Tandem type high-inductance mould pressing inductor and forming method thereof

Abstract

The invention relates to a series type high-inductance mould pressing inductor and a forming method thereof.The mould pressing inductor comprises a metal wire and a plurality of soft magnetic metal blocks, the soft magnetic metal blocks are arranged on the metal wire at intervals, the multiple soft magnetic metal blocks are attached and arranged side by side by bending the metal wire, and the side faces of the adjacent soft magnetic metal blocks are fixedly connected through mucilage glue; the two ends of the metal wire are located at the bottom of the soft magnetic metal block and serve as pins or are welded with pins. Or the pins are positioned on the side surfaces of the soft magnetic metal blocks, are bent to the bottoms of the soft magnetic metal blocks and are used as pins; or the pins are positioned on the side surface of the soft magnetic metal block and are welded with the pins, and the pins are bent to the bottom of the soft magnetic metal block. The multiple inductor units are connected in series through the same metal wire, the magnetic flux density is improved exponentially, and therefore the purpose of improving the induction value is achieved; and meanwhile, only one metal wire is arranged in each soft magnetic metal block, so that high-temperature heat treatment can be adopted, and the integrally-formed co-fired mould pressing inductor with high inductance value and low loss can be manufactured.

Description

Technical Field

[0001] The present application relates to the technical field of inductor processing, and in particular to a series high-inductance molded inductor and a molding method thereof. Background Art

[0002] The inductance of one-piece molded inductors can be greatly improved after high-temperature heat treatment. From a microscopic analysis, on the one hand, the internal atomic activity of metallic soft magnetic materials is enhanced at high temperatures, which accelerates the release of internal stress, reduces coercive force, and increases density and magnetic permeability; on the other hand, high-temperature heat treatment promotes grain growth and recrystallization, improves the organizational structure of the material, and thus improves its magnetic and mechanical properties.

[0003] The above is to improve the inductance from the perspective of metal soft magnetic powder. The other is to start from the internal coil of the product. Increasing the number of windings is currently one of the main ways to improve the inductance of one-piece molded inductors. However, the enamel film has limited temperature resistance. It will carbonize in a high temperature environment above 300°C, causing a short circuit between the coil windings and leading to inductance failure. Therefore, the winding coil is not suitable for high-temperature heat treatment processes. How to maintain the effectiveness of the inductor while ensuring high inductance and low loss has become a difficult problem in the industry.

[0004] The Chinese patent application with publication number CN111243814A discloses a copper sheet embedded soft magnetic powder core inductor and a preparation method thereof, wherein a layer of copper sheet is embedded inside the soft magnetic powder core inductor, the surface of the copper sheet is covered with soft magnetic material, the interface between the soft magnetic material and the copper sheet contains insulating resin material, the soft material is symmetrically distributed on the two sides of the copper sheet, the pressing is annealed in an inert atmosphere, and the areas at both ends of the copper sheet not covered by the soft magnetic material are bent to obtain the copper sheet embedded soft magnetic powder core inductor. The copper sheet embedded soft magnetic powder core inductor has the characteristics of high density, high magnetic core permeability, high inductance, high saturation magnetic flux density, small volume and less leakage magnetic field. It can replace the ferrite inductor of the same inductance and be applied to the low-voltage DC / DC converter circuit, which can obtain the same or higher efficiency, and the volume of the inductor can be reduced by more than half.

[0005] A Chinese patent application with publication number CN112435844A discloses an integrated co-fired inductor and a preparation method thereof. The preparation method comprises: filling a mold cavity with magnetic powder, burying at least one wire in the magnetic powder, with both ends of the wire extending out of the mold cavity, followed by sequential molding and heat treatment to obtain a magnetic core, and bending and tinning the wire extending out of the magnetic core to obtain the co-fired inductor. The inductor obtained by this scheme avoids the assembly process of too many components, and is heat treated after integrated molding to fully release stress and reduce the hysteresis loss of the material.

[0006] The Chinese patent application with publication number CN115938718A discloses a plug-in integrated co-fired inductor and a preparation method thereof. The inductor consists of two parts: a soft magnetic metal powder and an inverted U-shaped copper conductor. The two ends of the copper conductor extend out of the powder, and the rest is buried in the powder. The steps of the inductor preparation method are: (1) pretreatment of the soft magnetic metal powder; (2) burying the copper conductor in the treated metal powder and pressing it under a high pressure of 1700-2100MPa; (3) gradient annealing the product obtained in step (2) using a reducing atmosphere; (4) impregnating the annealed product in a resin solution, washing and baking to obtain a plug-in integrated co-fired inductor. The inductor not only has the advantages of high magnetic shielding performance, high mechanization of production, and high performance uniformity of an integrated inductor, but also has the advantages of high density and low loss of magnetic powder core materials.

[0007] The above three methods all use high temperature technology to maximize the inductance value from the powder, but the product uses a single copper wire or a single copper sheet as a conductor. Although it effectively avoids the problem of carbonization short circuit of the enamel film, the induced magnetic flux density is limited. This patent invents a structural design and production method of a series high-inductance molded inductor, which can maximize the magnetic flux density by connecting n inductors in series, thereby achieving the purpose of increasing the inductance. Summary of the invention

[0008] In order to solve the technical problem of how to maintain the effectiveness of the inductor in a high-temperature heat treatment process while ensuring high inductance and low loss, the present invention provides a series high-inductance molded inductor and a molding method thereof.

[0009] On the one hand, the technical solution provided by the present application is as follows: a series high-inductance molded inductor, comprising a metal conductor and a plurality of soft magnetic metal blocks, wherein the soft magnetic metal blocks are arranged at intervals on the metal conductor, and the plurality of soft magnetic metal blocks are attached and arranged in a row by bending the metal conductor, and the sides of adjacent soft magnetic metal blocks are fixedly connected by adhesive, and the two ends of the metal conductor are located at the bottom of the soft magnetic metal block and serve as pins or are welded with pins; or the two ends of the metal conductor are located at the side of the soft magnetic metal block and are bent to the bottom of the soft magnetic metal block and serve as pins; or the two ends of the metal conductor are located at the side of the soft magnetic metal block and are welded with pins, and the pins are bent to the bottom of the soft magnetic metal block.

[0010] By adopting the above technical solution, the present application adopts the structure of the one-piece co-fired inductor in the prior art, but adopts a series structure, using the same metal wire to connect multiple inductor units in series, thereby increasing the magnetic flux density by N times, thereby achieving the purpose of increasing the inductance; at the same time, since there is only one metal wire inside each soft magnetic metal block, high-temperature heat treatment can be used to make a high-inductance, low-loss one-piece co-fired molded inductor, without worrying about the carbonization of the enamel film in a high-temperature environment, causing a short circuit between the coil windings, and leading to technical problems such as inductor failure. The sides of adjacent soft magnetic metal blocks are fixedly connected by adhesive to avoid vibration and noise problems. The length, width and height dimensions of the molded inductor products of this application can be flexibly selected and adjusted to meet the complex and diverse needs of customers.

[0011] Preferably, the plurality of soft magnetic metal blocks are attached to each other and arranged in a straight line, the metal wire enters from the bottom surface of the first soft magnetic metal block, passes through the top surface of the first soft magnetic metal block, enters from the top surface of the second soft magnetic metal block after bending, passes through the bottom surface of the second soft magnetic metal block, and so on, and finally passes through the bottom surface of the Nth soft magnetic metal block, and the two ends of the metal wire are used as pins or are welded with pins.

[0012] Preferably, the plurality of soft magnetic metal blocks are arranged in a straight line and in a row, the metal wire enters from the side of the first soft magnetic metal block, passes through the other side opposite to the first soft magnetic metal block, enters from the side of the second soft magnetic metal block after bending, passes through the other side opposite to the second soft magnetic metal block, and so on, and finally passes through the side of the Nth soft magnetic metal block, and the two ends of the metal wire are bent to the bottom of the soft magnetic metal block to serve as pins or are welded with pins.

[0013] Preferably, the molded inductor further comprises an insulating top cover, and the insulating top cover and the top of the soft magnetic metal block are fixedly connected by glue; or the top of the soft magnetic metal block is coated with glue so that the common top of the multiple soft magnetic metal blocks is flat and has no gaps.

[0014] Preferably, the metal wire is copper foil, copper sheet, flat copper wire, round copper wire, enameled flat copper wire or enameled round copper wire.

[0015] Preferably, the soft magnetic metal block is in the shape of a cuboid, and the metal wire is centrally arranged in the soft magnetic metal block.

[0016] Preferably, two ends of the metal wire are flattened to form pins; or the two ends are connected with pins by spot welding.

[0017] Preferably, the bent metal wires between the multiple soft magnetic metal blocks are fixed on the soft magnetic metal blocks by adhesive.

[0018] On the other hand, the present application also provides the following technical solution: a molding method of the above-mentioned series high-inductance molded inductor, comprising the following steps: S1, placing a metal wire in a molding die, wherein the molding die has at least two cavities; S2, filling the soft magnetic metal powder into the cavity and pressing it into shape; S3, high temperature heat treatment; S4, bending the metal wire so that the multiple soft magnetic metal blocks are attached to each other and arranged in a row, and the sides of adjacent soft magnetic metal blocks are fixedly connected by adhesive; S5, forming the two ends of the metal wire into pins, or shaping the pins welded to the two ends of the metal wire.

[0019] Preferably, in step S3, the temperature of the high temperature heat treatment is 650°C to 850°C.

[0020] In summary, the present application includes at least one of the following beneficial technical effects: 1. This application adopts a series structure, using the same metal wire to connect multiple inductance units in series, which increases the magnetic flux density exponentially, thereby achieving the purpose of increasing the inductance; 2. Since there is only one metal wire inside each soft magnetic metal block, high-temperature heat treatment can be used to make a high-inductance, low-loss one-piece co-fired molded inductor. There is no need to worry about the enamel film being carbonized in a high-temperature environment, causing a short circuit between the coil windings and leading to technical problems such as inductor failure; 3. The sides of adjacent soft magnetic metal blocks are fixed and connected by adhesive to avoid vibration and noise problems; 4. The length, width and height dimensions of the molded inductor product of this application can be flexibly selected and adjusted to meet the complex and diverse needs of customers. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a three-dimensional diagram of the molded inductor described in Example 1 of the present application; Figure 2 is a perspective view of the molded inductor described in Example 1 of the present application; Figure 3 is a schematic diagram of a half-section structure of the molded inductor described in Example 1 of the present application; Figure 4 is an exploded perspective view of the molded inductor described in Example 1 of the present application; Figure 5 It is a schematic diagram of forming a soft magnetic metal block on a metal conductor in the forming method of the molded inductor described in the first embodiment of the present application; Figure 6 It is a schematic diagram of the soft magnetic metal blocks after being bonded and arranged in a row in the molding method of the molded inductor described in the first embodiment of the present application; Figure 7 It is a schematic diagram of bending the end of a metal wire into a pin and assembling an insulating top cover in the molding method of the molded inductor described in the first embodiment of the present application; Figure 8 is a perspective view of the molded inductor described in the second embodiment of the present application; Fig. 9 is a front perspective view of the molded inductor described in Example 3 of the present application; Fig.10 is a rear perspective view of the molded inductor described in the third embodiment of the present application; Fig.11 It is a schematic diagram of forming a soft magnetic metal block on a metal conductor in the forming method of the molded inductor described in the third embodiment of the present application; Fig.12 is a perspective view of the molded inductor described in the fourth embodiment of the present application; Fig.13 is a rear perspective view of the molded inductor described in Example 5 of the present application; Fig.14 It is a schematic diagram of forming a soft magnetic metal block on a metal conductor in the forming method of the molded inductor described in Example 5 of the present application.

[0022] Explanation of the reference numerals: 1. metal wire; 11. terminal; 2. soft magnetic metal block; 3. adhesive; 4. pin; 5. insulating top cover. DETAILED DESCRIPTION

[0023] The following is combined with Figures 1 to 14 This application is described in further detail. Embodiment 1:

[0024] Reference Figures 1 to 4 The embodiment of the present application discloses a series high-inductance molded inductor, including a metal wire 1 and a plurality of soft magnetic metal blocks 2, wherein the soft magnetic metal blocks 2 are arranged on the metal wire 1 at intervals, and the metal wire 1 is bent so that the plurality of soft magnetic metal blocks 2 are attached to each other and arranged in a row, and the sides of adjacent soft magnetic metal blocks 2 are fixedly connected by adhesive 3, and the two ends of the metal wire 1 are located at the bottom of the soft magnetic metal block 2 and are bent outward to fit the bottom of the soft magnetic metal block 2, and serve as SMD pins 4 of the molded inductor.

[0025] In this embodiment, the plurality of soft magnetic metal blocks 2 are attached and arranged in a straight line, the metal wire 1 enters from the bottom surface of the first soft magnetic metal block 2, passes through the top surface of the first soft magnetic metal block 2, enters from the top surface of the second soft magnetic metal block 2 after bending, and passes through the bottom surface of the second soft magnetic metal block 2, and the two ends of the metal wire 1 are used as pins 4. (If the two ends are not bent, they can be used as the pins of the direct plug-in (DIP) inductor, and if the two ends are bent, the pins 4 of the surface mount (SMD) inductor are formed).

[0026] If there are more than two soft magnetic metal blocks, the above method can be used to pierce through the bottom surface of the Nth soft magnetic metal block. In this way, the inductance of the molded inductor will increase by three times, four times, or N times.

[0027] In this embodiment, the metal wire 1 is a copper sheet, but it can also be in other forms, such as copper foil, flat copper wire, round copper wire, enameled flat copper wire or enameled round copper wire, etc., and the material is not limited to copper.

[0028] In this embodiment, the soft magnetic metal block 2 is in the shape of a cuboid, and the metal wire 1 is centrally arranged in the soft magnetic metal block 2 , so as to facilitate the soft magnetic metal blocks 2 to be attached and arranged in parallel and fixed with the adhesive 3 .

[0029] In this embodiment, the molded inductor further includes an insulating top cover 5, and the insulating top cover 5 and the top of the soft magnetic metal block 2 are fixedly connected by adhesive 3. Since the metal wires 1 between adjacent soft magnetic metal blocks 2 are located outside the soft magnetic metal blocks 2, the top of the soft magnetic metal blocks 2 will be uneven. In this embodiment, the insulating top cover 5 is added because the top surface of the insulating top cover 5 is flat, and the main purpose is to facilitate the SMT suction operation of the client.

[0030] In addition, in the present application, the top of the soft magnetic metal block can also be coated with glue to make the common top of the multiple soft magnetic metal blocks flat and gap-free, which can also facilitate the client's SMT suction operation. This application is not limited to the above form, as long as the central position of the top can be guaranteed to be flat and can be sucked by the suction nozzle.

[0031] In the present application, the bent metal wires 1 between the multiple soft magnetic metal blocks 2 can also be fixed on the soft magnetic metal blocks 2 by means of adhesive 3, for the same reason of avoiding vibration and noise problems.

[0032] The present application adopts the structure of the one-piece co-fired inductor in the prior art, but adopts a series structure, using the same metal wire 1 to connect multiple inductor units in series, thereby increasing the magnetic flux density by N times, thereby achieving the purpose of increasing the inductance; at the same time, since there is only one metal wire 1 inside each soft magnetic metal block 2, high-temperature heat treatment can be used to make a one-piece co-fired molded inductor with high inductance and low loss, without worrying about the carbonization of the enamel film in a high-temperature environment, causing a short circuit between the coil windings, and leading to technical problems such as inductor failure. The sides of adjacent soft magnetic metal blocks 2 are fixedly connected by adhesive 3 to avoid vibration and noise problems. The length, width and height dimensions of the molded inductor product of the present application can be flexibly selected and adjusted to meet the complex and diverse needs of customers.

[0033] The molding method of the series high-inductance molded inductor described above comprises the following steps: S1, placing the metal wire 1 in a forming mold. When the metal wire 1 is relatively soft, both ends should be straightened and tightened. The forming mold has at least two cavities, that is, at least two soft magnetic metal blocks 2 are made on the metal wire 1.

[0034] S2, reference Figure 5 , fill the soft magnetic metal powder into the cavity and press it into shape; high pressure can be used for compression molding here to obtain a compact and dense soft magnetic metal block 2; since the metal wire 1 does not need to be wound into a winding and will not form a multi-turn coil structure, high pressure compression molding will not have a significant impact on the shape of the metal wire 1.

[0035] S3, high temperature heat treatment; the temperature of high temperature heat treatment is preferably 650℃~850℃; the specific temperature selection factors also need to refer to the specific composition of the soft magnetic metal powder actually used. High temperature heat treatment can greatly improve the inductance value. On the one hand, the internal atomic activity of the metal soft magnetic material is enhanced at high temperature, which accelerates the release of internal stress, reduces coercive force, and increases density and magnetic permeability; on the other hand, high temperature heat treatment promotes grain growth and recrystallization, improves the organizational structure of the material, thereby improving its magnetic properties and mechanical properties.

[0036] S4, ref. Figure 6 , bend the metal wire 1, so that multiple soft magnetic metal blocks 2 are arranged in parallel, and the adjacent soft magnetic metal blocks 2 are fixedly connected by adhesive 3. Here, adhesive 3 is preferably insulating adhesive to prevent adjacent soft magnetic metal blocks 2 from contacting and conducting electricity, which affects the inductor unit. In this embodiment, multiple soft magnetic metal blocks 2 are arranged in parallel in a straight line. Of course, other arrangements can also be used, such as multi-row and multi-column forms such as field shapes. The shape of the metal wire 1 should also be adaptively modified to match the folding direction of the soft magnetic metal block 2 (round copper wire basically does not need to consider this issue).

[0037] S5, refer to Figure 7, the two ends 11 of the metal wire 1 are formed into pins 4. In this embodiment, the two ends 11 are bent outward so that the two ends 11 are attached to the bottom surface of the soft magnetic metal block 2 to form SMD pins 4; when the size of the two ends 11 is too large or too small and is not suitable for directly forming pins 4, pins 4 of suitable size can also be welded to the two ends 11 of the metal wire 1. Since the molded inductor of this embodiment also includes an insulating top cover 5, it is also necessary to include a step of sticking the insulating top cover 5 to the top of the soft magnetic metal block 2.

[0038] If there are restrictions on the length and width of the inductor in the actual use scenario of the client, but no restrictions on the height, the structure of this embodiment can be selected to increase the inductance by increasing the height of the soft magnetic metal block 2 and the length of the metal wire 1. In fact, the width of the soft magnetic metal block 2 can be very small, even at the millimeter level. For example, if the inductor product requires a total width of 5mm and no height limit, then five inductor units can be connected in series. The width of each inductor unit (mainly the soft magnetic metal block 2) is limited to about 0.9mm, and the glue bonding thickness is about 0.1mm. Not limited by the size required by the customer, the length, width and height of the inductor product can be flexibly selected and adjusted. Embodiment 2:

[0039] Reference Figure 5 , which is different from the first embodiment, is that the metal conductor 1 is a round copper wire, and copper sheets are welded to the two ends of the round copper wire. Half of the copper sheet is inside the soft magnetic metal block 2, and the other half is outside the soft magnetic metal block 2, and then bent outward to fit the bottom of the soft magnetic metal block 2 to form a pin 4. Because the diameter of the round copper wire is too small and the size is not suitable for being directly used as the pin 4 of the SMD product, a piece of copper sheet is welded at both ends to form the copper sheet into the pin 4. In addition, half of the copper sheet is inside the soft magnetic metal block 2, which is equivalent to being embedded in the soft magnetic metal block 2. The copper sheet has a good fixing effect, and the force is no longer limited to the soldering point. The strength and stability of the pin 4 are better, and the soldering point is generally not damaged when the copper sheet is bent outward.

[0040] In the molding method of the molded inductor of this embodiment, the copper sheet is first welded to the two ends of the round copper wire, and then the soft magnetic metal block 2 is molded. After high-temperature heat treatment, the copper sheet is bent and shaped.

[0041] In this embodiment, the two ends of the metal wire 1 can also be flattened to form copper sheets, and then bent into pins 4. This is also feasible, but the diameter of the metal wire 1 needs to be larger. Other structures and beneficial effects are consistent with Example 1 and will not be repeated here. Embodiment three:

[0042] Reference Fig. 9 and Fig.10, which is different from the first embodiment in that the direction of the metal wire 1 passing in and out is different, and the way the two ends of the metal wire 1 are formed into the pins 4 is also different. Specifically: a plurality of the soft magnetic metal blocks 2 are arranged in a straight line, and the metal wire 1 enters from the side of the first soft magnetic metal block 2, passes through the other side opposite to the first soft magnetic metal block 2, and then enters from the side of the second soft magnetic metal block 2 after bending, and passes through the other side opposite to the second soft magnetic metal block 2. Please refer to the expanded diagram of the molded inductor of this embodiment Fig.11 .

[0043] If there are more than two soft magnetic metal blocks, the above method is followed by analogy, and finally the wire is passed through the side of the Nth soft magnetic metal block. The two ends of the metal wire are bent to the bottom of the soft magnetic metal block and used as pins or welded with pins.

[0044] This embodiment does not need to set an insulating top cover because the top surface of the soft magnetic metal block 2 is flat and will not affect the client SMT suction operation. The application of this embodiment is also very flexible because the metal wires 1 between adjacent soft magnetic metal blocks 2 are located on the side of the soft magnetic metal block 2, and the number of soft magnetic metal blocks 2 can be expanded arbitrarily.

[0045] If there is a limit on the height of the inductor in the actual use scenario of the client, but there is no limit on the length and width, the structure of this embodiment can be selected to increase the length of the metal wire 1 by increasing the number of parallel soft magnetic metal blocks 2 to increase the inductance. For example, if the height of the inductor product is required to be 8mm, and the length and width are not limited, then two or more inductor units can be connected in series, and the height of each inductor unit is limited to about 7.9mm, and the thickness of the bottom pin 4 is about 0.1mm. Other structures and beneficial effects are consistent with those of the first embodiment and will not be repeated here. Embodiment 4:

[0046] Reference Fig.12 , which is different from the third embodiment in that the metal wire 1 is a round copper wire, and copper sheets are welded to the two ends of the round copper wire, a small half of the copper sheet is inside the soft magnetic metal block 2, a large half is exposed from the soft magnetic metal block 2, and then bent outward to fit the bottom of the soft magnetic metal block 2 to form a pin 4. The benefits of welding copper sheets to the two ends of the metal wire 1 have been described in the second embodiment, and will not be repeated here. Embodiment five:

[0047] Reference Fig.13 and Fig.14The difference from the third embodiment is that the number of soft magnetic metal blocks 2 is different. There are three soft magnetic metal blocks in this embodiment. When the soft magnetic metal blocks 2 are odd numbers and even numbers, the directions of the two ends 11 of the metal wire 1 are different and need to be adjusted. In this embodiment, the two ends 11 are biased to the left and the right relative to the middle. After being formed into pins 4, they are basically close to the two diagonal positions of the molded inductor to balance and support the molded inductor. Other structures and beneficial effects are consistent with those of the third embodiment and will not be repeated here.

[0048] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A series high-inductance molded inductor, characterized in that: It comprises a metal wire and a plurality of soft magnetic metal blocks, wherein the soft magnetic metal blocks are arranged at intervals on the metal wire, and the metal wire is bent so that the plurality of soft magnetic metal blocks are attached and arranged in a row, and the sides of adjacent soft magnetic metal blocks are fixedly connected by adhesive, and the two ends of the metal wire are located at the bottom of the soft magnetic metal block and serve as pins or are welded with pins; or the two ends of the metal wire are located at the side of the soft magnetic metal block and are bent to the bottom of the soft magnetic metal block and serve as pins; or the two ends of the metal wire are located at the side of the soft magnetic metal block and are welded with pins, and the pins are bent to the bottom of the soft magnetic metal block.

2. The series high-inductance molded inductor according to claim 1, characterized in that: The multiple soft magnetic metal blocks are attached and arranged in a straight line. The metal wire enters from the bottom surface of the first soft magnetic metal block, passes through the top surface of the first soft magnetic metal block, enters from the top surface of the second soft magnetic metal block after bending, passes through the bottom surface of the second soft magnetic metal block, and so on, and finally passes through the bottom surface of the Nth soft magnetic metal block. The two ends of the metal wire are used as pins or are welded with pins.

3. The series high-inductance molded inductor according to claim 1, characterized in that: The multiple soft magnetic metal blocks are arranged in a straight line and in a row. The metal wire enters from the side of the first soft magnetic metal block, passes through the other side opposite to the first soft magnetic metal block, enters from the side of the second soft magnetic metal block after bending, passes through the other side opposite to the second soft magnetic metal block, and so on, and finally passes through the side of the Nth soft magnetic metal block. The two ends of the metal wire are bent to the bottom of the soft magnetic metal block and used as pins or welded with pins.

4. The series high-inductance molded inductor according to claim 1, characterized in that: The molded inductor also includes an insulating top cover, which is fixedly connected to the top of the soft magnetic metal block by adhesive; or the top of the soft magnetic metal block is coated with glue to make the common top of multiple soft magnetic metal blocks flat and without gaps.

5. The series high-inductance molded inductor according to claim 1, characterized in that: The metal conductor is copper foil, copper sheet, flat copper wire, round copper wire, enameled flat copper wire or enameled round copper wire.

6. The series high-inductance molded inductor according to claim 1, characterized in that: The soft magnetic metal block is in the shape of a cuboid, and the metal wire is centrally arranged in the soft magnetic metal block.

7. The series high-inductance molded inductor according to claim 1, characterized in that: The two ends of the metal wire are flattened to form pins; or the pins are connected by spot welding.

8. The series high-inductance molded inductor according to claim 1, characterized in that: The bent metal wires between the multiple soft magnetic metal blocks are fixed on the soft magnetic metal blocks by adhesive.

9. A method for forming a series high-inductance molded inductor as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: S1, placing a metal wire in a molding die, wherein the molding die has at least two cavities; S2, filling the soft magnetic metal powder into the cavity and pressing it into shape; S3, high temperature heat treatment; S4, bending the metal wire so that the multiple soft magnetic metal blocks are attached to each other and arranged in a row, and the sides of adjacent soft magnetic metal blocks are fixedly connected by adhesive; S5, forming the two ends of the metal wire into pins, or shaping the pins welded to the two ends of the metal wire.

10. The molding method according to claim 9, characterized in that: In step S3, the temperature of the high temperature heat treatment is 650°C to 850°C.

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