JP5763512B2 - Electronic component, electronic device, electronic device, and manufacturing method of electronic device - Google Patents

Description

  The present invention relates to an electronic component having leads, an electronic device including the electronic component, an electronic apparatus, and a method for manufacturing the electronic device.

  In an electronic component having leads, short breaks between the leads may occur due to contact of insects or the like. For example, Japanese Unexamined Patent Application Publication No. 2009-138961 (Patent Document 1) proposes an air conditioner that can prevent a short break between leads due to the invasion of insects or the like. This air conditioner has a printed circuit board, a module mounted on the printed circuit board, and a fixed spacer capable of fixing the printed circuit board and the module. The fixed spacer has a box-shaped frame that covers the lead portion of the module. By covering the lead portion with this fixed spacer, short breaks between the leads due to contact of insects or the like can be prevented.

JP 2009-138961 A

  However, in the air conditioner described in the above publication, when a temperature change occurs inside the air conditioner, the thermal expansion coefficients of the printed circuit board, the module, and the fixed spacer are different from each other. To do. Insects, small animals, and the like enter the module lead portion from this gap, so that the insects cannot be prevented from entering the lead portion of the module. Therefore, there is a problem that when a temperature change occurs, insects or the like come into contact with the lead portion of the module, leading to component destruction due to a lead short.

  Further, there is a problem that tracking is generated in the module lead portion when moisture generated by a rapid temperature change in the air conditioner adheres to the module lead portion.

  Moreover, it is necessary to change the fixed spacer mounted between the printed circuit board and the module into an optimum shape according to each air conditioner. For this reason, there is a problem that the cost of the product and the cost of assembling process increase due to the change of the fixed spacer.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its purpose is to prevent invasion of insects and other leads into the lead, to prevent lead tracking due to moisture and the like, and to make electronic components that are low in cost and easy to assemble. An electronic device, an electronic apparatus, and a method for manufacturing the electronic device are provided.

An electronic component according to the present invention includes a circuit portion, a first resin that seals the circuit portion, a lead that is electrically connected to the circuit portion and has an end extending so as to protrude from the first resin, and a lead And a second resin having a small Young's modulus. The second resin is configured to contact and cover other than the tip portion of the end portion, and includes a convex portion for contacting the printed circuit board when mounted on the printed circuit board. When the electronic component is placed on the printed board, the electronic component is supported on the printed board by the convex portion. When the lead is flow soldered to the printed board, the second resin flows at least by the heat transmitted through the lead and reaches the printed board along the lead.

  According to the electronic component of the present invention, the second resin having a Young's modulus smaller than that of the lead is configured to contact and cover other than the tip portion of the end portion of the lead. For this reason, even if the lead expands and contracts due to a temperature change, it is possible to suppress the generation of a gap due to the second resin having a Young's modulus smaller than the lead expanding and contracting in accordance with the lead. Thereby, it is possible to prevent insects and the like from entering the lead portion from the gap.

  In addition, even if a sudden temperature change occurs, the second resin covers and touches other than the tip of the end of the lead, thus preventing moisture and the like from adhering to the tip of the end of the lead. be able to. Thereby, tracking of the lead due to moisture or the like can be prevented.

  In addition, since the second resin only needs to touch and cover other than the tip of the end of the lead, the cost can be reduced compared to the case of forming a box-shaped frame that covers the module lead. Moreover, since the second resin can be molded by resin molding, it is easy to assemble.

It is a schematic perspective view of the electronic component in Embodiment 1 of this invention. It is a circuit diagram which shows an example of the circuit part in Embodiment 1 of this invention. It is a schematic sectional drawing which follows the III-III line | wire of FIG. 1 in the state in which the electronic component in Embodiment 1 of this invention was mounted in the printed circuit board. It is a schematic sectional drawing which shows the modification 1 of the electronic component in Embodiment 1 of this invention. It is a schematic sectional drawing which shows the modification 2 of the electronic component in Embodiment 1 of this invention. It is a schematic sectional drawing which shows the modification 3 of the electronic component in Embodiment 1 of this invention. It is a schematic sectional drawing which shows the modification 4 of the electronic component in Embodiment 1 of this invention. It is a schematic exploded perspective view of the 2nd resin in Embodiment 1 of the present invention. It is a schematic sectional drawing which shows a mode that an electronic component is flow soldered to a printed circuit board in the manufacturing method of the electronic device in Embodiment 1 of this invention. In the manufacturing method of the electronic device in Embodiment 1 of this invention, it is a schematic sectional drawing which shows the state by which the electronic component was flow soldered to the printed circuit board. In the manufacturing method of the electronic device in Embodiment 1 of this invention, it is a schematic sectional drawing which shows the state by which the coating material was apply | coated to the printed circuit board. 1 is a schematic perspective view of an electronic device on which an electronic component according to Embodiment 1 of the present invention is mounted. It is a schematic perspective view of the electronic device provided with the electronic device in Embodiment 1 of this invention. It is a schematic sectional drawing at the time of the high temperature of a comparative example. It is a schematic sectional drawing at the time of the high temperature of the electronic component in Embodiment 1 of this invention. It is a schematic sectional drawing at the time of the low temperature of a comparative example. It is a schematic sectional drawing at the time of the low temperature of the electronic component in Embodiment 1 of this invention. It is a schematic perspective view of the electronic component in Embodiment 2 of this invention. It is a schematic sectional drawing in alignment with the XIX-XIX line | wire of FIG. 18 in the state in which the electronic component in Embodiment 2 of this invention was mounted in the printed circuit board. FIG. 20 is a schematic cross-sectional view of an electronic device on which an electronic component according to Embodiment 2 of the present invention is mounted, and shows a cross-section corresponding to FIG. 19. It is a schematic plan view of the electronic device with which the electronic component in Embodiment 2 of this invention was mounted. It is a schematic perspective view of the electronic component in Embodiment 3 of this invention. It is a schematic sectional drawing in alignment with the XXIII-XXIII line | wire of FIG. 22 in the state in which the electronic component in Embodiment 3 of this invention was mounted in the printed circuit board. It is a schematic sectional drawing of the electronic device with which the electronic component in Embodiment 3 of this invention was mounted, Comprising: It is a figure which shows the cross section corresponding to FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
First, the configuration of the electronic component according to Embodiment 1 of the present invention will be described.

  With reference to FIGS. 1 to 3, the electronic component 1 of the present embodiment includes a circuit portion 2, a first resin 3, a lead 4, and a second resin 5. As shown in FIG. 2, the circuit unit 2 may be a diode, for example.

  The first resin 3 seals the circuit unit 2. The lead 4 is electrically connected to the circuit unit 2. The lead 4 has an end 4 a that extends so as to protrude from the first resin 3. The second resin 5 has a Young's modulus smaller than that of the lead 4. If the Young's modulus is small, the second resin 5 is more easily deformed than the lead 4 because it is easily deformed when a force is applied to the object. That is, the second resin 5 is more flexible than the lead 4. The 2nd resin 5 is comprised so that it may contact and cover except the front-end | tip part 4b of the edge part 4a. The second resin 5 seals (molds) other than the tip end portion 4 b of the end portion 4 a of the lead 4. The second resin 5 is formed to have, for example, a cross-shaped cross section as shown in FIG.

  As the material of the second resin 5, a material having a softening point lower than the solder melting point is used. For example, in the case of a lead-free solder Sn (tin) -3.0Ag (silver) -0.5Cu (copper) composition, since the solder melting point is around 220 ° C., the resin material is melted (softened) at a temperature lower than that. . As the material of the second resin 5, for example, Atellon Telmelt 867 and Henkel OM673 are used. Alon's Telmelt 867 and Henkel's OM673 have the characteristic values shown in Table 1.

  The second resin 5 does not cover the entire lead 4, but covers the portion of the lead 4 excluding the tip portion length L to the interface between the lead 4 and the first resin 5. That is, the second resin 5 covers the lead 4 up to the end surface of the first resin 5. The tip portion length L has a relational expression of tip portion length L = first length T + second length D + third length M, and the first length T is a fillet shape after soldering. Is a length necessary for making (usually, for example, 1 mm to 4 mm). The second length D is the length of the thickness of the printed board 21. The third length M is a clearance length for avoiding blow holes during soldering.

  As shown in FIG. 3, the second resin 5 has a convex portion 5 a for contacting the printed circuit board 21 when mounted on the printed circuit board 21. When the electronic component 1 is placed on the printed circuit board 21, it can be supported on the printed circuit board 21 by the convex portions 5 a. Moreover, the 2nd resin 5 is comprised with the insulator which has thermoplasticity. The second resin 5 may be made of rubber, for example.

  In addition, the shape of the 2nd resin 5 is not limited to said shape, Various shapes can be applied. Referring to FIG. 4, the second resin 5 may be formed to have a cross-shaped cross shape that widens toward the end. Also. Referring to FIG. 5, second resin 5 may be formed to have a T-shaped cross-sectional shape. Referring to FIG. 6, second resin 5 may be formed to have a U-shaped cross-sectional shape.

  7 and 8, the second resin 5 may be configured to be attachable to the lead 4. The second resin 5 includes a first member 51, a second member 52, and a third member 53. The first member 51, the second member 52, and the third member 53 are each assembled with the lead 4, and the protrusions 55 are inserted into the holes 53, 54 so that the holes 53, 54 and the protrusions 55 are fitted. By doing so, it is configured to be fixed to the lead 4. In this case, there is no need to mold the lead 4 with the second resin 5 by injection molding.

Next, a method for manufacturing an electronic device on which the electronic component of this embodiment is mounted will be described.
Referring to FIG. 9, in the electronic device manufacturing method of the present embodiment, electronic component 1 is flow soldered to printed circuit board 21.

  First, the circuit part 2, the first resin 3 for sealing the circuit part 2, the lead 4 having the end part 4a that is electrically connected to the circuit part 2 and extends so as to protrude from the first resin 3, and the lead 4 An electronic component 1 having a smaller Young's modulus and having a second resin 5 that touches and covers other than the tip portion 4b of the end portion 4a is prepared.

  Subsequently, the lead 4 is inserted into the through hole of the printed board 21. At this time, the electronic component 1 is supported on the printed board 21 by the convex portion 5a. In this state, flow soldering (jet soldering) is performed by the molten solder 22 jetting on the lower surface side of the printed circuit board 21. The molten solder 22 is jetted from a jet solder bath (not shown). The tip portion 4 b of the end portion 4 a of the lead 4 is immersed in the molten solder 22. For example, in the case of a lead-free solder Sn (tin) -3.0Ag (silver) -0.5Cu (copper) composition, the temperature of the molten solder is set to 240 ° C. or higher and 255 ° C. or lower.

  Since there is a clearance of the third length M between the printed circuit board 21 and the second resin 5, the printed circuit board 21 absorbs moisture, and water vaporized due to a rapid temperature change in flow soldering escapes from the clearance. For this reason, the generation of blow holes and voids in the solder 23 shown in FIG. 10 is suppressed. As a result, the lead 4 is reliably bonded by the solder 23 on the upper and lower surfaces of the printed board 21, so that the quality of the solder bonding surface between the lead 4 and the printed board 21 is improved.

  Referring to FIG. 10, molten solder 22 rises from the lower surface side of printed circuit board 21 through the through hole and protrudes to the upper surface (component mounting surface) side of printed circuit board 21. In the flow soldering process, the lead 4 is heated by the molten solder 22. Since the melting temperature (softening point) of the second resin 5 is lower than the solder melting point of the molten solder 22, the second resin 5 that is in close contact with the lead 4 is melted (softened) by the heat from the molten solder 22 that is transmitted through the lead 4. ) The melted second resin 5 covers the upper surface of the lead 4 and the printed circuit board 21 around the lead 4. In the manufacturing method of the electronic device according to the present embodiment, at least the second resin 5 is caused to flow by the heat transmitted through the leads 4, and the second resin 5 reaches the upper surface of the printed circuit board 21 along the leads 4. By solidifying in this state, the second resin 5 is hardened so as to fill a gap between the printed board 21 and the first resin 3.

  A solder fillet is formed at the tip of the lead 4 on the lower surface side of the printed circuit board 21. The lead 4 is fixed to the printed circuit board 21 by the solder 23 in which the molten solder 22 attached to the lead 4 is cooled. In this way, the lead 4 is flow soldered to the printed circuit board 21.

  Referring to FIG. 11, coating material 24 is applied so as to cover the lower surface of printed circuit board 21 and solder 23. Thereafter, the coating material 24 is solidified. The electronic device 10 is manufactured by mounting the electronic component 1 as described above.

  Next, with reference to FIG. 11 and FIG. 12, the configuration of the electronic device 10 on which the electronic component 1 of the present embodiment is mounted will be described. The electronic device 10 according to the present embodiment includes the electronic component 1 according to the present embodiment, a printed circuit board 21, solder 23, a coating material 24, and other electronic components 25.

  The lead 4 of the electronic component 1 is connected to the printed circuit board 21 via the solder 23. Thereby, the electronic component 1 and the printed circuit board 21 are electrically connected. The second resin 5 of the electronic component 1 is configured to cover and cover the printed circuit board 21 and the first resin 3 except for the tip b of the end 4 a of the lead 4. The second resin 5 covers the solder 23 protruding to the upper surface side of the printed circuit board 21. The solder 23 fills the through hole of the printed circuit board 21 and protrudes also to the lower surface side of the printed circuit board 21.

  The solder 23 protruding to the lower surface side of the printed circuit board 21 is covered with a coating material 24. The pattern on the lower surface of the printed circuit board 21 and the solder 23 are protected by the coating material 24. Other electronic components 25 are also mounted on the printed circuit board 21. The other electronic component 25 is, for example, an electrolytic capacitor, a microcomputer, a relay, or the like.

  Next, with reference to FIG. 13, the configuration of the electronic device 20 including the electronic device 10 on which the electronic component 1 of the present embodiment is mounted will be described.

  The electronic device 20 according to the present embodiment includes the electronic device 10 according to the present embodiment and a main body a that is electrically connected to the electronic device 10. The electronic device 10 is configured to be able to control the main body 20a. As the electronic device 20, for example, an outdoor unit of an air conditioner, an indoor unit of an air conditioner, a water heater, or the like can be applied. For example, when the electronic device 20 is an outdoor unit of an air conditioner, the main body 20a has, for example, a compressor and a fan (not shown) in the casing.

Next, the effect of this embodiment will be described in comparison with a comparative example.
Referring to FIG. 14, in the electronic device of the comparative example, printed board 21 and heat sink 31 are fixed with screws 32. The resin spacer 33 is disposed between the printed board 21 and the heat sink 31 and is fixed to the printed board 21. Since the coefficient of thermal expansion of the resin spacer 33 is higher than that of other materials at high temperatures, stress is applied to the portion indicated by the broken line in the figure. On the other hand, referring to FIG. 15, in the electronic device of the present embodiment, second resin 5 is fixed on the lower surface of first resin 3 and the upper surface of printed circuit board 21 at a high temperature. Does not occur.

  Referring to FIG. 16, in the electronic device of the comparative example, a gap is generated in a portion indicated by a broken line in the drawing because the thermal contraction rate of resin spacer 33 is larger than that of other members at a low temperature. On the other hand, referring to FIG. 17, in the electronic device of the present embodiment, the second resin 5 is fixed on the lower surface of the first resin 3 and the upper surface of the printed circuit board 21 even at a low temperature. There are no gaps in the areas shown.

  That is, according to the electronic component 1 of the present embodiment, the second resin 5 having a Young's modulus smaller than that of the lead 4 is configured so as to contact and cover other than the tip portion 4 b of the end portion 4 a of the lead 4. For this reason, even if the lead 4 expands and contracts due to a temperature change, it is possible to suppress the generation of a gap due to the second resin 5 having a Young's modulus smaller than the lead 4 expanding and contracting in accordance with the lead 4. Thereby, it is possible to prevent insects and the like from entering the lead 4 from the gap.

  Even if a sudden temperature change occurs, the second resin 5 covers and covers the portions other than the tip portion 4b of the end portion 4a of the lead 4; Can be prevented from adhering. Thereby, tracking of the lead 4 due to moisture or the like can be prevented.

  Further, since the second resin 5 only needs to touch and cover other than the tip 4b of the end 4a of the lead 4, the material cost can be suppressed compared to the case where a box-shaped frame covering the lead of the module is formed. Therefore, low cost can be realized. In this embodiment, it is not necessary to form a frame for each module, so that low cost can be realized. In addition, when a box-shaped frame is formed, the mounting area increases. However, in this embodiment, the mounting area does not increase, so that the size can be reduced. Cost reduction can also be realized by downsizing.

  Further, since the second resin 5 can be molded by resin molding, it is easy to assemble. Moreover, since it is only necessary to mold the same shape for resin molding, low cost can be realized.

  According to the electronic component 1 of the present embodiment, since the second resin 5 includes the convex portion 5a that comes into contact with the printed circuit board 21 when mounted on the printed circuit board 21, the electronic component 1 is formed by the convex portion 5a. It can be supported on the printed circuit board 21. Since the electronic component 1 can be mounted in a state where the electronic component 1 is supported on the printed board 21 by the convex portion 5a, the electronic component 1 can be mounted accurately. Thereby, quality can be improved.

  According to the electronic component 1 of the present embodiment, since the second resin 5 is made of an insulator having thermoplasticity, the second resin 5 is caused to flow in the heating process while maintaining the insulation of the leads 4. The lead 4 can be covered.

  According to the electronic device 10 of the present embodiment, the second resin 5 of the electronic component 1 covers and covers the printed circuit board 21 and the first resin 3 except for the tip portion 4b of the end portion 4a of the lead 4. It is configured as follows. It is possible to suppress a gap from being generated between the printed board 21 and the first resin 3. Thereby, it is possible to prevent insects and the like from entering the lead 4 from the gap.

  According to the electronic device 20 of the present embodiment, the electronic device 10 is configured to be able to control the main body portion 20a electrically connected to the electronic device 10, and thus prevents the insects and the like from entering the lead. In addition, it is possible to provide the electronic device 20 that can prevent lead tracking due to moisture or the like, and can be easily assembled at low cost.

  According to the manufacturing method of the electronic device of the present embodiment, in the step of soldering the lead 4 to the printed circuit board 21, the second resin 5 is caused to flow at least by the heat transmitted through the lead 4, and the second resin 5 becomes the lead 4. Accordingly, the lead 4 can be covered with the second resin 5 using heat transmitted from the molten solder 22 during flow soldering. For this reason, it can suppress that a clearance gap produces between the 2nd resin 5 and the printed circuit board 21. FIG. Further, the lead 4 can be covered with the second resin 5 so that the lead 4 is not exposed between the second resin 5 and the printed board 21. Further, it is possible to provide a manufacturing method that is low in cost and easy to assemble.

(Embodiment 2)
Referring to FIGS. 18 and 19, in the second embodiment of the present invention, heat radiating plate 31 is attached to electronic component 1 with screws 41. The heat radiating plate 31 has a role of efficiently radiating heat to the outside when the heat generation amount of the electronic component 1 is large.

  In the present embodiment, after the heat radiation plate 31 is attached to the electronic component 1 with the screws 41, the electronic component 1 is mounted on the printed circuit board 21. When the electronic component 1 is mounted on the printed circuit board 21, the electronic component 1 can be prevented from falling due to the weight of the heat radiating plate 31 by being supported by the convex portions 5 a of the second resin 5.

  Further, by supporting by the convex portion 5a, the electronic component 1 can be kept perpendicular to the printed circuit board 21 even after the flow soldering step with reference to FIGS. Thereby, it can prevent that the heat sink 31 inclines and hits other components mounted in the printed circuit board 21. FIG. In the flow soldering process, the second resin 5 in the vicinity of the lead 4 is melted by heat, but the convex portion 5a apart from the lead 4 is not directly affected by the heat of the lead 4 and is not melted. Therefore, the electronic component 1 can be maintained perpendicular to the printed circuit board 21 by the second resin 5.

  According to the electronic component 1 of the present embodiment, it is possible to prevent the electronic component 1 from falling due to the weight of the heat sink 31, so that the electronic component 1 can be inserted perpendicularly to the printed circuit board 21. In addition, since the electronic component 1 is maintained perpendicular to the printed circuit board 21 even after the flow soldering process, the heat radiation plate 31 does not hit other components mounted on the printed circuit board 21, so that the quality can be improved. it can.

(Embodiment 3)
With reference to FIGS. 22 and 23, in Embodiment 3 of the present invention, leads 4 protrude from both side surfaces of electronic component 1. The second resin 5 is formed in contact with the side surface and the bottom surface of the first resin 3. The second resin 5 has a Y-shaped cross-sectional shape. The distance between the first resin 3 and the upper surface of the printed circuit board 21 is maintained at a length H by the convex portion 5 a of the second resin 5. The electronic component 1 can be maintained parallel to the printed circuit board 21 by the convex portion 5 a of the second resin 5.

  Referring to FIG. 24, at the time of the flow soldering process, the second resin 5 in the vicinity of the lead 4 is melted by heat, but the convex portion 5a away from the lead 4 is not melted because it is not directly affected by the heat of the lead 4. . Therefore, the electronic component 1 can be maintained parallel to the printed circuit board 21 by the second resin 5.

  Further, when it is desired to keep the distance between the electronic component 1 and the printed circuit board 21 at a constant distance, the height may be adjusted by the convex portion 5a of the second resin 5, and thus another mechanism for adjusting the height. These parts are unnecessary. Therefore, it is possible to provide the electronic component 1 that is low in cost and easy to assemble.

The above embodiments can be combined in a timely manner.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Electronic component, 2 Circuit part, 3 1st resin, 4 Lead, 4a edge part, 4b Tip part, 5 2nd resin, 5a Convex part, 10 Electronic device, 20 Electronic device, 20a Main body part, 21 Printed circuit board, 22 Molten solder, 23 solder, 24 coating material, 25 other electronic components, 31 heat sink, 32 screws, 33 resin spacer.

Claims (6)

A circuit section;
A first resin that seals the circuit portion;
A lead electrically connected to the circuit portion and having an end extending so as to protrude from the first resin;
A second resin having a Young's modulus smaller than the lead,
The second resin is configured to contact and cover other than the tip portion of the end portion, and includes a convex portion for contacting the printed circuit board when mounted on the printed circuit board.
Supported by the printed circuit board at the convex portion when placed on the printed circuit board ,
The second resin is an electronic component that flows at least by heat transmitted through the lead and reaches the printed board along the lead when the lead is flow soldered to the printed board .   The electronic component according to claim 1, wherein the electronic component is mounted in a state of being supported by the printed board by the convex portion.   The electronic component according to claim 1, wherein the second resin is formed of an insulator having thermoplasticity. A circuit section;
A first resin that seals the circuit portion;
A lead electrically connected to the circuit portion and having an end extending so as to protrude from the first resin;
An electronic component having a second resin having a Young's modulus smaller than that of the lead;
A printed circuit board to which the leads are connected,
The second resin is configured to cover and cover the printed circuit board and the first resin except for a tip portion of the end portion, and comes into contact with the printed circuit board when mounted on the printed circuit board. Including a convex portion for
The electronic component is supported on the printed board by the convex portion when placed on the printed board ,
The electronic device, wherein the second resin flows at least by heat transmitted through the lead and reaches the printed board along the lead when the lead is flow soldered to the printed board . An electronic device according to claim 4,
A main body electrically connected to the electronic device,
An electronic apparatus configured such that the electronic device can control the main body. An electronic device manufacturing method in which electronic components are flow soldered to a printed circuit board,
A circuit part; a first resin that seals the circuit part; a lead that is electrically connected to the circuit part and extends so as to protrude from the first resin; and has a Young's modulus smaller than the lead. And preparing the electronic component having a second resin that covers and covers other than the tip portion of the end portion;
And soldering the leads to the printed circuit board,
In the flow soldering step, the second resin is caused to flow at least by the heat transmitted through the lead, and the second resin reaches the printed circuit board along the lead.

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