Electronic control unit

Abstract

This electronic control device comprises a substrate, a protective member, a case, and a protruding part. The protective member is installed between a connector and an electronic component on the substrate. The case is formed from a base and a cover. The protruding part is disposed on the cover at a position facing the protective member and protrudes toward the substrate and the base. A recessed part is formed on one of the protruding part and the protective member, and the other of the protruding part and the protective member is inserted into the recessed part. The protruding part and the protective member are arranged so as to overlap each other in an outward view from an internal space of the case.

Description

Technical Field

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

Background Art

[0002] Automobiles are equipped with an electronic control device having electronic components for controlling the automobile. In recent years, the demand for advanced driver assistance systems (hereinafter referred to as ADAS) and autonomous driving (hereinafter referred to as AD) systems has increased, and the development of autonomous driving technology for automobiles has been accelerating. Then, in order to realize driving assistance systems such as collision damage reduction brakes and autonomous driving, high computing performance is required for the electronic control devices mounted on vehicles and the like. For this reason, an integrated circuit with a high operating frequency is incorporated in the electronic control device. Along with this, the high-frequency electromagnetic noise radiated by the electronic control device tends to increase, and it is necessary to suppress this below the reference value defined by laws in each country.

[0003] As a technique for preventing such electromagnetic wave noise from leaking to the outside, for example, there is one described in Patent Document 1. Patent Document 1 describes a technique including a main board, a connector disposed at a predetermined position of the main board, and a CPU disposed at a predetermined position of the main board. Further, Patent Document 1 describes that a metal substrate having conductivity disposed perpendicular to the plane of the main board is provided at a predetermined position between the connector and the CPU of the main board, and a bare chip is disposed on the metal substrate.

[0004] FIG. 9 is a cross-sectional view showing a conventional electronic control device. As shown in FIG. 9, a conventional electronic control device 300 has a substrate 101 on which electronic components 104 such as semiconductor components are mounted, a base 402 and a cover 401 constituting a housing, and a connector 102 mounted on the substrate 101. The cover 401 is provided with a protruding portion 410 protruding toward the substrate 101. Further, a metal substrate 505 is disposed perpendicular to the substrate 101 between the electronic component 104 and the connector 102 on the substrate 101.

Prior Art Documents

[0005] [Patent Document 1] Japanese Patent Application Publication No. 9-223895 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, with conventional technology, vibrations and other factors caused mechanical stress at the connection point between the electronic circuit board and the metal circuit board. Therefore, in connection methods where the metal circuit board is clamped with clip leads, there was a possibility that the metal circuit board could detach from the electronic circuit board. Furthermore, in connection methods using solder, solder cracks could occur, leading to electrical connection failures.

[0007] Furthermore, with conventional technology, it is difficult to position the metal substrate 505 perpendicular to the substrate 101 during manufacturing. Therefore, the gap x between the metal substrate 505 and the protrusion 410 had to be wide to avoid interference. As a result, conventional technology had the problem of not being able to sufficiently reduce the leakage of electromagnetic noise to the outside.

[0008] The objective of this invention is to provide an electronic control device that can reduce the leakage of electromagnetic noise to the outside of the enclosure, taking into consideration the above-mentioned problems. [Means for solving the problem]

[0009] To solve the above problems and achieve the objective, the electronic control device comprises a circuit board on which electronic components and connectors are mounted, a protective member, a housing, and a protrusion. The protective member is mounted between the electronic components and connectors on the circuit board. The housing consists of a base on which the circuit board is placed and a cover that covers the base on which the circuit board is placed. The protrusion is provided in the cover at a position opposite the protective member and protrudes toward the circuit board and base. A recess is formed in either the protrusion or the protective member, and the other part of the protrusion or protective member is inserted into the recess. When viewed from the inside of the housing toward the outside, the protrusion and the protective member are arranged to overlap. [Effects of the Invention]

[0010] According to the electronic control device with the above configuration, it is possible to reduce the leakage of electromagnetic noise to the outside of the enclosure. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view showing the circuit board of an electronic control device according to the first embodiment. [Figure 2] This is a cross-sectional view of an electronic control device according to a first embodiment. [Figure 3] This is an enlarged cross-sectional view showing the protruding portion and protective member of the electronic control device according to the first embodiment. [Figure 4] This is a perspective view showing a protective member of an electronic control device according to a second embodiment. [Figure 5] This is a perspective view showing a protective member of an electronic control device according to a third embodiment. [Figure 6] This is an enlarged cross-sectional view showing the protruding portion and protective member of the electronic control device according to the fourth embodiment. [Figure 7] This is an enlarged cross-sectional view showing the protruding portion and protective member of the electronic control device according to the fifth embodiment. [Figure 8] This is an enlarged cross-sectional view showing the protruding portion and protective member of the electronic control device according to the sixth embodiment. [Figure 9]It is a cross-sectional view showing a conventional electronic control device.

Embodiments for Carrying out the Invention

[0012] Hereinafter, embodiments of the electronic control device will be described with reference to FIGS. 1 to 8. In each figure, common members are denoted by the same reference numerals.

[0013] 1. First Embodiment Example First, the configuration of the electronic control device according to the first embodiment example (hereinafter referred to as "this example") will be described with reference to FIGS. 1 to 3. FIG. 1 is a plan view showing the substrate of the electronic control device, and FIG. 2 is a cross-sectional view showing the electronic control device.

[0014] The device shown in FIGS. 1 and 2 is an electronic control device mounted on an automobile and having an electronic circuit for controlling the automobile. As shown in FIGS. 1 and 2, the electronic control device 100 includes a substrate 101 on which electronic components 104 such as semiconductor components are mounted, a base 202 and a cover 201 constituting the housing, connectors 102 and 103 mounted on the substrate 101, and two protective members 105. The substrate 101 is housed in the base 202 and the cover 201. In addition, two protective members 105 are mounted on the substrate 101.

[0015] The substrate 101 is formed in a substantially flat plate shape. A plurality of fixing holes 101a are formed in the substrate 101. The substrate 101 is placed on one surface 202a of the base 202. The cover 201 is arranged so as to cover one surface of the base 202 on which the substrate 101 is placed. Then, the cover 201 is fixed to the base 202 by inserting fixing screws into the fixing holes 101a provided in the substrate 101. Note that the base 202 and the cover 201 constituting the housing are formed of a conductive material, for example, made of metal, or made of conductive resin or resin with plating on the surface.

[0016] Connectors 102 and 103 are mounted on one end of the substrate 101. The protective member 105 is disposed between the connectors 102 and 103 mounted on the substrate 101 and the electronic component 104. One of the two protective members 105, 105 is disposed near the connector 102, and the remaining protective member 105 is disposed near the connector 103. A fixing hole 101a into which a fixing screw is inserted is formed between the two protective members 105, 105 on the substrate 101.

[0017] The protective member 105 may be made of a conductive material or a material capable of absorbing electromagnetic waves, such as a copper plate, a conductive resin, a plated resin surface, or an electromagnetic wave absorber. The protective member 105 is electrically connected to the base 202 through a land (not shown) on the substrate 101.

[0018] The protective member 105 is formed, for example, in a substantially flat plate shape having a rectangular shape. As shown in FIG. 2, the length h in the height direction perpendicular to the mounting surface of the substrate 101 of the protective member 105 is set shorter than the length W in the width direction parallel to the mounting surface of the substrate 101 of the protective member 105 (W>h). That is, the protective member 105 is formed in a horizontally long shape.

[0019] The cover 201 constituting the housing covers the base 202 on which the substrate 101 is placed. A protruding portion 10 is formed at a position of the cover 201 facing the protective member 105. The protruding portion 10 protrudes from the inner wall surface of the cover 201 toward the substrate 101 and the base 202. By this protruding portion 10, the internal space of the electronic control device 100 is partitioned into a first space P1 on the side of the electronic component 104 and a second space P2 on the side of the connectors 102 and 103. A recess 13 is formed at the tip of the protruding portion 10.

[0020] FIG. 3 is a cross-sectional view showing an enlarged view of the protruding portion 10 and the protective member 105. As shown in FIG. 3, the recess 13 is recessed in a direction away from the substrate 101 and the base 202 from the tip of the protruding portion 10. The recess 13 is recessed in a substantially rectangular shape according to the shape of the protective member 105.

[0021] A protective member 105 mounted on the substrate 101 is inserted into the recess 13. A gap Q3 is present between the side 105a of the protective member 105 opposite to the mounting surface of the substrate 101 and the recess 13.

[0022] Furthermore, the tip of the protruding portion 10 has a first tip portion 11 on the first space P1 side and a second tip portion 12 on the second space P2 side. The recess 13 is formed between the first tip portion 11 and the second tip portion 12. The first tip portion 11 is positioned on the first space P1 side of the protective member 105, and the second tip portion 12 is positioned on the second space P2 side of the protective member 105. There is a gap Q1 between the first tip portion 11 and the substrate 101. Similarly, there is a gap Q2 between the second tip portion 12 and the substrate 101.

[0023] Furthermore, the first tip portion 11 and the second tip portion 12 are located on the side of the protective member 105 opposite to the mounting surface of the substrate 101, towards the substrate 101. Therefore, when viewing the internal space of the electronic control device 100 from the first space P1 to the second space P2, the first tip portion 11 and the second tip portion 12 of the protrusion 10 and the protective member 105 overlap. As a result, electromagnetic noise L1 generated from the electronic component 104 can be blocked by the protrusion 10 and the protective member 105. Consequently, electromagnetic noise L1 from the electronic component 104 can be prevented from leaking out of the housing, i.e., from the first space P1 to the second space P2. In addition, electromagnetic noise from the outside can be prevented from entering the inside of the housing, i.e., from the second space P2 to the first space P1.

[0024] In particular, with regard to low-frequency noise, as it passes through the gaps Q1, Q2, and Q3 between the protruding portion 10 and the protective member 105, it undergoes diffuse reflection as shown in Figure 3. This allows for the attenuation of electromagnetic noise.

[0025] Furthermore, with respect to high-frequency noise, the narrower the gaps Q1, Q2, and Q3 between the protrusion 10 and the protective member 105, the greater the attenuation effect as the distance the noise travels through these gaps Q1, Q2, and Q3 increases. In contrast, at two locations on both sides of the protective member 105, on the first space P1 side and the second space P2 side, the protective member 105 and the tip of the protrusion 10 overlap. Therefore, the distance that electromagnetic noise L1 travels can be increased, and an attenuation effect can be exerted even against high-frequency noise.

[0026] Furthermore, the protective member 105 is formed in a rectangular, flat plate shape, and is not intended for mounting electronic components. Therefore, not only the protective member 105, but also the shape of the protrusion 10 that covers it can be made relatively simple to manufacture. As a result, the gaps Q1, Q2, and Q3 between the protective member 105 and the protrusion 10 can be narrowed, and high-frequency noise can be further attenuated.

[0027] Furthermore, by providing gaps Q1, Q2, and Q3 between the protective member 105 and the protruding portion 10, heat generated in the first space P1 inside the housing can be released to the second space P2 through gaps Q1, Q2, and Q3. As a result, the electronic control device 100 in this example can improve not only electromagnetic noise countermeasures but also heat dissipation.

[0028] Furthermore, when the protective member 105 and the protrusion 10 are in contact, it is necessary to process the cover 201, which is the housing, with high precision. In addition, temperature changes and vibrations cause the substrate 101 and the protrusion 10 to expand and contract, repeatedly alternating between contact and non-contact states, which can cause distortion of the substrate 101. In contrast, by providing gaps Q1, Q2, and Q3 between the protective member 105 and the protrusion 10, the design of the cover 201 can be simplified, and the cover 201 can be easily assembled.

[0029] Furthermore, conductive adhesive may be filled into the gaps Q1, Q2, and Q3 between the protective member 105 and the protruding portion 10. This can improve electromagnetic noise countermeasures. In order to maintain the heat shielding effect, it is preferable to place the adhesive at intervals.

[0030] Furthermore, electromagnetic noise leakage can be prevented without the need for special electromagnetic noise countermeasures such as EMI gaskets and onboard contacts. As a result, durability can be improved and costs for EMI gaskets and onboard contacts can be reduced.

[0031] As shown in Figure 1, fixing screws for securing the cover 201 are inserted between the two protective members 105, 105. Therefore, electromagnetic noise leaking from the gap between the two protective members 105, 105 is blocked by the fixing screws and the cover 201.

[0032] 2. Second Embodiment Example Next, with reference to Figure 4, an electronic control device according to a second embodiment will be described. Figure 4 is a perspective view showing a protective member of an electronic control device according to a second embodiment.

[0033] The difference between the electronic control device according to the second embodiment and the electronic control device 100 according to the first embodiment lies in the shape of the protective member. Therefore, the protective member will be described here, and parts common to both the electronic control device 100 and the first embodiment will be denoted by the reference numeral 1, and redundant explanations will be omitted.

[0034] As shown in Figure 4, the protective member 107 is composed of multiple roughly T-shaped blocks 106. The blocks 106 are mounted so that the protrusions 106a are parallel to the mounting surface of the substrate 101. Furthermore, the orientation of the protrusions 106a of the multiple blocks 106 is such that they face in opposite directions to the protrusions 106a of adjacent blocks 106. Therefore, the multiple blocks 106 are mounted so that the orientation of their protrusions 106a is staggered.

[0035] In this way, by dividing the protective member 107 into smaller blocks 106, it can be handled as a reel product, similar to other electronic components. As a result, the blocks 106 can be mounted using a chip mounter, improving the processing efficiency. Furthermore, the heat capacity per block 106 can be reduced compared to the protective member 105 in the first embodiment. As a result, solder melts more easily, and mounting is improved.

[0036] Furthermore, as shown in Figure 4, by mounting the protrusions 106a of block 106 in an alternating orientation, multiple blocks 106 are arranged to overlap when viewed from the first space P1 to the second space P2 of the enclosure. This allows electromagnetic noise attempting to pass through the gaps between multiple blocks 106 to be diffusely reflected by the blocks 106. In addition, the length of the gap between two blocks 106, from the first space P1 to the second space P2, can be increased. As a result, electromagnetic noise passing through the gap between the two blocks 106 can be attenuated, preventing electromagnetic noise from leaking from the inside to the outside of the enclosure. Furthermore, external noise can also be prevented from entering the inside of the enclosure.

[0037] Since the other components are the same as those of the electronic control device 100 according to the first embodiment, their description will be omitted. An electronic control device having such a protective member 107 can also obtain the same effects and advantages as the electronic control device 100 according to the first embodiment described above.

[0038] 3. Third Embodiment Example Next, with reference to Figure 5, an electronic control device relating to a third embodiment will be described. Figure 5 is a perspective view showing a protective member of an electronic control device according to a third embodiment.

[0039] The difference between the electronic control device according to the third embodiment and the electronic control device 100 according to the first embodiment lies in the shape of the protective member. Therefore, the protective member will be described here, and parts common to the electronic control device 100 according to the first embodiment will be denoted by the reference numeral 1, and redundant explanations will be omitted.

[0040] As shown in Figure 5, the protective member 105A is formed in a substantially flat plate shape. Furthermore, the protective member 105A has multiple holes 115. By providing the holes 115, the overall heat capacity of the protective member 105A can be reduced. This helps to suppress problems such as difficulty in melting solder during the reflow process.

[0041] Since the other components are the same as those of the electronic control device 100 according to the first embodiment, their description will be omitted. The same effects and advantages as those of the electronic control device 100 according to the first embodiment described above can be obtained with an electronic control device having such a protective member 105A.

[0042] 4. A fourth embodiment example Next, with reference to Figure 6, an electronic control device relating to the fourth embodiment will be described. Figure 6 is a cross-sectional view showing the protruding portion and protective member of an electronic control device according to a fourth embodiment.

[0043] The electronic control device according to the third embodiment differs from the electronic control device 100 according to the first embodiment in the shape of the protruding parts and protective members. Therefore, the protective members will be described here, and parts common to the electronic control device 100 according to the first embodiment will be denoted by the reference numeral 1, and redundant explanations will be omitted.

[0044] As shown in Figure 6, a protective member 108 is mounted on the substrate 101. A protrusion 10B is formed on the cover 201B that constitutes the housing, at a position opposite to the protective member 108. The protrusion 10B protrudes from the inner wall surface of the cover 201 toward the substrate 101 and the base 202. Furthermore, in the fourth embodiment, no recess is formed at the tip of the protrusion 10B.

[0045] The protective member 108 has a U-shaped cross-section. A recess 108c is formed on one surface of the protective member 108 facing the protruding portion 10B. The recess 108c is recessed from one surface of the protective member 108 toward the substrate 101 and the base 202. The tip of the protruding portion 10B is inserted into the recess 108c.

[0046] Furthermore, a first tip portion 108a and a second tip portion 108b are formed on one surface of the protective member 108, with a recess 108c in between. The first tip portion 108a is formed on the side of the first space P1, and the second tip portion 108b is formed on the side of the second space P2.

[0047] The first tip portion 108a and the second tip portion 108b are positioned further from the substrate 101 than the tip portion of the protruding portion 10B. Therefore, when viewing the internal space of the electronic control device housing from the first space P1 side to the second space P2 (outside), the tip portion of the protruding portion 10B and the first tip portion 108a and the second tip portion 108b of the protective member 108 overlap.

[0048] Furthermore, although an example in which a recess 108c is provided in the protective member 108 has been described, the invention is not limited to this. For example, the protective member 108 may be divided into a first tip portion 108a and a second tip portion 108b.

[0049] Since the other components are the same as those of the electronic control device 100 according to the first embodiment, their description will be omitted. An electronic control device having such a protective member 108 and protrusion 10B can also obtain the same effects and advantages as the electronic control device 100 according to the first embodiment described above.

[0050] As shown in the electronic control device according to the first embodiment and the electronic control device according to the fourth embodiment, a recess is formed in one of the protruding portion and the protective member, and the other of the protruding portion and protective member is inserted into the recess.

[0051] 5. Fifth Embodiment Example Next, with reference to Figure 7, an electronic control device relating to the fifth embodiment will be described. Figure 7 is a cross-sectional view showing the protruding portion and protective member of an electronic control device according to a fifth embodiment.

[0052] The difference between the electronic control device according to the fifth embodiment and the electronic control device 100 according to the first embodiment is the dimensions of the protective member. Therefore, the protective member will be described here, and parts common to the electronic control device 100 according to the first embodiment will be denoted by the reference numeral 1, and redundant explanations will be omitted.

[0053] As shown in Figure 7, the length h in the height direction perpendicular to the mounting surface of the substrate 101 in the protective member 105C is set to be equal to the length W in the width direction parallel to the mounting surface of the substrate 101 in the protective member 105C (W=h). In other words, the protective member 105C has a square cross-sectional shape. A protrusion 10C is formed on the cover 201C. A recess corresponding to the dimensions of the protective member 105C is formed at the tip of the protrusion 10C.

[0054] Since the other components are the same as those of the electronic control device 100 according to the first embodiment, their description will be omitted. The same effects and advantages as those of the electronic control device 100 according to the first embodiment described above can be obtained with an electronic control device having such a protective member 105C and protrusion 10C.

[0055] 6. Sixth Embodiment Example Next, with reference to Figure 8, an electronic control device according to the sixth embodiment will be described. FIG. 8 is a cross-sectional view showing a protruding portion and a protective member of an electronic control device according to a sixth embodiment example.

[0056] The difference between the electronic control device according to the sixth embodiment example and the electronic control device 100 according to the first embodiment example lies in the dimensions of the protective member. Therefore, here, the protective member will be described, and parts common to the electronic control device 100 according to the first embodiment example will be denoted by the same reference numerals, and duplicate descriptions will be omitted.

[0057] As shown in FIG. 7, the length h in the height direction perpendicular to the mounting surface of the substrate 101 in the protective member 105D is set to be longer than the length W in the width direction parallel to the mounting surface of the substrate 101 in the protective member 105D (W < h). That is, the protective member 105D is formed in a vertically long cross-sectional shape. A protruding portion 10D is formed on the cover 201D. And a recess corresponding to the dimensions of the protective member 105D is formed at the tip of the protruding portion 10D.

[0058] Since other configurations are the same as those of the electronic control device 100 according to the first embodiment, descriptions thereof will be omitted. An electronic control device having such a protective member 105D and a protruding portion 10D can also obtain the same operational effects as the electronic control device 100 according to the first embodiment example described above.

[0059] Note that a member having a horizontally long cross-sectional shape, like the protective member 105 according to the first embodiment example, can be arranged more perpendicularly to the substrate 101 than the vertically long member shown in the protective member 105D according to the sixth embodiment example. Furthermore, the horizontally long protective member 105 shown in the first embodiment example can improve vibration resistance more than the vertically long protective member 105D shown in the sixth embodiment example.

[0060] It should be noted that the invention is not limited to the embodiments described above and shown in the drawings, and various modifications are possible without departing from the gist of the invention as described in the claims. Furthermore, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. In addition, it is possible to add, delete, or replace parts of the configuration of other embodiments.

[0061] In this specification, although terms such as "parallel" and "orthogonal" are used, these do not mean only strictly "parallel" and "orthogonal," but may also refer to states that are "approximately parallel" or "approximately orthogonal," which include "parallel" and "orthogonal" and are within a range in which they can perform their functions. [Explanation of symbols]

[0062] 10, 10B, 10C, 10D...Protruding part, 11...First tip, 12...Second tip, 13...Recess, 100...Electronic control unit, 101...Substrate, 101a...Fixing hole, 102, 103...Connector, 104...Electronic component, 105, 105A, 105C, 105D, 107, 108...Protective member, 105a...One side, 106...Block, 106a...Convex part, 107...Protective member, 108a...First tip, 108b...Second tip, 108c...Recess, 115...Hole, 201, 201B, 201C, 201D...Cover (housing), 202...Base (housing), L1...Electromagnetic noise, P1...First space, P2...Second space, Q1, Q2, Q3... gaps

Claims

1. A circuit board on which electronic components and connectors are mounted, A protective member mounted between the electronic component and the connector on the aforementioned substrate, A housing comprising a base on which the substrate is placed and a cover that covers the base on which the substrate is placed, The cover is provided with a projection that is located opposite to the protective member and protrudes toward the substrate and the base, A recess is formed in one of the protruding portion and the protective member. The other of the protruding portion and the protective member is inserted into the recess. When viewed from the inside of the housing outwards, the protruding portion and the protective member are arranged to overlap. There is a gap between the protruding portion and the protective member. Electronic control unit.

2. A recess is formed at the tip of the protruding portion. The protective member is inserted into the recess of the protruding portion. The electronic control device according to claim 1.

3. The protective member is formed by dividing it into multiple blocks. The electronic control device according to claim 1.

4. The block is formed in a T-shape, with its protrusions arranged parallel to the mounting surface of the substrate. Multiple of the aforementioned blocks are arranged with the orientation of the protrusions alternating. When viewed from the inside of the enclosure towards the outside, the multiple blocks are arranged to overlap each other. The electronic control device according to claim 3.

5. Multiple holes are formed in the protective member. The electronic control device according to claim 1.

6. A recess is formed on one surface of the protective member facing the protruding portion. The front end of the protruding portion is inserted into the recess of the protective member. The electronic control device according to claim 1.

7. The protective member is formed of a conductive material or a material capable of absorbing electromagnetic waves. The electronic control device according to claim 1.

8. The length of the protective member in the height direction perpendicular to the mounting surface of the substrate is set to be shorter than the length of the protective member in the width direction parallel to the mounting surface of the substrate. The electronic control device according to claim 1.

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