Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
  • B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/30—Assembling printed circuits with electric components, e.g. with resistors
  • H05K3/32—Assembling printed circuits with electric components, e.g. with resistors electrically connecting electric components or wires to printed circuits
  • H05K3/34—Assembling printed circuits with electric components, e.g. with resistors electrically connecting electric components or wires to printed circuits by soldering
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K5/00—Casings, cabinets or drawers for electric apparatus

Definitions

• the present invention relates to an electronic device and a method for manufacturing an electronic device.
• the circuit board and the electronic components mounted on the board are housed in a case to ensure robustness and EMC measures (for example, Patent Publication No. 5528641).
• Some electronic devices as described above are manufactured by placing electronic components inside a case, and then placing a board on top of the electronic components.
• the electronic components are fixed in the case in advance with screws, so that they are positioned with the board that will be housed later.
• manufacturing costs increase due to the need to process screw holes for positioning and increase the number of screws.
• the present invention has been made to solve the above problems, and aims to provide an electronic device and a method for manufacturing an electronic device that facilitates the positioning of the board and electronic components housed in the case, while also reducing manufacturing costs.
• the electronic device comprises a substrate, an electronic component mounted on the substrate, and a case that houses the substrate and the electronic component, and the case has a positioning portion on a surface facing the mounting surface of the substrate on which the electronic component is mounted, which is capable of positioning and arranging the electronic component before the electronic component is mounted on the substrate.
• the method for manufacturing an electronic device is a method for manufacturing an electronic device comprising a substrate, an electronic component mounted on the substrate, and a case for accommodating the substrate and the electronic component, the case having a positioning portion on a surface facing the mounting surface of the substrate on which the electronic component is mounted, capable of positioning and arranging the electronic component before the electronic component is mounted on the substrate, the method comprising the steps of arranging the electronic component in the case while positioned by the positioning portion, and arranging the substrate from above the electronic component positioned and arranged in the case.
• the case has a positioning portion on the surface facing the mounting surface of the board on which the electronic component is mounted.
• This positioning portion can position and arrange the electronic component before it is mounted on the board. Therefore, the electronic component can be positioned with respect to the board to be accommodated later without having to be fixed in place by screws inside the case, which makes it easier to position the board and electronic component and reduces manufacturing costs.
• the electronic components are positioned in the case by the positioning parts, and then the board is placed on top of the electronic components. This makes it possible to position the electronic components with the board that will be housed later without having to screw them into the case, which makes it easier to position the board and electronic components and reduces manufacturing costs.
• FIG. 1 is an exploded perspective view showing an electronic device according to an embodiment of the present invention.
• FIG. 2 is a plan view of the case according to the embodiment, seen from above.
• 4 is an enlarged plan view showing a state in which the electronic component according to the embodiment is placed on a positioning part.
• FIG. 4C is a schematic diagram for explaining the manufacturing process of an electronic device, in which (A) shows the process of arranging an electronic component in a positioning portion, (B) shows the process of stacking the board from above the electronic component, (C) shows the process of flipping the case upside down and mounting the electronic component on the board by flow soldering, and (D) shows the process of flipping the case upside down again after the process of FIG. 4C to return it to its original position.
• 1 is a cross-sectional side view of an electronic device according to an embodiment of the present invention, showing a state after an electronic component has been mounted on a substrate.
• 1 shows a first modified example of a positioning portion according to this embodiment, in which (A) is a plan view showing an electronic component placed in the positioning portion before being mounted on a substrate, and (B) is a side cross-sectional view showing the electronic component after being mounted on the substrate.
• a second modified example of the positioning portion according to this embodiment is shown, in which (A) is a plan view showing the state in which an electronic component is placed in the positioning portion before being mounted on a substrate, and (B) is a side cross-sectional view showing the state after the electronic component has been mounted on the substrate.
• the electronic device 1 constitutes, for example, an ECU (Electronic Control Unit) mounted on a vehicle (not shown).
• the electronic device 1 controls the operation of the on-board equipment based on information from various sensor devices mounted on the vehicle.
• the electronic device 1 comprises a substrate 2, a number of electronic components mounted on the substrate 2, and a case 12 that houses the substrate 2 and the number of electronic components.
• FIG. 1 illustrates a semiconductor element 3 and two connectors 15, 17 as an example of the number of electronic components.
• the semiconductor element 3 corresponds to an example of an "electronic component" as described in the claims.
• the substrate 2 has mounting surfaces on both the top and bottom, and a wiring pattern (not shown) made of, for example, copper foil is formed on each mounting surface.
• the wiring pattern electrically connects multiple electronic components mounted on the substrate 2 to form the circuit of the electronic device 1.
• the substrate 2 is formed in a rectangular plate shape and is housed in the case 12 with the plate thickness direction extending vertically.
• Multiple through holes 21 are formed through the substrate 2, and terminals of multiple electronic components mounted on the substrate 2 are inserted into the through holes 21.
• the multiple electronic components are electrically connected to the wiring pattern of the substrate 2 by soldering the terminals inserted into the through holes 21.
• the substrate 2 is mounted with a control unit (not shown) including a plurality of circuit elements such as a CPU (Central Processing Unit), a semiconductor element 3, and a capacitor (not shown) as examples of a plurality of electronic components.
• the semiconductor element 3 is mounted on the mounting surface on the lower surface of the substrate 2, and has a resin-molded main body 31 and a plurality of lead terminals 32 extending from the main body 31 toward the substrate 2.
• the plurality of lead terminals 32 are inserted into through holes 21 from the lower side of the substrate 2 and are electrically connected to the wiring pattern of the substrate 2 by being soldered.
• the semiconductor element 3 is also provided with electrodes 33 exposed on the opposing surface (the lower surface in FIG. 1) facing the bottom wall 12E of the case 12 (see FIG. 5).
• Such a semiconductor element 3 can be configured, for example, as a field effect transistor (FET) constituting a regulator circuit or a switching element constituting an inverter circuit.
• FET field effect transistor
• the case 12 is a box-shaped member having an opening 13 that opens upward, and is formed from a metal such as aluminum or iron, for example.
• the case 12 has a front wall portion 12A, a rear wall portion 12B, a left wall portion 12C, a right wall portion 12D, and a bottom wall portion 12E.
• a first connector mounting portion 14 is formed in the left wall portion 12C of the case 12.
• the first connector mounting portion 14 is an opening that penetrates the left wall portion 12C and opens upward.
• a first connector 15 is mounted in the first connector mounting portion 14.
• the first connector 15 has a housing 15A and a plurality of connection terminals 15B provided on the housing 15A. One end of the plurality of connection terminals 15B is inserted into a through hole 21 from the lower side of the board 2 and is soldered to be electrically connected to the wiring pattern of the board 2.
• a cable connector that is electrically connected to the vehicle power source and on-board equipment (not shown) is connected to this first connector 15.
• a second connector mounting portion 16 is formed in the right wall portion 12D of the case 12.
• the second connector mounting portion 16 is an opening that penetrates the right wall portion 12D and opens upward.
• a second connector 17 is mounted in the second connector mounting portion 16.
• the second connector 17 has a housing 17A and a sensor terminal 17B provided in the housing 17A. One end of the sensor terminal 17B is inserted into a through hole 21 from the lower side of the board 2 and soldered to be electrically connected to the wiring pattern of the board 2.
• a cable connector that is electrically connected to various sensor devices mounted on the vehicle is connected to this second connector 17.
• a plurality of storage recesses 41, 42, 43 are formed in the bottom wall 12E of the case 12.
• a plurality of electronic components arranged on the lower side of the board 2 are accommodated in the plurality of storage recesses 41, 42, 43.
• a first storage recess 41 recessed in a substantially rectangular shape is formed on the left end side of the bottom wall 12E.
• the first storage recess 41 accommodates one end portion of the first connector 15 arranged in the case 12.
• a second storage recess 42 is formed on the right end side of the bottom wall 12E.
• the second storage recess 42 accommodates one end portion of the second connector 17 arranged in the case 12.
• a third storage recess 43 recessed in a substantially oval shape is formed on the center side of the bottom wall 12E adjacent to the first storage recess 41.
• the third storage recess 43 accommodates, for example, a capacitor (not shown) mounted on the board 2.
• a positioning portion 50 consisting of a pair of left and right protrusions 52, 52 is provided on the front end side of the bottom wall portion 12E. This positioning portion 50 is provided facing the mounting surface on the underside of the board 2, and during the manufacturing process, the semiconductor element 3 is placed on it before being mounted on the board 2. By placing the semiconductor element 3 on the positioning portion 50, it is positioned with respect to the board 2 which will be later housed in the case 12.
• the pair of protrusions 52, 52 are shaped like protrusions protruding from the bottom wall 12E and are spaced apart in the left-right direction.
• Each protrusion 52 has a first protrusion 521 that protrudes from the bottom wall 12E in the shape of a rectangular pedestal, and a second protrusion 522 that protrudes from the upper surface of the first protrusion 521 and is provided in a region higher than the height region of the first protrusion 521.
• This second protrusion 522 forms a protrusion that is approximately T-shaped in plan view.
• the two second protrusions 52, 52 are arranged symmetrically in the left-right direction and are configured to be convex toward each other toward the inside of the pair of protrusions 52, 52.
• Each board support part 18 is provided at the four corners of the bottom wall part 12E, standing upward from the bottom wall part 12E.
• Each board support part 18 forms a base surface for supporting the board in an area within the case 12 that is higher than the height area of the positioning part 50.
• the board 2 is placed at a distance from the bottom wall part 12E of the case 12 by being housed within the case 12 with its four corners placed on the four board support parts 18.
• the semiconductor element 3 shows a plan view of the semiconductor element 3 placed on the positioning portion 50 before being mounted on the substrate 2.
• the semiconductor element 3 has a resin-molded main body 31.
• a plurality of lead terminals 32 extend upward from the front end 31A and rear end 31B of the main body 31.
• a pair of positioned portions 34, 34 having a concave shape are formed on the left end 31C and right end 31D of the main body 31.
• the two positioned portions 34, 34 are formed by cutting out the left end 31C and right end 31D of the main body 31 into a substantially U-shaped shape in a plan view.
• the two positioned portions 34, 34 penetrate in the vertical direction.
• the two positioned portions 34, 34 are formed along the surface shape of the positioning portion 50 provided on the bottom wall portion 12E of the case 12, and in this embodiment, correspond to the convex shapes of the two second protrusions 522, 522.
• the left and right ends of the underside of the main body 31 of the semiconductor element 3 are placed on the upper surfaces of the first protrusions 521, 521 of the positioning section 50.
• the left and right ends 31C, 31D of the main body 31 closely face the inner surfaces of the second protrusions 522, 522, respectively.
• the convex portions of the second protrusions 52, 52 are inserted into the insides of the two positioned portions 34, 34 that are concave on the main body 31. This restricts movement of the semiconductor element 3 in the front-rear and left-right directions.
• the opening 13 of the case 12 is closed by a rectangular plate-shaped case cover 19.
• the case cover 19 is made of metal, such as aluminum or iron, for example.
• the case cover 19 is fixed to the upper ends of the front, back, left and right walls 12A to 12D of the case 12 using adhesive, screws, or the like.
• an accommodation space is formed inside the case 12. This accommodation space is sealed by filling it with potting resin (not shown) after the board 2 and multiple electronic components mounted on the board 2 are accommodated inside the case 12.
• the manufacturing process of the electronic device 1 will be described with reference to Figures 4(A) to 4(D).
• the substrate 2 and the multiple electronic components mounted on the substrate 2 are housed in the case 12, and the substrate 2 and the lead terminals of the multiple electronic components are connected by soldering.
• the first connector 15, the second connector 17, a capacitor (not shown), the semiconductor element 3, and other electronic components are arranged on the lower side of the substrate 2.
• the first connector 15, the second connector 17, and the capacitor are accommodated in the first accommodating recess 41 to the third accommodating recess 43 formed in the bottom wall portion 12E of the case 12, and are positioned relative to the substrate 2 that will be accommodated later.
• the semiconductor element 3 is positioned relative to the substrate 2 to be housed later by the positioning portion 50 provided on the bottom wall portion 12E of the case 12. Specifically, both left and right end sides of the main body portion 31 of the semiconductor element 3 are placed on the first protrusions 521, 521 of the positioning portion 50, and the convex portions of the second protrusions 522, 522 of the positioning portion 50 are inserted inside the positioned portions 34, 34 of the main body portion 31. In this state, the first protrusion 521 of the positioning portion 50 supports the semiconductor element 3 in a state separated from the bottom wall portion 12E of the case 12. In addition, the second protrusions 522, 522 restrict movement of the semiconductor element 3 in the front-rear and left-right directions.
• the board 2 is placed on top of the electronic components in the case 12.
• the board 2 is supported at a predetermined height by the four board supports 18 in the case 12.
• the terminals (32, 15B, 17B) extending from the electronic components on the lower side of the board 2 are inserted into the through holes 21 of the board 2.
• a clearance is provided between the body 31 of the semiconductor element 3 and the board 2 to allow the semiconductor element 3 to move in the height direction. Therefore, the semiconductor element 3 is positioned relative to the board 2 by the positioning part 50 when viewed from the overlapping direction with the board 2 (vertical direction), but movement in the height direction along the overlapping direction is allowed.
• the tips of the lead terminals 32 of the semiconductor element 3 are arranged in a height region that does not protrude from the top surface of the board 2.
• a flow soldering process is performed to mount multiple electronic components housed in the case 12 on the board 2.
• the board 2 inside the case 12 is pressed from above with a jig 62, and the orientation of the case 12 is inverted vertically.
• the semiconductor element 3 moves in the height direction using its own weight and abuts against the underside of the board 2. This movement is guided by the second protrusions 522, 522 of the positioning portion 50 and the through holes 21 of the board 2, and is guided to an appropriate position on the board 2.
• the lead terminals 32 of the semiconductor element 3 are positioned in a height region that protrudes from the top surface of the board 2.
• solder 60 melted in a soldering furnace is jetted from the lower side of the upside-down case 12 toward the upper surface of the board 2 (the lower surface in FIG. 4(C)).
• This process connects the terminals (32, 15B, 17B) inserted into the through holes 21 of the board 2 to the wiring pattern formed on the board 2.
• the soldering of multiple electronic components arranged on the lower side of the board 2 can be completed with a single flow soldering process.
• FIG. 5 shows a cross section of the electronic device 1 manufactured through the steps of FIGS. 4(A)-(D) cut in the left-right and top-bottom directions.
• the semiconductor element 3 is disposed in the case 12 at a distance from the bottom wall portion 12E that constitutes the surface facing the substrate 2.
• the first clearance formed between the semiconductor element 3 and the bottom wall portion 12E is indicated by the symbol "T1".
• the distance of this first clearance T1 is desirably a distance necessary to ensure an insulating distance between the semiconductor element 3 and the case 12. This makes it possible to avoid the need to insert a sheet-like insulating member to ensure insulation between the case 12 and the semiconductor element 3.
• the semiconductor element 3 is also arranged in a state separated from the positioning portion 50 protruding from the bottom wall portion 12E of the case 12. Specifically, the lower surface of the body portion 31 of the semiconductor element 3 is also arranged in a state separated from the upper surface of the first protrusions 521, 521 of the positioning portion 50.
• the second clearance formed between the semiconductor element 3 and the first protrusions 521, 521 is indicated by the symbol "T2".
• This second clearance T2 makes the first clearance T1 formed between the semiconductor element 3 and the bottom wall portion 12E larger, making it easier to spread the potting resin to the lower side of the semiconductor element 3 surrounded by the positioning portion 50. As a result, air pockets are less likely to occur between the semiconductor element 3 and the bottom wall portion 12E, and the heat dissipation efficiency of the semiconductor element 3 can be improved.
• the bottom wall 12E of the case 12 constitutes an opposing surface that faces the mounting surface on the lower surface of the substrate 2.
• a semiconductor element 3 is mounted on the mounting surface on the lower surface of the substrate 2 as an electronic component.
• the case 12 has a positioning portion 50 on the bottom wall 12E, and this positioning portion 50 can position and arrange the semiconductor element 3 before the semiconductor element 3 is mounted on the substrate 2. Therefore, in the electronic device 1, the semiconductor element 3 can be positioned with respect to the substrate 2 that will be accommodated later, without having to be fixed in the case 12 by screws.
• the semiconductor element 3 is positioned by the positioning portion 50 and then placed inside the case 12.
• the substrate 2 is then placed on top of the semiconductor element 3 from above, so that the lead terminals 32 of the semiconductor element 3 are inserted into the through holes 21 of the substrate 2. In this way, it is possible to easily position the substrate 2 and the semiconductor element 3, and also to reduce manufacturing costs.
• the positioning portion 50 has a protruding shape that protrudes from the bottom wall portion 12E of the case 12, and allows the semiconductor element 3 to be positioned and arranged in a state separated from the bottom wall portion 12E of the case 12 before the semiconductor element 3 is mounted on the substrate 2. Therefore, the semiconductor element 3 is positioned relative to the substrate 2, and at the same time, an insulating distance with the case 12 can be secured by the first clearance T1 provided between the semiconductor element 3 and the case 12. As a result, it is possible to eliminate the need to place a sheet-like insulating member between the semiconductor element 3 and the case 12, making manufacturing easier.
• the present invention is not limited to the above embodiment, and a positioning portion 70 shown in FIG. 6A may be applied instead of the positioning portion 50.
• the positioning portion 70 is composed of a pair of protrusions 72 protruding from the bottom wall portion 12E of the case 12.
• Each protrusion 72 has a first protrusion 721 protruding from the bottom wall portion 12E in a rectangular pedestal shape, and a second protrusion 722 protruding from the upper surface of the first protrusion 721 and provided in a region higher than the height region of the first protrusion 721.
• the second protrusion 722 is composed of a pin protruding upward and corresponds to a positioned portion 78 formed in the main body portion 76 of the semiconductor element 74.
• the positioned portion 78 is composed of a through hole that penetrates the main body portion 76 in the vertical direction.
• the semiconductor element 74 After mounting on the board, the semiconductor element 74 has a first clearance T1 between it and the bottom wall portion 12E of the case 12, similar to the above embodiment. In addition, the semiconductor element 74 has a second clearance T2 between it and the positioning portion 70. Therefore, the same effect as the above embodiment can be achieved.
• the present invention is not limited to the above embodiment, and a positioning portion 80 shown in FIG. 7A may be applied instead of the positioning portion 50.
• the positioning portion 80 is configured as a recess formed in the bottom wall portion 12E of the case 12.
• the positioning portion 80 has a recess 82 that is recessed in a substantially rectangular shape in a plan view, and a pair of first protrusions 821 that protrude upward from the bottom surface of the recess 82 inside the recess 82.
• the semiconductor element 84 has a resin-molded main body portion 86 housed in the recess 82 together with the lead terminals 32.
• the semiconductor element 84 is disposed in a state separated from the bottom surface of the recess 82 by placing the left and right ends of the main body portion 86 on the pair of first protrusions 821.
• the semiconductor element 84 after mounting on the board, the semiconductor element 84 is provided with a first clearance T1 between it and the bottom wall portion 12E of the case 12, similar to the above embodiment.
• the semiconductor element 84 is provided with a second clearance T2 between it and the positioning portion 80. Therefore, the same effects as those of the above embodiment can be achieved. [supplementary explanation]
• the semiconductor elements 3, 74, and 84 according to the above-mentioned embodiments are configured so that the electrodes 33 are exposed on the surface of the main body 31, 76, and 86, but this is not limited thereto.
• the electrodes may not be exposed on the surface of the main body, as in a so-called full mold package.
• the first protrusions 521, 721, and 821 may be omitted from the configurations of the positioning parts 50, 70, and 80 according to the above-mentioned embodiments and modifications.
• the configuration may be such that no clearance (first clearance) is provided between the semiconductor element and the bottom wall part 12E of the case 12.
• the configuration is such that a clearance (second clearance T2) is provided between the semiconductor element and the positioning part, but the configuration may be such that no clearance is provided.
• the inside of the case 12 is sealed with potting resin, but the present invention is not limited to this.
• the inside of the case 12 may not be sealed with potting resin.
• the opening 13 of the case 12 is closed by the case cover 19, but the case cover 19 may not be provided.

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• Engineering & Computer Science (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Manufacturing & Machinery (AREA)
• Mechanical Engineering (AREA)
• Structures For Mounting Electric Components On Printed Circuit Boards (AREA)

Priority Applications (3)

Applications Claiming Priority (1)

Publications (1)

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Family Applications (1)

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Citations (5)

• 2022
  • 2022-11-25 JP JP2024559837A patent/JPWO2024111132A1/ja active Pending
  • 2022-11-25 CN CN202280102060.7A patent/CN120266584A/zh active Pending
  • 2022-11-25 WO PCT/JP2022/043638 patent/WO2024111132A1/ja not_active Ceased

Patent Citations (5)

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