JP2001223121A - Thin transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin transformer where a core of laminated silicon steel plate is restrained from deteriorating in material yield, a ferrite core is prevented from being easily cracked, the transformer can be easily lessened in thickness, a core of material which is high in saturation magnetic flux density and hardly saturated with magnetism is utilized, and the transformer is small in size and never increased in mounting area even if it is lessened in thickness, furthermore the transformer can be easily fixed on a board, a secondary winding is restrained from increasing in number of turns, and a winding operation can be easily carried out. SOLUTION: Cylindrical cores are arranged in array, a secondary coil penetrates continuously through the cylindrical cores to from loops for a plurality of wire turns, and the cylindrical cores are fixed on the board with a primary conductor penetrating through the cores to from a thin transformer. Copper wires are inserted into the cores, the cores are mounted on board, both the ends of the copper wires are connected to a wiring pattern formed on board to form a primary coil and a secondary coil. Furthermore, a magnetic thin plate of amorphous ultra fine crystal alloy is rolled into a core, and a thin transformer is formed by the use of the core.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer used for an electronic device or a power converter such as an inverter.

[0002]

2. Description of the Related Art As a magnetic material of a transformer used in a conventional electronic device or a power converter such as an inverter, a laminated silicon steel plate or a Mn or Zn ferrite core is used.
Twisted wires are used for those with small current capacity for coil conductors wound around them, and for those with large current capacity,
In order to reduce the eddy current loss due to the AC magnetic field and to improve the workability of the wound wire, a double wire having insulated single wires arranged in parallel or a thick round wire is used. In the case of a laminated silicon steel sheet, an EI core is used, and in the case of a ferrite core, a block-shaped closed magnetic circuit core such as a ring core is used.
The secondary coil and the secondary coil were wound in multiple layers.

In order to transmit the power required for the transformer without magnetic saturation, a predetermined magnetic path cross-sectional area is required depending on the material of the core. There is. For this reason, when trying to form a thin core, in the case of a laminated silicon steel sheet or the like, a punched sheet having an irregular shape is formed, and the material yield is reduced, which is uneconomical.

[0004] In the case of a ferrite core, since the core is thin and large, there are problems such as warpage and breakage due to baking distortion during firing of the core, and it has been difficult to reduce the thickness. In addition, the conventional silicon steel sheet and ferrite materials have a large saturation magnetic flux density, so that magnetic saturation is apt to occur, so the core area for high power must be increased, and if the thickness is constant as described above, , It had to be a large transformer that required a considerable mounting board area. For this reason, it is necessary to further provide a mounting screw hole or the like for mounting the substrate, and the size is increased.
Also, a transformer having a large voltage step-up ratio, that is, a transformer having a large winding ratio, needs to increase the number of windings by making the secondary winding multilayer.

[0005]

In such a conventional transformer core, since the closed magnetic circuit core is block-shaped, there is no limitation that a certain height or more is required. It is an object of the present invention to eliminate a decrease in the material yield in the case of (1), to eliminate the problem that the ferrite core is liable to break, and to facilitate the reduction in thickness of the transformer. In addition, a core made of a material that has a higher saturation magnetic flux density and is less likely to be magnetically saturated is adopted without providing a mounting screw hole for mounting the board and increasing the outer shape. It is not to provide a thin transformer. Another object of the present invention is to make it easier to fix the board and to increase the number of secondary windings without increasing the number of windings, thereby forming a transformer having a large voltage step-up ratio.

[0006]

According to a first aspect of the present invention, a plurality of cylindrical cores are arranged in a transformer having a magnetic core wound with a primary coil and at least one or more secondary coils. In a transformer in which a conducting wire continuously penetrates the plurality of cylindrical cores to form a loop, and forms a secondary coil having a single or a plurality of winding numbers, each of the plurality of cylindrical cores penetrates the A thin transformer in which both ends of a conductor are fixed to a substrate, and the conductor is connected by a wiring pattern of the substrate to form a primary coil.

[0007] Instead of a single block-shaped core like a conventional transformer, the function of the transformer core is distributed to a plurality of tubular cores, and a loop is formed by a winding wire connecting the plurality of tubular cores. The core is fixed to the substrate by fixing both ends of the conducting wire penetrating for each core to the substrate, and both ends of each conducting wire are simultaneously connected to the wiring pattern provided on the substrate. You. The wiring pattern forms a primary coil by connecting the above-described conductors in parallel or in series. At this time, by connecting in parallel, it is possible to configure a transformer having a small primary side impedance and a large voltage boosting ratio.

In the case of ferrite, the cylindrical core can be easily formed into either a square tube or a cylinder. When a magnetic alloy ribbon is used, the core can be punched and laminated into a hollow square plate or disk. It is more suitable to form a longer core by winding it into a cylindrical shape. Further, the corners of the core wound in a cylindrical shape are deburred and rounded, or are thinly coated with an epoxy resin or the like so as not to damage the insulating film of the wound wire. A plurality of turns can be wound by repeatedly forming a loop into one turn with a winding wire that continuously penetrates a plurality of tubular cores, and further, at an arbitrary position of the plurality of tubular cores. Since the winding can be completed, a fractional number of windings can be selected, so that the secondary voltage can be set finer and more accurately. Further, the plurality of cores may be made of different materials, and the transmission characteristics with respect to the frequency of the transformer can be controlled by combining the cores having different frequency characteristics.

The thickness (height) of the transformer is determined by the thickness of the plurality of tubular cores, and the number of the tubular cores is increased according to the power, and the mounting area on the substrate is increased. Can be realized. Also, the shape of the area to be mounted on the board can be made to some extent by changing the arrangement method of the plurality of cylindrical cores, so that the shape can be designed according to the set board on which the transformer is mounted, and the height of the set can be reduced. Naturally, the size of the set can be reduced.

In a second aspect, a plurality of cylindrical cores are arranged in a transformer configuration in which a primary coil and at least one or more secondary coils are wound around a magnetic core. Both ends of a plurality of conductors penetrating therethrough are fixed to a substrate, and both ends of the conductors are connected by a wiring pattern of the substrate to form a one-piece connection.
A thin transformer comprising a secondary coil and a secondary coil.

A plurality of conductors obtained by adding the number of turns of the primary coil and the secondary coil are inserted into each of the plurality of cores, and each core has a plurality of holes each having both ends of the plurality of conductors provided on the substrate. At a predetermined location, and connected to a wiring pattern. At this time, it is desirable to use a double wire with a color such as a flat cable in order to insert the plurality of conductive wires without fail in predetermined positions of the plurality of holes.

The wiring pattern is such that, for example, when the primary conductors are connected in parallel and the secondary conductors are connected in series, the primary and secondary conductors are connected in series.
A transformer having a high step-up ratio by multiplying the next winding ratio by the number of cores can be formed, and the coupling coefficient does not decrease. It is desirable that the primary and secondary conductors have different thicknesses according to their respective current capacities. A plurality of cores can be connected to each other by a conductor, and each core can be mounted on a board and solder-dipped, so that a plurality of conductors penetrate each core according to the wiring pattern of a printed circuit formed in advance. Can be connected in series or in parallel to form a primary coil and any number of secondary coils.

According to a third aspect of the present invention, there is provided a thin transformer using a core formed by winding a magnetic thin plate of an amorphous ultrafine crystal alloy on the plurality of magnetic cores. As shown in FIG. 6, when a core formed by winding a magnetic thin plate of an amorphous ultrafine crystal alloy is used, the conventional manganese zinc (Mn, Z
Compared to the n) ferrite core, the saturation magnetic flux density is high and the magnetic permeability is large, so that a small core having a small magnetic path cross-sectional area can be formed. The core formed by winding a magnetic thin plate of an amorphous ultrafine crystalline alloy has a higher permeability and a higher frequency characteristic of Q characteristics than a silicon steel plate of the same thickness. Suitable for.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In order to constitute one transformer of a predetermined power, a plurality of transformers share power, a plurality of tubular cores are arranged, and a lead wire continuously passes through the plurality of tubular cores. Forming one or more windings of two or more
A secondary coil is formed, and the core is fixed to the substrate with a primary conductor penetrating each core, and at the same time, the primary conductors of each core are connected in series or in parallel to form one coil as a whole. Are configured. Also, a plurality of conductors having the same number as the total number of windings of the primary coil and the secondary coil are inserted into the plurality of core units, each core is mounted on a board, and both ends of the plurality of conductors are connected to the board. To form a primary coil and a secondary coil as a whole as a transformer.

[0015]

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows an embodiment of the present invention based on an equivalent circuit of the step-up transformer having a step-up ratio of 1: 8 shown in FIG. A 20 μm thick, 33.5 mm wide amorphous nanomicron crystal alloy ribbon (Nanopalm, manufactured by Alps Electric Co., Ltd.) is wound to form a cylindrical core having an outer diameter of 8.9 mm, an inner diameter of 4 mm, and a width of 33.5 mm. Then, the tube was covered with a heat-shrinkable tube and shrunk by heating to form a cylindrical core 3 having an external insulation treatment.

Next, a 0.7 mmφ 2
The four vinyl-coated stranded wires 2 are penetrated through the four cylindrical cores 3 and bent in a zigzag manner so that the four cores are arranged in parallel. A two-turn secondary coil was formed using the wire as a lead terminal. Next, four 1 mmφ urethane-coated copper wires having a length of about 70 mm for the primary coil were passed through the four cylindrical cores, and both ends were bent.
From the top surface of the substrate shown in FIG. 3 on which the terminal wiring of the secondary coil and the wiring pattern for connecting the primary coil in parallel are formed, the four primary coil copper wires and the secondary coil Both ends were inserted, the back surface of the substrate was solder-dipped, and solder-connected to the lands of the through holes on the back surface of the substrate to form the thin transformer shown in FIG.

[0017]

Embodiment 2 Similarly to Embodiment 1, based on the circuit diagram of the transformer having a winding ratio of 1 to 8 shown in FIG. 5, four cores identical to those used in Embodiment 1 are arranged in parallel. A total of three copper wires, 4 coils of 1 mmφ insulated copper wire 1 of about 76 mm length for the primary coil and 2 colored insulated copper wires of 0.7 mmφ for the secondary coil Inserted and bent both ends, the primary coil side is connected in parallel and the secondary coil side is connected in series. From the upper surface of the substrate shown in FIG. Both ends of the wire were inserted, the back surface of the substrate was solder-dipped, solder-connected to through-hole lands on the back surface of the substrate, and both ends were cut to a predetermined length to form the thin transformer shown in FIG.

[0018]

According to the present invention, there is no need to limit the height of a core of a conventional transformer to a fixed value or more for a block-shaped closed magnetic circuit core. Thus, a thin transformer having a large voltage step-up ratio can be realized. Also, a primary element and a secondary coil are configured by mounting on a board and using a wiring pattern of the board by using a core element in which the primary winding and the secondary winding of a plurality of cylindrical transformers are inserted into each core in common. By doing so, complicated winding work can be omitted.

[0019]

[Brief description of the drawings]

FIG. 1 shows a configuration diagram of a transformer according to a second embodiment.

FIG. 2 shows a configuration diagram of a transformer according to the first embodiment.

FIG. 3 is a rear view of the transformer mounting board according to the first embodiment.

FIG. 4 is a rear view of a transformer mounting board according to a second embodiment.

FIG. 5 shows a circuit diagram of a transformer having a winding ratio of 1: 8.

FIG. 6 shows a magnetic saturation characteristic of a core according to a material.

[Explanation of symbols]

 1 ... primary winding 2 ... secondary winding 3 ... cylindrical core 4 ... printed circuit board 5 ... aerial connection point of secondary coil

Claims (3)

[Claims] 1. A transformer comprising a magnetic material core wound with a primary coil and one or more secondary coils,
In a transformer in which a conductive wire continuously penetrates a plurality of tubular cores to form a loop and forms a secondary coil having one or more windings, a primary coil passes through each of the plurality of tubular cores. A thin transformer, wherein both ends of a conducting wire to be formed are fixed to a substrate, and the conducting wire is formed by being connected by a wiring pattern of the substrate. 2. A transformer comprising a magnetic core wound with a primary coil and one or more secondary coils,
A plurality of cylindrical cores are arranged, and both ends of a plurality of conductors penetrating each core are fixed to a substrate, and both ends of the conductors are connected by a wiring pattern of the substrate to form a primary coil and a secondary coil. A thin transformer characterized by: 3. The thin transformer according to claim 1, wherein a core formed by winding a magnetic thin plate of an amorphous ultrafine crystal alloy is used for the plurality of magnetic cores. Thin transformer.