JPH0510340Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chip-type inductance element suitable as a component of a high-density packaged electronic device.

In order to obtain a high inductance element when constructing an electronic circuit, a coil conducting wire is generally wound around a drum-shaped or pot-shaped magnetic core. However, winding the coil requires time and effort, which is disadvantageous for mass production.

On the other hand, a ceramic capacitor that is small in size and has a large capacity in consideration of productivity can be obtained by appropriately printing wiring according to the frequency band used, and is therefore more advantageous than the above-described structure in terms of reliability and cost. This inductance element is made by forming a spiral conductor on a high magnetic permeability ferrite plate, or by depositing or coating a metal film on a cylindrical high magnetic permeability ferrite cylinder, covering the entire surface, and forming a spiral groove by machining. Some have a spiral conductor.

However, such a structure has a limit in obtaining a large inductance value, and unless it is formed in a high density in the same volume, it cannot be matched with other parts of a high-density electronic device.

By the way, a chip-shaped inductance element is known in which a through hole is formed in an insulating plate and a circular conductive pattern is formed on the upper and lower surfaces of the through hole (Japanese Patent Laid-Open No. 55-91804). This type of inductance element has a small length of about 1 cm, and the width of the conductive pattern itself is naturally small, so the through hole is also small like the conductive pattern. However, it is difficult to immediately determine at the manufacturing stage whether or not the conductive patterns on the upper and lower surfaces are reliably electrically connected through the through-holes, and there is a drawback that the electrical continuity cannot be determined unless it is measured at a separate inspection stage. Therefore, the manufacturing yield is poor.

In view of this, the present invention provides recesses at regular intervals in order to form a helical coil conductor in an inductance element piece, and attaches the coil conductor to the recesses by coating or plating to form a spiral coil conductor in the same volume. The main purpose of this invention is to eliminate the above-mentioned drawbacks by stacking inductance element pieces and ensuring electrical and mechanical connection between each element piece.

An embodiment of the present invention will be described in detail below with reference to the drawings.

1, 2, and 3 are a plan view, a front view, and a bottom view showing an example of the present invention. This inductance element consists of a ferrite plate 1 to which a spiral conductor is attached, a ferrite plate 2 to which a spiral conductor formed opposite to the winding direction of the spiral conductor of the ferrite plate 1 is attached, and a space between these ferrite plates 1 and 2. Ferrite plates 3 for providing insulation are alternately laminated.

The ferrite plate 1 constituting the first inductance element piece is made of a high permeability magnetic material with a constant thickness, and has coil conductor recesses 1a at constant intervals on the long side to form a helical coil conductor. (See Figure 4). The recessed portion 1a is provided to prevent the conductor from contacting the outside when the conductor is formed. Specifically, the concave notch 1 is
It is formed by press-molding ferrite powder into a mold having convex portions corresponding to a. Then, a spiral conductor 6 is formed by applying a silver-palladium spiral conductor or electroless nickel plating. Reference numeral 4 indicates electrodes formed continuously on the upper and lower surfaces of the short side of the ferrite plate 1. The spiral conductor 6 has a concave notch 1 located at the left and right ends.
A part of the conductor is formed to protrude from the back surface of a to form a left end 6a of the conductor and a right end 6b of the conductor.

The ferrite plate 2 constituting the second inductance element piece is the same as the ferrite plate 1 except that the spiral conductor 6' is formed in the opposite direction to the spiral direction of the conductor 6, as shown in FIG. The left end 6c of the conductor and the right end 6d of the conductor have opposite helical directions, so
It will be formed on the surface of the ferrite plate 2.
Therefore, the left ends 6a and 6c of the conductors of the first and second ferrite plates 1 and 2 overlap, and the right ends 6b and 6d of the conductors overlap.
will also overlap.

The insulating plate 3 interposed between the first and second inductance element pieces 1 and 2 is formed to have the same size as the first and second ferrite plates 1 and 2, as shown in FIGS. 7 and 8. It is made of high permeability magnetic material. Then, electrodes 4 that are continuous on the upper and lower surfaces similar to those of the ferrite plates 1 and 2 are formed on the short sides, and recessed portions 3 corresponding to the recessed portions 1a located at the left end or right end.
a is formed, and a conductor 3b that continues on the upper and lower surfaces of the recessed cutout 3a is formed. Therefore, by stacking the ferrite plate 1 on the insulating plate 3, the electrode 4 is connected, and the left end 6a of the conductor of the ferrite plate 1 and the conductor 3b of the insulating plate 3 are connected. Insulating plate 3
In addition to the example shown in FIG. 7, as shown in FIG. 1, a concave notch similar to that of the ferrite plate 1 of the first inductance element can be formed.

To construct a chip-like inductance element,
First and second ferrite plates 1, 2 and insulating plate 3
It is formed by laminating alternately. The second example shows an example in which the spiral conductor 6 is arranged in four stages; in this case, from the bottom, the insulating plate 3, second element piece 2, insulating plate 3', first
Element piece 1, insulating plate 3, second element piece 2, insulating plate 3',
The first element piece 1 and the insulating plate 3 are laminated in this order.
Incidentally, the insulating plate 3' means that the insulating plate 3' in the example shown in FIG. 7 is reversed and laminated. However, the uppermost and lowermost insulating plates 3
In order to electrically connect the electrode 4 and the conductor 3b,
By applying the conductive paint 7, the left and right electrodes 4, 4 are electrically connected via the four spiral conductors 6, 6'. Then, the laminated electrodes 4 are soldered to integrate them to complete the inductance element.

FIG. 9 is a plan view showing another example of the present invention.
In this example, the conductor forming portions of each of the ferrite plates 1, 2, and 3 except for the electrode forming portions on the long sides are removed so as to form a concave step shape. The recessed notch is formed in a predetermined manner from the recessed stepped surface. Therefore, when this inductance element is mounted in an electronic device, it is possible to avoid the possibility that other electronic components will come into contact with the conductor and cause a short circuit.

As described above, according to the present invention, in order to form a spiral coil conductor in a high magnetic permeability ferrite plate, recessed portions are provided at regular intervals, and a first inductance element piece is provided with a coil conductor attached to the recessed portions; A chip-type inductance element comprising a second inductance element piece in which coil conductors are formed in opposite directions, and an insulating plate made of a high magnetic permeability ferrite plate interposed between the first and second inductance element pieces, The helical coil conductor of the inductance element piece is formed continuously on the upper and lower surfaces and the recessed part by coating or plating, and partially protrudes from the recessed part located at the leftmost and rightmost ends to form the left and right ends of the conductor. 2
The helical coil conductor of the inductance element piece is formed by coating or plating so that the helical direction of the helical coil conductor of the first inductance element piece is continuous with the upper and lower surfaces and the recessed part, and the recessed part located at the leftmost and rightmost ends. The left and right ends of the conductor are provided at positions overlapping with the left and right ends of the helical coil conductor of the first inductance element piece, and the insulating plate has first and second inductances. A recessed part corresponding to the left or right end of the helical coil conductor of the element piece is formed, a conductor that is continuous on the upper and lower surfaces is formed in the recessed part, and the conductor and electrode of the uppermost and lowermost insulating plates are electrically connected. , electrodes continuously formed on the upper and lower surfaces of both short sides of the first and second inductance element pieces and the insulating plate were superimposed and treated with solder to electrically and mechanically integrate each element, thus forming a helical coil conductor. A plurality of inductances can be provided in a small volume, and therefore a large inductance value can be obtained in the same volume compared to a conventional structure, and it has the effect of ensuring consistency when mounted in a highly-densified electronic device.

In particular, in the case of a chip-shaped inductance element in which a through hole is formed in a conventional insulating plate and a circulating conductive pattern is formed on the upper and lower surfaces of the insulating plate through the through hole, the conductive pattern on the upper and lower surfaces is connected through the through hole. This solves the problem that it is difficult to easily determine from the outside whether or not conduction has been established reliably.

Furthermore, according to the present invention, each element can be connected by simply dipping it directly into a solder bath, and unlike conventional inductance elements, each element is not bonded with epoxy adhesive or low-melting glass and then heated under pressure. The mechanical connection can be ensured.

[Brief description of the drawings]

1, 2, and 3 are a plan view, a front view, and a bottom view showing an example of the present invention; FIGS. 4 and 5 are a plan view and a front view showing an example of the first inductance element piece; FIG. 6 is a plan view showing an example of a second inductance element piece, FIGS. 7 and 8 are a plan view and front view showing an example of an insulating plate, and FIG. 9 is a plan view showing another example of the present invention. It is. 1... First inductance element piece, 1a... Recessed part, 2... Second inductance element piece, 3...
Insulating plate, 3b... Conductor, 4... Electrode, 6... Spiral coil conductor, 6a... Left end of conductor, 6b... Right end of conductor, 7... Conductive paint.

Claims (1)

[Claims for Utility Model Registration] A first inductance element piece in which recesses are provided at regular intervals to form a helical coil conductor in a high magnetic permeability ferrite plate, and a coil conductor is attached to the recesses; and the coil conductor. A chip-type inductance element comprising a second inductance element piece formed in opposite directions, and an insulating plate made of a high magnetic permeability ferrite plate interposed between the first and second inductance element pieces, wherein the first inductance element The helical coil conductor of the piece is formed continuously on the upper and lower surfaces and the recessed part by coating or plating, and a part of the helical coil conductor is formed to protrude from the recessed part located at the leftmost and rightmost ends to form the left and right ends of the conductor, and a second inductance is formed. The helical coil conductor of the element piece is formed by coating or plating so that the helical direction of the helical coil conductor of the first inductance element piece is continuous on the upper and lower surfaces and the recessed part, and from the recessed part located at the left and right ends. The left and right ends of the conductor are formed to protrude partially, and the left and right ends of the conductor are provided at positions overlapping with the left and right ends of the helical coil conductor of the first inductance element piece, and the insulating plate has first and second inductances. A recessed part corresponding to the left or right end of the helical coil conductor of the element piece is formed, a conductor that is continuous on the upper and lower surfaces is formed in the recessed part, and the conductor and electrode of the uppermost and lowermost insulating plates are electrically connected. , characterized in that electrodes continuously formed on the upper and lower surfaces of both short sides of the first and second inductance element pieces and the insulating plate are overlapped and treated with solder to electrically and mechanically integrate each element. Chip type inductance element.