Electronic control module

Abstract

An electronic control module 1 comprises: a plate-shaped first circuit board 20 and a plate-shaped second circuit board 30 respectively having a plurality of electronic components 21, 31 mounted on surfaces thereof; and a bracket 40 that has a frame shape along the outer periphery of the first circuit board 20 and the second circuit board 30, and is provided between the first circuit board 20 and the second circuit board 30 to support the same in the vertical direction. The bracket 40 has a first opening 41 and a second opening 42 that connect the inside and outside of a space surrounded by the first circuit board 20, the second circuit board 30, and the bracket 40. The second opening 42 is formed in the upper portion of the bracket 40.

Description

Electronic Control Module

[0001] The present invention relates to electronic control modules.

[0002] WO2013 / 088642A1 discloses a power converter in which a circuit board on which various components such as switching elements are mounted is arranged at an angle above a power module. In this power converter, heat emitted from heat-generating components rises along the inclined surface of the circuit board, thereby suppressing heat retention in the circuit board.

[0003] The power conversion device described in the above document has the problem that the circuit board needs to be arranged at an angle, which places restrictions on the mounting of components, and also requires special processing of the components to arrange the circuit board at an angle, which increases the cost of the components and the number of work steps.

[0004] The present invention has been made in consideration of these technical challenges, and aims to provide an electronic control module that can be easily cooled while preventing the device from becoming larger, even when heat-generating components are installed on a circuit board.

[0005] According to one aspect of the present invention, an electronic control module includes a plate-shaped first circuit board having heat-generating components mounted on its surface, a second circuit board having electrical components mounted on its surface, and a bracket having a frame shape that follows the outer peripheries of the first and second circuit boards and supports them from above and below. The bracket has a first opening and a second opening that communicate between the inside and outside of a space enclosed by the first circuit board, the second circuit board, and the bracket. The second opening is formed in an upper part of the bracket.

[0006] Fig. 1 is a perspective view of the appearance of an electronic control module of this embodiment. Fig. 2 is a cross-sectional view of the electronic control module. Fig. 3 is a cross-sectional view of an electronic control module of a modified example. Fig. 4 is a cross-sectional view of an electronic control module of another modified example.

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0008] FIG. 1 is an external perspective view of an electronic control module 1 of this embodiment, and FIG. 2 is a cross-sectional view of the electronic control module 1 of this embodiment taken along line II-II in FIG.

[0009] The electronic control module 1 of this embodiment is used, for example, in a power control unit that controls a motor generator mounted on a hybrid vehicle.

[0010] As shown in Figures 1 and 2, the electronic control module 1 comprises a power module 10 as a base, a driver board 20 as a first circuit board arranged on the power module 10, a motor control board 30 as a second circuit board arranged on the upper surface side of the driver board 20 at a distance, and a frame-shaped bracket 40 provided between the driver board 20 and the motor control board 30.

[0011] The power module 10 includes a plurality of power elements that convert DC power supplied from a battery mounted on the vehicle into AC power through switching control. The power module 10 supplies the AC power converted by the power elements to a motor generator. The power module 10 includes power supply terminals 12 (12A, 12B, 12C, 12D, 12E) for inputting and outputting power.

[0012] 2, a cooling device 11 is provided below the power module 10. The cooling device 11 includes a refrigerant flow path 11A through which a refrigerant flows, and a plurality of metal fins 11B protruding into the refrigerant flow path 11A. Heat is exchanged between the refrigerant flowing through the cooling device 11 and the power elements via the fins 11B, thereby cooling the power elements.

[0013] The driver board 20 controls the switching operation of the power module 10. The driver board 20 is formed of a multilayer printed circuit board. As shown in Figure 2, a plurality of electronic components 21 (such as a controller, a transformer, a diode, a capacitor, and a chip resistor) are mounted on an upper surface 20a of the driver board 20. These electronic components 21 form a switching circuit.

[0014] The driver board 20 is fixed onto the power module 10 together with the bracket 40 by fastening a flange portion 43 formed on the bracket 40 and the power module 10 together with screws 3 .

[0015] The motor control board 30 controls the operation of the switching circuit of the driver board 20 in accordance with the vehicle driving state. The motor control board 30 is formed of a multilayer printed circuit board. A plurality of electronic components 31 (such as a controller, a power supply IC, coils, capacitors, connectors, and chip resistors) are mounted on the top surface 30a of the motor control board 30. These electronic components 31 constitute a motor control circuit. The motor control circuit controls the voltage, current, and frequency of the switching operation in the switching circuit of the driver board 20. The motor control board 30 is fixed to the top surface of the bracket 40 with screws 2.

[0016] The bracket 40 is formed as a generally rectangular cylindrical frame that conforms to the shapes of the outer edges of the driver board 20 and the motor control board 30. The bracket 40 is fixed to the upper surface 20a of the driver board 20 and supports the motor control board 30 from its lower surface 30b, thereby supporting the driver board 20 and the motor control board 30 at a distance from each other. The bracket 40 is made of a resin material (e.g., polyphenylene sulfide resin).

[0017] The bracket 40 defines an internal space F surrounded by the driver board 20, the motor control board 30, and the frame of the bracket 40. The electronic components 21 mounted on the driver board 20 are disposed within this internal space F.

[0018] When the power module 10 is operated, a switching circuit of the driver board 20 operates to control the operation of the power module 10. As shown in Fig. 2, the electronic components 21 arranged on the upper surface 20a of the driver board 20 include electronic components that generate particularly large amounts of heat (hereinafter referred to as "heat-generating components 21a"), and their temperatures rise during operation. The heat-generating components 21a are, for example, controllers or chip resistors.

[0019] Here, since the heat-generating component 21a is disposed within the internal space F of the bracket 40, if air stagnates within the internal space F, the ambient temperature within the internal space F will rise, which may further increase the temperature of the heat-generating component 21a. For this reason, some means of releasing the heat within the internal space F is required.

[0020] Therefore, in this embodiment, in order to prevent heat from accumulating in the internal space F, the following configuration is provided.

[0021] As shown in the cross-sectional view of Fig. 2, bracket 40 has a first opening 41 on one side (left side in Fig. 2) that opens to allow communication between the inside and outside of bracket 40. The other side (right side in Fig. 2) of bracket 40 has a second opening 42 that opens to allow communication between the inside and outside of bracket 40. The first opening 41 opens at the location where bracket 40 and driver board 20 contact, i.e., at the bottom of bracket 40. The second opening 42 opens at the location where bracket 40 and motor control board 30 contact, i.e., at the top of bracket 40.

[0022] More specifically, a first opening 41 having a rectangular shape in a side view (arrow A in FIG. 1 ) opens in a wall portion 44 on one side of the bracket 40. Similarly, a second opening 42 having a rectangular shape in a side view opens in a wall portion 45 on the other side of the bracket 40.

[0023] 2 , the first opening 41 and the second opening 42 are provided in wall portions 44 and 45, respectively, which are arranged spaced apart from each other in the lateral direction (width direction) of the bracket 40. With this configuration, the first opening 41 and the second opening 42 are arranged spaced apart from each other in the width direction of the bracket 40. The second opening 42 is arranged at a position higher in the up-down direction than the first opening 41, and the first opening 41 and the second opening 42 are arranged spaced apart from each other in the up-down direction of the bracket 40.

[0024] In the electronic control module 1 configured in this manner, when the temperature of the heat-generating component 21 a rises, the air near the heat-generating component 21 a is heated and rises. When the rising air reaches the motor control board 30, it flows in a direction along the underside 30 b of the motor control board 30 and then flows out of the bracket 40 through the second opening 42.

[0025] In this way, the air heated inside the bracket 40 flows out through the second opening 42, which reduces the air pressure in the internal space F of the bracket 40. This creates a draft effect, causing air outside the bracket 40 to flow in through the first opening 41.

[0026] As a result, air outside the electronic control module 1 is constantly circulating in the internal space F of the bracket 40. By constantly circulating air from the outside to the heat-generating component 21a, the temperature in the internal space F is suppressed from rising, and the temperature of the heat-generating component 21a is prevented from rising more than necessary.

[0027] In particular, in the internal space F of the bracket 40, the air flowing in from the first opening 41 formed at the bottom of the bracket 40 flows toward the second opening 42, along the surface of the heat-generating component 21a of the driver board 20, thereby efficiently lowering the temperature of the heat-generating component 21a.

[0028] As described above, the electronic control module 1 of this embodiment includes the driver board 20 as a plate-like first circuit board and the motor control board 30 as a plate-like second circuit board, each having a plurality of electronic components 21, 31 mounted on its surface, and the bracket 40, which has a frame shape that follows the outer peripheries of the driver board 20 and the motor control board 30 and supports them in the vertical direction between the driver board 20 and the motor control board 30. The bracket 40 has a first opening 41 and a second opening 42 that communicate between the inside and the outside of the space surrounded by the driver board 20, the motor control board 30, and the bracket 40. The second opening 42 is formed in the upper part of the bracket 40.

[0029] In this configuration, when the air in the internal space F of the bracket 40 is heated due to a rise in temperature of the electronic components (heat-generating components 21 a arranged on the driver board 20), the air rises and is discharged through the second opening 42 arranged on the upper side of the bracket 40. This reduces the air pressure in the internal space F and allows external air to flow in through the first opening 41, ensuring that external air constantly flows through the heat-generating components 21 a, preventing the temperature of the heat-generating components 21 a from rising more than necessary. This eliminates the need to add a new cooling configuration to the electronic control module 1, making it possible to more easily cool the heat-generating components 21 a while preventing the electronic control module 1 from becoming larger.

[0030] In this embodiment, the first opening 41 and the second opening 42 are arranged spaced apart from each other in the width direction of the bracket 40, with the first opening 41 being located at the bottom of the bracket 40 and the second opening 42 being located at the top of the bracket 40.

[0031] In this configuration, the air flowing in from the first opening 41 flows laterally along the surface of the heat-generating component 21a on the driver board 20, thereby efficiently cooling the heat-generating component 21a.

[0032] Next, a modification of this embodiment will be described with reference to FIG.

[0033] FIG. 3 is a cross-sectional view of the electronic control module 1 according to a modified example of this embodiment, taken along line II-II.

[0034] The configuration shown in Figure 3 differs from the configuration in Figure 2 in that multiple electronic components 31 arranged on the motor control board 30 are mounted so as to protrude downward from the lower surface 30b of the motor control board 30.

[0035] The electronic control module 1 of the modified example shown in FIG. 3 is configured so that its vertical height H2 is approximately the same as the vertical height H1 of the electronic control module 1 shown in FIG.

[0036] The electronic components 31 mounted on the lower surface 30b of the motor control board 30 include tall components 31b that are particularly large in height. The bracket 40 is configured to be tall enough so that the tall components 31b do not interfere with the driver board 20 in the internal space F. As a result, in the modified example shown in Fig. 3, the internal space F of the bracket 40 is configured to be larger in height than the configuration shown in Fig. 2.

[0037] Furthermore, the connector part 33 of the electronic component 31 to which the harness 32 from the outside is connected is disposed near the second opening 42 , and the harness 32 is connected via the second opening 42 .

[0038] By configuring it in this manner, even if electronic components 31 are placed on the underside 30b of the motor control board 30, it is possible to connect a harness 32 for communicating with the outside of the electronic control module 1 to the connector component 33.

[0039] In the modified example of this embodiment configured as shown in FIG. 3, the motor control board 30 has the electronic components 31 mounted upright toward the driver board 20 on the underside 30b on the side where the bracket 40 is disposed.

[0040] In this configuration, the height of the internal space F of the bracket 40 is configured to be higher compared to the configuration shown in Fig. 2. As a result, the air heated in the internal space F rises due to a rise in temperature of the heat-generating component 21a, reducing the density of the air near the bottom of the internal space F. This makes it easier for air to flow in through the first opening 41.

[0041] In the modified example shown in Fig. 3, the height of the internal space F is increased, so that the airflow along the surface of the heat-generating component 21a of the driver board 20 is larger than in the configuration shown in Fig. 2, and the temperature of the heat-generating component 21a can be more efficiently reduced. As a result, the size of the electronic control module 1 can be prevented from increasing, and the heat-generating component 21a can be cooled more efficiently.

[0042] 3, tall components 31b that are particularly tall may be mounted on the lower surface 30b of the motor control board 30, and low-profile components (e.g., surface-mounted chip resistors or controllers) that are short in height among the electronic components 31 may be mounted on the upper surface 30a of the motor control board 30. In this case, any components may be mounted on the upper surface 30a of the motor control board 30 as long as the height H2 of the electronic control module 1 including the low-profile components does not exceed the height H1 of the electronic control module 1 shown in FIG.

[0043] FIG. 4 is a cross-sectional view of an electronic control module 1 according to yet another modification of this embodiment, taken along line II-II.

[0044] The configuration shown in FIG. 4 differs from the configuration shown in FIG. 3 in that the heat generating component 21 a of the driver board 20 is disposed at a position adjacent to the wall portion 44 on the second opening 42 side of the bracket 40 .

[0045] More specifically, the driver board 20 has a heat-generating component 21a mounted on the upper surface 20a of the side fixed to the bracket 40, and is positioned adjacent to the wall portion 45 on the side having the second opening 42 of the bracket 40.

[0046] It is generally known that when gas flows along a wall, surrounding gas is drawn into the flow of gas (the Coanda effect). Due to this effect, when the heat-generating component 21a is positioned adjacent to the wall 45 of the bracket 40, the air heated by the heat-generating component 21a and rising along the wall 45 draws in surrounding air, and the amount of air flowing toward the second opening 42 increases compared to the configuration of Fig. 3 .

[0047] In this way, by arranging the heat-generating component 21a adjacent to the wall portion 45 of the bracket 40, more air can be allowed to flow out from the second opening 42, and a larger amount of air can flow in from the first opening 41, thereby increasing the amount of air flowing along the surface of the heat-generating component 21a of the driver board 20. As a result, the heat-generating component 21a can be efficiently cooled while preventing the electronic control module 1 from becoming larger.

[0048] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments.

[0049] In the above embodiment, the electronic control module 1 is described as being used in a power control unit of a hybrid vehicle, but the present invention is not limited to this and may be used in various industrial machines and the like.

[0050] Although the first opening 41 and the second opening 42 of the bracket 40 are described as being arranged in the opposing wall portions 44, 45, this is not limitative. The first opening 41 may be arranged in one of the orthogonally adjacent wall portions, and the second opening 42 may be arranged in the other wall portion.

[0051] Alternatively, the first opening 41 may not be provided, and the configuration may be such that air flows in through the gap between the driver board 20 and the bracket 40, and at least the second opening 42 may be located at the top of one of the side walls of the bracket 40.

Claims

1. An electronic control module comprising: a first circuit board having heat-generating components mounted on its surface; a second circuit board having electronic components mounted on its surface; and a bracket having a frame shape that follows the outer peripheries of the first circuit board and the second circuit board and supports the first circuit board and the second circuit board from above and below, wherein the bracket has a first opening and a second opening that communicate between the inside and outside of an internal space surrounded by the first circuit board, the second circuit board, and the bracket, and the second opening is formed in the upper part of the bracket.

2. An electronic control module according to claim 1, wherein the first opening and the second opening are spaced apart from each other in the width direction of the bracket, the first opening being located at the bottom of the bracket, and the second opening being located at the top of the bracket.

3. An electronic control module according to claim 1, wherein the electronic components are mounted on the underside of the second circuit board on the side where the bracket is located, in an upright position facing the second circuit board.

4. An electronic control module according to claim 3, wherein the electronic component includes a connector to which a harness is connected, and the harness is connected to the connector from outside the internal space via the second opening.

5. An electronic control module according to claim 1, wherein the heat-generating component is mounted on the upper surface of the second circuit board on the side fixed to the bracket, and the heat-generating component is disposed adjacent to the inner surface of the bracket on the side having the second opening.

6. An electronic control module according to any one of claims 1 to 5, comprising a power module that controls the operation of a motor, wherein the second circuit board is a driver board provided on the power module and on which a switching circuit that controls the switching operation of the power module is provided, and the first circuit board is a motor control board that controls the operation of the switching circuit provided on the second circuit board in accordance with the vehicle operating state, and is supported above the second circuit board via the bracket.

Images