A manufacturing method of a chip inductor

Abstract

The present invention provides a manufacturing method of a chip inductor. The manufacturing method includes: (Ⅰ) winding a coil and bending the lead pins at both ends of the coil; (Ⅱ) providing a first mold, inserting the coil into the first mold, filling soft magnetic powder to form a magnet, and performing a primary pressing on the magnet so that the coil part is embedded in the magnet to obtain an initial inductor; (Ⅲ) demolding the initial inductor in step (Ⅱ), and respectively performing bevel cutting on the lead pins extending out of the magnet to form inductor leads to obtain an intermediate inductor; (Ⅳ) providing a second mold, and performing a secondary pressing on the intermediate inductor in step (Ⅲ) by using the second mold to obtain a chip inductor. The present invention solves the problem that large-pin electrodes cannot be bent, enabling large-pin plug-in inductors to achieve chip design.

Description

Technical Field

[0001] The present invention belongs to the technical field of inductive electrodes and relates to a manufacturing method of a chip inductor. Background Art

[0002] Chip inductors have unique advantages in fields such as consumer electronics, digital products, and automotive electronics. They mainly consist of three parts: a coil, a magnetic core, and electrodes. With the trend of electronic products developing towards smaller, lighter, and higher-performance directions, higher requirements are put forward for the reliability and integrated design of chip inductors.

[0003] In traditional integrated inductor processes, the production of electrodes mainly relies on bending. Usually, the two copper sheet electrodes of the inductor are bent to the bottom of the inductor to serve as inductor electrodes. However, this method is only applicable to the case where the copper sheet electrodes are relatively thin and easy to bend. When the electrode pins are relatively large, bending will cause product cracking or damage. Currently, inductors with large pins usually adopt a plug-in design, using two pins as inductor electrodes, but this method not only increases the space volume of the product but also is not conducive to surface mounting and miniaturization. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a manufacturing method of a chip inductor. After the lead-out feet of the coil are pressed once and then obliquely cut, the lead-out feet are deflected and converged inward, and then pressed a second time to form a chip structure, solving the problem that large-pin electrodes cannot be bent, and enabling large-pin plug-in inductors to achieve chip design.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] The present invention provides a manufacturing method of a chip inductor, and the manufacturing method includes:

[0007] (Ⅰ) Wind a coil and bend the lead-out feet at both ends of the coil;

[0008] (Ⅱ) Provide a first mold, insert the coil into the first mold, fill in soft magnetic powder to form a magnet, and perform a first pressing on the magnet so that part of the coil is embedded in the magnet to obtain an initial inductor;

[0009] (Ⅲ) Demold the initial inductor in step (Ⅱ), and respectively perform oblique cutting on the lead-out feet extending out of the magnet to form inductor pins to obtain an intermediate inductor;

[0010] (Ⅳ) Provide a second mold and perform a second pressing on the intermediate inductor in step (Ⅲ) using the second mold to obtain a chip inductor.

[0011] As a preferred technical solution of the present invention, in step (Ⅰ), the bending angle of the bending treatment is 60-120°, for example, it can be 60°, 65°, 70°, 80°, 90°, 100°, 110° or 120°, but is not limited to the listed values. Other unlisted values within this numerical range are equally applicable, and preferably 90°.

[0012] Preferably, the coil is wound with copper enameled wire and / or silver enameled wire.

[0013] It should be noted that the coil in the present invention refers to a ring-shaped wire winding. The enameled wire is a well-known wire winding for making coils in the art, which consists of a conductor and an insulating layer. After the bare wire is annealed and softened, it is painted and baked multiple times. The two ends of the wire winding are respectively provided with lead-out feet, which serve as the input end and output end of the coil. The lead-out feet are usually made of a material that is easy to bend, can be a flat structure, is relatively thin, and can be press-molded.

[0014] As a preferred technical solution of the present invention, in step (Ⅱ), the first mold includes a first upper mold, a first middle mold and a first lower mold. A through first cavity is opened in the first middle mold, and the first lower mold, the magnet and the first upper mold are sequentially placed in the first cavity for a first pressing.

[0015] Preferably, open slots are respectively provided on at least two side surfaces of the first lower mold. The open slots are used to accommodate the lead-out feet. At least two protrusions are provided on one side surface of the first lower mold close to the magnet, and the protrusions are respectively arranged at the openings of the open slots.

[0016] As a preferred technical solution of the present invention, in step (Ⅱ), the specific method for manufacturing the initial inductance includes:

[0017] Insert the lead-out feet of the coil into the open slots of the first lower mold respectively. Place the first lower mold with the coil in the first cavity of the first middle mold, and fill the first cavity with soft magnetic powder to form the magnet. Use the first upper mold to press down the magnet so that part of the coil is embedded in the magnet, and a patch groove is formed on the side of the magnet close to the protrusions of the first lower mold.

[0018] Preferably, in step (Ⅱ), the pressure of the first pressing is 10-14 T / cm 2 , for example, it can be 10.0 T / cm 2 , 11.0 T / cm 2 , 11.5 T / cm 2 , 12.0 T / cm 2 , 12.5 T / cm 2 , 13.0 T / cm 2, 13.5 T / cm 2 or 14.0 T / cm 2 , but not limited to the listed values, and other unlisted values within this range are equally applicable.

[0019] It should be noted that the first mold provided by the present invention is used for one-time pressing treatment to combine a coil and a magnet to form an initial inductor. The opening slots on the surface of the first lower mold match the size of the lead-out pins, facilitating the insertion of the lead-out pins. During the use of the first mold, first place the first lower mold with the inserted coil into the first cavity, leaving some space to fill with soft magnetic powder to form a magnet. Among them, during the downward pressing process, use the first upper mold to press down the soft magnetic powder. The magnet contacts the first lower mold, and all the annular wire windings of the coil are embedded in the magnet, with the lead-out pins at both ends exposed. The protrusions on the surface of the first lower mold form a patch groove on the surface of the magnet, completing one-time pressing. However, due to the fact that the lead-out pins of the coil partially protrude from the magnet, this initial inductor has a relatively large spatial volume, which is not conducive to the miniaturization of electronic components.

[0020] As a preferred technical solution of the present invention, the soft magnetic powder includes any one or a combination of at least two of Fe-Si alloy soft magnetic powder, Fe-Al alloy soft magnetic powder, Fe-Si-Al alloy soft magnetic powder, Fe-Ni alloy soft magnetic powder, Fe-Co alloy soft magnetic powder, Fe-based amorphous soft magnetic powder, Fe-based nanocrystalline soft magnetic powder, Co-based amorphous soft magnetic powder, Zn-Ni ferrite powder, or Zn-Mn ferrite powder.

[0021] It should be noted that the soft magnetic powder used in the present invention can be soft magnetic alloy soft powder, amorphous nanocrystalline soft magnetic powder, ferrite soft magnetic powder, etc.

[0022] As a preferred technical solution of the present invention, in step (Ⅲ), the angle formed by the bevel cutting is 30 - 60°, for example, it can be 30°, 35°, 40°, 45°, 50°, 55°, or 60°, but not limited to the listed values, and other unlisted values within this range are equally applicable.

[0023] It should be noted that in the present invention, the lead-out pins protruding from the magnet are bevel cut at their roots to obtain inductor pins with a bevel surface. The angle formed by this bevel surface and the horizontal plane is 30 - 60°, enabling the inductor pins to bend inward.

[0024] Preferably, the bevel cutting is performed by laser cutting, shearing, or punching.

[0025] As a preferred technical solution of the present invention, in step (IV), the second mold includes a second upper mold, a second middle mold and a second lower mold. A through second cavity is formed in the second middle mold, and the second lower mold, the intermediate inductor and the second lower mold are sequentially placed in the second cavity for secondary pressing.

[0026] As a preferred technical solution of the present invention, in step (IV), the secondary pressing includes:

[0027] The second lower mold and the intermediate inductor are sequentially placed in the second cavity of the second middle mold, the inductor pins are arranged close to the second lower mold, and the second upper mold is used to press down the magnet, so that the inductor pins are bent and embedded in the patch grooves of the magnet.

[0028] It should be noted that during the use of the second mold in the present invention, the inductor pins of the intermediate inductor are placed close to the second lower mold. The surface of the second lower mold is smooth. The second upper mold is used to press down the magnet, and the inductor pins are bent inward under pressure and flattened into the patch grooves of the magnet, being flat against the surface of the magnet to complete the secondary pressing.

[0029] It should also be noted that the intermediate inductor prepared by the present invention occupies less space than the initial inductor. However, since the inductor pins still have a structure protruding from the magnet, in order to further reduce its occupied space, secondary pressing treatment is adopted. During the secondary pressing process, the inductor pins with inclined surfaces can be bent inward and flattened. The patch grooves on the surface of the magnet provide a space for accommodating the flattened inductor pins, reducing the occupied space, which is beneficial to increasing the area of the inductor pins, thereby reducing the contact resistance and improving its reliability.

[0030] As a preferred technical solution of the present invention, in step (IV), the pressure of the secondary pressing is 12 - 20 T / cm 2 , for example, it can be 12.0 T / cm 2 , 12.5 T / cm 2 , 13.0 T / cm 2 , 13.5 T / cm 2 , 14.0 T / cm 2 , 15.0 T / cm 2 , 15.5 T / cm 2 , 16.0 T / cm 2 , 17.0 T / cm 2 , 18.0 T / cm 2 , 19.0 T / cm 2 or 20.0 T / cm 2 , but it is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0031] As a preferred technical solution of the present invention, the manufacturing method specifically includes the following steps:

[0032] (1) Wind a coil and bend the lead-out feet at both ends of the coil;

[0033] (2) Provide a first mold, which includes a first upper mold, a first middle mold and a first lower mold. A through first cavity is formed in the first middle mold. Open slots are respectively arranged on at least two side surfaces of the first lower mold. The open slots are used to accommodate the lead-out feet. The first lower mold is provided with at least two protrusions, and the protrusions are respectively arranged at the openings of the open slots;

[0034] (3) Place the coil in the first mold of step (2), insert the lead-out feet into the open slots of the first lower mold respectively, place the first lower mold with the coil in the first cavity of the first middle mold, and fill the first cavity with soft magnetic powder to form a magnet;

[0035] (4) Use the first upper mold to press down the magnet for a first pressing, so that the coil part is embedded in the magnet, and the lead-out feet respectively protrude from the magnet. A patch groove is formed on one side of the magnet close to the protrusion of the first lower mold to obtain an initial inductor. The pressure of the first pressing is 10-14 T / cm 2 ;

[0036] (5) Demold the initial inductor in step (4), and respectively perform bevel cutting on the lead-out feet protruding from the magnet to form inductor pins to obtain an intermediate inductor;

[0037] (6) Provide a second mold, which includes a second upper mold, a second middle mold and a second lower mold. A through second cavity is formed in the second middle mold;

[0038] (7) Place the second lower mold in the second cavity of the second middle mold, place the intermediate inductor in step (5) on the second lower mold, and use the second upper mold to press down the magnet for a second pressing. The inductor pins are bent and embedded in the patch groove of the magnet to obtain a surface mount inductor. The pressure of the second pressing is 12-20 T / cm 2 .

[0039] The numerical ranges described in the present invention not only include the point values exemplified above, but also include any point values between the above numerical ranges not exemplified. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the ranges.

[0040] Compared with the prior art, the beneficial effects of the present invention are:

[0041] A manufacturing method of a patch inductor provided by the present invention realizes the combination of a coil and a magnet through one-time pressing. Subsequently, the pins are obliquely cut, so that the inductor pins are deflected and can converge inward. Then, secondary pressing is performed to flatten the inductor pins and make them lie flat on the magnet, meeting the requirements of the patch inductor. It solves the problem that large-pin electrodes cannot be bent, does not affect the height of the product, saves space, is beneficial to increasing the contact area of the inductor electrodes, thereby reducing the contact resistance of the inductor electrodes and improving reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 FIG. is a schematic structural diagram of a coil provided by a specific embodiment of the present invention;

[0043] Figure 2 FIG. is a schematic structural diagram of a first mold provided by a specific embodiment of the present invention;

[0044] Figure 3 FIG. is a schematic structural diagram of a first lower mold provided by a specific embodiment of the present invention;

[0045] Figure 4 FIG. is a schematic structural diagram of a coil inserted into the first lower mold provided by a specific embodiment of the present invention;

[0046] Figure 5 FIG. is a schematic structural diagram of an initial inductor provided by a specific embodiment of the present invention;

[0047] Figure 6 FIG. is a schematic structural diagram of an intermediate inductor provided by a specific embodiment of the present invention;

[0048] Figure 7 FIG. is a schematic structural diagram of a second mold provided by a specific embodiment of the present invention;

[0049] Figure 8 FIG. is a sectional view of a second mold provided by a specific embodiment of the present invention;

[0050] Figure 9 FIG. is a schematic structural diagram of a patch inductor provided by a specific embodiment of the present invention.

[0051] Wherein, 1 - coil; 2 - first upper mold; 3 - first middle mold; 4 - first lower mold; 5 - opening slot; 6 - protrusion; 7 - magnet; 8 - patch groove; 9 - inductor pin; 10 - second upper mold; 11 - second middle mold; 12 - second lower mold. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0052] It should be understood that in the description of the present invention, the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0053] The technical solution of the present invention will be further described below with reference to the drawings and through specific embodiments.

[0054] In a specific embodiment, the present invention provides a method for manufacturing a patch inductor. The manufacturing method specifically includes the following steps:

[0055] Step 1: Wind coil 1 and bend the lead-out feet at both ends of the coil 1.

[0056] As Figure 1 shown, the bending angle of the bending treatment in the present invention is 60-120°.

[0057] In some embodiments, the coil 1 is wound with copper enameled wire and / or silver enameled wire. The coil 1 in the present invention refers to a ring-shaped wire winding. The enameled wire is a well-known wire winding for making the coil 1 and consists of a conductor and an insulating layer. Lead-out feet are respectively arranged at both ends of the wire winding as the input end and output end of the coil 1. The lead-out feet usually adopt materials that are easy to bend, can be of a flat structure, are relatively thin, and can be press-molded.

[0058] Step 2: Provide a first mold. As Figure 2 shown, the first mold includes a first upper mold 2, a first middle mold 3 and a first lower mold 4. A through first cavity is opened in the first middle mold 3. As Figure 3 shown, open slots 5 are respectively arranged on at least two side surfaces of the first lower mold 4. The open slots 5 are used to accommodate the lead-out feet. At least two protrusions 6 are arranged on the first lower mold 4, and the protrusions 6 are respectively arranged at the openings of the open slots 5.

[0059] Step 3: As Figure 4As shown, place the coil 1 in the first mold. Insert the lead pins into the open slots 5 of the first lower mold 4 respectively. Place the first lower mold 4 with the coil 1 in the first cavity of the first middle mold 3, and fill the first cavity with soft magnetic powder to form the magnet 7.

[0060] The open slots 5 on the surface of the first lower mold 4 used in the first mold provided by the present invention are matched with the sizes of the lead pins, which facilitates the insertion of the lead pins. During the use of the first mold, place the first lower mold 4 with the coil 1 inserted into the first cavity, and leave some space to fill the soft magnetic powder.

[0061] In some embodiments, the soft magnetic powder used in the present invention can be soft magnetic alloy soft powder, amorphous nanocrystalline soft magnetic powder, ferrite soft magnetic powder, etc. For example, it can be any one or at least two combinations of Fe-Si alloy soft magnetic powder, Fe-Al alloy soft magnetic powder, Fe-Si-Al alloy soft magnetic powder, Fe-Ni alloy soft magnetic powder, Fe-Co alloy soft magnetic powder, Fe-based amorphous soft magnetic powder, Fe-based nanocrystalline soft magnetic powder, Co-based amorphous soft magnetic powder, Zn-Ni ferrite powder or Zn-Mn ferrite powder.

[0062] Step Four: Use the first upper mold 2 to press down the magnet 7 for a first pressing, so that part of the coil 1 is embedded in the magnet 7. As Figure 5 shown, the lead pins extend out of the magnet 7 respectively, and a patch groove 8 is formed on one side of the magnet 7 close to the protrusion 6 of the first lower mold 4 to obtain the initial inductance. The pressure of the first pressing is 10 - 14 T / cm 2 .

[0063] The present invention uses the first mold for a first pressing treatment to combine the coil 1 and the magnet 7 to form the initial inductance. Use the first upper mold 2 to press down the soft magnetic powder. During the pressing process, the magnet 7 contacts the first lower mold 4. All the annular wire windings of the coil 1 are embedded in the magnet 7, and the lead pins at both ends are exposed. The protrusion 6 on the surface of the first lower mold 4 forms a patch groove 8 on the surface of the magnet 7 to complete the first pressing.

[0064] Step Five: Demold the initial inductance obtained in Step Four, and perform bevel cutting on the lead pins extending out of the magnet 7 respectively to form inductance pins 9 to obtain the intermediate inductance as Figure 6 shown.

[0065] In some embodiments, the bevel cutting treatment of the present invention uses laser cutting, shearing or punching, and the angle formed by the bevel cutting treatment is 30 - 60°.

[0066] The initial inductor obtained in Step 4 has a relatively large spatial volume because the lead-out feet of the coil 1 partially protrude from the magnet 7, which is not conducive to the miniaturization of electronic components. Therefore, in the present invention, the lead-out feet protruding from the magnet 7 are obliquely cut at their roots to obtain inductor pins 9 with inclined surfaces, and the angle formed by the inclined surface and the horizontal plane is 30 to 60°, so that the inductor pins 9 can be bent inward.

[0067] Step 6: Provide a second mold, as Figure 7 and Figure 8 shown, the second mold includes a second upper mold 10, a second middle mold 11 and a second lower mold 12, and a through second cavity is formed in the second middle mold 11.

[0068] Step 7: Place the second lower mold 12 in the second cavity of the second middle mold 11, and place the intermediate inductor in Step 5 on the second lower mold 12. The inductor pins 9 are arranged close to the second lower mold 12. Use the second upper mold 10 to press down the magnet 7 for secondary pressing. The inductor pins 9 are bent and embedded in the patch groove 8 of the magnet 7 to obtain a Figure 9 shown surface-mounted inductor. The pressure of the secondary pressing is 12 to 20 T / cm 2 .

[0069] The second mold in the present invention is used for the secondary pressing process. The inductor pins 9 of the intermediate inductor are placed close to the second lower mold 12. The surface of the second lower mold 12 is smooth. Use the second upper mold 10 to press down the magnet 7 of the intermediate inductor. The inductor pins 9 with inclined surfaces can be bent inward and flattened into the patch groove 8 of the magnet 7. The patch groove 8 provides a receiving space for the flattened inductor pins 9. The inductor pins 9 are flat against the surface of the magnet 7 to complete the secondary pressing. Further reduce its occupied space, which is beneficial to increasing the area of the inductor pins 9, thereby reducing the contact resistance and improving its reliability.

[0070] Example 1

[0071] This embodiment provides a method for manufacturing a surface-mounted inductor. The manufacturing method specifically includes the following steps:

[0072] (1) Wind the coil 1, and bend the lead-out feet at both ends of the coil 1. The bending angle is 90°;

[0073] (2) Provide a first mold. The first mold includes a first upper mold 2, a first middle mold 3 and a first lower mold 4. A through first cavity is formed in the first middle mold 3. Open slots 5 are respectively arranged on both side surfaces of the first lower mold 4 for accommodating the lead-out feet. Two protrusions 6 are arranged on the first lower mold 4, and the protrusions 6 are respectively arranged at the openings of the open slots 5;

[0074] (3) Place the coil 1 in the first mold of step (2), insert the lead-out feet into the open slots 5 of the first lower mold 4 respectively, place the first lower mold 4 with the coil 1 in the first cavity of the first middle mold 3, and fill the first cavity with soft magnetic powder to form a magnet 7. The soft magnetic powder uses Fe-Si-Al alloy soft magnetic powder;

[0075] (4) Use the first upper mold 2 to press down on the magnet 7 for the first pressing, so that part of the coil 1 is embedded in the magnet 7, the lead-out feet extend out of the magnet 7 respectively, and two patch grooves 8 are formed on one side of the magnet 7 close to the protrusion 6 of the first lower mold 4 to obtain an initial inductor. The pressure of the first pressing is 12 T / cm 2 ;

[0076] (5) Demold the initial inductor in step (4), and use laser cutting to obliquely cut the lead-out feet extending out of the magnet 7 respectively to form inductor pins 9 to obtain an intermediate inductor. The angle of the inductor pins 9 after oblique cutting is 60° (that is, the angle formed by the inclined plane of the inductor pins 9 and the horizontal plane), so that the inductor pins 9 can be bent inward;

[0077] (6) Provide a second mold. The second mold includes a second upper mold 10, a second middle mold 11 and a second lower mold 12. A through second cavity is opened in the second middle mold 11;

[0078] (7) Place the second lower mold 12 in the second cavity of the second middle mold 11, place the intermediate inductor in step (5) on the second lower mold 12, set the inductor pins 9 close to the second lower mold 12, use the second upper mold 10 to press down on the magnet 7 for the second pressing, and the inductor pins 9 are bent and respectively embedded in the patch grooves 8 of the magnet 7 to obtain a surface mount inductor. The pressure of the second pressing is 15 T / cm 2 。

[0079] Example 2

[0080] This embodiment provides a method for manufacturing a surface mount inductor. The manufacturing method specifically includes the following steps:

[0081] (1) Wind the coil 1 and bend the lead-out feet at both ends of the coil 1. The bending angle is 60°;

[0082] (2) Provide a first mold. The first mold includes a first upper mold 2, a first middle mold 3 and a first lower mold 4. A through first cavity is opened in the first middle mold 3. Open slots 5 are respectively arranged on both side surfaces of the first lower mold 4 for accommodating the lead-out feet. The first lower mold 4 is provided with two protrusions 6, and the protrusions 6 are respectively arranged at the openings of the open slots 5;

[0083] (3) Place the coil 1 in the first mold of step (2), insert the lead-out legs into the open slots 5 of the first lower mold 4 respectively, place the first lower mold 4 with the coil 1 in the first cavity of the first middle mold 3, and fill the first cavity with soft magnetic powder to form the magnet 7. The soft magnetic powder uses Zn-Ni ferrite powder;

[0084] (4) Use the first upper mold 2 to press down on the magnet 7 for the first pressing, so that part of the coil 1 is embedded in the magnet 7, and the lead-out legs extend out of the magnet 7 respectively. Two patch grooves 8 are formed on one side of the magnet 7 close to the protrusion 6 of the first lower mold 4 to obtain the initial inductor. The pressure of the first pressing is 10T / cm 2 ;

[0085] (5) Demold the initial inductor in step (4), and use laser cutting to perform bevel cutting on the lead-out legs extending out of the magnet 7 respectively to form inductor pins 9 to obtain the intermediate inductor. The angle of the beveled inductor pins 9 after bevel cutting is 45° (that is, the angle formed by the inclined plane of the inductor pins 9 and the horizontal plane), so that the inductor pins 9 can be bent inward;

[0086] (6) Provide a second mold. The second mold includes a second upper mold 10, a second middle mold 11 and a second lower mold 12. A through second cavity is opened in the second middle mold 11;

[0087] (7) Place the second lower mold 12 in the second cavity of the second middle mold 11, place the intermediate inductor in step (5) on the second lower mold 12, and arrange the inductor pins 9 close to the second lower mold 12. Use the second upper mold 10 to press down on the magnet 7 for the second pressing. The inductor pins 9 are bent and respectively embedded in the patch grooves 8 of the magnet 7 to obtain the surface-mounted inductor. The pressure of the second pressing is 12T / cm 2 。

[0088] Example 3

[0089] This embodiment provides a method for manufacturing a surface-mounted inductor. The manufacturing method specifically includes the following steps:

[0090] (1) Wind the coil 1 and bend the lead-out legs at both ends of the coil 1. The bending angle is 120°;

[0091] (2) Provide a first mold. The first mold includes a first upper mold 2, a first middle mold 3 and a first lower mold 4. A through first cavity is opened in the first middle mold 3. Open slots 5 are respectively arranged on both side surfaces of the first lower mold 4 for accommodating the lead-out legs. The first lower mold 4 is provided with two protrusions 6, and the protrusions 6 are respectively arranged at the openings of the open slots 5;

[0092] (3) Place the coil 1 in the first mold of step (2), insert the lead-out pins into the open slots 5 of the first lower mold 4 respectively, place the first lower mold 4 with the coil 1 in the first cavity of the first middle mold 3, and fill the first cavity with soft magnetic powder to form the magnet 7. The soft magnetic powder is Fe-Ni amorphous soft magnetic powder;

[0093] (4) Use the first upper mold 2 to press down on the magnet 7 for the first pressing, so that part of the coil 1 is embedded in the magnet 7, and the lead-out pins extend out of the magnet 7 respectively. Two patch grooves 8 are formed on one side of the magnet 7 close to the protrusion 6 of the first lower mold 4 to obtain the initial inductor. The pressure of the first pressing is 14 T / cm 2 ;

[0094] (5) Demold the initial inductor in step (4), and use laser cutting to perform bevel cutting on the lead-out pins extending out of the magnet 7 respectively to form inductor pins 9 to obtain the intermediate inductor. The angle of the inductor pins 9 after bevel cutting is 60° (that is, the angle formed by the inclined plane of the inductor pins 9 and the horizontal plane), so that the inductor pins 9 can be bent inward;

[0095] (6) Provide a second mold, which includes a second upper mold 10, a second middle mold 11 and a second lower mold 12. A through second cavity is opened in the second middle mold 11;

[0096] (7) Place the second lower mold 12 in the second cavity of the second middle mold 11, place the intermediate inductor in step (5) on the second lower mold 12, and arrange the inductor pins 9 close to the second lower mold 12. Use the second upper mold 10 to press down on the magnet 7 for the second pressing, and the inductor pins 9 are bent and embedded in the patch grooves 8 of the magnet 7 respectively to obtain the surface mount inductor. The pressure of the second pressing is 18 T / cm 2 。

[0097] The manufacturing method of the surface mount inductor provided by the present invention realizes the combination of the coil 1 and the magnet 7 through the first pressing, then performs oblique cutting on the pins, so that the inductor pins 9 can be deflected and converge inward, and then performs the second pressing to flatten the inductor pins 9 and make them flat against the magnet 7, meeting the requirements of the surface mount inductor, solving the problem that the large-pin electrodes cannot be bent, not affecting the height of the product, thus saving space, being beneficial to increasing the contact area of the inductor electrodes, thereby reducing the contact resistance of the inductor electrodes and improving the reliability.

[0098] The applicant declares that the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A manufacturing method of a patch inductor, characterized in that, the manufacturing method includes: (Ⅰ) winding a coil and bending the lead pins at both ends of the coil; (Ⅱ) providing a first mold, inserting the coil into the first mold, filling soft magnetic powder to form a magnet, and performing a first pressing on the magnet so that part of the coil is embedded in the magnet to obtain an initial inductor; (Ⅲ) demolding the initial inductor obtained in step (Ⅱ), and respectively performing bevel cutting on the lead pins protruding from the magnet to form inductor pins. The bevel cutting is to perform bevel cutting on the lead pins protruding from the magnet at their roots to obtain inductor pins with inclined surfaces, and obtain an intermediate inductor; (Ⅳ) providing a second mold, and performing a second pressing on the intermediate inductor in step (Ⅲ) using the second mold so that the inductor pins can be bent inward to obtain a patch inductor.

2. The manufacturing method according to claim 1, characterized in that, in step (Ⅰ), the bending angle of the bending treatment is 60-120°.

3. The manufacturing method according to claim 1, characterized in that, in step (Ⅰ), the bending angle of the bending treatment is 90°.

4. The manufacturing method according to claim 1, characterized in that, the coil is wound with copper enameled wire and / or silver enameled wire.

5. The manufacturing method according to claim 1, characterized in that, in step (Ⅱ), the first mold includes a first upper mold, a first middle mold and a first lower mold. A through first cavity is opened in the first middle mold, and the first lower mold, the magnet and the first upper mold are sequentially placed in the first cavity for the first pressing.

6. The manufacturing method according to claim 5, characterized in that, open slots are respectively arranged on at least two side surfaces of the first lower mold, and the open slots are used to accommodate the lead pins. At least two protrusions are arranged on one side surface of the first lower mold close to the magnet, and the protrusions are respectively arranged at the openings of the open slots.

7. The manufacturing method according to claim 6, characterized in that, in step (Ⅱ), the manufacturing method of the initial inductor specifically includes: inserting the lead pins of the coil into the open slots of the first lower mold respectively, placing the first lower mold with the coil in the first cavity of the first middle mold, filling soft magnetic powder into the first cavity to form the magnet, and using the first upper mold to press down the magnet so that part of the coil is embedded in the magnet, and a patch groove is formed on one side of the magnet close to the protrusion of the first lower mold.

8. The manufacturing method according to claim 1, characterized in that, In step (II), the pressure of the first pressing is 10~14T / cm 2 .

9. The manufacturing method according to claim 7, characterized in that, the soft magnetic powder includes any one or a combination of at least two of Fe-Si alloy soft magnetic powder, Fe-Al alloy soft magnetic powder, Fe-Si-Al alloy soft magnetic powder, Fe-Ni alloy soft magnetic powder, Fe-Co alloy soft magnetic powder, Fe-based amorphous soft magnetic powder, Fe-based nanocrystalline soft magnetic powder, Co-based amorphous soft magnetic powder, Zn-Ni ferrite powder or Zn-Mn ferrite powder.

10. The manufacturing method according to claim 1, characterized in that, in step (III), the angle formed by the chamfering process is 30 to 60°.

11. The manufacturing method according to claim 1, characterized in that, the chamfering process is performed by laser cutting, shearing or punching.

12. The manufacturing method according to claim 1, characterized in that, in step (IV), the second mold includes a second upper mold, a second middle mold and a second lower mold. A through second cavity is provided in the second middle mold. The second lower mold, the intermediate inductor and the second lower mold are sequentially placed in the second cavity for secondary pressing.

13. The manufacturing method according to claim 12, characterized in that, in step (IV), the secondary pressing includes: The second lower mold and the intermediate inductor are sequentially placed in the second cavity of the second middle mold. The inductor leads are arranged close to the second lower mold. The upper mold is used to press down the magnet, and the inductor leads are bent and embedded in the patch grooves of the magnet.

14. The manufacturing method according to claim 1, characterized in that, In step (IV), the pressure of the secondary pressing is 12 to 20 T / cm 2 .

15. The manufacturing method according to claim 1, characterized in that, the manufacturing method specifically includes the following steps: (1) Wind a coil and bend the lead-out feet at both ends of the coil; (2) Provide a first mold, which includes a first upper mold, a first middle mold and a first lower mold. A through first cavity is provided in the first middle mold. Open slots are provided on at least two side surfaces of the first lower mold. The open slots are used to accommodate the lead-out feet. The first lower mold is provided with at least two protrusions, and the protrusions are respectively arranged at the openings of the open slots; (3) Place the coil in the first mold of step (2). The lead-out feet are respectively inserted into the open slots of the first lower mold. Place the first lower mold with the coil in the first cavity of the first middle mold, and fill the first cavity with soft magnetic powder to form a magnet; (4) Use the first upper die to press down the magnet for the first pressing, so that the coil part is embedded in the magnet, the lead-out feet respectively protrude from the magnet, and a patch groove is formed on the side of the magnet close to the protrusion of the first lower die to obtain an initial inductor. The pressure for the first pressing is 10 - 14 T / cm 2 ; (5) Demold the initial inductor in step (4), and perform chamfering on the lead-out feet extending out of the magnet to form inductor leads to obtain an intermediate inductor; (6) Provide a second mold, which includes a second upper mold, a second middle mold and a second lower mold. A through second cavity is provided in the second middle mold; (7) Place the second lower die into the second cavity of the second middle die, and place the intermediate inductor in step (5) on the second lower die. The inductor pins are arranged close to the second lower die. Press the magnet with the second upper die for secondary pressing. The inductor pins are bent and embedded into the patch grooves of the magnet to obtain a surface-mounted inductor. The pressure for secondary pressing is 12 - 20 T / cm 2 .

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