WO2015026021A1

WO2015026021A1 - Method for additionally forming electric terminals on both side surfaces of composite power inductor

Info

Publication number: WO2015026021A1
Application number: PCT/KR2014/000308
Authority: WO
Inventors: 오세종; 오승석; 김정래
Original assignee: Oh Se Jong; Oh Seung Suk; Kim Jung Rai
Priority date: 2013-08-19
Filing date: 2014-01-10
Publication date: 2015-02-26
Also published as: KR101430427B1; TW201508788A

Abstract

Provided is a means that, in addition to two electric terminals formed at opposite ends of the bottom surface of an existing composite or power inductor, forms through a sputtering technique of electric terminals on the corresponding left and right side surfaces of the inductor which are connected to the terminals formed on the bottom surface, thereby significantly reinforcing a welding force of solder between the inductor and a circuit. Namely, a method for forming additional terminals on both side surfaces of an inductor is disclosed. The method comprises: a first step for obtaining a plurality of air-core coils (33) connected to one another, by continuing to wind an electric wire around each of a plurality of coil winding pins (31) in a coil winding plate (30); a second step for obtaining a primary shaped body (36) including a plurality of individual inductors (CI) therein, by placing the coil winding plate (30), in the state in which the air-core coils (33) are wound in the first step, in a molding machine (34') for molding the upper part of an inductor, injecting metal magnetic powder (35) into the molding machine (34'), and then making the powder subject to compression-molding; a third step for obtaining a secondary shaped body (37) having the plurality of individual inductors (CI) embedded therein, by moving the primary shaped body (36), from which the coil winding plate 30 is removed, from the molding machine in the second step to a molding machine (34") for molding the lower part of an inductor, adding the metal magnetic power (35) to the primary shaped body (36), and then making the powder subject to compression-molding; and a fourth step for simultaneously and integrally forming bottom terminals (Ta', Tb') and side terminals (Ta", Tb"), by boding masking shields (39) for terminal separation to the surface of the secondary shaped body (37) on which two bottom terminals are to be formed, depositing a metal film through a sputtering technique on elongated slits (40) formed between the masking shields in the longitudinal direction, and then detaching and removing the masking shields 39.

Description

How to Form Additional Electrical Terminals on Both Sides of Composite Power Inductors

The invention also applies to both the left and right sides of a conventional composite power inductor (hereinafter simply referred to as "inductor"), for example, in which two electrical terminals are formed only on one side (eg, bottom). A method for further forming an electrical terminal in the form of a metal thin film.

In the conventional inductor, since two coil terminals are in contact with only one surface, that is, the bottom surface, these terminal portions can be welded to the substrate by soldering when assembled to a circuit board.

Conventional methods of manufacturing inductors are described, for example, in Korean Patent Nos. 10-1044607 and 10-1044608 and March 3, 2010, Korean Patent Application No. 10-19188 by the inventors. In particular, as shown in Fig. 6 (d) in the drawings of the specification of Patent No. 10-1044608, each pair of electric terminal pieces 13 is formed on one surface of each inductor CI. In the patent application No. 10-19188, the electrical terminals Ta and Tb formed by the sputtering technique are also formed only on one surface of the inductor.

By the way, as described in each of the above patents and patent applications, the main element constituting the inductor is an iron-based magnetic metal (powder) in addition to the air core coil. Since a welding material such as solder cannot be deposited directly on the surface of the inductor except the surface on which the electrical terminal pieces are deposited (that is, the solder and the magnetic metal are not compatible), the bottom surface of the inductor In addition, it is virtually impossible to solder both sides of the circuit board with solder.

In addition, according to the manufacturing process, the inductor may be molded so that the coil terminal protrudes to the outside through a certain portion of the side of the inductor. In this case, in order for the coil terminal exposed from the side to function properly, both sides and the bottom of the inductor may be electrically connected. An integral L-shaped terminal shall be formed. This will allow solder welding to each of the side terminals, thus facilitating a more robust solder welding force of the inductor to the circuit.

Accordingly, an object or object of the present invention to solve the problem is, in addition to the bottom terminal provided on the bottom surface of the inductor, the side electrical terminals, such as metal thin film side terminals that can maintain the welding force with the solder on both the left and right sides of the inductor, the bottom surface Another object of the present invention is to provide a method of integrally forming the terminal.

The problem to be solved by the method of the present invention can be achieved by the following.

(1) a first step of continuously winding a wire around each of the plurality of coil winding pins in the coil winding plate to obtain a plurality of air core coils connected to each other; and a winding of the first process in which the air core coils are wound A second step of placing the plate in a molding machine for forming the upper part of the inductor, putting metal magnetic powder therein, and then pressing and molding to obtain a primary molded body including a plurality of individual inductors therein; and a coil from the molding machine of the second step. A third step of obtaining a secondary molded body having a plurality of individual inductors embedded therein by placing the primary molded body having the winding plate removed in a molding machine for forming the lower part of the inductor and pressing and molding by adding metal magnetic powder thereto; A masking shield for terminal isolation is attached to the surface on which the two bottom terminals of the molded body are to be formed, followed by three longitudinally extending masking shields. And a fourth step of depositing a metal thin film by sputtering to form a bottom slit and simultaneously forming a bottom terminal and a side terminal, and then peeling and removing the masking shield. A method for forming additional terminals on both sides of an inductor.

(2) In the above (1), the left and right lead wires of the hollow core coil of the buried inductor are exposed to the outside at the right and left ends of the bottom surface of the inductor or from both sides of the inductor to both sides of the composite power inductor. How to form additional terminals.

(3) The method according to the above (1) or (2), wherein the formation of the elongate slit is performed before the adhesion of the masking shield.

According to the method of the present invention, according to the protruding position of each coil lead wire of the inductor, the external electrode, i.e., the electrical terminal, is easily formed on the metal thin film, i.e., the side terminal, for example, not only on the bottom of the inductor. It can be formed integrally with each corresponding bottom terminal. Accordingly, it is possible to conveniently produce an inductor product having a uniform appearance and size [size]. Furthermore, since the strength of the terminal and the solder welding force are improved, it is possible to firmly weld the inductor to the circuit board. As a result, since the robustness and impact resistance of the electrical and electronic products are greatly increased, the failure rate of the electrical and electronic devices can be greatly reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the terminal formation surface of the molded object with which the several inductors embedded according to the previous method described in Korean Patent No. 10-1044608.

FIG. 2 is an exemplary view showing a state in which the inductor of FIG. 1 is welded in an electronic circuit with solder.

3 (a) to 3 (bar) are schematic diagrams illustrating the method of the present invention.

4 (a) to 4 (e) are schematic diagrams illustrating the principle of integrally forming electrical terminals simultaneously on both ends of the bottom of the inductor and on both sides of the inductor according to the sputtering technique.

5 is an exemplary view showing a state in which the inductor product of the present invention is welded in an electronic circuit with solder.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1A schematically shows a molded body in which a plurality of inductors CI formed by applying the molding methods described in the above-described Korean Patent Nos. 10-1044607 and 10-1044608 are embedded. 1b shows a pair of left and right electrical terminal forming portions formed on one surface of the inductor CI.

In Patent No. 10-1044608, an external electrode, that is, an external electrical terminal is formed by depositing a metal piece on a lead wire protruding portion of an air core coil, but Patent Application No. 10-19188 describes an inductor (CI) by a so-called sputtering technique. The electrical terminal is simply formed by depositing a metal thin film on a predetermined surface of the substrate. The sputtering technique is a metal thin film deposition technique already known for a long time. The technical outline thereof is well known in the art, as described in detail in the patent application No. 10-19188, according to the drawings, and thus the description thereof is omitted here. In the present invention, other conventional metal deposition methods may be used, but an electric terminal forming method using a sputtering method will be described.

1, in which the inductors (CI) molded plurality buried [in the drawing is embedded a CI of 169 (13 × 13). However, those sizes have also is variable according to the design value.] The inductor formed article code MS Marked as. The shaded portion in the figure serves as the electrical terminals 1a and 1b, which, as described above, are externally made of a separate metallic sheet at a predetermined position on one side (i.e., bottom) of the inductor CI. The terminal can be formed by welding or sputtering deposition. In Fig. 1, the portion indicated by the reference numeral EI is a portion formed between the terminal 1a and the terminal 1b, and is a region for securing electrical insulation between these two terminals. It can form by masking suitably. The shaded portions (i.e., portions 1a and 1b) in Fig. 1 are formed on the required one side of the inductor CI by a known sputtering technique (for example, gold (Au), silver (Ag), tin (Sn), copper ( Cu), nickel (Ni), etc.] is a terminal on which a thin film is deposited (deposited).

However, as described above, the present inventors have come to the idea that the welding force with the circuit can be increased if soldering can be performed not only on the two terminal portions on both ends of the bottom surface of the inductor CI, but also on both side portions. It is complete.

The characteristic and its outline | summary of this invention are shown to FIG. 3 (a)-FIG.

3 (a) and 3 (b), an automatic electric wire (wire) winding machine (not shown) around the plurality of winding pins 31 formed on the coil winding plate 30. The wires supplied by the automatic winding are automatically wound with a predetermined winding amount to form an air core coil 33. In the present invention, the diameter of the wire used is 0.05 ~ 0.15 mm, the choice depends on the size of the final inductor and there is no particular limitation. The diameter and height of the winding pin 31 also depend on the size of the final inductor, and the ratio of diameter to height is conveniently about 3: 5. Therefore, in the present invention, the winding pin 31 has a diameter of 0.3 mm and a height of 0.5 mm.

Subsequently, the winding plate 30 in the state where the air core coil 33 is wound is transferred to the inductor molding machine 34 'as it is, and a predetermined amount of magnetic metal powder 35 is introduced from the upper portion thereof, and then the molding press P The inductor upper molded body 36 is obtained by pressing under predetermined conditions to perform a molding operation. The pressing force varies depending on the specifications of the desired inductor, but may be in the range of 3 to 7 tons / cm 2. In the next step, the winding plate 30 is removed from the resultant molded inductor upper body 36 and removed. Subsequently, the upper molded body 36 is placed upside down on the lower molding machine 34 ", the same magnetic metal powder 35 is introduced from the upper part thereof, and the coil 33 is operated by operating the molding presser P under the designed conditions. The magnetic metal powder 35 is inserted into the hollow core of the core so as to be press-molded. After the molding process is finished, the final inductor molded body 37 is taken out of the molding machine 34 "and recovered.

In Fig. 3 (bar), the symbol Bs means the bottom face of the molded body 37, where the lead wire 38 of the air core coil 33 is exposed. As will be described later, the lead wire 38 may be exposed to the outside through the left and right sides of each inductor.

Fig. 4 (a) shows a plurality of hollow cores (33) connected to each other embedded therein as a result of the processes shown in Figs. The internal structure of the molded body 37 including four (16) inductors is shown schematically. Along the longitudinal arrangement of the air core coil 33 of the molded body 37, a masking shield 39 made of a synthetic resin sheet or the like is adhered on the exposed surface of the lead wire 38 in an appropriate manner. (I)]. Subsequently, an elongate slit 40 is formed between each longitudinal arrangement of the air core coils 33 (Fig. 4 (C)). A schematic diagram of the formation and structure of this slit 40 is shown in Fig. 4 (D). The adhesion process of the masking shield 39 and the formation process of the slit 40 may be different before and after, or may be performed simultaneously. Next, the molded body 37 is introduced into a sputtering apparatus (not shown, and an outline of the principle is shown in Patent Application No. 10-19188), and a metal thin film deposition process is performed by a known method. At this time, as shown in the enlarged view of FIG. 4 (D), which will be described later, the molded body 37 is placed so that the surface where the coil leads La and Lb are exposed is faced upward in the sputtering apparatus, but the manner of laying them is It depends on the structure of the sputtering apparatus. The deposited metal is selected from among suitable electrical conductor metals such as gold (Au), silver (Ag), copper (Cu), aluminum (Al), tin (Sn), nickel (Ni), etc., according to the design specification of the inductor (CI). Can be selected. In the present invention, silver (Ag) was used as the deposition metal material.

4 (d) is a cross-sectional view taken along line QQ of FIG. 4 (c), in which a terminal metal isolation zone is formed by a masking shield 39 formed on the bottom surface of an inductor CI by, for example, a silver (Ag) metal thin film. In addition to the bottom terminals Ta 'and Tb' on both left and right ends with the (EI) interposed therebetween, the surface of the slit via each slit 40, that is, the left and right sides of the five parts of each inductor CI, can function as a terminal. The state in which the thin metal [Ag] thin film, that is, the left and right side terminals Ta " and Tb ", is integrally connected to the corresponding bottom terminals Ta 'and Tb', respectively, is shown. Thereby, a pair of external terminals Ta'-Ta and Tb'-Tb "each having an" L "shape in cross section are formed integrally. In FIG. 4 (d), the left and right lead wires La and Lb of the air core coil 33 are respectively shown to be externally drawn from the bottom of the inductor CI, but are side terminals to be formed on both sides of the inductor CI. It may be exposed to the outside in place on both sides of the inductor CI so as to be in electrical connection with (Ta " and Tb" ) (not shown).

After the sputtering process, the masking shield 39 is peeled off and removed in an appropriate manner, as indicated by reference numeral 39 ' in FIG. 4 (E). Subsequently, when the molded body 37 is cut along each of the horizontal and vertical cut lines, which are also indicated by dashed lines in Fig. 4 (e), a plurality of individual inductors CI required in accordance with the pre-design standard can be easily obtained. In the example shown in Fig. 4), the number of inductors to be manufactured is 4 × 4 = 16.

The thin film thicknesses of the terminals Ta'-Tb 'and Ta "-Tb" formed integrally are several thousand micrometers to several micrometers depending on sputtering conditions, such as sputtering voltage, time, etc., and various other desired requirements. It can be adjusted to the range of, which can be easily performed by those skilled in the art. In the case of the present invention illustrated above, the thin film thickness of the terminals was measured to be on average about 2 μm.

FIG. 5 schematically shows a state where solder welding is performed when the inductor CI manufactured according to the process of the present invention described above is disposed at a predetermined position of the printed circuit B of the substrate A. FIG. . That is, the inductor CI of the present invention is not only at the site where the two bottom terminals Ta 'and Tb' are formed at both ends of the electrical insulation portion EI on the bottom thereof, but also on the left and right sides of each terminal, namely the side terminal ( Also at the site where Ta ", Tb") is formed, it becomes possible to easily form weld parts Sa and Sb by solder. Therefore, this allows the welding force to be more firm than the welding force relying only on the _two bottom terminal welding portions S ₁ and S ₂ of the existing inductor product shown in FIG. 2. In the example shown, the angular distances Ds and Dw from the upper end of the air core coil 33 to the upper surface Us and the side surface Ss of the molded body 37 are about 0.05 to 2 mm depending on the design specification of the product. The range can be varied, but the present invention is not particularly limited thereto.

Claims

A first step of continuously winding a wire around each of the plurality of coil winding pins 31 in the coil winding plate 30 to obtain a plurality of air core coils 33 connected to each other,

The winding plate 30 of the first step in the state where the air core coil 33 is wound is placed in the molding machine 34 'for forming the upper part of the inductor, and the magnetic metal powder 35 is put therein, and then pressurized and molded. A second process of obtaining a primary molded body 36 comprising a plurality of individual inductors (CI) in

The primary molded body 36 from which the coil winding plate 30 is removed from the molding machine of the second step is placed in the molding machine for molding the lower part of the inductor 34 "and the metal magnetic powder 35 is added thereto to press and mold the inside. A third step of obtaining a secondary molded body 37 with a plurality of individual inductors CI embedded in the

After attaching a masking shield 39 for terminal isolation to a surface on which two bottom terminals of the secondary molded body 37 are to be formed, an elongated slit 40 is formed longitudinally between these masking shields. A fourth thin film deposited by sputtering to form bottom terminals Ta ', Tb' and side terminals Ta ", Tb" at the same time, respectively, and then peeling and removing the masking shield 39; fair

And forming terminals on both sides of the composite inductor.
The composite inductor of claim 1, wherein the left and right lead wires of the hollow core coil 33 of the buried inductor CI are exposed to the outside at the right and left ends of the bottom surface of the inductor or at both sides of the inductor. How to form additional terminals.
Method according to one of the preceding claims, wherein the formation of the elongate slit (40) is carried out prior to the sticking of the masking shield (39).