Coil positioning lossless die casting method

Abstract

The invention discloses a coil positioning lossless die-casting method, which comprises the following steps of: bending a terminal of a coil to form a bent part; placing the substrate module into the bending part, and placing the core body module into the middle hole of the coil; filling powder outside the coil to obtain a combined body; and carrying out die casting on the assembly to obtain an inductor blank. According to the invention, the prefabricated sub-module is arranged in the area where the coil is easy to deform and the filled powder is easy to leak, and only the coil is filled with the powder, so that the prefabricated sub-module ensures that the coil is well supported in the die-casting process, the deformation quantity of the inductor blank is mainly borne by the external powder, and unexpected deformation or damage to the coil is not caused; and the production yield of the small-size inductor is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of inductance processing, and in particular to a coil positioning lossless die-casting method. Background Art

[0002] For small, precision inductors, the coils occupy a relatively large volume share of the inductor to achieve high inductance performance. However, when using powder-filled die-casting, this increased coil volume makes powder filling more difficult, increasing areas of missed powder filling, increasing the coil's compression deformation, and increasing the probability of irregular coil deformation. Unlike the uniform green body formed after powder compression, the shape of the coil and its relative position within the green body significantly influence inductance performance. Therefore, in the production of small inductors, prefabricated sub-modules and coils are now more commonly assembled using pre-die-casting, followed by a secondary die-casting process to avoid areas of missed powder filling.

[0003] However, although the prefabricated sub-module solves the problem of powder leakage, its relatively hard surface will cause lateral or longitudinal squeezing of the coil, which not only fails to effectively solve the problem of coil deformation, but may even further cause coil damage, and the yield rate has not been substantially improved. Summary of the Invention

[0004] The embodiment of the present invention discloses a coil positioning lossless die-casting method, comprising:

[0005] 101. Bend the terminal of the coil to form a bent portion;

[0006] 102. Place a base module in the bent portion and a core module in the center hole of the coil;

[0007] 103. Filling powder outside the coil to obtain an assembly;

[0008] 104. Perform die-casting on the assembly to obtain an inductor blank.

[0009] As an optional implementation, the method further includes:

[0010] The outer contour of the base module fits and fills the bent portion of the coil, and the outer contour of the core module fits and fills the center hole of the coil.

[0011] As an optional implementation, the method further includes:

[0012] One end of the core module touches the inner side of the base module, and the other end touches the powder.

[0013] As an optional embodiment, when the axial direction of the coil is perpendicular to the die-casting direction, the method further includes:

[0014] Both ends of the core module touch the powder.

[0015] As an optional embodiment, after inserting the base module into the bent portion and inserting the core module into the center hole of the coil, the method further includes:

[0016] A housing module is mounted on the outside of the coil to obtain a combined body.

[0017] As an optional implementation, the method further includes:

[0018] The material hardness of the base module and the core module is greater than the material hardness of the shell module.

[0019] As an optional implementation, the method further includes:

[0020] One end of the core module touches the inner side of the base module, and the other end touches the inner side of the shell module.

[0021] As an optional embodiment, when the axial direction of the coil is perpendicular to the die-casting direction, the method further includes:

[0022] Two ends of the core module respectively touch two sides of the inner wall of the shell module.

[0023] As an optional implementation, the method further includes:

[0024] The bottom of the outer contour of the base module is fitted to the bent terminal, and the top of the outer contour is fitted to the arc-shaped outer wall of the coil body.

[0025] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0026] Prefabricated sub-modules are placed in areas where the coil is prone to deformation and powder filling is prone to leakage. Powder is only filled on the outside of the coil. The prefabricated sub-module ensures that the coil is well supported during the die-casting process. The deformation of the inductor blank is mainly borne by the external powder, which will not cause unpredictable deformation or damage to the coil. The production yield of small-sized inductors is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1This is a schematic flow chart of a coil positioning lossless die-casting method disclosed in the present invention;

[0029] Figure 2 This is a schematic structural diagram of an assembly produced by a coil positioning lossless die-casting method disclosed in the present invention;

[0030] Figure 3 This is a partial structural decomposition diagram of an assembly produced by a coil positioning lossless die-casting method disclosed in the present invention;

[0031] Figure 4 It is a schematic flow chart of another coil positioning lossless die-casting method disclosed in the present invention;

[0032] Figure 5 It is a structural schematic diagram of an assembly produced by another coil positioning lossless die-casting method disclosed in the present invention.

[0033] The main structural symbols are described in the following table:

[0034] Coil 1 Bending section 11 Mesopore 12 Base module 2 Core module 3 Housing module 4 powder 5 DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0036] Example 1

[0037] See also Figures 1 to 3 , the coil positioning lossless die casting method may include the following contents.

[0038] 101. Bend the terminals of the coil to form a bent portion.

[0039] Here, the pre-bending of the terminal, on the one hand, forms a bent portion 11 for accommodating and assembling the base module 2 , and on the other hand, avoids damage to the inductor body caused by large-angle bending, which is conducive to further improving the yield rate.

[0040] 102. Place the base module in the bent portion and place the core module in the center hole of the coil.

[0041] Here, the base module 2 and the core module 3 serve as filling parts, and obtain an initial contour with high density and hardness through pre-die casting, providing good support for the coil 1 during the subsequent secondary die casting, ensuring that the coil 1 will not deform beyond the expected range. When the coil 1 is accurately positioned and the deformation is small, the yield rate of the inductor product is improved accordingly.

[0042] As an optional embodiment, the outer contour of the base module 2 fits the bent portion 11 of the filling coil 1 , and the outer contour of the core module 3 fits the center hole 12 of the filling coil 1 .

[0043] Specifically, the base module 2 fits the bent portion 11 of the coil 1, and the core module 3 fits the center hole 12 of the coil 1, so that the bent portion 11 and the powder-missing areas that may exist inside the coil 1 can be tightly filled by the base module 2 or the core module 3 during the subsequent secondary die-casting process, ensuring that the material of the prepared inductor blank is uniform and the inductor performance is excellent.

[0044] It can be understood that the coil 1 style involved in this embodiment is a single-winding multi-turn coil 1. For different coil 1 styles such as multi-winding coil 1 or half-turn coil 1, the style of the base module 2 or the core module 3 should be adjusted along with the coil 1 style to ensure that effective support is provided for the area of ​​the coil 1 that is prone to excessive deformation, so that the deformation range of the coil 1 in the subsequent die-casting process can be controlled without affecting the inductance performance.

[0045] 103. Fill the outside of the coil with powder to obtain an assembly.

[0046] Here, the powder material 5 is filled outside the coil 1 to cover the coil 1 .

[0047] As an optional embodiment, one end of the core module 3 touches the inner side of the base module 2 , and the other end touches the powder 5 .

[0048] Here, one end of the core module 3 contacts the base module 2, and the other end contacts the powder 5 covering the outside of the coil 1. Therefore, after molding, the inductor shell formed by the powder 5 is integrated with the core module 3 and the base module 2 to form a complete inductor blank.

[0049] It is understandable that the die-casting direction of the inductor configuration exemplified in this embodiment is parallel to the axial direction of the coil 1 , but in actual production, there are also inductor configurations in which the axis of the coil 1 is perpendicular to the die-casting direction.

[0050] As an optional embodiment, when the axial direction of the coil 1 is perpendicular to the die-casting direction, both ends of the core module 3 touch the powder 5 .

[0051] In this case, the core module 3 is placed horizontally in the inductor body, and is eventually integrated with the inductor shell formed by the powder 5 , without making contact with the base module 2 .

[0052] 104. The assembly is die-casted to obtain an inductor blank.

[0053] Here, the assembly is placed in a mold, which includes a coil 1, which is internally supported by a base module 2 and a core module 3, and the outside of the coil 1 is filled with powder 5. The assembly is subjected to high-pressure die-casting through the mold, and can optionally be sintered at high temperature at the same time to compress the powder 5 and integrate it with the base module 2 and the core module 3.

[0054] During this process, the powder 5 provides the main deformation margin. At the same time, the coil 1 is supported by the base module 2 and the core module 3, and the deformation amount is maintained within a controllable range. It will not be deformed or damaged due to excessive deformation or rigid friction. Accordingly, the production yield of small-size inductors is greatly improved.

[0055] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0056] Prefabricated sub-modules are placed in areas where the coil is prone to deformation and powder filling is prone to leakage. Powder is only filled on the outside of the coil. The prefabricated sub-module ensures that the coil is well supported during the die-casting process. The deformation of the inductor blank is mainly borne by the external powder, which will not cause unpredictable deformation or damage to the coil. The production yield of small-sized inductors is greatly improved.

[0057] Example 2

[0058] See also Figures 4-5 , the coil positioning lossless die casting method may include the following contents.

[0059] 201. Bend the terminal of the coil to form a bent portion.

[0060] 202. Place the base module in the bent portion and place the core module in the center hole of the coil.

[0061] 203. A housing module is mounted on the outside of the coil to obtain an assembly.

[0062] Here, in addition to filling the powder 5 outside the coil 1, a prefabricated shell module 4 can also be assembled outside the coil 1. Compared with directly filling the powder 5, the prefabricated shell module 4 can effectively improve the accuracy of feeding, reduce the complexity of the production and assembly process, further improve the consistency of the inductor product, and help improve the yield rate.

[0063] As an optional embodiment, the material hardness of the base module 2 and the core module 3 is greater than the material hardness of the shell module 4 .

[0064] Specifically, similar to the powder 5 filled outside the coil 1, the deformation of the inductor blank during the die-casting process is mainly borne by the shell module 4. Therefore, when pre-pressing the base module 2, the core module 3 and the shell module 4, the material hardness of the shell module 4 should be less than that of the base module 2 and the core module 3, thereby ensuring that the coil 1 will not be subject to additional rigid friction and extrusion of the shell module 4 under the support of the base module 2 and the core module 3, thereby avoiding excessive deformation or even damage of the coil 1.

[0065] As an optional embodiment, one end of the core module 3 touches the inner side of the base module 2 , and the other end touches the inner side of the shell module 4 .

[0066] As an optional embodiment, when the axial direction of the coil 1 is perpendicular to the die-casting direction, both ends of the core module 3 touch both sides of the inner wall of the shell module 4 respectively.

[0067] Here, the housing module 4 is finally integrated with the base module 2 and the core module 3 to obtain an inductor body with uniform material density.

[0068] As an optional implementation, the bottom of the outer contour of the base module 2 fits the bent terminal, and the top of the outer contour fits the curved outer wall of the coil 1 body.

[0069] 204. Die-cast the assembly to obtain an inductor blank.

[0070] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0071] As the coil is prone to deformation, with the support of prefabricated sub-modules of different density and hardness, the deformation of the inductor body is mainly borne by the external powder or shell module. The coil deformation is controllable and no damage occurs, which greatly improves the production yield of small-sized inductors.

Claims

1. A coil positioning lossless die casting method, characterized in that: The method comprises:

101. Bend the terminal of the coil to form a bent portion; 102. Place a base module in the bent portion and a core module in the center hole of the coil; 103. Filling powder outside the coil to obtain an assembly; 104. Perform die-casting on the assembly to obtain an inductor blank.

2. A coil positioning lossless die casting method according to claim 1, characterized in that: The method further comprises: The outer contour of the base module fits and fills the bent portion of the coil, and the outer contour of the core module fits and fills the center hole of the coil.

3. The coil positioning lossless die casting method according to claim 2, characterized in that: The method further comprises: One end of the core module touches the inner side of the base module, and the other end touches the powder.

4. A coil positioning lossless die casting method according to claim 3, characterized in that: When the axial direction of the coil is perpendicular to the die-casting direction, the method further comprises: Both ends of the core module touch the powder.

5. The coil positioning lossless die casting method according to claim 1, characterized in that: After inserting the base module into the bent portion and inserting the core module into the center hole of the coil, the method further includes: A housing module is mounted on the outside of the coil to obtain a combined body.

6. The coil positioning lossless die casting method according to claim 5, characterized in that: The method further comprises: The material hardness of the base module and the core module is greater than the material hardness of the shell module.

7. The coil positioning lossless die casting method according to claim 5, characterized in that: The method further comprises: One end of the core module touches the inner side of the base module, and the other end touches the inner side of the shell module.

8. The coil positioning lossless die casting method according to claim 5, characterized in that: When the axial direction of the coil is perpendicular to the die-casting direction, the method further comprises: Two ends of the core module respectively touch two sides of the inner wall of the shell module.

9. The coil positioning lossless die casting method according to claim 8, characterized in that: The method further comprises: The bottom of the outer contour of the base module is fitted to the bent terminal, and the top of the outer contour is fitted to the arc-shaped outer wall of the coil body.

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