JP2011009338A - Resin sealed coil component, and manufacturing method of resin sealed coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin sealed coil component for preventing lead free solder from flowing out via a gap between an outer covering body and a lead terminal to the external part of the outer covering body, so as to excellently mount an electronic component onto a mounting substrate, and also to provide a manufacturing method of the resin sealed coil component.SOLUTION: Communication passages 40A are formed in a mold member 40. Each communication passage 40A has a columnar shape and is formed to allow the axial direction to be oriented in a direction to connect a mounting surface 40a to an opposite mounting surface 40b. One end of each communication passage 40A is opened in the opposite mounting surface 40b so as to form an opening part, and the other end of the communication passage 40A is adjacent to an internal connection line member 30. Thus, the communication passages 40A communicate the internal connection line member 30 with the external space of the mold member 40.

Description

  The present invention relates to a resin-sealed coil component and a method for manufacturing a resin-sealed coil component, and in particular, has a coil component body in which a conductor disposed in a core is electrically connected to a lead terminal via lead-free solder. The present invention relates to a resin-sealed coil component and a manufacturing method for manufacturing the resin-sealed coil component.

  2. Description of the Related Art Conventionally, a resin-sealed coil component in which a coil component body is packaged with an exterior body made of resin is known. The coil component body includes a core, a conductive wire as a conductor, and a lead terminal, and the conductive wire is wound around a part of the core. The conducting wire is electrically connected to the lead terminal by soldering, and a part of the lead terminal is exposed to the outside of the exterior body. Such a resin-sealed coil component is described, for example, in Japanese Patent Application Laid-Open No. 62-5618 (Patent Document 1).

JP 62-5618 A

  In the conventional resin-encapsulated coil component described above, the electrical connection between the lead wire and the lead terminal is soldered by using solder having a composition containing a large amount of lead. Since heavy metals such as lead have an adverse effect on the human body, so-called lead-free use in which lead is not used for components constituting the electronic device is being promoted.

  In a process of manufacturing an electronic device, a reflow method is generally used as a method for mounting an electronic component on a mounting substrate or the like. In the reflow method, the temperature of the electronic component rises to 200 ° C to 260 ° C. In the above-mentioned conventional resin-encapsulated coil components, solder having a composition containing a large amount of lead was used, so the melting point of the solder was high, and the solder did not melt even at this reflow method temperature. .

  However, in the case of a resin-sealed coil component having a coil component body in which the lead wire and the lead terminal are electrically connected via lead-free solder, the melting point of the solder is low. Lead-free solder melts. For this reason, lead-free solder has flowed out of the exterior body through the gap between the exterior body and the lead terminals, which has hindered the mounting of electronic components on the mounting board.

  Therefore, the present invention prevents the lead-free solder from flowing out of the exterior body from the gap between the exterior body and the lead terminal, and can be used to mount the electronic component on the mounting board satisfactorily. An object of the present invention is to provide a mold coil component and a method for manufacturing the resin-sealed coil component.

  In order to achieve the above object, the present invention comprises a coil component body comprising a conductor and a lead terminal forming an external electrode, the conductor being electrically connected to the lead terminal via lead-free solder, and a resin. An exterior body that sheathes the coil component main body, and the exterior body is formed with a communication path that communicates the lead-free solder and the outer space of the exterior body, or the lead-free solder and the exterior body There is provided a resin-sealed coil component in which a notch defining a space communicating with the external space is formed.

  A resin-encapsulated coil component having a coil component body in which lead-free solder made of lead-free solder is used to electrically connect the lead wire and the lead terminal is mounted on the mounting board by reflow in the reflow method. When this happens, lead-free solder flows out from the gap between the exterior body and the lead terminal to the outside of the exterior body. This is because, firstly, the melting point of lead-free solder is lower than the rising temperature of the resin-sealed coil component during reflow, so that the solder melts. Second, the temperature of the resin-sealed coil component during reflow increases Sometimes, the moisture contained in the exterior body itself is vaporized and released at the interface between the lead terminal and the exterior body, and thirdly, gas is generated from the resin itself constituting the exterior body. The inventor of the present invention has noticed that this is caused by overlapping elements.

  The exterior body is formed with a communication path that communicates the lead-free solder and the exterior space of the exterior body, or a notch that defines a space that communicates the lead-free solder and the exterior space of the exterior body. Therefore, gas or water vapor generated from the resin during reflow can be extracted outside the exterior body through the communication path or notch, and the lead-free solder is pushed out from the gap between the exterior body and the lead terminal by the gas or water vapor. The lead-free solder can be prevented from flowing out to the outer surface of the exterior body. As a result, there is provided a resin-sealed coil component having a configuration in which a conductor and a lead terminal are electrically connected by lead-free solder, and can be satisfactorily mounted on a mounting board. be able to.

  Here, the exterior body has a mounting surface facing the mounting substrate when mounted on the mounting substrate, and an anti-mounting surface positioned on the opposite side of the mounting surface, and is open to the external space. It is preferable that at least a part of the opening of the communication path or the opening of the notch that opens to the external space is disposed on the non-mounting surface.

  Since at least a part of the opening of the communication path that opens to the external space or the opening of the notch that opens to the external space is disposed on the non-mounting surface, the communication path or the notch is blocked by the flux of lead-free solder. It can be prevented from being peeled off. For this reason, the gas and water vapor | steam which generate | occur | produce from resin at the time of reflow can be reliably extracted outside an exterior body through a communicating path or a notch.

  The coil component body includes a core in which a solder receiving recess is formed, the conductor is made of a conductive wire and wound around a part of the core, and the lead-free solder is received in the solder receiving recess. preferable.

  The coil component body has a core in which a solder receiving recess is formed, the conductor is made of a conductive wire and is wound around a part of the core, and the lead-free solder is stored in the solder receiving recess, so a large amount of lead-free solder Although the lead wire and lead terminal are in an electrically connected state, the amount of lead-free solder is large because the gas and water vapor generated from the resin during reflow can be extracted outside the exterior body. The lead-free solder can be prevented from flowing out to the outer surface of the exterior body.

  The present invention also provides a step of providing a convex portion projecting inward into the cavity on a cavity defining surface that defines the cavity of the resin sealing mold in which the cavity is formed, and a conductor and an external electrode. A coil part body electrically connected to the lead terminal via a lead-free solder, with the lead-free solder in contact with the convex portion, and for sealing the resin. A resin-sealed mold having a step of setting in a cavity of a mold, and a step of filling the exterior body made of molten resin into the cavity and exteriorizing the coil component body with the exterior body A method of manufacturing a coil component is provided.

  A conductor comprising a step of forming a convex portion projecting inwardly on a cavity defining surface that defines a cavity of a resin sealing mold having a cavity formed therein, and a lead terminal forming a conductor and an external electrode And a step of setting the coil component body electrically connected to the lead terminal through the lead-free solder in a state where the lead-free solder is set in the cavity of the resin sealing mold as being in contact with the convex portion, and And the step of filling the exterior body made of molten resin into the cavity and exteriorizing the coil component body with the exterior body, so that the coil part body can be disposed at a predetermined position in the cavity, and at the time of reflow A communication path or a notch for extracting gas or water vapor generated from the resin to the outside of the exterior body can be formed in the exterior body.

  As described above, the present invention prevents the lead-free solder from flowing out of the exterior body from the gap between the exterior body and the lead terminal, and can satisfactorily mount the electronic component on the mounting board. A stationary coil component and a method for manufacturing the resin-sealed coil component can be provided.

The perspective view which shows the resin-sealed type coil components by embodiment of this invention. The bottom perspective view which shows the resin-sealed type coil components by embodiment of this invention. It is a figure which shows the resin-sealed type coil components by embodiment of this invention, (a) is sectional drawing, (b) is side perspective drawing. The schematic sectional drawing which shows the metal mold | die for resin sealing used with the manufacturing method of the resin sealing type coil components by embodiment of this invention. The perspective view which shows the modification of the resin-sealed type coil components by embodiment of this invention. Sectional drawing which shows the modification of the resin-sealed type coil components by embodiment of this invention. The perspective view which shows the other modification of the resin-sealed type coil components by embodiment of this invention. Sectional drawing which shows the other modification of the resin-sealed type coil components by embodiment of this invention.

  A resin-sealed coil component and a method for manufacturing a resin-sealed coil component according to an embodiment of the present invention will be described with reference to FIGS. First, the resin-sealed coil component 1 will be described. The resin-encapsulated coil component 1 includes a coil component main body including a coil main body 10 (electronic component), a lead terminal 20, and an internal connection member 30, and a mold member 40.

  As shown in FIG. 2, the coil body 10 includes a magnetic core 101 and a winding 102 wound around the magnetic core 101. The magnetic core 101 has a winding core portion 101c and a flange portion 101a, forming a so-called drum core. The winding core portion 101c (FIG. 3A) has a substantially cylindrical shape, and the winding 102 is wound around it. The flange portions 101a are respectively provided at both ends in the longitudinal direction of the core portion 101c, and project in a flange shape in the radial direction of the core portion 101c. A recess 101B is formed at the center of the end face of the flange 101a. The recess 101B corresponds to a solder receiving recess. In the recess 101B, lead-free solder is poured by being heated and melted in a state where a winding end portion 102a of a winding 102 described later and a part of an internal connection portion 201 of a lead terminal 20 described later are accommodated. . The poured lead-free solder is solidified to form the internal connection member 30. As shown in FIGS. 3 (a) and 3 (b), the recess 101B is formed to be greatly recessed in the flange 101a. Therefore, the internal connecting member 30 in the recess 101B is made of a resin-sealed coil component. 1 occupies a relatively large volume.

  The winding 102 is made of a conductive wire which is a copper wire with insulation coating, and the copper wire corresponds to a conductor. The winding end portion 102a passes over the two flange portions 101a and is led into the recess 101B of the flange portion 101a.

  The lead terminal 20 is configured by bending a metal plate and forms an external electrode. The lead terminal 20 has an internal connection portion 201 (first region), a mounting portion 202 (second region), and a receiving portion 204.

  The internal connection portion 201 extends from the mounting portion 202, and the tip thereof is bent so as to fit in the recess 101B. Therefore, the internal connection portion 201 is electrically connected to the winding end portion 102a via the internal connection member 30 in the recess 101B.

  The mounting portion 202 extends outward from the vicinity of both ends of the magnetic core 101 along a mounting surface 40a described later, and is bent vertically on the outer side of the mold member 40. The mounting portion 202 is a portion that is placed in contact with a mounting board (not shown). The mounting part 202 is the only part of the lead terminal 20 that is exposed to the outside of the mold member 40 described later.

  The receiving portion 204 (FIG. 2) is formed by rising from the mounting portion 202 and bending in an inverted L shape. More specifically, the receiving portion 204 is a portion that rises from the mounting portion 202 and a direction that is parallel to the axial direction of the core portion 101c from the tip of the rising portion and that the pair of lead terminals 20 approach each other. And an extending portion. The portion extending toward the flange portion 101a functions as a portion that supports the magnetic core 101 by contacting the peripheral surface of the flange portion 101a.

  The mold member 40 is made of resin, and a coil component main body including the coil main body 10, the lead terminal 20, and the internal connection member 30 is packaged to have a substantially rectangular parallelepiped shape. The mold member 40 corresponds to an exterior body. The bottom surface of the mold member 40 from which the mounting portion 202 of the lead terminal 20 is exposed has a mounting surface 40a that faces the mounting board (not shown) when the resin-sealed coil component 1 is mounted on the mounting board (not shown). Eggplant. The surface opposite to the mounting surface 40a of the mold member 40 forms an anti-mounting surface 40b.

  A communication passage 40 </ b> A is formed in the mold member 40. The communication passage 40A has a cylindrical shape as shown in FIGS. 1 and 2 and the like, and is in a direction connecting the mounting surface 40a and the anti-mounting surface 40b, that is, in the vertical direction of FIGS. 1 to 3B. It is formed so that its axial direction is directed. The upper end of the communication path 40 </ b> A is opened at the anti-mounting surface 40 b to form an opening, and the lower end of the communication path 40 </ b> A is adjacent to the internal connecting member 30. Therefore, the communication path 40 </ b> A communicates the inner connecting member 30 and the outer space of the mold member 40.

  The diameter of the communication path 40A having a cylindrical shape is about 0.1 mm, and the diameter of the communication path 40A is the width of the internal connection portion 201, the portion of the internal connection portion 201 connected to the mounting portion 202, and the mold member 40. And a small gap between them. More specifically, the width x of the internal connection portion 201 shown in FIG. 3B and the width of the minute gap between the portion of the internal connection portion 201 shown in FIG. It is determined so that the cross-sectional area of the communication passage 40A is larger than the product value of y. x is about 0.8 mm and y is about 0.003 mm. Therefore, the radius of the communication path 40A may be 0.028 mm or more, and the diameter may be 0.056 mm or more. Therefore, in this embodiment, the diameter is 0.1 mm.

  Next, a method for manufacturing the resin-sealed coil component 1 will be described. First, the coil body 10 and the lead frame are prepared. The coil body 10 is prepared in a state where the winding 102 is applied to the magnetic core 101. The lead frame is a so-called frame member having a portion that becomes the lead terminal 20 continuously. More specifically, the lead frame is formed with a portion that becomes the internal connection portion 201 and a portion that becomes the receiving portion 204. Tin plating is applied to the back surface (lower surface) of the lead frame including the surface of the mounting portion 202. The base metal of the lead frame is made of phosphor bronze, and phosphor bronze, which is the base metal, is exposed on the surface (upper surface) of the lead frame.

  Next, the coil body 10 is placed on the lead frame from above the lead frame so that the internal connection portion 201 formed on the lead frame is accommodated in the recess 101B of the flange 101. Next, lead-free solder melted by heating is poured into the recess 101B of the flange 101. In this state, the internal connection portion 201 formed on the lead frame is immersed in lead-free solder.

  Next, a step of forming the mold member 40 so as to cover the coil body 10 with a resin material is performed. More specifically, first, a resin sealing mold 1001 (FIG. 4) for molding a molten resin to be the mold member 40 is prepared. The resin sealing mold 1001 includes a fixed die 1010, a movable die 1020, and a divided die 1030 set on the movable die 1020. The divided die 1030 is set on the movable die 1020, the movable die 1020 and the divided die 1030 are brought close to the fixed die 1010, and the movable die 1020 is brought into contact with the fixed die 1010 to perform mold clamping. As a result, a cavity 1001A including a space having the same shape as the outer shape of the mold member 40 is formed inside the resin sealing mold 1001. The surfaces of the fixed die 1010, the movable die 1020, and the movable die 1020 that define the cavity 1001A form a cavity defining surface. On the surface of the divided die 1030 constituting the cavity defining surface, a pair of cylindrical convex portions 1001a are provided so as to protrude in parallel toward the inside of the cavity 1001A.

  Next, in the coil component main body including the coil main body 10, the lead terminal 20, and the internal connection member 30, the internal connection member 30 comes into contact with the convex portion 1001 a of the resin sealing mold 1001 in a state where the mold is open. The mold is clamped as a state and set in the cavity 1001A of the mold 1001 for resin sealing. At this time, since the internal connecting member 30 is in contact with the convex portion 1001a, the coil component main body can be disposed at a predetermined position in the cavity 1001A.

  Next, the mold member 40 made of molten resin is filled into the cavity 1001A and cooled. As a result, the coil component body is covered with the mold member 40. Since the projections 1001 a are provided on the split die 1030, a pair of communication paths 40 </ b> A can be formed in the mold member 40.

  Next, the lead frame is cut along a predetermined cutting line. And the resin-sealed coil component 1 is manufactured by bending the end portion of the separated lead terminal 20.

  Since the molding member 40 is formed with a communication path 40A that communicates the internal connecting member 30 and the external space of the mold member 40, gas or water vapor generated from the resin during reflow is transmitted to the molding member 40 through the communication path 40A. The lead-free solder can be pushed out from the gap between the mold member 40 and the lead terminal 20 by the gas or water vapor, and the lead-free solder can be prevented from flowing out to the outer surface of the mold member 40. As a result, the resin-sealed coil component 1 has a configuration in which the winding 102 and the lead terminal 20 are electrically connected by lead-free solder, and can be satisfactorily mounted on a mounting board (not shown). The stationary coil component 1 can be provided.

  Moreover, since the opening part of 40 A of communicating paths opened to external space is arrange | positioned in the anti-mounting surface 40b, it can prevent that 40 A of communicating paths are obstruct | occluded with the flux of lead-free solder. For this reason, the gas and water vapor | steam which generate | occur | produce from resin at the time of reflow can be reliably extracted outside the mold member 40 through the communicating path 40A.

  Further, the coil component body includes a magnetic core 101 having a recess 101B formed therein, the winding 102 is wound around the core 101c of the magnetic core 101, and the lead-free solder is accommodated in the recess 101B as the internal connecting member 30. Therefore, the winding 102 and the lead terminal 20 are electrically connected with a large amount of lead-free solder, but the gas or water vapor generated from the resin during reflow is extracted to the outside of the mold member 40. Therefore, even if the amount of lead-free solder is large, the lead-free solder can be prevented from flowing out to the outer surface of the mold member 40.

  The resin-encapsulated coil component and the method for producing the resin-encapsulated coil component of the present invention are not limited to the above-described embodiments, and various modifications and improvements can be made within the scope described in the claims. For example, in the present embodiment, the mold member 40 is formed with the communication path 40A having a cylindrical shape, but the present invention is not limited to this, and gas or water vapor generated from the resin during reflow can be extracted to the outside of the mold member. Any configuration can be used.

  For example, as shown in FIGS. 5 to 6, a part of the mold member 340 is disposed at the center position of the pair of short sides of the anti-mounting surface 340 b of the mold member 340 of the resin-sealed coil component 301 having a substantially rectangular shape. A notch 340A such as a notch may be formed. As shown in FIG. 6, the notches 340 </ b> A open to the counter-mounting surface 340 b and the end surface in the longitudinal direction of the mold member 340, respectively, and are adjacent to the internal connecting member 30. Therefore, the notch 340 </ b> A forms a space that communicates the internal connecting member 30 and the external space of the mold member 40.

  As shown in FIGS. 7 to 8, the communication path 440 </ b> A may open to an end surface 440 c in the longitudinal direction of the mold member 440 of the resin-sealed coil component 401 having a substantially rectangular parallelepiped shape.

  In addition, the resin sealing mold 1001 for molding the molten resin to be the mold member 40 includes the fixed die 1010, the movable die 1020, and the divided die 1030 set on the movable die 1020. However, the present invention is not limited to this. For example, the structure provided with a fixed die | dye, a movable die | dye, and two cylindrical pins inserted one by one in a pair of through-hole formed in the movable die | dye may be sufficient. In this case, the pin may be configured to pass through the through-hole when the mold is clamped and the tip portion of the pin protrudes into the cavity.

  The resin-sealed coil component and the method for manufacturing the resin-sealed coil component according to the present invention are, in particular, a resin-sealed coil having a coil component body in which a conductor is electrically connected to a lead terminal via lead-free solder. Particularly useful in the field of components.

1, 301, 401 Resin-sealed coil component 10 Coil body 20 Lead terminal 30 Internal connection member 40, 340, 440 Mold member 40a Mounting surface 40b Anti-mounting surface 40A Communication path 101 Magnetic core 101B Recess 102 Winding 340A Notch 1001a Convex part 1001A Cavity

Claims (4)

A coil component body comprising a conductor and a lead terminal forming an external electrode, the conductor being electrically connected to the lead terminal via lead-free solder;
An exterior body made of resin and covering the body of the coil component;
The exterior body is formed with a communication path that connects the lead-free solder and the outer space of the exterior body, or a notch that defines a space that communicates the lead-free solder and the outer space of the exterior body A resin-encapsulated coil component, wherein: The exterior body has a mounting surface facing the mounting substrate when mounted on the mounting substrate, and an anti-mounting surface located on the opposite side of the mounting surface,
The at least part of the opening of the communication path that opens to the external space or the opening of the notch that opens to the external space is disposed on the anti-mounting surface. Resin-sealed coil parts.   The coil component main body includes a core in which a solder receiving recess is formed, the conductor is formed of a conductive wire and wound around a part of the core, and the lead-free solder is received in the solder receiving recess. The resin-sealed coil component according to claim 1 or 2. Providing a cavity defining surface defining the cavity of the resin sealing mold in which the cavity is formed, and providing a convex portion protruding inward of the cavity;
A coil component body comprising a conductor and a lead terminal forming an external electrode, the conductor being electrically connected to the lead terminal via a lead-free solder, with the lead-free solder being in contact with the convex portion, A step of setting the resin sealing mold in the cavity;
A method of manufacturing a resin-encapsulated coil component, comprising: filling the cavity with a package body made of a molten resin and packaging the coil component body with the package body.

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