Cooler and power converter

Abstract

The present invention provides a cooler and a power converter that suppress the occurrence of distortion. [Solution] The case 600 has a first case 610 and a second case 620. The first case has a first outer surface 610a and a first inner surface 610b aligned in the Z direction. The second case has a second outer surface 620a and a second inner surface 620b aligned in the Z direction. The second inner surface and the first inner surface face each other in the Z direction to form a refrigerant passage 600a. The first case has a main part 630, an assembly part 640 and a reinforcing part 650. The switch case 550 is pressed against the first outer surface of the main part by a pressing member 700. The assembly part is annular in the circumferential direction around the Z direction and is assembled to the second case. The reinforcing part is annular in the circumferential direction and is located between the main part and the assembly part in a plane direction perpendicular to the Z direction, connecting the two. The reinforcing part is longer in the Z direction than the main part and shorter in the Z direction than the assembly part.

Description

Technical Field

[0001] The disclosure described in this specification relates to a cooler and a power conversion device.

Background Art

[0002] Patent Document 1 discloses a liquid-cooled cooling device provided with a heating element.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration described in Patent Document 1, it is conceivable to efficiently cool the heating element by reducing the thermal resistance between the heating element and the liquid-cooled cooling device. For example, it is conceivable to reduce the thermal resistance between the two by pressing and fixing the heating element to the liquid-cooled cooling device. However, in the case of such a configuration, there is a risk that the liquid-cooled cooling device may be distorted due to the pressing and fixing of the heating element to the liquid-cooled cooling device.

[0005] An object of the present disclosure is to provide a cooler and a power conversion device in which distortion is suppressed from occurring.

Means for Solving the Problems

[0006] The cooler of the disclosed aspect is a cooler (600) in which electrical components (521, 550) included in a power conversion circuit (500) are pressed in a first direction by a pressing member (700), a first case (610) having a first outer surface (610a) and a first inner surface (610b) arranged in the first direction, and the electrical component is pressed against the first outer surface, The present invention comprises a second case (620) having a second outer surface (620a) and a second inner surface (620b) aligned in a first direction, wherein the second inner surface is located on the first inner surface side in the first direction compared to the second outer surface, and the second inner surface faces the first inner surface at a distance in the first direction, thereby forming a refrigerant passage (600a) through which the refrigerant flows together with the first case, The first case is, The main part (630) against which the electrical components are pressed by the pressing member, An assembly part (640) that forms an annular shape in the circumferential direction around the first direction and is assembled to the second case, It has a reinforcing portion (650) that forms an annular shape in the circumferential direction, is located between the main portion and the assembly portion in a planar direction perpendicular to the first direction, and connects the main portion and the assembly portion. The reinforcing section is longer in the first direction than the main section, and shorter in the first direction than the assembly section.

[0007] The power converter in the disclosed embodiment is The electrical components (521, 550) included in the power conversion circuit (500), A cooler (600) on which electrical components are installed, A power conversion device having a pressing member (700) for pressing and fixing electrical components to a cooler in a first direction, The cooler is, A first case (610) having a first outer surface (610a) and a first inner surface (610b) aligned in a first direction, with an electrical component pressed against the first outer surface, The present invention comprises a second case (620) having a second outer surface (620a) and a second inner surface (620b) aligned in a first direction, wherein the second inner surface is located on the first inner surface side in the first direction compared to the second outer surface, and the second inner surface faces the first inner surface at a distance in the first direction, thereby forming a refrigerant passage (600a) through which the refrigerant flows together with the first case, The first case is, The main part (630) against which the electrical components are pressed by the pressing member, An assembly part (640) that forms an annular shape in the circumferential direction around the first direction and is assembled to the second case, It has a reinforcing portion (650) that forms an annular shape in the circumferential direction, is located between the main portion and the assembly portion in a planar direction perpendicular to the first direction, and connects the main portion and the assembly portion. The reinforcing section is longer in the first direction than the main section, and shorter in the first direction than the assembly section.

[0008] According to this, the pressing of the electrical components (521, 550) against the first case (610) by the pressing member (700) suppresses distortion in the first case (610). Distortion in the cooler (600) is also suppressed.

[0009] The reference numbers in parentheses above merely indicate the correspondence with the configurations described in the embodiments below, and do not limit the technical scope in any way. [Brief explanation of the drawing]

[0010] [Figure 1] This is a circuit diagram used to explain an in-vehicle system. [Figure 2] This is a top view of a power converter. [Figure 3] This is a top view of the power converter with the fixed components removed from Figure 2. [Figure 4] This is a top view of the power converter with the spring body removed from Figure 3. [Figure 5] This is a top view of the power converter, with the switch case removed from Figure 4. [Figure 6] This is a top view of the power converter, with the first case removed from Figure 5. [Figure 7] This is a cross-sectional view of the power converter along the VII-VII line shown in Figure 2. [Figure 8] Figure 2 shows a cross-sectional view of the power converter along the VIII-VIII line. [Figure 9] This is a top view of Case 1. [Figure 10] This is a bottom view of the first case. [Figure 11] This is a side view of the first case. [Figure 12]It is a side view of the first case. [Figure 13] It is a cross-sectional view showing a comparative example of a power conversion device. [Figure 14] It is an enlarged cross-sectional view of a power conversion device. [Figure 15] It is an enlarged cross-sectional view of a power conversion device. [Figure 16] It is an enlarged cross-sectional view of a power conversion device. [Figure 17] It is an enlarged cross-sectional view of a power conversion device. [Figure 18] It is an enlarged cross-sectional view of a power conversion device. [Figure 19] It is a cross-sectional view of a power conversion device. [Figure 20] It is an enlarged cross-sectional view of a power conversion device.

Mode for Carrying Out the Invention

[0011] Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. Parts corresponding to those described in the previous mode may be denoted by the same reference numerals in the subsequent mode, and duplicate descriptions may be omitted. When only a part of the configuration is described in each mode, the description of the other part of the configuration can be applied to the previous mode.

[0012] Combinations are possible between parts that are explicitly shown to be combinable in each mode. Also, unless there is a problem with the combination, combinations are possible between a plurality of modes, a mode and a modification example, and between a plurality of modification examples, even if not explicitly shown to be combinable.

[0013] Hereinafter, three directions that are orthogonal to each other are shown as the X direction, the Y direction, and the Z direction. The X direction, the Y direction, and the Z direction are linear directions. In the drawings, the description of "direction" is omitted, and only X, Y, and Z are illustrated.

[0014] When this disclosure is mounted on a vehicle, the X direction is aligned with the left-right direction of the vehicle. The Y direction is aligned with the vehicle's forward and backward direction. The Z direction is aligned with the vehicle's up-down direction. When the vehicle is stationary on a horizontal plane, the plane defined by the X and Y directions is aligned with the horizontal direction. The Z direction is aligned with the vertical direction. Hereinafter, embodiments will be described assuming that the plane defined by the X and Y directions is aligned with the horizontal direction and the Z direction is aligned with the vertical direction. The X direction corresponds to the second direction. The Y direction corresponds to the third direction. The Z direction corresponds to the first direction.

[0015] <First Embodiment> <In-vehicle systems> First, based on Figure 1, we will outline the in-vehicle system 100 to which the power converter 300 is applied. This in-vehicle system 100 constitutes a system for an electric vehicle. The in-vehicle system 100 includes a battery 200, a power converter 300, and a motor 400.

[0016] Furthermore, the in-vehicle system 100 has multiple ECUs (not shown). These multiple ECUs transmit and receive signals to each other via bus wiring. The multiple ECUs cooperate to control the electric vehicle. The powering and regeneration of the motor 400 are controlled according to the State of Charge (SOC) of the battery 200 by the control of the multiple ECUs. ECU stands for electronic control unit. SOC stands for state of charge.

[0017] An ECU comprises at least one arithmetic processing unit (CPU) and at least one memory device (MMR) as a recording medium for recording programs and data. The ECU is provided by a microcomputer equipped with a computer-readable recording medium. The recording medium is a non-transitional tangible recording medium that non-temporarily stores computer-readable programs. The recording medium may be provided by semiconductor memory or a magnetic disk, etc.

[0018] Battery 200 has multiple secondary batteries. These secondary batteries form a battery stack connected in series. The state of charge (SOC) of this battery stack corresponds to the state of charge (SOC) of battery 200. As secondary batteries, solid-state batteries, lithium-ion secondary batteries, nickel-metal hydride secondary batteries, and organic radical batteries can be used.

[0019] The power converter 300 performs power conversion between the battery 200 and the motor 400. The power converter 300 converts the DC power from the battery 200 into AC power. The power converter 300 converts the AC power generated by the motor 400's power generation (regeneration) into DC power.

[0020] Motor 400 is connected to the axle of an electric vehicle (not shown). The rotational energy (power) of motor 400 is transmitted to the wheels of the electric vehicle via the axle. Conversely, the rotational energy of the wheels is transmitted to motor 400 via the axle.

[0021] The motor 400 is powered by alternating current (AC) electricity supplied from the power converter 300. This provides propulsion to the wheels. The motor 400 also regenerates energy from the rotational energy transmitted from the wheels. The AC electricity generated by this regeneration is converted into DC electricity by the power converter 300. This DC electricity is supplied to the battery 200 and various electrical loads installed in the electric vehicle.

[0022] <Power converter> Next, the power converter 300 will be described. The power converter 300 has a power conversion circuit 500 and a case 600.

[0023] The components of the power conversion circuit 500 are housed in the case 600. As schematically shown in Figure 7, the case 600 is equipped with a refrigerant passage 600a through which the refrigerant flows. The refrigerant flowing through this refrigerant passage 600a suppresses the temperature rise of the power conversion circuit 500. In the drawing, the direction of refrigerant flow is indicated by a white arrow.

[0024] <Power Conversion Circuit> The power conversion circuit 500 includes an inverter 510. The inverter 510 converts the DC power from the battery 200 into AC power. This AC power is supplied to the motor 400. The inverter 510 also converts the AC power generated by the motor 400 into DC power. This DC power is supplied to the battery 200. The power conversion circuit 500 may also include a converter that boosts or lowers the input voltage before outputting it.

[0025] The power conversion circuit 500 has an N busbar 501 and a P busbar 502. The battery 200 is connected to these N busbars 501 and P busbars 502. The N busbar 501 is connected to the negative terminal of the battery 200. The P busbar 502 is connected to the positive terminal of the battery 200.

[0026] Furthermore, the power conversion circuit 500 has a U-phase busbar 503, a V-phase busbar 504, and a W-phase busbar 505. The inverter 510 and the motor 400 are electrically connected via these U-phase busbars 503, V-phase busbars 504, and W-phase busbars 505. In Figure 1, the connection points of the various busbars are indicated by white circles. These connection points are electrically connected, for example, by bolts or welding.

[0027] <Inverter> The inverter 510 has a smoothing capacitor 520 and a switch group 530. The N busbar 501 and the P busbar 502 are electrically connected to the smoothing capacitor 520 and the switch group 530.

[0028] The smoothing capacitor 520 is housed in a capacitor case 521. The capacitor case 521 is made of an insulating resin material. Parts of the N busbar 501 and the P busbar 502 are housed in the capacitor case 521. This capacitor case 521 is fixed to the case 600.

[0029] The switch group 530 comprises a U-phase switch module 531, a V-phase switch module 532, and a W-phase switch module 533. These three-phase switch modules have a high-side switch 541 and a low-side switch 542. The three-phase switch modules also have a high-side diode 541a and a low-side diode 542a.

[0030] The switches and diodes of the three-phase switch module are housed in a switch case 550. The switch case 550 is made of an insulating resin material. In this embodiment, the switches and diodes of the three-phase switch module are individually housed in three switch cases 550. Of course, it is also possible to adopt a configuration in which the switches and diodes of the three-phase switch module are housed in a single switch case 550.

[0031] In this embodiment, n-channel IGBTs are used as the high-side switch 541 and the low-side switch 542. As shown in Figure 1, the emitter electrode of the high-side switch 541 and the collector electrode of the low-side switch 542 are connected. This connects the high-side switch 541 and the low-side switch 542 in series.

[0032] Furthermore, the cathode electrode of the high-side diode 541a is connected to the collector electrode of the high-side switch 541. The anode electrode of the high-side diode 541a is connected to the emitter electrode of the high-side switch 541. As a result, the high-side diode 541a is connected in antiparallel to the high-side switch 541.

[0033] Similarly, the cathode electrode of the low-side diode 542a is connected to the collector electrode of the low-side switch 542. The anode electrode of the low-side diode 542a is connected to the emitter electrode of the low-side switch 542. As a result, the low-side diode 542a is connected in antiparallel to the low-side switch 542.

[0034] As described above, the switch is housed in the switch case 550. From this switch case 550, the tip of the collector terminal 540a, which is connected to the collector electrode of the high-side switch 541, and the tip of the output terminal 540b, which is connected to the midpoint between the high-side switch 541 and the low-side switch 542, are exposed. Also, from the switch case 550, the tip of the emitter terminal 540c, which is connected to the emitter electrode of the low-side switch 542, and the tip of the gate terminal 540d, which is connected to the gate electrodes of the high-side switch 541 and the low-side switch 542, are exposed.

[0035] As shown in Figure 1, the collector terminal 540a is connected to the P busbar 502. The emitter terminal 540c is connected to the N busbar 501. Due to these electrical connections, the high-side switch 541 and the low-side switch 542 are connected in series sequentially from the P busbar 502 to the N busbar 501.

[0036] The U-phase busbar 503 is connected to the output terminal 540b of the U-phase switch module 531. The V-phase busbar 504 is connected to the output terminal 540b of the V-phase switch module 532. The W-phase busbar 505 is connected to the output terminal 540b of the W-phase switch module 533.

[0037] Motor 400 has a U-phase stator coil, a V-phase stator coil, and a W-phase stator coil. A U-phase busbar 503 is electrically connected to the U-phase stator coil. A V-phase busbar 504 is electrically connected to the V-phase stator coil. A W-phase busbar 505 is electrically connected to the W-phase stator coil. This electrically connects the inverter 510 and the motor 400.

[0038] The gate terminals 540d of the high-side switch 541 and low-side switch 542 included in the U-phase switch modules 531 to W-phase switch modules 533 are connected to the gate driver.

[0039] The gate driver, along with some of the ECUs mentioned above, is included in the circuit board 560 shown in Figure 1. The ECU generates a control signal and outputs it to the gate driver. The gate driver amplifies the control signal and outputs it to the gate terminal 540d. As a result, the high-side switch 541 and the low-side switch 542 are opened and closed by the ECU. Note that the board on which the gate driver is mounted and the board on which the ECU is mounted may be separate.

[0040] The ECU generates pulse signals as control signals. The ECU adjusts the duty cycle and frequency of these pulse signals. These duty cycle and frequency are determined based on the outputs of various sensors, etc.

[0041] When motor 400 is operating, the high-side switch 541 and low-side switch 542 of the three-phase switch module are PWM controlled by the output of a control signal from the ECU. This generates a three-phase alternating current in the power conversion circuit 500. This three-phase alternating current is input to the three phase stator coils. This generates a three-phase rotating magnetic field in the three phase stator coils. The interaction between this three-phase rotating magnetic field and the magnetic field generated from the rotor of motor 400 generates rotational torque in the rotor.

[0042] When the motor 400 generates electricity (regenerates) due to the rotational energy of the driving wheels, the ECU, for example, stops outputting the control signal. As a result, the AC power generated by the regeneration passes through the diodes of the three-phase switch module. Consequently, the AC power is converted to DC power.

[0043] Furthermore, the type of switch element provided in the U-phase switch modules 531 to W-phase switch modules 533 is not particularly limited; for example, MOSFETs can be used. The semiconductor elements such as switches and diodes included in these three-phase switch modules can be manufactured from semiconductors such as Si and wide-bandgap semiconductors such as SiC. The constituent materials of the semiconductor elements are not particularly limited.

[0044] Furthermore, the number of high-side switches 541 and low-side switches 542 in a three-phase switch module is not limited to one. At least one of the three-phase switch modules may have multiple high-side switches 541 connected in parallel. At least one of the three-phase switch modules may have multiple low-side switches 542 connected in parallel. The number of switches connected in parallel can be determined based on the rated current of the switches and the amount of current that can be energized by the power conversion circuit 500.

[0045] <Case> Case 600 is made of a high-permeability material with higher magnetic permeability than air. Specifically, case 600 is made of a metal material such as aluminum or iron. The capacitor case 521 and the switch case 550 are housed in case 600. The components of the power conversion circuit 500 shown in Figure 1 are housed in case 600. In addition, current sensors and other components not shown are also housed in case 600.

[0046] Case 600 has multiple case members. These are connected via sealing material, forming a refrigerant passage 600a inside case 600. An input pipe and a discharge pipe are connected to this refrigerant passage 600a. These input and discharge pipes are connected to a pump. The refrigerant flowing into the refrigerant passage from the input pipe exchanges heat with the components of the power conversion circuit 500 housed in case 600. This heat-exchanged refrigerant is returned to the pump via the discharge pipe. The temperature of the refrigerant returned to the pump is lowered by a cooling device such as a radiator. This cooled refrigerant is then supplied back to the input pipe. Case 600 acts as a cooler.

[0047] The condenser case 521 is positioned opposite the upstream side of the refrigerant passage 600a. The switch case 550 is positioned opposite the downstream side of the refrigerant passage 600a. The condenser case 521 and the switch case 550 are pressed and fixed to the case 600. Therefore, the condenser case 521 and the switch case 550 are capable of actively conducting heat to the case 600.

[0048] Due to the configuration described above, the temperature rise of the smoothing capacitor 520 housed in the capacitor case 521 is suppressed mainly by the refrigerant passing upstream of the refrigerant passage 600a. The temperature rise of the switch group 530 housed in the switch case 550 is suppressed mainly by the refrigerant passing downstream of the refrigerant passage 600a.

[0049] In this embodiment, the elements constituting the refrigerant passage 600a that cools the switch case 550 will be described from among the case members described above. The case 600 has a first case 610 and a second case 620 as such case members.

[0050] For example, as shown in Figure 7, the first case 610 and the second case 620 are aligned in the Z direction. The first case 610 has a first outer surface 610a and a first inner surface 610b aligned in the Z direction. The second case 620 has a second outer surface 620a and a second inner surface 620b aligned in the Z direction.

[0051] The first inner surface 610b is located closer to the second case 620 in the Z direction than the first outer surface 610a. The second inner surface 620b is located closer to the first case 610 in the Z direction than the second outer surface 620a.

[0052] The first inner surface 610b and the second inner surface 620b are aligned in the Z direction, separated by a sealing material (not shown). A portion of the first inner surface 610b and a portion of the second inner surface 620b are separated in the Z direction. A refrigerant passage 600a is formed between the first inner surface 610b and the second inner surface 620b.

[0053] The second case 620 has multiple through holes that penetrate the second outer surface 620a and the second inner surface 620b. The refrigerant passes through these multiple through holes. One of the multiple through holes functions as an inlet hole 670 through which the refrigerant flows into the refrigerant passage 600a. Another of the multiple through holes functions as an outlet hole 680 through which the refrigerant is discharged from the refrigerant passage 600a.

[0054] The inlet hole 670 and the outlet hole 680 are separated in the X direction. Therefore, the refrigerant that flows from the inlet hole 670 into the refrigerant passage 600a mainly flows along the X direction toward the outlet hole 680. This refrigerant flowing in the X direction flows into the outlet hole 680. This refrigerant is then discharged from the refrigerant passage 600a through the outlet hole 680.

[0055] Naturally, the direction of refrigerant flow within the refrigerant passage 600a depends on the structure of the refrigerant passage 600a. The refrigerant may generate turbulence within the refrigerant passage 600a. The direction of refrigerant flow is not uniformly in the X direction. Also, the flow velocity of the refrigerant is not uniform within the refrigerant passage 600a.

[0056] <Switch Case> As described above, the three-phase switch module includes a high-side switch 541 and a low-side switch 542, and high-side diodes 541a and low-side diodes 542a. The switches and diodes of this three-phase switch module are individually housed in three switch cases 550. These three switch cases 550 have upper surfaces 550a and lower surfaces 550b aligned in the Z direction.

[0057] As shown in Figure 7, the three switch cases 550 are provided on the first outer surface 610a of the first case 610. The lower surface 550b is located closer to the first outer surface 610a in the Z direction than the upper surface 550a. As shown in Figures 3 and 4, these three switch cases 550 are aligned in the X direction.

[0058] As shown in Figures 4 and 8, the high-side switch 541 and low-side switch 542 housed in the switch case 550 are aligned in the Y direction. Although not shown, the high-side diode 541a and low-side diode 542a housed in the switch case 550 are also aligned in the Y direction.

[0059] The high-side switch 541 and the low-side switch 542 are active elements and heat-generating elements. These two heat-generating elements are housed within the switch case 550. These two heat-generating elements are aligned in the Y direction. As mentioned above, the three switch cases 550 are aligned in the X direction. Therefore, if we consider the X direction as the row direction and the Y direction as the column direction, as shown by the dashed lines in Figure 4, there are three heat-generating elements in the row direction and two in the column direction. A total of six heat-generating elements arranged in this matrix are aligned with the refrigerant passage 600a in the Z direction.

[0060] <Pressing component> As described above, the switch case 550 is pressed and fixed to the case 600. To realize this configuration, the power converter 300 has a pressing member 700 in addition to the power conversion circuit 500 and the case 600.

[0061] The pressing member 700 has a fixed body 710 and a spring body 720. The fixed body 710 and the spring body 720 have a flattened shape with a thin thickness in the Z direction. The fixed body 710 has higher rigidity than the spring body 720. In the drawings, the fixed body 710 and the spring body 720 are shown as rectangular parallelepipeds, but their shapes are not particularly limited. Their shapes are simplified in the drawings.

[0062] As shown in Figures 2 to 8, the fixed body 710, spring body 720, switch case 550, first case 610, and second case 620 are stacked in order in the Z direction. The spring body 720, switch case 550, and first case 610 are all located in the projection area of ​​the fixed body 710 onto the second case 620 along the Z direction.

[0063] The fixed body 710 is fixed to the second case 620 by the fixing member 730 in such a manner that it approaches the case 600 in the Z direction. Due to this fixing, a force acts from the fixed body 710 toward the second case 620 in the direction indicated by the black arrows in Figures 7 and 8. This force acts on the spring body 720, the switch case 550, and the first case 610, which are located between the fixed body 710 and the second case 620. Between the fixed body 710 and the second case 620, the spring body 720, the switch case 550, and the first case 610 are compressed in the Z direction. The fixing member 730 is a bolt, rivet, etc.

[0064] The spring body 720 is fixed to the fixed body 710 by a fixing member (not shown) in such a manner that it approaches the fixed body 710 in the Z direction. In this way, the spring body 720 is connected to the fixed body 710. The spring body 720 is supported by the highly rigid fixed body 710.

[0065] The spring body 720 has a spring portion that elastically deforms in the Z direction. Compression in the Z direction by the aforementioned fixing member 730 generates a restoring force (applied pressure) from the spring portion along the Z direction.

[0066] An isobaric sheet may be interposed between the spring body 720 and the switch case 550. In this configuration, the isobaric sheet is compressed between the spring body 720 and the switch case 550. The spring body 720 and the switch case 550 are aligned in the Z direction via the isobaric sheet.

[0067] The restoring force generated by the spring body 720 acts on the switch case 550 via the isobaric sheet. The isobaric sheet equalizes the restoring force acting from the spring body 720 to the switch case 550. This suppresses unevenness in the contact state between the switch case 550 and the first case 610 depending on the location. It also suppresses significant differences in thermal conductivity between the switch case 550 and the first case 610 depending on the location.

[0068] <Case 1> As shown in Figures 9 to 12, the first case 610 has a flattened shape with a thin thickness in the Z direction. As described above, the first case 610 has a first outer surface 610a and a first inner surface 610b aligned in the Z direction. The position of the first outer surface 610a in the Z direction is constant, but the position of the first inner surface 610b in the Z direction varies depending on the location. In addition to these first outer surface 610a and first inner surface 610b, the first case 610 also has a side surface 610c that connects them.

[0069] To explain the structure by function, the first case 610 has a main section 630, an assembly section 640, and a reinforcing section 650. The main section 630 is connected to the assembly section 640 via the reinforcing section 650. In Figures 5 and 9, dashed lines are shown at the boundary between the main section 630 and the reinforcing section 650, and at the boundary between the reinforcing section 650 and the assembly section 640. In the cross-sectional view, dashed lines are also shown at the above boundaries.

[0070] The main part 630 is larger in size than the assembly part 640 and the reinforcing part 650 in a plane perpendicular to the Z direction. The planar shape of the main part 630 is rectangular. A switch case 550 is provided on the first outer surface 610a of the main part 630. The switch case 550 is pressed against the main part 630 by the pressing member 700.

[0071] The assembly portion 640 is annular in the circumferential direction around the Z direction. The assembly portion 640 has a side surface 610c. The assembly portion 640 is longer in the Z direction than the main portion 630. Therefore, the assembly portion 640 has higher rigidity in the Z direction than the main portion 630. The assembly portion 640 is assembled to the second case 620.

[0072] The reinforcing portion 650 forms an annular shape in the circumferential direction around the Z direction. The reinforcing portion 650 is located between the main portion 630 and the assembly portion 640 in a planar direction perpendicular to the Z direction. The reinforcing portion 650 integrally connects the main portion 630 and the assembly portion 640.

[0073] Hereafter, the circumferential direction around the Z direction will be simply referred to as the circumferential direction. The planar direction perpendicular to the Z direction will be simply referred to as the planar direction. The X and Y directions are aligned with the planar direction.

[0074] The length of the reinforcing portion 650 in the Z direction is longer than the length of the main portion 630 in the Z direction, but shorter than the length of the assembly portion 640 in the Z direction. As a result, the reinforcing portion 650 has higher rigidity in the Z direction than the main portion 630, but lower rigidity in the Z direction than the assembly portion 640.

[0075] As shown in Figure 14, the first inner surface 610b of the main part 630 is located on the first outer surface 610a side in the Z direction compared to the first inner surface 610b of the assembly part 640. The first inner surface 610b of the reinforcing part 650 extends from the first inner surface 610b of the main part 630 toward the first inner surface 610b of the assembly part 640. As a result, the first inner surface 610b of the reinforcing part 650 is inclined with respect to the Z direction. The first outer surface 610a of the reinforcing part 650 is perpendicular to the Z direction, but its first inner surface 610b is inclined with respect to the Z direction in such a manner that the length of the reinforcing part 650 in the Z direction increases in the surface direction as it moves from the main part 630 toward the assembly part 640. The length of the reinforcing part 650 in the Z direction is the separation distance between the first outer surface 610a and the first inner surface 610b in the Z direction.

[0076] Figure 14 shows a dashed line VL connecting the boundary between the reinforcing portion 650 and the main portion 630 on the first inner surface 610b, and the boundary between the reinforcing portion 650 and the assembly portion 640 on the first inner surface 610b. The first inner surface 610b of the reinforcing portion 650 has irregularities, but the inclination angle with respect to the Z direction of the first inner surface 610b after averaging and smoothing these irregularities is equivalent to the inclination angle with respect to the Z direction of the virtual line VL.

[0077] Furthermore, the boundary between the reinforcing portion 650 and the main portion 630 on the first inner surface 610b can be determined based on the difference in length (thickness) in the Z direction between the reinforcing portion 650 and the main portion 630. The boundary between the reinforcing portion 650 and the assembly portion 640 can be determined by the difference in length (thickness) in the Z direction between the reinforcing portion 650 and the assembly portion 640.

[0078] The intersection point II of this virtual straight line VL with the first outer surface 610a is indicated by a black dot in the drawing. This intersection point II is located on the first outer surface 610a of the main part 630. In the plane direction, this intersection point II is located on the assembly part 640 side of the placement location of the switch case 550 on the first outer surface 610a.

[0079] Furthermore, intersection position II may be located at the placement location of the switch case 550 on the first outer surface 610a. In this case, intersection position II is preferably located on the assembly portion 640 side of the location of the switch (heating element) housing in the switch case 550 on the first outer surface 610a in the planar direction.

[0080] <Case 2> As shown in Figures 6 and 7, the separation distance between the second outer surface 620a and the second inner surface 620b of the second case 620 varies depending on the location. The position of the second outer surface 620a in the Z direction remains constant, but the position of the second inner surface 620b in the Z direction changes depending on the location.

[0081] To explain separately according to their position and shape, as shown in Figures 6 to 8, the second inner surface 620b has a first bottom surface 621, a first annular surface 622, a second bottom surface 623, a second annular surface 624, and an outer inner surface 625.

[0082] The first bottom surface 621 has a larger area of ​​planes perpendicular to the Z direction than the first annular surface 622, the second bottom surface 623, the second annular surface 624, and the outer inner surface 625. The first bottom surface 621 is located closer to the second outer surface 620a in the Z direction than these four surfaces. An inlet hole 670 and an outlet hole 680 are opened in the first bottom surface 621.

[0083] The first bottom surface 621 faces the first inner surface 610b of the main part 630 and the reinforcing part 650 while being separated in the Z direction. The openings of the inlet hole 670 and the discharge hole 680 on the first bottom surface 621 side face the first inner surface 610b of the main part 630 and the reinforcing part 650 while being separated in the Z direction.

[0084] The first bottom surface 621 may also face a part of the first inner surface 610b of the assembly portion 640 while being separated in the Z direction. The openings of the inlet hole 670 and the discharge hole 680 on the first bottom surface 621 side face the first inner surface 610b of the assembly portion 640 while being separated in the Z direction.

[0085] The first annular surface 622 is located between the first base surface 621 and the second base surface 623 in the Z direction. The first annular surface 622 rises from the first base surface 621 in the Z direction in such a manner that it is separated from the second outer surface 620a. The first annular surface 622 is annular in the circumferential direction. The first annular surface 622 surrounds the first base surface 621.

[0086] As shown in Figure 6, the first annular surface 622 has a first section screen 622a and a second section screen 622b aligned in the X direction, and a third section screen 622c and a fourth section screen 622d aligned in the Y direction. In the X direction, the inlet hole 670 is located on the first section screen 622a side of the second section screen 622b. In the X direction, the discharge hole 680 is located on the second section screen 622b side of the first section screen 622a.

[0087] The Y-direction position of the geometric centers of the inlet hole 670 and the outlet hole 680 is midway between the third section screen 622c and the fourth section screen 622d. At least a portion of the inlet hole 670 may open into the first section screen 622a. At least a portion of the outlet hole 680 may open into the second section screen 622b.

[0088] The second base surface 623 is further away from the second outer surface 620a in the Z direction than the first base surface 621. The second base surface 623 is connected to the first base surface 621 via the first annular surface 622. The second base surface 623 is located between the first annular surface 622 and the second annular surface 624 in the Z direction.

[0089] The second base surface 623 is annular in the circumferential direction. The second base surface 623 surrounds the first base surface 621 and the first annular surface 622. As shown in Figure 6, the second base surface 623 has a first connecting surface 623a and a second connecting surface 623b aligned in the X direction, and a third connecting surface 623c and a fourth connecting surface 623d aligned in the Y direction.

[0090] The four connecting surfaces of the second bottom surface 623 and the first inner surface 610b of the assembly part 640 are arranged opposite each other in the Z direction. A sealing material is provided between the second bottom surface 623 and the first inner surface 610b of the assembly part 640. The sealing material is compressed by the force along the Z direction from the fixing member 730 and the spring part described above. As a result, the refrigerant passage 600a is sealed. The refrigerant passage 600a is partitioned by the main part 630, the first inner surface 610b of the reinforcing part 650, the first bottom surface 621, and the first annular surface 622.

[0091] Furthermore, a recess for providing a sealing material may be formed on at least one of the second bottom surface 623 side of the second case 620 and the first inner surface 610b side of the assembly portion 640. On the second bottom surface 623 side of the second case 620 and the first inner surface 610b side of the assembly portion 640, irregularities may be formed to extend the length in the surface direction of the gap between the second bottom surface 623 and the first inner surface 610b of the assembly portion 640.

[0092] The second annular surface 624 is located in the Z direction between the second base surface 623 and the outer inner surface 625. The second annular surface 624 rises from the second base surface 623 in the Z direction in a manner that separates it from the second outer surface 620a. The second base surface 623 and the outer inner surface 625 are connected via the second annular surface 624. The second annular surface 624 is annular in the circumferential direction. The second annular surface 624 surrounds the second base surface 623, the first annular surface 622, and the first base surface 621.

[0093] As shown in Figure 6, the second annular surface 624 has a fifth connecting surface 624a and a sixth connecting surface 624b aligned in the X direction, and a seventh connecting surface 624c and an eighth connecting surface 624d aligned in the Y direction. These four connecting surfaces of the second annular surface 624 and the side surface 610c of the assembly portion 640 are arranged opposite each other in the surface direction.

[0094] A sealing material may be provided between the second annular surface 624 and the side surface 610c of the assembly portion 640. A recess for providing the sealing material may be formed on at least one of the sides of the second case 620 (the side with the second annular surface 624) and the side surface 610c of the assembly portion 640.

[0095] <Heat dissipation pin> Heat dissipation pins 690 for actively exchanging heat with the refrigerant are formed on the first inner surface 610b of the first case 610. In this embodiment, the heat dissipation pins 690 are formed on the first inner surface 610b of the main part 630 and the reinforcing part 650.

[0096] The heat dissipation pin 690 extends from the first inner surface 610b of the main part 630 along the Z direction toward the first bottom surface 621. The heat dissipation pin 690 also extends from the first inner surface 610b of the reinforcing part 650 along the Z direction toward the first bottom surface 621.

[0097] As described above, the first inner surface 610b of the reinforcing portion 650 is inclined from the first inner surface 610b of the main portion 630 toward the first inner surface 610b of the assembly portion 640. Therefore, the first inner surface 610b of the reinforcing portion 650 is located on the first bottom surface 621 side in the Z direction compared to the first inner surface 610b of the main portion 630.

[0098] Due to this configuration, the root position of the heat dissipation pin 690 formed on the first inner surface 610b of the reinforcing portion 650 is located closer to the first bottom surface 621 in the Z direction than the root position of the heat dissipation pin 690 formed on the first inner surface 610b of the main portion 630. However, the tip positions in the Z direction of these multiple heat dissipation pins 690 with different root positions are the same. Therefore, the length in the Z direction of the heat dissipation pin 690 formed on the reinforcing portion 650 is shorter than the length in the Z direction of the heat dissipation pin 690 formed on the main portion 630.

[0099] As shown in Figure 14, the Z-direction separation distance between the formation location of the heat dissipation pin 690 on the first inner surface 610b of the reinforcing portion 650 and the first outer surface 610a is the first length L1. The Z-direction length of the location where the heat dissipation pin 690 is formed on the reinforcing portion 650 is the first length L1. The Z-direction length of the heat dissipation pin 690 formed on the first inner surface 610b of the reinforcing portion 650 is the second length L2. The first length L1 is longer than the second length L2. Thus, the Z-direction length of the location where the heat dissipation pin 690 is formed on the reinforcing portion 650 is longer than the length of the heat dissipation pin 690 formed on the reinforcing portion 650.

[0100] The tips of the multiple heat dissipation pins 690 are spaced apart from the first bottom surface 621 in the Z direction. The distance between the tips of the heat dissipation pins 690 and the first bottom surface 621 is longer than the length of the heat dissipation pins 690 formed on the main part 630 in the Z direction. This creates a space between the tips of the heat dissipation pins 690 and the first bottom surface 621 for the coolant to pass through. However, the distance between the tips of the heat dissipation pins 690 and the first bottom surface 621 may be less than or equal to the length of the heat dissipation pins 690 formed on the main part 630 in the Z direction.

[0101] As shown in Figure 10, the shape of the heat dissipation pin 690 in a plane perpendicular to the Z direction is elliptical. The major axis of the heat dissipation pin 690 is along the X direction, and the minor axis is along the Y direction. Multiple heat dissipation pins 690 are arranged in both the X and Y directions. In this embodiment, the formation density of the multiple heat dissipation pins 690 is constant.

[0102] <Comparative Example> Figure 13 shows an example in which the first case 610 has only a main part 630 and an assembly part 640. The main part 630 and the assembly part 640 are directly connected. In this configuration, when the switch case 550 is pressed against the first case 610 by the pressing member 700, stress concentration occurs in the area enclosed by the dashed line in Figure 13. Stress concentration occurs on the assembly part 640 side of the main part 630. As a result, there is a risk that the first case 610 will be distorted.

[0103] <Effects of this disclosure> In contrast, in this disclosure, the main part 630 and the assembly part 640 are connected via a reinforcing part 650. The reinforcing part 650 has a longer length in the Z direction than the main part 630. The reinforcing part 650 has a shorter length in the Z direction than the assembly part 640.

[0104] According to this, when the switch case 550 is pressed against the first case 610 by the pressing member 700, stress concentration is more likely to occur in the reinforcing part 650 than in the main part 630. Therefore, the pressing of the switch case 550 against the first case 610 by the pressing member 700 suppresses distortion in the first case 610. Distortion in the case 600 is also suppressed.

[0105] Multiple heat dissipation pins 690 are formed on the first inner surface 610b side of the main portion 630 and on the first inner surface 610b side of the reinforcing portion 650.

[0106] According to this, not only is the heat exchange between the main part 630, where the switch case 550 is provided, and the refrigerant improved, but the heat exchange between the reinforcing part 650 located around the main part 630 and the refrigerant is also improved. The reinforcing part 650 has a rigidity that is higher than that of the main part 630 because its length in the Z direction gradually increases from the main part 630 towards the assembly part 640, and the formation of heat dissipation pins 690 makes it easier to exchange heat with the refrigerant.

[0107] The intersection point II of the virtual straight line VL connecting the boundary between the reinforcing portion 650 and the main portion 630 on the first inner surface 610b and the boundary between the reinforcing portion 650 and the assembly portion 640 with the first outer surface 610a is located on the assembly portion 640 side of the switch case 550 in the planar direction. The placement location (mounting area) of the switch case 550 on the first outer surface 610a is further away from the reinforcing portion 650 than the intersection point II in the planar direction.

[0108] According to this, the thermal resistance between the switch case 550 and the reinforcing part 650 increases. As a result, heat conduction between the switch case 550 and the main part 630 becomes easier. Consequently, stagnation of heat dissipation from the switch case 550 is suppressed. Furthermore, as described above, in this embodiment, heat dissipation pins 690 are formed on the reinforcing part 650. Therefore, even if heat is transferred from the switch case 550 to the reinforcing part 650, that heat can be actively dissipated by the heat dissipation pins 690 formed on the reinforcing part 650.

[0109] The first length L1 in the Z direction of the location where the heat dissipation pin 690 is formed in the reinforcing portion 650 is longer than the second length L2 in the Z direction of the heat dissipation pin 690 formed on the first inner surface 610b of the reinforcing portion 650.

[0110] According to this, distortion in the first case 610 is suppressed.

[0111] <Second Embodiment> This embodiment will be described primarily in terms of its differences from the first embodiment. In subsequent embodiments, the differences from the previously described embodiment will also be described primarily in terms of their differences. Configurations, operations, and effects not specifically described in other embodiments are the same as those described in the previously described embodiment.

[0112] In the first embodiment, as shown in Figure 14, an example was shown in which the position in the Z direction of the first bottom surface 621 where the inlet hole 670 opens is constant. In contrast, in this embodiment, as shown in Figure 15, a part of the alignment region 621a on the first bottom surface 621 that is aligned with the reinforcing portion 650 in the Z direction is inclined with respect to the Z direction. A part of the alignment region 621a is located on the second outer surface 620a side in the Z direction than the main region 621b on the first bottom surface 621 that is aligned with the main portion 630 in the Z direction.

[0113] The reinforcing portion 650 forms an annular shape in the circumferential direction. Therefore, the aligned region 621a, which is aligned with it in the Z direction, also forms an annular shape in the circumferential direction. This annular aligned region 621a is connected to the first annular surface 622. As described above, the first annular surface 622 has a first section screen 622a and a second section screen 622b aligned in the X direction, and a third section screen 622c and a fourth section screen 622d aligned in the Y direction. The region in the aligned region 621a that is connected to the first section screen 622a and extends in the Y direction is inclined with respect to the Z direction, as shown in Figure 15. The other three regions are not inclined with respect to the Z direction.

[0114] Furthermore, the three regions described above may be inclined with respect to the Z direction. That is, the region in the arrangement region 621a that is connected to the second section screen 622b and extends in the Y direction may be inclined with respect to the Z direction. The region in the arrangement region 621a that is connected to the third section screen 622c and extends in the X direction may be inclined with respect to the Z direction. The region in the arrangement region 621a that is connected to the fourth section screen 622d and extends in the X direction may be inclined with respect to the Z direction.

[0115] In the following, to avoid cumbersome notation, the region connected to the first section screen 622a in the arrangement region 621a and extending in the Y direction will simply be referred to as the arrangement region 621a. As shown in Figure 15, an inlet hole 670 is opened in this arrangement region 621a.

[0116] The arrangement region 621a has a first arrangement region 621c and a second arrangement region 621d. The first arrangement region 621c is located on the first section screen 622a side in the planar direction compared to the second arrangement region 621d. The first arrangement region 621c is located on the second outer surface 620a side in the Z direction compared to the second arrangement region 621d. The first arrangement region 621c is connected to the main region 621b via the second arrangement region 621d.

[0117] The second alignment region 621d is inclined with respect to the Z direction. In contrast, the second outer surface 620a is perpendicular to the Z direction. The separation distance (thickness) between the second alignment region 621d and the second outer surface 620a gradually increases in the X direction from the first alignment region 621c towards the main region 621b.

[0118] As described in the first embodiment, the position of the first outer surface 610a of the reinforcing portion 650 is constant in the Z direction, but the position of the first inner surface 610b of the reinforcing portion 650 changes in the Z direction. The first inner surface 610b of the reinforcing portion 650 is inclined with respect to the Z direction. In this embodiment, the thickness of the reinforcing portion 650 in the Z direction gradually increases in the surface direction from the main portion 630 toward the assembly portion 640.

[0119] As shown above, the second alignment region 621d and the first inner surface 610b of the reinforcing portion 650 are inclined with respect to the Z direction. The separation distance between these two surfaces in the direction perpendicular to them is constant in the X direction from the first alignment region 621c toward the main region 621b.

[0120] With the configuration described above, the difference between the flow path cross-sectional area between the parallel region 621a and the first inner surface 610b of the reinforcing portion 650 and the flow path cross-sectional area between the main region 621b and the first inner surface 610b of the main portion 630 is suppressed. In addition, the flow direction of the refrigerant flowing from the inlet hole 670 into the refrigerant passage 600a is more likely to be directed from the inlet hole 670 towards the discharge hole 680.

[0121] <Third Embodiment> In the first embodiment, as shown in Figure 14, the inlet hole 670 extends in the Z direction, and an example is shown where the opening position of the second outer surface 620a and the opening position of the second inner surface 620b are equal in the surface direction. In contrast, in the present embodiment, as shown in Figure 16, the inlet hole 670 extends in a direction inclined with respect to the Z direction, and the opening position of the second outer surface 620a and the opening position of the second inner surface 620b are different in the surface direction.

[0122] The opening on the second outer surface 620a of the inlet hole 670 is aligned with the first connecting surface 623a of the second bottom surface 623 in the Z direction. The opening on the second inner surface 620b of the inlet hole 670 is aligned with the reinforcing portion 650 in the Z direction. Also, the opening on the second inner surface 620b of the inlet hole 670 is aligned with the main portion 630 in the Z direction.

[0123] Due to this configuration, the opening of the second outer surface 620a of the inlet hole 670 is further from the main part 630 in the X direction than the opening of the second inner surface 620b. The opening of the second outer surface 620a is further from the discharge hole 680 in the X direction than the opening of the second inner surface 620b. The inlet wall surface 670a constituting the inlet hole 670 connects the opening of the second outer surface 620a and the opening of the second inner surface 620b in a straight line along the shortest path. The inlet wall surface 670a on the second inner surface 620b side of the inlet hole 670 is aligned with the reinforcing part 650 and the main part 630 in the Z direction.

[0124] In this embodiment, similar to the second embodiment, the first inner surface 610b of the reinforcing portion 650 is inclined in the Z direction such that the thickness of the reinforcing portion 650 in the Z direction gradually increases in the surface direction from the main portion 630 toward the assembly portion 640.

[0125] The inlet wall surface 670a and the first inner surface 610b of the reinforcing section 650 are inclined with respect to the Z direction. The distance between the region of the inlet wall surface 670a aligned with the reinforcing section 650 and the main section 630 in the Z direction and the first inner surface 610b of the reinforcing section 650 is the fourth length L4. In contrast, the opening diameter of the inlet hole 670 in a plane perpendicular to the Y direction is the third length L3. The fourth length L4 is longer than the third length L3.

[0126] According to this, the difference between the flow path cross-sectional area between the first inner surface 610b of the reinforcing portion 650 and the inflow wall surface 670a, and the flow path cross-sectional area between the first inner surface 610b of the main portion 630 and the second inner surface 620b of the second case is suppressed.

[0127] As shown in Figure 17, the discharge hole 680 also extends in a direction inclined with respect to the Z direction. The opening position of the second outer surface 620a and the opening position of the second inner surface 620b are different in the planar direction of the discharge hole 680.

[0128] The opening on the second outer surface 620a of the discharge hole 680 is aligned with the second connecting surface 623b of the second bottom surface 623 in the Z direction. The opening on the second inner surface 620b of the discharge hole 680 is aligned with the reinforcing portion 650 and the main portion 630 in the Z direction.

[0129] The opening of the second outer surface 620a of the discharge hole 680 is further from the main part 630 in the X direction than the opening of the second inner surface 620b. The opening of the second outer surface 620a is further from the inlet hole 670 in the X direction than the opening of the second inner surface 620b. The discharge wall surface 680a constituting the discharge hole 680 connects the opening of the second outer surface 620a and the opening of the second inner surface 620b in a straight line along the shortest path. The distance between the region of the discharge wall surface 680a that is aligned with the reinforcing part 650 and the main part 630 in the Z direction and the first inner surface 610b of the reinforcing part 650 is the fourth length L4.

[0130] This prevents the difference between the flow path cross-sectional area between the first inner surface 610b of the reinforcing portion 650 and the discharge wall surface 680a and the flow path cross-sectional area between the first inner surface 610b of the main portion 630 and the second inner surface 620b of the second case from becoming too large.

[0131] <Fourth Embodiment> In the first embodiment, as shown in Figure 14, an example was shown in which the thickness of the reinforcing portion 650 in the Z direction gradually increases from the main portion 630 toward the assembly portion 640. In contrast, in the present embodiment, as shown in Figure 18, the thickness of the reinforcing portion 650 in the Z direction gradually increases from the main portion 630 toward the assembly portion 640, and then becomes constant.

[0132] <Fifth Embodiment> In the first embodiment, as shown in Figures 11 and 12, an example was shown in which the formation density of the multiple heat dissipation pins 690 was constant regardless of location. In contrast, in the present embodiment, as shown in Figure 19, the formation density of the multiple heat dissipation pins 690 differs depending on the location.

[0133] To explain the formation density of the heat dissipation pins 690, as shown in Figure 19, the region between the first case 610 and the second case 620, including the refrigerant passage 600a, is divided into multiple regions aligned in the Y direction. The region on the reinforcing portion 650 side is referred to as region A, the central region of the main portion 630 in the Y direction is referred to as region C, and the region between region A and region C is referred to as region B. Regions A, B, C, B, and A are arranged in order in the Y direction.

[0134] The lengths in the Z direction of regions A, B, and C are the separation distance between the first inner surface 610b of the main portion 630 and the first bottom surface 621. These three regions include the first inner surface 610b and the heat dissipation pins 690 formed on the first inner surface 610b.

[0135] In the following, the region included in region A of the first inner surface 610b will be referred to as the first region 610d. The region included in region B of the first inner surface 610b will be referred to as the second region 610e. The region included in region C of the first inner surface 610b will be referred to as the third region 610f. As shown in Figure 19, the first region 610d, the second region 610e, the third region 610f, the second region 610e, and the first region 610d are arranged in order in the Y direction. At least a portion of the formation density of the heat dissipation pins 690 formed in these three types of regions is different.

[0136] As described above, the switch case 550 contains two heat-generating elements: a high-side switch 541 and a low-side switch 542. These two heat-generating elements are spaced apart in the Y direction. The two B regions are aligned with these two heat-generating elements in the Z direction. The second region 610e corresponds to the opposing region. The third region 610f corresponds to the central region.

[0137] Due to this configuration, the heat dissipation pin 690 that actively exchanges heat between the heat-generating element and the refrigerant is the heat dissipation pin 690 included in region B. A fast flow rate of the refrigerant that exchanges heat with this heat dissipation pin 690 is preferable from the viewpoint of heat dissipation of the heat-generating element. Therefore, a fast flow rate of the refrigerant in region B is preferable. The flow rate of the refrigerant in region B is preferably faster than the flow rates of the refrigerants in regions C and A.

[0138] To meet this requirement, the formation density of heat dissipation pins 690 in region B is lower than that of heat dissipation pins 690 in region C.

[0139] Due to the distribution of the heat dissipation pins 690 shown above, the flow rate of the refrigerant flowing through region B is increased. Heat exchange between the heat dissipation pins 690 and the refrigerant in region B is facilitated. The switches, which act as heat-generating elements aligned with region B in the Z direction, also exchange heat with the refrigerant more easily.

[0140] As shown in Figure 19, region A includes not only the first region 610d and the heat dissipation pins 690, but also a part of the reinforcing portion 650 and the first annular surface 622. Due to this configuration, the difficulty of refrigerant flow in region A depends not only on the heat dissipation pins 690, but also on the reinforcing portion 650 and the first annular surface 622. Therefore, even if the formation density of the heat dissipation pins 690 is the same in regions A, B, and C, refrigerant flow is more difficult in region A than in regions B and C.

[0141] For these reasons, the formation density of the heat dissipation pins 690 in region A and the formation density of the heat dissipation pins 690 in region B may be the same. Furthermore, if the flow rate of the refrigerant in region B is faster than the flow rate of the refrigerant in regions C and A, the formation density of the heat dissipation pins 690 in region A may be lower than the formation density of the heat dissipation pins 690 in region B.

[0142] <Sixth Embodiment> In the first embodiment, as shown in Figure 14, an example was shown in which the switch case 550 is provided on the first outer surface 610a of the main part 630. In contrast, in this embodiment, as shown in Figure 20, the switch case 550 is provided not only on the first outer surface 610a of the main part 630 but also on the first outer surface 610a of the reinforcing part 650. The mounting area for the switch case 550 in the first case 610 is the first outer surface 610a of both the main part 630 and the reinforcing part 650.

[0143] According to this, compared to a configuration in which the reinforcing part 650 and the switch case 550 are separated in the planar direction, the increase in the size of the case 600 in the planar direction is suppressed.

[0144] <Other variations> The disclosure in this specification is not limited to the exemplary embodiments. The disclosure encompasses the exemplary embodiments and variations thereof by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and elements shown in the embodiments, but can be implemented in various variations. The disclosure can be implemented in a variety of combinations. The disclosure may have additional parts that can be added to the embodiments. The disclosure encompasses embodiments in which parts and elements have been omitted. The disclosure encompasses substitutions or combinations of parts and elements between one embodiment and another. The scope of the disclosed technical field is not limited to the descriptions of the embodiments. The scope of the disclosed technical field is indicated by the claims and should be understood to include all modifications within the meaning and scope equivalent to the claims.

[0145] In this embodiment, an example is shown in which the power converter 300 is used in the in-vehicle system 100 of an electric vehicle. However, the use of the power converter 300 is not limited to the above example. The power converter 300 can be appropriately used in hybrid vehicles, trucks, drones, robots, and home appliances, etc.

[0146] In this embodiment, an example is shown in which the switch case 550 is pressed and fixed to the case 600 by the pressing member 700. However, for example, the capacitor case 521 may be pressed and fixed to the case 600 by the pressing member 700. The switch case 550 and the capacitor case 521 correspond to electrical components.

[0147] <Disclosure of Technical Ideas> This specification discloses several technical concepts, as listed in the following paragraphs. Some paragraphs are written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs are written in a multiple dependent form, referring to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical concepts. <Technical philosophy 1> A cooler (600) in which electrical components (521, 550) included in a power conversion circuit (500) are pressed in a first direction by a pressing member (700), A first case (610) comprising a first outer surface (610a) and a first inner surface (610b) aligned in the first direction, the first outer surface against which the electrical components are pressed, The present invention comprises a second case (620) having a second outer surface (620a) and a second inner surface (620b) aligned in the first direction, wherein the second inner surface is located closer to the first inner surface in the first direction than the second outer surface, and the second inner surface faces the first inner surface at a distance in the first direction, thereby forming a refrigerant passage (600a) through which the refrigerant flows together with the first case, The first case mentioned above is, The main part (630) against which the electrical component is pressed by the pressing member, An assembly portion (640) that forms an annular shape in the circumferential direction around the first direction and is assembled to the second case, It has a reinforcing portion (650) that forms an annular shape in the circumferential direction and is located between the main portion and the assembly portion in a planar direction perpendicular to the first direction, connecting the main portion and the assembly portion. The reinforcing portion of the cooler is longer in the first direction than the main portion and shorter in the first direction than the assembly portion. <Technical philosophy 2> The cooler according to technical concept 1, wherein a plurality of heat dissipation pins (690) extending from the first inner surface toward the second inner surface are formed on the first inner surface side of the main part and on the first inner surface side of the reinforcing part. <Technical philosophy 3> The first inner surface of the reinforcing portion is inclined with respect to the first direction such that the length of the reinforcing portion in the first direction increases in the surface direction from the main portion toward the assembly portion, The cooler according to technical concept 2, wherein the region (621a) on the second inner surface of the second case that is aligned with the reinforcing portion in the first direction is inclined with respect to the first direction such that the separation distance between the reinforcing portion and the first inner surface is constant. <Technical philosophy 4> The cooler according to technical concept 2, wherein the second case has through holes (670, 680) that penetrate the second inner surface and the second outer surface and communicate with the refrigerant passage. <Technical philosophy 5> The first inner surface of the reinforcing portion is inclined with respect to the first direction such that the length of the reinforcing portion in the first direction increases in the surface direction from the main portion toward the assembly portion, The opening on the second outer surface of the through hole is spaced further away from the main part in the surface direction than the opening on the second inner surface. The through hole extends in a direction in which the opening on the second outer surface and the opening on the second inner surface are aligned. The cooling device according to technical concept 4, wherein the opening on the second inner surface side of the through hole is aligned with the reinforcing portion in the first direction. <Technical philosophy 6> The aforementioned plane direction includes a second and a third direction which are mutually orthogonal to each other. The through-hole includes an inlet (670) through which the refrigerant flows in and an outlet (680) through which the refrigerant is discharged. The inlet hole and the outlet hole are separated in the second direction. The electrical component includes two heating elements (541, 542) that are spaced apart in the third direction, The cooler according to Technical Idea 4 or Technical Idea 5, wherein the formation density of the heat dissipation pins in two opposing regions (610e) on the first inner surface of the main part, aligned with the heating element in the first direction, is lower than the formation density of the heat dissipation pins in the central region (610f) between the two opposing regions on the first inner surface of the main part. <Technical philosophy 7> The cooler according to any one of technical ideas 2 to 6, wherein the length in the first direction of the location where the heat dissipation pin is formed in the reinforcing portion is longer than the length in the first direction from the first inner surface of the reinforcing portion to the tip of the heat dissipation pin formed in the reinforcing portion. <Technical philosophy 8> The cooling device according to any one of technical concepts 2 to 7, wherein the mounting area for the electrical components in the first case is the first outer surface of the main part and the reinforcing part. <Technical philosophy 9> A cooler according to any one of technical concepts 2 to 7, wherein the mounting area for the electrical components on the first outer surface is further away from the reinforcing portion in the surface direction than the intersection point (II) of the imaginary straight line (VL) connecting the boundary between the assembly portion and the reinforcing portion on the first inner surface and the boundary between the reinforcing portion and the main portion on the first inner surface with the first outer surface. <Technical Thought 10> The electrical components (521, 550) included in the power conversion circuit (500), A cooler (600) on which the aforementioned electrical components are provided, A power conversion device having a pressing member (700) for pressing and fixing the electrical components to the cooler in a first direction, The aforementioned cooler is, A first case (610) comprising a first outer surface (610a) and a first inner surface (610b) aligned in the first direction, the first outer surface against which the electrical components are pressed, The present invention comprises a second case (620) having a second outer surface (620a) and a second inner surface (620b) aligned in the first direction, wherein the second inner surface is located closer to the first inner surface in the first direction than the second outer surface, and the second inner surface faces the first inner surface at a distance in the first direction, thereby forming a refrigerant passage (600a) through which the refrigerant flows together with the first case, The first case mentioned above is, The main part (630) against which the electrical component is pressed by the pressing member, An assembly portion (640) that forms an annular shape in the circumferential direction around the first direction and is assembled to the second case, It has a reinforcing portion (650) that forms an annular shape in the circumferential direction and is located between the main portion and the assembly portion in a planar direction perpendicular to the first direction, connecting the main portion and the assembly portion. The reinforcing portion is longer in the first direction than the main portion and shorter in the first direction than the assembly portion of the power conversion device. [Explanation of symbols]

[0148] 100...In-vehicle system, 200...Battery, 300...Power converter, 400...Motor, 500...Power conversion circuit, 520...Smoothing capacitor, 521...Capacitor case, 541...High-side switch, 542...Low-side switch, 550...Switch case, 600...Case, 600a...Refrigerant passage, 610...First case, 610a...First outer surface, 610b...First inner surface, 610c... Side view, 610d...First region, 610e...Second region, 610f...Third region, 620...Second case, 620a...Second outer surface, 620b...Second inner surface, 621a...Alignment region, 630...Main part, 640...Assembly part, 650...Reinforcement part, 670...Inlet hole, 670a...Inlet wall surface, 680...Discharge hole, 680a...Discharge wall surface, 690...Heat dissipation pin, 700...Pressing member, II...Intersection position, VL...Virtual straight line

Claims

1. A cooler (600) in which electrical components (521, 550) included in a power conversion circuit (500) are pressed in a first direction by a pressing member (700), A first case (610) comprising a first outer surface (610a) and a first inner surface (610b) aligned in the first direction, the first outer surface against which the electrical components are pressed, The second case (620) comprises a second outer surface (620a) and a second inner surface (620b) aligned in the first direction, wherein the second inner surface is located closer to the first inner surface in the first direction than the second outer surface, and the second inner surface faces the first inner surface at a distance in the first direction, thereby forming a refrigerant passage (600a) through which the refrigerant flows together with the first case. The first case mentioned above is, The main part (630) against which the electrical component is pressed by the pressing member, An assembly portion (640) that forms an annular shape in the circumferential direction around the first direction and is assembled to the second case, It has a reinforcing portion (650) that forms an annular shape in the circumferential direction and is located between the main portion and the assembly portion in a planar direction perpendicular to the first direction, connecting the main portion and the assembly portion. The reinforcing portion of the cooler has a longer length in the first direction than the main portion and a shorter length in the first direction than the assembly portion.

2. The cooler according to claim 1, wherein a plurality of heat dissipation pins (690) extending from the first inner surface toward the second inner surface are formed on the first inner surface side of the main part and on the first inner surface side of the reinforcing part.

3. The first inner surface of the reinforcing portion is inclined with respect to the first direction such that the length of the reinforcing portion in the first direction increases in the surface direction from the main portion toward the assembly portion, The cooler according to claim 2, wherein the region (621a) on the second inner surface of the second case that is aligned with the reinforcing portion in the first direction is inclined with respect to the first direction such that the separation distance from the first inner surface of the reinforcing portion is constant.

4. The cooler according to claim 2, wherein the second case has through holes (670, 680) that penetrate the second inner surface and the second outer surface and communicate with the refrigerant passage.

5. The first inner surface of the reinforcing portion is inclined with respect to the first direction such that the length of the reinforcing portion in the first direction increases in the surface direction from the main portion toward the assembly portion, The opening on the second outer surface of the through hole is spaced further away from the main part in the surface direction than the opening on the second inner surface. The through hole extends in a direction in which the opening on the second outer surface and the opening on the second inner surface are aligned. The cooler according to claim 4, wherein the opening on the second inner surface side of the through hole is aligned with the reinforcing portion in the first direction.

6. The aforementioned plane direction includes a second and a third direction which are mutually orthogonal to each other. The through-hole includes an inlet (670) through which the refrigerant flows in and an outlet (680) through which the refrigerant is discharged. The inlet hole and the outlet hole are separated in the second direction. The electrical component includes two heating elements (541, 542) that are spaced apart in the third direction, The cooler according to claim 4, wherein the formation density of the heat dissipation pins in two opposing regions (610e) on the first inner surface of the main part, which are aligned with the heating element in the first direction, is lower than the formation density of the heat dissipation pins in the central region (610f) between the two opposing regions on the first inner surface of the main part.

7. The cooler according to claim 2, wherein the length in the first direction of the location where the heat dissipation pin is formed in the reinforcing portion is longer than the length in the first direction from the first inner surface of the reinforcing portion to the tip of the heat dissipation pin formed in the reinforcing portion.

8. The cooler according to claim 2, wherein the mounting area for the electrical components in the first case is the first outer surface of the main part and the reinforcing part.

9. The cooler according to claim 2, wherein the mounting area for the electrical components on the first outer surface is spaced further away from the reinforcing portion in the surface direction than the intersection point (II) of the imaginary straight line (VL) connecting the boundary between the assembly portion and the reinforcing portion on the first inner surface and the boundary between the reinforcing portion and the main portion on the first inner surface with the first outer surface.

10. Electrical components (521, 550) included in the power conversion circuit (500), A cooler (600) on which the aforementioned electrical components are provided, A power conversion device having a pressing member (700) for pressing and fixing the electrical components to the cooler in a first direction, The aforementioned cooler is, A first case (610) comprising a first outer surface (610a) and a first inner surface (610b) aligned in the first direction, the first outer surface against which the electrical components are pressed, The second case (620) comprises a second outer surface (620a) and a second inner surface (620b) aligned in the first direction, wherein the second inner surface is located closer to the first inner surface in the first direction than the second outer surface, and the second inner surface faces the first inner surface at a distance in the first direction, thereby forming a refrigerant passage (600a) through which the refrigerant flows together with the first case. The first case mentioned above is, The main part (630) against which the electrical component is pressed by the pressing member, An assembly portion (640) that forms an annular shape in the circumferential direction around the first direction and is assembled to the second case, It has a reinforcing portion (650) that forms an annular shape in the circumferential direction and is located between the main portion and the assembly portion in a planar direction perpendicular to the first direction, connecting the main portion and the assembly portion. The reinforcing portion is longer in the first direction than the main portion and shorter in the first direction than the assembly portion of the power conversion device.

Images