JP2831391B2 - Multilayer transformer with intermediate tap - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a laminated transformer, and more particularly to a laminated transformer with an intermediate tap.

[Related Art] Transformers are used for interstage coupling circuits such as analog circuits or pulse circuits including radio receivers, tuning circuits, filter circuits, oscillation circuits, and the like. The transformer is required to be small in size, capable of performing impedance conversion, polarity conversion, or changing the effective inductance value by changing the primary / secondary winding ratio.

Further, the magnetic permeability μ of the magnetic material of the transformer or the magnetic flux density B
However, in some cases, it is desired to use a transformer in a range having linearity with respect to the strength H of the magnetic field applied to the magnetic material.

It is the intermediate tap that is used to obtain a predetermined impedance conversion, polarity conversion or change in the effective inductance value.

FIGS. 11 to 19 and FIGS. 21 to 28 show such a laminated type of a conventional transformer with an intermediate tap.

These drawings are plan views illustrating a manufacturing process of a laminated transformer using a lamination technology such as a vapor phase method such as a printing technology, a sputtering or a vapor deposition technology. The illustration depends on the printing technique. In a manufacturing process of a laminated transformer with an intermediate tap, a plurality of laminated transformers are generally laminated on a wide easily peelable substrate, but only one laminated transformer will be described below for convenience of description. . Referring to FIG. 11, an electrically insulating magnetic ferrite is provided on the entire surface of an easily peelable substrate (not shown) in which a polyester (preferably a polyethylene terephthalate film) is formed on the surface of a substrate (such as aluminum) having a high flatness. The layer 41 is printed, and the conductive layer 43 for about a half turn forming a primary coil is printed thereon, and this is drawn out to the left to form a lead-out portion 45, which is used for about a half turn forming a secondary coil. The conductive layer 43 'is printed on the right side, and this is drawn out to the right side to form a lead portion 45'. To form an intermediate tap, as described below,
Bake out the drawer parts 45 and 45 'and connect the terminals as shown in Fig. 20.
69 and 73 may be appropriately connected externally, or the conductive layers 43 and 43 '
May be connected to each other by printing. The conductive layers 43, 43 'which make up the primary and secondary coils are printed spaced apart from one another in the lateral direction. Next, as shown in FIG. 12, the conductive layers 43 and 43 '
The magnetic ferrite layer 49 is printed except for the ends 47 and 47 '. Next, as shown in FIG. 13, the conductive layers 51 and 51 'for about half turn are printed by connecting to the one end portions 47 and 47'. Next, the 14th
As shown, the magnetic ferrite layer 55 is printed leaving one end 53, 53 'of the conductive layer 51, 51', and then, as shown in FIG.
Conductive layers 57, 5 for about half turn connected to one end 53, 53 '
Print 7 '. Next, as shown in FIG. 16, the conductive layers 57 and 57 '
The magnetic ferrite layer 61 is printed except for one end 59, 59 '. To obtain the desired number of coil windings, FIGS. 12 to 15
What is necessary is just to repeat the lamination process of a figure as needed. After finishing the desired lamination, as shown in FIG. 17, one end of the conductive layers 57 and 57 '
The conductive layers 63 and 63 'are printed by being connected to 59 and 59', and are drawn out to the left or right side, respectively, to form lead portions 65 and 65 '. Next, as shown in FIG.
After printing, sinter the necessary external lead terminals 69, 71, 7
By burning 3 and 75 and externally connecting the terminals 69 and 73 appropriately, a laminated transformer with an intermediate tap can be obtained. FIG. 20 is a schematic circuit diagram of the laminated transformer with the intermediate tap.

FIGS. 21 to 28 show a manufacturing process of a laminated transformer with an intermediate tap according to another conventional technique. First, as shown in FIG. 21, a magnetic layer 81 such as a magnetic ferrite is printed on an easily peelable substrate (not shown), and a conductive layer 83 for a primary coil for about a half turn is printed on the surface. Print. Note that one end of the conductive layer 83
85 is drawn out to the side of the magnetic layer 81. Next, as shown in FIG. 22, the conductive layer 83 is covered with a magnetic layer 89 except for one end 87 of the conductive layer 83. Next, as shown in FIG. 23, the conductive layer 91 for about half turn is printed by connecting to one end 87 of the conductive layer 83. It will be apparent that the same lamination as in FIG. 23 may be performed in order to obtain a primary coil having a desired number of windings. After completing the desired laminated, as in the FIG. 24, the magnetic layer 95 is printed, leaving one end portion 93 of the conductive layer 91, then, about _^1/4 connected to one end 93
The conductive layer 97 for the turn is printed and drawn out to the side of the magnetic layer 95 to form an intermediate tap lead-out portion 99, which is connected to a part of the conductive layer 97 for the primary coil and the conductive layer 101 for the secondary coil. Print. Next, as shown in FIG. 25, the magnetic layer 105 is printed leaving one end 103 of the conductive layer 101, and then the conductive layer 107 is connected to the one end 103 and printed for about a half turn. It will be apparent that the same stacking as in FIG. 25 may be performed to obtain a secondary coil having a desired number of turns. After finishing the desired lamination,
26, as shown in FIG. 26, leaving one end 109 of the conductive layer 107,
1 and then connected to one end 109 to print the conductive layer 113 for about half a turn, and connect one end 115 of the conductive layer 113 to the magnetic layer 1.
Pull out to 11 side. Next, as shown in FIG.
7 is printed on the entire surface, sintered, and the necessary external terminals 119, 121, 1
By performing baking of 23, a laminated transformer with an intermediate tap is obtained. FIG. 29 is a schematic circuit diagram of the laminated transformer with the intermediate tap.

[Problems of the Prior Art] In the laminated transformer with an intermediate tap obtained by the laminating process of FIGS. 11 to 19, the thickness of the laminated transformer can be reduced because the primary coil and the secondary coil are laminated in parallel. Although it has an effect, it has a problem that the width increases. Further, in the case of the laminated transformer with the intermediate tap shown in FIGS. 21 to 28, since the primary and secondary coils are sequentially laminated, there is an effect that the lateral width of the laminated transformer can be suppressed, but the thickness is increased. Is caused. As described above, none of the laminated transformers with intermediate taps sufficiently satisfies the demand for miniaturization required for the laminated transformer.

[Overview of the Present Invention] An overview of the present invention will be described with reference to FIG. 1 to FIG. As shown in FIG. 1 to FIG. 9, according to the present invention, a plurality of conductive pieces for forming a primary coil winding and a plurality of conductive pieces for a secondary coil winding are simultaneously parallel and each conductive piece is Since the laminated transformer is circulated in the opposite direction around the common circling axis via the magnetic piece, a laminated transformer with an intermediate tap having a reduced width and thickness can be obtained. The intermediate tap connects the primary coil conductive piece and the secondary coil conductive piece at the beginning or end of the primary coil conductive piece and the secondary coil conductive piece printed in opposite directions as shown in FIG. It is obtained by connecting and pulling out to the side of the magnetic piece.

That is, the present invention comprises an alternate laminate of two sets of a plurality of conductive pieces and a plurality of magnetic pieces for forming two sets of coils, and each set of the conductive pieces is disposed on an edge of the magnetic piece. Connected to adjacent conductive strips to form a coil, wherein the two sets of coils wrap around opposite common axes in opposite directions to form substantially non-overlapping coils. Each of the coils has one of upper and lower ends connected to each other inside the multilayer body and one intermediate tap is drawn out, to provide a laminated transformer with intermediate taps.

In another embodiment, adjacent magnetic pieces of the plurality of magnetic pieces are formed in a mutually complementary shape, and the thickness of the laminated transformer is adjusted to be constant.

According to still another mode, an insulating non-magnetic material is formed in a part of the magnetic piece to improve linearity.

[Detailed Description of the Invention] Fig. 1 is a plan view showing a manufacturing process of a laminated transformer with an intermediate tap according to the present invention.

Hereinafter, an example of the laminated transformer with an intermediate tap according to the present invention will be described in detail.

In the manufacturing process of the laminated transformer with an intermediate tap, a plurality of laminated transformers are simultaneously laminated on the same easily peelable substrate, but a single laminated transformer will be described below for convenience of explanation. In the following description, the laminating step will be described as using a conventional well-known printing technique, but it is also possible to perform laminating by a thin film method such as a sputtering method or an evaporation method. Various conventional conductors can be used as the material of the coil winding forming conductive piece, and various conventional magnetic substances can also be used as the material of the magnetic piece. Examples of possible materials for the conductive piece include Ag (silver), Au
Paste materials obtained by kneading powders such as (gold), Cu (copper), Pd (palladium), and Ag-Pd (silver-palladium) alloy with an appropriate binder can be considered. A paste-like material obtained by kneading various binders is conceivable. Furthermore, in the case of the evaporation method, Al, NiCr-Au, C
Any conductive material such as r-Au is conceivable. Further, as the magnetic piece, a magnetic material such as Zn ferrite, Mn-Zn ferrite, Ni-Cu-Zn ferrite, and Fe ₂ O ferrite can be considered.
In addition, as described later, the magnetic resistance of the magnetic circuit including the magnetic core is increased, and the magnetic core is used in a range where the BH (μ-H) curve of the magnetic core has linearity. It is also possible to laminate an insulating non-magnetic material on the portion. The insulating non-magnetic material can be selected from non-magnetic ferrite such as Cu-Zn ferrite, an alumina layer, barium titanate, and titanium oxide.

The manufacturing process of one example of the laminated transformer with an intermediate tap according to the present invention shown in FIGS. 1 to 9 will be described.

As shown in FIG. 1, a magnetic layer 1 can be printed on the entire surface of an easily peelable substrate (not shown), and a magnetic piece 2 for correcting a printing step can be printed on the center of the magnetic layer 1. is there. Next, as shown in FIG. 2, the conductive piece 3 for the primary coil winding (hereinafter simply referred to as the primary coil conductive piece) and the conductive piece 3 'for the secondary coil winding (hereinafter simply referred to as the secondary coil conductive piece). Called a piece)
Are extended in a nested shape, the ends 5 of the coil conductive pieces are connected, and they are pulled out to the sides of the magnetic layer 1 to form intermediate taps 5 '. Number of turns of the primary and secondary coil conductor strips is preferably about _^1/4 number of turns. The same applies to the following conductive pieces. Next, as shown in FIG. 3, one end portions 7, 7 'of the primary and secondary coil conductive pieces 3, 3' are left.
The magnetic pieces 9, 9 'are printed on both sides. The magnetic pieces 9 and 9 ′ are preferably printed so as to have a shape complementary to the magnetic piece 2.
The same applies to the following magnetic pieces. Next, as shown in FIG. 4, the primary and secondary coil conductive pieces 11, 3 'are connected to one end portions 7, 7' of the primary and secondary coil conductive pieces 3, 3 ', respectively.
Print 1 '. Next, as shown in FIG.
The magnetic piece 13 is printed on the center part except for the side part 1 '. Next, as shown in FIG. 6, the conductive strips 15, 15 'are connected to the side portions of the conductive strips 11, 11' and shifted from each other to print the conductive strips 15, 15 '. Next, the seventh
As shown in the figure, 19 and 19 'are printed on both sides except for one end 17, 17' of the conductive piece 15, 15 '. In order to obtain a primary coil and a secondary coil having a desired number of windings, the same steps as in FIGS. 3 to 6 may be repeated. Next, as shown in FIG.
The conductive pieces 21 and 21 'are printed by connecting to the one end portions 17 and 17', and the printed pieces are drawn out to the portions of the magnetic pieces 19 and 19 'to form the input / output lead portions 23 and 23' of the laminated transformer with the intermediate tap. . Next, as shown in FIG. 9, a magnetic piece (not shown) is printed in the center and a magnetic layer (not shown) is printed on the entire surface, and then sintered, and necessary external lead-out terminals 25, 27, and 29 are printed. , And a laminated transformer with an intermediate tap is obtained. FIG. 10 is an equivalent circuit diagram of a laminated transformer with an intermediate tap obtained by the laminating process of FIGS. 1 to 9.

As a second example of the laminated transformer with an intermediate tap according to the present invention, a laminated transformer in which an insulating non-magnetic layer (for example, a non-magnetic ferrite such as Cu-Zn ferrite) is laminated on a part of the above-described magnetic piece is also available. Conceivable.

The embodiment of the laminated transformer with the intermediate tap according to the present invention has been described above. However, it is also possible to increase or decrease the distributed capacitance between the conductive pieces by printing the primary / secondary coil conductive pieces appropriately shifted. It is. It will be apparent that the size and shape of the conductive piece and the magnetic piece can be arbitrarily changed.

[Effects of the Present Invention] The effects of the present invention will be described with respect to the laminated transformer with an intermediate tap according to the present invention shown in FIGS. 1 to 10. When the primary coil and the secondary coil are simultaneously parallel and common. Since the laminated transformer is laminated substantially around the circular axis, a laminated transformer with reduced thickness and width can be obtained.

Further, by forming an insulating non-magnetic layer on a part of the magnetic piece, the magnetic field strength H to which the magnetic permeability μ of the magnetic material is applied is applied.
It is possible to use a transformer within a range having linearity with respect to, and it is also possible to improve the linearity of the transformer.

Further, by printing adjacent magnetic pieces in a mutually complementary shape, a laminated transformer having a constant thickness can be obtained.

Although the preferred embodiments of the present invention have been described above, it will be apparent to those skilled in the art that various modifications and applications can be made without departing from the technical spirit of the present invention.

For example, although a laminated transformer with an intermediate tap is disclosed in which the intermediate tap is formed at the beginning of the coil winding, the transformer formed at the end of the coil winding should also be included in the technical concept of the present invention. Further, those skilled in the art can appropriately change the positions, shapes, sizes, and the like of the external extraction terminals and the coil windings.

[Brief description of the drawings]

1 to 9 are plan views showing the steps of manufacturing a laminated transformer with an intermediate tap according to the present invention. FIG. 10 is an equivalent circuit diagram of a laminated transformer with an intermediate tap according to the present invention obtained by the manufacturing process of FIGS. 1 to 9. 11 to 19 are plan views illustrating the steps of manufacturing a conventional laminated transformer with an intermediate tap. FIG. 20 is a schematic circuit diagram of a conventional laminated transformer with an intermediate tap obtained by the manufacturing process of FIGS. 11 to 19. 21 to 28 are plan views illustrating the steps of manufacturing a conventional laminated transformer with an intermediate tap. FIG. 29 is a schematic circuit diagram of a conventional laminated transformer with an intermediate tap obtained by the manufacturing process of FIGS. 21 to 28.

Claims (4)

(57) [Claims] 1. An alternating laminate comprising two sets of a plurality of conductive pieces and a plurality of magnetic pieces for forming two sets of coils,
Each set of conductive strips is connected to an adjacent conductive strip via the edge of the magnetic strip to form a single coil, and the two sets of coils are inverted relative to each other about respective offset common axes. Forming a coil that circulates in the direction and does not substantially overlap each other, wherein each of the coils has one of its upper and lower ends connected to each other inside the laminate and one intermediate tap is drawn out. Multilayer transformer with intermediate tap. 2. An apparatus according to claim 1, further comprising an alternating laminate of two sets of a plurality of conductive pieces and a plurality of magnetic pieces for forming two sets of coils, wherein each set of the conductive pieces is adjacent to each other via an edge of the magnetic piece. Are connected to the conductive pieces to form a coil, and the two sets of coils form coils that circumnavigate in opposite directions about their respective offset common axes and do not substantially overlap each other. In each of the coils, one of the upper and lower ends is connected to each other inside the laminated body and one intermediate tap is drawn out, and adjacent magnetic pieces of the plurality of magnetic pieces are formed in a complementary shape to each other. A laminated transformer with an intermediate tap. 3. The laminated transformer with an intermediate tap according to claim 1, wherein said magnetic piece is formed with an insulating non-magnetic material at a part thereof. 4. The laminated transformer with an intermediate tap according to claim 1, wherein the laminated transformer is entirely sintered.