JP2517365Y2 - Power transformer - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used for mounting a printed circuit board used as a power source for a reproducing device such as a TV, a VTR, a copying machine, an office automation device such as a facsimile machine, etc. Regarding the power transformer.

[Prior art]

Usually, the power transformer is directly supported and fixed to the printed circuit board and conductively connected to the wiring on the circuit board in order to simplify and automate the assembly process, reduce the number of parts, and reduce the device space. That is, in this type of transformer, for example, as shown in the perspective view of FIG. 4, the central leg of the E-shaped iron core is fitted into the hollow portion of the bobbin 1 around which the coil 3 is wound to form the core 2, and The bobbin 1 is supported by bobbin legs 9 extending below both ends of the bobbin 1 so that the winding shaft is parallel to the surface of a printed circuit board (not shown).

Furthermore, on the bobbin leg 9, perpendicular to the printed circuit board surface,
Further, one ends of the lead pin rows 8 which are parallel to each other are embedded or held, the extraction end of the winding coil 3 is connected to them, and the other end is soldered to the wiring on the printed circuit board or arranged on the circuit board. It is inserted and connected to the connector.

Thus, in many cases, a plurality of printed circuit boards on which electrical components and the like are mounted are juxtaposed, or arranged in the vicinity of the mechanical components of the device. It is required to arrange the printed boards so as to be as close as possible to other printed circuit boards or other mechanical parts. Therefore, the height of the electric component from the surface of the printed circuit board must be made as low as possible, and particularly in FIG. 5 viewed from the side surface parallel to the lead pin row 8 of the power transformer as shown in FIG. As shown in the attention area A, the distance 7 between the leg of the bobbin and the core is narrowed, and dielectric breakdown near the lead pin (live part) from which high voltage is drawn becomes a problem and the electrical insulation standard required for electrical equipment is met. In order to fill the gap, the insulating plate 4 shown in FIG. 6 was inserted into the space to ensure a predetermined insulation.

[Problems to be solved by the device]

However, since the insulating plate 4 inserted in the space between the core 2 and the bobbin leg 9 is supported only by the contact friction between the lower surface of the core 2 and the upper surface of the bobbin leg 9, during the assembling process,
After completion of the assembly process, the insulating plate 4 may fall off during transportation of the device or use in a bad environment for the user, and it may not be possible to guarantee sufficient insulation of the transformer.

An object of the present invention is to provide a power supply transformer for mounting on a printed circuit board, in which an insulating plate does not easily fall off even if it is assembled in the same process as a conventional one.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a leg portion which is provided with a space provided in a central portion of a lower portion of a bobbin sandwiched therebetween, forms a support portion for a printed circuit board, and has a plurality of lead pins planted on a lower surface thereof. Elastic insulation that is fitted between the upper surface of the core and the lower surface of the core that is inserted into the hollow portion that penetrates through the upper portion of the bobbin and that surrounds the periphery of the upper portion of the bobbin. The insulating plate has a plate, and the insulating plate has a horizontal portion that substantially covers a lower surface of the core and an upper surface of a leg portion in which a plurality of lead pins are planted on the lower surface, and a predetermined distance from the edge of the horizontal portion to the space side. And an inclined portion formed in a part of the inclined portion and extending at a refraction angle of, and an inclined portion is formed in the middle of the vacant side end edge of the inclined portion and the bent portion of the horizontal portion. With a protrusion formed of a cut-and-raised piece bent at a predetermined cut-and-raised angle on the opposite side to the horizontal portion It has been made.

[Action]

Since it is configured as described above, after the assembly of the power supply transformer main body is completed, the insulating plate is inserted between the upper surface of the leg portion where the lead pins are planted and the lower surface of the core.
First, the inclined portion of the insulating plate is inserted into these gaps, and then the protrusion is inserted. The inclined portion forms a predetermined refraction angle with respect to the horizontal portion and is refracted and formed on the edge of the cavity side, and the projection portion has a predetermined cut on the side opposite to the side where the inclined portion is refracted with respect to the horizontal portion. Since the insulating plate is bent at a rising angle, and the insulating plate is made of an elastic material, the inclined portion and the protruding portion are elastically deformed to the side where the refraction angle and the cut-raised angle decrease. Enter the gap. Then, when the protrusion passes through the gap and reaches the space provided in the central portion of the lower portion of the bobbin, the protrusion elastically deformed due to the stress from the upper surface of the leg is removed from the upper surface of the leg. Is released, and the elastic force causes it to spring into the space below the upper surface of the leg. As a result, the tips of the protrusions are prevented from moving backward into the gap portion, so that even if a mechanical external force such as a vibration is applied to the power transformer, the insulating plate can prevent the upper surface of the leg portion from the lower surface of the core. It does not fall out of the gap.

〔Example〕

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

FIG. 1 is a perspective view of a power transformer equipped with an insulating plate according to an embodiment.

In order to facilitate understanding of the mounting state of the insulating plate, the core and the insulating plate are shown as partially cutaway views.

FIG. 2 shows a deformed state of the insulating plate in the step of inserting the insulating plate between the core and the bobbin leg portion, and FIG. 3 is a perspective view of the insulating plate.

It should be noted that description of the components and parts of the transformer, which have the same names and reference numerals as those of the conventional example, will be omitted.

As shown in FIG. 3, the insulating plate 4 is made of an elastic plate such as plastic or plastic molding which is not easily broken and is composed of a horizontal portion 10, a vertical portion 11, an inclined portion 6 and a protrusion 5.

The insulating plate 4 is formed by cutting the plate-shaped base material and bending such as pressing.

On the other hand, in the power transformer shown in FIG. 1, the core 2 is formed by inserting the E-shaped iron cores into the hollow portion of the bobbin 1 around which the coil 3 is wound from the openings at both ends, and the assembly of the transformer main body is completed. Then, the process proceeds to the step of inserting the insulating plate 4 into the transformer body shown in FIG.

The insulating plate 4 is press-inserted into the gap 7 between the core 2 and the bobbin leg 9 such that the protrusion 5 is on the bobbin leg 9 side from the insertion end side where the protrusion 5 is formed.

Since the height of the protruding portion 5 is slightly larger than the interval 7 between the core 2 and the bobbin leg portion 9, the protruding portion 5 enters the inclined portion 6 side while the tip is narrowly deformed, Eventually, the bobbin central space 12 is reached, the pressure is released, and the original shape is restored. Since the tip portion is brought into contact with and locked by the inner wall of the bobbin leg portion 9, the insulating plate will no longer return and drop from the transformer body.

In this embodiment, since the inclined portion 6 inclined toward the core side is provided and the protruding portion 5 formed by cutting and raising is formed therein, the protruding portion 5 reaching the bobbin central space 12 is formed on the bobbin. The angle formed with the upper surface of the leg portion 9 is the sum of the angle formed by the protrusion 5 with the inclined portion 6, that is, the cut-and-raised angle and the angle formed by the upper surface of the bobbin leg portion with which the inclined portion 6 contacts. Even with the relatively small cut-and-raised angle of the protrusion 5, the bobbin leg 9 can be securely locked to the inner wall.

The vertical portion 11 formed by bending the horizontal portion 10 prevents excessive insertion into the gap 7 between the core 2 of the insulating plate 4 and the bobbin leg portion 9 and also provides a sufficient extension of the surface of the insulating plate. It is formed to secure the insulation distance.

[Effect of device]

As described above, according to the present invention, the insulating plate fitted between the upper surface of the leg in which the lead pins are implanted and the lower surface of the core substantially covers the lower surface of the core and the upper surface of the leg. A horizontal portion, an inclined portion extending from the edge of the horizontal portion to the space side at a predetermined refraction angle, and an inclination between the edge of the inclined portion on the space side and the horizontal portion. The upper part of the leg part and the lower surface of the core part are composed of the protrusion part which is bent and bent at a predetermined angle to the side opposite to the side where the part is bent with respect to the horizontal part. When the insulating plate is inserted into the gap between the and the protrusions and passes through the gap and reaches the space in the lower center of the bobbin, the protrusions are stressed by the upper surface of the leg. From the upper surface of the leg portion due to elastic force, and is prevented from going backward into the gap portion. Even if the cut-and-raised angle of the raised part is small, the angle formed by the horizontal part and the projected part is the sum of the refraction angle between the horizontal part and the inclined part and the cut-and-raised angle between the inclined part and the projected part. Therefore, it is possible to reliably prevent the insulating plate from coming off from the gap portion and improve the insulation reliability of the power supply transformer mounted on the printed circuit board against a high voltage.

[Brief description of drawings]

1 is a perspective view of a power transformer according to an embodiment of the present invention, FIG. 2 is an explanatory view showing a process of inserting an insulating plate between a core and a bobbin leg, and FIG. 3 is a perspective view of the insulating plate. FIG. 4 is a perspective view of a conventional power supply transformer, FIG. 5 is a side view thereof, and FIG. 6 is a perspective view of a conventional transformer insulating plate. 1 ... Bobbin, 2 ... Core, 4 ... Insulator for transformer,
5 ... Protrusion, 8 ... Lead pin.

Claims (1)

(57) [Scope of utility model registration request] 1. A bobbin provided with a leg portion which is provided so as to sandwich a space provided in a central portion of a lower portion and which forms a support portion for a printed circuit board, and a hollow portion which is bored through the upper portion of the bobbin. A core wound around the upper part of the bobbin and wound around the upper part of the bobbin, a coil wound around the outer periphery of the bobbin in which the hollow part is bored, and planted on the lower surface of the leg part. In the power transformer having a plurality of lead pins serving as a connection portion with the wiring of the printed circuit board and the lead wire of the coil, the leg having the lower surface of the core and the plurality of lead pins planted on the lower surface. An insulating plate having elasticity that is fitted between the lower surface of the core and the upper surface of the leg portion in which the plurality of lead pins are planted on the lower surface. The horizontal part that almost covers and the empty space from the edge of the horizontal part. And an inclined portion extending at a predetermined refraction angle to the side, and an intermediate portion of the inclined portion formed on a part of the inclined portion, the edge of the inclined portion on the side of the space and the horizontal portion. In addition, the inclined portion is constituted by a protruding portion formed of a cut-and-raised piece bent at a predetermined cut-and-raised angle on the side opposite to the bent side with respect to the horizontal portion. A power transformer.