CN209980935U

CN209980935U - Current transformer

Info

Publication number: CN209980935U
Application number: CN201921228900.6U
Authority: CN
Inventors: 李春; 龚志良; 朱仁波; 邱东强
Original assignee: Dongguan Mentech Optical and Magnetic Co Ltd
Current assignee: Dongguan Mentech Optical and Magnetic Co Ltd
Priority date: 2019-07-31
Filing date: 2019-07-31
Publication date: 2020-01-21
Anticipated expiration: 2029-07-31

Abstract

The utility model provides a current transformer, which comprises a body, the body comprises a first magnetic core and a second magnetic core, the second magnetic core comprises a center pillar winding part wound with a secondary coil and a first flange supporting part and a second flange supporting part which are connected with the flanges of the center pillar winding part on the first magnetic core in a supporting way, the first flange supporting part is connected with one end of the center pillar winding part and fixed on one side of the first magnetic core, the second flange supporting part is connected with the other end of the center pillar winding part and fixed on the other side of the first magnetic core; a primary coil is disposed in a gap between the center pillar winding portion and the first magnetic core. The embodiment of the utility model provides a current transformer has the magnetic core structural design mode of innovation, and compact structure, height are lower, the size is less not only, are favorable to automated production moreover.

Description

Current transformer

Technical Field

The utility model belongs to the technical field of the electric energy detection technique and specifically relates to a current transformer is related to.

Background

At present, current transformer wide application is in a plurality of power consumption fields such as detection and safeties, like motor protector, storage battery charging device, safe power consumption device, wireless charging device etc. current transformer theory of operation: the primary winding has few turns and is connected in a circuit of current to be measured in series, so that all current of the circuit flows, the secondary winding has more turns and is connected in series in a measuring instrument and a protection loop, and the secondary loop of the current transformer is always closed when the current transformer works, so that the impedance of a coil connected in series with the measuring instrument and the protection loop is very small, and the working state of the current transformer is close to short circuit. The current transformer converts a large current on the primary side into a small current on the secondary side for use, and the secondary side cannot be opened. With the development of miniaturization and lightness of electronic products, current transformers are also required to be miniaturized and ultrathin.

In the prior art, as shown in fig. 1, a magnetic ring of a current transformer is wound with a metal wire to form a secondary coil 2 ', a primary coil 3 ' sleeved with a rubber tube penetrates through the magnetic ring and is fixed on a bakelite base 1 ' through glue dispensing with the secondary coil 2 ', a secondary coil PIN 4 ' and a primary coil PIN 5 ' are arranged below the bakelite base 1 ', a PIN of the secondary coil 2 ' is peeled and dipped in tin and a lead wire are wound on the secondary coil PIN 4 ', and a PIN of the primary coil 3 ' is peeled and dipped in tin and the lead wire is wound on the primary coil PIN 5 '. However, the overall size of the current transformer is still large, and the requirement of a new application scene on low height cannot be met.

SUMMERY OF THE UTILITY MODEL

The utility model provides a current transformer, through the magnetic core structural design mode of innovation, compact structure not only, highly lower, the size is less, is favorable to automated production moreover.

In order to solve the technical problem, an embodiment of the present invention provides a current transformer, which includes a body, the body includes a first magnetic core and a second magnetic core, the second magnetic core includes a center pillar winding portion wound with a secondary coil, and a first flange supporting portion and a second flange supporting portion for supporting and connecting a flange of the center pillar winding portion to the first magnetic core, the first flange supporting portion is connected to one end of the center pillar winding portion and fixed to one side of the first magnetic core, and the second flange supporting portion is connected to the other end of the center pillar winding portion and fixed to the other side of the first magnetic core; a primary coil is disposed in a gap between the center pillar winding portion and the first magnetic core.

Preferably, a plurality of secondary coil lead pads and a plurality of primary coil pin pads are arranged on the top of the first flange supporting part and the top of the second flange supporting part.

Preferably, the primary coil is a copper foil winding.

Preferably, two primary coil terminal pins for welding are connected to the copper foil winding, and the end parts of the primary coil terminal pins are bent and molded towards the outer side of the copper foil winding;

the two primary coil terminal pins are attached to and welded on the same side of the bonding pad of the first flange supporting part or the bonding pad of the second flange supporting part; or

One of the primary coil terminal pins is attached to and welded to the pad of the first flange support portion, and the other primary coil terminal pin is attached to and welded to the pad of the second flange support portion.

Preferably, both sides of the copper foil winding are bent towards the second magnetic core to form bent portions, and the two bent portions of the copper foil winding are located between both sides of the center pillar winding portion and the first and second flange supporting portions.

Preferably, the end of each of the bending portions is folded outwards to form a folded portion.

Preferably, one pin of the secondary coil is welded on one secondary coil lead bonding pad of the first rib supporting part, and the other pin of the secondary coil is welded on the other secondary coil lead bonding pad of the first rib supporting part; or

And one lead of the secondary coil is welded on one secondary coil lead bonding pad of the second edge retaining support part, and the other lead of the secondary coil is welded on the other secondary coil lead bonding pad of the second edge retaining support part.

Preferably, one lead of the secondary coil is welded to one of the secondary coil lead pads of the first flange support portion, and the other lead of the secondary coil is welded to one of the secondary coil lead pads of the second flange support portion.

Preferably, the first magnetic core and the second magnetic core are both soft magnetic nickel-zinc ferrite or manganese-zinc ferrite magnetic cores.

Preferably, the first magnetic core is of a rectangular plate-shaped structure, the cross section of the second magnetic core is of an I-shaped structure, and the first magnetic core and the second magnetic core are fixedly connected through dispensing.

Compared with the prior art, the embodiment of the utility model provides a have following beneficial effect:

through designing new magnetic core structure, will first magnetic core, the second magnetic core equipment, first magnetic core with set up between the second magnetic core primary coil, the center pillar wire winding portion of first magnetic core twines secondary coil, wherein, primary coil, secondary coil's pin can be drawn forth in a flexible way and set up on first flange supporting part and/on the second flange supporting part.

The second magnetic core is of an H-shaped structure, the first magnetic core is of a plate type structure, and the first magnetic core and the second magnetic core are assembled, so that a magnetic ring in the prior art is replaced, and the height of the current transformer can be effectively reduced through the flat design.

In addition, center pillar wire winding portion is used for twining secondary coil adopts copper foil winding etc. primary coil locates center pillar wire winding portion with clearance between the first magnetic core can reduce current transformer's the equipment degree of difficulty effectively to be favorable to improving production efficiency.

Drawings

FIG. 1 is a schematic diagram of a prior art current transformer;

fig. 2 is a schematic structural diagram of a current transformer according to a first embodiment of the present invention;

fig. 3 is an exploded view of a current transformer according to a first embodiment of the present invention;

FIG. 4 is a schematic diagram of another construction of the secondary coil of FIG. 3;

fig. 5 is another structural schematic diagram of the primary coil of fig. 3;

fig. 6 is a schematic view of still another structure of the primary coil of fig. 3;

fig. 7 is a schematic structural diagram of a current transformer according to a second embodiment of the present invention;

fig. 8 is a schematic structural diagram of a current transformer according to a third embodiment of the present invention;

fig. 9 is a schematic structural diagram of a current transformer according to a fourth embodiment of the present invention;

fig. 10 is a schematic structural diagram of a current transformer according to a fifth embodiment of the present invention;

fig. 11 is a schematic structural diagram of a current transformer according to a sixth embodiment of the present invention;

wherein the reference numbers in the drawings of the specification are as follows:

1. a first magnetic core;

2. a second magnetic core; 21. a center pillar wire winding section; 22. a first rib support; 23. a second flange support part; 24. a secondary coil lead pad; 25. a primary coil pin pad;

3. a primary coil; 31. an end of a primary coil terminal pin; 32. a bending section; 33. a folding part;

4. a secondary coil.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The embodiment of the utility model provides a one:

referring to fig. 2 and 3, a first embodiment of the present invention provides a current transformer, which includes a body, the body includes a first magnetic core 1 and a second magnetic core 2, the second magnetic core 2 includes a center pillar winding portion 21 wound with a secondary coil 4, and a first rib supporting portion 22 and a second rib supporting portion 23 for connecting a rib of the center pillar winding portion 21 to the first magnetic core 1, the first rib supporting portion 22 is connected to one end of the center pillar winding portion 21 and fixed to one side of the first magnetic core 1, and the second rib supporting portion 23 is connected to the other end of the center pillar winding portion 21 and fixed to the other side of the first magnetic core 1; a primary coil 3 is provided in a gap between the center pillar winding portion 21 and the first magnetic core 1.

In the present embodiment, by designing a new magnetic core structure, the first magnetic core 1 and the second magnetic core 2 are assembled, the primary coil 3 is disposed between the first magnetic core 1 and the second magnetic core 2, and the center pillar winding portion 21 of the first magnetic core 1 is wound around the secondary coil 4, wherein the pins of the primary coil 3 and the secondary coil 4 can be flexibly led out and disposed on the first flange supporting portion 22 and/or the second flange supporting portion 23.

The second magnetic core 2 is of an H-shaped structure, the first magnetic core 1 is of a plate type structure, and the first magnetic core and the plate type structure are assembled, so that a magnetic ring in the prior art is replaced, and the height of the current transformer can be effectively reduced through the flat design.

In addition, the center pillar winding portion 21 is used for winding the secondary coil 4, and the primary coil 3 using a copper foil winding or the like is provided in the gap between the center pillar winding portion 21 and the first magnetic core 1, so that the difficulty of assembling the current transformer can be effectively reduced, thereby facilitating the improvement of the production efficiency.

Referring to fig. 3, in the embodiment of the present invention, in order to rationalize the structure, a plurality of secondary coil lead pads 24 and a plurality of primary coil pin pads 25 are disposed on the top of the first rib supporting portion 22 and the top of the second rib supporting portion 23. The electroplated pin bonding pad is designed on the second magnetic core 2, so that automatic welding of a wire and a pin can be effectively facilitated, and automatic production in the full process from full-automatic winding to lead welding is realized; the pad electrode on the second magnetic core 2 is used for surface mounting of an SMD structure, and can have better coplanarity.

In the embodiment of the present invention, it should be noted that the first magnetic core 1 and the second magnetic core 2 are both soft magnetic ferrite cores. Soft magnetic materials include nickel zinc ferrite and manganese zinc ferrite to ensure maximum operating temperature at 125 ℃, curie temperature Tc must exceed 125 ℃.

The embodiment of the utility model provides an in, first magnetic core 1 is rectangle platelike structure, and the cross-section of second magnetic core 2 is I shape structure, and first magnetic core 1 and second magnetic core 2 are glued fixed connection through the point, have saved original structure point and have glued fixed magnetic core and unable adjustment base and PIN and insert PIN needle process. Through kneading first magnetic core 1 and second magnetic core 2 like this, make it have the ultra-thin design of piece formula, possess the closed magnetic core structure of similar magnetic ring again, adopt the structure of two magnetic core laminating, can have lower height dimension, realize the minimizing of product PCB encapsulation occupation space under the equal electrical property condition simultaneously.

In the present embodiment, the primary coil 3 is preferably a copper foil winding, which has a good overcurrent capability and saves the winding process and the manufacturing time. Two primary coil terminal pins 31 for welding are connected to the copper foil winding, and the end parts of the primary coil terminal pins 31 are bent and formed towards the outer side of the copper foil winding; the two primary coil terminal pins 31 are soldered to the first flange support portion 22 or the second flange support portion 23 on the same side.

Referring to fig. 2 and fig. 3, in the first embodiment, the first magnetic core 1 and the second magnetic core 2 are made of nickel-zinc ferrite, the bottom boss of the second magnetic core 2 is electroplated with tin, the pad of the secondary coil pin and the pad of the primary coil pin are separated by a gap, the secondary coil 4 is wound on the columnar central pillar winding portion 21, the lead of the secondary coil 4 is welded on the bottom boss of the second magnetic core 2, the pin of the copper foil winding is also welded on the pad of the bottom boss of the second magnetic core 2, the coil winding is separated from the copper foil winding by a gap, and then the first magnetic core 1 and the second magnetic core 2 are assembled to be fixed by epoxy glue.

In the embodiment of the present invention, as the copper foil winding of the primary coil, the bottom of the pin is used as the pad portion, and the pin of various shapes can be designed to be suitable for various PCB packages according to different requirements of production and development, and the copper foil winding can be in a Z shape, a U shape or an omega shape. The winding start lead and the winding end lead of the secondary coil 4 may be in the same side direction, or the winding start lead and the winding end lead are not on the same side, that is, one lead of the secondary coil 4 is soldered to one of the secondary coil lead pads 24 of the first flange support 22/the second flange support 23, the other lead of the secondary coil 4 is soldered to the other secondary coil lead pad 24 of the first flange support 22/the second flange support 23, or one lead of the secondary coil 4 is soldered to one of the secondary coil lead pads 24 of the first flange support 22, and the other lead of the secondary coil 4 is soldered to one of the secondary coil lead pads 24 of the second flange support 23. Therefore, the utility model discloses have multiple structural design scheme, introduce in detail through following embodiment:

the embodiment of the utility model provides a two:

referring to fig. 4, on the basis of the first embodiment of the present invention, the position of the two pairs of the starting pin and the ending pin of the secondary winding is changed, and the connection relationship is as follows:

as shown in fig. 7, one lead of the secondary coil 4 is soldered to the secondary coil lead pad of the first flange support portion, and the other lead is soldered to the secondary coil lead pad of the second flange support portion, so that the start lead and the end lead of the secondary coil are soldered to opposite sides, respectively; and finally, assembling the first magnetic core 1, the second magnetic core 2, the secondary coil 4 and the like into a current transformer.

The embodiment of the utility model provides a three:

referring to fig. 5, on the basis of the first embodiment of the present invention, the third embodiment of the present invention improves the pins of the copper foil winding, both sides of the copper foil winding are all bent toward the second magnetic core 2 to form a bent portion 32, and the two bent portions 32 of the copper foil winding are located between both sides of the central pillar winding portion 21 and the first and second

flange supporting portions

22 and 23.

As shown in fig. 8, the starting lead of the secondary coil 4 is soldered to one of the secondary coil lead pads 24 of the second retaining portion 23, and the ending lead of the secondary coil 4 is soldered to the other of the secondary coil lead pads 24 of the second retaining portion 23, so that the starting lead and the ending lead of the secondary coil 4 are soldered to the same side; and finally, assembling the first magnetic core 1, the second magnetic core 2, the copper foil winding, the secondary coil 4 and the like into the current transformer shown in fig. 8.

The embodiment of the utility model provides a four:

referring to fig. 9, on the basis of the third embodiment of the present invention, the fourth embodiment of the present invention performs position conversion on the start line and the end lead of the secondary winding, one of the leads of the secondary coil 4 is welded on the secondary coil lead pad of the first flange supporting portion, and the other lead is on the secondary coil lead pad of the second flange supporting portion. So that the starting lead and the ending lead of the secondary coil are respectively welded on two opposite sides; and finally, assembling the first magnetic core 1, the second magnetic core 2, the copper foil winding, the secondary coil 4 and the like into the current transformer.

The embodiment of the utility model provides a five:

referring to fig. 6, on the basis of the first embodiment of the present invention, the fifth embodiment of the present invention improves the pins of the copper foil winding, both sides of the copper foil winding are all bent toward the second magnetic core 2 to form a bent portion 32, two bent portions 32 of the copper foil winding are located between both sides of the central pillar winding 21 and the first and second

flange supporting portions

22 and 23, and the end of each bent portion 32 is turned outward to form a turned portion 33.

As shown in fig. 10, the start lead of the secondary coil 4 is soldered to one of the secondary coil lead pads 24 of the second retaining portion 23, and the end lead of the secondary coil 4 is soldered to the other of the secondary coil lead pads 24 of the second retaining portion 23, so that the start lead and the end lead of the secondary coil 4 are soldered to the same side; and finally, assembling the first magnetic core 1, the second magnetic core 2, the copper foil winding, the secondary coil 4 and the like into the current transformer.

The embodiment of the utility model provides a six:

referring to fig. 11, on the basis of the fifth embodiment of the present invention, the fifth embodiment of the present invention performs position transformation on the start lead and the end lead of the secondary winding, one of the leads of the secondary coil 4 is welded on the lead pad of the secondary coil of the first flange supporting portion, and the other lead is welded on the lead pad of the secondary coil of the second flange supporting portion, so that the start lead and the end lead of the secondary coil are respectively welded on two opposite sides; and finally, assembling the first magnetic core 1, the second magnetic core 2, the copper foil winding, the secondary coil 4 and the like into the current transformer.

The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations are also considered as the protection scope of the present invention.

Claims

1. A current transformer is characterized by comprising a body, wherein the body comprises a first magnetic core and a second magnetic core, the second magnetic core comprises a center pillar winding part wound with a secondary coil, a first flange supporting part and a second flange supporting part, the first flange supporting part is used for connecting the flange of the center pillar winding part to the first magnetic core in a supporting mode, the first flange supporting part is connected with one end of the center pillar winding part and fixed on one side of the first magnetic core, and the second flange supporting part is connected with the other end of the center pillar winding part and fixed on the other side of the first magnetic core; a primary coil is disposed in a gap between the center pillar winding portion and the first magnetic core.

2. The current transformer of claim 1, wherein a plurality of secondary coil lead pads and a plurality of primary coil lead pads are disposed on a top portion of the first flange support and a top portion of the second flange support.

3. The current transformer according to claim 1 or 2, characterized in that the primary coil is a copper foil winding.

4. The current transformer according to claim 3, wherein two primary coil terminal pins for soldering are connected to the copper foil winding, and ends of the primary coil terminal pins are bent toward an outer side of the copper foil winding;

5. The current transformer according to claim 3, wherein both sides of the copper foil winding are bent toward the second magnetic core to form bent portions, and both of the bent portions of the copper foil winding are located between both sides of the center pillar winding portion and the first and second flange support portions.

6. The current transformer according to claim 5, wherein an end of each of the bent portions is folded outwardly to form a folded portion.

7. The current transformer of claim 2, wherein one lead of said secondary coil is soldered to one of said secondary coil lead pads of said first rib support, and another lead of said secondary coil is soldered to another of said secondary coil lead pads of said first rib support; or

8. The current transformer of claim 2, wherein one lead of said secondary coil is soldered to one of said secondary coil lead pads of said first flanged support and another lead of said secondary coil is soldered to one of said secondary coil lead pads of said second flanged support.

9. The current transformer of claim 1, wherein the first core and the second core are soft magnetic nickel-zinc-ferrite or manganese-zinc-ferrite cores.

10. The current transformer of claim 1, wherein the first magnetic core is a rectangular plate-shaped structure, the second magnetic core is an i-shaped structure in cross section, and the first magnetic core and the second magnetic core are fixedly connected by dispensing.