Electronic control unit

Abstract

To provide an electronic control device capable of securely connecting two housing members, constituting a metallic housing, electrically by bringing opposed surfaces into contact with each other.SOLUTION: An electronic control device comprises a printed wiring board on which an electronic component is mounted and a metallic housing which houses the printed wiring board. The housing comprises a first housing member which has a first flange part where a first opposed surface is formed and a second housing member which has a second flange part where a second opposed surface arranged opposite the first opposed surface is formed, a projection part which protrudes from one opposed surface between the first opposed surface and second opposed surface is formed on the opposed surface, and the first opposed surface and second opposed surface come into contact with each other on the opposite side from the projection part.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an electronic control device.

Background Art

[0002] For an electronic control device mounted in an engine room, there are many requirements such as waterproofness, heat resistance, corrosion resistance, shock resistance, and EMC (Electromagnetic Compatibility). In addition, an electronic control device (in-vehicle electronic control device) mounted on a vehicle is required to have a sealed structure in addition to the above-mentioned requirements. Since the inside of the engine room is strongly affected by the vehicle environment, an electronic control device mounted in the engine room requires a particularly high sealing structure. In such a case, a major factor affecting the electronic control device in the engine room is the pressure fluctuation applied to the electronic control device.

[0003] The pressure applied to the electronic control device fluctuates when the altitude of the current position of the vehicle changes or the temperature inside the engine room changes. In order to cope with such pressure fluctuations, for example, it is conceivable to attach a breathing filter to the housing of the electronic control device. However, attaching a breathing filter to the housing of the electronic control device makes it impossible to meet the requirement of making the electronic control device have a sealed structure. In addition, the housing of the electronic control device is required to be made of metal so as to withstand the load applied to the housing due to pressure fluctuations.

[0004] The electronic control device has a structure in which a printed wiring board is housed inside the housing. Various electronic components are mounted on the printed wiring board. In addition, the number of electronic components mounted on the printed wiring board is increasing with the high functionality of the vehicle. For this reason, the electronic control device is becoming larger and heavier.

[0005] Among the performance requirements for electronic control units installed in the engine compartment, the demands for waterproofing and corrosion resistance are particularly stringent. Therefore, electronic control units must have a structure that does not compromise waterproofing or corrosion resistance. When mounting electronic control units in the engine compartment, brackets are used. In this case, it is necessary to ensure a large contact area between the bracket and the electronic control unit so that the larger and heavier electronic control unit can be mounted even in the harsh environment of the engine compartment. In order to ensure a large contact area between the bracket and the electronic control unit, a flange portion is provided on the outer circumference of the housing of the electronic control unit, and the bracket is attached to the electronic control unit by gripping this flange portion. In such cases, the outer end surface of the flange portion must be flush (flat) to prevent the sealing material that seals the flange portion in an airtight state from flowing out onto the contact surface with the bracket.

[0006] Furthermore, in electronic control units mounted in the engine compartment, the printed circuit board (PCB) protected by the enclosure must also satisfy electrical requirements. The PCB has ground (GND) wiring that is electrically connected (conductive) to the metal enclosure. In this case, the electrical resistance between the PCB's ground and the enclosure must be between 470kΩ and 1MΩ. In addition, the PCB of the electronic control unit must be protected from static electricity applied to the electronic control unit from the outside, and from radiated noise generated both inside and outside the electronic control unit. If external noise enters the electronic control unit, that noise may reflect off the inner surface of the enclosure and adversely affect the electronic control unit.

[0007] On the other hand, to counteract radiated noise generated inside the electronic control unit, it is necessary to dissipate the charge accumulated in the casing to the outside of the electronic control unit via the ground of the printed circuit board. In order to dissipate the aforementioned radiated noise to the outside of the electronic control unit, it is necessary to connect the metal casing and the ground of the printed circuit board with the low electrical resistance mentioned above. The casing of the electronic control unit is constructed by combining two casing members to form a space for housing the printed circuit board inside the casing. The printed circuit board is attached to one of the casing members with metal screws. Therefore, one casing member and the printed circuit board can be connected electrically via the screws. However, there is no point to connect the printed circuit board to the other casing member. Therefore, in order to connect the metal casing and the ground of the printed circuit board with the low electrical resistance mentioned above, the two casing members must be connected electrically to each other.

[0008] Conventionally, a configuration has been adopted in which flange portions are formed on the outer periphery of one housing member and the outer periphery of the other housing member, and opposing surfaces are formed on each flange portion, and these opposing surfaces are brought into contact with each other to establish electrical conductivity between the two housing members (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] International Publication No. 2021 / 260992 [Overview of the project] [Problems that the invention aims to solve]

[0010] In recent years, the size of in-vehicle electronic control units has increased by about 1.5 times compared to conventional electronic control units, for example, with dimensions of 260mm x 240mm. As a result, warping is more likely to occur in the housing components during the manufacturing process, and this warping may prevent the opposing surfaces of the flanges from making contact.

[0011] The object of the present invention is to provide an electronic control device that can reliably establish electrical conductivity between two housing members constituting a metal housing through contact between opposing surfaces. [Means for solving the problem]

[0012] To solve the above problems, for example, the configuration described in the claims can be adopted. The present invention includes several means for solving the above problems, but one example is an electronic control device comprising a printed circuit board on which electronic components are mounted and a metal housing for housing the printed circuit board. The housing comprises a first housing member having a first flange portion on which a first opposing surface is formed, and a second housing member having a second flange portion on which a second opposing surface is formed and positioned opposite the first opposing surface. A convex portion is formed on at least one of the first and second opposing surfaces in a manner that protrudes from the opposing surface, and the first and second opposing surfaces are in contact on the side opposite to the convex portion. [Effects of the Invention]

[0013] According to the present invention, two housing members constituting a metal housing can be reliably electrically connected by contact between their opposing surfaces. Other issues, configurations, and effects not mentioned above will be clarified by the following description of the embodiments. [Brief explanation of the drawing]

[0014] [Figure 1] This is an exploded perspective view of the electronic control device according to the first embodiment, viewed from an oblique angle above. [Figure 2] This is an exploded perspective view of the electronic control device according to the first embodiment, viewed from a diagonal downward angle. [Figure 3] This is a partial cross-sectional view of an electronic control device according to the first embodiment. [Figure 4] This is a schematic diagram showing the arrangement of opposing surfaces. [Figure 5] This is a side view of the electronic control device according to the first embodiment. [Figure 6] It is a plan view with a part of the base included in the electronic control device according to the first embodiment enlarged. [Figure 7] It is a sectional view taken along the line A-A in FIG. 6. [Figure 8] It is a sectional view taken along the line B-B in FIG. 6. [Figure 9] It is a view with a part of the base included in the electronic control device according to the second embodiment enlarged. [Figure 10] It is a sectional view taken along the line C-C in FIG. 9. [Figure 11] It is a sectional view for explaining a modification example of the second embodiment. [Figure 12] It is a view with a part of the base included in the electronic control device according to the third embodiment enlarged. [Figure 13] It is a sectional view taken along the line D-D in FIG. 12. [Figure 14] It is a longitudinal sectional view with a main part of the electronic control device according to the fourth embodiment enlarged.

MODE FOR CARRYING OUT THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this specification and the drawings, elements having substantially the same function or configuration are denoted by the same reference numerals, and duplicate descriptions are omitted. The electronic control device described below is mounted on a vehicle, for example, to control an engine, a transmission, and the like.

[0016] <First Embodiment> FIG. 1 is an exploded perspective view of the electronic control device according to the first embodiment viewed obliquely from above. FIG. 2 is an exploded perspective view of the electronic control device according to the first embodiment viewed obliquely from below. FIG. 3 is a partial sectional view of the electronic control device according to the first embodiment.

[0017] As shown in FIGS. 1 to 3, the electronic control device 1 includes a housing 2, a printed wiring board 3, a base 4, a sealing material 5, a plurality (three in the illustrated example) of connectors 6, and a connector sealing material 51.

[0018] The housing 2 and base 4 are components that make up the metal housing 10. The housing 2 and base 4 are preferably made of aluminum. The housing 2 is preferably formed by an aluminum die-casting method using a mold. The same applies to the base 4. The housing 2 is provided as an example of a first housing component, and the base 4 is provided as an example of a second housing component. The housing 2 has the same number of openings 9 as the connector 6.

[0019] The enclosure 10 protects the printed circuit board 3 from water and foreign matter. The enclosure 10 also functions to dissipate heat generated by the electronic components mounted on the printed circuit board 3 and to shield against noise generated within the enclosure 10 or external noise. Therefore, if the enclosure 10 were constructed from a thermoplastic resin such as PBT (polybutylene terephthalate), the heat dissipation function would be insufficient, and the noise shielding function would not be achieved. Thus, the enclosure 10 must be made of metal. Furthermore, high-performance electronic control devices for engines need to protect their electronic components not only from external noise but also from noise generated by specific electronic components on the printed circuit board 3 (for example, electronic components with CPUs that operate at high frequencies), i.e., from internal noise. Therefore, if a resin enclosure were used, the noise shielding effect would not be achieved, potentially leading to malfunctions of the electronic components.

[0020] The housing 10 is formed in a rectangular shape in plan view. In this embodiment, as an example, the housing 10 is formed in a rectangular shape in plan view. The lengths of the long and short sides of the housing 10 are, for example, 260 mm x 240 mm. This size is large for an electronic control unit 1 to be placed within the engine rule. The housing 10 forms a space capable of housing the printed circuit board 3 (hereinafter also referred to as the "board storage space") by assembling the housing 2 and the base 4 together.

[0021] The housing 2 has a first flange portion 11, and the base 4 has a second flange portion 12. The first flange portion 11 is formed on the outer circumference of the housing 2, extending around its entire circumference (all four sides). The second flange portion 12 is formed on the outer circumference of the base 4, extending around its entire circumference. As shown in Figure 3, the first flange portion 11 and the second flange portion 12 are positioned facing each other when the housing 2 and the base 4 are assembled.

[0022] Furthermore, the housing 2 has a first circumferential wall portion 14, and the base 4 has a second circumferential wall portion 15. The first circumferential wall portion 14 is formed integrally with the first flange portion 11, and the second circumferential wall portion 15 is formed integrally with the second flange portion 12. The first flange portion 11 is positioned to protrude outward from the outer surface of the first circumferential wall portion 14, and the second flange portion 12 is positioned to protrude outward from the outer surface of the second circumferential wall portion 15. The first circumferential wall portion 14 and the second circumferential wall portion 15 form a substrate storage space when the housing 2 and the base 4 are assembled. At that time, the first circumferential wall portion 14 is positioned outside the second circumferential wall portion 15. The lower end portion 14a of the first circumferential wall portion 14 is positioned to protrude downward from the first flange portion 11.

[0023] A first groove 41 and a second groove 42 are formed on the outside of the second peripheral wall portion 15. The first groove 41 is a groove for filling with sealing material 5. The first groove 41 is formed adjacent to the second peripheral wall portion 15. The second peripheral wall portion 15 serves to block the sealing material 5 when it is applied to the first groove 41 during the manufacturing process of the electronic control device 1. The second groove 42 is a groove for accommodating leaked sealing material 5 if it leaks from the first groove 41 during the manufacturing process of the electronic control device 1. The first groove 41 is formed around the entire circumference of the second flange portion 12 so as to surround the substrate storage space, and the second groove 42 is formed around the entire circumference of the second flange portion 12 so as to surround the first groove 41. The first groove 41 and the second groove 42 are formed on the upper surface side of the second flange portion 12. The second groove 42 is formed on the outer circumference side of the second flange portion 12, compared to the first groove 41. The first groove 41 is wider than the second groove 42. Also, the first groove 41 is deeper than the second groove 42.

[0024] The first flange portion 11 is positioned so as to overlap with the second flange portion 12 when the electronic control device 1 is viewed from above. As shown in Figure 3, the first flange portion 11 has a first opposing surface 31, and the second flange portion 12 has a second opposing surface 32. The first opposing surface 31 and the second opposing surface 32 are positioned facing each other. The second groove portion 42 is formed in a concave shape on the second opposing surface 32. The upper end portion 15a of the second peripheral wall portion 15 is positioned higher than the second opposing surface 32.

[0025] The printed circuit board 3 is housed inside the housing 10. The printed circuit board 3 is attached to the housing 2 by metal screws (not shown). At least four holes 3a for screw fastening are formed in the four corners of the printed circuit board 3. The holes 3a in the printed circuit board 3 are electrically connected to the ground line (not shown) of the printed circuit board 3. Specifically, an electrode pad connected to the ground line is formed around at least one of the multiple holes 3a provided in the printed circuit board 3, and the hole 3a is formed in the area where this electrode pad is formed. On the other hand, the housing 2 has a board mounting portion 16 (Figure 2) for attaching the printed circuit board 3, and screw holes 17 are formed in this board mounting portion 16. The metal screws then engage with the screw holes 17 in the housing 2 through the holes 3a in the printed circuit board 3 and are tightened in this state. At that time, the heads of the screws are pressed against the electrode pads by the tightening force of the screws themselves. Therefore, the ground line of the printed circuit board 3 is electrically connected to the housing 2 via the screws.

[0026] In addition to the connector 6 mentioned above, electronic components (not shown) are mounted on the printed circuit board 3. A heat dissipation pad 7 is also formed on the printed circuit board 3. The heat dissipation pad 7 is a pad that dissipates the heat generated by the electronic components mounted on the printed circuit board 3 to the housing 2. On the other hand, a heat dissipation base 18 (Figure 2) is formed on the housing 2 corresponding to the heat dissipation pad 7. The heat dissipation pad 7 is bonded to the heat dissipation base 18 of the housing 2 with a thermally conductive adhesive (not shown). As a result, the heat generated by the electronic components is transferred to the housing 2 through the heat dissipation pad 7 and the heat dissipation base 18 and released from the outer surface of the housing 2.

[0027] The sealant 5 seals the mating portion between the housing 2 and the base 4. A silicone adhesive is preferred as the sealant 5. Silicone resin has advantages such as excellent adhesion to metals, resistance to saltwater and water, and sufficient heat and weather resistance to withstand harsh environments exposed to high temperatures, such as engine compartments. However, the sealant 5 is not limited to silicone resin; for example, epoxy resin may also be used.

[0028] In the manufacturing process of the electronic control unit 1, first, a printed circuit board 3 on which electronic components including a connector 6 are mounted is attached to the housing 2 by screw fastening. Next, a sealing material 5 is applied to the first groove 41 of the base 4.

[0029] Next, the housing 2 and the base 4 are assembled. At this time, with the first opposing surface 31 of the housing 2 and the second opposing surface 32 of the base 4 facing each other, the lower end portion 14a of the first peripheral wall portion 14 is embedded in the sealant 5 in the second groove portion 42. At this time, depending on the amount of sealant 5 applied, the sealant 5 may overflow from the first groove portion 41. The sealant 5 that overflows from the first groove portion 41 is contained in the second groove portion 42. By assembling the housing 2 and the base 4 in this manner, the outer circumference of the housing 10 is sealed all around by the sealant 5. Therefore, the electronic control device 1 can be made into a sealed structure.

[0030] The electronic control unit 1 according to this embodiment is intended to be mounted in the engine compartment. Therefore, in order to protect the printed circuit board 3 from saltwater and foreign matter, the housing 10 needs to be sealed as described above. However, when the housing 10 is sealed, the pressure inside the housing 10 fluctuates due to temperature changes, etc. Therefore, if the internal pressure of the electronic control unit 1 becomes higher than the external pressure, a force acts to bend the housing 2 and base 4 that make up the housing 10 outward, and the housing 2 and base 4 deform under this force. In this case, the amount of deformation of the housing 2 and base 4 is greatest at the center of the long side of the electronic control unit 1. Therefore, the sealing material 5 needs to have sufficient adhesive strength to withstand the deformation of the housing 2 and base 4. In addition, since the sealing material 5 generates gas when curing, this gas needs to be discharged to the outside of the electronic control unit 1.

[0031] The electronic control unit 1 according to this embodiment is designed to be 1.5 times larger in planar size than a typical electronic control unit, meaning it is considerably larger. Furthermore, the electronic control unit 1 is mounted in the engine compartment of a vehicle or the like using a bracket (not shown). In this case, in order to grip the outer periphery of the electronic control unit 1 with the bracket, it is necessary to ensure that the overlapping dimension L (Figure 3) of the first flange portion 11 and the second flange portion 12 is 10 mm or more.

[0032] Furthermore, the mass of the electronic control unit 1 increases with its size. In such a large and massy electronic control unit 1, the area of ​​the first opposing surface 31 of the first peripheral wall portion 14 and the area of ​​the second opposing surface 32 of the second peripheral wall portion 15 increase due to the larger outer circumference. Therefore, when manufacturing the housing 2 and base 4, the flatness of the first opposing surface 31 and the second opposing surface 32 increases. Consequently, the first opposing surface 31 and the second opposing surface 32 have surfaces with minute irregularities, as shown in Figure 4. Also, as mentioned above, as the electronic control unit 1 becomes larger, warping is more likely to occur in the housing 2 and base 4. As a result, when the housing 2 and base 4 are assembled, a gap is created between the first opposing surface 31 and the second opposing surface 32, as shown in Figure 4, making it difficult to electrically connect (conductively) the housing 2 and base 4 by contact between the opposing surfaces. The housing 2 and base 4 serve to protect the electronic components on the printed circuit board 3 from noise and static electricity. However, if the first opposing surface 31 and the second opposing surface 32 are not in contact, the electronic components may not be adequately protected from noise and static electricity. Furthermore, the sealing material 5 that seals the outer periphery of the housing 2 and base 4 is an insulating material and therefore does not contribute to the electrical connection between the housing 2 and base 4.

[0033] The connector 6 is mounted on the printed circuit board 3 while being electrically connected to the wiring pattern of the printed circuit board 3. Furthermore, when the printed circuit board 3 is mounted in the housing 2, the connector 6 is fitted into the opening 9 of the housing 2 via the connector seal material 51. The connector seal material 51 provides a waterproof function by sealing the mating portion between the opening 9 of the housing 2 and the connector 6. The connector 6 is mounted in the X direction shown in Figure 1, offset in the x1 direction from the center of the printed circuit board 3. Also, the connector 6 has a larger mass than other electronic components mounted on the printed circuit board 3. Therefore, the center of gravity of the printed circuit board 3 with three connectors 6 attached will be biased towards the x1 direction in the X direction.

[0034] Figure 5 is a side view of the electronic control device according to the first embodiment. Figure 6 is an enlarged plan view of a part of the base of the electronic control device according to the first embodiment. Figure 7 is a cross-sectional view of AA in Figure 6, and Figure 8 is a cross-sectional view of BB in Figure 6.

[0035] As shown in Figures 5 to 8, a protrusion 8 is interposed between the first flange portion 11 of the housing 2 and the second flange portion 12 of the base 4. The housing 2 and the base 4 are inclined at an angle θ relative to each other due to the interposition of this protrusion 8. In Figure 5, for the sake of explanation, the protrusion of the protrusion 8 is exaggerated, and the inclination angle θ between the housing 2 and the base 4 is shown as larger.

[0036] The protrusions 8 are provided on the second opposing surface 32 of the second flange portion 12 of the base 4. Furthermore, one protrusion 8 is provided at each of the two corners of the base 4 that are not diagonally opposite each other. In other words, the protrusions 8 are located at both ends of one side of the base 4 that constitutes the housing 10. The protrusions 8, like the second peripheral wall portion 15, the first groove portion 41, and the second groove portion 42, are integrally formed with the base 4. For example, when the base 4 is manufactured by aluminum die-casting, the protrusions 8 can be formed integrally with the base 4 by forming recesses corresponding to the protrusions 8 in the molding die.

[0037] The protrusion 8 is formed in a cylindrical shape and protrudes from the second opposing surface 32 of the second flange portion 12. The protrusion dimension Lh of the protrusion 8 relative to the second opposing surface 32 (Figure 7) is greater than the flatness of the second opposing surface 32. Therefore, even if minute irregularities exist on the second opposing surface 32, the protrusion 8 will protrude with a protrusion dimension Lh that is larger than the dimension of these irregularities. Preferably, the protrusion dimension Lh of the protrusion 8 is 0.2 mm or more and 0.7 mm or less.

[0038] Guide grooves 43 (Figure 6) are formed on both sides of the protrusion 8. The guide grooves 43 are connected to the second groove 42. Additionally, auxiliary grooves 44 (Figure 6) are formed at the corners of the second groove 42. The guide grooves 43 guide the sealant 5 that overflows from the first groove 41 to the second groove 42. The second opposing surface 32 forms a single plane except for the portions of the second groove 42, the guide grooves 43, and the auxiliary grooves 44.

[0039] The protrusion 8 is located on the x2 side, which is the side furthest from the center of gravity of the housing 2 in the X direction shown in Figure 5. Specifically, the protrusion 8 is located on the x2 edge of the base 4 in the X direction. As mentioned above, the position of the center of gravity of the housing 2 is defined when the printed circuit board 3 with the connector 6 mounted on it is attached to the housing 2. When the printed circuit board 3 with the connector 6 mounted on it is attached to the housing 2, the mass balance of the housing 2 in the X direction is such that the mass ratio on the x1 side is greater than the mass ratio on the x2 side. Therefore, when the housing 2 is assembled by placing it over the base 4, the load applied from the housing 2 to the base 4 by the total mass of the housing 2, including the printed circuit board 3 and the connector 6, is greater on the x1 side than on the x2 side.

[0040] Therefore, as shown in Figure 5, when the housing 2 is tilted at an angle θ by the protrusion 8 relative to the horizontally placed base 4, the load applied from the housing 2 to the base 4 increases at the end portion 20 of the housing 10 opposite the protrusion 8. In other words, at the end portion 20 of the housing 10, the first flange portion 11 of the housing 2 is pressed with a strong force against the second flange portion 12 of the base 4.

[0041] In the electronic control device 1 according to the first embodiment described above, since a protrusion 8 is provided on the second opposing surface 32 of the base 4, when assembling the housing 2 and the base 4, the second opposing surface 32 of the housing 2 abuts against the tip of the protrusion 8. Therefore, the housing 2 is tilted at an angle θ with respect to the base 4. As a result, at the end edge 20 of the housing 10 located on the opposite side of the protrusion 8 in the X direction, the first opposing surface 31 of the first flange portion 11 and the second opposing surface 32 of the second flange portion 12 are in contact. This ensures that the housing 2 and the base 4 constituting the housing 10 are reliably electrically connected by the contact between the opposing surfaces 31 and 32. Therefore, the function of protecting the electronic components on the printed circuit board 3 housed inside the housing 10 from noise, static electricity, etc. can be enhanced.

[0042] Furthermore, the protrusion 8 is integrally formed with the base 4. Therefore, when the protrusion 8 is provided on the housing 10, it does not lead to an increase in the number of parts or manufacturing man-hours. Also, the protrusion 8 is made of metal, just like the other parts of the base 4. Therefore, the housing 2 and the base 4 can be electrically connected via the protrusion 8.

[0043] Furthermore, the protrusion dimension Lh of the convex portion 8 is greater than the flatness of the second opposing surface 32 of the second flange portion 12. Therefore, when assembling the housing 2 and the base 4, the tip of the convex portion 8 can be reliably brought into contact (butted) with the second opposing surface 32 of the housing 2.

[0044] Furthermore, the protrusion 8 is positioned on the side furthest from the center of gravity of the housing 2 to which the printed circuit board 3 is attached. Therefore, at the edge portion 20 of the housing 10, the second flange portion 12 of the base 4 can be pressed against the first flange portion 11 of the housing 2 with strong force by utilizing the imbalance in the mass balance of the housing 2. As a result, at the edge portion 20 of the housing 10, the contact pressure between the first opposing surface 31 and the second opposing surface 32 can be increased, resulting in a more stable contact state.

[0045] Furthermore, the protrusions 8 are positioned at both ends of one side of the housing 10. Therefore, on the end side 20 of the housing 10 opposite to the protrusions 8, the first opposing surface 31 and the second opposing surface 32 can be brought into contact along the entire length of the end side 20.

[0046] Furthermore, by adopting a configuration with a protrusion 8, a gap is formed between the first opposing surface 31 of the first flange portion 11 and the second opposing surface 32 of the second flange portion 12 due to the relative inclination of the housing 2 and the base 4 described above. This makes it easier for the gas generated when the sealing material 5 hardens to escape to the outside of the electronic control device 1.

[0047] <Second Embodiment> Next, an electronic control device according to the second embodiment will be described. The electronic control device according to the second embodiment differs from the electronic control device according to the first embodiment in the configuration of the base (second housing member), which is one of the components of the metal housing.

[0048] Figure 9 is an enlarged view of a part of the base of the electronic control device according to the second embodiment. Figure 10 is a cross-sectional view of CC in Figure 9. As shown in Figures 9 and 10, the second opposing surface 32a along the long side of the base 4 protrudes upward by a predetermined projection dimension Lh compared to the other second opposing surfaces 32. In other words, the second opposing surface 32a constitutes a protrusion that extends from the second opposing surfaces 32. The second opposing surface 32a is formed to be continuous along one side of the housing 10 (base 4).

[0049] Furthermore, the second opposing surface 32a is integrally formed with the base 4, similar to the protrusion 8 in the first embodiment. Since the second opposing surface 32a is formed from the same metal as the base 4 (for example, aluminum), it is electrically conductive. The protrusion dimension Lh of the second opposing surface 32a is set to be the same as the protrusion dimension Lh of the protrusion 8 in the first embodiment.

[0050] In the second embodiment, the second opposing surface 32a of the base 4 is made to protrude more than the other second opposing surfaces 32 to form a convex portion. For the same reasons as in the first embodiment, the housing 2 and the base 4 can be reliably electrically connected by contact between the opposing surfaces 31 and 32. Furthermore, the second opposing surface 32a is formed to be continuous along one side of the housing 10. Therefore, on the side where the second opposing surface 32a as a convex portion is formed, an electrical connection point between the first opposing surface 31 and the second opposing surface 32 can be secured along the entire longitudinal direction of the second opposing surface 32a. In addition, the second opposing surface 32a is integrally formed with the base 4. Therefore, as in the first embodiment, the housing 2 and the base 4 can be electrically connected without increasing the number of parts or manufacturing man-hours. Other effects are omitted from the explanation as they overlap with those of the first embodiment.

[0051] In the second embodiment, the second opposing surface 32a along the long side of the base 4 is made to protrude more than the other second opposing surfaces 32 to form a convex portion, but the present invention is not limited to this. For example, as another example of the CC cross-sectional view in Figure 9, as shown in Figure 11, the second opposing surface 32b along the short side of the base 4 may be made to protrude more than the other second opposing surfaces 32 to form a convex portion. Also, although not shown, the second opposing surface 32 sandwiched between the two guide grooves 43 may be made to protrude more than the other second opposing surfaces 32 to form a convex portion.

[0052] Furthermore, protrusions may be formed at both ends of the second opposing surface 32 along the long or short side of the base 4. Alternatively, a protrusion may be formed at only one location (preferably in the middle) of the second opposing surface 32 along the long or short side of the base 4. This also applies to the protrusion 8 in the first embodiment described above, and to the embodiments described later.

[0053] <Third Embodiment> Next, an electronic control device according to the third embodiment will be described. The electronic control device according to the third embodiment differs from the electronic control device according to the first embodiment in the configuration of the base (second housing member), which is one of the components of the metal housing.

[0054] Figure 12 is an enlarged view of a part of the base of the electronic control device according to the third embodiment. Figure 13 is a cross-sectional view of the DD in Figure 12. As shown in Figures 12 and 13, tape material 85 is provided as a protrusion at the corner of the base 4. The tape material 85 is attached to the second opposing surface 32 sandwiched between two guide grooves 43. When the housing 2 and the base 4 are assembled, the tape material 85 is attached to the first opposing surface 31 of the housing 2.

[0055] The tape material 85 is made of a conductive tape, for example, a conductive double-sided tape. The conductive double-sided tape is a double-sided tape that uses an adhesive containing a conductive filler, such as carbon powder. In a configuration in which the tape material 85 is attached to the second opposing surface 32, the protruding dimension Lh (Figure 13) of the tape material 85 relative to the second opposing surface 32 corresponds to the thickness dimension of the tape material 85.

[0056] In the third embodiment, a protrusion is formed by a tape material 85 attached to the second opposing surface 32 of the base 4. For the same reasons as in the first embodiment, the housing 2 and the base 4 can be reliably electrically connected by contact between the opposing surfaces 31 and 32.

[0057] Furthermore, the tape material 85 is a separate component from the base 4. Therefore, the same effects as in the first embodiment can be obtained by reusing an existing (conventional) base 4 that does not have a protrusion. Also, since the tape material 85 is conductive, the housing 2 and the base 4 can be electrically connected via the tape material 85. In addition, since the tape material 85 is made of double-sided tape, the housing 2 and the base 4 can be temporarily fixed in place until the sealing material 5 hardens. Other effects will be omitted from the explanation as they overlap with those of the first embodiment.

[0058] <Fourth Embodiment> Next, an electronic control device according to the fourth embodiment will be described. The electronic control device according to the fourth embodiment differs from the electronic control device according to the first embodiment in the specific means for forming the protrusions. Figure 14 is an enlarged longitudinal cross-sectional view of the main part of the electronic control device according to the fourth embodiment. As shown in Figure 14, a portion 5a of the sealing material 5 protrudes between the first opposing surface 31 of the housing 2 and the second opposing surface 32 of the base 4. The portion 5a of the sealing material 5 is formed to protrude from the first opposing surface 31, for example, when the first opposing surface 31 is used as a reference. In other words, in the fourth embodiment, the protrusion is formed by the portion 5a of the sealing material 5.

[0059] One method for forming a protrusion using a portion 5a of the sealant 5 is, for example, when applying the sealant 5 to the first groove 41 of the base 4, a larger amount of sealant 5 should be applied to the area where the protrusion is to be formed, so that it overflows from the first groove 41. In this way, in the area where a larger amount of sealant 5 is applied, when the lower end portion 14a of the first peripheral wall 14 is embedded in the second peripheral wall 15, a portion 5a of the sealant 5 will overflow from the first groove 41. At this time, the thickness dimension t of the portion 5a of the sealant 5 is a factor that determines the protrusion dimension of the protrusion, so the pressing force of the housing 2 against the base 4 should be adjusted, for example, so that a portion 5a of the sealant 5 with an appropriate thickness dimension t remains between the first opposing surface 31 and the second opposing surface 32. After that, when the sealant 5 is hardened, a protrusion can be formed using a portion 5a of the sealant 5.

[0060] In the fourth embodiment, a protrusion is formed by a portion 5a of the sealing material 5. For the same reasons as in the first embodiment, the housing 2 and the base 4 can be reliably electrically connected by contact between the opposing surfaces 31 and 32. Furthermore, the sealing material 5 is a separate component from the base 4. For this reason, the same effects as in the first embodiment can be obtained by reusing an existing (conventional) base 4 that does not have a protrusion. Other effects will be omitted from the explanation as they overlap with those of the first embodiment.

[0061] <Examples of variations, etc.> It should be noted that the present invention is not limited to the embodiments described above, and includes various modifications. For example, although the embodiments described above are explained in detail to facilitate understanding of the present invention, the present invention is not necessarily limited to having all the configurations described in the embodiments described above. Furthermore, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. In addition, it is possible to delete a part of the configuration of each embodiment, add other configurations, or replace other configurations.

[0062] For example, in each of the embodiments described above, a protrusion is formed on the second opposing surface 32 of the base 4, but the present invention is not limited to this, and a protrusion may be formed on the first opposing surface 31 of the housing 2. Alternatively, protrusions may be formed on both the first opposing surface 31 and the second opposing surface 32. Furthermore, the protrusion may be provided at only one location (preferably in the middle) on any one side of the housing 10, at multiple locations along any one side, or continuously (linearly) along any one side. [Explanation of Symbols]

[0063] 1…Electronic control unit, 2…Housing (first housing component), 3…Printed circuit board, 4…Base (second housing component), 5…Sealing material, 5a…Part (protrusion), 8…Protrusion, 10…Housing, 11…First flange portion, 12…Second flange portion, 31…First opposing surface, 32…Second opposing surface, 32a, 32b…Second opposing surface (protrusion), 85…Tape material (protrusion)

Claims

1. An electronic control device comprising a printed circuit board on which electronic components are mounted, and a metal housing that houses the printed circuit board, The housing comprises a first housing member having a first flange portion on which a first opposing surface is formed, and a second housing member having a second flange portion on which a second opposing surface is formed and positioned opposite the first opposing surface. A convex portion is formed on at least one of the first opposing surface and the second opposing surface, such that it protrudes from the opposing surface. The aforementioned housing is formed in a rectangular shape in plan view, The aforementioned protrusion is formed to be continuous along one side of the housing, The aforementioned protrusion is attached to the first housing member and / or the second housing member. Electronic control unit.

2. The protruding dimension of the convex portion is greater than the flatness of the first opposing surface and / or the flatness of the second opposing surface. The electronic control device according to claim 1.

3. The printed circuit board is attached to the first housing member. The center of gravity of the first housing member to which the printed circuit board is attached is biased to one side in a predetermined direction. The protrusion is positioned on the side furthest from the center of gravity of the first housing member in the predetermined direction. The electronic control device according to claim 1.

4. The aforementioned housing is formed in a rectangular shape in plan view, The aforementioned protrusions are located at both ends of one side of the housing. The electronic control device according to claim 1.

5. The aforementioned protrusion has conductivity The electronic control device according to claim 1.

6. The aforementioned protrusion is formed by double-sided tape. The electronic control device according to claim 1 or 5.

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