Duplex winding inductor die-casting method and die-casting die thereof

Abstract

The invention discloses a double-winding inductor die-casting method and a die-casting die thereof.The method comprises the steps that a first winding and a second winding are assembled in a combined mode, and a double-winding coil is obtained; the first pressing rod is arranged in the cavity and is stopped at a first stopping position; filling the cavity for the first time; a duplex winding coil is assembled in the positioning groove; carrying out secondary filling on the cavity; the second pressing rod is arranged in the cavity and is stopped at a second stopping position; the first pressing rod and the second pressing rod synchronously move in opposite directions and are parked at a target parking position; the first pressing rod and the second pressing rod are separated from the cavity; and separating the surrounding mold, and carrying out terminal bending and surface treatment on the inductor blank. According to the method, the duplex winding coil and the powder are subjected to hot die casting, rigid friction extrusion of the hard sub-module on the duplex winding coil is avoided, it is ensured that the duplex winding coil does not deform or displace, under the conditions that the iron content of the powder is increased and the machining difficulty is increased, the duplex winding inductor which is stable in coil positioning and high in performance consistency is manufactured, the yield is greatly increased, and the production cost is reduced. The production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of inductor processing, and in particular to a double-winding inductor die-casting method and a die-casting mold thereof. Background Art

[0002] The traditional production process of inductor products requires the use of powder to pre-press multiple sub-modules, assemble a coil on one of the sub-modules, and then assemble other sub-modules to form a combination, and then hot-die-cast the combination to obtain the inductor blank. This process is fast and reliable when producing basic single-winding inductors, and its consistency can meet the performance requirements of civilian-grade electronic circuits.

[0003] With the development of AI technology, various chip boards have put forward higher performance requirements for inductor products. In actual applications, inductor products produced by the above traditional processes have gradually exposed poor performance consistency and low compliance rate. The reason is that the pre-die-cast submodule and the coil produce rigid friction and extrusion between each other during the subsequent hot die-casting process, causing irregular deformation and displacement of the coil, which ultimately affects the performance consistency between the finished inductors. In addition, higher performance requirements also cause the iron content in the powder to continue to increase, further increasing the difficulty of processing.

[0004] The above problems are particularly prominent in double-winding inductors. The stacked double-winding coils are more likely to suffer surface damage during the hot die-casting process, the insulation layer is damaged, and the relative position of the double-winding coils is also affected. In addition to poor performance consistency, the scrap rate is also difficult to reduce. Summary of the invention

[0005] A first aspect of an embodiment of the present invention discloses a double-winding inductor die-casting method, comprising:

[0006] 101. Combine and assemble the first winding and the second winding to obtain a double-winding coil;

[0007] 102. Control the first pressing rod to be placed into one end of the cavity of the surrounding mold and to stop at a first stop position of the cavity;

[0008] 103. Filling the cavity for the first time;

[0009] 104. Assemble the double-winding coil based on the positioning groove on the inner wall of the cavity;

[0010] 105. Fill the cavity with a secondary filler;

[0011] 106. Control the second pressing rod to be placed into the other end of the cavity and to stop at a second stop position of the cavity;

[0012] 107. Control the first pressing rod and the second pressing rod to move synchronously toward each other and stop at a target stop position of the cavity;

[0013] 108. Control the first pressing rod and the second pressing rod to separate from the mold cavity;

[0014] 109. Control the surrounding mold to separate, and demold the inductor blank located inside the cavity;

[0015] 110. Perform terminal bending and surface treatment on the inductor blank to obtain a dual-winding inductor.

[0016] As an optional implementation, the second winding is coated on the outer surface of the first winding.

[0017] As an optional implementation, the first winding and the second winding are bonded together by adhesive.

[0018] As an optional implementation, the adhesive is coated on the surface of the first winding and the second winding, and is cured to form a protective layer.

[0019] As an optional implementation, a surface of either the first winding or the second winding is provided with an enamel layer.

[0020] As an optional implementation, a heating device is installed inside the surrounding mold;

[0021] The upper limit of the heating temperature of the heating device is lower than the melting threshold of the enamel layer.

[0022] As an optional implementation, both ends of the first winding are flattened.

[0023] As an optional implementation, outer contours of both ends of the flattened first winding are adapted to the inner contour of the positioning groove.

[0024] A second aspect of an embodiment of the present invention discloses a die-casting mold, comprising:

[0025] A surrounding mold (1) having a mold cavity (111) extending therethrough, wherein a first pressure rod (2) is disposed at one axial end of the mold cavity (111) and a second pressure rod (3) is disposed at the other axial end;

[0026] The first pressure rod (2) and the second pressure rod (3) both run along the axial direction of the cavity (111);

[0027] The enclosure mold (1) is composed of a cavity component (11) and an enclosure component (12) assembled together;

[0028] The cavity (111) is provided on a side of the cavity component (11), and the enclosure component (12) is fitted on one side of the cavity (111) of the cavity component (11);

[0029] A positioning groove (121) is provided on the inner side of the enclosure component (12);

[0030] A side wall (112) is provided on one side of the cavity component (11) that is in contact with the enclosure component (12), and a side groove (122) is provided on one side of the enclosure component (12) that is in contact with the cavity component (11) for accommodating the protruding side wall (112);

[0031] The cavity component (11) and the enclosure component (12) are both equipped with heating devices (4).

[0032] Preferably, the positioning groove (121) is used for positioning and assembling the first winding with both ends flattened;

[0033] The first pressing rod (2) and the second pressing rod (3) are used to synchronously run towards each other from both ends of the cavity (111) to perform die-casting on the powder contained in the cavity (111) and the double-winding coil covered by the powder, and the heating device (4) simultaneously performs heating treatment.

[0034] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0035] The double-winding coil and powder are directly hot-die-casted to avoid rigid friction and extrusion of the double-winding coil by the hard sub-module, ensuring that the double-winding coil does not deform or displace. When the iron content of the powder increases and the processing difficulty increases, a double-winding inductor with stable positioning and high performance consistency is obtained, which greatly improves the yield rate and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. 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 creative work.

[0037] Figure 1 It is a schematic diagram of a process of a double-winding inductor die-casting method disclosed in the present invention;

[0038] Figure 2 It is a three-dimensional structural schematic diagram of a die-casting mold disclosed in the present invention;

[0039] Figure 3 It is a structural schematic diagram of the top surface of a die-casting mold disclosed in the present invention;

[0040] Figure 4 It is a partial structural schematic diagram of a die-casting mold disclosed in the present invention;

[0041] Figure 5 It is a partial structural schematic diagram of a double-winding coil assembled in an enclosure component in a die-casting mold disclosed by the present invention;

[0042] Figure 6 It is a structural schematic diagram of an inductor blank disclosed in the present invention;

[0043] Figure 7 It is a schematic diagram of the cross-sectional structure of an inductor blank disclosed in the present invention;

[0044] Figure 8 It is a structural schematic diagram of a double-winding inductor obtained by bending terminals and performing surface treatment on an inductor blank disclosed in the present invention.

[0045] The main structural symbols are described in the following table:

[0046] Surrounding mold 1 Cavity components 11 Cavity 111 Sidewall 112 Enclosure components 12 Positioning slot 121 Side groove 122 First pressure rod 2 Second pressure rod 3 Heating device 4 Double winding coil S First winding A Inductor body P Second winding B DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Embodiment 1

[0049] See also Figure 1 , the dual-winding inductor die-casting method may include the following contents.

[0050] 101. The first winding and the second winding are assembled together to obtain a double-winding coil.

[0051] In this embodiment, the relative position of the first winding and the second winding of the double-winding coil has an impact on the inductance performance, so the two need to be combined and assembled before die-casting.

[0052] As an optional implementation, the second winding is wrapped around the outer surface of the first winding.

[0053] As an optional implementation, the first winding and the second winding are bonded by adhesive.

[0054] Here, the first winding and the second winding are bonded by using an adhesive, so that the two are well positioned without using an additional positioning jig or clamp to ensure that the relative position remains unchanged.

[0055] As an optional implementation, the adhesive is coated on the surface of the first winding and the second winding, and is cured to form a protective layer.

[0056] Here, the cured adhesive also protects and isolates the surfaces of the first winding and the second winding, preventing the powder from directly contacting the windings, further reducing the external influence on the double-winding coil during the hot die casting process, and ensuring that the relative position between the first winding and the second winding remains unchanged.

[0057] In addition, the glue gradually melts during the hot die-casting process, and no specific glue layer is produced between the powder and the coil, ensuring stable and consistent inductance performance.

[0058] As an optional implementation, either the first winding or the second winding has an enamel layer on its surface.

[0059] Here, at least one of the first winding and the second winding has an enamel layer, thereby ensuring insulation between the two.

[0060] In addition, the two are bonded together by adhesive, which further protects the enamel layer and prevents the enamel layer from being damaged during the die-casting process.

[0061] 102. Control the first pressing rod to be placed into one end of the cavity of the surrounding mold and stop at a first stop position of the cavity.

[0062] In this embodiment, the first pressing rod is first placed into the bottom of the cavity to seal the bottom of the cavity and form a closed filling space with the cavity and the side wall, so as to provide a first filling space for step 103 .

[0063] Here, the first parking position is set based on the specification of the inductor, which is used to ensure that after the first filling, the surface of the powder does not shield the positioning groove, which is convenient for the subsequent assembly of the coil.

[0064] 103. Fill the cavity for the first time.

[0065] In this embodiment, powder material for die-casting the core of one side of the inductor is filled into the cavity, so as to be used for assembling the coil inside the inductor in step 104 .

[0066] 104. Assemble the double-winding coil based on the positioning groove on the inner wall of the cavity.

[0067] In this embodiment, a positioning groove is provided on the inner wall of the cavity, and the positioning groove is used to limit the position of the coil to ensure that the coil is fixed in position and does not shift during the subsequent die-casting process. The coil can be positioned accordingly, and the powder can be die-casted synchronously from both sides to the middle to avoid the situation where the coil and the pre-pressed sub-module generate rigid extrusion friction and displacement deformation during the die-casting process, thereby obtaining an inductor blank with accurate coil positioning, high consistency and high yield rate.

[0068] As an optional implementation, two ends of the first winding are flattened.

[0069] The outer contours of the two ends of the flattened first winding are adapted to the inner contour of the positioning groove.

[0070] Here, both ends of the first winding are flattened without pre-bending, while both ends of the second winding are pre-bent, so that both ends of the first winding extend outward and can be inserted into the positioning groove for positioning and assembly. At the same time, after pre-bending, both ends of the second winding can ensure that they do not affect the insertion of the two ends of the first winding.

[0071] 105. Fill the cavity with secondary filling.

[0072] In this embodiment, powder material for die-casting the iron core on the other side of the inductor is filled into the cavity so that the double-winding coil assembled and limited in the cavity is surrounded by the powder material.

[0073] As an optional implementation, the surrounding mold may also be equipped with a vibration device, which is used to vibrate the powder in the cavity after filling, to ensure that the powder specifications on both sides of the coil are consistent as much as possible, and to improve the yield and consistency of the finished product.

[0074] 106. Control the second pressing rod to be placed into the other end of the cavity and to stop at a second stop position of the cavity.

[0075] In this embodiment, for the cavity in which the coil has been assembled and filled, the second pressing rod is inserted from the unsealed end of the cavity and stops at the second stopping position.

[0076] Here, the first stop position is symmetrical with the first stop position based on the positioning groove, so that the first pressing rod and the second pressing rod are in a synchronous state, waiting for synchronous die-casting of the powder and the coil in the powder.

[0077] 107. Control the first pressing rod and the second pressing rod to move synchronously toward each other and stop at a target stop position of the cavity.

[0078] Here, the target stopping position is the final specification of the die casting, that is, the outer shape specification of the inductor.

[0079] During the synchronous die-casting process, the powder materials are uniform in material and their shapes change in a consistent manner. There is no friction or crushing between the pre-pressed sub-modules and the coils, and the coil body will not be damaged. This effectively ensures the consistent performance of the finished inductor and greatly improves the yield rate.

[0080] In this embodiment, during the die-casting process, the surrounding mold heats the powder in a high-pressure state synchronously, and the powder is densely combined and fused by high temperature and high pressure to form a blank of a dual-winding inductor.

[0081] As an optional implementation, a heating device is installed inside the surrounding mold;

[0082] Here, depending on the composition ratio of the powder and the process requirements, the die casting process can choose whether to perform hot die casting on the powder.

[0083] That is, when only die casting is performed, the heating device is not operated. However, when hot die casting is performed, the heating device is operated at the same time as die casting, and the powder is subjected to high temperature and high pressure treatment to obtain a compact integrated inductor blank.

[0084] The upper limit of the heating temperature of the heating device is lower than the melting threshold of the enamel layer.

[0085] For example, conventional enameled coatings will melt and denature at temperatures above 180°C, losing their insulating protective properties. Therefore, for double-winding coils that have been enameled, the upper limit of the heating temperature of the heating device should be lower than the melting threshold of the enameled layer to avoid damaging the insulation effect of the double-winding coil and reduce the scrap rate.

[0086] 108. Control the first pressure rod and the second pressure rod to separate from the cavity.

[0087] Here, the first pressing rod and the second pressing rod are separated from the mold cavity first.

[0088] 109. Control the separation of the surrounding mold to demould the inductor blank located inside the cavity.

[0089] Here, after the first pressing rod and the second pressing rod are separated from the cavity, the two ends of the coil of the inductor blank are still placed in the positioning groove, so the surrounding mold is separated here so that the inductor blank can be separated from the positioning groove and fall off as a whole.

[0090] 110. Perform terminal bending and surface treatment on the inductor blank to obtain a double-winding inductor.

[0091] In this embodiment, the inductor blank has been formed into a standard specification, and can be subjected to surface painting, paint stripping and other operations, and the vertical terminals can be bent to form a standard inductor product.

[0092] If the terminal of the second winding is bent toward the outside, the terminal of the first winding is bent toward the inside, so as to ensure that the first winding and the second winding are insulated from each other.

[0093] In summary, the double-winding coil and powder are directly hot-die-casted to avoid rigid friction and extrusion of the double-winding coil by the hard sub-module, ensuring that the double-winding coil does not deform or displace. When the iron content of the powder increases and the processing difficulty increases, a double-winding inductor with stable positioning and high performance consistency is obtained, which greatly improves the yield rate and improves production efficiency at the same time.

[0094] Embodiment 2

[0095] See also Figures 2 to 8 , the die casting mold may include the following contents.

[0096] A surrounding mold 1 is provided through the cavity 111, a first pressing rod 2 is provided at one axial end of the cavity 111, and a second pressing rod 3 is provided at the other axial end;

[0097] The first pressing rod 2 and the second pressing rod 3 both run along the axial direction of the cavity 111;

[0098] The surrounding mold 1 is composed of a cavity component 11 and a surrounding component 12;

[0099] A cavity 111 is formed on the side of the cavity component 11 , and one side of the cavity 111 of the cavity component 11 is fitted with the enclosure component 12 ;

[0100] A positioning groove 121 is formed inside the enclosure component 12;

[0101] A side wall 112 is provided on one side of the cavity assembly 11 that is in contact with the enclosure assembly 12, and a side groove 122 is provided on one side of the enclosure assembly 12 that is in contact with the cavity assembly 11 to accommodate the protruding side wall 112;

[0102] The heating device 4 is installed inside the cavity component 11 and the enclosure component 12 .

[0103] In this embodiment, the cavity assembly and the enclosure assembly constitute a surrounding mold of the through-type cavity, and the first pressure rod and the second pressure rod are inserted from both ends of the cavity, and cooperate with the heating device to perform hot die casting on the powder in the cavity and the coil covered therein.

[0104] During the die-casting process, both ends of the coil are placed in positioning grooves to achieve positioning and limiting, thereby ensuring that the coil does not move under high pressure and high temperature conditions. The powder material gradually solidifies around the periphery of the coil to obtain an inductor with uniform core material density, complete coil and high consistency.

[0105] Compared with the traditional process of prefabricating sub-modules and then assembling coils, the method of hot die-casting powder and coils effectively avoids direct extrusion and scratching between the coils and the hard sub-modules. The impact of the powder curing process on the coils is significantly reduced, and the coil offset, deformation, breakage, etc. are greatly reduced, thereby improving the yield rate.

[0106] At the same time, the process flow of prefabricated submodules has been streamlined, which also means that various molds and die-casting equipment for preparing submodules have been streamlined. Taking the simplest case of using two submodules to press together a coil as an example, the traditional process requires the prefabrication of two submodules, so two molds corresponding to the two submodules are required. In the case of mass production, the number of molds is relatively large, the equipment cost is high, and the labor cost and time occupied by assembling the mold cannot be ignored. This solution directly performs die-casting on the powder, eliminating the equipment cost, labor cost and time cost required by the previous process, which is conducive to reducing production costs and improving production efficiency.

[0107] As an optional implementation, the positioning groove 121 is used for positioning and assembling the first winding with flattened ends;

[0108] The first pressing rod 2 and the second pressing rod 3 are used to synchronously run towards each other from both ends of the cavity 111 to perform die-casting on the powder contained in the cavity 111 and the double-winding coil covered by the powder, and are heated by the heating device 4 simultaneously.

[0109] Here, the positioning groove is used to position the limit coil, so that during the hot die casting process, the position of the coil remains unchanged, and the first pressure rod and the second pressure rod die-cast the powder around the coil from both sides to obtain an inductor product with high consistency and high yield.

Claims

1. A double-winding inductor die-casting method, characterized in that: The method comprises:

101. Combine and assemble the first winding and the second winding to obtain a double-winding coil; 102. Control the first pressing rod to be placed into one end of the cavity of the surrounding mold and to stop at a first stop position of the cavity; 103. Filling the cavity for the first time; 104. Assemble the double-winding coil based on the positioning groove on the inner wall of the cavity; 105. Fill the cavity with a secondary filler; 106. Control the second pressing rod to be placed into the other end of the cavity and to stop at a second stop position of the cavity; 107. Control the first pressing rod and the second pressing rod to move synchronously toward each other and stop at a target stop position of the cavity; 108. Control the first pressing rod and the second pressing rod to separate from the mold cavity; 109. Control the surrounding mold to separate, and demold the inductor blank located inside the cavity; 110. Perform terminal bending and surface treatment on the inductor blank to obtain a dual-winding inductor.

2. A double-winding inductor die-casting method according to claim 1, characterized in that: include: The second winding is covered on the outer surface of the first winding.

3. A double-winding inductor die-casting method according to claim 2, characterized in that: include: The first winding and the second winding are bonded together by adhesive.

4. A double-winding inductor die-casting method according to claim 3, characterized in that: include: The adhesive is coated on the surfaces of the first winding and the second winding, and is cured to form a protective layer.

5. A double-winding inductor die-casting method according to claim 2, characterized in that: include: A surface of either the first winding or the second winding is provided with an enamel layer.

6. A double-winding inductor die-casting method according to claim 6, characterized in that: include: A heating device is installed inside the surrounding mold; The upper limit of the heating temperature of the heating device is lower than the melting threshold of the enamel layer.

7. A double-winding inductor die-casting method according to claim 2, characterized in that: include: Both ends of the first winding are flattened.

8. A double-winding inductor die-casting method according to claim 7, characterized in that: include: The outer contours of the two ends of the flattened first winding are adapted to the inner contour of the positioning groove.

9. A die-casting mold used in the double-winding inductor die-casting method according to any one of claims 1 to 8, characterized in that: A surrounding mold (1) having a mold cavity (111) extending therethrough, wherein a first pressure rod (2) is disposed at one axial end of the mold cavity (111) and a second pressure rod (3) is disposed at the other axial end; The first pressure rod (2) and the second pressure rod (3) both run along the axial direction of the cavity (111); The enclosure mold (1) is composed of a cavity component (11) and an enclosure component (12) assembled together; The cavity (111) is provided on a side of the cavity component (11), and the enclosure component (12) is fitted on one side of the cavity (111) of the cavity component (11); A positioning groove (121) is provided on the inner side of the enclosure component (12); A side wall (112) is provided on one side of the cavity component (11) that is in contact with the enclosure component (12), and a side groove (122) is provided on one side of the enclosure component (12) that is in contact with the cavity component (11) for accommodating the protruding side wall (112); The cavity component (11) and the enclosure component (12) are both equipped with heating devices (4).

10. A die-casting mold according to claim 9, characterized in that: include: The positioning groove (121) is used for positioning and assembling the first winding with two ends flattened; The first pressing rod (2) and the second pressing rod (3) are used to synchronously run towards each other from both ends of the cavity (111) to perform die-casting on the powder contained in the cavity (111) and the double-winding coil covered by the powder, and the heating device (4) simultaneously performs heating treatment.

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