JPH0817652A - Laminated coil - Google Patents

Abstract

PURPOSE:To provide the title laminated coil capable of eliminating a terminal base as well as securing a sufficient mechanical strength when packaged on a printed substrate, etc. CONSTITUTION:Coil conductors 18 are formed on the surface of insulating sheets 14. The ends 20 of these coil conductors 18 and a plurality of reinforcement dummy conductors 21 not connected to the coil conductors 18 are protruded from the edge part of the sheets 14. The sheets 14 are laminated to constitute the coil part. The ends 20 and the reinforcement dummy conductors 21 in the laminated state protrude from the side of the coil part. In such a constitution, the laminated ends 20 and the reinforcement dummy conductors 21 are electrically connected by means of spot welding step, etc., to be integrated into leading-out electrodes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated coil, and more particularly to a laminated coil such as a transformer or a filter mounted on a printed circuit board or the like.

[0002]

2. Description of the Related Art In general, a laminated coil is an electrical connection in which an insulating sheet having a conductor for a coil formed on the surface is laminated to form a coil portion, and conductors for each coil are provided on the insulating sheet. It is connected through means. In this laminated coil, it is conceivable that the end portion of the coil conductor is projected from the edge portion of each insulator sheet to form a lead electrode.

However, since the extraction electrode has a weak mechanical strength, it cannot be directly mounted on a printed circuit board or the like, and a separate terminal block is prepared and spot welding or soldering is performed on the terminal block. After electrically connecting the extraction electrodes, it is necessary to mount the laminated coil on a printed circuit board or the like with terminals provided on the terminal block. Therefore, the cost of the terminal block and the step of assembling the coil portion to the terminal block are required, and the manufacturing cost of the obtained laminated coil increases accordingly.

Therefore, an object of the present invention is to provide a laminated coil which does not require a terminal block and can secure sufficient mechanical strength when mounted on a printed circuit board or the like.

[0005]

In order to solve the above problems, in the laminated coil according to the present invention, an end portion of the coil conductor protruding from an edge portion of each insulator sheet and the coil conductor are provided. It is characterized in that a lead-out electrode is formed by stacking a reinforcing dummy conductor which is not connected to. With the above configuration, since the end portion of the coil conductor is overlapped with the reinforcing dummy conductor, the mechanical strength of the extraction electrode is increased,
The laminated coil is mounted on a printed circuit board or the like with sufficient mechanical strength without using the terminals provided on the terminal block.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the laminated coil according to the present invention will be described below with reference to the accompanying drawings. The following examples describe laminated coils used as transformers. As shown in FIG. 1, the laminated coil 1 includes a coil portion 10 and magnetic cores 40 and 45. Coil part 10
Is a laminate of a plurality of insulator sheets 14 including the insulator sheet 14 illustrated in FIGS. 2 and 3. At the center of the insulating sheet 14 shown in FIG. 2 and FIG.
A hole 16 for inserting 0 is provided.

On the sheet 14, a spiral coil conductor 18 is formed around the hole 16. Sheet 14
For this, an insulating material such as a polyimide substrate is used. Further, the end portion 20 of the coil conductor 18 and a plurality of reinforcing dummy conductors 21 that are not connected to the coil conductor 18 project from the edge of the sheet 14. The end portion 20 and the reinforcing dummy conductor 21 are tapered. here,
The reinforcing dummy conductors 21 do not need to be provided on the left and right sides of the sheet 14, and may be provided only on the side where the end portion 20 of the coil conductor 18 projects. When these sheets 14 are stacked, the coil conductor 18 is electrically connected via the via hole 28 to form an inductor.

A hole 10a constituted by a hole 16 formed in each sheet 14 is provided at the center of the coil portion 10 formed by laminating the insulating sheets 14. The end portion 20 and the reinforcing dummy conductor 21 overlap each other in the coil portion 10
Protruding from the side. The overlapping end portion 20 and the reinforcing dummy conductor 21 are electrically connected by means such as spot welding or soldering, and after being integrated,
It is bent to form the extraction electrode 22.

Only one inductor may be formed in the coil portion 10 or a plurality of inductors may be formed and used as a transformer or the like. In addition, a plurality of inductors can be connected in series or in parallel by changing the connection method of the coil conductor 18 provided on each insulator sheet 14.

Further, a core 40 having an E-shaped cross section and a cross section I
The letter-shaped core 45 is attached. The core 40 has a middle leg portion 42 at the center and outer leg portions 44a and 44b at both ends. The middle leg portion 42 is inserted into the hole 10 a of the coil portion 10. The cores 40 and 45 are fixed to each other with an insulating tape 47 or the like as shown in FIG.

The laminated coil 1 having the above configuration is mounted on, for example, a printed circuit board or the like. At this time, the extraction electrode 22 and the pattern electrode of the printed board are connected by soldering or the like. Here, the function and effect of the extraction electrode 22 when the laminated coil 1 is mounted on a printed circuit board or the like will be described. The extraction electrode 22 is the end 2 of the coil conductor 18.
Since it consists of 0 and the reinforcing dummy conductor 21, it has a high mechanical strength. Therefore, the laminated coil 1 can be mounted on a printed circuit board or the like with sufficient mechanical strength without using the terminal block used in the conventional laminated coil. Further, the height of the laminated coil 1 is reduced because the terminal block is omitted.

The laminated coil according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the gist thereof. The shape of the extraction electrode is arbitrary, and may be rectangular, stepped or the like other than the tapered shape. Further, the extraction electrode may be bent to be a surface mounting type electrode as in the above-mentioned embodiment, or may be a discrete type electrode. Further, the ends of the coil conductors and the reinforcing dummy conductors forming the extraction electrode may be only the conductors as in the above-described embodiment, or as shown in FIGS. A part of the coil conductor 18 may be extended and disposed on the back surface of the end portion 20 (or the reinforcing dummy conductor) of the coil conductor 18. Then, a structure in which the tip portion is folded back is adopted for electrical connection with an adjacent coil conductor. Further, as shown in FIGS. 7 and 8, the end portion 20 (or the reinforcing dummy conductor) of the coil conductor 18 may be provided on the front and back surfaces of the insulator sheet 14. Then, for electrical connection of the conductors provided on the front and back surfaces, a structure in which a via hole 25 is provided at the tip is adopted.

Further, in the above-mentioned embodiment, the hole for inserting the middle leg portion of the core is provided in the central portion of the insulator sheet, but such hole may not be provided. . In this case, the core is of a type having no middle leg. Further, other than the transformer, it may be a laminated coil used as a filter or may have no core.

[0014]

As is apparent from the above description, according to the present invention, since the end portion of the coil conductor is superposed on the reinforcing dummy conductor, the mechanical strength of the extraction electrode is increased and the terminal is improved. It is possible to obtain a laminated coil that is mounted on a printed circuit board or the like with sufficient mechanical strength without using a base. By omitting the terminal block, it is possible to reduce the height of the laminated coil.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a laminated coil according to the present invention.

FIG. 2 is a plan view showing an example of an insulator sheet used for the coil part of the laminated coil shown in FIG.

FIG. 3 is a plan view showing another example of an insulator sheet used for the coil part of the laminated coil shown in FIG.

FIG. 4 is a perspective view showing an appearance of the laminated coil shown in FIG.

FIG. 5 is a cross-sectional view of a coil conductor end portion of an insulator sheet used for a coil portion according to another embodiment.

FIG. 6 is a sectional view showing a modification of the embodiment shown in FIG.

FIG. 7 shows another embodiment, and is a cross-sectional view of a coil conductor end portion of an insulator sheet used for a coil portion.

FIG. 8 is a sectional view showing a modification of the embodiment shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Laminated coil 10 ... Coil part 14 ... Insulator sheet 18 ... Coil conductor 20 ... Coil conductor end 21 ... Reinforcing dummy conductor 22 ... Extraction electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Tanaka 2-26-10 Tenjin Tenjin, Nagaokakyo City, Kyoto Murata Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A laminated coil having a coil portion formed by laminating a plurality of insulator sheets each having a conductor for a coil provided on the surface thereof, the coil conductor protruding from an edge of each insulator sheet. A laminated coil, wherein an end electrode and a reinforcing dummy conductor that is not connected to the coil conductor are overlapped to form a lead electrode.