Electric compressor

Abstract

To provide an electric compressor capable of sufficiently ensuring an insulation distance between connection terminals of a power supply connector that electrically connects an external power supply and an inverter, a power supply connector (9) that electrically connects an external power supply and an inverter (6) in this electric compressor has a plurality of connection terminals (a positive electrode power supply terminal (91), a negative electrode power supply terminal (92), a first interlock terminal (93), and a second interlock terminal (94)), and insulating ribs (95) that are disposed between the connection terminals. In the power supply connector (9), the plurality of connection terminals are electrically connected to a circuit board (63) of the inverter (6) in a state in which the insulating ribs (95) penetrate through the circuit board (63).

Description

Electric compressor

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

[0002] Electric compressors with integrated inverters are known as electric compressors used to compress refrigerants in vehicle air conditioners and the like. An example of this type of electric compressor is described in Patent Document 1. The electric compressor described in Patent Document 1 includes a compression mechanism, an electric motor, an inverter, an inverter housing, and a power connector that electrically connects an external power source to the inverter. The power connector has bus bars (connection terminals) and is fixed to the inverter housing, with the ends of the bus bars (connection terminals) connected to a circuit board of the inverter. The circuit board is provided with a first insulating member that covers the bus bars (connection terminals), and the power connector is provided with a second insulating member that supports and covers the bus bars (connection terminals). The electric compressor described in Patent Document 1 is said to prevent a short circuit from the bus bars (connection terminals) of the power connector to the inverter housing.

[0003] Japanese Patent Application Laid-Open No. 2022-41282

[0004] In the electric compressor described in Patent Document 1, for example, the insulation distance (creepage distance) between bus bars (connection terminals) on the circuit board may not be sufficient. In recent years, electric compressors have become larger in capacity and have higher rated voltages, and it is therefore desirable to ensure a sufficient insulation distance between the connection terminals of the power connector, including the insulation distance on the circuit board.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an electric compressor that can ensure a sufficient insulation distance between the connection terminals of a power connector.

[0006] According to one aspect of the present invention, there is provided a novel electric compressor. The electric compressor includes an electric motor that rotates a rotating shaft, a compression mechanism driven by the rotation of the rotating shaft, an inverter that drives and controls the electric motor, an inverter housing that houses the inverter, and a power connector that is fixed to the inverter housing and electrically connects an external power source to the inverter. The inverter includes a circuit board on which circuit elements are mounted, and the power connector has a plurality of connection terminals and insulating ribs arranged between the connection terminals, and the plurality of connection terminals are electrically connected to the circuit board with the insulating rib penetrating the circuit board.

[0007] According to the present invention, it is possible to provide an electric compressor that can ensure a sufficient insulation distance between the connection terminals of a power connector.

[0008] Fig. 1 is a schematic cross-sectional view of an electric compressor according to an embodiment; Fig. 2 is a front view of a power connector of the electric compressor; Fig. 3 is a perspective view of the power connector of the electric compressor; Fig. 4 is a front view of a main part of a circuit board of an inverter for the electric compressor; Fig. 5 is a perspective view of a main part of a circuit board of an inverter for the electric compressor; Fig. 6 is a front view showing a state in which the power connector is connected to the circuit board; Fig. 7 is a perspective view showing a state in which the power connector is connected to the circuit board.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the terms "first," "second," etc. are used simply to distinguish between similar elements and are not intended to limit the elements to which they are attached.

[0010] 1 is a schematic cross-sectional view of an electric compressor 1 according to an embodiment of the present invention. The electric compressor 1 according to the embodiment is an inverter-integrated electric compressor having an inverter integrated therein. The electric compressor 1 is mounted on a vehicle, for example, to form part of a refrigerant circuit of an air conditioner for the vehicle, and is configured to compress and discharge refrigerant.

[0011] The electric compressor 1 includes a rotating shaft 2 , an electric motor 3 , a compression mechanism 4 , a main body housing 5 , an inverter 6 , an inverter housing 7 , and a cover member 8 .

[0012] The rotating shaft 2 is rotatably supported in a main housing 5 by bearings (not shown). The electric motor 3 is, for example, a three-phase synchronous motor, and is configured to be driven by power supplied from an inverter 6 to rotate the rotating shaft 2. The compression mechanism 4 is configured to be driven by the rotation of the rotating shaft 2 to compress the refrigerant. Although not particularly limited, the compression mechanism 4 may be a scroll compression mechanism. The main housing 5 is made of metal (for example, aluminum die-cast), has a cylindrical cross section, and accommodates the rotating shaft 2, the electric motor 3, and the compression mechanism 4 therein. Within the main housing 5, the electric motor 3 and the compression mechanism 4 are arranged in series.

[0013] The inverter 6 drives and controls the electric motor 3. The inverter housing 7 is integral with the main housing 5 and houses the inverter 6 therein. The inverter housing 7 is provided at the end of the main housing 5 on the electric motor 3 side and has a larger projected area than the main housing 5. The inverter housing 7 is mainly formed by a bottom wall 71 and a peripheral wall 73 rising from the periphery of the bottom wall 71, and has an opening 75 facing the bottom wall 71. The opening 75 of the inverter housing 7 is closed by a cover member 8. The cover member 8 is fixed to the peripheral wall of the inverter housing 7 (which is also part of the main housing 5) with screws or the like (not shown).

[0014] A power connector 9 is fixed to the bottom wall 71 of the inverter housing 7. The power connector 9 supplies DC power from an on-board battery (not shown) serving as an external power source to the inverter 6. The power connector 9 is a so-called HV (high voltage) connector. That is, the power connector 9 electrically connects the on-board battery (external power source) and the inverter 6. A part of the bottom wall 71 of the inverter housing 7 forms a partition wall 77 that separates the inside of the main housing 5 from the inside of the inverter housing 7.

[0015] The main housing 5 is formed with an inlet 5a for allowing the refrigerant to flow into the main housing 5 and an outlet 5b for allowing the refrigerant to flow out of the main housing 5. The inlet 5a is configured to allow the refrigerant to flow into a space between the partition wall 77 and the electric motor 3 inside the main housing 5. The refrigerant that flows into the main housing 5 from the inlet 5a flows along the partition wall 77, passes through the electric motor 3, and reaches the compression mechanism 4, where it is compressed by the compression mechanism 4. The refrigerant compressed by the compression mechanism 4 then flows out from the outlet 5b.

[0016] The refrigerant flowing from the inlet 5 a into the main housing 5 is a low-temperature gas refrigerant. Therefore, the partition wall 77 (the bottom wall 71 of the inverter housing 7) and the electric motor 3 can be cooled by the refrigerant flowing from the inlet 5 a into the main housing 5.

[0017] The inverter 6 will now be described in further detail. The inverter 6 is configured to convert DC power supplied from the vehicle battery via a power connector 9 into three-phase AC power and supply it to the electric motor 3 via, for example, a power supply line 10 extending through a partition wall 77. The inverter 6 includes a plurality of switching elements, specifically six switching elements 61 (only one of which is shown in FIG. 1 ), and a circuit board 63 on which a control circuit 65 for controlling the operation of the six switching elements 61 is mounted. The switching elements 61 are power semiconductor switching elements such as IGBTs and power MOS transistors. In this embodiment, in addition to the control circuit 65, various circuit elements including a capacitor 67 and a coil (not shown) that constitute a noise filter are mounted on the circuit board 63.

[0018] The six switching elements 61 are fixed to an element mounting portion 79 provided in the inverter housing 7 by a press member (not shown). The element mounting portion 79 is formed on the surface of the partition wall 77 facing the inverter housing 7, i.e., on the inner surface of the bottom wall 71 of the inverter housing 7 (the inner bottom surface of the inverter housing 7). Although not particularly limited, the element mounting portion 79 may be a machined surface of the inner surface of the bottom wall 71 of the inverter housing 7 (the inner bottom surface of the inverter housing 7). The element mounting portion 79 functions as a heat dissipation portion that dissipates heat from the six switching elements 61 by using the low-temperature gas refrigerant flowing into the main housing 5. A sheet-like heat dissipation member may be provided between the six switching elements 61 and the element mounting portion 79.

[0019] The circuit board 63 is fixed by screws 13 to the upper surfaces of a plurality of board mounting portions 11 provided inside the inverter housing 7. The board mounting portions 11 are formed to protrude from the inner surface of the bottom wall 71 of the inverter housing 7 (the inner bottom surface of the inverter housing 7). Therefore, in this embodiment, the circuit board 63 is disposed closer to the cover member 8 than the six switching elements 61 inside the inverter housing 7, that is, disposed away from the six switching elements 61 toward the cover member 8 (upward in FIG. 1 ).

[0020] Each of the six switching elements 61 has a lead 61 a extending toward the circuit board 63, or more specifically, a lead 61 a extending through the circuit board 63. These leads 61 a are then, for example, soldered to the circuit board 63, thereby electrically connecting the six switching elements 61 and the circuit board 63.

[0021] Further description will be given of the power connector 9. Figure 2 is a front view of the power connector 9, and Figure 3 is a perspective view of the power connector 9.

[0022] 2 and 3, the power connector 9 has a connector housing 90. The connector housing 90 is made of insulating resin and is formed in a cylindrical shape. A flange portion 90a is formed on one end of the connector housing 90.

[0023] The power connector 9 also has, as connection terminals, a positive power terminal 91 and a negative power terminal 92, which are power terminals, and a pair of interlock terminals (a first interlock terminal 93 and a second interlock terminal 94), which are terminals other than the power terminals. Although a detailed description will be omitted, the interlock terminals (the first interlock terminal 93 and the second interlock terminal 94) are terminals used to detect disconnection of the power connector 9, etc.

[0024] Each of the connection terminals, i.e., the positive power supply terminal 91, the negative power supply terminal 92, the first interlock terminal 93, and the second interlock terminal 94, is formed into a plate shape from metal. The positive power supply terminal 91, the negative power supply terminal 92, the first interlock terminal 93, and the second interlock terminal 94 are integrated with the connector housing 90 by, for example, insert molding. The positive power supply terminal 91, the negative power supply terminal 92, the first interlock terminal 93, and the second interlock terminal 94 each have a protruding portion that protrudes from the end surface on the one end side of the connector housing 90, and are arranged at intervals from one another.

[0025] Furthermore, the power connector 9 has an insulating rib 95, a first surrounding rib 96, and a second surrounding rib 97. The insulating rib 95, the first surrounding rib 96, and the second surrounding rib 97 are formed integrally with the connector housing 90. The insulating rib 95, the first surrounding rib 96, and the second surrounding rib 97 are made of insulating resin, just like the connector housing 90, and are formed to protrude from the end face on the one end side of the connector housing 90.

[0026] The insulating rib 95 is disposed between the connection terminals. The insulating rib 95 is a rib for ensuring insulation between the connection terminals. In this embodiment, the insulating rib 95 has a T-shaped cross section and includes a first portion 95a corresponding to the horizontal bar of the T and located between the power supply terminals (positive power supply terminal 91, negative power supply terminal 92) and the interlock terminals (first interlock terminal 93, second interlock terminal 94), which are terminals other than the power supply terminals, and a second portion 95b corresponding to the vertical bar of the T and located between the positive power supply terminal 91 and the negative power supply terminal 92. The insulating rib 95 is formed to protrude beyond the power supply terminals (positive power supply terminal 91, negative power supply terminal 92) and the interlock terminals (first interlock terminal 93, second interlock terminal 94), which are terminals other than the power supply terminals. In other words, the protruding height (protruding amount) of the insulating rib 95 from the surface on the one end side of the connector housing 90 is greater than the protruding height (protruding amount) of the positive power supply terminal 91, the protruding height (protruding amount) of the negative power supply terminal 92, the protruding height (protruding amount) of the first interlock terminal 93, and the protruding height (protruding amount) of the second interlock terminal 94.

[0027] The first surrounding rib 96 is formed to surround the positive power supply terminal 91. The protruding height (protruding amount) of the first surrounding rib 96 from the surface on the one end side of the connector housing 90 is smaller than the protruding height (protruding amount) of the positive power supply terminal 91.

[0028] The second surrounding rib 97 is formed to surround the negative power supply terminal 92. The protruding height (protruding amount) of the second surrounding rib 97 from the surface on the one end side of the connector housing 90 is smaller than the protruding height (protruding amount) of the negative power supply terminal 92.

[0029] The power connector 9 has a flange portion 90a of the connector housing 90 fixed to the bottom wall 71 of the inverter housing 7 with screws (not shown) so that the connection terminals (positive power terminal 91, negative power terminal 92, first interlock terminal 93, second interlock terminal 94) and ribs (insulating rib 95, first surrounding rib 96, second surrounding rib 97) are positioned inside the inverter housing 7. The power connector 9 fixed to the bottom wall 71 of the inverter housing 7 is also electrically connected to the circuit board 63 of the inverter 6. The electrical connection structure between the power connector 9 and the circuit board 63 of the inverter 6 will be described below.

[0030] First, a description will be given of the circuit board 63 of the inverter 6. Fig. 4 is a front view of the main part of the circuit board 63, and Fig. 5 is a perspective view of the main part of the circuit board 63.

[0031] Referring to Figures 4 and 5, the circuit board 63 is formed with first through holes 631, 631 for the positive power supply terminal 91, second through holes 632, 632 for the negative power supply terminal 92, third through holes 633, 633 for the first interlock terminal 93, and fourth through holes 634, 634 for the second interlock terminal 94.

[0032] The circuit board 63 is also formed with a rib through-hole 635 through which the insulating rib 95 passes. The rib through-hole 635 is formed as a T-shaped hole in a plan view to correspond to the insulating rib 95, which is formed to have a T-shaped cross section. Specifically, the rib through-hole 635 is formed as a hole having a first hole portion 635a corresponding to the horizontal bar of the T, located between the first through-holes 631, 631 and the second through-holes 632, 632 (i.e., through-holes for the power supply terminals) and the third through-holes 633, 633 and the second through-hole 634 (i.e., through-holes for the interlock terminals), and a second hole portion 635b corresponding to the vertical bar of the T, located between the first through-holes 631, 631 (i.e., through-holes for the positive power supply terminal 91) and the second through-holes 632, 632 (i.e., through-holes for the negative power supply terminal 92).

[0033] Furthermore, in this embodiment, two legs of a metal first adapter 81 are soldered to the first through-holes 631, two legs of a metal second adapter 82 are soldered to the second through-holes 632, two legs of a metal third adapter 83 are soldered to the third through-holes 633, and two legs of a metal fourth adapter 84 are soldered to the fourth through-holes 634. The first adapter 81 is configured to removably hold the positive power supply terminal 91, the second adapter 82 is configured to removably hold the negative power supply terminal 92, the third adapter 83 is configured to removably hold the first interlock terminal 93, and the fourth adapter 84 is configured to removably hold the second interlock terminal 94.

[0034] In this embodiment, for such a circuit board 63, the power connector 9 has multiple connection terminals (positive power terminal 91, negative power terminal 92, first interlock terminal 93, second interlock terminal 94) electrically connected to the circuit board 63, with the insulating rib 95 penetrating the circuit board 63.

[0035] FIG. 6 is a front view showing the state in which the power connector 9 is connected to the circuit board 63 of the inverter 6, and FIG. 7 is a perspective view showing the state in which the power connector 9 is connected to the circuit board 63 of the inverter 6.

[0036] Referring to Figures 6 and 7, the insulating rib 95 of the power connector 9 passes through the rib through-hole 635 of the circuit board 63, and the tip side of the insulating rib 95 protrudes from the circuit board 63 (rib through-hole 635).

[0037] The positive power terminal 91 of the power connector 9 is removably attached to a first adapter 81 soldered to first through holes 631, 631 of the circuit board 63, and the negative power terminal 92 of the power connector 9 is removably attached to a second adapter 82 soldered to second through holes 632, 632 of the circuit board 63. In other words, the positive power terminal 91 of the power connector 9 is electrically connected to the first through holes 631, 631 of the circuit board 63 via the first adapter 81, and the negative power terminal 92 of the power connector 9 is electrically connected to the second through holes 632, 632 of the circuit board 63 via the second adapter 82.

[0038] In this embodiment, when the positive power supply terminal 91 is attached to the first adapter 81, the tip side of the first adapter 81 is positioned inside the first surrounding rib 96. In other words, the first surrounding rib 96 is formed so as to surround not only the positive power supply terminal 91 but also the first adapter 81. Similarly, when the negative power supply terminal 92 is attached to the second adapter 82, the tip side of the second adapter 82 is positioned inside the second surrounding rib 97, and the second surrounding rib 97 is formed so as to surround not only the negative power supply terminal 92 but also the second adapter 82.

[0039] The first interlock terminal 93 of the power connector 9 is removably attached to a third adapter 83 soldered to the third through holes 633, 633 of the circuit board 63, and the second interlock terminal 94 of the power connector 9 is removably attached to a fourth adapter 84 soldered to the fourth through holes 634, 634 of the circuit board 63. In other words, the first interlock terminal 93 of the power connector 9 is electrically connected to the third through holes 633, 633 of the circuit board 63 via the third adapter 83, and the second interlock terminal 94 of the power connector 9 is electrically connected to the fourth through holes 634, 634 of the circuit board 63 via the fourth adapter 84.

[0040] According to the electric compressor 1 according to the embodiment, for example, the following effects can be obtained.

[0041] The power connector 9, which electrically connects the external power supply (vehicle battery) and the inverter 6, has a plurality of connection terminals (a positive power supply terminal 91, a negative power supply terminal 92, a first interlock terminal 93, and a second interlock terminal 94) and insulating ribs 95 disposed between the connection terminals. The power connector 9 has a plurality of connection terminals electrically connected to the circuit board 63 of the inverter 6 with the insulating ribs 95 penetrating the circuit board 63.

[0042] Specifically, the circuit board 63 is formed with a plurality of through holes (first through holes 631, 631, second through holes 632, 632, third through holes 633, 633, and fourth through holes 634, 634) to which the plurality of connection terminals of the power connector 9 are electrically connected, and a rib through hole 635 through which the insulating rib 95 of the power connector 9 can pass. The insulating rib 95 of the power connector 9 passes through the rib through hole 635 of the circuit board 63, with the tip side protruding from the circuit board 63 (rib through hole 635), and each of the plurality of connection elements is electrically connected to a corresponding through hole of the circuit board 63.

[0043] In this way, the insulating ribs 95 arranged between the connection terminals of the power connector 9 penetrate the circuit board 63, so that a sufficient insulation distance between the connection terminals of the power connector 9, including the insulation distance on the circuit board 63, can be ensured. Therefore, it is relatively easy to accommodate electric compressors with higher rated voltages. Furthermore, the circuit board 63 is formed with a plurality of through holes to which the connection terminals of the power connector 9 are electrically connected, as well as rib through holes 635 through which the insulating ribs 95 of the power connector 9 penetrate. Therefore, positioning of the power connector 9 when assembling it to the circuit board 63 can be easily performed.

[0044] Each of the multiple connection terminals of the power connector 9 is removably attached to an adapter soldered to a corresponding through-hole in the circuit board 63. Specifically, the positive power terminal 91 is removably attached to a first adapter 81 soldered to first through-holes 631 for the positive power terminal 91, thereby electrically connecting the first through-holes 631. The negative power terminal 92 is removably attached to a second adapter 82 soldered to second through-holes 632 for the negative power terminal 92, thereby electrically connecting the second through-holes 632. Furthermore, the first interlock terminal 93 is removably attached to a third adapter 83 soldered to third through-holes 633 for the first interlock terminal 93, thereby electrically connecting the third through-holes 633. The second interlock terminal 94 is removably mounted to the fourth adapter 84 soldered to the fourth through holes 634, 634 for the second interlock terminal 94, thereby electrically connecting to the fourth through holes 634, 634.

[0045] With this configuration, the power connector 9 can be easily attached to and detached from the circuit board 63, which not only improves the ease of assembly of the power connector 9 but also improves the reusability of the power connector 9.

[0046] In the above embodiment, one circuit board 63 is shown as the circuit board of the inverter 6. However, this is not limited to this, and the inverter 6 may include multiple circuit boards electrically connected to each other. In this case, the power connector 9 is electrically connected to one of the multiple circuit boards.

[0047] In the above-described embodiment, each of the multiple connection terminals of the power connector 9 is removably attached to an adapter soldered to a corresponding through-hole. However, this is not limited to this. Each of the multiple connection elements of the power connector 9 may be directly soldered to a corresponding through-hole. For example, the circuit board 63 may be formed with a first through-hole 631 for the positive power terminal 91, a second through-hole 632 for the negative power terminal 92, a third through-hole 633 for the first interlock terminal 93, and a fourth through-hole 634 for the second interlock terminal 94, and the positive power terminal 91 may be soldered to the first through-hole 631, the negative power terminal 92 may be soldered to the second through-hole 632, the first interlock terminal 93 may be soldered to the third through-hole 633, and the second interlock terminal 94 may be soldered to the fourth through-hole 634.

[0048] Furthermore, in the above-described embodiment, the terminals other than the power supply terminals are a pair of interlock terminals (first interlock terminal 93 and second interlock terminal 94). However, this is not limiting, and the type and number of terminals other than the power supply terminals may be arbitrary.

[0049] 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.

[0050] DESCRIPTION OF SYMBOLS 1...electric compressor, 2...rotating shaft, 3...electric motor, 4...compression mechanism, 5...main body housing, 6...inverter, 7...inverter housing, 8...cover member, 9...power connector, 81...first adapter, 82...second adapter, 83...third adapter, 84...fourth adapter, 91...positive power supply terminal, 92...negative power supply terminal, 93...first interlock terminal, 94...second interlock terminal, 95...insulating rib, 96...first surrounding rib, 97...second surrounding rib, 61...switching element, 61a...lead, 63...circuit board, 631...first through hole, 632...second through hole, 633...third through hole, 634...fourth through hole, 635...rib through hole

Claims

1. An electric compressor having an electric motor that rotates a rotating shaft, a compression mechanism driven by the rotation of the rotating shaft, an inverter that drives and controls the electric motor, an inverter housing that houses the inverter, and a power connector that is fixed to the inverter housing and electrically connects an external power source to the inverter, wherein the inverter includes a circuit board on which circuit elements are mounted, and the power connector has a plurality of connection terminals and insulating ribs arranged between the connection terminals, and the plurality of connection terminals are electrically connected to the circuit board with the insulating rib penetrating the circuit board.

2. The electric compressor as described in claim 1, wherein the circuit board is formed with a plurality of through holes to which the plurality of connection terminals of the power connector are electrically connected, and a rib through hole through which the insulating rib of the power connector passes.

3. The electric compressor according to claim 2, wherein each of said plurality of connection terminals is removably attached to an adapter soldered to a corresponding one of said plurality of through holes.

4. The electric compressor according to claim 2, wherein each of said plurality of connection terminals is soldered to a corresponding one of said plurality of through holes.

5. The electric compressor according to any one of claims 1 to 4, wherein the multiple connection terminals include power supply terminals, i.e., a positive power supply terminal and a negative power supply terminal, and a terminal other than the power supply terminals, the insulating rib protrudes further than the power supply terminal and the terminal other than the power supply terminals, and the insulating rib is formed in a T-shape in cross section and has a portion located between the power supply terminal and the terminal other than the power supply terminal, and a portion located between the positive power supply terminal and the negative power supply terminal.

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