faces the partition wall 8 when the circuit board 7 is attached to the board support part 64. However, in FIGS. 11 and 12, the diodes D1 to D6 are omitted, and the smoothing capacitor 51 and the noise filter 54 are housed in a filter case 55 and mold-sealed with a thermosetting insulating resin, and are mounted on the circuit board 7 in a state where they are integrated with the filter case 55.

[0057] The circuit board 7 is also formed with terminal holes 71 into which the terminals 22 of the power switching elements Q1 to Q6 are connected (inserted). The circuit board 7 is further formed with a plurality of insertion holes (hereinafter referred to as "second insertion holes") 72, each of which can receive a first fixing bolt 11. The second insertion holes 72 are arranged to correspond to the protrusions 641 that form the board support portion 64.

[0058] 12, the circuit board 7 is placed on the board support section 64 (i.e., the upper surface of the plurality of protrusions 641) of the inverter accommodating section 6 with the other surface on which the other electronic components are mounted facing up. At this time, the plurality of second insertion holes 72 of the circuit board 7 are positioned over bolt holes formed in the upper surfaces of the plurality of protrusions 641, and the terminals 22 of the power switching elements Q1 to Q6 are inserted into the terminal holes 71 of the circuit board 7 with their tips protruding from the other surface of the circuit board 7 (the surface opposite to the surface on the partition wall side).

[0059] Thereafter, the circuit board 7 placed on the board support portion 64 (on the upper surfaces of the plurality of protrusions 641) is fixed to the board support portion 64 by the plurality of first fixing bolts 11. Specifically, the plurality of first fixing bolts 11 inserted through the plurality of second insertion holes 72 are screwed into bolt holes formed on the upper surfaces of the plurality of protrusions 641, thereby fixing the circuit board 7 to the board support portion 64. At this time, the filter case 55 is also fastened to the board support portion 64 by some of the first fixing bolts 11 (see FIG. 2). In addition, the tip portions of the terminals 22 of the power switching elements Q1 to Q6 are soldered to the circuit board 7, thereby electrically connecting the power switching elements Q1 to Q6 to the circuit board 7.

[0060] Although detailed description is omitted, the power supply line 9 (or its terminal portion) is also inserted into an insertion hole formed in the circuit board 7, with its tip portion protruding from the other surface of the circuit board 7, and is electrically connected to the circuit board 7 by a connecting member or the like (not shown). Furthermore, when the circuit board 7 is placed on the board support portion 64, it is electrically connected to the external power source VB via the connector 13.

[0061] [Installation of cover member 62] After the circuit board 7 is attached to the board support portion 64 and the above-mentioned electrical connections are made, the cover member 62 is attached to the accommodating portion main body 61 via fastening bolts (not shown) or the like. This allows the inverter 5 to be accommodated in the inverter accommodating portion 6. Note that within the inverter accommodating portion 6, the other surface of the circuit board 7 (the surface opposite to the surface on the partition wall side) faces the cover member 62 and can also be referred to as the "cover member side surface." In other words, in this embodiment, the switching element module 30 (power switching elements Q1 to Q6) is provided on the surface of the circuit board 7 on the partition wall side, and the smoothing capacitor 51, noise filter 54, etc. are provided on the surface of the circuit board 7 on the cover member side.

[0062] The electric compressor 1 according to this embodiment provides the following advantages.

[0063] The power switching elements Q1 to Q6 are integrated with insulating resin IR with their respective upper and lower surfaces exposed to form a switching element module 30, and this switching element module 30 is installed in a mounting section 63 of the inverter accommodating section 6. This allows the power switching elements Q1 to Q6 to be installed in one go, improving the ease of assembling the power switching elements compared to conventional methods. Furthermore, because each of the power switching elements Q1 to Q6 is surrounded by insulating resin IR, the electrical insulation of the power switching elements is also improved compared to conventional methods. Furthermore, the mounting section 63 is provided on the surface of a partition wall 8 separating the interior of the housing 4 from the interior of the inverter accommodating section 6, facing the inverter accommodating section 6. The partition wall 8 is cooled by the refrigerant (low-temperature, low-pressure refrigerant) flowing into the housing 4. This ensures heat dissipation (cooling) of the power switching elements Q1 to Q6.

[0064] In addition to the installation section 63, the inverter accommodating section 6 has a board support section 64 configured to support the circuit board 7 constituting the inverter 5 at a position farther from the partition wall 8 than the installation section 63. In other words, when the cover member 62 side of the inverter accommodating section 6 is the upper side and the partition wall 8 side is the lower side, the circuit board 7 can be supported above the power switching elements Q1 to Q6. This reduces the impact of heat generated by the power switching elements Q1 to Q6 on the circuit board 7, while also reducing the area occupied by the inverter 5. This prevents the inverter accommodating section 6, and therefore the electric compressor 1, from becoming larger.

[0065] In the switching element module 30, the base end side portions of the terminals 22 of the power switching elements Q1 to Q6 are covered with insulating resin IR, which reinforces the terminals 22 of the power switching elements Q1 to Q6, improving the earthquake resistance of the power switching elements Q1 to Q6.

[0066] In the switching element module 30, the exposed portions of the die pad 23 on each side of the power switching elements Q1 to Q6 are covered with insulating resin IR. Therefore, even if the voltage applied to the power switching elements increases, the power switching elements can be stably fixed to the installation portion 63 using a (conductive) fixing member. This improves the vibration resistance of the power switching elements Q1 to Q6.

[0067] In the switching element module 30, the lower surface 20b of each of the power switching elements Q1 to Q6 is flush with the lower surface of the insulating resin IR. This allows the switching element module 30 to be stably installed on the installation portion 63, and also allows for effective heat dissipation (cooling) of the power switching elements Q1 to Q6 by using the die pad 23, part of which (lower surface) is exposed on the lower surfaces 20b of the power switching elements Q1 to Q6.

[0068] The switching element module 30 is placed on a mounting portion 63 via an insulating sheet 42 with the cylindrical portions 411 (insulating cylindrical portions) of the insulating spacers 41 inserted into the first insertion holes 21 of the power switching elements Q1 to Q6, and is fixed to the mounting portion 63 with second fixing bolts 12 inserted into the cylindrical portions 411 (insulating cylindrical portions). A portion (lower surface) of the die pad 23 is exposed on the lower surface 20b of each of the power switching elements Q1 to Q6. This makes it possible to adequately handle even high voltages applied to the power switching elements, and the power switching elements Q1 to Q6 can achieve high heat dissipation (cooling) properties, high electrical insulation, and high earthquake resistance.

[0069] In the above-described embodiment, the entire top surface 20a of each of the power switching elements Q1 to Q6 in the switching element module 30 is exposed. However, this is not limited to this. It is sufficient that at least the first insertion hole 21 and its surroundings are exposed on the top surface 20a of each of the power switching elements Q1 to Q6, and other parts of the top surface 20a may be covered with insulating resin IR. In other words, it is sufficient that at least a portion of the top surface 20a of each of the power switching elements Q1 to Q6 is exposed.

[0070] 13(a) and 13(b), the six power switching elements Q1 to Q6 may be divided into two, forming two switching element modules 30' each including three power switching elements. In this case, in each switching element module 30', the side surfaces, the portions of the base ends of the terminals 22, and at least a portion of the top surface (any portion excluding the first insertion holes 21 and their surroundings) of the three power switching elements Q1, Q3, and Q5 (or Q2, Q4, and Q6) are individually covered with insulating resin IR.

[0071] Adjacent power switching elements, for example, Q1 and Q3 or Q4 and Q6, are connected by connecting portions 31 formed by insulating resin IR in a deformable manner, thereby integrating them into a switching element module 30'. The connecting portions 31 are configured to deform when a force equal to or greater than a predetermined value is applied, thereby expanding or contracting the spacing between adjacent switching element modules. The shape and number of connecting portions 31 can be set as desired.

[0072] In this way, when installing the switching element module 30' on the installation section 63, it is possible to easily align, for example, the first insertion holes 21 of the power switching elements with the bolt holes 631 formed in the installation section 63. Therefore, even if there is variation in the switching element modules 30', for example, the switching element modules 30' can be easily and reliably installed on the installation section 63, further improving the ease of assembly.

[0073] The above describes the embodiments of the present invention and their modifications. However, the present invention is not limited to the above-described embodiments and modifications, and it goes without saying that further modifications are possible based on the technical concept of the present invention. [Explanation of symbols]

[0074] 1...electric compressor, 2...electric motor, 3...compression mechanism, 4...housing, 5...inverter, 6...inverter accommodating section, 7...circuit board, 8...partition wall, 21...first insertion hole, 22...terminal, 23...die pad, 30, 30'...switching element module, 31...connecting section, 41...insulating spacer, 411...cylindrical section (insulating cylindrical section), 42...insulating sheet, 61...accommodating section main body, 62...cover member, 63...installation section, 64...substrate support section, IR...insulating resin, Q1 to Q6...power switching elements

Claims

1. An electric compressor including an electric motor, a compression mechanism driven by the electric motor to compress a refrigerant, an inverter including a plurality of power switching elements that drive the electric motor, a housing that accommodates the compression mechanism and the electric motor, and an inverter accommodating section that accommodates the inverter, wherein an interior of the housing and an interior of the inverter accommodating section are separated by a partition wall, the inverter accommodating section has an installation section in which the plurality of power switching elements are installed, the installation section being provided on a surface of the partition wall facing the inverter accommodating section, the plurality of power switching elements are integrated with a thermosetting insulating resin in a state in which at least a part of an upper surface and a lower surface of each of the power switching elements are exposed, thereby constituting a switching element module, and the switching element module is installed on the installation section. Electric compressor.

2. 2. The electric compressor according to claim 1, wherein the inverter accommodating portion further includes a board support portion that supports a circuit board constituting the inverter, the board support portion being configured to support the circuit board at a position farther from the partition wall than the installation portion.

3. each of the plurality of power switching elements has an insertion hole through which a fixing member for fixing the power switching element to the installation portion can be inserted, the insertion hole penetrating from an upper surface to a lower surface; In the switching element module, the insertion hole and its surroundings are exposed on the upper surface of each of the plurality of power switching elements, and a base end side portion of each terminal of the plurality of power switching elements is covered with the insulating resin. The electric compressor according to claim 1 or 2.

4. a portion of a die pad is exposed on a side of each of the plurality of power switching elements; In the switching element module, exposed portions of the die pad on the sides of each of the plurality of power switching elements are covered with the insulating resin. The electric compressor according to any one of claims 1 to 3.

5. 5. The electric compressor according to claim 1, wherein in the switching element module, a lower surface of each of the plurality of power switching elements is flush with a lower surface of the insulating resin.

6. each of the plurality of power switching elements has an insertion hole through which a conductive fixing member for fixing the power switching element to the installation portion is inserted, the insertion hole penetrating from an upper surface to a lower surface; a die pad is partially exposed on a lower surface of each of the plurality of power switching elements; the switching element module is mounted on the installation part with insulating cylindrical parts inserted into the insertion holes of the plurality of power switching elements and with an insulating sheet interposed between them, and is fixed to the installation part by the conductive fixing members inserted into the inside of the insulating cylindrical parts. The electric compressor according to any one of claims 1 to 5.

7. 7. The electric compressor according to claim 1, wherein in the switching element module, each of the plurality of power switching elements is individually covered with the insulating resin on a part of an upper surface, a side surface, and a portion on a base end side of a terminal, and two adjacent power switching elements are connected via a connecting portion formed in a deformable manner by the insulating resin.

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