JP2009027043A - Electronic component and its assembling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component which reduces thermal resistance generated between the electronic component and an external heat radiating material, and is excellent in heat radiating property. <P>SOLUTION: The electronic component 1 includes a main body 2 having a lead terminal 3, and a metal radiating terminal 4 integrally, and the external heat radiating material 6 is fixed to the heat radiating terminal 4. The heat radiating terminal 4 and the external heat radiating terminal 6 are soldered by which the uneven surface of the heat radiating terminal 4 is filled with solder, the thermal resistance generated between the heat radiating terminal 4 and the external heat radiating material 6 can be reduced, and the heat radiating property of the electronic component 1 can be secured. Moreover, an energization property between the heat radiating terminal 4 and the external heat radiating material 6 is also improved. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic component in which a component-side heat radiating portion is fixed to an external heat radiating body such as a heat radiating plate, and an assembling method thereof.

  2. Description of the Related Art Conventionally, various electric devices represented by switching power supply devices have electronic components that are heating elements such as semiconductor elements, and heat generated from the electronic components is prevented in order to prevent a significant temperature rise of such electronic components. Is provided to a heat receiving plate in contact with the electronic component, and radiated from a heat radiating portion such as a heat radiating pin or a heat radiating fin, thereby providing a radiator that reduces the temperature rise of the electronic component. (For example, Patent Document 1, Patent Document 2, and Patent Document 3).

  As shown in FIG. 8, an electronic component 101 such as a semiconductor element integrally includes a main body 102 having a plurality of lead terminals 103 and a heat radiating terminal 104 that is a component-side heat radiating portion. Further, the lead terminal 103 is inserted into the through hole 106 of the printed wiring board 105 and soldered and mounted by the soldering portion 107, and the component side heat radiating portion 104 is externally radiated from a copper plate having excellent thermal conductivity. A heat sink 109 having a plurality of fins is disposed on the other side of the external heat sink 108 along one side of the body 108, and the external heat sink 108 and the heat sink 109 are fixed to the electronic component 101 with screws 110.

  Thereby, the heat generated in the electronic component 101 is transmitted to the external heat radiating body 108 and radiated by the heat sink 109. In addition, when using the component side heat radiation part 104 as a heat radiation terminal, the heat sink 109 is electrically connected to the printed wiring board 105.

  Further, as shown in FIG. 9, the lead terminal 103 is soldered to the conductive pattern 112 on one side of the metal substrate 111 by the soldering portion 113, and the heat radiating terminal 103 is soldered to the conductive pattern 112 by the soldering portion 113. To be implemented.

A heat sink 114 is provided on the other side surface of the metal substrate 111, and heat generated in the electronic component 101 is transmitted to the external heat radiator 108 and is radiated by the heat sink 114.
JP 2005-175225 A JP 2006-310552 A JP 2006-339341 A

  In the mounting structure shown in FIG. 8, since the outer surface of the heat radiating terminal 104 is not a perfect plane but an uneven surface, it is not in surface contact with the external heat radiating body 108, but is in point contact, so that thermal resistance is thermally increased. When the heat dissipation terminal 104 is used as a terminal, if the current capacity is insufficient, an auxiliary bus bar or the like is required and the cost increases. is there.

  On the other hand, in the mounting structure shown in FIG. 9, since the heat radiating terminal 104 and the lead terminal 103 are connected to the conductive pattern by soldering, the thermal resistance is reduced and the heat of the electronic component 101 is transmitted to the metal substrate 111 side. It becomes easy.

  However, since current flows only through the conductive pattern 112, the electrical resistance increases, and when the conductive pattern 112 alone is insufficient, an auxiliary bus bar or the like is required, resulting in an increase in cost. The printed wiring board 105 costs more.

  The present invention has been made paying attention to each of the above problems, and can provide an electronic component that can reduce the thermal resistance between the electronic component and the external heat radiating body and has excellent heat dissipation, and an assembling method thereof. And its purpose.

  In order to achieve the above object, the present invention provides an electronic component comprising a main body having a terminal and a metal component-side heat radiating portion, and the component-side heat radiating portion fixed to an external heat radiating body. And the external heat radiator are soldered.

  Moreover, in order to achieve the above-mentioned object, the present invention is one in which the surface of the component-side heat radiating portion and the surface of the external heat radiating body are combined and soldered.

  Furthermore, in the present invention, in order to achieve the above object, the external radiator has a heat sink.

  Furthermore, in the present invention, in order to achieve the above object, the terminal is connected to a bus bar.

  In order to achieve the above object, the present invention provides an electronic component assembling method in which the component side heat dissipating part is soldered to the external heat dissipating member and the terminal is soldered to a bus bar. The bus bar is disposed on the mounting portion, cream solder is applied to the external heat radiating body and the bus bar, the component-side heat radiating portion is aligned with the external heat radiating member, the terminal is aligned with the bus bar, and the electronic component is moved forward. It is an assembling method which arrange | positions to a description part and heats and solders the said cream solder.

  Furthermore, in order to achieve the above object, the present invention provides that the mounting portion is a transport board, and the transport board is provided with positioning portions for the external radiator and the bus bar, respectively, and the positioning portion for the electronic component. Is an assembly method.

  According to the invention of claim 1, by soldering the component-side heat dissipation portion and the external heat dissipation body, the uneven surface of the component-side heat dissipation portion is filled with solder, and between the component-side heat dissipation portion and the external heat dissipation body. Thermal resistance can be reduced, and heat dissipation of electronic components can be ensured.

  According to the second aspect of the present invention, the uneven surface can be filled with solder so that the component-side heat radiation portion and the external heat radiation body can be brought into contact with each other over a wide area.

  According to invention of Claim 3, heat dissipation can be improved with a heat sink.

  According to the invention of claim 4, it is possible to secure the energization amount on the terminal side.

  According to the invention of claim 5, the soldering process to the external heat radiating body and the bus bar can be efficiently performed, and the assembling workability is improved.

  According to invention of Claim 6, an external heat radiator and a bus-bar can be positioned with respect to a conveyance board, and automation of a soldering operation | work can be performed easily.

  Preferred embodiments of an electronic component and an assembling method thereof according to the present invention will be described below in detail with reference to the accompanying drawings.

  1 to 5 show an electronic component proposed in this embodiment and an assembling method thereof. As shown in FIG. 1, reference numeral 1 denotes an electronic component such as a semiconductor element. A plurality of lead terminals 3 are arranged in parallel at the lower portion of the main body 2 serving as a heat source, and a component-side heat dissipation portion is provided on one side of the main body 2. The heat radiating terminal 4 is integrally provided, and the heat radiating terminal 4 has a substantially flat plate shape. The main body 2 is molded with resin, and the heat generated in the main body 2 is transmitted to the heat radiating terminal 4 and radiated to the outside. The lead terminal 3 projects downward from the main body 2, and the leading end side of the lead terminal 3 faces one side of the main body 2.

  Reference numeral 5 denotes a printed wiring board on which various electronic components of the power supply device including the electronic component 1 are mounted on one side or both sides. For example, a desired conductive pattern is formed on one side or both sides of an insulating material such as glass epoxy.

  The side surface 4A of the heat radiating terminal 4 is along the other side surface 6A of the external heat radiating body 6, and the external heat radiating body 6 is made of a copper plate having excellent thermal conductivity. Is fixed by a soldering portion 7. In this case, even if one side surface 4A of the heat radiating terminal 4 is an uneven surface, by melting the solder material along the end surface 4B intersecting the other side surface 6A of the external heat radiating body 6 of the heat radiating terminal 4, The molten solder enters between the one side surface 4A and the other side surface 6A, fills the gap between the one side surface 4A and the other side surface 6A, and the one side surface 4A and the other side surface 6A are in surface contact with each other over a wide area. That is, the gap between the one side surface 4A and the other side surface 6A generated in the butted state is filled with the soldering portion 7.

  A heat sink 8 is in surface contact with one side surface of the external heat radiating body 6, and a plurality of heat radiating fins 9 are provided on one side of the heat sink 8. The heat sink 8 is fixed to the external heat radiator 6 by appropriate means. In this case, the heat radiating terminal 4, the external heat radiating body 6, and the heat sink 8 may be fixed by screws (not shown), or the heat radiating terminal 4 and the external heat radiating body 6 are fixed by the soldering portion 7. Therefore, the external radiator 6 and the heat sink 8 may be fixed.

  The leading end of the lead terminal 3 is fixed to the other side surface 11 </ b> A of the bus bar 11 by a soldering portion 10. The bus bar 11 is made of a conductive metal flat plate or the like, and has a substantially L shape in which the side to which the lead terminal 3 is connected is narrowed. The other side surface 11A of the bus bar 11 and the other side surface 6A of the external heat radiating body 6 are substantially parallel. In this example, the other side surface 11A and the other side surface 6A are located on substantially the same plane.

  The bus bar 11 is fixed to the printed wiring board 5 and is electrically connected to the conductive pattern of the printed wiring board 5, whereby the electronic component 1 is mounted on the printed wiring board 5. Further, the heat sink 8 is electrically connected to the printed wiring board 5 as necessary.

  Next, an example of a method for assembling the electronic component 1 will be described. A reflow soldering device is used for soldering the electronic component 1 to the external radiator 6 and the bus bar 11. In this reflow soldering apparatus, the electronic component 1, the external radiator 6 and the bus bar 11 are placed on a carrying board 21 which is a placing portion, and the carrying board 21 is carried by driving means such as an endless chain. In the meantime, the solder is gradually melted by heating means (not shown) to perform soldering. The transport board 21 is made of a magnesium alloy or the like.

  As shown in FIGS. 3 and 4, the external heat dissipating body 6 has a shape that allows connection of heat dissipating terminals 4 of a plurality (two in the figure) of the electronic component 1. On the upper surface of the transport board 21, there are provided a positioning recess 22 which is a positioning portion of the external radiator 6 and a positioning recess 23 which is a positioning portion of the bus bar 11. The positioning recess 23 of the bus bar 11 is the number of the bus bars 11. It is provided corresponding to. Then, the external heat radiator 6 is detachably fitted in the positioning recess 22 and positioned, and the bus bar 11 is detachably fitted and positioned in the positioning recess 23.

  The positioning recesses 22, 23, 23 are formed in the transport board 21 corresponding to the electronic components 1, 1, and are positioned between the positioning recesses 22, 23, and the transport board 21 includes A protrusion 24 is provided as a positioning portion for positioning the electronic component 1, and the positioning protrusion 24 is disposed at a position sandwiching the main body 2 of the electronic component 1 from the left and right.

  Then, the external radiator 6 and the bus bars 11 and 11 are arranged in the positioning recesses 22, 23 and 23 by a transfer means (not shown) such as a robot hand, and thereafter, by an application means (not shown). The cream solder 25 is printed on the upper surfaces of the external heat radiator 6 and the bus bars 11 and 11 in the positioned state. In this case, the cream solder 25 is printed and applied to the bus bar 11 corresponding to the connection positions of the lead terminals 3 and 3, and the other side surface corresponding to the butted portion between the one side surface 4A and the other side surface 6A. The cream solder 25 is printed on the other side surface 6A in the vicinity of 6A and the end surface 4B. In FIG. 3, six cream solders 25 are printed on the other side surface 6A corresponding to the abutting location, and three cream solders 25 are printed on the other side surface 6A in the vicinity of the end surface 4B. After the cream solder 25 is printed, the electronic components 1 and 1 are placed on the transfer board 21 by the transfer means. In this case, the electronic component 1 is placed and set at a position between the protrusions 24 and 24.

  Thereafter, while the transport board 21 is transported, the cream solder 25 is gradually melted by a heating means (not shown), and the melted cream solder 25 is solidified to form the soldered portions 7 and 10. After the assembly, the electronic components 1 and 1 are removed from the transport board 21 and mounted on the printed wiring board 5.

  In the electronic component 1 configured as described above, even if the one side surface 4A of the heat radiating terminal 4 is uneven, solder enters the gap between the one side surface 4A of the heat radiating terminal 4 and the other side surface 6A of the external heat radiating body 6, The one side surface 4A and the other side surface 6A can be brought into close contact with each other, and the heat generated in the main body 2 can be efficiently radiated from the heat sink 8 through the external heat radiating body 6. When the heat sink 8 is electrically connected to the conductive pattern and the heat radiating terminal 4 is electrically connected to the printed wiring board 5 via the external heat radiating body 6 and the heat sink 8, the heat radiating terminal 4 and the external heat radiating are provided. A current-carrying capacity between the body 6 and the body 6 can be ensured.

  As described above, in this embodiment, the electronic component 1 including the main body 2 having the lead terminals 3 serving as the terminals and the heat radiating terminals 4 serving as the metal component-side heat radiating portions, and the heat radiating terminals 4 fixed to the external heat radiating body 6. In this case, since the heat radiating terminal 4 and the external heat radiating body 6 are soldered, the uneven surface of the heat radiating terminal 4 is filled with the soldering portion 7 to reduce the thermal resistance between the heat radiating terminal 4 and the external heat radiating body 6. The heat dissipation of the electronic component 1 can be ensured. Further, when the heat radiating terminal 4 is electrically connected to the printed wiring board 5, a current-carrying capacity between the heat radiating terminal 4 and the external heat radiating body 6 can be ensured by the surface contact state.

  Further, since one side surface 4A of the heat radiating terminal 4 which is the component side heat radiating portion and the other side surface 6A of the external heat radiating body 6 are combined and soldered, one side surface 4A forming the unevenness of the heat radiating terminal 4 is filled with solder. And the external radiator 6 can be brought into contact with each other over a wide area.

  Moreover, since the external heat radiator 6 has the heat sink 8, heat dissipation can be improved.

  Moreover, since the lead terminal 3 which is a terminal is connected to the bus bar 11, it is possible to secure an energization amount on the lead terminal 3 side.

  As described above, in the present embodiment, in the method of assembling an electronic component in which the heat radiating terminal 4 serving as the component side heat radiating portion is soldered to the external heat radiating body 6 and the lead terminal 3 serving as the terminal is soldered to the bus bar 11, 6 and the bus bar 11 are arranged on the transfer board 21 serving as a mounting portion, and the solder paste 25 is applied to the external heat radiating body 6 and the bus bar 11 so that the heat radiating terminal 4 is aligned with the external heat radiating body 6 and the lead terminal 3 is connected to the bus bar 11. In addition, since the electronic component 1 is placed on the transfer board 21 and the cream solder 25 is heated and soldered, the soldering to the external heat radiating body 6 and the bus bar 11 can be performed efficiently, and the assembly is performed. It can be done easily.

  Further, the mounting portion is the transport board 21, and the transport board 21 is provided with the positions 22 and 23 that are the positioning portions of the external radiator 6 and the bus bar 11, and the protrusion 24 that is the positioning portion of the electronic component 1. Therefore, the external heat radiator 6 and the bus bar 11 can be positioned with respect to the transport board 21, and the soldering operation while transporting can be easily performed.

  FIG. 6 shows a second embodiment of the present invention. The same reference numerals are given to the same portions as those of the first embodiment, and detailed description thereof will be omitted. In this example, the through wiring of the printed wiring board 5 is shown in FIG. The lead terminal 3 is inserted into the hole 12, and the electronic component 1 is mounted on the printed wiring board 5 by the soldering portion 13. In this case, it can solder by the said conveyance board 21 without the said positioning recessed part 23. FIG.

  As described above, in this embodiment, in the electronic component in which the main body 2 having the lead terminal 3 as the terminal and the heat radiating terminal 4 as the metal component side heat radiating portion are integrally provided and the heat radiating terminal 4 is fixed to the external heat radiating body 6. Since the heat radiating terminal 4 and the external heat radiating body 6 are soldered, the uneven surface of the heat radiating terminal 4 is filled with the soldering portion 7 to reduce the thermal resistance between the heat radiating terminal 4 and the external heat radiating body 6. The heat dissipation of the electronic component 1 can be ensured, and the lead terminals 3 may be electrically connected to the printed wiring board 5 and mounted as in this example.

  FIG. 7 shows a third embodiment of the present invention. The same reference numerals are given to the same portions as those of the above-described embodiments, and detailed description thereof will be omitted. In this example, the heat sink 8 as an external radiator is illustrated. The other side surface and one side surface 4 </ b> A of the radiating terminal 4 are combined and soldered by the soldering portion 7.

As described above, in this embodiment, the main body 2 having the lead terminal 3 as the terminal and the heat radiating terminal 4 as the metal component side heat radiating portion are integrally provided, and the heat radiating terminal 4 is fixed to the heat sink 8 as the external heat radiating body. In the component, since the heat radiating terminal 4 and the heat sink 8 are soldered, the uneven surface of the heat radiating terminal 4 is filled with the soldering portion 7, and the thermal resistance between the heat radiating terminal 4 and the heat sink 8 can be reduced. The heat dissipation of the electronic component 1 can be secured,
In addition, this invention is not limited to the said Example, A various deformation | transformation implementation is possible in the range of the summary of this invention. For example, in the embodiment, the external heat radiating body and the bus bar are positioned on the mounting portion by the recessed positioning portion, but the positioning portion may be configured by protrusions surrounding the external heat radiating body and the bus bar.

It is sectional drawing in Example 1 of this invention. It is a perspective view of a conveyance board same as the above. It is a top view of the conveyance board of the state which applied the cream solder same as the above. It is a top view of the state which has arrange | positioned an electronic component to a conveyance board same as the above. FIG. 5 is a sectional view taken along line AA in FIG. It is sectional drawing in Example 2 of this invention. It is sectional drawing in Example 3 of this invention. It is sectional drawing which shows a prior art example. It is sectional drawing which shows another prior art example.

Explanation of symbols

1 Electronic component 2 Body 3 Lead terminal 4 Heat dissipation terminal (component side heat dissipation part)
5 Printed wiring board 6 External heat sink 7 Soldering part 8 Heat sink (external heat sink)
10 Soldering part 11 Bus bar 21 Transfer board (mounting part)
22 Positioning recess (Positioning part of external radiator)
23 Positioning recess (Busbar positioning part)
24 Protrusion (Electronic component positioning part)
25 Cream solder

Claims (6)

In an electronic component that is integrally provided with a main body having a terminal and a metal component side heat radiating portion, and the component side heat radiating portion is fixed to an external heat radiating member, the component side heat radiating portion and the external heat radiating member are soldered. Electronic parts characterized by 2. The electronic component according to claim 1, wherein a surface of the component-side heat radiating portion and a surface of the external heat radiating body are aligned and soldered. The electronic component according to claim 1, wherein the external heat radiator has a heat sink. The electronic component according to claim 1, wherein the terminal is connected to a bus bar. In the method of assembling an electronic component in which the component side heat dissipating part is soldered to the external heat dissipating member and the terminals are soldered to the bus bar, the external heat dissipating member and the bus bar are disposed on the mounting part, and the external heat dissipating members are disposed. The solder paste is applied to the bus bar, the component side heat dissipating part is aligned with the external heat dissipating member, the terminal is aligned with the bus bar, the electronic component is disposed on the mounting part, and the cream solder is heated. The method of assembling an electronic component according to claim 1, wherein soldering is performed. 6. The electronic device according to claim 5, wherein the placement unit is a transport board, and the transport board is provided with a positioning unit for the external radiator and the bus bar, and a positioning unit for the electronic component. How to assemble parts.

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