JP4506878B2 - Coil component and method of manufacturing coil component - Google Patents

Description

  The present invention relates to a coil component used as, for example, a resonant transformer or a choke, and a method for manufacturing the coil component.

When connecting a twisted wire such as a litz wire wound around a bobbin to a pin terminal by soldering mainly in a resonant transformer for a flat-screen TV, the end of the twisted wire is entangled with the pin terminal and the end of the stranded wire is entangled. A method of forming a solder fillet by sinking the pin terminal in a solder bath is employed. Further, in Patent Document 1, the stranded wire and the pin terminal are fixed with a fine wire, and the stranded wire and the pin terminal are fixed with a fine wire so that the pin terminal having an arcuate cross section is in close contact with the peripheral surface of the tip portion of the stranded wire. And a method for connecting a pin terminal and a stranded wire by sunk them in a solder bath and soldering them.
JP-A-8-51043

  However, in the stranded wire and pin terminal connection configuration disclosed in Patent Document 1, since the end surface of the stranded wire and the tip of the pin terminal are aligned, a solder fillet is formed between the pin terminal and the stranded wire. Further, since the stranded wire is surrounded by the arc-shaped pin terminal without a gap, the penetration of the solder into the gap between the pin terminal and the stranded wire is hindered.

  An object of this invention is to provide the coil component which can perform the connection of a pin terminal and a winding | winding more reliably, and its method in view of the said problem.

The coil component according to the present invention includes a resin bobbin, a winding wound around the bobbin, a core accommodated in the bobbin, and a winding end provided on the bobbin and connected by solder. A coil component having a pin terminal, wherein the winding end extends from the bobbin along the pin terminal , and the outer peripheral surface of the pin terminal is at least one of the outer peripheral surfaces of the winding end. It has a flat or convex shape that excludes the concave surface that accepts the portion, and the tip of the pin terminal is provided so as to protrude from the end of the winding with respect to the bobbin. A wire winding portion that is bundled and fixed by the wire winding end portion, and the end surface of the winding end portion is in a position protruding from the bobbin with respect to the wire winding portion, and the end surface of the winding end portion and the pin terminal Between the peripheral surface of the wire and at least the portion protruding from the winding end. Wherein the fillet is formed.

  According to the above configuration, the solder fillet straddles between the end surface of the winding end and the peripheral surface of the pin terminal and at least the portion protruding from the winding end with respect to the bobbin. Since the contact area with the winding is formed to be wide, the end of the winding is reliably electrically connected to the pin terminal. In addition, the mechanical connection strength between the winding and the pin terminal is enhanced by the fillet. Furthermore, since the end face of the winding end protrudes from the thin wire winding portion with respect to the bobbin, the solder can easily enter the gap between the pin terminal and the winding end not tightened by the thin wire. The wire and the pin terminal are reliably electrically connected via the solder. Also, when the winding is made of a stranded wire formed by twisting a plurality of wires, it becomes easier for solder to enter from the end face of the winding end into the gap between the wires of the stranded wire not tightened by the thin wires. More reliable electrical connection and physical connection between the wire and the pin terminal.

Furthermore , the outer peripheral surface of the pin terminal has a flat or convex shape excluding a concave surface that receives at least a part of the outer peripheral surface of the winding end. With this configuration, a gap for allowing solder to enter without forming the outer peripheral surface of the pin terminal and the outer peripheral surface of the winding end in close contact is formed. Therefore, when soldering the pin terminal and the winding, the coating of the winding can be efficiently removed by the gap.

  Preferably, the thin wire is made of a conductive material. With this configuration, since the fine wire is also joined to the solder, the electrical connection between the pin terminal and the winding is more reliably performed.

  Preferably, the winding and the thin wire are made of copper wire. Since the winding and the thin wire are made of the same material and have the same thermal conductivity, the formation of solder balls is suppressed when soldering.

  Preferably, the thin wire winding portion is formed by winding the thin wire a plurality of turns at intervals. With this configuration, the turns of the adjacent thin wires are separated from each other, and solder can enter between the turns, so that the electrical connection between the pin terminal and the winding can be performed more reliably.

  Preferably, the winding end portion and the pin terminal have a substantially circular cross section in a direction perpendicular to the longitudinal direction, and the pin terminal has a smaller diameter than the winding end portion. Since the curvature of the peripheral surface of the pin terminal is increased, a large gap can be provided between the pin terminal and the end of the winding, and the coating of the winding due to the heat of the solder when soldering can be efficiently removed.

  Preferably, the end face of the winding end extends in a direction intersecting the longitudinal direction. With this configuration, the contact area between the end face of the winding end and the solder increases, so that the soldering with the pin terminal is more reliably performed.

The method of manufacturing a coil component according to the present invention includes a resin bobbin, a winding wound around the bobbin, a core accommodated in the bobbin, a protrusion protruding from the bobbin, and the winding connected by solder. have a pin terminal that is, the outer peripheral surface of the pin terminals, there at the winding end outer peripheral surface of at least a portion eliminating a concave surface to accept the plane or coil component manufacturing method from convex ing of A step of guiding the winding to a base end portion of the pin terminal and temporarily fixing the winding along the pin terminal; a step of temporarily fixing a terminal portion of the winding; Forming a thin wire winding portion for bundling and fixing the winding and the pin terminal by a thin wire on the base end side, and the winding at a position closer to the distal end side of the winding than the thin wire winding portion. Cutting the wire, and projecting the end of the pin terminal from the bobbin rather than the cut surface of the winding Characterized by a step of forming a solder fillet between the cut surface and the circumferential surface a A and the portion that protrudes from the cutting surface of at least the winding of the pin terminals of the winding.

  According to this method, the solder fillet straddles between the end surface of the winding end and the peripheral surface of the pin terminal and at least the portion protruding from the bobbin more than the winding end. Therefore, the winding end is reliably electrically connected to the pin terminal. In addition, the mechanical connection strength between the winding and the pin terminal is enhanced by the fillet. Furthermore, since it becomes easy for the solder to enter the gap between the windings not tightened by the thin wire from the cut surface of the winding to the thin wire winding portion, the winding and the pin terminal are firmly connected by the solder.

  According to the present invention, the contact area between the pin terminal of the solder fillet and the winding end can be increased, and the pin terminal and the winding are more securely electrically connected. And mechanical bond strength can be enhanced.

  Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a coil component 1 according to the present embodiment. The coil component 1 includes a bobbin 2, a winding 3 wound around the bobbin 2, and a core (not shown) made of a ferromagnetic material. The bobbin 2 is made of resin, and includes a hollow body 2A, a pair of flanges 2B, and a terminal block 2C extending from one flange 2B. A part of the core is inserted into the body portion 2A. In the terminal block 2C, a plurality of pin terminals 4 connected to the winding 3 are implanted on the side opposite to the body 2A, and a guide groove 2E for guiding the winding 3 to the pin terminal 4 is formed. Has been.

The connection between the winding 3 and the pin terminal 4 will be described with reference to FIGS. 2A and 2B. The winding 3 is made of a twisted wire (Litz wire) having a radius r ₁ in which a plurality of thin insulated wires such as enameled wires are twisted and the periphery of the twisted wires is covered with an insulating coating.

Each pin terminal 4 is obtained by molding a conductive metal into a cylindrical shape having a radius r _2, and projects are implanted into the surface 2D of the terminal block 2C. The pin terminal 4 is connected to an end 3A of the winding 3 (hereinafter referred to as a winding end 3A) in accordance with the number of windings 3 wound around the body 2A of the bobbin 2. Further, the radius r ₂ of the pin terminal 4 is smaller than the radius r ₁ of the winding 3, and the curvature of the peripheral surface is larger than that of the winding 3.

  The winding end 3A is linearly guided along the guide groove 2E of the terminal block 2C along the longitudinal direction X of the pin terminal 4, extends from the terminal block 2C, and is juxtaposed with the pin terminal 4. Further, the end surface 3B of the winding end 3A is located closer to the surface 2D of the terminal block 2C than the tip 4A of the pin terminal 4 is. The juxtaposed pin terminal 4 and the winding end 3A are fixed by a thin wire winding portion 6 that binds and fixes the vicinity of the base end portion 4B of the pin terminal 4 planted on the terminal block 2C with a thin wire 5. Yes. For example, in FIG. 2A, the thin wire winding portion 6 includes four turns of the thin wire 5 wound along the longitudinal direction X of the pin terminal 4, and the turn of the thin wire 5 closest to the end surface 3B of the winding end portion 3A. 5a is located on the base 4B side of the pin terminal 4 by a length L from the end face 3B of the winding end 3A. That is, the end face 3B of the winding end 3A protrudes from the thin wire winding part 6 by a length L with respect to the terminal block 2C. The thin wire 5 is wound so that adjacent turns are separated from each other in the longitudinal direction X. The thin wire 5 is a copper wire whose surface is not covered with an electrically insulating coating.

  Further, in order to connect the pin terminal 4 and the winding 3, a solder fillet 7 is formed so as to straddle the winding end portion 3 </ b> A and the pin terminal 4 and cover the thin wire winding portion 6. The solder fillet 7 is formed so as to come into contact with the end surface 3B of the winding end 3A and the portion 4C which is the peripheral surface of the pin terminal 4 and is located at least on the tip 4A side with respect to the end surface 3B.

  According to the coil component 1 of the present embodiment, the solder fillet 7 is formed between the end surface 3B of the winding end 3A and the peripheral surface 4C of the pin terminal 4 protruding from the terminal block 2C more than the winding end 3A. Since the contact area between the pin terminal 4 and the winding 3 is widened across the gap, the winding 3 is reliably electrically connected to the pin terminal 4. Further, the fillet 7 enhances the mechanical connection strength between the winding 3 and the pin terminal 4.

  Further, since the thin wire winding portion 6 is separated from the end face 3B of the winding end portion 3A by a length L, solder can easily enter the gap between the winding 3 and the pin terminal 4 that are not tightened by the thin wire 5. Become. In addition, as for the winding 3 itself, the portion from the end surface 3B not tightened by the thin wire 5 to the thin wire winding portion 6 has a gap between the wire rods as compared to the winding 3 positioned in the thin wire winding portion 6. Since it is widely provided, it becomes easier for solder to enter the gap between the wire rods of the winding 3 than the end face of the winding end. Accordingly, the winding 3 and the pin terminal 4 are reliably connected via the solder.

  Further, even if the pin terminal 4 and the winding end 3A are fixed so as to be juxtaposed with each other by the fine wire winding portion 6, the peripheral surface 4C of the pin terminal 4 and the peripheral surface of the winding end 3A are surfaces. Therefore, the insulating coating peeled off from the winding 3 by the heat of the solder can be efficiently removed. Further, since the winding end portion 3A is fixed by the thin wire winding portion 6 without being entangled with the pin terminal 4, the pin terminal 6 can be implanted with high density with respect to the terminal block 2C.

  Furthermore, since the thin wire 5 is made of a conductive material without an electrical insulating film, the thin wire 5 is also joined to the solder, so that the electrical connection between the pin terminal 4 and the winding 3 is more reliably performed. Further, since the surface of the copper wire is exposed, the fine wire 5 is easily wetted with the solder, so that the contact with the solder is improved.

  Further, when the conductive material of the thin wire 5 is formed of the same copper material as that of the winding 3, both the thin wire 5 and the winding 3 have the same thermal conductivity. When soldering with 3A, the formation of solder balls is suppressed.

  Further, since the thin wire winding portion 6 is composed of a plurality of turns of the thin wire 5, solder can enter between the turns of the adjacent thin wires 5 separated from each other, and the electrical connection between the pin terminal 4 and the winding 3 can be established. This can be done more reliably.

Further, the radius r ₂ of the pin terminal 4, in order than the radius r ₁ of the winding is small, it can provide increased clearance between the pin terminals 4 and the winding end portion 3A. Therefore, when soldering the pin terminal 4 and the winding 3, the coating of the winding 3 can be efficiently removed by the heat of the solder.

Furthermore, the cross-sectional shape of the pin terminal 4 is not limited to a circle, and may be a flat shape or a convex shape excluding a concave surface formed of a part of an arc having a radius r ₂ of the winding 3. Since the pin terminal 4 has such a cross-sectional shape, the cross-sectional shape of the winding 3 is usually circular, so that a gap between the pin terminal 4 and the winding 3 is widely provided and soldering is performed. It is possible to efficiently remove the covering of the winding at that time.

  Further, the thin wire 5 is not limited to copper but may be a wire made of an appropriate conductive material. Alternatively, the thin wire 5 may be a wire made of an electrically insulating material. Further, the number of turns of the thin wire 5 constituting the thin wire winding portion 6 may be one.

  Further, as shown in FIG. 3, the end face 3 </ b> B of the winding end 3 </ b> A may be formed in a direction that intersects the longitudinal direction of the winding 3, that is, obliquely. With this configuration, the area of the end face 3B increases to increase the contact area with the solder, and the area of the end face of the wire exposed from the coating of the winding 3 also increases. 4 can be reliably connected.

  In the coil component of the above embodiment, the winding 3 may be a stranded wire formed by twisting a plurality of USTC wires. Further, the winding 3 may be a single wire made of a conductive material whose surface is covered with an insulating material instead of the stranded wire.

  Next, a method for connecting the winding 3 and the pin terminal 4 will be described with reference to FIGS. 4A to 7. First, as shown in FIG. 4A, the winding 3 is used for the L-shaped pin terminal element body 4 ′ (see FIG. 4B) in which the tip portion 4A ′ is bent, and the guide portion 2E of the terminal block 2C is used. And lead. Then, the terminal portion 3C of the winding 3 is entangled with the tip portion 4A ′ and temporarily fixed, the winding 3 is arranged along the pin terminal element body 4 ′, and the base end portion of the pin terminal element body 4 ′. The winding 3 is temporarily fixed to 4B using a jig.

  Next, as shown in FIG. 5, on the base end portion 4B side of the pin terminal element body 4 ′, the winding 3 and the pin terminal element body 4 ′ are bundled so that the pin terminal element body 4 ′ is bundled by the thin wire 5. A plurality of turns are wound up along the longitudinal direction X to form a thin wire winding portion 6 for fixing the winding 3 to the pin terminal element body 4 ′. Then, as shown in FIG. 6, the pin terminal element body 4 ′ cuts off the tip end portion 4 </ b> A ′ so that the tip end of the pin terminal element body 4 ′ protrudes from the end face of the winding 3, thereby finishing the pin terminal 4. At the same time, the winding 3 leaves the portion up to the length L from the thin wire winding portion 6 and cuts the terminal portion 3C to form the winding end surface 3B, thereby forming the winding end 3A.

  Next, the pin terminal 4 and the winding end portion 3A fixed to each other by the thin wire winding portion 6 are submerged in a solder bath and soldered. By this soldering, as shown in FIG. 7, a solder fillet 7 is formed so that the solder covers the thin wire winding portion 6 and straddles the pin terminal 4 and the winding end 3A. In the solder fillet 7 formed in this manner, the solder is divided into an end surface 3B of the winding end 3A and a peripheral surface 4C which is a peripheral surface of the pin terminal 4 and protrudes at least from the end surface 3B of the winding 3. In contact. By this solder fillet 7, the pin terminal 4 and the winding end 3A are connected.

  According to the method of the present embodiment, the solder fillet 7 includes the end surface 3B of the winding end 3A and the peripheral surface 4C of the pin terminal 4 and at least a portion protruding from the bobbin from the end of the winding. Since the contact area with the pin terminal 4 and the winding 3 is widened across the gap, the winding end 3 </ b> A is reliably electrically connected to the pin terminal 4. Further, the fillet 7 enhances the mechanical connection strength between the winding 3 and the pin terminal 4. Further, since the thin wire 5 from the cut surface 3C of the winding 3 to the thin wire winding portion 6 makes it easy for solder to enter the gap between the winding end 3A and the pin terminal 4, the winding 3 and the pin terminal 4 are It is firmly connected by solder.

  In the method of the above embodiment, the tip of the pin terminal element body 4 ′ is L-shaped. However, the present invention is not limited to this, and the pin terminal element body 4 ′ may be rod-shaped. The terminal portion 3C of the winding 3 may be temporarily fixed to the tip portion 4A 'of the pin terminal element body 4' using a jig. Alternatively, in order to place the winding 3 along the pin terminal element 4 ′, the end 3C of the winding 3 is juxtaposed near the tip of the pin terminal element 4 ′ using a jig, and then the thin wire 5 May be wrapped around. Further, the thin wire winding portion 6 may be configured by one turn of the thin wire 5. Further, the winding end 3 </ b> B can be formed obliquely with respect to the longitudinal direction of the winding 3.

  Although the said embodiment demonstrated the coil component 1, the connection structure and method of a pin terminal and a coil | winding by this embodiment are the appropriate electronics which require the connection of a pin terminal and a coil | winding. Applicable to parts.

It is a perspective view which shows the bobbin and pin terminal by which the coil | winding was wound among the coil components which are this Embodiment. In the coil component which is this Embodiment, it is a perspective view which shows the connection of a coil | winding and a pin terminal. It is sectional drawing in line segment AA of FIG. 2A. In the coil component which is this Embodiment, it is a front view which shows the other connection structure of a coil | winding and a pin terminal. It is a front view explaining the temporary fixing process of a pin terminal element body and a coil among manufacturing methods of a coil component which is this embodiment. FIG. 4B is a side view of FIG. 4A. It is a front view explaining the formation process of a thin wire winding part among the manufacturing methods of the coil components which are this Embodiment. It is a front view explaining the cutting process of a pin terminal element body and a coil among manufacturing methods of a coil component which is this embodiment. It is a front view explaining the soldering process of a pin terminal and a coil end among the manufacturing methods of the coil components which are this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coil parts 2 Bobbin 3 Winding 3A Winding end part 4 Pin terminal 5 Fine wire 6 Fine wire winding part 7 Solder fillet

Claims (7)

A coil component having a resin bobbin, a winding wound around the bobbin, a core housed in the bobbin, and a pin terminal provided on the bobbin and having a winding end connected by solder Because
The winding end extends from the bobbin along the pin terminal,
The outer peripheral surface of the pin terminal has a flat or convex shape that excludes a concave surface that receives at least a part of the outer peripheral surface of the winding end,
The tip of the pin terminal is provided to protrude from the end of the winding with respect to the bobbin,
There is provided a thin wire winding part for bundling and fixing the winding end part and the pin terminal by a thin wire, and the end surface of the winding end part is located at a position protruding from the bobbin from the thin wire winding part. ,
A coil component, wherein a solder fillet is formed between an end face of the winding end portion and a peripheral surface of the pin terminal and protruding at least from the winding end portion. The coil component according to claim 1, wherein the thin wire is made of a conductive material. 2. The coil component according to claim 1, wherein the winding and the thin wire are made of copper wire. The coil component according to claim 1, wherein the thin wire winding portion is formed by winding the thin wire a plurality of turns at intervals. The winding end and the pin terminal have a substantially circular cross section in a direction orthogonal to the longitudinal direction, and the pin terminal has a smaller diameter than the winding end. Coil parts. 2. The coil component according to claim 1, wherein an end face of the winding end portion extends in a direction intersecting the longitudinal direction. A resin bobbin, a winding wound around the bobbin, a core housed in the bobbin, and a pin terminal protruding from the bobbin and connected to the winding by solder, The outer peripheral surface of the pin terminal is a method of manufacturing a coil component having a flat or convex shape excluding a concave surface that accepts at least a part of the outer peripheral surface of the end of the winding,
  Guiding the winding to the base end of the pin terminal and temporarily fixing the winding along the pin terminal;
  Temporarily fixing the end of the winding;
  Forming a thin wire winding portion that binds and fixes the winding and the pin terminal by a thin wire on the base end side of the pin terminal;
  Cutting the winding at a position closer to the end of the winding than the thin wire winding portion, and projecting the end of the pin terminal from the bobbin from the cut surface of the winding; and
  Forming a solder fillet between the cut surface of the winding and the peripheral surface of the pin terminal and protruding at least from the cut surface of the winding;
A method for manufacturing a coil component, comprising:

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