JP2012217227A - Switching power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switching power supply device that can suppress an increase in the number of components and labor hour for mounting.SOLUTION: In a switching power supply device that supplies input power to a primary coil of a transformer by switching operation of a switching element and draws output power from a secondary side circuit formed on a secondary coil of the transformer, the transformer is composed of a plurality of transformers A and B, each of primary coils 1a and 1b of each of the transformers A and B is connected in series to each other, and each of the primary coils 1a and 1b of each of the transformers A and B is composed of one conductor.

Description

  The present invention relates to a switching power supply device including two or more transformers, and particularly suppresses an increase in the number of components and the number of mounting steps.

  A conventional switching power supply apparatus has been proposed with a configuration and method for reducing heat loss generated in a transformer. For example, the transformer of the switching power supply device is composed of a plurality of transformers to suppress current concentration, reduce heat generation due to loss, and improve efficiency (see, for example, Patent Document 1).

JP 2008-178205 A

The conventional switching power supply device is shown only for connection on a circuit, and does not show any description regarding the problem of having a plurality of transformers. In this way, when configuring a transformer with multiple,
(1) The number of parts of the transformer increases.
(2) As the number of components in (1) increases, the number of mounting steps for mounting also increases.
There was a problem.

  The present invention has been made in order to solve the above-described problems. Even if the present invention is configured to include a plurality of transformers, a switching power supply device that can suppress an increase in the number of components and the number of mounting steps The purpose is to provide.

This invention
In the switching power supply that supplies input power to the primary winding of the transformer by the switching operation of the switching element and extracts output power from the secondary side circuit formed in the secondary winding of the transformer.
The transformer includes a plurality of transformers, the primary windings of the transformers are connected in series, and the primary windings of the transformers are configured of one conductor.

The switching power supply device of the present invention
In the switching power supply that supplies input power to the primary winding of the transformer by the switching operation of the switching element and extracts output power from the secondary side circuit formed in the secondary winding of the transformer.
Since the transformer is composed of a plurality, each primary winding of each transformer is connected in series and each primary winding of each transformer is composed of one conductor,
An increase in the number of components and mounting man-hours can be suppressed.

It is a top view which shows the structure of the transformer of the switching power supply apparatus of Embodiment 1 of this invention. It is a top view which shows the structure of the transformer of the switching power supply apparatus of Embodiment 2 of this invention. It is a top view which shows the structure of the other transformer of the switching power supply device of Embodiment 2 of this invention.

Embodiment 1 FIG.
Embodiments of the present invention will be described below. 1 is a plan view showing a configuration of a primary winding, a core, and a cooling path of each tunnel of the switching power supply according to Embodiment 1 of the present invention. In the figure, a switching power supply device supplies input power to a primary winding of a transformer by switching operation of a switching element, and takes out output power from a secondary circuit formed in the secondary winding of the transformer. The transformer is composed of a plurality of transformers A and B. The transformer A includes a primary winding 1a, a terminal portion 2a for connecting the primary winding 1a and the circuit board 10, and a core 4a. The transformer B includes a primary winding 1b, a terminal portion 2b for connecting the primary winding 1b and the circuit board 10, and a core 4b.

  The transformer A and the transformer B are connected in series by connecting the primary windings 1 a and 1 b at the connection portion 6. The primary windings 1 a and 1 b include a plurality of claws 3 for fixing the primary windings 1 a and 1 b on the circuit board 10 and terminal portions 2 a and 2 b for connecting to the circuit board 10. In addition, the core 4a and the core 4b in a figure show the formation area of each core 4a, 4b, and show similarly also in the following embodiment.

  Thus, the primary winding 1a and the primary winding 1b are connected in series, and are comprised by one conductor. The conductor is preferably a single metal flat plate wound around a predetermined gap. Thus, if it is constituted by one conductor, that is, one metal flat plate, it can be easily manufactured by press working. Further, by mounting the primary windings 1a and 1b formed of the metal flat plate on the circuit board 10, the connection with the switching elements on the primary side of the transformers A and B becomes easy. Further, with this configuration, the primary windings 1a and 1b can be configured with a single component regardless of the plurality of transformers A and B.

  The terminal portions 2a and 2b, the claws 3, and the connecting portions 6 of the primary windings 1a and 1b are formed in a rectangular region 5 that circumscribes the winding portions of the primary windings 1a and 1b. By forming in this way, it is possible to reduce wasteful disposal of the metal flat plate. In the figure, the terminal portions 2a, 2b and the claws 3 are shown in a state of being punched out of a metal flat plate. When mounted on the circuit board 10, the terminal portions 2a, 2b and the claws 3 It is used by being folded back to the substrate 10 side, and is similarly shown in the following embodiments.

  Furthermore, the terminal portions 2a and 2b, the claws 3 and the connection portion 6 are formed outside the region where the cores 4a and 4b exist. Further, the cores 4a and 4b of the transformers A and B are arranged so that the short sides thereof are adjacent to each other. When the cores 4a and 4b are arranged in this way, for example, when the cooling path 11 by water cooling is formed, the cores 4a and 4b are disposed below the two cores 4a and 4b as shown in FIG. Therefore, the cores 4a and 4b can be efficiently cooled.

  In the switching power supply according to the first embodiment configured as described above, the primary windings of a plurality of transformers are formed by a single conductor, thereby suppressing an increase in the number of parts and mounting man-hours. Up can be suppressed. In addition, it is composed of a metal flat plate wound with a predetermined gap, and is mounted on the surface of the circuit board, so that the mounting man-hours can be reduced while suppressing the mounting man-hours, compared to a so-called transformer with a litz wire wound. It becomes possible to pass an electric current.

Further, by providing the terminal portion, the claw, and the connection portion of the primary winding in a rectangular area circumscribing the primary winding, it is possible to reduce the wasteful disposal of the metal flat plate.
Further, by providing the terminal portion, the claw, and the connection portion of the primary winding outside the region where the core exists, the electrical relationship between the terminal portion, the claw and the core can be ensured satisfactorily.
Moreover, since a cooling path can be arrange | positioned along the longitudinal direction of a core with respect to a some core in parallel, the cooling performance of a core can be improved.

Embodiment 2. FIG.
In the first embodiment, the example in which the short sides of the cores 4a and 4b of the transformers A and B are adjacent to each other is shown. However, in the second embodiment, the cores 4a of the transformers A and B are shown. 4b are arranged so that the longitudinal sides of the 4b are adjacent to each other. FIG. 2 is a plan view showing the configuration of the primary winding, core, and cooling path of each tunnel of the switching power supply according to Embodiment 2 of the present invention. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. In this Embodiment 2, it arrange | positions so that the longitudinal direction sides of the cores 4a and 4b may adjoin. When the cores 4a and 4b are arranged in this way, for example, when the cooling path 12 by water cooling is formed, as shown in FIG. 2B, the cores 4a and 4b are placed below the center position of the two cores 4a and 4b. Therefore, both cores 4a and 4b can be efficiently cooled. The other parts have the same effects as those of the first embodiment.

  Moreover, although the example which winds the primary windings 1a and 1b in the same direction was shown in the said Embodiment 2, it is not restricted to this, For example, as shown in FIG. A case where the winding direction of 1b is wound in a different direction is also conceivable, and the same configuration as in the second embodiment can be adopted. By adopting such a layout of the primary windings 1a and 1b, the connection portion 6 can be securely fixed to the circuit board 10 even if only one claw 3 is used to fix the connection portion 6 of the primary windings 1a and 1b. Is possible.

  In each of the above embodiments, the number of transformers is two as an example. However, the present invention is not limited to this, and a plurality of transformers can be formed in the same manner as in each of the above embodiments. Similar effects can be achieved.

A, B transformer, 1a, 1b primary winding, 2a, 2b terminal, 3 claws,
4a, 4b Core, 5 Rectangular area, 6 Connection part, 10 Circuit board, 11, 12 Cooling path.

Claims (6)

In the switching power supply that supplies input power to the primary winding of the transformer by the switching operation of the switching element and extracts output power from the secondary side circuit formed in the secondary winding of the transformer.
A switching power supply device comprising a plurality of the transformers, wherein each primary winding of each transformer is connected in series, and each primary winding of each transformer is constituted by one conductor. 2. The switching power supply device according to claim 1, wherein each of the primary windings is configured by a metal flat plate wound with a predetermined gap and mounted on a circuit board. Each of the primary windings has a terminal portion for connecting to the circuit board and a claw for fixing to the circuit board,
3. The switching power supply device according to claim 2, wherein the terminal portion and the claw are provided in a rectangular region circumscribing each primary winding. The cores of the transformers are arranged so that the longitudinal sides of the cores are adjacent to each other, or arranged so that the short sides of the cores are adjacent to each other,
The switching power supply device according to claim 3, wherein the terminal portion and the claw are provided outside a region where the core of the transformer exists. The switching power supply device according to claim 2, wherein the connection portion of each primary winding is provided in a rectangular region circumscribing each primary winding. The cores of the transformers are arranged so that the longitudinal sides of the cores are adjacent to each other, or arranged so that the short sides of the cores are adjacent to each other,
6. The switching power supply device according to claim 5, wherein the connecting portion of each primary winding is provided outside a region where the core of the transformer exists.

Images