阅读说明：本技术 一种贴片式高频电感器及其制作方法 (Surface mount type high-frequency inductor and manufacturing method thereof ) 是由 唐小虎 曾德平 侯勤田 杨亚冰 于 2021-07-23 设计创作，主要内容包括：本发明公开了一种贴片式高频电感器及其制作方法,所述贴片式高频电感器包括磁芯及其线包,该贴片式高频电感器采用能提高电感量的闭合磁路结构,闭合磁路通过磁性胶水等磁性材料覆盖形成；所述磁芯的材质可以是镍锌铁氧体等软磁性材料或者陶瓷材料或者其他材料；所述磁芯包括中柱和位于所述中柱两端的两个边柱,所述边柱的底面设有电极；所述线包设于所述磁芯的中柱上,所述线包的两个端部分别固设于所述磁芯的两个边柱的电极底面上,形成贴片端子。采用能提高电感量的闭合磁路结构,再加上线包的两个端部分别固设于磁芯的两个边柱的电极底面上形成贴片端子的结构,可获得体积更小、电感量更大且能避免各个加工环节导致的磁芯破裂问题。(The invention discloses a chip type high-frequency inductor and a manufacturing method thereof, wherein the chip type high-frequency inductor comprises a magnetic core and a coil thereof, the chip type high-frequency inductor adopts a closed magnetic circuit structure capable of improving the inductance, and the closed magnetic circuit is formed by covering magnetic materials such as magnetic glue and the like; the magnetic core can be made of soft magnetic materials such as nickel-zinc ferrite and the like, ceramic materials or other materials; the magnetic core comprises a middle column and two side columns positioned at two ends of the middle column, and electrodes are arranged on the bottom surfaces of the side columns; the solenoid is arranged on the center pillar of the magnetic core, and two ends of the solenoid are respectively and fixedly arranged on the bottom surfaces of the electrodes of the two side pillars of the magnetic core to form a patch terminal. The closed magnetic circuit structure capable of improving the inductance is adopted, and in addition, the two end parts of the coil are respectively fixedly arranged on the bottom surfaces of the electrodes of the two side columns of the magnetic core to form a structure of a patch terminal, so that the magnetic core fracture problem which is smaller in volume, larger in inductance and capable of avoiding each processing link can be obtained.)

1. A chip high-frequency inductor comprises a magnetic core and a coil thereof, and is characterized in that the chip high-frequency inductor adopts a closed magnetic circuit structure capable of improving inductance;

the magnetic core comprises a middle column and two side columns positioned at two ends of the middle column, and electrodes are arranged on the bottom surfaces of the side columns;

the coil is arranged on the center pillar of the magnetic core, and two end parts of the coil are respectively and fixedly arranged on the bottom surface of the electrode to form a patch terminal;

the back of the chip type high-frequency inductor is solidified with magnetic glue which can form a closed magnetic circuit, or the back of the chip type high-frequency inductor is bonded with a mixture of a powdery magnetic material and a powdery adhesive which can form a closed magnetic circuit, or the back of the chip type high-frequency inductor is coated with a magnetic cover which can form a closed magnetic circuit;

the back of the chip high-frequency inductor is a part of the high-frequency inductor far away from the chip terminal.

2. The chip high-frequency inductor according to claim 1, wherein the cured magnetic glue at the top backside surface of the high-frequency inductor is a flat surface for facilitating SMT pick-up operations.

3. The patch type high-frequency inductor according to claim 1, wherein two ends of the coil are respectively provided with a bending portion after being led out from the central pillar of the magnetic core, and the bending portions are attached to the bottom surfaces of the electrodes of the side pillars.

4. The chip high-frequency inductor according to claim 3, wherein the bending portion extends from one side of the electrode bottom surface of the side pillar to the other opposite side.

5. The patch type high-frequency inductor according to any one of claims 1 to 4, wherein two ends of the coil are fixed to the bottom surfaces of the electrodes of the side posts by thermocompression bonding.

6. A manufacturing method of a patch type high-frequency inductor is characterized in that the end part of a winding is led out from a side column at one end of a magnetic core center column, then the winding is wound on the magnetic core center column to form a coil, the tail end of the coil is hung on the side column at the other end of the magnetic core center column, then the end part and the tail end of the winding of the coil are respectively fixed on electrodes on the bottom surfaces of two side columns to form patch terminals, and finally a closed magnetic circuit structure is formed on the back of the patch type high-frequency inductor;

the forming of the closed magnetic circuit structure can be realized by coating magnetic glue, bonding a mixture of a powdery magnetic material and a powdery adhesive on the back of the patch type high-frequency inductor or coating a magnetic covering;

the back of the patch type high-frequency inductor is a part of the patch type high-frequency inductor far away from the patch terminal.

7. The method for manufacturing a chip high-frequency inductor according to claim 6, wherein the step of applying the magnetic glue comprises the steps of: and pressing the back of the patch type high-frequency inductor into a cavity filled with magnetic glue, so that the magnetic glue is cured after reaching a preset height, thereby finishing coating.

8. The method for manufacturing a chip high-frequency inductor according to claim 7, wherein the bottom surface of the cavity is a flat surface, so that the top surface of the cured magnetic glue has a flat surface for facilitating an SMT pick-up operation.

9. A manufacturing method of a patch type high-frequency inductor is characterized in that a coil is wound on a magnetic core center column, two tail ends of the coil are respectively hung on magnetic core side columns at two ends of the magnetic core center column and welded to form a patch terminal, and finally a closed magnetic circuit structure is formed by coating a mixture of magnetic glue, a bonded powder magnetic material and a powder adhesive or coating a magnetic covering on the back of the patch type high-frequency inductor;

the back of the patch type high-frequency inductor is a part of the patch type high-frequency inductor far away from the patch terminal.

10. The method for manufacturing a chip high-frequency inductor according to claim 9, wherein the step of applying the magnetic glue comprises the steps of: pressing the back of the surface mount type high-frequency inductor into a cavity filled with magnetic glue, and curing the magnetic glue after the magnetic glue reaches a preset height, thereby finishing coating;

the bottom surface in the cavity is a plane, so that the top surface of the cured magnetic glue has a plane convenient for SMT absorption operation.

Technical Field

The invention relates to the technical field of chip high-frequency inductors, in particular to structural improvement of a chip high-frequency inductor and improvement of a manufacturing method of the chip high-frequency inductor.

Background

Most of the traditional chip high-frequency inductor structure is an open magnetic circuit, so that very high inductance on small-size high-frequency inductance is difficult to achieve, and under the trend of miniaturization of the chip high-frequency inductor, a plurality of requirements cannot be met, so that a closed magnetic circuit inductor is produced, and the technical effect of small-size large inductance can be achieved to a certain degree. In the manufacturing process of a common surface-mounted closed magnetic circuit inductor, the welding treatment of the tail end of a coil is mostly needed to fix the coil on a magnetic core. When the height value of the chip inductor is reduced to be less than 0.8mm, the end part welded with the wire in the magnetic core needs to be made very thin, so that the strength of the welded end part is reduced, and therefore, in the wire welding treatment process and the subsequent process, the welded part of the magnetic core is easy to break, so that the batch production is difficult to realize, or the defective rate of the batch production is too high.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a chip high-frequency inductor which comprises a magnetic core and a coil thereof, wherein the chip high-frequency inductor adopts a closed magnetic circuit structure capable of improving inductance; the magnetic core comprises a middle column and two side columns positioned at two ends of the middle column, and electrodes are arranged on the bottom surfaces of the side columns; the coil is arranged on the center pillar of the magnetic core, and two end parts of the coil are respectively and fixedly arranged on the bottom surface of the electrode to form a patch terminal; the back of the chip type high-frequency inductor is solidified with magnetic glue which can form a closed magnetic circuit, or the back of the chip type high-frequency inductor is bonded with a mixture of a powdery magnetic material and a powdery adhesive which can form a closed magnetic circuit, or the back of the chip type high-frequency inductor is coated with a magnetic cover which can form a closed magnetic circuit; the back of the chip high-frequency inductor is a part of the high-frequency inductor far away from the chip terminal.

The invention may also employ the following alternatives/preferences:

the solidified magnetic glue at the back top surface of the patch type high-frequency inductor is a plane convenient for SMT absorption operation.

Two ends of the solenoid are respectively provided with a bending part after being led out from the magnetic core center pillar, and the bending parts are attached to the bottom surfaces of the electrodes of the side pillars.

The bending part extends from one side of the bottom surface of the electrode of the side column to the other opposite side.

And two end parts of the coil are fixedly arranged on the bottom surface of the electrode of the side column in a hot-press welding mode.

The invention also provides a manufacturing method of the patch type high-frequency inductor, which comprises the steps of leading out the end part of a winding from a side column at one end of a magnetic core center column, winding on the magnetic core center column to form a coil, hanging the tail end of the coil on the side column at the other end of the magnetic core center column, respectively fixing the end part and the tail end of the winding of the coil on electrodes on the bottom surfaces of the two side columns to form patch terminals, and finally forming a closed magnetic circuit structure on the back of the patch type high-frequency inductor; the forming of the closed magnetic circuit structure can be realized by coating magnetic glue, bonding a mixture of a powdery magnetic material and a powdery adhesive on the back of the patch type high-frequency inductor or coating a magnetic covering; the back of the patch type high-frequency inductor is a part of the patch type high-frequency inductor far away from the patch terminal.

Optionally/preferably, the step of applying the magnetic glue comprises the following steps: and pressing the back of the patch type high-frequency inductor into a cavity filled with magnetic glue, so that the magnetic glue is cured after reaching a preset height, thereby finishing coating.

Further optionally/preferably, the bottom surface in the cavity is planar, so that the top surface of the cured magnetic glue has a planar surface for facilitating SMT pick-up operations.

The invention also provides a manufacturing method of the patch type high-frequency inductor, which comprises the steps of firstly winding a coil on a magnetic core middle column, then respectively hanging two tail ends of the coil on magnetic core side columns at two ends of the magnetic core middle column, welding to form a patch terminal, and finally coating a mixture of magnetic glue, a bonded powdery magnetic material and a powdery adhesive or coating a magnetic covering on the back of the patch type high-frequency inductor to form a closed magnetic circuit structure; the back of the patch type high-frequency inductor is a part of the patch type high-frequency inductor far away from the patch terminal.

Optionally/preferably, the step of applying the magnetic glue comprises the following steps: pressing the back of the surface mount type high-frequency inductor into a cavity filled with magnetic glue, and curing the magnetic glue after the magnetic glue reaches a preset height, thereby finishing coating; the bottom surface in the cavity is a plane, so that the top surface of the cured magnetic glue has a plane convenient for SMT absorption operation.

The beneficial effects of the invention include:

the closed magnetic circuit structure capable of improving the inductance is adopted, and in addition, the two end parts of the coil are respectively fixedly arranged on the bottom surfaces of the electrodes of the two side columns of the magnetic core to form a structure of a patch terminal, so that the magnetic core fracture problem which is smaller in volume, larger in inductance and capable of avoiding each processing link can be obtained.

Two tip of solenoid are drawn forth the back from the magnetic core center pillar and are extended and have one section portion of bending respectively to the face of keeping away from the magnetic core center pillar of two side posts, bend with the laminating of the electrode bottom surface of side post, this structure need not the welding position of attenuate magnetic core, and the tip of solenoid also need not to run through the welding position of magnetic core, and the welding position of consequently magnetic core has better welding strength. In addition, the end part of the coil can be bent to a required angle in advance without penetrating through the welding part of the magnetic core, so that a better attaching effect and more convenient welding operation can be realized.

Will the back of SMD high frequency inductor is impressed in the die cavity that is equipped with magnetic glue, the bottom surface in the die cavity is the plane, makes magnetic glue reaches the postcure of predetermined height to accomplish the coating, this way is simple and convenient, can once only form required closed magnetic structure and the required surface of being convenient for SMT absorption of follow-up technology, and applicable in the processing of multiple inductance volume demand, only need adjust the predetermined height of magnetic glue can obtain corresponding inductance volume.

Drawings

Fig. 1 is a schematic structural diagram of a chip inductor in the prior art.

Fig. 2 is a schematic structural diagram of another chip inductor in the prior art.

Fig. 3A is a schematic diagram of the structure of a magnetic core employed in one embodiment of the present invention.

Fig. 3B is a schematic structural diagram of a chip type high-frequency inductor according to an embodiment of the invention, which employs the magnetic core of fig. 3A.

Fig. 4A and 4B are schematic structural views of another magnetic core that can be used.

Detailed Description

The invention will be further described with reference to the accompanying figures 1-4 and the specific embodiments. It should be emphasized that the following description is merely exemplary in nature and is not intended to limit the scope of the invention or its application. The background of the present invention may contain background information related to the problem or environment of the present invention and does not necessarily describe the prior art. Accordingly, the inclusion in the background section is not an admission of prior art by the applicant.

In the prior art, a method for manufacturing a chip inductor shown in fig. 1 includes: a coil 37 is formed by winding a conductor around a core leg 33 of a magnetic core having a core leg 33, an upper end 31 and a lower end 34, wherein the lower end 34 of the magnetic core has two recesses 35, the recesses 35 are plated with a metal (e.g., silver), and two ends 36 of the coil 37 are soldered to the two recesses 35 plated with the metal, respectively. Finally, magnetic glue 32 is applied between the upper end 31 and the lower end 34 to form a closed magnetic circuit inductor. In the prior art, a method for manufacturing a chip inductor shown in fig. 2 is as follows: a magnetic core is provided, the magnetic core is provided with a first surface 41 and a second surface 42 which are opposite, the first surface 41 is provided with a bulge 410, and the second surface 42 is provided with a silver plating part 420. The coil 44 is formed by winding the wire around the protrusion 410 (or the coil can be preformed, and directly sleeved), and the two ends 43 of the coil 44 are respectively welded to the silver-plated portions 420. And finally, filling the magnetic solid mixture into the product and forming to form the closed magnetic circuit inductor. The structure and the manufacturing method of the two chip inductors inevitably need to perform welding treatment on the tail end of the coil, and when the height value of the inductor is reduced to be less than 0.8mm, the end part welded with the wire in the magnetic core needs to be correspondingly made to be very thin, so that the strength of the welded end part is reduced, and the strength required by welding is difficult to meet, therefore, the wire is extremely easy to break in the welding treatment process, the defective rate is too high, and batch production is basically impossible. In addition, as can be seen from fig. 1 and 2, both of the structures are such that the ends of the wire penetrate the welding portion of the magnetic core, which further weakens the strength. Furthermore, when a chip high-frequency inductor is to be manufactured, the end of the wire penetrating through the core is also bent, which more easily causes the corresponding portion of the core to break. In view of this, the present invention provides a structural design that can provide sufficient welding strength for the magnetic core welding position, and can further satisfy the bending process for manufacturing the chip type high frequency inductor, thereby avoiding the magnetic core from cracking.

Example one

A chip high-frequency inductor with an L value (7.9 MHz) of 4.7 muH adopts a closed magnetic circuit structure capable of improving inductance, and comprises a magnetic core 10 and a coil package 20, wherein the magnetic core 10 comprises a central column 11 and two side columns (12, 13) positioned at two ends of the central column 11 as shown in figures 3A and 3B, and electrodes (120, 130) are arranged on the bottom surfaces of the side columns (12, 13). The main component of the magnetic core 10 is Ni — Zn ferrite, and the length × width × height of the magnetic core 10 may be 1.55mm × 0.90mm × 0.90 mm. The center pillar 11 may be a rectangular parallelepiped, and the cross section of the center pillar 11 is 0.5mm × 0.5mm, and the length is 0.85 mm. The electrodes (120, 130) are rectangular or nearly rectangular in shape, with a length x width of 0.90mm x 0.35 mm. The coil 20 is preferably made of copper wire.

As shown in fig. 3B, the coil 20 is wound around the center pillar 11, and two ends (21, 22) of the coil 20 are respectively fixed on the bottom surfaces of the electrodes (120, 130) to form patch terminals. Two tip (21, 22) of solenoid 20 certainly to being located respectively after center pillar 11 is drawn forth both ends about center pillar 11 the face of keeping away from the center pillar of side post (12, 13) extends to one section portion of bending (210, 220) has respectively, bend (210, 220) with the bottom of side pillar (12, 13) the bottom surface laminating and the welding of electrode (120, 130) are in the same place, and this structure need not the tip of solenoid 20 runs through the welding position of magnetic core to can avoid causing the influence to welding strength. Preferably, the bending part (210, 220) extends from one side of the bottom surface of the electrode (120, 130) to the other opposite side, i.e., there is as much contact as possible between the two. The welding preferably adopts a hot-press welding mode.

The back of the patch type high-frequency inductor is solidified with magnetic glue 30 which can form a closed magnetic circuit, so that a closed magnetic circuit structure required by a product is formed. The back of the chip type high-frequency inductor refers to a part of the high-frequency inductor far away from the chip terminal. Preferably, the cured magnetic glue 30 at the top surface of the back of the high frequency inductor is a flat surface to facilitate SMT pick up operations. In addition, the closed magnetic circuit structure may be formed by adhering a mixture of a powdery magnetic material and a powdery adhesive agent that can form a closed magnetic circuit to the back of the chip-type high-frequency inductor, or by covering the back of the high-frequency inductor with a magnetic cover that can form a closed magnetic circuit. The closed magnetic circuit structure does not need to thin any part of the magnetic core, so that the strength of the magnet cannot be changed, namely, a necessary closed magnetic circuit can be formed on the premise of not changing the strength of the magnet, and the problem of magnet breakage caused by thinning of relevant parts of the magnet in the prior art is solved.

The magnetic glue is glue containing magnetic powder and used for improving the inductance of a product, so that the defect that the inductance of a small-size patch type high-frequency inductor cannot be very large can be overcome. The magnetic glue can be prepared into different magnetic powder proportions according to actual requirements, so that the magnetic glue with different magnetic conductivities is formed.

It should be noted that the core structure of the present invention is not limited thereto, and other structures are also possible, such as the core shown in fig. 4A and 4B, which is generally called U-shaped.

Example two

A manufacturing method of a patch type high-frequency inductor is used for preparing the patch type high-frequency inductor, and comprises the following steps:

firstly, a winding end is led out from a side column at one end of a magnetic core middle column, then a coil is formed by winding on the magnetic core middle column, the tail end of the coil is hung on the side column at the other end of the magnetic core middle column, then the winding end and the tail end of the coil are respectively fixed on two electrodes on the bottom surfaces of the side columns to form patch terminals, and finally a closed magnetic circuit structure is formed at the back of the patch type high-frequency inductor. The forming of the closed magnetic circuit structure can be realized by coating magnetic glue, bonding a mixture of a powdery magnetic material and a powdery adhesive on the back of the patch type high-frequency inductor or coating a magnetic covering.

In this embodiment, the electrodes on the bottom surfaces of the side pillars are pre-arranged to improve the production efficiency, but not limited thereto, and the electrodes on the bottom surfaces of the side pillars may be arranged before or after the winding to form the coil. In addition, when the coil is formed by winding on the central column of the magnetic core, the number of turns of the winding can be properly adjusted within a certain range according to the electrical property requirement of the inductor, and the manufacturing method of the embodiment can be conveniently realized.

The method for forming the closed magnetic circuit structure by coating the magnetic glue on the back of the surface mount type high-frequency inductor comprises the following steps: and pressing the back of the semi-finished product surface mount type high-frequency inductor with the surface mount terminal into a cavity filled with magnetic glue, and curing the magnetic glue after the magnetic glue reaches a preset height, thereby finishing coating. The preset height is the depth of the semi-finished high-frequency inductor immersed in the magnetic glue and is determined according to the size requirement of inductance. The bottom surface of the cavity is a plane or a smooth cambered surface, so that the top surface of the cured magnetic glue has a plane convenient for SMT absorption operation.

The manufacturing method of the embodiment can manufacture the high-frequency inductor product with the size as in the first embodiment, can meet the requirement of large inductance, can avoid the problem that the side column welding part of the magnetic core is broken in the hot-press welding link, solves the problem of high defective rate when the product is processed, and is suitable for batch production of the product.

EXAMPLE III

A manufacturing method of a patch type high-frequency inductor is used for preparing the patch type high-frequency inductor, and comprises the following steps:

firstly, winding a coil on a magnetic core middle column, and then respectively hanging two tail ends of the coil on side columns at two ends of the magnetic core middle column; electrodes are respectively arranged on the bottom surfaces of the two side columns, and two tail ends of the coil are respectively welded and fixed on the bottom surfaces of the electrodes to form patch terminals; and finally, forming a closed magnetic circuit structure on the back of the patch type high-frequency inductor. Other links such as the manner of forming the closed magnetic structure are the same as those in the foregoing embodiments, and are not described again.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several equivalent substitutions or obvious modifications can be made without departing from the spirit of the invention, and all the properties or uses are considered to be within the scope of the invention.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "preferred embodiments," "an example," "a specific example," or "some examples" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the claims.