Mounting structure of heat-generating components

Abstract

To provide an attaching structure for heat-generating components that can improve heat dissipation performance of the heat-generating components and EMC performance.SOLUTION: An attaching structure for a heat-generating component 17 includes a component attaching plate 16 to which the heat-generating component 17 is attached, and a case 14 that houses a connector 18 provided on a board 15, the component attaching plate 16, and the heat-generating component 17. The component attaching plate 16 includes a partition 19 that partitions the inside of the case 14 into a space A1 where the connector 18 is stored and a space A2 where components other than the connector are stored, and a connection portion 20 that connects the partition 19 and the case 14. The heat-generating component 17 is attached to the partition 19, and the partition 19, the connection portion 20, and part of the case 14 cover the connector 18. The heat-generating component 17 is attached to the partition 19 via a fastening member.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a mounting structure for a heat generating component that can be used, for example, in a mechatronic electric actuator or the like.

Background Art

[0002] A technique has been proposed for ensuring the heat dissipation performance and EMC (electromagnetic compatibility) performance of a controller by means of the arrangement of components and the shape of a case covering a printed circuit board (Patent Document 1). In Patent Document 1, as shown in FIG. 13, heat generating components 7 surface-mounted on a printed circuit board 5 are arranged in a row in the longitudinal direction of a connector 6 in the vicinity of the connector 6. Further, as shown in FIG. 14, a part 3b of a case 2 is formed in a concave shape that contacts the heat generating component 7 to ensure heat dissipation. Also, by covering the connector pins 6b with the case 2, the role of a shield plate as a noise countermeasure is fulfilled to ensure EMC performance.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The conventional technique is applicable only to surface-mounted components and has the problem shown in FIG. 15. Since a lead component 38 is soldered after inserting its leads into through holes of a substrate 32, it is necessary to fix it with a heat sink 39. By arranging the heat sink 39 in contact with the wall surface of a case 34, the heat dissipation performance of the lead component 38 is ensured.

[0005] However, the heat dissipation effect of the leaded component 38 cannot be obtained unless the heatsink 39 is positioned in contact with the wall of the case 34. If the leaded component 38 is positioned near the wall of the case 34, the distance between the leaded component 38 and the connector 36 will be increased, which may result in longer pattern wiring 35 and inefficient use of mounting area. To secure components during soldering and shorten pattern wiring, one method is to insert the component mounting plate 1 into the printed circuit board 12, as shown in Figure 16 (Patent Document 2), but this method does not provide heat dissipation.

[0006] The objective of the present invention is to provide a mounting structure for heat-generating components that can improve the heat dissipation of the heat-generating components and enhance EMC performance. [Means for solving the problem]

[0007] The heat-generating component mounting structure of the present invention comprises a component mounting plate on which the heat-generating component is attached, The circuit board comprises a connector, a component mounting plate, and a case for housing the heat-generating component. The component mounting plate includes a partition wall that separates the space in the case where the connector is housed from the space where other specified components are housed, and a connecting portion that connects the partition wall to the case. The heat-generating component is attached to the partition wall, and the connector is covered by the partition wall, the connecting portion, and a part of the case. The aforementioned specified parts are parts that are arbitrarily determined by the design, etc.

[0008] In this configuration, heat-generating components are mounted on the partition wall of the component mounting plate, and a connecting section is provided between the partition wall and the case. This allows heat from the heat-generating components to be dissipated to the case through the connecting section. The connector is covered by the partition wall and connecting section of the component mounting plate and a part of the case. In this way, the component mounting plate is used as a shielding material, and the component mounting plate, acting as a shielding material, and a part of the case work together to block noise and other signals radiated from the connector. Therefore, compared to conventional technology, the heat dissipation of heat-generating components can be improved, and EMC performance can be enhanced.

[0009] The heat-generating component may be attached to the partition wall via a fastening member. In this case, the mounting structure for the heat-generating component can be simplified, and manufacturing costs can be reduced.

[0010] The case and the connecting portion may be formed as a single unit. The phrase "integrally constructed" means that the case and the connecting part are not formed by combining multiple elements, but rather are formed from a single material, for example, by forging, machining, etc., as part of or as a whole of a single object. In this case, compared to a structure where the case and the connecting part are separate components, the number of parts and assembly time can be reduced. This, in turn, can reduce manufacturing costs.

[0011] The circuit board and the terminals of the electric actuator may be electrically connected by press-fit or connector. In this case, assembly can be simplified compared to a configuration where the circuit board and the terminals of the electric actuator are soldered together, for example. [Effects of the Invention]

[0012] In the heat-generating component mounting structure of the present invention, the heat-generating component is mounted on a partition wall of a component mounting plate, and a connecting portion is provided between the partition wall and the case, so that heat from the heat-generating component can be dissipated to the connecting portion and the case. Since the connector is covered by the partition wall and connecting portion of the component mounting plate and a part of the case, noise and other radiated from the connector can be blocked. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view showing a mounting structure for a heat-generating component according to the first embodiment of the present invention. [Figure 2] This is a vertical cross-sectional view of the main part of the case that houses the heat-generating components. [Figure 3] This is a perspective view of the component mounting plate to which the heat-generating component is attached. [Figure 4] This is a perspective view of the mounting plate for the same component, seen from a different direction. [Figure 5]It is a perspective view showing an attachment structure of a heat generating component according to a second embodiment of the present invention. [Figure 6] It is a perspective view of a case for housing the heat generating component and the like. [Figure 7] It is a longitudinal sectional view of a main part of the case. [Figure 8] It is a partially enlarged view showing a press fit connection type between a substrate provided in the case and a motor terminal. [Figure 9] It is a longitudinal sectional view of an example in which the press fit connection type is changed to a connector connection type. [Figure 10] It is a partially enlarged view of the connector connection type. [Figure 11] It is a longitudinal sectional view showing an attachment structure of a heat generating component according to a third embodiment of the present invention. [Figure 12] It is a longitudinal sectional view of an example in which the press fit connection type in FIG. 11 is changed to a connector connection type. [Figure 13] It is a perspective view showing an attachment example of a heat generating component of a conventional example. [Figure 14] It is a sectional view of a main part of the heat generating component and the like. [Figure 15] It is a perspective view showing an attachment example of a heat generating component of another conventional example. [Figure 16] It is a perspective view showing an attachment example of a heat generating component of still another conventional example.

Mode for Carrying Out the Invention

[0014] [First Embodiment] The attachment structure of the heat generating component according to the embodiment of the present invention will be described together with FIGS. 1 to 4. This attachment structure of the heat generating component is applied to, for example, an electromechanical integrated electric actuator. As shown in FIG. 1, the electromechanical integrated electric actuator 10 is a product in which a motor 11 and a control device 13 for controlling the motor 11 are made as one unit. The electric actuator 10 is mounted on a vehicle, for example, and is used as a drive source for driving in-vehicle devices and the like.

[0015] <000​ The motor 11 is, for example, a permanent magnet synchronous motor. Other types of motors 11, such as a switched reluctance motor or an induction motor, can also be used. The motor 11 comprises a mounting flange 11a for attaching it to the mounting object, and a motor body 11b fixed to the upper part of the mounting flange 11a. A control device 13 is fixed to a part of the motor body 11b (the upper part in this example).

[0016] <Control device> The control device 13 controls the motor 11 according to command values ​​from a higher-level control device. The higher-level control device may be, for example, a vehicle control ECU, which is an electrical control unit that controls the entire vehicle. The control device 13 may also output various information, such as detected values ​​and control values ​​related to the motor 11, to the higher-level control device.

[0017] The control device 13 comprises a case 14, a circuit board 15, a component mounting plate 16, a heat-generating component 17, a connector 18, and other components. The connector 18, component mounting plate 16, heat-generating component 17, and other components, which are provided on the circuit board 15, are housed in the case 14. The case 14 is, for example, a rectangular parallelepiped in appearance and is formed from a thin sheet of metal by machining or the like. The metal used can be, for example, aluminum or iron.

[0018] As shown in Figure 2, a rectangular plate-shaped substrate 15 is supported near the bottom of the case 14. The substrate 15 is a so-called printed circuit board, and the printed circuit board 15 is equipped with electrical circuits for driving the motor 11 (Figure 1). The heat-generating component 17 is attached to the component mounting plate 16, and the component mounting plate 16 is fixed to the printed circuit board 15. The heat-generating component 17 includes multiple leaded components, which are, for example, multiple switching elements that convert DC power from a battery (not shown) into AC power used to drive the motor 11 (Figure 11). As the switching elements, for example, semiconductor switching elements such as IGBTs or MOS-FETs are used.

[0019] The aforementioned higher-level control device is electrically connected to the heat-generating component 17 via the connector 18 and the electrical circuit. The heat-generating component 17 is electrically connected to the motor 11 and the battery shown in Figure 1 via the electrical circuit and the connector 18. By opening and closing a switching element according to a command value from the higher-level control device, the DC power is converted into AC power used to drive the motor 11. Heat is generated from the switching element when it is opened and closed. The connector 18 is supported on the substrate 15 along one side inside the case 14.

[0020] <Regarding mounting plates for parts, etc.> As shown in Figure 3, the component mounting plate 16 includes a partition wall 19 and a connecting portion 20. As shown in Figure 4, the partition wall 19 and the connecting portion 20 are integrally formed from a thin sheet of metal by machining or the like, and have a certain thickness. For example, aluminum or iron can be used as the metal. The phrase "integrally formed" means that the partition wall 19 and the connecting portion 20 are not formed by joining multiple elements, but are formed from a single material as part or as a whole of a single object by machining or the like. At least one of the partition wall 19 and the connecting portion 20 may be formed separately and then joined.

[0021] As shown in Figure 1, the partition wall 19 is a thin plate that separates the first space A1 in the case 14 where the connector 18 is housed from the second space A2 in which other specified components are housed. In this example, the heat-generating component 17 is housed in the second space A2 as one of the specified components, but the heat-generating component 17 may be housed in the first space A1 together with the connector 18. As shown in Figure 2, the connecting portion 20 is a thin plate that connects the partition wall 19 and the case 14.

[0022] The partition wall 19 has an inclination angle α that slopes upward from its base edge 19a, which is located on the printed circuit board 15 side, toward the first space A1 where the connector 18 is housed. The inclination angle α is set appropriately according to the volume of the case 14 and the number of lead components 17. As shown in Figure 3, the heat-generating component 17 is attached to the back surface of the partition wall 19, that is, the inclined surface 19b of the partition wall 19 facing the second space A2 (Figure 2), via a fastening member 21.

[0023] As the fastening member 21, for example, an adhesive sheet is used, but screws, crimping parts, etc. may also be used. For example, the heat-generating component 17 can be screwed to the partition wall 19 using a burring tap, which is a hole that has been burred in a part of the partition wall 19 and then tapped. A part of the partition wall 19 can be cut out, and the area around the heat-generating component 17 can be crimped in multiple places. As shown in Figure 2, the lead wires 17a of the heat-generating component 17 are mounted in a state where they are inserted into the substrate 15.

[0024] The connecting portion 20 has a flat plate portion 22 and a pair of side walls 23, 23 as shown in Figure 4. The flat plate portion 22 is connected to the upper edge of the partition wall 19 and is a flat plate that is parallel to and in contact with the ceiling surface 14a inside the case 14 in Figure 2. The flat plate portion 22 is a heat dissipation path that releases heat from the heat-generating component 17 to the case 14. In this example, the flat plate portion 22 is in direct contact with the ceiling surface 14a inside the case 14, but it may also be a structure that is indirectly in contact with the ceiling surface 14a inside the case 14 via a heat dissipation sheet (not shown). The surface area and thickness of the flat plate portion 22 are set appropriately according to the amount of heat generated by the heat-generating component 17, for example.

[0025] As shown in Figure 4, the pair of side walls 23, 23 are trapezoidal vertical plates extending toward the substrate 15 (Figure 2) from both side edges of the partition wall 19 and the flat plate portion 22. Multiple fixing protrusions 23a are provided on the lower end edge of each side wall 23, projecting downward at regular intervals in the longitudinal direction. As shown in Figure 2, the substrate 15 has through-holes into which the multiple fixing protrusions 23a are fitted. The pair of side walls 23, 23 are fixed to the substrate 15 by fitting the multiple fixing protrusions 23a into the corresponding through-holes and soldering them.

[0026] As shown in Figure 1, the connector 18 is covered by the partition wall 19, the connecting portion 20, and a part of the case 14. Specifically, the connector 18 is covered by the partition wall 19, the flat plate portion 22, the pair of side walls 23, 23, and of the case 14, the side of the partition wall 19 facing the front (the side facing the first space A1), the upper portion connected to this side, both side portions, and the lower portion. The upper portion, both side portions, and the lower portion of the case 14 are the parts of the case 14 that extend from the aforementioned side to the edges 23b of each side wall 23 shown in Figure 2.

[0027] <Effects and Effects> According to the mounting structure of the heat-generating component 17 described above, the heat-generating component 17 is attached to the partition wall 19 of the component mounting plate 16, and a connecting portion 20 is provided to connect the partition wall 19 and the case 14. Therefore, heat from the heat-generating component 17 can be dissipated to the case 14 through the connecting portion 20. The partition wall 19 and connecting portion 20 of the component mounting plate 16 and a part of the case 14 cover the connector 18.

[0028] In this way, the component mounting plate 16 is used as a shielding material, and the component mounting plate 16 as a shielding material and a part of the case 14 work together to block noise radiated from the connector 18. Therefore, compared to conventional technology, the heat dissipation of the heat-generating component 17 can be improved and the EMC performance can be improved. Because a part of the component mounting plate 16 is used as a heat dissipation path, the distance between the heat-generating component 17 and the connector 18 can be made narrower than in the conventional structure (Figure 15). This makes it possible to shorten the pattern wiring on the circuit board 15 and make effective use of the mounting area of ​​the circuit board 15.

[0029] As shown in Figure 3, the heat-generating component 17 is attached to the inclined surface 19b of the partition wall 19, making it easier to attach the heat-generating component 17 than if it were attached to a vertical plate-shaped partition wall. Furthermore, since the inclined surface 19b of the partition wall 19 has a larger surface area than a vertical plate-shaped partition wall, there are fewer constraints on the size of the heat-generating component 17. Therefore, the design flexibility of the mounting structure for the heat-generating component 17 can be increased.

[0030] Since the heat-generating component 17 is attached to the partition wall 19 via a fastening member 21, the mounting structure of the heat-generating component 17 can be simplified, and manufacturing costs can be reduced. If an adhesive sheet is used as the fastening member 21, the cycle time for attaching the heat-generating component 17 to the partition wall 19 can be shortened compared to other mounting structures. If a screw is used as the fastening member 21, the heat-generating component 17 can be attached to the partition wall 19 more firmly than with other mounting structures. If a crimped portion with a cutout in part of the partition wall 19 is used as the fastening member 21, the number of parts can be reduced compared to other mounting structures, and the overall structure can be simplified.

[0031] <Regarding other embodiments> In the following description, parts corresponding to matters previously described in each embodiment will be denoted by the same reference numerals, and redundant explanations will be omitted. When only a part of the configuration is described, the other parts of the configuration will be the same as those in the previously described embodiment unless otherwise specified. Identical configurations will produce the same effects. Not only are combinations of the parts specifically described in each embodiment possible, but partial combinations of embodiments are also possible, provided that there are no particular problems with the combination.

[0032] [Second Embodiment] <Press-fit connection type: Figures 5-8> As shown in Figure 5, the component mounting plate 16A may be formed in an L-shape in cross-section as shown in Figure 7 by the partition wall 19A and the connecting portion 20A. As shown in Figure 6, the connecting portion 20A is a flat plate that is joined to the ceiling surface 14a (Figure 7) inside the case 14 by welding or the like. As shown in Figure 7, the partition wall 19A is a vertical plate extending from the upper edge to the lower edge 19Aa, with the lower edge 19Aa facing the substrate 15 with a predetermined gap between them. The substrate 15 and the motor terminal (terminal of the electric actuator) 11b are electrically connected by the press fit 24 shown in Figure 8.

[0033] As shown in Figure 7, in a structure where the joint 20A of the component mounting plate 16A is joined to the case 14, the heat-generating component 17 is fixed to the case 14 via the component mounting plate 16A. Therefore, it is not possible to solder the motor terminals 11b coming out of the motor side. Normally, the case 14 is closed after soldering the motor terminals 11b. However, by using the press-fit 24, the circuit board 15 and the motor terminals 11b are electrically connected.

[0034] In this case, assembly can be simplified compared to a configuration where the circuit board and motor terminals are soldered together, for example. Since the component mounting plate 16A is formed in an L-shape in cross-section by the partition wall 19A and the connecting portion 20A, the component mounting plate 16A can be simplified compared to the component mounting plate 16 (Figure 4) which includes the aforementioned pair of side walls, thereby reducing manufacturing costs. In addition, it provides the same effects as the embodiments described above.

[0035] <Connector connection type: Figures 9-10> As shown in Figures 9 and 10, the circuit board 15 and the motor terminals (terminals of the electric actuator) 11b may be electrically connected by a connector 25. The connector 25 is located on the outside of the case 14. The configuration other than the connector 25 is the same as that of the press-fit connection type. This connector connection type simplifies assembly compared to a configuration in which the circuit board 15 and the motor terminals 11b are soldered, for example. It also provides the same advantages and disadvantages as the embodiments described above.

[0036] [Third Embodiment] As shown in Figure 11 or Figure 12, the case 14 and the connecting portion 20A of the component mounting plate 16A may be integrally constructed. Even in this integrated case, the heat-generating component 17 is fixed to the case 14, making it impossible to solder the motor terminals 11b coming out of the motor 11. However, by using the press-fit 24 in Figure 11 or the connector 25 in Figure 12, the circuit board 15 and the motor terminals 11n can be electrically connected, simplifying assembly. The connector 25 is located on the outside of the case 14. When the case 14 and the connecting portion 20A of the component mounting plate 16A are integrally constructed, the number of parts and assembly man-hours can be reduced compared to a structure where the case and the connecting portion are separate. This reduces manufacturing costs.

[0037] It is also possible to apply the mounting structure for the heat-generating component according to any of the embodiments to an electric actuator in which the actuator body and the control device that controls the actuator body are electrically connected in a separate structure. The heat-generating component is not limited to semiconductor switching elements; any element that generates heat according to a command value is sufficient. Since part of the case covers the connector, the distance between the component mounting plate and the connector may be greater than the distance in each embodiment. Electric actuators may be mounted on industrial machinery other than vehicles.

[0038] While embodiments of the present invention have been described above, the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0039] 14…Case, 15…Circuit board, 16,16A…Component mounting plate, 17…Heat-generating component, 18…Connector, 19,19A…Partition wall, 20,20A…Connecting part, 21…Fastening member, 24…Press fit, 25…Connector

Claims

1. A component mounting plate on which heat-generating components are attached, The circuit board comprises a connector, a component mounting plate, and a case for housing the heat-generating component. The component mounting plate includes a plate-shaped partition wall that separates the space in the case where the connector is housed from the space where other specified components are housed, and a connecting portion that connects the partition wall to the case, the heat-generating component is attached to the partition wall, and the connector is covered by the partition wall, the connecting portion and a part of the case. The aforementioned partition wall has an inclination angle that slopes upward from the base edge located on the substrate side toward the space where the connector is housed, in a mounting structure for a heat-generating component.

2. A mounting structure for a heat-generating component according to claim 1, wherein the heat-generating component is attached to the partition wall via a fastening member.

3. A mounting structure for a heat-generating component according to claim 1 or claim 2, wherein the case and the connecting portion are integrally configured.

4. A mounting structure for a heat-generating component according to claim 1 or claim 2, wherein the substrate and the terminals of the electric actuator are electrically connected by a press fit or connector.

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