JP2017135233A - Electronic circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic circuit board with high reliability such that an influence of thermal stress is reduced and electric and mechanical connection between an electronic element and a metal plate is not spoiled.SOLUTION: The present invention relates to an electronic circuit board 10 comprising a metal plate 12 formed according to a wiring pattern and an insulation member 3 molded with the metal plate 12 held therein. The insulation member 3 partially has an opening part 3h where the insulation member 3 is absent, and the metal plate 12 has a connection part 12c having a mount surface 12m for connecting an electronic component 5 to the metal plate 12 exposed in the opening part 3h, and a bent part 12b formed by the bending the metal plate 12 such that the mount surface 12m is at a different height position from the metal plate 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic circuit board, and is particularly suitable for application to an injection-molded board provided with a large current circuit corresponding to large current and high heat dissipation such as an inverter circuit and a power supply circuit.

  Conventionally, for electronic circuit boards, a metal foil is cut according to a wiring pattern, and a printed board laminated with an insulating layer, and a metal plate (for example, a copper plate) is cut according to the wiring pattern and integrally molded with an insulating resin. There is.

  In a printed circuit board, when stress that concentrates on the electronic component to be mounted and the connection part between the component boards is relieved, it is difficult to provide a stress relieving part on the board side (increased cost and difficulty in manufacturing). It was common to provide a relaxation part.

  An electronic component having a package structure has been proposed as an electronic component in which a stress relaxation portion is provided on the component side (see, for example, Patent Document 1). In this electronic component, a crystal resonator housed in a cavity formed inside by a base and a lid, an electrode of the crystal resonator, and a through electrode of a through hole penetrating the base are connected, and the through electrode The lead terminal is connected, and a bent portion (stress relieving portion) is formed between one end and the other end of the lead terminal.

  On the other hand, as shown in FIG. 13, an injection-molded substrate 1 includes a metal plate 2 made of a circuit conductor formed according to a wiring pattern, and an insulating member 3 molded with the metal plate 2 sandwiched between insulating resins. And an electronic element 5 connected to the metal plate 2. The metal plate 2 is used as a so-called bus bar in the electronic circuit board 1.

  The insulating member 3 has an opening 3a composed of a through-hole in which the insulating member 3 does not exist in a part of the insulating member 3, and the two metal plates 2 are exposed in a state of being opposed to each other in the opening 3a. Yes. The front surfaces of the two metal plates 2 are used as one (left side) connection surface 2m and the other (right side) connection surface 2m for mounting and connecting the electronic elements 5. The electronic elements 5 are placed so as to straddle the connection surfaces 2m of the two metal plates 2, respectively, and one (left side) electrode 5b and the other (right side) electrode 5b of the electronic element 5 and the metal plate 2 One (left side) connection surface 2 m and the other (right side) connection surface 2 m are electrically connected by solder 4.

JP 2010-199678 A (page 4, FIG. 1)

  The injection-molded substrate 1 having such a configuration expands when the apparatus on which the injection-molded substrate 1 is mounted is used, or contracts when the device is not used. The thermal expansion coefficient and the thermal expansion coefficient of the electronic element 5 are different from each other. Therefore, since the degree of expansion of the metal plate 2 and the degree of expansion of the electronic element 5 are different, the solder 4 is affected by thermal stress, and the solder 4 may be cracked. When a crack occurs in the solder 4, the mechanical and electrical connection between the metal plate 2 and the electronic element 5 is impaired.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an electronic circuit board having high reliability without damaging the electrical and mechanical connection between the electronic element and the metal plate. That is.

  To achieve the above object, the present invention provides an electronic circuit board comprising a metal plate that forms a circuit conductor and an insulating member that is molded with the metal plate sandwiched therebetween, An opening having a portion where no insulating member is present, and the metal plate is opposed to each other with the opening interposed therebetween, one and the other bases sandwiched between the insulating members, and an electronic element One and the other connecting portions exposed to the openings so that they do not come into contact with each other in a state of facing each other with the openings interposed therebetween. And the metal plate is bent so that the connection portion is at a height position different from the base portion, and one and the other bent portions connecting the base portion and the connection portion, respectively. .

  In this invention, the said connection surface is set to the height corresponding to the surface of the said insulating member according to the bending state of the said bending part.

  In the present invention, the bent portion is not in contact with the insulating member.

  In the present invention, the connection portion has an outflow prevention structure for preventing the solder from flowing out to the bent portion on the connection surface.

  In the present invention, one electrode of the electronic element is connected to the one connection surface, and the other electrode of the electronic element is connected to the other connection surface, The other connection surface is mechanically and electrically connected by the electronic element.

  In the present invention, when the insulating member is laminated with an insulating member of another electronic circuit board, the connection surfaces are connected to each other.

  In the present invention, the connection portions are electrically connected to each other via solder between the connection surfaces.

  In the present invention, the connection portions are thermally connected to each other via a heat conductive sheet between the connection surfaces.

  In the present invention, the bent portion is a portion in which a part of the base portion of the metal plate protruding from the insulating member to the opening so as to face each other is cut and bent, and the opening of the portion The amount of protrusion with respect to is less than half of the length of the opening along the longitudinal direction of the metal plate.

  According to the present invention, it is possible to realize an electronic circuit board having high reliability without damaging the electrical and mechanical connection between the electronic element and the metal plate.

It is the fragmentary sectional view, enlarged sectional view, and top view which show the structure of the electronic circuit board which concerns on 1st Embodiment. It is a basic diagram which shows the relationship between the bending angle (alpha) of the bending part of the electronic circuit board in 1st Embodiment, the gap g, and the height h of a connection part (connection surface). It is a fragmentary sectional view which shows the bending state of the bending part of the electronic circuit board in 1st Embodiment. It is a fragmentary sectional view which shows the relationship between the length of the metal plate of the electronic circuit board in 1st Embodiment, and the opening length D of an opening part. It is an expanded sectional view showing solder flow prevention structure of an electronic circuit board in a 1st embodiment. It is a fragmentary sectional view which shows the stress relaxation state when it receives to the influence of the thermal stress in the electronic circuit board in 1st Embodiment. It is a fragmentary sectional view which shows the application | coating state of the solder using the metal mask of the electronic circuit board in 1st Embodiment. It is a fragmentary sectional view which shows the electrical interlayer connection state of the electronic circuit board in 1st Embodiment. It is a fragmentary sectional view which shows the thermal interlayer connection state of the electronic circuit board in 1st Embodiment. It is a fragmentary sectional view which shows the structure of the electronic circuit board in 2nd Embodiment. It is a fragmentary sectional view which shows the structure of the electronic circuit board in 3rd Embodiment. It is the fragmentary sectional view and top view which show the structure of the electronic circuit board in 4th Embodiment. It is a fragmentary sectional view which shows the state when it receives to the influence of the structure of a conventional electronic circuit board, and a thermal stress.

  Hereinafter, the first to fourth embodiments of the present invention will be described with reference to the drawings. In addition, the 1st thru | or 4th embodiment described below is an illustration to the last, and can take a various form in the scope of the present invention.

<First Embodiment>
<Configuration of electronic circuit board>
The electronic circuit board 10 according to the first embodiment will be described with reference to FIGS. 1 to 9. Here, in the figure, the longitudinal direction of the metal plate 12 of the electronic circuit board 10 is defined as the board horizontal direction (arrow ab direction), the arrow a direction is defined as the left side, and the arrow b direction is defined as the right side. In the figure, the direction in which the metal plate 2 and the insulating member 3 of the electronic circuit board 10 are overlapped is defined as the substrate vertical direction (arrow cd direction), the arrow c direction is defined as the upper side, and the arrow d direction is defined as the lower side.

  FIG. 1A is a partial cross-sectional view showing the configuration of the electronic circuit board 10 according to the first embodiment, and FIG. 1B is an enlarged cross-sectional view of the bent portion 12b. FIG. 1C is a top view of the electronic circuit board 10 to which the electronic element 5 is not connected. 1A and 1B are a partial cross-sectional view and an enlarged cross-sectional view corresponding to the XX cross section in FIG. 1C.

  As shown in FIGS. 1A to 1C, the electronic circuit board 10 is an injection-molded board, and includes an insulating member 3, a metal plate 12, and an electronic element 5. The insulating member 3 is made of an insulating resin having insulation properties and high heat resistance such as PPS (polyphenylene sulfide), and is molded with the metal plate 12 sandwiched from above and below. is there. The insulating member 3 has an opening 3h made of a through hole in which the insulating member 3 does not exist.

  The electronic element 5 is, for example, a chip capacitor, a chip resistor, or the like, and includes an element body 5a and one (left side) electrode 5b and the other (right side) electrode 5b provided on each of the left and right sides of the element body 5a. It is configured. The electronic element 5 is electrically and mechanically connected to the metal plate 12. Specifically, the electrode 5b on one (left side) of the electronic element 5 and the connection surface 12m of the connection part 12c on one (left side) of the metal plate 12 are electrically connected by the solder 4, and the other ( The electrode 5 b on the right side and the connection surface 12 m of the connection part 12 c on the other side (right side) of the metal plate 12 are electrically connected by the solder 4.

  The metal plate 12 is used as a so-called bus bar, and is a circuit conductor formed by punching a steel plate with a press die in accordance with a wiring pattern. The metal plate 12 has one (left side) and the other (right side) base part 12a, one and the other bent part 12b, and one and the other connection part 12c arranged opposite to each other with the opening 3h interposed therebetween. And is bent into a substantially S shape toward the tip as a whole. That is, each of the one (left side) metal plate 12 and the other (right side) metal plate 12 includes the base 12a, the bent portion 12b, and the connecting portion 12c, and is the same only in the reverse direction. Since it is a structure, here, for convenience, the left metal plate 12 will be mainly described.

  The base 12a of the metal plate 12 is a portion extending to the right side (arrow b direction) from the insulating member 3 toward the opening 3h while being sandwiched between the upper insulating member 3 and the lower insulating member 3. The tip is exposed in the opening 3h.

  The bent portion 12b of the metal plate 12 is a portion that connects the base portion 12a and the connecting portion 12c. The bent portion 12b includes a bent portion 12ba bent toward the upper side (in the direction of arrow c) at the tip of the base portion 12a, and a straight portion extending linearly obliquely from the bent portion 12ba toward the upper side (in the direction of arrow c). 12bs and a bent portion 12bc bent toward the right side (arrow b direction) at the upper end (arrow c direction) end of the straight portion 12bs.

  The bent portion 12b is bent by the bent portion 12ba and the bent portion 12bc so that the base portion 12a and the connecting surface 12m of the connecting portion 12c are at different height positions in the substrate vertical direction. Specifically, the bent portion 12ba of the bent portion 12 and the connecting surface 12m of the connecting portion 12c and the exposed surface 3m of the insulating member 3 are the same height position in the substrate vertical direction, that is, flush with each other. The bent portion 12bc is bent.

  However, the connection surface 12m of the connection part 12c and the exposed surface 3m of the insulating member 3 do not necessarily have to be completely at the same height, and the connection surface 12m of the connection part 12c is exposed to the exposed surface 3m of the insulating member 3. Even if it has the recessed part slightly dented from, you may have the convex-shaped convex part which protruded slightly.

  Here, the depth of the recess when the connection surface 12m of the connection portion 12c is slightly recessed from the exposed surface 3m of the insulating member 3 is, for example, within 30 μm. The reason why the depth of the concave portion is 30 μm is that the variation in the amount of solder when applying solder with a metal mask MM (see FIG. 7) described later can be suppressed to a low level.

  Further, the height of the protrusion when the connection surface 12m of the connection portion 12c slightly protrudes from the surface 3m is, for example, 100 μm to 200 μm, which is thinner than the thickness of the metal mask MM described later. The reason for setting the height of the convex portion to 100 μm to 200 μm is that the solder can be applied uniformly if the height of the convex portion is thinner than the thickness of the metal mask MM.

  That is, the height of the connection surface 12m of the connection portion 12c may be a height corresponding to the surface 3m of the insulating member 3, that is, within a range of −30 μm to 200 μm. However, more preferably, the connection surface 12m of the connection part 12c and the exposed surface 3m of the insulating member 3 have the same height in the substrate vertical direction.

  The connecting portion 12c of the metal plate 12 is a portion extending linearly from the bent portion 12bc of the bent portion 12b toward the right side (in the direction of arrow b), and the upper surface (in the direction of arrow c) has the electronic element 5 mounted thereon. The connecting surface 12m is electrically and mechanically connected. Therefore, when the electronic element 5 is placed and connected, the connection surface 12m of the one (left side) connection part 12c and the connection surface 12m of the other (right side) connection part 12c are either The (left) connecting surface 12m and the other (right) connecting surface 12m are mechanically and electrically connected.

  The left metal plate 12 and the right metal plate 12 are disposed so as to face each other with the opening 3h interposed therebetween. Further, the left metal plate 12 and the right metal plate 12 are exposed in the opening 3h in a state in which a certain gap g is provided so that the left and right connection portions 12c do not contact each other. The gap g is set in advance according to the distance between the one (left side) electrode 5b and the other (right side) electrode 5b in the electronic element 5.

  As shown in FIGS. 2A and 2B, the metal plate 12 has a bending angle α of the straight portion 12bs with respect to the base portion 12a via the bent portion 12ba and a straight portion 12bs via the bent portion 12bc. The bending angle β (β = 180 ° −α) of the connecting portion 12c is defined, and the bent state of the bent portion 12b is set by the bending angles α and β.

  For example, the bent portion 12b can bend the straight portion 12bs with respect to the base portion 12a at a bending angle α (= 90 °) or an arbitrary bending angle α less than that. When the straight portion 12bs is bent at a bending angle α (= 90 °) with respect to the base portion 12a, the size of the gap g between the one (left side) connecting portion 12c and the other (right side) connecting portion 12c is the maximum value. The height h from the base portion 12a to the connection portion 12c is the maximum value h1. In this case, as shown in FIG. 3A, the bent portion 12b of the metal plate 12 is bent at a right angle with respect to the base portion 12a and the connecting portion 12c.

  Further, the bent portion 12b can bend the straight portion 12bs with respect to the base portion 12a at a bending angle α (= 60 °). When the straight portion 12bs is bent at a bending angle α (= 60 °) with respect to the base portion 12a, the size of the gap g becomes a value g2 smaller than the maximum value g1, and the height from the base portion 12a to the connection portion 12c is high. The length h is also a value h2 smaller than the maximum value h1. In this case, as shown in FIG. 3B, the bent portion 12b of the metal plate 12 is bent at about 60 ° with respect to the base portion 12a.

  That is, regarding the gap g between the one (left side) metal plate 12 and the other (right side) metal plate 12 and the height h from the base portion 12a to the connection portion 12c, the bending portion 12b with respect to the base portion 12a It can be freely set according to the bending angle α of the straight portion 12bs and the bending angle β of the connecting portion 12c with respect to the straight portion 12bs. Even if the bent portion 12b is bent at a bending angle α (= 90 °) with respect to the base portion 12a, the opening end surface 3a of the opening 3h of the insulating member 3 and the straight portion 12bs of the metal plate 12 are used. Is non-contact.

  In this way, the bent portion 12b of the metal plate 12 is bent into a substantially S shape including the bent portion 12ba, the straight portion 12bs, and the bent portion 12bc, and the opening end surface of the opening 3h of the insulating member 3 It has a non-contact configuration with 3a. Therefore, since the bent portion 12b is not restricted from moving in the horizontal direction (arrow ab direction), the solder 4 connecting the connecting portion 12c of the metal plate 12 and the electronic element 5 is affected by thermal stress. In this case, it functions as a stress relaxation part that relaxes the influence of thermal stress on the solder 4.

  Further, as shown in FIGS. 4A and 4B, the metal when the bent portion 12b has a bending angle α (= 0 degree) with respect to the base portion 12a, that is, when the bent portion 12b is not bent. The length of the plate 12 is set as follows. The maximum protrusion amount Lmax from the opening end surface 3a of the opening 3h of the insulating member 3 to the tip of the metal plate 12 is the length D / from the opening end surface 3a to the center C of the horizontal opening length D of the opening 3h. It is 2 or less, and is expressed by the following formula 1.

Lmax ≦ D / 2 ……………………………………………………………………… (Equation 1)

  This means that one (left side) metal plate 12 and the other (right side) metal plate 12 can be formed by being bent after one steel plate is cut. That is, since two steel plates are not required and the steel plate can be formed from one steel plate, the cost can be reduced.

  Further, when the bent portion 12b has a bending angle α (≧ 0 °) with respect to the base portion 12a, the one (left side) metal plate 12 and the other (right side) metal plate 12 have openings in the insulating member 3. The protruding amount L1 from the opening end surface 3a of 3h to the tip of the connecting portion 12c is not more than the maximum protruding amount Lmax, and the gap g is not less than 0.

  Subsequently, as shown in FIG. 5A, in the connection portion 12c of the metal plate 12, the connection surface 12m that is electrically and mechanically connected to the electronic element 5 is slightly recessed from the connection surface 12m. A step surface 12d is formed. In this case, the connecting surface 12m of the connecting portion 12c and the exposed surface 3m of the insulating member 3 are at the same height, but the stepped surface 12d is located below the surface 3m in the substrate vertical direction (arrow cd direction) ( The height position is slightly recessed in the direction of arrow d).

  The step surface 12d of the connection portion 12c functions as a connection surface of the electronic element 5 and also functions as a solder 4 application surface. Further, the end portion of the connection portion 12c where the connection surface 12m is left functions as a dam portion protruding upward in the substrate vertical direction from the step surface 12d. The weir portion has a solder flow prevention structure for preventing an unexpected short circuit due to the solder 4 flowing out to the bent portion 12b when the solder 4 has good wettability.

  In this case, the stepped surface 12d of the connecting portion 12c is set at the same height as the surface 3m of the insulating member 3. However, the present invention is not limited to this, and the connecting surface 12m of the connecting portion 12c You may set to the same height position as the surface 3m. In this case, the step surface 12d is at a height position slightly recessed from the surface 3m of the insulating member 3.

  However, the solder flow prevention structure is not limited to this, and various other variations are conceivable. For example, as shown in FIG. 5B, a recess 12e having a predetermined depth may be provided at the left end portion of the connection surface 12m of the connection portion 12c as a solder flow prevention structure. When the wettability of the solder 4 is good, the recess 12e functions as a reservoir for the solder 4 for preventing an unexpected short circuit due to the solder 4 flowing out to the bent portion 12b.

  Further, as shown in FIG. 5C, a through hole 12f may be provided at the left end of the connection surface 12m of the connection part 12c as a solder flow prevention structure. In this case, even if the wettability of the solder 4 is good, the solder 4 is a viscous liquid and is attached to the through hole 12f by the action of surface tension. Thus, the through-hole 12f functions as a path blocking portion for the solder 4 for preventing an unexpected short circuit due to the solder 4 all flowing out to the bent portion 12b.

  As shown in FIG. 5D, as the solder flow prevention structure, a convex portion 12g that protrudes upward may be provided between the bent portion 12b and the connecting portion 12c. When the wettability of the solder 4 is good, the convex portion 12g functions as a dam portion that prevents an unexpected short circuit due to the solder 4 flowing out to the bent portion 12b. The convex portion 12g can be formed by bending the metal plate 12 with a press die.

  As shown in FIG. 5 (E), a concave protrusion 12h may be provided between the bent portion 12b and the connecting portion 12c as a solder flow prevention structure. When the wettability of the solder 4 is good, the convex protrusion 12h functions as a reservoir for the solder 4 for preventing an unexpected short circuit due to the solder 4 flowing out to the bent portion 12b. . The protruding protrusion 12g can be formed by bending the metal plate 12 with a press die.

  In the above configuration, one (left side) and the other (right side) metal plate 12 of the electronic circuit board 10 each have a bent portion 12b that functions as a stress relaxation portion, as shown in FIG. Yes. As a result, even when one and the other metal plate 12 or the electronic element 5 expands or contracts to generate thermal stress, the bent portion 12b is bent as shown in FIG. 6B or 6C. Since it can fall to the right side or the left side via the parts 12ba and 12bc, the influence of thermal stress on the solder 4 can be absorbed.

  Thus, in the electronic circuit board 10, since the influence of the thermal stress on the solder 4 can be mitigated by the bent portions 12b of the one and the other metal plates 12, it is possible to prevent the solder 4 from cracking. The mechanical and electrical connection between the one and the other metal plate 12 and the electronic element 5 can be maintained.

  Moreover, the electronic circuit board 10 made the surface 3m of the insulating member 3 and the connection surface 12m of the connection part 12c of the metal plate 12 the same height, and was made flush. As a result, as shown in FIG. 7, with the metal mask MM placed on the surface 3m of the insulating member 3, the solder 4 is entirely applied to the surface of the metal mask MM, and the solder 4 is metalized with a squeegee SK. The through holes of the mask MM are filled, and the solder 4 can be uniformly and collectively transferred onto the connection surface 12m of the connection portion 12c of the metal plate 12. Accordingly, when the height of the surface 3m of the insulating member 3 and the connection surface 12m of the connection portion 12c of the metal plate 12 are not uniform, the manufacturing efficiency is markedly higher than when the solder 4 is individually applied using a solder dispenser. Can be improved.

  The metal plate 12 includes the bent portion 12b including the bent portion 12ba, the straight portion 12bs, and the bent portion 12bc, so that the electronic element can be viewed from the upper side (arrow c direction) in the substrate vertical direction (arrow cd direction). The bending portion 12b has a rigidity that does not easily bend even with respect to an external force applied to the motor 5. Thereby, the electronic circuit board 10 can maintain the height positions of the surface 3 m of the insulating member 3 and the connection surface 12 m of the connection portion 12 c of the metal plate 12. Thus, when the solder 4 is applied to the connection surface 12m of the connection portion 12c via the metal mask MM and the squeegee SK, the electronic circuit board 10 prevents the transfer amount of the solder 4 from varying and transfers it uniformly. be able to.

  Subsequently, as shown in FIG. 8A, the connection part 12c of the metal plate 12 in the lower electronic circuit board 10 and the connection part 12c of the metal plate 12 in the upper electronic circuit board 10 are in close contact with each other. It can be laminated in the direction perpendicular to the substrate (arrow cd direction) by arranging in the direction and reflowing the connection surfaces 12m of the connection part 12c with the solder 4.

  In this case, since the connection surface 12m of the connection part 12c and the surface 3m of the insulating member 3 are set to be flush with each other, the coating is applied between the lower connection part 12c and the upper connection part 12c. The amount of solder 4 applied is minimal. Thus, in the electronic circuit board 10, since the connection surface 12m of the connection part 12c and the surface 3m of the insulating member 3 are set to be flush with each other, the thickness in the vertical direction of the substrate is minimized. The electronic circuit board 10 can be laminated with excellent space efficiency.

  As shown in FIG. 8B, the upper and lower electronic circuit boards 10s having a configuration in which the connection portions 12cs of one (left side) and the other (right side) metal plate 12s are integrated are used. The connection part 12cs of the metal plate 12s in the lower electronic circuit board 10s and the connection part 12cs of the metal plate 12s in the upper electronic circuit board 10s are arranged so as to be in close contact with each other, and the connection surfaces 12ms of the connection part 12cs are in contact with each other. Can also be connected by solder 4.

  Further, as shown in FIG. 9, the connection part 12c of the metal plate 12 in the lower electronic circuit board 10 and the connection part 12c of the metal plate 12 in the upper electronic circuit board 10 are arranged so as to be in close contact with each other. The heat conduction sheet HCS made of, for example, silicone or acrylic can be sandwiched between the connection surfaces 12m of the connection part 12c. In this case, the thickness of the metal plate 12 may be reduced by the thickness of the heat conductive sheet HCS. Specifically, the thickness of the upper metal plate 12 and the thickness of the lower metal plate 12 may be set to be 1/2 each of the thickness of the heat conductive sheet HCS.

  In this case, the lower electronic circuit board 10 and the upper electronic circuit board 10 can be thermally connected via the heat conductive sheet HCS. Thus, a heat dissipation path is added so that heat generated in the lower electronic circuit board 10 and heat generated from the electronic element ep provided between the insulating members 3 are radiated from the upper electronic circuit board 10. Can do. Thus, since the connection surface 12m of the connection part 12c and the surface 3m of the insulating member 3 are set at the same height position, the lower electronic circuit board 10 and the upper electronic circuit board 10 are connected to the heat conductive sheet. It is easy to thermally connect via the HCS, and a form that efficiently dissipates heat can be constructed.

  According to the above configuration, the influence of the thermal stress on the solder 4 can be alleviated by the bent portions 12b of the one and the other metal plates 12, and cracks in the solder 4 can be prevented in advance. It is possible to realize the electronic circuit board 10 having high reliability without damaging the electrical and mechanical connection between the element 5 and the one and other metal plates 12.

<Second Embodiment>
As shown in FIG. 10 in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, the electronic circuit board 20 in the second embodiment is different from the metal plate 12 of the electronic circuit board 10 in the first embodiment. It has the metal plate 22 of a different shape, It is characterized by the above-mentioned. In the second embodiment, the same components as those of the insulating member 3, the solder 4, and the electronic element 5 shown in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. .

  The metal plate 22 of the electronic circuit board 20 has a bent portion 22b bent at bending angles α and β perpendicular to the base portion 22a and the connecting portion 22c, and the bent portion 22b is formed on the opening end surface 3a of the insulating member 3. In contact. The electronic circuit board 20 has the same configuration as the electronic circuit board 10 except for the metal plate 22.

  In this case, the bent portion 22b of the metal plate 22 is in contact with the open end surface 3a of the insulating member 3, but is not in contact with the substrate horizontal direction, so that the metal plates 22 are separated from each other. Only when the electronic element 5 contracts or the electronic element 5 contracts, the bent portion 22b falls down so that the connecting portions 22c approach each other along the substrate horizontal direction, and the influence of thermal stress on the solder 4 can be absorbed.

<Third Embodiment>
As shown in FIG. 11 in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, the electronic circuit board 30 in the third embodiment is different from the metal plate 12 in the electronic circuit board 10 in the first embodiment. It has the metal plate 32 of a different shape, It is characterized by the above-mentioned. In the third embodiment, the same components as those of the insulating member 3, the solder 4, and the electronic element 5 shown in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. .

  The metal plate 32 of the electronic circuit board 30 includes a base portion 32a, a bent portion 32b, and a connection portion 32c. The base portion 32 a is a portion extending in the horizontal direction while being sandwiched between the upper insulating member 3 and the lower insulating member 3, and the tip thereof is exposed to the opening 3 h of the insulating member 3.

  The bent portion 32b is a portion that connects the base portion 32a and the connecting portion 32c. The bent portion 32b includes a bent portion 32ba bent at the tip of the base portion 32a, a straight portion 32bs extending vertically from the bent portion 32ba toward the upper side (arrow c direction), and an upper side of the straight portion (arrow c direction). ) And a bent portion 32bc bent at the end.

  The bent portion 32b is bent at two bent portions 32ba and 32bc so that the base portion 32a and the connection surface 32m of the connection portion 32c are at different height positions in the substrate vertical direction. Specifically, the bent portion 32ba of the bent portion 32b, so that the connection surface 32m of the connection portion 32c and the exposed surface 3m of the insulating member 3 are at the same height position in the substrate vertical direction, that is, flush with each other. 32bc is bent.

  However, the connection surface 32m of the connection portion 32c and the exposed surface 3m of the insulating member 3 are not necessarily at the same height, and the connection surface of the connection portion 32c is from the exposed surface 3m of the insulating member 3. It may be slightly recessed or slightly protruding.

  The connecting portion 32c is a portion extending linearly so as to return from the bent portion 32bc of the bent portion 32b toward the insulating member 3, and the upper surface (in the direction of the arrow c) is placed on the electronic element 5 to be electrically connected. The connection surface 32m is connected mechanically and mechanically.

  In this case, the tip of the metal plate 12 in the first embodiment is substantially S-shaped, whereas the tip of the metal plate 32 in the third embodiment is substantially U-shaped. The functions of the plates 12 and 32 are the same. However, in the electronic circuit board 30 in the third embodiment, two metal plates 32 are not formed from one steel plate, but two metal plates 32 are formed from two steel plates. However, the present invention is not limited to this, and the two metal plates 32 may be formed from one steel plate when the interval between the bent portions 32b can be further expanded.

<Fourth embodiment>
As shown in FIG. 12, in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, the electronic circuit board 40 in the fourth embodiment is different from the metal plate 12 in the electronic circuit board 10 in the first embodiment. It has the metal plate 42 of a different shape, It is characterized by the above-mentioned. In the fourth embodiment, the same components as those of the insulating member 3, the solder 4, and the electronic element 5 shown in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. .

  The electronic circuit board 40 includes a metal plate 42 arranged in a direction orthogonal to the metal plate 12 in the first embodiment. The metal plate 42 includes a base portion 42a, a bent portion 42b, and a connection portion 42c.

  The base portion 42 a is a portion extending in a direction perpendicular to the longitudinal direction of the insulating member 3 in a state of being sandwiched between the upper insulating member 3 and the lower insulating member 3, and a part of the base portion 42 a is the insulating member 3. It is exposed to the opening 3h.

  The bent portion 42b is formed integrally with a part of the base portion 42a exposed to the opening 3h. The bent part 42b is a part that connects the base part 42a and the connection part 42c. The bent portion 42b includes a bent portion 42ba bent at an end portion of the base portion 42a close to the insulating member 3, a straight portion 42bs extending vertically from the bent portion 42ba toward the upper side (arrow c direction), and the straight line. A bent portion 42bc which is bent at an upper end (in the direction of arrow c) of the portion 42bs.

  The bent portion 42b is bent at two bent portions 42ba and 42bc so that the base portion 42a and the connection surface 42m of the connection portion 42c are at different height positions in the substrate vertical direction. Specifically, the bent portion 42b is a bent portion 42ba so that the connecting surface 42m of the connecting portion 42c and the exposed surface 3m of the insulating member 3 are at the same height position in the substrate vertical direction, that is, flush with each other. It is bent by 42bc.

  However, the connection surface 42m of the connection part 42c and the exposed surface 3m of the insulating member 3 do not necessarily have to be completely at the same height, and the connection surface 42m of the connection part 42c is not exposed to the surface 3m of the insulating member 3. It may be slightly recessed or slightly protruding.

  The connecting portion 42c is a portion extending linearly from the bent portion 42bc of the bent portion 42b toward the electronic element 5, and the upper surface (in the direction of the arrow c) places the electronic device 5 on the electrical and mechanical side. Thus, the connection surface 42m is connected.

  Thus, the part in which the base part 42a in the metal plate 42, the bending part 42b, and the connection part 42c are formed is formed in the cross-sectional substantially U shape. Also in this case, the bent portion 42b of the metal plate 42 falls down in the horizontal direction of the substrate, and the influence of thermal stress on the solder 4 can be absorbed.

1, 10, 10s, 20, 30, 40 Electronic circuit board 2, 12, 22, 32, 42 Metal plate 3 Insulating member 3a Surface 3h Opening 4 Solder 5 Electronic element 5a Element body 5b Electrodes 12a, 22a, 32a, 42a Base portion 12b, 32b, 42b Bent portion 12ba, 12bc Bent portion 12bs Straight portion 12c, 22c, 32c, 42c Connection portion 12d Stepped surface 12e Recessed portion 12f Through hole 12g Convex portion 12h Recessed protruding portion 2m, 12m, 22m, 32m, 42m Connection surface g Gap h Height L1 Projection amount Lmax Maximum projection amount D Opening length ep Electronic element HCS Thermal conduction sheet MM Metal mask SK Squeegee

Claims (9)

A metal plate forming a circuit conductor;
An electronic circuit board comprising an insulating member formed in a state where the metal plate is sandwiched,
The insulating member has an opening in which no insulating member exists in a part thereof,
The metal plate has a connection surface for electrically connecting one and the other base portions sandwiched between the insulating members and the electronic element in a state of being opposed to each other with the opening interposed therebetween. One and the other connecting portions exposed at the opening so that the connecting surfaces do not contact each other in a state of being opposed to each other with the opening interposed therebetween, and the height of the connecting portion is different from the base The electronic circuit board, wherein the metal plate is bent so that the first and second bent portions connect the base portion and the connecting portion, respectively. The electronic circuit board according to claim 1, wherein the connection surface is set to a height corresponding to a surface of the insulating member according to a bent state of the bent portion. The electronic circuit board according to claim 1, wherein the bent portion is not in contact with the insulating member. The electronic circuit board according to any one of claims 1 to 3, wherein the connection portion has an outflow prevention structure that prevents the solder from flowing into the bent portion on the connection surface. One electrode of the electronic device is connected to the one connection surface, the other electrode of the electronic device is connected to the other connection surface, and the one connection surface and the other connection are connected. The electronic circuit board according to any one of claims 1 to 4, wherein a surface is mechanically and electrically connected by the electronic element. The electronic circuit board according to claim 2, wherein when the insulating member is laminated with an insulating member of another electronic circuit board, the connection surfaces are connected to each other. The electronic circuit board according to claim 6, wherein the connection parts are electrically connected to each other via solder between the connection surfaces. The electronic circuit board according to claim 6, wherein the connection parts are thermally connected to each other via a heat conductive sheet between the connection surfaces. The bent portion is a portion where a part of the base of the metal plate protruding from the insulating member to the opening so as to face each other is cut and bent, and the amount of protrusion of the portion with respect to the opening is The electronic circuit board according to claim 1, wherein the electronic circuit board is not more than half of the length of the opening along the longitudinal direction of the metal plate.

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