JPH0644112U - Chip inductor - Google Patents

Abstract

(57) [Summary] [Structure] The receiving surfaces 30, 30 located in the vicinity of the electrode plates 27, 27 made of the metal lead frames 28, 28 facing each other with a gap therebetween are provided with outer surfaces on the respective end surfaces of the flanges 24, 24. The core 22 is mounted or fitted with one end face 23a of the convex portions 34a and 34b protruding in the direction facing each other. Coil wire 26
The pull-out direction of is connected to the coil wire holding pieces 32, 32 by so-called crossing. Coil wire holding piece 3
2, 32 have at least two per electrode plate 27, 27. [Effect] The receiving surfaces 30, 30 and the coil wire holding piece 3
It is possible to simplify the shapes of the electrode plates 27, 27 including 2, 32 and the recesses 31, 31. Positioning of the core 22 and connection and fixing of the coil wires 26, 26 and the coil wire holding pieces 32, 32 can be easily and reliably performed. The electrical characteristics such as the self-inductance value and / or the Q value are improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a chip inductor, and relates to shapes of a core and an electrode plate.

[0002]

[Prior art]

 As a conventional chip inductor of this type, for example, a structure described in JP-A-62-5618 is known.

In this chip inductor, as shown in FIG. 6, a coil wire 4 is wound around a body portion of a drum-type core 3 having upper and lower flange portions 1 and 2 to form a coil 5, and a coil element 6 Are formed. Then, the lower flange portion 2 of the coil element 6 is fixed across a pair of metal plate terminals 7 and 8 facing each other, and both end portions (one is not shown) of the coil wire 4 are respectively connected to the metal plate terminals. The connection piece 9 of 7 and 8 is connected. Then, the parts other than the terminal parts 10 and 11 formed on the outer side parts of the metal plate terminals 7 and 8 are embedded in the epoxy resin 12 and are externally packaged. In the case of this conventional configuration, the magnetic line of force generated by the core is, as shown in FIG. 7, applied to a part of the metal plate terminal.

[0004]

[Problems to be solved by the device]

 However, according to the above-mentioned conventional configuration, since the recesses or the like having the same or similar shape as the core 3 must be formed in the metal plate terminals 7 and 8, the leads before punching as the metal plate terminals 7 and 8 are formed. Frame processing becomes difficult. Further, since the core 3 is likely to be displaced, it becomes difficult to solder the coil wire 4 and the connecting piece 12 of the metal plate terminals 7 and 8.

Furthermore, since there are many metal plate terminals 7 and 8 included in the range of the high magnetic field generated from the core 3 (FIG. 7), there is a problem that the electrical characteristics such as the Q value are likely to deteriorate. is doing. Here, the Q value is an amount serving as a guide for the sharpness of resonance, the goodness of selectivity, or the voltage amplification degree, and is given by Q = ωL / R. Where ω is the angular frequency, L is the self-inductance, and R is the effective resistance.

The present invention has been made in view of the above problems, and it is easy to process a lead frame, positioning the core when mounting the core on an electrode plate, soldering a coil wire and a coil wire holding piece, etc. It is an object of the present invention to provide a stable chip inductor that can be connected from both front and back sides of the coil wire holding piece, is easy and reliable, and has good electric characteristics such as Q value and is stable.

[0007]

[Means for Solving the Problems]

 The chip inductor of the present invention is a chip inductor including a drum-shaped core including a collar portion and a body portion, a coil in which a coil wire is wound around the body portion, an electrode plate, and a molded body. The inner terminal portion of the plate has at least a receiving surface portion, a coil wire holding piece, and a concave portion, and each foot of the coil wire holding piece has a coil having an outer diameter gap through which at least the coil wire can pass. There is a wire groove portion, and each end surface of the flange portion has a convex portion having a substantially circular disk shape or a substantially cylindrical shape which is convex outward, and the core has a pair of lead frames facing each other with a gap. The convex portion of one end surface of the flange portion penetrates or inserts the both concave portions across the receiving surface portion of the inner terminal portion of the electrode plate, and a part of the remaining portion of the end surface is the receiving surface portion. Mounting or mating facing each other, Note that substantially both ends of both lead wires of the coil wire are along the direction of being drawn from either the body portion or the coil wire wound around the body portion, and opposite or opposite to the respective drawing positions. At least solder connection is made to the coil wire holding piece of the electrode plate on the side.

[0008]

[Action]

 The chip inductor of the present invention is easy to process because the electrode plate made of a metal lead frame has a simple or flat shape in a flattened state. In addition, each end surface of the flange has a substantially disk-shaped convex portion that is convex outward, and has at least a receiving surface portion for mounting the coil, a coil wire holding piece, and a concave portion in the vicinity of the inner terminal portion of each electrode plate. Moreover, since the lead wire of the coil wire is connected and fixed to the coil wire holding piece on the opposite side or the opposite side along the drawing direction of the coil wire, it is possible to position the core and solder the coil and the coil wire holding piece. Connection and fixing can be done from either the core mounting side or the back side, and it can be done easily and securely. Furthermore, since the inner terminal portion of the electrode plate is not included in the high magnetic field region generated from the core, the electrical characteristics such as the Q value are good and stable.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, 21 is a chip inductor of the present invention, 22 is a drum-shaped core, and this core 22 is integrally molded with a magnetic core material such as ferrite and has end faces 23a, 23b. The disk-shaped brim portions 24, 24 are formed, respectively, and the cylindrical body portion 25 is formed between these brim portions 24, 24, which serve as a winding portion for the coil wire 26. There is.

Further, as shown in FIGS. 1 and 2, 27 and 27 are a pair of electrode plates facing each other with a gap, and these electrode plates 27 and 27 are, for example, solder-plated lead frames 28. , 28 are formed by press molding. Then, in the vicinity of the inner terminal portions 29, 29 of the electrode plates 27, 27 facing each other, receiving surface portions 30, 30 are provided, and concave portions 31, 31 are formed in a symmetrical shape. The coil wire holding pieces 32, 32 having a substantially rectangular parallelepiped shape are formed symmetrically. At the feet of the coil wire holding pieces 32, 32, there are coil wire groove portions 33, 33 formed by at least the outer diameter gap of the coil wire 26 that can pass through or wind the coil wire 26. 2 are formed for each.

Here, one shape of the recess 31 is not limited to a quadrangle, and may be, for example, a substantially semicircular shape (FIG. 3) or a substantially triangular shape (FIG. 4). Further, the coil wire holding pieces 32 and 32 may be arranged so as to be substantially rotationally symmetric in a plan view with the recesses 31 and 31 being substantially the center. Further, as shown in FIG. 4, the coil wire holding pieces 32, 32 may be erected and bent so as to have a substantially inverted L shape in cross section with respect to the surfaces of the electrode plates 27, 27. Further, the number of coil wire holding pieces 32 formed in the vicinity of one of the inner terminal portions 29 is not limited to the above-mentioned one piece (two pieces for the chip inductor 21 as a whole). 4 pieces).

Then, one of the protrusions 34a, 34b integrally formed on the end faces 23a, 23b of the flanges 24, 24 has one protrusion 34a penetrating or inserting into both the recesses 31, 31 and A part of the end surface 23a of the above is mounted or fitted so as to face the receiving surface portions 30, 30.

The coil wire 26 is made of a conductor having an electrically insulating coating made of polyurethane or the like, and is wound around the body portion 25 of the core 22 to form the coil 35. Then, one end of the coil wire 26 is drawn out from the body 25, and the coil wire of the inner terminal portion 29 on the opposite side or the opposite side along the drawing direction and at the shortest distance from the drawing position. After being wound around the holding piece 32, the insulating coating of the coil wire 26 is removed by soldering, welding, or the like, so that the coil wire 26 is electrically and mechanically connected. The other end of the coil wire 26 is pulled out from the coil wire 26 and is different from the coil wire holding piece 32, which is along the drawing direction and has the shortest distance from the drawn position. The coil wire 26 is wound around, and the insulating coating of the coil wire 26 is removed by soldering or the like, so that the coil wire 26 is electrically and mechanically connected. That is, both ends of the coil wire 26 or both of the drawing-out directions are so-called crossing directions, and the electrical insulation between them is maintained.

Reference numeral 36 denotes a molded body made of synthetic resin or the like. The molded body 36 includes a coil wire 26 forming the core 22, the coil 35, the receiving surfaces 30 and 30 of the electrode plates 27 and 27, and the coil wire. The entire holding pieces 32, 32, etc. are embedded. The outer side or outer edge of each electrode plate 27, 27 is exposed from the side surface of the molded body 36. The exposed electrode plates 27, 27 are cut from the lead frames 28, 28 with a predetermined length, and the electrode plates 27a, 27a exposed outside the mold body 36 are separated from the side faces 37, 37 of the mold body 36 and A chip inductor is manufactured by forming and bending so as to be substantially along a part of the bottom surface 38.

Further, in the present embodiment, the coil wires 26, 26 are wound around the coil wire holding pieces 32, 32 and then soldered, welded or crimped, but the coil wire holding pieces 32, 32 are not wound but wound on the coil wire holding pieces 32, 32. Alternatively, in the locked state, it can be fixed by soldering, welding, or pressure bonding.

Then, the chip inductors are mounted on the circuit board by soldering the electrode plates 27a, 27a exposed on the side surfaces 37, 37 and a part of the bottom surface 38 of the mold body 36 to a printed board (not shown). You can

The magnetic field lines in the high magnetic field region generated by the core 22 when mounted on the electrode plates 27, 27 having the mold body 36, the coil 35 and the like of the present invention configured as described above are shown in FIG. Shown in. From FIG. 5, since the magnetic lines of force are not applied to the electrode plates 27, 27, etc., the electrical characteristics such as the Q value can be made good and stable.

[0019]

[Effect of device]

 According to the present invention, the shape of the electrode plate formed of the metal lead frame in a flattened state is simple or simple, which facilitates processing. In addition, each end surface of the collar portion has a substantially disk-shaped convex portion that is convex outward, and has at least a receiving surface portion for mounting a coil, a coil wire holding piece, and a concave portion in the vicinity of the inner terminal portion of each electrode plate, Moreover, since the lead wire of the coil wire is connected and fixed to the coil wire holding piece on the opposite side or the opposite side in the drawing direction of the coil wire, the core is positioned and the coil and the coil wire holding piece are soldered, welded, or crimped. It is possible to fix the connection with either the core mounting side or the back side, and it can be done easily and surely, and the fine adjustment of the self-inductance value can be improved with high accuracy. Further, since the inner terminal portion of the electrode plate is not included in the high magnetic field region generated from the core, the electric characteristics such as self-inductance or Q value are good and stable.

[Brief description of drawings]

FIG. 1 is a perspective view of a chip inductor according to an embodiment of the present invention with a molded body omitted.

FIG. 2 is a plan view of the same lead frame and electrode plate.

FIG. 3 is a perspective view of the same electrode plate in which one of the concave portions has a substantially semicircular shape.

FIG. 4 is a perspective view of the same electrode plate in which one of the concave portions has a substantially triangular shape.

FIG. 5 is a partially omitted vertical sectional view showing magnetic lines of force when a core is mounted on the electrode plate of the present invention.

FIG. 6 is a perspective view showing a conventional chip inductor with a molded body omitted.

[Explanation of symbols]

 21. Chip inductor 22. Core 23a, 23b End surface 24. Tsubabe 25. Body 26. Coil wire 27, 27a Electrode plate 28. Lead frame 29. Inner terminal part 30. Receiving surface 31. Recess 32. Coil wire holding piece 33. Coil wire groove portions 34a, 34b Convex portion 35. Coil 36. Molded body 37. Side 38. Bottom

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[Procedure amendment]

[Submission date] November 8, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 7

[Correction method] Added

[Correction content]

FIG. 7 is a partially omitted vertical cross-sectional view showing magnetic lines of force when a core is mounted on a metal plate terminal in a conventional chip inductor.

Claims (1)

[Scope of utility model registration request] 1. A drum-shaped core comprising a collar portion and a body portion,
In a chip inductor including a coil in which a coil wire is wound around the body, an electrode plate, and a molded body, an inner terminal portion of the electrode plate has at least a receiving surface portion, a coil wire holding piece, and a recess. However, each foot of the coil wire holding piece has a coil wire groove portion having an outer diameter gap through which at least the coil wire can pass, and each end surface of the collar portion has a substantially circular plate or a substantially circular cylinder convex outward. A protrusion having a shape, the core straddles between the receiving surface portions of the inner terminal portions of the pair of electrode plates formed of lead frames facing each other with a gap, and one of the flange portions is provided. The convex portion of the end surface penetrates or inserts both the concave portions, a part of the remaining portion of the end surface is mounted or fitted so as to face the receiving surface portion, and substantially both ends of both lead wires of the coil wire are On the body and on the body At least a solder connection is made to the coil wire holding piece of the electrode plate on the opposite side or opposite side of each drawn position along the direction drawn from any one of the wound coil wires. Inductor.