Motor drive device

Abstract

A motor drive device (1) according to the present disclosure comprises a heat sink (3) that cools a power module (2). The heat sink comprises: a base (4) having a first surface (7) on which the power module is provided and a second surface (8) located on the opposite side from the first surface; a plurality of fins (5) arranged in parallel on the second surface; and a cover (6) having a facing wall part (9) that faces the second surface and is disposed such that the plurality of fins are located between the facing wall part and the base, a first side wall part (10) that closes the gap between the ends of the base and the facing wall part on one end side in the arrangement direction of the plurality of fins, and a second side wall part (11) that closes the gap between the ends of the base and the facing wall part on the other end side in the arrangement direction. In a tubular body (13) formed by the base and the cover, a gap between adjacent fins is defined as a flow path (14) through which a fluid passes, and the base and / or the facing wall part has a communicating port (17) that connects the flow path with the outside of the tubular body.

Description

Motor drive device

[0001] The present disclosure relates to a motor drive device.

[0002] The motor drive device includes a heat sink for cooling a power module that is a heating element. When a plurality of power modules are mounted on the heat sink, the plurality of power modules are arranged in series along the flow path of the fluid flowing in the heat sink, or are arranged in parallel in a direction orthogonal to the flow path. When the plurality of power modules are arranged in series along the flow path, the heat sink is provided with a power module located on the upstream side of the flow path and a power module located on the downstream side of the flow path.

[0003] Japanese Unexamined Patent Application Publication No. 2001-60788

[0004] When the plurality of power modules are arranged in series along the flow path, the fluid flowing in the heat sink is heated by the plurality of power modules as it goes to the downstream side of the flow path. Therefore, the temperature of the fluid flowing in the heat sink becomes higher on the downstream side of the flow path than on the upstream side of the flow path, so the temperature of the power module located on the downstream side of the flow path tends to be higher than the temperature of the power module located on the upstream side of the flow path. Accordingly, the temperature difference between the power module located on the upstream side of the flow path and the power module located on the downstream side of the flow path becomes large, so the output of the motor drive device is limited to the output corresponding to the temperature of the power module located on the downstream side of the flow path.

[0005] In order to solve the above-described problems, a motor drive device that can reduce the temperature difference between the temperature of the fluid on the upstream side of the flow path and the temperature of the fluid on the downstream side of the flow path without reducing the cooling efficiency is desired.

[0006] The motor drive device of the present disclosure is a motor drive device equipped with a heat sink for cooling a power module, the heat sink comprising: a base having a first surface on which the power module is provided and a second surface located opposite to the first surface; a plurality of fins arranged in parallel on the second surface; an opposing wall portion facing the second surface and positioned between the plurality of fins and the base; a cover having a first side wall portion that closes the space between the ends of the base and the opposing wall portion at one end in the direction of arrangement of the plurality of fins; and a second side wall portion that closes the space between the ends of the base and the opposing wall portion at the other end in the direction of arrangement, wherein the space between adjacent fins within the cylindrical body formed by the base and the cover serves as a fluid passage, and at least one of the base or the opposing wall portion has a communication opening that connects the fluid passage to the outside of the cylindrical body.

[0007] This is a schematic perspective view showing a motor drive device according to Embodiment 1 of the present invention, viewed from the front. This is a schematic perspective view showing a motor drive device according to Embodiment 1 of the present invention, viewed from the rear. This is a schematic right side view of a motor drive device according to Embodiment 1 of the present invention, showing the heat sink in cross-section. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 2 of the present invention. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 3 of the present invention. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 4 of the present invention. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 5 of the present invention. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 6 of the present invention. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 7 of the present invention, viewed from the front. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 7 of the present invention, viewed from the rear. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 8 of the present invention. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 8 of the present invention, showing a case where the position of the communication port is different from the state in Figure 11. This is a schematic longitudinal cross-sectional view showing the heat sink of a motor drive device according to Embodiment 9 of the present invention, showing a state in which fluid is flowing into the heat sink toward the downstream side of the flow path. This is a schematic longitudinal cross-sectional view showing the heat sink of a motor drive device according to Embodiment 9 of the present invention, showing the state in which fluid is flowing into the heat sink toward the upstream side of the flow path. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 10 of the present invention, showing the state as seen from the front. This is a schematic perspective view showing the heat sink of a motor drive device according to Embodiment 10 of the present invention, showing the state as seen from the rear. This is a schematic longitudinal cross-sectional view showing the heat sink of a motor drive device according to Embodiment 11 of the present invention.

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. A motor drive device 1 according to Embodiment 1 will be described with reference to Figures 1 to 3. The motor drive device 1 includes a power module 2 for controlling a motor (not shown) and a heat sink 3 for cooling the power module 2. Here, a case in which the motor drive device 1 includes a plurality of power modules 2 will be described. In the illustrated example, the motor drive device 1 includes three power modules 2, but is not limited to this, and may include two power modules or four or more power modules. The heat sink 3 has a base 4, a plurality of fins 5, and a cover 6.

[0009] The base 4 has a first surface 7 on which multiple power modules 2 are provided, and a second surface 8 located on the opposite side of the first surface 7. The base 4 is a plate-like structure that is roughly rectangular in front view, with the vertical direction as its longitudinal direction. The first surface 7 of the base 4 is the front surface, which is one of the plate surfaces of the base 4. Multiple power modules 2 are arranged in series vertically on the first surface 7 of the base 4. The second surface 8 of the base 4 is the rear surface, which is the other plate surface of the base 4.

[0010] Multiple fins 5 are arranged in parallel on the second surface 8 of the base 4, from left to right. Each fin 5 is a roughly rectangular plate with its longitudinal direction in the vertical direction. When each fin 5 is provided on the second surface 8 of the base 4, the longitudinal direction of each fin 5 is aligned with the vertical direction, and the short direction of each fin 5 is aligned with the front-to-back direction. In this way, each fin 5 extends rearward from the second surface 8 of the base 4. When multiple fins 5 are provided on the base 4, gaps are formed between adjacent fins 5, 5 along the vertical direction.

[0011] The cover 6 is provided on the base 4 so as to cover a plurality of fins 5 provided on the base 4. The cover 6 has an opposing wall portion 9 located on the rear side of the base 4, a first side wall portion 10 located on the left side of the base 4, and a second side wall portion 11 located on the right side of the base 4.

[0012] The opposing wall portion 9 is a plate-like structure with a roughly rectangular shape when viewed from the rear, with the vertical direction as its longitudinal direction. A first side wall portion 10 is provided at the left end, which is one end of the opposing wall portion 9 in the short direction. The first side wall portion 10 is a plate-like structure with a roughly rectangular shape when viewed from the side, with the vertical direction as its longitudinal direction. When the first side wall portion 10 is provided on the opposing wall portion 9, the longitudinal direction of the first side wall portion 10 is aligned with the vertical direction, and the short direction of the first side wall portion 10 is aligned with the front-to-back direction. In this way, the first side wall portion 10 extends forward from the left end of the opposing wall portion 9. A second side wall portion 11 is provided at the right end, which is the other end of the opposing wall portion 9 in the short direction. The second side wall portion 11 is a plate-like structure with a roughly rectangular shape when viewed from the side, with the vertical direction as its longitudinal direction. In the state where the second side wall portion 11 is provided on the opposing wall portion 9, the longitudinal direction of the second side wall portion 11 is aligned with the vertical direction, and the short direction of the second side wall portion 11 is aligned with the front-rear direction. In this way, the second side wall portion 11 extends forward from the right end of the opposing wall portion 9.

[0013] The cover 6, which has an opposing wall portion 9, a first side wall portion 10, and a second side wall portion 11, has a groove shape that opens forward. The cover 6 has a groove shape with the opposing wall portion 9 as the bottom wall and the first side wall portion 10 and the second side wall portion 11 as the side walls. The groove-shaped cover 6 is provided on the base 4 so as to form a hollow portion 12 between it and the base 4. Specifically, the front end of the first side wall portion 10 is fixed to the left end of the base 4, and the front end of the second side wall portion 11 is fixed to the right end of the base 4, thereby fixing the cover 6 to the base 4. When the cover 6 is fixed to the base 4, a hollow portion 12 that opens in the vertical direction is formed between the cover 6 and the base 4, and a plurality of fins 5 provided on the base 4 are arranged in this hollow portion 12. Note that the cover 6 and the base 4 are not limited to being separate parts, but may be formed as a single unit.

[0014] With the cover 6 fixed to the base 4, the opposing wall portion 9, the first side wall portion 10, and the second side wall portion 11 are arranged as follows: The opposing wall portion 9 faces the second surface 8 of the base 4 in the front-rear direction and is positioned at a distance from the base 4 in the front-rear direction so that a plurality of fins 5 are positioned between it and the base 4. The first side wall portion 10 closes the space between the left ends of the base 4 and the opposing wall portion 9 at the left end side, which is one end in the direction of arrangement of the plurality of fins 5. The second side wall portion 11 closes the space between the right ends of the base 4 and the opposing wall portion 9 at the right end side, which is the other end in the direction of arrangement of the plurality of fins 5.

[0015] The cover 6 is fixed to the base 4, forming a cylindrical body 13 by the base 4 and the cover 6. The cylindrical body 13 has a roughly rectangular shape in plan view, with both axial ends open. Multiple fins 5 are arranged in the hollow portion 12 inside the cylindrical body 13, as described above. Inside the cylindrical body 13, the gaps between adjacent fins 5, 5 are fluid passages 14 for cooling the power module 2. Therefore, multiple passages 14 are arranged in parallel from left to right inside the cylindrical body 13. Each passage 14 extends along the vertical direction and opens vertically. Gaps are formed between the leftmost fin 5 and the first side wall portion 10, and between the rightmost fin 5 and the second side wall portion 11. Fluid also passes through these gaps.

[0016] The fluid flowing through the flow path 14 is, for example, a gas. When the fluid is a gas, the gas in the flow path 14 is heated by the heat from the power module 2, which can generate an upward airflow within the flow path 14. Therefore, the fluid outside the cylindrical body 13 flows into the flow path 14 from the intake port 15 located on the lower side of the cylindrical body 13, flows upward within the flow path 14, and is then discharged to the outside of the cylindrical body 13 from the exhaust port 16 located on the upper side of the cylindrical body 13.

[0017] The opposing wall portion 9 of the cylindrical body 13 has a communication opening 17 that connects the inside and outside of the cylindrical body 13. Since the communication opening 17 connects the inside and outside of the cylindrical body 13, it connects the flow path 14 to the outside of the cylindrical body 13. In the illustrated example, the communication opening 17 is substantially rectangular in shape, with the left-right direction, which is the direction in which the multiple fins 5 are arranged, as its longitudinal direction. The width of the communication opening 17 in the vertical direction, which is perpendicular to the direction in which the multiple fins 5 are arranged, is uniform across the left-right direction. The communication opening 17 opens across the entire left-right direction of the opposing wall portion 9. That is, the communication opening 17 opens between the first side wall portion 10 located on the left side and the second side wall portion 11 located on the right side. Therefore, all the flow paths 14 formed inside the cylindrical body 13 are in communication with the outside of the cylindrical body 13 through the communication opening 17.

[0018] As described above, the multiple power modules 2 are arranged vertically in series on the first surface 7 of the base 4. In other words, the multiple power modules 2 are arranged on the first surface 7 of the base 4 along the direction in which the flow path 14 extends. When the motor drive device 1 is equipped with multiple power modules 2, the communication port 17 is located upstream of the flow path 14, rather than downstream of the adjacent power modules 2, 2. In the illustrated example, the communication port 17 is formed in the opposing wall portion 9 at a position facing the space between the power module 2 located furthest downstream and the power module 2 located in the center adjacent to it.

[0019] Next, we will describe the case where the power module 2 is cooled by the heat sink 3. As mentioned above, an upward airflow is generated in the flow path 14, causing gas from outside the cylindrical body 13 to flow into the multiple flow paths 14 from the intake port 15. The gas that flows into the flow paths 14 flows upward through the flow paths 14. The gas flows through the flow paths 14 while in contact with the fins 5. The gas that reaches the upper end of the flow paths 14 is discharged to the outside of the cylindrical body 13 through the exhaust port 16. In this way, the gas flowing through the flow paths 14 can cool the multiple power modules 2 provided on the first surface 7 of the base 4.

[0020] If the communication port 17 is not formed, the gas flowing through the flow path 14 is heated as it flows downstream by the multiple power modules 2 arranged vertically along the first surface 7 of the base 4. As a result, when the power modules 2 are cooled, the power module 2 located furthest downstream will have a higher temperature than the other power modules 2.

[0021] In contrast, in the motor drive device 1 of Embodiment 1, the opposing wall portion 9 has a communication port 17. The communication port 17 is formed in the opposing wall portion 9 at a position opposite to the space between the power module 2 located furthest downstream and the power module 2 adjacent to it. Therefore, according to the motor drive device 1 of Embodiment 1, gas from outside the cylindrical body 13 can flow into the flow path 14 through the communication port 17 by the rising airflow generated in the flow path 14. The gas that flows into the flow path 14 from the communication port 17 flows downstream of the communication port 17 in the flow path 14 and is then discharged from the exhaust port 16. Therefore, the power module 2 located furthest downstream is cooled by fresh outside air from the communication port 17. This makes it possible to lower the temperature of the power module 2 located furthest downstream. According to the motor drive device 1 of Embodiment 1, when a plurality of power modules 2 with different outputs are arranged on the base 4, the power module 2 with the higher temperature can be preferentially cooled by appropriately setting the vertical position of the communication port 17 in the opposing wall portion 9. For example, in the motor drive device 1 of Embodiment 1, the power module 2 with a high output can be cooled preferentially.

[0022] In the motor drive device 1 of Embodiment 1, gas from outside the cylindrical body 13 can flow into the flow path 14 from the intake port 15 and also from the communication port 17. Therefore, according to the motor drive device 1 of Embodiment 1, since there are multiple locations on the heat sink 3 where gas is supplied into the flow path 14, clogging of the locations where gas is supplied into the flow path 14 can be dispersed compared to the case where the intake port 15 is the only location where gas is supplied into the flow path 14. This suppresses clogging of the heat sink 3.

[0023] Next, the motor drive device 1a according to Embodiment 2 will be described with reference to Figure 4. Note that components having the same reference numerals as those used in Embodiment 1 will have the same function and therefore their descriptions may be omitted below. The motor drive device 1a of Embodiment 2 differs from Embodiment 1 in the configuration of the communication port 17 of the heat sink 3.

[0024] In Embodiment 2, the communication opening 17 is partially open in the opposing wall portion 9. The communication opening 17 is substantially rectangular in shape, with the left-right direction, which is the direction in which the multiple fins 5 are arranged, as its longitudinal direction. The left-right length of the communication opening 17 is smaller than the left-right length of the opposing wall portion 9. The communication opening 17 is provided in the opposing wall portion 9, leaving both the left and right ends of the opposing wall portion 9 intact. Therefore, the communication opening 17 opens in such a way that it leaves a portion of the opposing wall portion 9 open in the left-right direction. The width of the communication opening 17 is uniform in the vertical direction, which is the direction perpendicular to the direction in which the multiple fins 5 are arranged.

[0025] The communication opening 17, configured in this way, is positioned approximately in the center of the opposing wall section 9 in the left-right direction. The communication opening 17 is formed in the opposing wall section 9 at a position opposite to the space between the power module 2 located furthest downstream and the power module 2 located in the center adjacent to it.

[0026] In Embodiment 2, the power module 2 located furthest downstream is located approximately in the center of the first surface 7 in the left-right direction. The part of the power module 2 that generates the most heat is approximately in the center of the power module 2 in the left-right direction. Therefore, when the power module 2 is placed approximately in the center of the first surface 7 in the left-right direction, the part of the power module 2 that generates the most heat is located approximately in the center of the first surface 7 in the left-right direction. In the illustrated example, the remaining two power modules 2 are located approximately in the center of the first surface 7 in the left-right direction.

[0027] According to the motor drive device 1a of Embodiment 2, the gas from the communication port 17 is supplied only to the flow path 14 corresponding to the part of the power module 2 that generates the most heat. Therefore, the part that needs to be cooled can be cooled locally.

[0028] Next, the motor drive device 1b according to Embodiment 3 will be described with reference to Figure 5. Note that components having the same reference numerals as those used in Embodiment 1 will have the same function and therefore their descriptions may be omitted below. The motor drive device 1b of Embodiment 3 differs from Embodiment 1 in the configuration of the communication port 17 of the heat sink 3.

[0029] In Embodiment 3, the width of the communication opening 17 is not uniform in the vertical direction, which is perpendicular to the arrangement direction of the fins 5. In the illustrated example, the communication opening 17 is approximately parallelogram-shaped when viewed from the rear. Of the two diagonals of the communication opening 17, which is approximately parallelogram-shaped when viewed from the rear, the longer diagonal runs in the left-right direction, and the shorter diagonal runs in the vertical direction. The left-right length of the longer diagonal of the two diagonals of the communication opening 17 is smaller than the left-right length of the opposing wall portion 9. The communication opening 17 is provided in the opposing wall portion 9, leaving both the left and right ends of the opposing wall portion 9. Therefore, the communication opening 17 opens up in the opposing wall portion 9 so as to leave a part of it open in the left-right direction. Note that the shape of the communication opening 17 in Embodiment 3 is not limited to a parallelogram, and any shape in which the width in the vertical direction is not uniform is acceptable.

[0030] The communication opening 17, configured in this way, is positioned approximately in the center of the opposing wall section 9 in the left-right direction. The communication opening 17 is formed in the opposing wall section 9 at a position opposite to the space between the power module 2 located furthest downstream and the power module 2 located in the center adjacent to it.

[0031] In Embodiment 3, the power module 2 located furthest downstream is located approximately in the center of the first surface 7 in the left-right direction. The part of the power module 2 that generates the most heat is approximately in the center of the power module 2 in the left-right direction. Therefore, when the power module 2 is placed approximately in the center of the first surface 7 in the left-right direction, the part of the power module 2 that generates the most heat is located approximately in the center of the first surface 7 in the left-right direction. In the illustrated example, the remaining two power modules 2 are located approximately in the center of the first surface 7 in the left-right direction.

[0032] According to the motor drive device 1b of Embodiment 3, the gas from the communication port 17 is supplied only to the flow path 14 corresponding to the part of the power module 2 that generates the most heat. In particular, a large amount of gas can be flowed into the flow path 14 from the approximately central part of the communication port 17 in the left-right direction. Therefore, the part that needs to be cooled can be cooled locally.

[0033] Next, the motor drive device 1c according to Embodiment 4 will be described with reference to Figure 6. Note that components having the same reference numerals as those used in Embodiment 1 will have the same function and therefore their descriptions may be omitted below. The motor drive device 1c of Embodiment 4 differs from Embodiment 1 in the configuration of the communication port 17 of the heat sink 3.

[0034] In Embodiment 4, the communication openings 17 are arranged in the left-right direction, which is the direction in which the fins 5 are arranged, on the opposing wall portion 9. The lengths of the multiple communication openings 17 differ in the left-right direction, which is the direction in which the fins 5 are arranged. In the illustrated example, the opposing wall portion 9 has two communication openings 17, 17 that are spaced apart in the left-right direction. The two communication openings 17, 17 are substantially rectangular in shape with the left-right direction as the longitudinal direction. The left-right length of one communication opening 17 is greater than the left-right length of the other communication opening 17. The top-bottom length of one communication opening 17 is approximately the same as the top-bottom length of the other communication opening 17. Note that the lengths of the multiple communication openings 17 in the left-right direction, which is the direction in which the fins 5 are arranged, may be approximately the same.

[0035] According to the motor drive device 1c of Embodiment 4, since the multiple communication ports 17 are arranged along the left-right direction, multiple parts to be cooled can be cooled locally. For example, the motor drive device 1c of Embodiment 4 is suitable when multiple power modules 2 are arranged in the left-right direction, or when the chips provided inside the power modules 2 are arranged in the left-right direction. If the left-right lengths of each of the multiple communication ports 17 are different, the parts to be cooled can be cooled locally even if the sizes of the multiple parts to be cooled are different.

[0036] Next, the motor drive device 1d according to Embodiment 5 will be described with reference to Figure 7. Note that components having the same reference numerals as those used in Embodiment 1 will have the same function and therefore their descriptions may be omitted below. The motor drive device 1d of Embodiment 5 differs from Embodiment 1 in the configuration of the communication port 17 of the heat sink 3.

[0037] In Embodiment 5, the communication openings 17 are arranged in a vertical direction perpendicular to the arrangement direction of the multiple fins 5 in the opposing wall portion 9. In the illustrated example, the opposing wall portion 9 has two communication openings 17, 17 that are separated in the vertical direction. The two communication openings 17, 17 are each substantially rectangular in shape with the left-right direction as their longitudinal direction. The width of the two communication openings 17, 17 is uniform in the vertical direction, which is perpendicular to the arrangement direction of the multiple fins 5, across the left-right direction. The vertical width of one communication opening 17 is approximately the same as the vertical width of the other communication opening 17. The two communication openings 17, 17 each open across the entire left-right direction of the opposing wall portion 9. Note that the two communication openings 17, 17 are not limited to having a shape with a uniform width in the vertical direction, but may have a shape with an uneven width in the vertical direction.

[0038] Of the two communication openings 17, 17, the upper communication opening 17 is formed in the opposing wall 9 at a position facing the space between the power module 2 located furthest downstream and the power module 2 located in the center adjacent to it. Of the two communication openings 17, 17, the lower communication opening 17 is formed in the opposing wall 9 at a position facing the space between the power module 2 located furthest upstream and the power module 2 located in the center adjacent to it.

[0039] According to the motor drive device 1d of Embodiment 5, the power module 2 located furthest downstream can be cooled by fresh outside air from the communication port 17 located at the top, and the power module 2 located in the center can be cooled by fresh outside air from the communication port 17 located at the bottom. Therefore, by arranging multiple communication ports 17 in the vertical direction, the temperature distribution of multiple power modules 2 can be finely adjusted.

[0040] Next, the motor drive device 1e according to Embodiment 6 will be described with reference to Figure 8. Note that components having the same reference numerals as those used in Embodiment 1 have the same function, so their descriptions may be omitted below. The motor drive device 1e of Embodiment 6 differs from Embodiment 1 in the configuration of the communication port 17 of the heat sink 3.

[0041] In Embodiment 6, the communication openings 17 are arranged in a vertical direction perpendicular to the arrangement direction of the multiple fins 5 in the opposing wall portion 9. The multiple communication openings 17 arranged in a direction perpendicular to the arrangement direction of the multiple fins 5 have different lengths in that direction. In the illustrated example, the opposing wall portion 9 has two communication openings 17, 17 that are separated in the vertical direction. The two communication openings 17, 17 are each substantially rectangular in shape with the left-right direction as their longitudinal direction. The width of the two communication openings 17, 17 is uniform in the vertical direction perpendicular to the arrangement direction of the multiple fins 5 across the left-right direction. The vertical width of one communication opening 17 is greater than the vertical width of the other communication opening 17. The two communication openings 17, 17 each open across the entire left-right direction of the opposing wall portion 9.

[0042] The vertical length of the upper of the two communication openings 17, 17 is greater than the vertical length of the lower of the two communication openings 17, 17. The upper communication opening 17 is formed in the opposing wall 9 at a position opposite to the space between the downstream power module 2 and the adjacent central power module 2. The lower communication opening 17 is formed in the opposing wall 9 at a position opposite to the space between the upstream power module 2 and the adjacent central power module 2.

[0043] As mentioned above, the fluid flows from bottom to top within the flow path 14. Therefore, the temperature of the fluid flowing near the power module 2 located furthest downstream is higher than the temperature of the fluid flowing near the power module 2 located in the center.

[0044] According to the motor drive device 1e of Embodiment 6, since the vertical length of the communication port 17 located on the upper side is larger than the vertical length of the communication port 17 located on the lower side, the fluid with a high temperature can be cooled by a large amount of fresh outside air, and the fluid with a low temperature can be cooled by a small amount of fresh outside air. Therefore, by arranging a plurality of communication ports 17 with different sizes in the vertical direction, the temperature distribution of the plurality of power modules 2 can be adjusted more finely.

[0045] Next, the motor drive device 1f according to Embodiment 7 will be described with reference to FIGS. 9 and 10. In addition, components having the same reference numerals as those in Embodiment 1 may have the same operations, and thus the description may be omitted hereinafter.

[0046] The plurality of power modules 2 arranged in the vertical direction are shifted from each other in the left-right direction. In the illustrated example, the power module 2 located at the lowermost position is located at substantially the center in the left-right direction of the first surface 7, the power module 2 located at the uppermost position is located on the right side of the center in the left-right direction on the first surface 7, and the power module 2 located in the center is located on the left side of the center in the left-right direction on the first surface 7.

[0047] A plurality of communication ports 17 are arranged in the vertical direction, which is a direction orthogonal to the arrangement direction of the plurality of fins 5, in the opposing wall portion 9. The plurality of communication ports 17 arranged in the direction orthogonal to the arrangement direction of the plurality of fins 5 are shifted from each other in the left-right direction, which is the arrangement direction of the plurality of fins 5. In the illustrated example, the opposing wall portion 9 has two communication ports 17, 17 spaced apart in the vertical direction. The two communication ports 17, 17 are shifted from each other in the left-right direction. Specifically, one communication port 17 is located on the left side of the center in the left-right direction in the opposing wall portion 9, and the other communication port 17 is located on the right side of the center in the left-right direction in the opposing wall portion 9.

[0048] The two communication ports 17, 17 are each substantially rectangular with the longitudinal direction being the left-right direction. The two communication ports 17, 17 each have a uniform vertical width in the up-down direction, which is orthogonal to the arrangement direction of the plurality of fins 5, across the left-right direction. The vertical width of one communication port 17 is substantially the same as the vertical width of the other communication port 17. The left-right length of one communication port 17 is substantially the same as the left-right length of the other communication port 17. Note that the vertical width of one communication port 17 and the vertical width of the other communication port 17, and the left-right length of one communication port 17 and the left-right length of the other communication port 17 may be different.

[0049] Of the two communication ports 17, 17, the upper communication port 17 is formed in the opposing wall portion 9 at a position opposing between the power module 2 located on the most downstream side and the power module 2 located in the center adjacent thereto. Of the two communication ports 17, 17, the lower communication port 17 is formed in the opposing wall portion 9 at a position opposing between the power module 2 located on the most upstream side and the power module 2 located in the center adjacent thereto.

[0050] According to the motor drive device 1f of Embodiment 7, since the upper communication port 17 is located on the right side and the lower communication port 17 is located on the left side, it is possible to cool the fluid flowing near the power module 2 located on the uppermost side and also to cool the fluid flowing near the power module 2 located in the center. Therefore, when the plurality of power modules 2 arranged in the up-down direction are shifted from each other in the left-right direction so that the mounting positions of the plurality of power modules 2 do not form a straight line, the portion to be cooled can be locally cooled.

[0051] Next, the motor drive device 1g according to Embodiment 8 will be described using FIGS. 11 and 12. Components having the same reference numerals as those in Embodiment 1 may have the same operation, and thus the description may be omitted hereinafter.

[0052] The opposing wall section 9 consists of multiple wall materials 18 arranged in a vertical direction perpendicular to the arrangement direction of the multiple fins 5. The wall materials 18 are plate-shaped with a roughly rectangular shape when viewed from the rear. When the multiple wall materials 18 are arranged without gaps, the total vertical length is smaller than the vertical length of the base 4, the vertical length of the first side wall section 10, and the vertical length of the second side wall section 11. In the illustrated example, the number of wall materials 18 is five, but it is not limited to this.

[0053] The first side wall portion 10 and the second side wall portion 11 have rails 19 that extend in a vertical direction, which is perpendicular to the direction in which the plurality of fins 5 are arranged. The rails 19 of the first side wall portion 10 are concave in shape and open toward the second side wall portion 11, and are provided on the inner surface of the first side wall portion 10. The rails 19 of the second side wall portion 11 are concave in shape and open toward the first side wall portion 10, and are provided on the inner surface of the second side wall portion 11. In this way, the cover 6 is provided with a pair of left and right rails 19, 19.

[0054] A wall material 18 is provided on a pair of left and right rails 19, 19 so as to be slidable in the vertical direction, which is perpendicular to the arrangement direction of the multiple fins 5. Specifically, the left end of the wall material 18 is inserted into the rail 19 located on the left side, and the right end of the wall material 18 is inserted into the rail 19 located on the right side, so that the wall material 18 is slidably provided on the pair of left and right rails 19, 19. When the wall material 18 is inserted into the rails 19, applying a force in the vertical direction to the wall material 18 allows the wall material 18 to move, and when the force is removed from the wall material 18, the wall material 18 can be held in that position. Therefore, multiple wall materials 18 are movable in the vertical direction relative to the first side wall portion 10 and the second side wall portion 11, and can be held at a desired position relative to the first side wall portion 10 and the second side wall portion 11.

[0055] The communication opening 17 is the gap between adjacent wall materials 18, 18. Therefore, according to the motor drive device 1g of Embodiment 8, the vertical position of the communication opening 17 can be changed, and the number of communication openings 17 arranged in the vertical direction can be changed. Furthermore, according to the motor drive device 1g of Embodiment 8, the vertical length of each of the multiple communication openings 17 arranged in the vertical direction can be adjusted.

[0056] Next, the motor drive device 1h according to Embodiment 9 will be described with reference to Figures 13 and 14. Note that components having the same reference numerals as those used in Embodiment 1 will have the same function, and therefore their descriptions may be omitted below.

[0057] The heat sink 3 is equipped with an adjustment mechanism 20 that can change the direction of fluid flow through the communication port 17. The adjustment mechanism 20 has a pair of shafts 21, 21 and a pair of rotating plates 22, 22. Of the pair of shafts 21, 21, one shaft 21 is provided on the opposing wall portion 9 above the communication port 17. When one shaft 21 is provided on the opposing wall portion 9, the axis of the shaft 21 is aligned in the left-right direction. Of the pair of shafts 21, 21, the other shaft 21 is provided on the opposing wall portion 9 below the communication port 17. When the other shaft 21 is provided on the opposing wall portion 9, the axis of the other shaft 21 is aligned in the left-right direction. The pair of rotating plates 22, 22 are substantially rectangular plates with the left-right direction as their longitudinal direction. Of the pair of rotating plates 22, 22, one rotating plate 22 is rotatable around the shaft 21 located above it. In a state where one rotating plate 22 is held in the axial direction of the shaft 21, the longitudinal direction of the one rotating plate 22 is aligned with the left-right direction. Of the pair of rotating plates 22, 22, the other rotating plate 22 is rotatable around the shaft 21 located below it. In a state where the other rotating plate 22 is held in the axial direction of the shaft 21, the longitudinal direction of the other rotating plate 22 is aligned with the left-right direction. In an adjustment mechanism 20 with such a configuration, when a force is applied to the rotating plate 22 while it is held on the shaft 21, the rotating plate 22 can be rotated, and when the force is removed from the rotating plate 22, it can be held in that position. Note that the adjustment mechanism 20 is not limited to a configuration having a shaft 21 and a rotating plate 22.

[0058] The heat sink 3 has a flow generator 23 that generates fluid flow in the flow path 14. In the illustrated example, the flow generator 23 is a fan motor, but is not limited to this. The flow generator 23 is provided at the upper end of the heat sink 3. That is, the flow generator 23 is provided at the downstream end of the flow path 14. By operating the flow generator 23, the fluid can be forcibly made to flow from the intake port 15 to the exhaust port 16.

[0059] According to the motor drive device 1h of Embodiment 9, the direction of the fluid passing through the communication port 17 can be changed by rotating the pair of rotating plates 22, 22. Therefore, a desired power module 2 among the power modules 2 arranged in the vertical direction can be cooled without changing the vertical position of the communication port 17.

[0060] According to the motor drive device 1h of Embodiment 9, when a flow generator 23 is provided at the downstream end of the flow path 14, the airflow decreases on the upstream side of the flow path 14, so the temperature of the power module 2 located on the upstream side of the flow path 14 decreases more slowly. Therefore, the temperature difference between multiple power modules 2 can be reduced.

[0061] Next, the motor drive device 1i according to Embodiment 10 will be described with reference to Figures 15 and 16. Note that components having the same reference numerals as those used in Embodiment 1 have the same function, and therefore their descriptions may be omitted below. In Embodiment 9, the base 4 of the cylindrical body 13 has a communication port 17 that connects the inside and outside of the cylindrical body 13. When the base 4 is provided with a communication port 17, the entire heat sink 3 is placed inside the control panel.

[0062] The communication opening 17 of the base 4 connects the inside and outside of the cylindrical body 13, thus connecting the flow path 14 to the outside of the cylindrical body 13. In the illustrated example, the communication opening 17 is substantially rectangular in shape, with the left-right direction, which is the direction in which the multiple fins 5 are arranged, as its longitudinal direction. The width of the communication opening 17 in the vertical direction, which is perpendicular to the direction in which the multiple fins 5 are arranged, is uniform across the left-right direction. The communication opening 17 opens across the entire left-right direction of the base 4. That is, the communication opening 17 opens between the first side wall portion 10 located on the left side and the second side wall portion 11 located on the right side.

[0063] The communication port 17 is located between the power module 2 located furthest downstream and the power module 2 located in the center adjacent to it. Therefore, the communication port 17 of the base 4 faces the communication port 17 of the opposing wall 9 in the front-to-back direction. The communication port 17 of the base 4 may also be configured as the communication port 17 of embodiments 2 to 7.

[0064] According to the motor drive device 1i of embodiment 10, since communication openings 17 are provided in the base 4 and the opposing wall portion 9, the temperature of the power module 2 located on the downstream side can be lowered more reliably.

[0065] Next, the motor drive device 1j according to Embodiment 11 will be described with reference to Figure 17. Note that components having the same reference numerals as those used in Embodiment 1 will have the same function, and therefore their descriptions may be omitted below.

[0066] A power module 2, which is roughly rectangular in front view and has its longitudinal direction in the vertical direction, is provided on the first surface 7 of the base 4. The power module 2 has a plurality of heat-generating parts 24 arranged along the direction in which the flow path 14 extends. In the illustrated example, the heat-generating parts 24 are chips provided on the power module 2. The communication opening 17 provided in the opposing wall 9 is located upstream of the flow path 14, rather than the heat-generating part 24 located downstream of the flow path 14 among the adjacent heat-generating parts 24, 24.

[0067] According to the motor drive device 1j of Embodiment 11, the heat-generating section 24 located downstream of the communication port 17 can be cooled by fresh outside air from the communication port 17. This makes it possible to lower the temperature of the heat-generating section 24 located downstream of the communication port 17.

[0068] According to at least one embodiment described above, a communication port 17 is provided in the heat sink 3. The communication port 17 is not provided in at least one of the first side wall portion 10 or the second side wall portion 11. If the communication port 17 is provided in at least one of the first side wall portion 10 or the second side wall portion 11, a large amount of outside air will flow into at least one of the gap between the first side wall portion 10 and the fin 5, or the gap between the second side wall portion 11 and the fin 5. In this case, the fluid will come into contact with the fin 5, which is not very hot, so the cooling efficiency will be reduced. Therefore, a motor drive device 1 can be provided that can reduce the temperature difference between the fluid temperature on the upstream side of the flow path 14 and the fluid temperature on the downstream side of the flow path 14 without reducing the cooling efficiency.

[0069] While this disclosure has been described in detail, it is not limited to the individual embodiments described above. These embodiments can be added, replaced, modified, partially deleted, etc., in any way that does not depart from the gist of this disclosure or from the spirit of this disclosure derived from the claims and their equivalents. Furthermore, these embodiments can be implemented in combination. For example, the order of operations and processes in the embodiments described above are given as examples only and are not limited thereto. The same applies when numerical values ​​or mathematical formulas are used in the description of the embodiments described above.

[0070] The communication opening 17 may be provided in either the base 4 or the opposing wall portion 9, or it may be provided in both the base 4 and the opposing wall portion 9. That is, at least one of the base 4 or the opposing wall portion 9 has a communication opening 17 that connects the flow path 14 to the outside of the cylindrical body 13.

[0071] With respect to the above embodiment, the following additional information is disclosed. (Addendum 1) The motor drive device (1) is a motor drive device comprising a heat sink (3) for cooling a power module (2), wherein the heat sink (3) comprises a base (4) having a first surface (7) on which the power module (2) is provided and a second surface (8) located on the opposite side of the first surface (7), a plurality of fins (5) arranged in parallel on the second surface (8), an opposing wall portion (9) facing the second surface (8) and positioned between the plurality of fins (5) and the base (4), and the base ( 4) A cover (6) having a first side wall portion (10) that closes the space between the ends of the base (4) and the opposing wall portion (9), and a second side wall portion (11) that closes the space between the ends of the base (4) and the opposing wall portion (9) on the other end in the direction of arrangement, wherein the gap between adjacent fins (5, 5) forms a fluid passage (14) within the cylindrical body (13) formed by the base (4) and the cover (6), and at least one of the base (4) or the opposing wall portion (9) has a communication opening (17) that connects the fluid passage (14) to the outside of the cylindrical body (13).

[0072] (Note 1-2) In Note 1, the motor drive device (1) may have a uniform width in the direction perpendicular to the arrangement direction of the communication port (17).

[0073] (Note 2) In the motor drive device (1), the communication port (17) may be opened in such a way that it leaves open a part of the arrangement direction in at least one of the base (4) or the opposing wall portion (9).

[0074] (Note 2-2) In Note 1, the motor drive device (1) does not need to have a uniform width in the direction perpendicular to the arrangement direction of the communication port (17).

[0075] (Note 3) In the motor drive device (1), in Note 1, the communication ports (17) may be arranged in multiple rows in the direction of the arrangement.

[0076] (Note 4) In the motor drive device (1), as stated in Note 3, the multiple communication ports (17) may have different lengths in the direction of arrangement.

[0077] (Note 5) In any of Notes 1 to 4, the motor drive device (1) may have multiple communication ports (17) arranged in a direction perpendicular to the arrangement direction.

[0078] (Note 6) In the motor drive device (1), the plurality of communication ports (17) arranged in a direction perpendicular to the arrangement direction may be offset from each other in the arrangement direction.

[0079] (Note 7) In any of Notes 1 to 6, the motor drive device (1) is such that the opposing wall portion (9) consists of a plurality of wall materials (18) arranged in a direction perpendicular to the arrangement direction, the plurality of wall materials (18) are movable relative to the first side wall portion (10) and the second side wall portion (11) in a direction perpendicular to the arrangement direction, and the communication opening (17) may be the gap between adjacent wall materials (18, 18).

[0080] (Note 8) In the motor drive device (1), the first side wall portion (10) and the second side wall portion (11) have rails (19) extending in a direction perpendicular to the arrangement direction, and the plurality of wall materials (18) may be provided on the rails (19) so as to be slidable in a direction perpendicular to the arrangement direction.

[0081] (Note 9) In any of Notes 1 to 8, the motor drive device (1) may further include an adjustment mechanism (20) that can change the direction of fluid flow through the communication port (17) of the heat sink (3).

[0082] (Note 9-2) In any of Notes 1 to 9, the motor drive device (1) may be provided with a flow generator (23) in the heat sink (3) that generates flow in the fluid in the flow path (14).

[0083] (Note 10) In any of Notes 1 to 9, the motor drive device (1) is provided with a plurality of power modules (2) on the first surface (7) along the direction in which the flow path (14) extends, and the communication port (17) may be located upstream of the flow path (14) among the adjacent power modules (2,2) that are located downstream of the flow path (14).

[0084] (Note 11) In Note 1, the motor drive device (1) has a power module (2) which has a plurality of heating elements (24) arranged along the direction in which the flow path (14) extends, and the communication port (17) may be located upstream of the flow path (14) of the adjacent heating elements (24, 24) that are located downstream of the flow path (14).

[0085] 1. Motor drive unit 2. Power module 3. Heat sink 4. Base 5. Fins 6. Cover 7. First surface 8. Second surface 9. Opposing wall section 10. First side wall section 11. Second side wall section 13. Cylindrical body 14. Flow path 17. Communication port 18. Wall material 19. Rail 20. Adjustment mechanism 23. Flow generator 24. Heat generating section

Claims

A motor drive device equipped with a heat sink for cooling the power module, The aforementioned heatsink is A base having a first surface on which the power module is provided and a second surface located opposite the first surface, Multiple fins arranged in parallel on the second surface, The cover comprises: an opposing wall portion facing the second surface and positioned between it and the base such that the plurality of fins are located between it and the base; a first side wall portion that closes the space between the base and the ends of the opposing wall portion at one end in the direction of arrangement of the plurality of fins; and a second side wall portion that closes the space between the base and the ends of the opposing wall portion at the other end in the direction of arrangement. Within the cylindrical body formed by the base and the cover, the gaps between adjacent fins are used as fluid passages. A motor drive device wherein at least one of the base or the opposing wall portion has a communication port that connects the flow path to the outside of the cylindrical body. 　 The motor drive device according to claim 1, wherein the communication port is opened in at least one of the base or the opposing wall portion so as to open a part of the arrangement direction. 　 The motor drive device according to claim 1, wherein the communication ports are arranged in a plurality in the direction of arrangement. 　 The motor drive device according to claim 3, wherein the plurality of communication ports have different lengths in the direction of arrangement. 　 The motor drive device according to any one of claims 1 to 4, wherein the communication ports are arranged in a plurality in a direction perpendicular to the arrangement direction. 　 The motor drive device according to claim 5, wherein the plurality of communication ports, which are arranged in a direction perpendicular to the arrangement direction, are offset from each other in the arrangement direction. 　 The opposing wall portion consists of a plurality of wall materials arranged in a direction perpendicular to the arrangement direction, The plurality of wall materials are movable in a direction perpendicular to the arrangement direction with respect to the first side wall portion and the second side wall portion. The motor drive device according to any one of claims 1 to 6, wherein the communication opening is the gap between adjacent wall materials. 　 The first side wall portion and the second side wall portion have rails extending in a direction perpendicular to the arrangement direction, The motor drive device according to claim 7, wherein the plurality of wall materials are provided on the rail so as to be slidable in a direction perpendicular to the arrangement direction. 　 The motor drive device according to any one of claims 1 to 8, wherein the heat sink further comprises an adjustment mechanism that can change the direction of fluid flow through the communication port. 　 The power modules are provided in multiple locations on the first surface along the direction in which the flow path extends, The motor drive device according to any one of claims 1 to 9, wherein the communication port is located upstream of the flow path, among the adjacent power modules, of which the power module located downstream of the flow path is located upstream of the flow path. 　 The power module has a plurality of heat-generating elements arranged along the direction in which the flow path extends, The motor drive device according to claim 1, wherein the communication port is located upstream of the flow path, among the adjacent heat-generating components, of which the heat-generating component is located downstream of the flow path.

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