A surface-mounted common-mode inductor with a small-size plastic-encapsulated octagonal structure and a manufacturing method thereof

Abstract

The present invention discloses a surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure and a manufacturing method thereof, which includes a magnetic ring, enameled wire, a plastic shell and a plastic base. A circular groove is provided on the upper end surface, and four inner electrodes are arranged at circumferential intervals. The enameled wire is wound around the magnetic ring to form a winding, and the winding is fixedly connected in the circular groove, and the end of the enameled wire is connected to the inner electrode. The plastic shell is covered on the plastic base, and the four inner electrodes are embedded on the plastic base and are evenly distributed at circumferential intervals along it, and are electrically connected to four outer electrodes embedded in the plastic base. After the outer ends of the four outer electrodes extend out of the plastic base, they are bent and closely attached to the bottom surface of the plastic base.

Description

Technical Field

[0001] The present invention relates to a surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure and a manufacturing method thereof, belonging to the technical field of surface-mounted common-mode inductors. Background Art

[0002] The usual manufacturing method of a common-mode inductor is to directly wind enameled wire on various magnetic material magnetic rings, and the head and tail wires of the wound enameled wire are straightened and directly formed into lead-out ends for welding to construct a plug-in structure common-mode inductor. In recent years, the miniaturization and high-reliability technologies of electronic devices have become more and more prominent, and the performance requirements of electrical and electronic devices for anti-electromagnetic interference have also become more and more stringent. To avoid the parasitic parameter coupling of the too-long pins of the plug-in structure common-mode inductor into the circuit and cause new interference, more and more electrical and electronic devices require a surface-mounted common-mode inductor. In addition, although the bottom of some common-mode inductors can meet the surface-mounting requirements, because the exposed magnetic ring surface cannot form an effective solid plane, the automatic placement machine cannot suck the common-mode inductor, and the mass automatic placement requirements cannot be realized. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: to provide a surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure and a manufacturing method thereof to solve the technical problems existing in the prior art.

[0004] The technical solution adopted by the present invention is: a surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure, including a magnetic ring, enameled wire, a plastic shell and a plastic base. A circular groove is provided on the upper end surface, and four inner electrodes are arranged at circumferential intervals. The enameled wire is wound around the magnetic ring to form a winding, the winding is fixedly connected in the circular groove, and the end of the enameled wire is connected to the inner electrode. The plastic shell covers the plastic base, the four inner electrodes are embedded in the plastic base and are evenly distributed at circumferential intervals along it, and are electrically connected to four outer electrodes embedded in the plastic base. The outer ends of the four outer electrodes extend out of the plastic base and then bend and cling to the bottom surface of the plastic base.

[0005] Preferably, the above-mentioned winding is fixedly bonded to the plastic base by an adhesive.

[0006] Preferably, the above-mentioned magnetic ring is an annular magnetic ring, and the annular magnetic ring is selected from nickel-zinc ferrite, manganese-zinc ferrite and amorphous magnetic ring, and the annular magnetic ring is subjected to a coating treatment.

[0007] Preferably, after the above-mentioned plastic shell covers the winding, an adhesive is used to fixedly bond both between the winding and the plastic shell and between the plastic shell and the plastic base.

[0008] Preferably, the above-mentioned plastic base and plastic shell are octagonal. Four inner electrodes are symmetrically and vertically arranged on four side end faces of the plastic base. An inverted U-shaped opening is arranged on one side of the plastic shell corresponding to the four inner electrodes.

[0009] Preferably, a groove is arranged on the edge of the upper end face of the above-mentioned plastic base.

[0010] Preferably, L-shaped clamping platforms are arranged on the inner sides of the lower ends of two pairs of opposite sides of the above-mentioned plastic shell. The L-shaped clamping platforms are clamped to the two side end faces of the plastic base.

[0011] A preparation method of a small-sized surface-mounted common-mode inductor with a plastic-encapsulated octagonal structure, the method comprising the following steps:

[0012] (1) Wind an enameled wire with a double-layer paint film and a circular copper wire diameter of 0.3 mm to 0.6 mm around a magnetic ring. Fix the magnetic ring on a fixture. Use a crochet needle to thread the enameled wire. When in the double-wire parallel winding mode, make the enameled wires together. Fix the starting end of the enameled wire. The crochet needle pulls the together enameled wires to wind one week clockwise inside and outside the magnetic ring, leaving the end of the enameled wire, and complete the production of two windings; when in the single-wire separate winding mode, fix the starting end of a single group of enameled wire, take half a turn of the magnetic ring, the crochet needle pulls the enameled wire to wind half a turn clockwise inside and outside the magnetic ring, leaving the end of the enameled wire, and complete the production of the first winding. Fix the magnetic ring again, and use the crochet needle to wind half a turn counterclockwise inside and outside the magnetic ring for the remaining half turn of the magnetic ring, leaving the end of the enameled wire, and complete the production of the other winding;

[0013] (2) Wind the four wire ends of the winding made in step (1) around 4 inner electrodes on the plastic base for one turn respectively, and remove the excess wire heads; Next, dip the four wire ends wound around the inner electrodes in tin, remove the paint film, and weld the ends of the wire ends;

[0014] (3) Dot silicone adhesive in the gap between the plastic base and the center of the winding in step (2), and dot a circle of epoxy resin adhesive between the four sides of the plastic base and the outside of the winding; At the same time, dot epoxy resin adhesive at the center of the bottom of the plastic shell, and then invert the plastic shell with the starting foot circular marking point on the shell surface aligned with the starting end of the first winding on the winding and plastic base made in step (2);

[0015] (4) Place the product in step (3) with the plastic shell facing up in a baking tray for baking and curing. The baking temperature is 130°C ± 10°C, and the baking time is 90 min ± 10 min.

[0016] The beneficial effects of the present invention: Compared with the prior art, the effects of the present invention are as follows:

[0017] (1)The present invention is proposed based on miniaturized and highly reliable surface mount technology. Most traditional common mode inductors are directly wound on magnetic rings. Due to the irregular and uneven surface of the windings, pick-and-place machines cannot pick them up, resulting in the inability of pick-and-place machines to perform surface mounting operations;

[0018] (2)For the common mode inductor proposed by the present invention, a regular and flat plane is formed on the product surface by using a plastic shell, which can ensure that the pick-and-place machine can automatically pick up the product and meet the requirements of large-scale automated mounting. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a three-dimensional structural schematic diagram of the present invention;

[0020] Figure 2 is a top view structural schematic diagram of the present invention;

[0021] Figure 3 is a bottom view structural schematic diagram of the present invention;

[0022] Figure 4 is a winding structure schematic diagram;

[0023] Figure 5 is a three-dimensional structural schematic diagram of the plastic base;

[0024] Figure 6 is a top view structural schematic diagram after the winding is installed on the plastic base;

[0025] Figure 7 is a side view structural schematic diagram of the plastic shell;

[0026] Figure 8 is a three-dimensional structural schematic diagram of the plastic base. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The present invention will be further introduced below in conjunction with the accompanying drawings and specific embodiments.

[0028] Embodiment 1: As Figures 1-8As shown in the figure, a surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure includes a magnetic ring 1, an enameled wire 2, a plastic housing 3, and a plastic base 4. A circular groove 5 is provided on the upper end surface, and four inner electrodes 6 are circumferentially arranged at intervals. The enameled wire 2 is wound around the magnetic ring 1 to form a winding. The winding is fixedly connected in the circular groove 5, and the end of the enameled wire 2 is connected to the inner electrode 6. The plastic housing 3 is covered on the plastic base 4. The four inner electrodes 6 are embedded in the plastic base 4 and are evenly distributed along its circumference, and are electrically connected to four outer electrodes 10 embedded in the plastic base 4. The outer ends of the four outer electrodes 10 extend out from the plastic base 4 and are bent to closely adhere to the bottom surface of the plastic base 4 to provide a surface-mounted structure for the common-mode inductor. The outer ends of the four outer electrodes 10 continue to extend and bend to closely adhere to the side end surface of the plastic base 4 to play a role in stabilizing the outer electrodes. The four outer electrodes are distributed on two opposite sides of the octagonal plastic base, with two symmetrically on each side. The enameled wire is an enameled round copper wire, and two symmetric windings or co-directional windings are wound on the annular magnetic ring. The ends of the windings are wound around the inner electrodes.

[0029] The ends of the windings wound on the inner electrodes are firmly welded after removing the paint film by high-temperature treatment.

[0030] Preferably, an adhesive is used to adhesively fix the winding and the plastic base 4, and the adhesion is firm and stable.

[0031] Preferably, the magnetic ring 1 is a ring-shaped magnetic ring. To obtain the required electrical properties, the ring-shaped magnetic ring is selected from nickel-zinc ferrite, manganese-zinc ferrite, and amorphous magnetic ring, and the magnetic ring is subjected to a coating treatment.

[0032] Preferably, after the plastic housing 3 covers the winding, an adhesive is used to adhesively fix both between the winding and the plastic housing 3 and between the plastic housing 3 and the plastic base 4, and the adhesion is firm and stable.

[0033] Preferably, the plastic base 4 and the plastic housing 3 are octagonal. The four inner electrodes 6 are symmetrically and vertically arranged on four side end faces of the plastic base 4, vertically arranged, with outer connections and surface mounting at the edges. An inverted U-shaped opening 8 is provided on one side of the plastic housing 3 corresponding to the four inner electrodes 6, and the edge windings are led to the inner electrodes to avoid blocking the ends of the windings.

[0034] Preferably, a groove 7 is provided at the edge of the upper end surface of the plastic base 4 to increase the adhesive contact surface and make the adhesion more reliable.

[0035] Preferably, two opposite sides of the plastic housing 3 are cantilever plates, and an L-shaped clamping platform 9 is provided on the inner side of the lower end of the cantilever plates. The L-shaped clamping platform 9 is clamped to the two side end faces of the plastic base 4, which is convenient for the plastic housing 3 to be quickly docked to the plastic base, improves the installation efficiency, and has higher connection stability and reliability.

[0036] Embodiment 2: A preparation method of a surface-mounted common-mode inductor with a small-size plastic-encapsulated octagonal structure, the method comprising the following steps:

[0037] (1) Wind an enameled wire of double-layer paint film round copper with a wire diameter of 0.3 mm to 0.6 mm on a magnetic ring, fix the magnetic ring on a fixture, use a crochet hook to thread the enameled wire, when in the double-wire parallel winding mode, make the enameled wires together, fix the starting end of the enameled wire, use the crochet hook to pull the enameled wires together and wind them clockwise around the inside and outside of the magnetic ring for one week, leave the end of the enameled wire, and complete the production of two windings; when in the single-wire separate winding mode, fix the starting end of a single group of enameled wire, take half a circumference of the magnetic ring, use the crochet hook to pull the enameled wire and wind it clockwise around the inside and outside of the magnetic ring for half a week, leave the end of the enameled wire, and complete the production of the first winding, re-fix the magnetic ring, and use the crochet hook to wind the enameled wire counterclockwise around the inside and outside of the magnetic ring for half a week on the remaining half circumference of the magnetic ring, leave the end of the enameled wire, and complete the production of the other winding;

[0038] (2) Wind the four wire ends of the winding made in step (1) around 4 inner electrodes on a plastic base for one circle respectively, and remove the excess wire ends; next, dip the four wire ends wound around the inner electrodes in tin, remove the paint film, and weld the ends of the wire ends well;

[0039] (3) Dot silicone adhesive in the gap between the plastic base and the center of the winding in step (2), and dot a circle of epoxy resin adhesive between the four sides of the plastic base and the outside of the winding; at the same time, dot epoxy resin adhesive at the center of the bottom of the plastic shell, and then place the plastic shell with the starting foot circular marking point on the outer shell surface facing the starting end of the first winding and buckle it on the winding and the plastic base made in step (2);

[0040] (4) Place the product in step (3) with the plastic shell facing up in a baking tray for baking and curing, the baking temperature is 130°C ± 10°C, and the baking time is 90 min ± 10 min.

[0041] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claimed rights.

Claims

1. A surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure, characterized in that: It includes a magnetic ring (1), enameled wire (2), a plastic shell (3) and a plastic base (4). A circular groove (5) is provided on the upper end surface, and four inner electrodes (6) are arranged at circumferential intervals. The enameled wire (2) is wound around the magnetic ring (1) to form a winding. The winding is fixedly connected in the circular groove (5), and the ends of the enameled wire (2) are connected to the inner electrodes (6). The plastic shell (3) covers the plastic base (4). The four inner electrodes (6) are embedded in the plastic base (4) and are evenly distributed at circumferential intervals along it, and are electrically connected to four outer electrodes (10) embedded in the plastic base (4). The outer ends of the four outer electrodes (10) extend out from the plastic base (4) and then bend and stick tightly to the bottom surface of the plastic base (4); The plastic base (4) and the plastic shell (3) are octagonal; The preparation method of the surface-mounted common-mode inductor with the small-sized plastic-encapsulated octagonal structure includes the following steps: (1) Wind the enameled wire of double-layer paint film round copper with a wire diameter of 0.3 mm to 0.6 mm around the magnetic ring. Fix the magnetic ring on the fixture. Use a crochet needle to thread the enameled wire. When in the double-wire parallel winding mode, make the enameled wires together. Fix the starting end of the enameled wire. The crochet needle pulls the together enameled wires to wind around the inside and outside of the magnetic ring clockwise for one week, leaving the end of the enameled wire, and complete the production of two windings; When in the single-wire separate winding mode, fix the starting end of the single-group enameled wire. Take half a week of the magnetic ring. The crochet needle pulls the enameled wire to wind around the inside and outside of the magnetic ring clockwise for half a week, leaving the end of the enameled wire, and complete the production of the first winding. Fix the magnetic ring again. Use the crochet needle to wind around the inside and outside of the magnetic ring counterclockwise for half a week on the remaining half of the magnetic ring, leaving the end of the enameled wire, and complete the production of the other winding; (2) Wind the four wire ends of the winding made in step (1) around the 4 inner electrodes on the plastic base for one circle respectively, and remove the excess wire heads; Immerse the four wire ends wound on the inner electrodes in tin, remove the paint film, and weld the ends of the wire ends; (3) Dot silicone adhesive in the gap between the plastic base and the winding center in step (2), and dot a circle of epoxy resin adhesive between the four sides of the plastic base and the outside of the winding; At the same time, dot epoxy resin adhesive at the center of the bottom of the plastic shell, and then place the plastic shell with the starting foot circular mark point on the outer shell surface facing the starting end of the first winding and buckle it on the winding and plastic base made in step (2); (4) Place the product in step (3) with the plastic shell facing up in a baking tray for baking and curing. The baking temperature is 130°C ± 10°C, and the baking time is 90 min ± 10 min.

2. A surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure according to claim 1, characterized in that: The four inner electrodes (6) are respectively symmetrically and vertically arranged on the four side end faces of the plastic base (4), and an inverted U-shaped opening (8) is provided on one side of the plastic shell (3) corresponding to the four inner electrodes (6).

3. A surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure according to claim 2, characterized in that: A groove (7) is provided at the edge of the upper end surface of the plastic base (4).

4. A surface-mounted common-mode inductor with a small-sized plastic-encapsulated octagonal structure according to claim 2, characterized in that: L-shaped clamping platforms (9) are arranged on the inner sides of the lower ends of two opposite sides of the plastic housing (3), and the L-shaped clamping platforms (9) are clamped to the two side end faces of the plastic base (4).

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