CN112151238A - Transformer device - Google Patents

Abstract

The invention discloses a transformer, which comprises a cover plate and a magnetic core body, wherein the magnetic core body comprises a first side column, a second side column and a middle column connected with the first side column and the second side column, and a winding is wound on the middle column; the cover plate is fixed on the upper surfaces of the first side column and the second side column, wherein an air gap of the transformer is reserved in the cover plate. The transformer provided by the invention not only reduces the size, but also can realize full-automatic production and reduce the production cost.

Description

transformer

technical field

The invention relates to the field of magnetic components, in particular to a transformer.

Background technique

Generally, the composition of high withstand voltage transformer requires magnetic core body, insulating skeleton and insulating tape. With the increase of switching frequency, the miniaturization of magnetic components has become a trend in the industry. In the prior art, there is a transformer structure directly using nickel-zinc ferrite as the skeleton, and the magnetic core of the transformer structure includes an outer cylinder and an inner cylinder disposed inside the outer cylinder. This structure utilizes the insulating properties of the ultra-high resistivity of the nickel-core ferrite itself, eliminating the need for the winding skeleton, and realizing the miniaturization of the high-voltage transformer. However, this kind of structure has a complicated process, which requires winding wires on the inner cylinder, installing the outer cylinder, dispensing and baking, and finally welding the wire to the bottom of the outer cylinder. Since the wire needs to be fixed by an external fixture during the curing process of the glue, the fixture needs to enter the oven together during the curing process of the glue (usually several hours). Mass production not only requires a large number of fixtures, but any disturbance of the fixture will easily lead to the tilt of the inner cylinder, so that the air gap used for energy storage of the transformer changes, resulting in an increase in inductance error, a decrease in yield, and an increase in overall cost.

SUMMARY OF THE INVENTION

In view of this, the present invention proposes a transformer to reduce the size and production cost of the transformer.

According to a first aspect of the present invention, a transformer is proposed, comprising a cover plate and a magnetic core body, the magnetic core body comprising a first side column and a second side column, and a connection with the first side column and the second side column The connected central column, the winding is wound around the central column; the cover plate is fixed on the upper surface of the first side column and the second side column, wherein the gas of the transformer is left in the cover plate gap.

Preferably, the magnetic lines of force passing through the cover plate are parallel to the plane on which the outermost windings are located.

Preferably, the cover plate is provided of a material with an internal distributed air gap.

Preferably, the cover plate is provided as powder core material.

Preferably, the magnetic core body is I-shaped.

Preferably, the core body is provided as nickel zinc ferrite.

Preferably, there is no air gap between the cover plate and the upper surfaces of the first side column and the second side column of the magnetic core body.

Preferably, the first type pins of the transformer are located on the bottom surfaces of the first and second side posts, and the upper surfaces of the first and second side posts are opposite to the bottom surfaces.

Preferably, the first type of pin is formed by electroplating on the bottom surfaces of the first side pillar and the second side pillar.

Preferably, the bottom surfaces of the first side pillar and the second side pillar have recesses formed by etching.

Preferably, the first type of pin is formed by pasting a metal sheet on the concave portion.

Preferably, the first-type pins include primary-side first-type pins and secondary-side first-type pins, and the primary-side first-type pins are located on the bottom surfaces of the first side pillar and the second side pillar The first side of the secondary side is located on the second side of the bottom surfaces of the first side pillar and the second side pillar, and the first side is opposite to the second side.

Preferably, the winding is wound on the central column by automated winding.

Preferably, the winding includes a primary winding and a secondary winding, and the primary winding and the secondary winding are respectively wound from the first side column to the second side column in the direction of the entire said side column. on the center column.

Preferably, the head end and the tail end of the primary winding are welded to the first type pins of the primary side, and the head end and the tail end of the secondary winding are welded to the first type pins of the secondary side. .

Preferably, the winding further includes a shield winding wound on the central column.

Preferably, the shield windings are not electrically connected.

Preferably, the shield winding is wound outside the primary winding and the secondary winding.

Preferably, it also includes a second type of lead located on the upper surfaces of the first side column and the second side column, and the end of the shield winding is welded on the second type of lead.

Preferably, the distance between the first-type pins of the primary side and the first-type pins of the secondary side is set so as to conform to the standard electrical clearance and creepage distance.

The transformer structure provided by the invention directly forms the first type of pins by electroplating on the bottom surface of the magnetic core body, which is a transformer structure without skeleton, and reduces the size of the transformer. In addition, by setting the cover plate to be a powder core material, and setting the positions of the first-type pins of the primary side and the first-type pins of the secondary side, the transformer of the present invention can realize fully automatic production and reduce the production cost .

Description of drawings

1 is a structural diagram of a transformer according to an embodiment of the present invention;

2 is a schematic diagram of an internal magnetic field of a transformer according to an embodiment of the present invention;

3 is a structural diagram of a bottom pin of a transformer according to an embodiment of the present invention;

FIG. 4 is a structural diagram of a transformer according to another embodiment of the present invention.

Detailed ways

The present invention will be described in more detail below with reference to the accompanying drawings. In the various figures, like components are designated by like reference numerals. For the sake of clarity, various parts in the figures have not been drawn to scale. Additionally, some well-known parts may not be shown. For the sake of brevity, the structure obtained after several steps can be depicted in one figure. Numerous specific details of the present invention are described below, such as the structure, materials, dimensions, processing and techniques of each component, in order to provide a clearer understanding of the present invention. However, as can be understood by one skilled in the art, the present invention may be practiced without these specific details.

The invention provides a transformer, comprising a cover plate and a magnetic core body, the magnetic core body includes a first side column and a second side column, and a center column connected with the first side column and the second side column, Windings are wound on the central column; the cover plate is fixed on the upper surfaces of the first side column and the second side column, wherein an air gap of the transformer is left in the cover plate.

Specifically, as shown in FIG. 1 , the transformer 100 includes a cover plate 101 and a magnetic core body 102 , and the magnetic core body includes a first side column 110 and a second side column 112 , and the first side column 110 and all the The middle column 111 connected to the second side column 112 is wound with windings (not shown in the figure), and the cover plate 101 is fixed on the first side column 110 and the second side column 112 On the upper surface of the transformer, the cover plate 101 has an air gap of the transformer. No air gap is designed between the cover plate 101 and the upper surfaces of the first side pillar 110 and the second side pillar 112 of the magnetic core body 102 . In this embodiment, the magnetic core body 102 is an I-shaped magnetic core body structure. Preferably, the first side pillar 110 and the second side pillar 112 can be set as right quadrangular The column 111 may be configured as a polygonal column or a cylinder, which is not limited herein. The core body 102 is provided as nickel zinc ferrite.

The winding includes a primary winding and a secondary winding. First, the primary winding is wound on the entire central column in the direction from the first side column 110 to the second side column 112, and then The secondary winding is wound on the entire central column in the direction from the first side column 110 to the second side column 112 , and the secondary winding covers the primary winding. Both the primary winding and the secondary winding are electrically connected.

The cover plate 101 can be made of a material with internal distributed air gaps, preferably, the cover plate 101 is made of powder core material. The powder core material is generally a powder core material with low magnetic permeability (90u-9u), such as alloy powder, metal powder, iron powder, and the like.

As shown in FIG. 2 , it is a schematic diagram of the internal magnetic field of the transformer according to the embodiment of the present invention. Because the air gap of the transformer is left in the cover plate 101, the magnetic voltage drop uniformly drops in the cover plate, and passes through the magnetic field lines 125 in the cover plate 101 and the outermost winding 103. The planes at are parallel, so the component of the magnetic field line perpendicular to the winding plane is very small, mainly the horizontal component. Therefore, less eddy current losses are generated in the windings, reducing the AC resistance of the windings, and further reducing the losses of the transformer. In addition, because the air gap remains in the cover plate 101, there is no need to specially cushion the air gap between the cover plate 101 and the magnetic core body 102, and the step of cushioning the air gap with tape or insulating material is omitted, and automatic assembly can be realized production, greatly reducing the cost of small-sized transformers. Further, since the cover plate and the magnetic core body are closely bonded together, the heat loss generated on the cover plate 101 is more easily dissipated to the lower surface of the magnetic core body 102 and transmitted to the PCB, which improves the heat dissipation characteristics of the transformer. .

As shown in FIG. 3 , it is a schematic diagram of the first type of pins at the bottom of the transformer according to an embodiment of the present invention. The pins of the first type of the transformer are located on the bottom surfaces of the first side posts 110 and the second side posts 112 , and the upper surfaces of the first side posts 110 and the second side posts 112 are opposite to the bottom surfaces. The first-type pins include the primary-side first-type pins 121 and 122 and the secondary-side first-type pins 123 and 124. The primary-side first-type pins 121 and 122 are located on the first side post 110 and the first On the first side of the bottom surface of the two side pillars 112 , the secondary side first type pins 123 and 124 are located on the second side of the bottom surfaces of the first side pillar 110 and the second side pillar 112 , the first side and the second side pillar 112 side opposite. The winding can be wound on the central column 111 by means of automatic winding. Specifically, the winding includes a primary winding and a secondary winding, and the primary winding is first wound on the entire central column in the direction from the first side column 110 to the second side column 112 , and then the secondary winding is wound on the entire central column from the first side column 110 to the second side column 112 , and the secondary winding covers the primary winding superior. Wherein, an insulating material, such as insulating tape, is also wound between the primary winding and the secondary winding. The winding head and tail of the primary winding are spot-welded on the first-type pins 121 and 122 of the primary, respectively, and the winding head and tail of the secondary winding are spot-welded respectively on the primary winding. On the first type pins 123 and 124 of the primary side.

In this embodiment, the bottom surfaces of the first side pillars 110 and the second side pillars 112 have recesses formed by etching, and the first type pins are formed by pasting metal sheets in the recesses. Of course, those skilled in the art can also form the first type of pins of the transformer by directly plating metal on the bottom surfaces of the first side pillars 110 and the second side pillars 112 , which is not limited herein. Wherein, both the metal sheet and the electroplated metal can be selected from silver material.

In addition, the distance between the first type pins of the primary side and the first type pins of the secondary side is set so as to meet the standard electrical clearance and creepage distance, and a suitable distance C can be set to realize a high withstand voltage transformer.

The transformer structure provided by the invention directly forms the first type of pins by electroplating on the bottom surface of the magnetic core body, which is a transformer structure without skeleton, and reduces the size of the transformer. In addition, by setting the cover plate as a powder core material and setting the positions of the first type pins of the primary and secondary sides, the transformer of the present invention can realize fully automatic production and reduce the production cost.

As shown in FIG. 4 , it is a structural diagram of a transformer according to another embodiment of the present invention. The difference between the transformer of this embodiment and the first embodiment is that the winding further includes a shield winding 433 wound on the central column 411 . Wherein, the shield winding 433 is wound on the outside of the primary winding (431 or 432) and the secondary winding (431 or 432), and the shield winding 433 is not electrically connected. Between the primary winding or the secondary winding ( 431 or 432 ) and the shield winding 433 , an isolation material, such as insulating tape, is also wound. Further, the transformer further includes a second type of pin 421 located on the upper surfaces of the first side post 410 and the second side post 412 . The head and tail ends of the shield winding 433 are welded on the second type pins 421 .

In this embodiment, shield windings are wound on the outside of the primary winding and the secondary winding to prevent the magnetic lines of force generated by the primary winding and the secondary winding from dissipating heat to the outside and generating a near field to surrounding electronic components or circuit boards interference.

Embodiments in accordance with the present invention are described above, but these embodiments do not exhaust all the details and do not limit the invention to only the specific embodiments described. Obviously, many modifications and variations are possible in light of the above description. This specification selects and specifically describes these embodiments in order to better explain the principle and practical application of the present invention, so that those skilled in the art can make good use of the present invention and modifications based on the present invention. The present invention is to be limited only by the claims and their full scope and equivalents.

Claims (20)

1. A transformer comprises a cover plate and a magnetic core body,

the magnetic core body comprises a first side column, a second side column and a middle column connected with the first side column and the second side column, and a winding is wound on the middle column;

the cover plate is fixed on the upper surfaces of the first side column and the second side column,

wherein an air gap of the transformer is left in the cover plate.

2. The transformer of claim 1, wherein the magnetic flux lines passing through the cover plate are parallel to a plane in which the outermost winding is located.

3. The transformer of claim 1, wherein the cover plate is provided as a material with an internal distributed air gap.

4. The transformer of claim 1, wherein the cover plate is provided as a powder core material.

5. The transformer of claim 1, wherein the core body is i-shaped.

6. The transformer of claim 1, wherein the core body is provided as a nickel zinc ferrite.

7. The transformer of claim 1, wherein there is no air gap between the cover plate and the upper surfaces of the first and second legs of the core body.

8. The transformer of claim 1, wherein the first type of pin of the transformer is located on a bottom surface of the first and second side legs, an upper surface of the first and second side legs being opposite the bottom surface.

9. The transformer of claim 8, wherein the first type of pin is formed by plating on bottom surfaces of the first and second side legs.

10. The transformer of claim 8, wherein bottom surfaces of the first and second side legs have an etched recess.

11. The transformer of claim 10, wherein the first type of pin is formed by affixing a metal sheet to the recess.

12. The transformer of claim 8, wherein the first type of pin comprises a primary first type of pin located on a first side of the bottom surfaces of the first and second side legs and a secondary first type of pin located on a second side of the bottom surfaces of the first and second side legs, the first side being opposite the second side.

13. The transformer of claim 1, wherein the winding is wound on the center leg by automated winding.

14. The transformer of claim 1, wherein the winding comprises a primary winding and a secondary winding, and the primary winding and the secondary winding are respectively wound on the entire center leg in a direction from the first side leg toward the second side leg.

15. The transformer of claim 8, wherein the primary winding has a leading end and a trailing end spot-welded to the primary first-type pin and the secondary winding has a leading end and a trailing end spot-welded to the secondary first-type pin.

16. The transformer of claim 14, wherein the winding further comprises a shield winding wound around the center leg.

17. The transformer of claim 16, wherein the shield windings are not electrically connected.

18. The transformer of claim 16, wherein the shield winding is wound outside of the primary winding and the secondary winding.

19. The transformer of claim 16, further comprising a second type of pin on an upper surface of the first and second side legs, the shield winding being spot welded at a leading end and a trailing end to the second type of pin.

20. The transformer of claim 12, wherein the spacing between the primary first-type leg and the secondary first-type leg is set to meet a standard electrical gap and creepage distance.

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