JP2013233914A - Electronic control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic control unit in which a connector is exposed from a case, capable of achieving both of preventing interference of the case with the connector upon thermal deformation and preventing contamination from a gap between the case and the connector, in the electronic control unit.SOLUTION: A case 2 of an electronic control unit 1 includes a body 3 whose one surface is opened as a housing mouth of a printed board and a lid 4 which closes the housing mouth. An opening 42 into which a connector 5 is fitted is formed on the lid 4. Right and left gap covers 44 with which right and left directional gaps between the opening 42 and the connector 5 are covered from a front side are disposed on right and left edges of the opening 42. The right and left directional gaps are set to such a gap width that the connector 5 and the case 2 do not interfere with each other upon thermal deformation. A board edge surface in a depth direction of the printed board housed in the case 2 is brought into contact with an inner surface of the case 2. A depth directional gap between the right and left gap cover 44 and the connector 5 is set to a gap width satisfying IP 40.

Description

  The present invention relates to an electronic control unit in which a connector is exposed from a case that accommodates a substrate.

  Various electronic controls are incorporated in automobiles in order to improve safety, fuel saving, comfort, convenience, and the like, and many ECUs (electronic control units) for implementing these electronic controls are installed. The ECU generally includes a circuit and a case (see, for example, Patent Document 1). Circuits consist of microcomputers that realize electronic control, oscillation circuits that are indispensable to microcomputers, power supply circuits, and various input / output circuits that are necessary for control (circuits, various ICs, resistors, capacitors, etc.) on the printed circuit board. To be implemented. The printed circuit board is mounted with various connectors, such as various sensors, actuators, and other ECUs (connector housings) for realizing power supply and electronic control from the battery to the ECU. A connection port into which an external (vehicle side) connector plug is inserted is provided on the front surface of the connector. The circuit (substrate) is generally stored in a case molded from resin or metal for the purpose of preventing external stress on the circuit element and malfunction due to electrical contact with the outside. An opening is formed in the case, and the board is accommodated in the case so that the front surface of the connector fits into the opening of the case.

JP 2010-118492 A

  By the way, the number of harnesses to which one ECU is connected to the other has increased due to complication of electronic control, systemization, integration of ECUs, and the like, and multipolarization of connectors of each ECU is progressing. On the other hand, if the connectors to be multipolarized are combined into one, a greater force is required for insertion / extraction, so it is realized by dividing into multiple blocks or multiple low-polarity connectors to ensure the workability of factory workers. It tends to be.

  In addition, for ECUs that control important functions such as vehicle theft, a test standard for preventing foreign matter from entering the ECU case, such as IP40, has been established, and it is necessary to design the clearance between the case and the connector so that there is no gap of 1 mm or more. There is also an ECU.

  Conventionally, the connector is composed of a single housing and meets the IP40 test standard, so the connector has been divided into an ECU that has been designed so that the clearance around the connector is less than 1 mm. Therefore, there is a problem that the connector and the case easily interfere with each other due to a difference in expansion coefficient between the printed circuit board (mainly glass fiber) and the case (for example, a resin case) due to a change in ambient temperature around which the ECU is mounted. This problem will be described with reference to the drawings. Here, FIG. 14A is a perspective view of the ECU 900 when viewed from the opening 912 side of the case 910. 14B to 14E are cross-sectional views of the ECUs 900 and 901 in the opening 912. Specifically, FIGS. 14B and 14C are cross-sectional views of the ECU 900 when the number of the connector housing is one, FIG. 14B is a state at room temperature (at room temperature), and FIG. Indicates a state at a low temperature. 14D and 14E are cross-sectional views of the ECU 901 when there are a plurality of connector housings (three in the figure). FIG. 14D is a state at normal temperature, and FIG. ) Shows the state at low temperature. 15A and 15B are cross-sectional views of the ECU 901 from the upper surface of the case 910. FIG. 15A shows a state at normal temperature, and FIG. 15B shows a state at low temperature. Yes.

  As shown in FIGS. 14A to 14C, one conventional connector 920 (even if the connector connection port 922 is a plurality of blocks is a single connector) has a case 910 around it. It is assumed that the gap 941 is secured by 0.5 mm at the normal temperature in FIG. When the ECU 900 designed in this way is left in a low temperature environment (a temperature below room temperature, for example, 0 ° C.), the printed circuit board 930 is relatively 0 due to the difference in thermal expansion coefficient between the printed circuit board 930 and the case 910. The positional relationship spreads by about 2 to 0.4 mm (see FIG. 14C). At this time, since the connector 920 (connector housing) is not necessarily the same as the case 910 but is the same resin, the gap 941 between the connector 920 and the case 910 is not limited even if the printed circuit board 930 is expanded. There is no significant difference from the room temperature (room temperature) state, and approximately 0.5 mm is maintained (see FIG. 14C).

  On the other hand, consider an ECU 901 on which three connectors 950 are mounted as shown in FIGS. 14D, 14E, and 15, for example. Also in this case, it is assumed that the gap 942 between the connector 950 and the case 910 is secured by 0.5 mm at room temperature (see FIGS. 14D and 15A). When the ECU 901 designed in this way is left in a low temperature environment, as shown in FIGS. 14E and 15B, the printed circuit board 930 is relatively about 0.2 to 0.4 mm in the case 910. Spread against. Accordingly, the left and right connectors 950 with respect to the center of the case 910 have a positional relationship that is relatively 0.1 to 0.2 mm away from the center. In this case, the gap 942 between the case 910 and the connector 950 (particularly, the gap between the broken line portion B in FIG. 15) is reduced by 0.1 to 0.2 mm, depending on the case 910, circuit size variations, and assembly variations. Case 910 interferes. In the surface mount type connector, when it interferes with the case, stress is applied to the housing of the connector, and the stress is transmitted to the soldering portion, so that the solder life is shortened. Therefore, it is not preferable that the connector and the case interfere with each other.

  On the other hand, when the ECU 901 is placed in a high temperature environment such as 80 ° C., the case 910 becomes relatively large with respect to the printed circuit board 930, and the gap 942 is widened.

  As described above, since the ECU case, the connector, and the board are thermally deformed, it is necessary to set a gap width between the case and the connector in consideration of the heat deformation. However, taking into account thermal deformation at low temperatures and securing a gap (large gap) that does not interfere with the case and the connector in advance, the IP40 test standard described above cannot be satisfied at high temperatures, and foreign matter contamination deteriorates. There is. On the contrary, if the gap (small gap) that satisfies the IP40 test standard is set in consideration of thermal deformation at high temperature, the case and the connector may interfere with each other at low temperature.

  The present invention has been made in view of the above circumstances, and can achieve both prevention of interference between the case and the connector at the time of thermal deformation and good maintenance of foreign matter mixing from the gap between the case and the connector. It is an object to provide a control unit.

In order to solve the above problems, an electronic control unit of the present invention includes a case in which an opening is formed,
A connector having a connection port connected to the outside on the front surface is mounted on the end, and the board accommodated in the case so that the front surface of the connector fits in the opening;
Depth direction that is provided so as to cover the left and right gaps that are left and right gaps of the opening and the connector from the front side from the front side, and protrudes from the left and right ends of the opening to the front side. A left and right gap cover portion set to a gap width through which a foreign object having a certain size or more does not pass,
The substrate is accommodated in the case so that the plate end surface in the depth direction of the substrate contacts the inner surface of the case,
The left-right gap is set to a gap width at which the connector and the case do not interfere even when the relative position of the connector and the case changes due to thermal deformation.

  According to the present invention, since the gap between the opening of the case and the connector in the left-right direction is set to a gap width at which the connector and the case do not interfere even if the relative position of the connector and the case changes due to thermal deformation, Interference between the case and the connector can be prevented. Since the left-right gap is covered with the left-right gap cover portion from the front side, it is possible to prevent foreign matter from entering the case from the left-right gap. In addition, since the board end surface in the depth direction of the substrate is in contact with the inner surface of the case, it is possible to suppress the relative position of the substrate (connector) and the case in the depth direction from changing even if there is a temperature change. As a result, even if there is a temperature change, it is possible to suppress a change in the depth direction gap that is the gap between the front surface of the connector and the left and right gap cover portions. Further, the depth direction gap is set to a gap width (for example, a gap width satisfying IP40) through which a foreign object having a certain size or more does not pass. Therefore, even if there is a temperature change, it is possible to prevent interference between the case (left and right gap cover portion) and the connector in the depth direction gap, and to prevent foreign matter from entering the case from the depth direction gap. As described above, according to the present invention, it is possible to achieve both the prevention of the interference between the case and the connector and the good maintenance of the foreign matter mixing property from the gap between the case and the connector.

It is a perspective view of ECU1. It is a front view of ECU1. It is a figure when the cover part 4 is removed from ECU1 of FIG. It is sectional drawing from the upper surface of ECU1, and is the figure which showed the state at the time of normal temperature (the figure (A)), and the state at the time of a thermal deformation (the figure (B)). It is an enlarged view of the A section of FIG. FIG. 6 is a front view from the back side of the lid part 4. FIG. 4 is a perspective view from the back side of the lid part 4. It is an enlarged view of the clamping part 45. FIG. It is a schematic diagram when the structure around the clamping part 45 is seen from the side. It is a schematic diagram of the structure around the connectors 51-53 when viewed from the same direction as FIG. It is the figure which showed typically the contact part of the lid body 41 and the printed circuit board 6. FIG. It is sectional drawing from the upper surface of ECU which concerns on a modification. It is sectional drawing from the side of ECU which concerns on another modification. It is a figure from the connector opening side of conventional ECU. It is sectional drawing from the upper surface of conventional ECU, and is the figure which showed the state at the normal temperature (the figure (A)) and the state at the time of a thermal deformation (the figure (B)).

  Hereinafter, an embodiment of an electronic control unit according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a vehicle ECU 1 (Electronic Control Unit) as an electronic control unit of the present embodiment. FIG. 2 is a view (front view) when the ECU 1 is viewed from the exposed side of the connector 5. FIG. 3 is a view when a lid 4 described later is removed from the ECU 1 of FIG. In the following, the left and right direction of the paper surface in FIGS. 2 and 3 is the left and right direction of the ECU 1, the vertical direction of the paper surface is the vertical direction of the ECU 1, and the vertical direction of the paper is the front and rear direction (depth direction) of the ECU 1.

  The ECU 1 is, for example, an engine ECU that controls the engine or a door ECU that controls a door lock. As shown in FIG. 1, the ECU 1 includes a substantially rectangular parallelepiped case 2 that is longer on the left and right than on the upper and lower sides. The case 2 is formed of a resin such as ABS resin. The case 2 may be made of a metal such as aluminum. The case 2 has a substantially rectangular parallelepiped (cylindrical shape with the back side closed) main body 3 opened as an accommodation port 31 (see FIG. 3) of the substrate 6, which will be described later, and a left and right elongated shape that closes the accommodation port 31. The lid part 4 is provided. The accommodation port 31 is formed on one of the four surfaces excluding the upper surface and the lower surface of the main body 3. Hereinafter, the accommodation port 31 side is referred to as a front side or a front side of the ECU 1.

  The lid 4 is fixed on the left side 32 and the right side 33 of the main body 3. Specifically, on the front side of the left and right side surfaces 32, 33 of the main body portion 3, a protruding portion 34 that protrudes laterally from the side surfaces 32, 33 is formed integrally with the main body portion 3. Further, at the left and right end portions of the lid portion 4, an attachment portion 43 that protrudes rearward (backward) from each end portion is formed integrally with the lid portion 4. Hereinafter, the part excluding the attachment part 43 of the lid part 4 is referred to as a lid body 41. FIG. 7 is a perspective view from the back side of the lid 4. As shown in FIG. 7, the attachment portion 43 is annular. The lid portion 4 is attached to the main body portion 3 so that the protruding portion 34 fits into the open portion of the attachment portion 43. In other words, the lid 4 is attached to the main body 3 by claw fitting.

  A space 30 (see FIG. 4A) is formed inside the main body 3 from the accommodation port 31 to the rear end of the main body 3. The space 30 has a substantially rectangular parallelepiped shape in accordance with the shape of the main body 3. In the space 30, circuit elements (various ICs, resistors, capacitors, etc.) constituting a microcomputer for realizing electronic control, an oscillation circuit indispensable for the microcomputer, a power supply circuit, and various input / output circuits necessary for control are mounted A printed circuit board 6 is accommodated. The printed circuit board 6 is a glass epoxy board in which, for example, a glass fiber cloth is overlapped with an epoxy resin. The printed board 6 is not limited to a glass epoxy board, and may be a board having any composition such as an alumina board.

  4A and 4B are cross-sectional views from the upper surface of the ECU 1. FIG. 4A shows a state at room temperature (room temperature), and FIG. 4B shows a state at the time of thermal deformation. As shown in FIG. 4A, the printed circuit board 6 has a rectangular shape in plan view. On the upper surface 601 of the printed circuit board 6, in addition to the above-described microcomputer and the like, surface mounting for connecting to the outside of various sensors, actuators, other ECUs, etc. in order to realize power supply from the battery to the ECU 1 and electronic control. A type connector 5 is mounted. The connector 5 has a substantially rectangular parallelepiped shape. The connector 5 is mounted on the front end of the printed circuit board 6 such that a part of the front side of the connector 5 protrudes from the front end of the printed circuit board 6. In the present embodiment, a plurality of connectors 51 to 53 as the connectors 5 are arranged on the front end of the printed circuit board 6 so as to be arranged on the left and right. As shown in FIG. 3, a connection port 54 to which an external connector plug is connected is formed on the front surface of the connector 5 (each connector 51, 52, 53). The connection port 54 is a hollow portion having a rectangular shape in a front view and a constant width in the depth direction. Hereinafter, the connector 5 may be referred to as a connector housing in order to distinguish it from an external connector plug. The connector housing 5 is made of a resin such as ABS resin.

  As shown in FIGS. 1 and 2, the front surfaces (connecting ports 54) of the connectors 51, 52, 53 are exposed from the case 2 (lid portion 4). Specifically, the lid 4 (lid body 41) has three openings 421, 422, and 423 formed on the left and right. In the following description, reference numeral “42” is used when the openings 421, 422, and 423 are not distinguished. FIG. 6 is a front view from the back side of the lid 4. As shown in FIG. 6, the openings 421, 422, and 423 are formed in a rectangular shape in front view according to the front shape of the connector 5. The sizes of the openings 421, 422, and 423 are slightly larger than the size of the front surface of the connector 5. As shown in FIG. 4A, the front surface of the connector 51 arranged on the left side is fitted in the left opening 421, and the connector 52 arranged in the middle is fitted in the middle opening 422 and arranged on the right side. The connector 53 thus fitted fits into the opening 423 on the right side. Each connector 51-53 is arrange | positioned in the form which has a clearance gap between each opening 421-423 so that it may not interfere with each opening 421-423.

  The left-right gap 71 (left-right gap) between the connector 5 and the opening 42 is a case where the relative position among the printed circuit board 6, the connector 5, and the case 2 changes due to thermal deformation. The gap width is set so as not to interfere. For example, when the thermal expansion coefficient of the case 2 (the main body 3 and the lid 4) is larger than that of the printed circuit board 6, the shrinkage of the case 2 is smaller than the contraction of the printed circuit board 6 at a low temperature (for example, 0 ° C.). growing. As a result, the case 2 contracts in the left-right direction relative to the printed circuit board 6. In other words, when the size of the case 2 is used as a reference, the printed circuit board 6 spreads in the left-right direction relative to the case 2 as shown in FIG. As the printed circuit board 6 expands (in other words, as the case 2 contracts), the arrangement position of the connector 5 with respect to the opening 42 varies. In particular, when the plurality of connectors 51 to 53 are arranged on the left and right as in this embodiment, the left connector 51 and the right connector 53 are likely to fluctuate. In the case of FIG. 4B, the left connector 51 varies to the left than in FIG. 4A, and the right connector 53 varies to the right than in FIG. 4A. Yes. As a result, the left-right clearance 71 (particularly the left-right clearance 711 with the left connector 51 and the left-right clearance 716 with the right connector 53) is smaller than that at room temperature in FIG. Even in this case, the connectors 51, 52, 53 and the openings 421, 422, 423 do not interfere with each other.

  That is, the gap width of the left-right gap 71 at room temperature in FIG. 4A is set wider than the conventional left-right gap 942 in FIG. 15A, specifically, for example, 1 mm to 2 mm. The value is between. In FIG. 15A, the conventional gap 942 in the left-right direction is set to 1 mm or less (for example, 0.5 mm) in order to satisfy the IP40 test standard (a 1 mm rod (foreign matter cannot pass)). As described above, the gap 71 in the left-right direction of the present embodiment is set to be wider than that in the prior art, so there is a possibility that the IP40 may not be satisfied as it is, but a countermeasure is taken to satisfy the IP40.

  Specifically, a left and right gap cover portion 44 that covers the left and right gap 71 from the front side is formed integrally with the lid portion 4 at the left and right ends of the opening 42. The left and right gap cover portion 44 is provided around the left end of the left connector 51 and covers the left and right gap 711 on the left side of the connector 51, and is provided between the left connector 51 and the middle connector 52. And a cover portion 442 that covers both the right and left gap 712 on the right side and the left and right gap 713 on the left side of the connector 52. Further, the left / right gap cover portion 44 is provided between the middle connector 52 and the right connector 53 and covers a right / left gap 714 on the right side of the connector 52 and a left / right gap 715 on the left side of the connector 53. And a cover portion 444 provided around the right end of the right connector 53 and covering the right and left gap 716 on the right side of the connector 53.

  As shown in FIG. 4A, the left and right gap cover portions 441 to 444 are arranged at positions on the front side of the front surface 57 of the connector 5, that is, with a gap between the front surface 57 and the front surface 57. Specifically, as shown in FIGS. 2 and 4A, each of the left and right gap cover portions 441 to 444 is one of the left and right ends 55 of the front surface 57 of the connector 5 (see FIG. 3, other than the connection port 54). It is provided so as to overlap only the portion and not to overlap the remaining portion including the connection port 54. That is, when the ECU 1 is viewed from the front direction of FIG. 2, a part of the left and right ends 55 of the connector 5 is hidden by the left and right gap cover part 44 and the remaining part is visible. Further, since the connection port 54 is not hidden, the connection with an external connector plug is not hindered. The overlapping range of the left and right gap cover portions 44 and the left and right ends 55 (the overlapping range at normal temperature) is such that the horizontal gap 71 is exposed to the outside even when the relative position between the case 2 and the connector 5 changes during thermal deformation. And the left and right gap cover 44 is set so as not to overlap the connection port 54. The overlapping range is set to, for example, half the length of the left and right ends 55 in the left-right direction.

  FIG. 5 is an enlarged view of a broken line portion A in FIG. As shown in FIG. 5, the gap 73 (depth direction gap) between the front surface 57 of the connector 5 and the left and right gap cover portion 44 is set to a gap width satisfying IP40 at room temperature, that is, 1 mm or less (eg, 0.65 mm). Has been. And in this invention, the countermeasure which suppresses the fluctuation | variation of the depth direction clearance 73 is taken even at the time of thermal deformation. Specifically, as shown in FIG. 4A, the printed circuit board 6 is accommodated in the case 2 such that the front and rear (in the depth direction) plate end surfaces 61 and 62 are in contact with the inner surface of the case. Specifically, the plate end surface 61 on the back side of the printed circuit board 6 is in contact with the rear surface 35 on the inner surface of the main body 3. Further, the front plate end surface 62 of the printed circuit board 6 is in contact with the back surface 46 (see FIGS. 6 and 7) of the lid portion 4. For this reason, for example, even if the case 2 is thermally shrunk and tries to shrink in the depth direction (front-rear direction), the shrinkage is suppressed by contact with the printed circuit board 6. Even if the printed circuit board 6 expands in the depth direction due to thermal expansion, the contact with the case 2 can suppress the expansion. Therefore, the depth direction gap 73 can be kept almost constant regardless of thermal deformation, and IP40 can be satisfied. In addition, the longitudinal interference between the case 2 and the connector 5 can be prevented.

  As shown in FIGS. 6 and 7, the back surface 46 of the lid body 41 is integrally formed with the lid body 41 so as to support the end portion of the printed circuit board 6 so as to be sandwiched from above and below. A plurality of sandwiching portions 45 are formed in the left-right direction of the lid body 41. In the present embodiment, four holding portions 451 to 454 are formed around the lower sides of the left and right ends of the openings 421 to 423. In addition, on the rear surface 35 of the main body 3 (see FIG. 4A), a clamping portion (not shown) is formed in the same shape and the same height as the clamping portion 45 in FIGS. The printed circuit board 6 is supported by these clamping parts 45. At this time, the height position of the sandwiching portion 45 is set so that the front plate end surface 62 (see FIG. 4A) of the printed circuit board 6 is positioned directly below the opening 42 on the back surface 46 of the lid body 41. ing. In this embodiment, the clamping part is not formed in the left inner surface 65 and the right inner surface 66 (refer FIG. 4 (A)) of case 2 (main-body part 3). Instead of the sandwiching portions 45 of the front and rear inner surfaces 36, 46 of the case 2, sandwiching portions may be formed on the left and right inner surfaces 65, 66.

  FIG. 8 is an enlarged view of the clamping part 45 of FIG. As shown in FIG. 8, the sandwiching portion 45 includes an upper portion 455 disposed on the upper surface 601 (mounting surface of the electronic component such as the connector 5, see FIG. 3) side of the printed circuit board 6 and the lower surface 602 side of the printed circuit board 6. And a lower side portion 456 disposed at the bottom. A portion 455a of the upper portion 455 that contacts the upper surface 601 of the printed circuit board 6 is planar. On the other hand, a portion 456a of the lower side portion 456 that contacts the lower surface 602 of the printed circuit board 6 has a shape that allows crushing deformation, specifically a pointed shape. FIG. 9 is a schematic view of the structure around the clamping part 45 when viewed from the side. By making the shape of the clamping part 45 as shown in FIG. 8, as shown in FIG. 9, the printed circuit board 6 is assembled in the case 2 with reference to the upper surface 601 of the printed circuit board 6 in contact with the planar upper part 455. be able to. As a result, even if the printed circuit board 6 is thermally expanded and is in a state indicated by reference numeral “63” in FIG. 9, the position of the upper surface 601 serving as the reference surface can be fixed. In this case, the lower portion 456 is pushed downward by the thermally expanded printed circuit board 63, and as a result, it is crushed and deformed. Therefore, the relative positional relationship in the vertical direction between the connector 5 mounted on the upper surface 601 and the opening 42 formed on the upper surface 601 side can be made substantially constant regardless of thermal deformation. That is, the gap 721 between the lower surface 581 of the connector 5 and the lower end 424 of the opening 42 and the gap 722 between the upper surface 582 of the connector 5 and the upper end 425 of the opening 42 can be made substantially constant regardless of thermal deformation. Therefore, IP40 can be satisfied for the upper and lower gaps 721 and 722 as well. Moreover, the interference in the up-down direction between the connector 5 and the opening 42 can also be prevented.

  FIG. 10 is a schematic diagram of the structure around the connectors 51 to 53 when viewed from the same direction as FIG. In FIG. 10, the connectors 51 to 53 are shown through. As shown in FIGS. 6, 7, and 10, a protrusion 47 is formed integrally with the lid body 41 on the back surface 46 of the lid body 41. In the present embodiment, the protrusion 47 is formed near the center of the lid body 41 in the left-right direction. Further, a concave portion 64 is formed in the front end face 62 of the printed board 6 (see FIG. 10). The printed circuit board 6 is assembled in the case 2 such that the recess 64 fits into the protrusion 47. At this time, the formation positions of the protrusions 47 and the recesses 64 are set so that the horizontal gaps 711 to 716 between the connectors 51 to 53 and the openings 421 to 423 are uniform. Thereby, when the printed circuit board 6 is assembled, the printed circuit board 6 can be prevented from shifting to the left and right, and the printed circuit board 6 can be assembled (accommodated) at a predetermined position in the case 2 with high accuracy. If the left and right gaps 711 to 716 can be made uniform, the protrusion 47 may not be formed near the center of the lid body 41 in the left and right direction, even if it is formed at a position near the right side or the left side, for example. good.

  FIG. 11 is a diagram schematically showing a contact portion between the lid main body 41 and the printed circuit board 6. As shown in FIG. 11, the portions 461 and 462 of the back surface 46 that face the portion 621 from the left and right ends of the plate end surface 62 of the printed circuit board 6 are the other portions 463 (parts from the left and right ends of the printed circuit board 6. It is recessed more than the part 46 of the back surface 46 which faces the part 622 except 621. In other words, the portion 463 of the back surface 46 that is in contact with the portion 622 excluding the portion 621 from the left and right ends of the plate end surface 62 is convex with respect to the other portions. That is, the projection 463 prevents a part 621 of the plate end surface 62 from contacting the back surface 46. As a result, the portion 411 of the lid main body 41 (the portion not in contact with the plate end surface 62) from the attachment portion 43 to the plate end surface 62 can be lengthened. That is, the length d1 of the portion 411 is larger than the length d2 when the entire plate end surface 62 is in contact. Therefore, when the printed circuit board 6 is thermally deformed (stretched) in the front-rear direction (depth direction), the deflection of the portion 411 can be increased. As a result, the stress applied to the mounting portion 43 and the protruding portion 34 can be reduced, and cracks and the like around the mounting portion 43 and the protruding portion 34 can be prevented.

  FIG. 11 shows an outline 56 when the three connectors 51 to 53 are considered as one connector. In the present embodiment, the range of the convex portion 463 is equal to the left-right width of the connector outline 56 (the vertical width in the paper surface direction of FIG. 11). That is, the portion 622 of the plate end surface 62 corresponding to the portion where the connectors 51 to 53 are mounted is in contact with the back surface 46, and the other portion 621 of the plate end surface 62 is not in contact with the back surface 46. As described above, the depth-direction gap 73 (see also FIG. 5) can be kept substantially constant regardless of thermal deformation by the contact between the portion 622 of the plate end surface 62 and the back surface 46.

  The electronic control unit (ECU) according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the claims. FIG. 12 is a cross-sectional view from the upper surface of an ECU according to a modification. In FIG. 12, the same or similar components as those in the above embodiment are given the same reference numerals. As shown in FIG. 12, the left and right gap cover 44 that covers the opening 42 and the left and right gap 71 of the connector 5 may be formed integrally with the main body 3 of the case. The shape and position of the left and right gap cover portion 44 are the same as those of the left and right gap cover portion 44 in FIG. In this case, an accommodation port 31 for accommodating the printed circuit board 6 is formed on the back side of the main body 3, and a lid portion 4 for closing the accommodation port 31 is provided.

  FIG. 13 is a cross-sectional view from the side of an ECU according to another modification. In FIG. 13, the same reference numerals are given to the same or similar components as those in the above embodiment. As shown in FIG. 13, a case 2 in which the lower case 21 and the upper case 22 are combined may be employed. In this case, the opening 42 of the connector 5 is configured by a combination of the front portion 211 of the lower case 21 and the front portion 221 of the upper case 22. The left and right gap cover portion 44 that covers the left and right gap between the connector 5 and the opening 42 is formed, for example, in the front portion 221 of the upper case 22.

1 ECU (electronic control unit)
2 Case 3 Body 4 Lid 42 Opening 44 Left and right gap cover 5 Connector 6 Printed circuit board 71 Left and right gap 73 Depth gap

Claims (5)

A case in which an opening is formed;
A connector having a connection port connected to the outside on the front surface is mounted on the end, and the board accommodated in the case so that the front surface of the connector fits in the opening;
Depth direction that is provided so as to cover the left and right gaps that are left and right gaps of the opening and the connector from the front side from the front side, and protrudes from the left and right ends of the opening to the front side. A left and right gap cover portion set to a gap width through which a foreign object having a certain size or more does not pass,
The substrate is accommodated in the case so that the plate end surface in the depth direction of the substrate contacts the inner surface of the case,
The electronic control unit according to claim 1, wherein the gap in the left-right direction is set to a gap width at which the connector and the case do not interfere even if the relative position of the connector and the case changes due to thermal deformation. In the case, a plurality of the openings are formed side by side,
The electronic control unit according to claim 1, wherein a plurality of the connectors arranged in each of the openings are mounted on the substrate. A protrusion is formed on the inner surface of the case that contacts the plate end surface in the depth direction of the substrate,
The plate end surface of the substrate is formed with a recess into which the protrusion is fitted,
The housing position in the left-right direction of the board with respect to the case is positioned by fitting the protrusion and the recess so as to be set in the left-right gap where the connector and the case do not interfere with each other. The electronic control unit according to claim 1 or 2. The inner surface of the case is provided with a sandwiching portion that supports the substrate so as to sandwich the end of the substrate from above and below,
The portion of the clamping portion that contacts the upper surface of the substrate on which the connector is mounted is planar.
4. The electronic control unit according to claim 1, wherein a portion of the sandwiching portion that contacts the lower surface of the substrate has a shape that allows crushing deformation. 5. The case includes a rectangular parallelepiped main body having one surface opened as an accommodation port for the substrate, and a lid for closing the accommodation port,
The lid portion includes a lid main body disposed in the receiving port, and an attachment portion that is provided so as to wrap around the side surface of the main body portion from the left and right ends of the lid main body,
The substrate is accommodated in the case such that the plate end surface of the substrate contacts the inner surface of the lid body,
The inner surface of the lid main body facing a part from the left and right ends of the plate end surface of the substrate is recessed from the other part so as not to contact the part. The electronic control unit according to claim 1.

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