Electric compressor
By using a press-fit component with good thermal conductivity to fix the switching element inside the inverter housing, the problem of high temperature of the switching element caused by the large capacity of electric compressors is solved, and a highly efficient cooling effect is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SANDEN CO LTD
- Filing Date
- 2024-11-12
- Publication Date
- 2026-07-10
AI Technical Summary
With the increasing capacity and rated power of electric compressors, the temperature of switching elements is rising, requiring improved cooling performance to cope with the trend of high temperature.
A pressing component with good thermal conductivity is used to fix the switching element in the component mounting section inside the inverter housing. The configuration between the pressing component and the circuit board achieves stable fixation and heat dissipation of the switching element.
The cooling performance of the switching elements has been improved, achieving efficient heat dissipation and stable operation.
Smart Images
Figure CN122374548A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to electric compressors. Background Technology
[0002] Electric compressors used for compressing refrigerant in vehicle air conditioning systems and the like are known to have an integrated inverter. In such electric compressors, the inverter includes multiple switching elements (IGBTs and power MOS transistors, etc.), which are respectively fixed to designated locations by threads. Existing technical documents Patent documents
[0003] Patent Document 1: Japanese Patent Application Publication No. 2003-322082 Patent Document 2: Japanese Patent Application Publication No. 2020-198713 Summary of the Invention The problem to be solved by the present invention
[0004] In recent years, due to the increasing capacity of electric compressors and the accompanying rise in rated power, the voltage input to switching elements is becoming higher. Therefore, the temperature of switching elements tends to rise further, requiring corresponding measures.
[0005] Therefore, the object of the present invention is to provide an electric compressor that can achieve higher cooling performance for switching elements compared with the past. Methods for solving problems
[0006] According to one aspect of the present invention, a novel electric compressor is provided. The provided electric compressor comprises: an electric motor for rotating a rotating shaft; a compression mechanism driven by the rotation of the rotating shaft; and an inverter for driving and controlling the electric motor, the inverter being housed in an inverter housing. The inverter includes a plurality of switching elements, the plurality of switching elements being fixed to an element mounting portion disposed within the inverter housing by a pressing member. The pressing member comprises: a plurality of fixing portions fixed to a mounting portion disposed within the inverter housing; and a plurality of pressing portions for pressing any one of the plurality of switching elements onto the element mounting portion, the pressing member being formed of a thermally conductive material. Invention Effects
[0007] According to the present invention, an electric compressor that can achieve higher cooling performance for switching elements compared to conventional methods can be provided. Attached Figure Description
[0008] Figure 1 This is a schematic cross-sectional view of the electric compressor in the embodiment. Figure 2This is a front view of the fixed structure of the switching element of the electric compressor. Figure 3 This is a top view of the fixed structure of the switching element of the electric compressor. Figure 4 This is an exploded perspective view of the fixed structure of the switching element of the electric compressor. Figure 5 This is a top view of the other fixed structures of the switching element of the electric compressor. Detailed Implementation
[0009] Figure 1 This is a schematic cross-sectional view of an electric compressor 1 according to one embodiment of the present invention. The electric compressor 1 of this embodiment is an inverter-integrated electric compressor with an inverter integrally assembled within it. The electric compressor 1 is, for example, mounted in a vehicle and forms part of the refrigerant circuit of a vehicle air conditioning system, configured to compress and discharge refrigerant.
[0010] The electric compressor 1 has a rotating shaft 2, an electric motor 3, a compression mechanism 4, a main housing 5, an inverter 6, an inverter housing 7, and a cover component 8.
[0011] The rotating shaft 2 is rotatably supported on the main housing 5 via bearings (not shown). The electric motor 3, for example a three-phase synchronous motor, is configured to be driven by power supplied from the inverter 6, causing the rotating shaft 2 to rotate. The compression mechanism 4 is configured to be driven by the rotation of the rotating shaft 2, compressing the refrigerant. Although not particularly limited, the compression mechanism 4 can be a scroll compressor. The main housing 5 is made of metal (e.g., die-cast aluminum) and has a cylindrical cross-section, housing the rotating shaft 2, the electric motor 3, and the compression mechanism 4. Inside the main housing 5, the electric motor 3 and the compression mechanism 4 are arranged in series.
[0012] The inverter 6 drives and controls the electric motor 3. The inverter housing 7 is integrally formed with the main housing 5, housing the inverter 6 internally. In this embodiment, the inverter housing 7 is located at the end of the main housing 5 on the side of the electric motor 3, 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 opposite to 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) by screws (not shown in the figure).
[0013] A power connector (HV connector) 9 for supplying DC power from an external power source, such as a vehicle battery (not shown), to the inverter 6 is fixed to the bottom wall 71 of the inverter housing 7. That is, the power connector 9 electrically connects the vehicle battery (external power source) to the inverter 6. Additionally, a portion of the bottom wall 71 of the inverter housing 7 forms a partition 77 that separates the interior of the main housing 5 from the interior of the inverter housing 7.
[0014] The main housing 5 has an inlet 5a for refrigerant to flow into the main housing 5 and an outlet 5b for refrigerant to flow out of the main housing 5. The inlet 5a is configured between a partition wall 77 that allows refrigerant to flow into the main housing 5 and an electric motor 3. The refrigerant flowing into the main housing 5 from the inlet 5a flows along the partition wall 77, reaches the compression mechanism 4 via the electric motor 3, and is compressed by the compression mechanism 4. Then, the refrigerant compressed by the compression mechanism 4 flows out from the outlet 5b.
[0015] The refrigerant flowing into the main housing 5 from the inlet 5a is a low-temperature gaseous refrigerant. Therefore, the refrigerant flowing into the main housing 5 from the inlet 5a can cool the partition wall 77 (the bottom wall 71 of the inverter housing 7) and the electric motor 3.
[0016] Inverter 6 will be further described. Inverter 6 is configured to convert DC power supplied from the vehicle battery via power connector 9 into three-phase AC power, for example, supplied to the electric motor 3 via power line 10 extending through partition 77. Inverter 6 includes: a plurality of switching elements, specifically six switching elements 61 (in... Figure 1 (Only one of them is shown in the diagram). A circuit board 63 is also provided, on which a control circuit 65 is mounted to control the operation of six switching elements 61. The switching elements 61 are power semiconductor switching elements such as IGBTs and power MOS transistors. Furthermore, in this embodiment, in addition to the control circuit 65, various circuit elements, including capacitors 67 constituting a noise filter and coils (not shown), are also mounted on the circuit board 63.
[0017] Six switching elements 61 are fixed to an element mounting section 79 disposed within the inverter housing 7 by a pressing member 20 (described later). The element mounting section 79 is formed on the side of the partition wall 77 on the inverter housing 7 side, that is, on the inner surface of the bottom wall 71 of the inverter housing 7 (inner bottom surface of the inverter housing 7). Although not particularly limited, the element mounting section 79 may be a machined surface that has undergone mechanical finishing on the inner surface of the bottom wall 71 of the inverter housing 7 (inner bottom surface of the inverter housing 7). The element mounting section 79 functions as a heat dissipation section that utilizes the low-temperature gaseous refrigerant flowing into the main housing 5 to dissipate heat from the six switching elements 61.
[0018] The circuit board 63 is fixed to the upper surface of a plurality of board mounting portions 11 disposed within the inverter housing 7 by screws 13. The board mounting portions 11 are formed protruding from the inner surface (inner bottom surface) of the bottom wall 71 of the inverter housing 7. Therefore, in this embodiment, the circuit board 63 is disposed within the inverter housing 7 at a position closer to the cover member 8 than the six switching elements 61, i.e., from the six switching elements 61 toward the cover member 8 side (…). Figure 1 (Above) Separate configuration.
[0019] Each of the six switching elements 61 has a lead 61a extending toward the circuit board 63, and further, has a lead 61a extending through the circuit board 63. Moreover, these leads 61a are electrically connected to the circuit board 63, for example, by soldering to it.
[0020] Here, refer to Figures 2-4 The fixing structure of the switching element 61 of the inverter 6 of the electric compressor 1 in the embodiment will be described. Figure 2 This is a front view of the fixed structure of the switching element 61. Figure 3 This is a top view of the fixed structure of the switching element 61. Figure 4 This is an exploded perspective view of the fixed structure of the switching element 61.
[0021] like Figures 2-4 As shown, the fixing structure for the switching elements 61 includes a pressing member 20 for fixing the six switching elements 61 to the element mounting portion 79 disposed within the inverter housing 7. The pressing member 20 is formed of a thermally conductive material. Preferably, the pressing member 20 is formed in a plate shape from a resilient metal material. The pressing member 20 is disposed between the six switching elements 61 and the circuit board 63. The pressing member 20 is configured to fix the six switching elements 61 to the element mounting portion 79 by pressing them against the element mounting portion 79 while being fixed within the inverter housing 7.
[0022] In this embodiment, six switching elements 61 are arranged in two columns of three on the element mounting section 79 such that their respective leads 61a are on the inside, and as a whole, they are arranged in a rectangular shape when viewed from above.
[0023] Correspondingly, the pressing member 20 is also formed in a rectangular shape when viewed from above. Specifically, the pressing member 20 has a main body 21 that is rectangular when viewed from above. The main body 21 of the pressing member 20 has a size that corresponds to the overall size of the six switching elements 61 that are arranged in a rectangular shape on the element setting part 79 when viewed from above, that is, a size that can cover the six switching elements 61 to a certain extent (it does not need to be a size that strictly covers the six switching elements 61, as long as it is a size that can roughly cover the six switching elements 61). In addition, at least one opening is formed in the main body 21 of the pressing member 20 for the leads 61a of the six switching elements 61 to pass through. In this embodiment, an opening 23 that can pass through the leads 61a of the six switching elements 61 together is formed at approximately the center of the main body 21 of the pressing member 20 when viewed from above. However, it is not limited to this, and multiple openings that can each pass through a portion of the leads 61a of the six switching elements 61 may be formed in the main body 21 of the pressing member 20.
[0024] Furthermore, the pressing member 20 has multiple (four in this case) fixing parts 25a to 25d for fixing itself (i.e., the pressing member 20) within the inverter housing 7. The four fixing parts 25a to 25d of the pressing member 20 are respectively fixed to corresponding pressing member mounting parts 15a to 15d provided within the inverter housing 7 by screws 17. Thus, the pressing member 20 is fixed within the inverter housing 7, thereby fixing the six switching elements 61 to the element mounting part 79.
[0025] In this embodiment, the four pressing member mounting portions 15a to 15d are disposed separately from each other in such a way that they surround the six switching elements 61 on the element mounting portion 79. Similar to the substrate mounting portion 11, the four pressing member mounting portions 15a to 15d are formed protruding from the inner surface (inner bottom surface of the inverter housing 7) of the bottom wall 71 of the inverter housing 7. Furthermore, here, the four pressing member mounting portions 15a to 15d are formed on the element mounting portion 79. However, this is not a limitation; the four pressing member mounting portions 15a to 15d may be formed around the element mounting portion 79, or a portion may be formed on the element mounting portion 79 and the remainder formed around the element mounting portion 79.
[0026] The four fixing portions 25a to 25d of the pressing member 20 extend outward from the main body 21 in a manner corresponding to the four pressing member mounting portions 15a to 15d. Furthermore, the four fixing portions 25a to 25d of the pressing member 20 are each fixed to the upper surface of the corresponding pressing member mounting portions 15a to 15d by screws 17. Therefore, the four fixing portions 25a to 25d of the pressing member 20, like the four pressing member mounting portions 15a to 15d, are separately arranged to surround the six switching elements 61 when viewed from above.
[0027] Specifically, in this embodiment, the four push-button mounting portions 15a-15d provided within the inverter housing 7 are arranged at equal intervals in the circumferential direction, surrounding the six switching elements 61 on the element mounting portion 79 (they do not need to be strictly equal, as long as they are approximately equal; the same applies hereinafter). Correspondingly, the four fixing portions 25a-25d of the push-button 20 are also arranged at equal intervals in the circumferential direction, surrounding the six switching elements 61 on the element mounting portion 79 when viewed from above. Furthermore, the four fixing portions 25a-25d of the push-button 20 extend outward from the center (not strictly the center, as long as it is approximately the center) of any one of the four sides constituting the outer edge of the main body portion 21 of the push-button 20. In this case, as Figure 3 As shown, among the four fixing parts 25a to 25d of the pressing member 20, fixing parts 25a and 25b are arranged to face each other with two switching elements 61 in between.
[0028] Furthermore, the pressing member 20 has six (i.e., the same number as the switching elements 61) element pressing portions 27. The six element pressing portions 27 are respectively provided in the main body 21 at a position outside the opening 23 and protrude downward. The six element pressing portions 27 of the pressing member 20 are configured such that they are fixed to the corresponding pressing member mounting portions 15a-15d by the four fixing portions 25a-25d of the pressing member 20 by screws 17, thereby contacting the upper surface of any one of the six switching elements 61 and pressing any one of the six switching elements 61 onto the element setting portion 79.
[0029] Furthermore, the "pressing component mounting portions 15a-15d" and "component pressing portion 27" in this embodiment correspond to the "mounting portion" and "pressing portion" of the present invention, respectively. In addition, the fixing portion 25a and the fixing portion 25b correspond to the "pair of fixing portions" of the present invention.
[0030] According to the embodiment, the electric compressor 1 can achieve the following effects, for example.
[0031] In the electric compressor 1 of the embodiment, a plurality of (six) switching elements 61 constituting the inverter 6 are fixed to an element mounting section 79 provided inside the inverter housing 7 by a pressing member 20. The element mounting section 79 functions as a heat dissipation section. The pressing member 20 is formed of a flexible metal material, that is, a material that is both flexible and has good thermal conductivity. In addition, the pressing member 20 is disposed between the six switching elements 61 and the circuit board 63, and includes: four fixing parts 25a to 25d, which are fixed to four pressing member mounting parts 15a to 15d provided inside the inverter housing 7; and six element pressing parts 27, which respectively contact the upper surface of any one of the six switching elements 61, pressing any one of the six switching elements 61 onto the element mounting section 79.
[0032] Since the six switching elements 61 are pressed against the element mounting portion 7, which functions as a heat dissipation portion, by the six element pressing portions 27 of the pressing member 20, the heat of the six switching elements 61 can be stably dissipated. Furthermore, since the pressing member 20 is made of a material with good thermal conductivity, the heat of the six switching elements 61 can also be dissipated via the pressing member 20. Therefore, the electric compressor 1 according to the embodiment achieves higher cooling performance for the switching elements 61 compared to conventional methods.
[0033] Furthermore, the four fixing portions 25a to 25d of the pressing member 20 are separately arranged to surround the six switching elements 61 on the element mounting portion 79. Specifically, the six switching elements 61 are arranged in a rectangular shape on the element mounting portion 79 when viewed from above. The pressing member 20 has a rectangular main body 21, which has a size corresponding to the total size of the six switching elements 61 arranged on the element mounting portion 79. An opening 23 is formed in the main body 21 for the lead wires 61a of the six switching elements 61 to pass through. Moreover, six element pressing portions 27 are provided on the main body 21, and the four fixing portions 25a to 25d extend outward from the center of any one of the four sides constituting the outer edge of the main body 21.
[0034] Therefore, the six switching elements 61 can be stably fixed by the pressing member 20, and the four fixing parts 25a to 25d are well balanced relative to the six element pressing parts 27. The heat of the six switching elements 61 can also be stably dissipated through the four fixing parts 25a to 25d.
[0035] Furthermore, in the above embodiment, the pressing member 20 has four fixing portions 25a to 25d, each extending outward from the center of any one of the four sides constituting the outer edge of the main body 21. However, it is not limited to this. For example, as... Figure 5 As shown, the pressing member 20 may also have six fixing parts 25a to 25f (in addition, Figure 5 Although not explicitly stated, it is of course true that six pressing parts are also provided (e.g., in this case, such as...). Figure 5 As shown, among the six fixing parts 25a to 25f, fixing parts 25a and 25b can be configured to face each other with two switching elements 61 that form different columns, fixing parts 25c and 25d can be configured to face each other with three switching elements 61 that form one column, and fixing parts 25e and 25f can be configured to face each other with three switching elements 61 that form another column.
[0036] Alternatively, although the illustration is omitted, it can also be configured such that a heat dissipation component (heat sink) is provided on the component setting section 79, and the six component pressing sections 27 of the pressing component 20 press the six switching elements 61 onto the component setting section 79 via the heat dissipation component (heat sink).
[0037] The embodiments and variations of the present invention have been described above. However, the present invention is not limited to the above embodiments and variations, and further modifications can be made based on the technical concept of the present invention. Explanation of reference numerals in the attached figures:
[0038] 1: Electric compressor; 2: Rotating shaft; 3: Electric motor; 4: Compression mechanism; 5: Main body housing; 6: Inverter; 7: Inverter housing; 8: Cover component; 11: Substrate mounting part; 15a-15d: Pressing component mounting part (mounting part); 20: Pressing component; 21: Main body part; 23: Opening part; 25a-25f: Fixing part; 27: Component pressing part (pressing part); 61: Switching element; 61a: Lead wire; 63: Circuit board.
Claims
1. An electric compressor, wherein, The electric compressor includes: an electric motor for rotating a rotating shaft; a compression mechanism driven by the rotation of the rotating shaft; and an inverter for driving and controlling the electric motor, the inverter being housed in an inverter housing. The inverter includes multiple switching elements. The plurality of switching elements are fixed to the element mounting section disposed within the inverter housing by a pressing component. The pressing component has: multiple fixing parts fixed to the mounting parts disposed within the inverter housing; and multiple pressing parts for pressing any one of the multiple switching elements onto the element mounting parts, the pressing component being formed of a thermally conductive material.
2. The electric compressor according to claim 1, wherein, The inverter also includes a circuit board, which is electrically connected to the plurality of switching elements and is equipped with a control circuit that controls the operation of the plurality of switching elements. The pressing component is formed of a resilient metal material and is disposed between the plurality of switching elements and the circuit board.
3. The electric compressor according to claim 1 or 2, wherein, The plurality of fixing portions of the pressing component are configured separately from each other in such a way that they surround the plurality of switching elements when viewed from above.
4. The electric compressor according to claim 3, wherein, The plurality of switching elements, as a whole, are arranged in a rectangular shape on the element mounting section when viewed from above. The pressing component has a rectangular body portion, the body portion having a size corresponding to the overall size of the plurality of switching elements and forming at least one opening for leads of the plurality of switching elements to pass through. The plurality of pressing parts are disposed on the main body. The plurality of fixed parts extend outward from any one of the four sides constituting the outer edge of the main body.
5. The electric compressor according to claim 4, wherein, The plurality of fixed parts extend outward from the center of any one of the four sides that constitute the outer edge of the main body.
6. The electric compressor according to claim 4, wherein, The plurality of fixing parts include a pair of fixing parts, which are configured such that they are spaced apart from at least two of the plurality of switching elements.