A method of producing a base integrated with a coil and a voice coil motor base

Abstract

The application provides a coil-integrated base production method and a voice coil motor base, and relates to the technical field of voice coil motor base production. The method comprises a base primary forming, injection molding, coil attaching, base secondary forming and injection molding. First, an initial embryo semi-finished product is formed by sequentially performing the base primary forming, injection molding, coil attaching, then the initial embryo semi-finished product is bent according to a preset shape and placed into a secondary injection mold, plastic material is injected into the secondary injection mold for secondary encapsulation forming, and a complete plastic-encapsulated finished product initial embryo is formed. Through the integrated design of the stage stamping, injection molding and attaching processes, a closed loop is formed from the base plate manufacturing to the final encapsulation, an efficient and cooperative production process is formed, the bottleneck of manual operation is effectively eliminated, the production efficiency and positioning accuracy are improved, and the batch production demand is met.

Description

Technical Field

[0001] This invention relates to the field of voice coil motor base manufacturing technology, and more specifically, to a method for manufacturing a base with an integrated coil and a voice coil motor base. Background Technology

[0002] The bonding process between the coil and the integrated circuit in the manufacturing of voice coil motor bases faces significant challenges. Existing processes generally rely on manual operation or complex mechanical devices, resulting in cumbersome and unstandardized procedures, insufficient component positioning accuracy, and a tendency to produce misalignment or displacement defects. Simultaneously, the high degree of manual involvement leads to continuously rising production costs and significantly extended production cycles, failing to meet the high efficiency and consistency requirements of modern electronic component manufacturing. Especially in mass production scenarios, existing methods struggle to achieve stable and reliable large-scale operations, severely restricting the production efficiency and product quality of voice coil motor bases. Summary of the Invention

[0003] The problem this invention addresses is: how to improve the production efficiency of voice coil motor bases.

[0004] To address the above problems, the present invention provides a method for manufacturing a base with integrated coils, comprising the following steps:

[0005] One-time basic forming: The first sheet is stamped to obtain a first basic sheet with a first preset circuit;

[0006] Injection Molding: The first base plate is placed into an injection mold, and plastic material is injected into the injection mold to form an initial encapsulation. The plate is then cut to obtain an injection molding preform.

[0007] Coil attachment: attaching ICs and coils to the qualified injection-molded preform;

[0008] Basic secondary forming: The second plate is stamped to obtain a second basic plate with a second preset circuit. The second basic plate is laser welded to the injection molding blank with IC and coil attached to it to form a blank semi-finished product.

[0009] Two-shot injection molding: The preform semi-finished product is bent into a preset shape and placed into a two-shot mold. The plastic material is injected into the two-shot mold to form a finished preform with complete plastic encapsulation. At least two plastic materials with different properties are injected into the two-shot mold sequentially or simultaneously. The first material is a high-rigidity structural layer, and the second material is an elastic buffer layer. The first material and the second material are fused together in the two-shot mold to form a layered composite encapsulation structure.

[0010] Optionally, attaching the IC includes the following steps:

[0011] Feeding process: The injection preform is precisely placed onto the carrier through a suction nozzle;

[0012] Soldering process: A fixed amount of solder paste is applied to the preset Pad position of the first preset circuit using a fully automatic vision soldering machine;

[0013] SPI process: The quality of the solder paste is inspected using solder paste inspection equipment;

[0014] Surface mount process: The TMR device is precisely mounted onto the solder paste using an SMT pick and place machine;

[0015] Reflow soldering process: The carrier is sent into a reflow oven and heated to melt the solder paste and form stable solder joints;

[0016] Material unloading process: The injection preform with the TMR device welded on it is taken out from the carrier and placed into a tray for temporary storage.

[0017] Optionally, attaching the coil includes the following steps:

[0018] Feeding process: Place the qualified IC-attached injection preform into the carrier tray, and load the coil packaged with customized carrier tape into the feed end of the chip mounter;

[0019] Bottom dispensing process: Apply fixing adhesive to the coil pre-attached position on the injection molding blank;

[0020] Coil attaching process: The coil is picked up by the suction nozzle and attached and cured;

[0021] Wire arrangement process: Arrange the tail wire of the coil to the corresponding Pad position;

[0022] Solder ball soldering process: Solder the tail wire to the Pad position;

[0023] Weld joint inspection procedure: Inspect for welding defects;

[0024] Intermediate dispensing process: Apply filler glue to the middle area of ​​the coil to enhance mechanical strength;

[0025] Solder joint adhesive application process: Apply protective adhesive to the solder joint to prevent oxidation;

[0026] Material feeding and baking process: The injection preform with coil attached is taken out from the carrier tray and the protective adhesive is completely cured by baking.

[0027] Optionally, the injection molding step specifically includes:

[0028] Injection molding and cutting: Multiple first base plates are placed into a injection mold, and plastic material is injected into the injection mold to complete the initial overmolding. Then, the intermediate product after the initial overmolding is cut to separate it into multiple independent units, each of which includes a first base plate.

[0029] Inspection process: The integrity of the plastic molding of the independent unit is checked by manual visual inspection, and the first base plate is free from deformation, plating defects or oxidation, so as to select qualified independent units as the injection molding preform.

[0030] Optionally, the injection molding second injection step is completed in an automated workstation, which includes a robot and a vision positioning system. The robot performs adaptive bending based on the posture information of the preform semi-finished product obtained by the vision positioning system, and puts the bent preform semi-finished product into the mold for secondary injection, so as to realize the connection between bending and injection molding.

[0031] Optionally, in the two-shot injection molding step, the two-shot mold is a multi-cavity dynamic injection mold, and the cavity structure of the multi-cavity dynamic injection mold can be adaptively adjusted according to the bending angle of the preform semi-finished product; and / or, the two-shot mold is provided with mechanical positioning pins or vacuum adsorption structures to fix the bent preform semi-finished product before injection to prevent displacement during the injection process.

[0032] Optionally, in the two-shot injection molding step, an inert gas is injected into the cavity of the two-shot mold at the same time as the plastic material is injected, so that the plastic material uniformly fills the cavity under the pressure of the inert gas and forms an internal air channel structure.

[0033] Optionally, in the injection molding second step, conductive particles are premixed into the plastic material or an electromagnetic shielding film is pre-laid on the surface of the preform before injection; and / or, during the injection process, an electrical test channel is reserved in the preform, the electrical test channel extending to the circuit pad area for probe access in subsequent electrical testing processes.

[0034] Compared with existing technologies, the coil-integrated base production method of the present invention obtains a first base plate with a hollowed-out area through a one-step base molding process. The hollowed-out area of ​​the first base plate facilitates subsequent injection molding of plastic materials. During the stamping process, the first base plate can serve as a carrier substrate for a first preset circuit and can form a support structure that matches the shape of the first preset circuit to ensure the geometric accuracy of the first preset circuit. This facilitates automatic injection molding using injection molding equipment, ensuring the injection quality of subsequent injection shots. The injection preform obtained through the injection shot step can further ensure the geometric accuracy of the first preset circuit using solidified plastic material. At the same time, the solidified plastic material in the injection preform forms a stable matrix, facilitating identification by the pick-and-place machine, ensuring the attachment quality of subsequent ICs and coils, and improving attachment efficiency. The preform semi-finished product obtained through the second-step base molding process ensures a stable connection between the second base plate and the injection preform, making the injection preform and the second base plate form an integral structure. In the subsequent second injection molding process, misalignment between the preform from the first injection and the second base plate is avoided, facilitating automated injection molding again and ensuring the injection quality of the second injection. Simultaneously, the second base plate maintains the geometry of the second pre-designed circuit, ensuring its stability during subsequent injection molding. The process of obtaining the preform through the second injection molding allows the plastic material to maintain the geometry of the second pre-designed circuit, achieving full coverage of both circuit structures. Furthermore, the solidification of the plastic material enables automatic connection with the preform semi-finished product, ensuring connection accuracy and stability. Thus, through the integrated design of staged stamping, injection molding, and bonding processes, the processing of each step ensures the quality of the next, forming a highly efficient and collaborative production process. This facilitates automated production, effectively eliminating the bottleneck of manual operation, improving production efficiency and positioning accuracy, and meeting the needs of mass production.

[0035] The present invention also provides a voice coil motor base, which adopts the base manufacturing method integrating the coil as described above.

[0036] This voice coil motor base has all the advantages of the manufacturing method of the base with integrated coil, which will not be elaborated here. Attached Figure Description

[0037] Figure 1 This is a schematic flowchart of the method for producing a base with integrated coils according to an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the first preset circuit, the second preset circuit, and the final coil shape in an embodiment of the present invention.

[0039] Figure 3This is a schematic diagram of the structure of a single pre-embedded semi-finished product and the first and second preset circuits in the single pre-embedded semi-finished product in an embodiment of the present invention.

[0040] Figure 4 This is a schematic diagram of the structure of a single pre-formed semi-finished product after bending and coil assembly in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the structure of a single finished preform in an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the structure of a single finished preform after cutting in an embodiment of the present invention.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1-First base plate; 2-Second base plate; 3-Injection molding preform; 4-Preform semi-finished product; 5-First preset circuit; 6-Second preset circuit; 7-Coil; 8-Finished preform. Detailed Implementation

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0046] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in sequences other than those illustrated or described herein.

[0047] Combination Figures 1 to 6 As shown, the present invention provides a method for manufacturing a base with an integrated coil, comprising the following steps:

[0048] Step 1: Basic one-time forming: The first plate is stamped to obtain the first basic plate 1 with the first preset circuit 5.

[0049] Specifically, the first plate uses SUS316HN1 plate as the base material. The SUS316HN1 plate is first leveled, cut, and the edge burrs are removed. Then, it is precisely fed into the mold by a high-speed precision punch press and the punch press feeding mechanism to press the first preset circuit 5 onto the first plate to form the first base plate 1. The first plate serves as the carrier substrate for the first preset circuit 5. Except for the frame and the part corresponding to the first preset circuit 5, the part of the first base plate 1 forms a hollow area to facilitate the subsequent plastic material to cover the first preset circuit 5 through the hollow area. In addition, the part of the first base plate 1 corresponding to the first preset circuit 5 can prevent the first preset circuit 5 from deforming to ensure the geometric accuracy of the first preset circuit 5.

[0050] Step 2: Injection Molding: Place the first base plate 1 into the injection mold, inject plastic material into the injection mold for initial encapsulation, and cut it to obtain the injection molding preform 3.

[0051] Specifically, the first base plate 1 is fixed in a first injection mold, and CM529BP plastic material is injected into the first injection mold using a horizontal injection molding machine. The CM529BP plastic material covers the first preset circuit 5 in the first base plate 1 using the hollow area of ​​the first base plate 1. After being heated and melted by the barrel, it is held under pressure for 5-10 seconds and then cooled. The first plastic part formed by the CM529BP plastic material can reinforce the first preset circuit 5 in the first base plate 1 and form a "base plate-plastic" composite preform with the first base plate 1, that is, the first overmolding. Then the first plastic part in the first overmolding is cut (the shape of the first plastic part is trimmed) to obtain the injection preform 3.

[0052] Step 3: Coil 7 Attachment: Attach the IC (integrated circuit) and coil 7 onto the qualified injection molding blank 3.

[0053] Specifically, after the initial overmolding process, a preform 3 is obtained through cutting. This preform 3 is then inspected, including visual inspection (checking for missing, overflowing, or cracked plastic; deformation of the base material; and peeling of the gold plating) and dimensional inspection (measuring key dimensions of the preform using calipers or micrometers, such as thickness 5.87mm). The criteria for acceptance are based on the product drawings: plastic defect area ≤0.1mm², terminal deformation ≤0.03mm, and dimensional deviation within ±0.05mm. Non-conforming products are marked and isolated. Then, ICs (integrated circuits) and coils 7 are attached to the qualified preform 3.

[0054] Step 4: Basic secondary forming: The second plate is stamped to obtain the second basic plate 2 with the second preset circuit 6. The second basic plate 2 is laser welded to the injection molding blank 3 with IC and coil 7 attached to it to form the blank semi-finished product 4.

[0055] Specifically, the pressing process of the second base plate 2 is similar to that of the first base plate 1, and the second base plate 2 also includes a hollowed-out area. For example... Figure 3 As shown, the second base plate 2 and the injection molding preform 3 are stacked together. The second base plate 2 is connected to the first base plate 1 of the injection molding preform 3. The first preset circuit 5 in the injection molding preform 3 and the second preset circuit 6 in the second base plate 2 are laser welded to form the preform semi-finished product 4.

[0056] Step 5: Combining Figure 4 and Figure 5 As shown, injection molding two-shot: the preform semi-finished product 4 is bent into a preset shape and placed into the two-shot mold, and plastic material is injected into the two-shot mold to form a complete plastic-encapsulated preform 8.

[0057] Specifically, a precision stamping and cutting machine is used to cut the unused strip around the perimeter of the initial semi-finished product 4. Then, a CNC bending machine is used to bend it according to the shape of the two-shot mold. During bending, the portion of the initial semi-finished product 4 containing the first preset circuit 5 is bent upwards, such as... Figure 4 As shown, to adapt the preform semi-finished product 4 to the mold cavity of the two-shot injection molding, CM529BP plastic material is injected into the mold cavity. The CM529BP plastic material covers the second preset circuit 6 of the preform semi-finished product 4. After the CM529BP plastic material solidifies, the second plastic body formed by the CM529BP plastic material can be integrally formed with the first plastic body in the preform semi-finished product 4, thereby achieving full coverage of the two preset circuit structures, as shown. Figure 5As shown, a preform 8 is formed to create a complete plastic encapsulation. In the two-shot injection molding step, at least two plastic materials with different properties are injected sequentially or simultaneously into the two-shot mold. The first material is a high-rigidity structural layer, and the second material is an elastic buffer layer. The first and second materials fuse within the two-shot mold to form a layered composite encapsulation structure. For example, the first material is a high-rigidity structural layer, which can be selected from engineering plastics such as glass fiber reinforced polycarbonate (PC+GF), polyphenylene sulfide (PPS), liquid crystal polymer (LCP), or high-strength nylon. These materials possess excellent dimensional stability and creep resistance. This layer typically constitutes the main skeleton or external load-bearing part of the encapsulation to ensure the overall structural integrity of the base. The second material is an elastic buffer layer, which can be selected from materials such as thermoplastic elastomer (TPE), silicone rubber, soft polyurethane (TPU), or ethylene-vinyl acetate copolymer (EVA). These materials can recover their original shape after being subjected to stress, effectively reducing stress concentration. This layer is typically used to encapsulate sensitive components, fill voids, or serve as a flexible interface to the outside, improving the product's impact resistance and comfort. For example, using sequential valve control or a multi-barrel injection molding machine, a second material is injected first to form a partial structure, followed by the injection of the first material for encapsulation or filling. Alternatively, the two materials can co-fill the cavity in a laminar flow within the mold, forming an inner and outer layer structure, i.e., injecting into different areas simultaneously through multiple gates. This allows the final encapsulation structure to integrate the advantages of multiple materials to meet complex functional requirements. Thus, by sequentially or simultaneously injecting at least two plastic materials with different properties and fusing them in a two-shot mold to form a layered composite encapsulation structure, the high-rigidity structural layer provides robust external support and an internal skeleton for the base integrating the coil 7, significantly enhancing its resistance to deformation and mechanical strength, effectively resisting external impacts and pressure. Meanwhile, the elastic buffer layer can absorb and disperse impact energy, providing effective shock absorption protection for internal precision components such as ICs and coil 7, reducing the risk of damage caused by vibration or drops. The formation of the layered composite packaging structure not only optimizes the distribution of material properties, enabling the base to maintain overall rigidity while possessing the necessary flexibility, but also ensures a tight bond between different material layers through integrated injection molding, avoiding the interface separation problem that may occur in traditional multi-part assembly. This significantly improves the durability, reliability, and long-term stability of the base integrating coil 7, extending the product's service life.

[0058] Therefore, in this embodiment, a first base plate 1 with a hollowed-out area can be obtained through the basic one-step molding process. The hollowed-out area of ​​the first base plate 1 facilitates the subsequent injection molding of plastic materials. During the stamping process, the first base plate 1 can serve as a substrate for the first preset circuit 5 and can form a support structure that matches the shape of the first preset circuit 5 to ensure the geometric accuracy of the first preset circuit 5. This facilitates automatic injection molding using injection molding equipment and ensures the injection quality of subsequent injection molding. The injection molding preform 3 obtained through the injection molding step can further ensure the geometric accuracy of the first preset circuit 5 using solidified plastic material. At the same time, the solidified plastic material in the injection molding preform 3 forms a stable matrix, which is convenient for the pick-and-place machine to identify, ensuring the subsequent bonding quality of IC and coil 7 and improving bonding efficiency. The preform semi-finished product 4 obtained through the basic two-step molding process can ensure the stable connection between the second base plate 2 and the injection molding preform 3, so that the injection molding preform 3 and the second base plate 2 form an integral structure, which is conducive to subsequent injection molding. During the second injection molding process, misalignment of the initial preform 3 and the second base plate 2 is avoided to facilitate automated injection molding using the injection molding equipment again, thereby ensuring the injection quality of the second injection. Simultaneously, the second base plate 2 maintains the geometry of the second preset circuit 6 to ensure its stability during subsequent injection molding. In the process of obtaining the finished preform 8 through the second injection molding, the plastic material maintains the geometry of the second preset circuit 6, achieving full coverage of the two preset circuit structures. Furthermore, the solidification of the plastic material allows for automatic connection with the preform semi-finished product 4, ensuring connection accuracy and stability. Thus, through the integrated design of staged stamping, injection molding, and bonding processes, the processing of each step ensures the quality of the next, forming a highly efficient and collaborative production process. This facilitates automated production using equipment, effectively eliminating the bottleneck of manual operation, improving production efficiency and positioning accuracy, and meeting the needs of mass production.

[0059] Optionally, attaching the IC (attaching the integrated circuit) includes the following steps:

[0060] Material loading process: The injection preform 3 is precisely placed onto the carrier through the suction nozzle.

[0061] Specifically, a carrier refers to a device capable of carrying and positioning workpieces. It can be implemented using a metal tray with precision positioning grooves or a platform with vacuum adsorption function. The carrier can be transported to different positions according to the process sequence via a conveyor structure. A fully automatic feeding machine can be used to grab the injection molding preform 3 through a vacuum nozzle and place it into the carrier with positioning grooves. The carrier provides a stable positioning reference for subsequent mounting and welding, ensuring positional consistency between processes.

[0062] Soldering process: A fixed amount of solder paste is applied to the preset Pad position (the metal contact point or area reserved on the voice coil motor assembly) of the first preset circuit 5 using a fully automatic vision soldering machine.

[0063] Specifically, a fully automatic vision-based soldering machine is used, equipped with a precision dispensing valve. The vision system identifies the preset Pad position (the metal contact point or area reserved on the voice coil motor assembly) of the first preset circuit 5, and applies a certain amount of solder paste to the Pad position (the metal contact point or area reserved on the voice coil motor assembly). The solder paste is a mixture of solder powder and flux, which provides a solder carrier for subsequent TMR soldering and ensures that the solder is evenly distributed during soldering.

[0064] SPI process (solder paste printing inspection): The quality of solder paste is inspected using solder paste inspection equipment;

[0065] Specifically, a 3DSPI inspection device (3D solder paste printing inspection device) is used to detect the height, area, and volume of solder paste on the Pad position (the metal contact point or area reserved on the voice coil motor assembly) after soldering using optical imaging technology. This process identifies defects such as insufficient solder, excessive solder, misalignment, and leaks, preventing poor soldering due to solder paste issues. Defective products trigger alarms, and rework is performed after manual review.

[0066] Surface mount technology (SMT) process: Using an SMT (Surface Mount Technology) pick-and-place machine (SMT) to precisely mount TMR (Tunnel Magnetoresistance) devices onto solder paste;

[0067] Specifically, an SMT (Surface Mount Technology) pick-and-place machine (SMT) is a high-precision surface mount equipment that uses a machine vision system to guide the placement head to achieve micron-level positioning, thereby ensuring the placement accuracy of TMR (Tunneling Magnetoresistive) devices. For example, a high-speed SMT pick-and-place machine uses dual-vision positioning (pick-and-place machine vision + carrier vision) to calibrate the position, precisely placing the TMR device onto the pad position (the reserved metal contact point or area on the voice coil motor assembly) after soldering, ensuring precise alignment of the TMR device's pins with the solder paste on the pad position (the reserved metal contact point or area on the voice coil motor assembly).

[0068] Reflow soldering process: The carrier is sent into the reflow oven and heated to melt the solder paste and form stable solder joints;

[0069] Specifically, a hot air reflow oven is used to melt the solder paste and wet the TMR device pins and Pad positions (the reserved metal contact points or areas on the voice coil motor assembly) through gradient heating. After cooling, the TMR pins and Pad positions (the reserved metal contact points or areas on the voice coil motor assembly) form metal solder joints, realizing the electrical conduction and mechanical fixation between the TMR and the circuit, avoiding the common problems of cold solder joints or solder bridging in manual soldering.

[0070] Material unloading process: The injection preform 3 with TMR device (electronic device supported by tunnel magnetoresistive effect) welded on is taken out from the carrier and placed into the tray for temporary storage.

[0071] Specifically, an automated unloading machine and a vacuum nozzle can be used to grab the injection preform 3 and place it into a tray with an antistatic coating (the tray has a groove that matches the product to prevent shaking). The tray is used to protect the product and prevent TMR damage during subsequent transportation, thus achieving the protection and standardized transfer of the finished product.

[0072] Thus, in the placement process, the introduction of SMT (Surface Mount Technology) placement machines (SMT) from the chip industry replaces manual placement with automated placement, improving placement accuracy, avoiding human error, shortening the production cycle, and reducing the labor cost per unit product, providing reliable technical support for the mass production of voice coil motor bases.

[0073] Optionally, attaching coil 7 includes the following steps:

[0074] Material loading process: Place the qualified IC (integrated circuit) preform 3 into the carrier tray, and load the coil 7 with customized carrier tape packaging onto the feeding end of the pick and place machine.

[0075] Specifically, a fully automatic feeding machine (same as IC (integrated circuit) mounting and feeding process) can be used. The fully automatic feeding machine uses a carrier tape feeder. The feeder drives the carrier tape through a servo motor to send the coils 7 one by one to the gripping position. The use of carrier tape can avoid the tail wire of the coils 7 being too long.

[0076] Bottom adhesive application process: Apply fixing adhesive to the pre-set attachment position of the coil 7 on the injection molding blank 3.

[0077] Specifically, a fully automatic vision dispensing machine can be used to apply fixing adhesive to the preset attachment position of the coil 7. The fixing adhesive can initially fix the coil 7, prevent the coil 7 from shifting during subsequent wire arrangement and soldering, and at the same time provide basic mechanical support for the coil 7.

[0078] Coil 7 attachment process: The coil 7 is picked up by the suction nozzle and attached and cured.

[0079] Specifically, the shape of the nozzle is adapted to the shape of the coil 7. For example, a round nozzle is used for a round coil 7, and a contour nozzle is used for an irregularly shaped coil 7. The coil 7 can be picked up from the carrier tape by the nozzle equipped on the SMT pick-and-place machine (electronic component placement machine), attached to the dispensing position and initially cured, avoiding deformation or damage to the coil 7.

[0080] Wire management process: Straighten the tail wire of coil 7 to the corresponding Pad position (the metal contact point or area reserved on the voice coil motor assembly).

[0081] Specifically, a fully automatic wire management mechanism is used to comb the tail wire (such as conductive pin) of coil 7 to the corresponding circuit Pad position (the reserved metal contact point or area on the voice coil motor assembly), ensuring that the tail wire is aligned with the Pad position (the reserved metal contact point or area on the voice coil motor assembly), providing a conductive foundation for subsequent solder ball soldering, and avoiding the tail wire from tangling or deviating.

[0082] Solder ball soldering process: Solder the tail wire to the Pad position (the reserved metal contact point or area on the voice coil motor assembly).

[0083] Specifically, using a semi-automatic solder ball soldering machine, the steps are as follows: ① Solder ball supply (feeding φ0.2-0.3mm solder balls to the junction of the tail wire and the Pad position (the reserved metal contact point or area on the voice coil motor assembly); ② Heating and soldering (using a hot air gun or laser to heat at a temperature of 230-250℃, melting the solder balls and wrapping them around the tail wire and the Pad position (the reserved metal contact point or area on the voice coil motor assembly)); ③ Cooling (natural cooling for 5-10 seconds to form a solder joint); the soldering shielding gas is nitrogen (oxygen content ≤300ppm). Using solder balls as solder, the tail wire of coil 7 and the Pad position (the reserved metal contact point or area on the voice coil motor assembly) are soldered and connected. Solder ball soldering is more suitable for single-point, small-area soldering (such as the thin tail wire of coil 7), resulting in small solder joints with good conductivity.

[0084] Weld joint inspection procedure: Inspect welding defects.

[0085] Specifically, 2D vision inspection equipment can be used to automatically identify the outline of the solder joint and compare it with standard solder joint parameters (such as diameter 0.3-0.4mm, no voids). After marking the defective products, manual resoldering can be performed. This can detect whether there are defects such as "missed solder, cold solder, bridging, solder joint too large / too small" in the solder ball solder joint, ensuring the electrical conductivity and mechanical reliability of coil 7 and the circuit.

[0086] Intermediate dispensing process: Apply filler glue to the middle area of ​​coil 7 to enhance mechanical strength.

[0087] Specifically, a fully automatic dispensing machine equipped with a long-needle dispensing valve can be used. The adhesive type is high-strength epoxy, and the dispensing amount is set according to the volume of coil 7 to ensure that the adhesive covers more than 50% of the surface area of ​​coil 7. The adhesive has the effect of enhancing the overall mechanical strength of coil 7, resisting the external impact of subsequent processes (such as bending and secondary injection), and preventing coil 7 from loosening or deforming.

[0088] Solder joint adhesive application process: Apply protective adhesive to the solder joint to prevent oxidation.

[0089] Specifically, a dispensing machine can be used with a micro dispensing valve. The adhesive can be a UV-curable conformal adhesive (which has waterproof, dustproof, and anti-oxidation properties after curing). The amount of adhesive dispensed should be controlled to just cover the solder joint. After dispensing, the adhesive should be cured by irradiating it with a UV lamp for 10-20 seconds. The protective adhesive isolates the solder joint from air and moisture, preventing oxidation and rust, while further reinforcing the solder joint and preventing vibration from causing it to fall off.

[0090] Material feeding and baking process: The injection molded blank 3 with coil 7 attached is taken out from the carrier tray and baked to completely cure the protective adhesive.

[0091] Specifically, an automated unloading machine can be used to pick up the product and place it into a tray. A constant temperature oven is used for baking, and the temperature and baking time are adjusted according to the adhesive curing parameters to ensure that all adhesives (bottom fixing adhesive, middle filling adhesive, and solder joint protection adhesive) are completely cured.

[0092] Thus, the feeding process, based on the qualified IC mounting preform 3, precisely places it into the automated carrier tray and supplies the coil 7 with customized carrier tape packaging, ensuring the initial positioning consistency between the preform and the coil 7. Subsequently, the bottom dispensing process applies fixing adhesive at preset positions, providing a stable initial adhesion base for the coil 7. The coil 7 mounting process uses a suction nozzle to pick up the coil 7 and achieve mounting and curing, utilizing the high repeatability of automated equipment to ensure the accuracy of coil 7 placement. The wire arrangement process and the solder ball soldering process work together to ensure the precise alignment of the coil 7 tail wire with the circuit pads and form a stable electrical path. The solder joint inspection process promptly identifies and corrects potential problems, improving the overall process's fault tolerance. The intermediate dispensing process and the solder joint dispensing process respectively enhance the overall mechanical strength of the coil 7 structure and the service life of the electrical connections. Finally, the unloading and baking process ensures complete cross-linking of the adhesive, bringing the product to a stable final state. These interconnected processes together construct a high-precision, high-efficiency automated mounting process, significantly improving the feasibility of mass production and product reliability.

[0093] Optionally, the injection molding process specifically includes:

[0094] Injection molding and cutting: Multiple first base plates 1 are placed into a injection mold, and plastic material is injected into the injection mold to complete the initial overmolding. Then, the intermediate product after the initial overmolding is cut to separate it into multiple independent units, each of which includes a first base plate 1.

[0095] Specifically, after the initial overmolding is completed in one injection molding cycle, the intermediate product in continuous strip form is cut into multiple independent units. This can be achieved using high-precision cutting equipment, such as laser cutters or mechanical punching equipment, to separate multiple independent units in a timely manner, avoiding the risk of deformation due to insufficient overall rigidity of the strip, thereby providing a stable physical reference for subsequent IC (integrated circuit) and coil 7 attachment.

[0096] Inspection process: The integrity of the plastic molding of the independent unit is checked by manual visual inspection. The first base plate 1 is free from deformation and plating defects or oxidation. Qualified independent units are selected as injection molding preforms 3.

[0097] Specifically, inspection can be conducted using a combination of visual inspection and auxiliary tools, such as magnifying glasses or microscopes, to accurately identify minute defects, such as insufficient plastic material, warped terminals, or abnormal plating. This allows for the early rejection of defective products (such as plastic defects or deformed terminals), achieving early interception of defects and preventing them from flowing into subsequent processes and causing cost waste.

[0098] Thus, by placing multiple first base plates 1 into a single injection mold and injecting plastic material into the mold to complete the initial overmolding, and then cutting the intermediate product after the initial overmolding, transforming it from a continuous strip into multiple independent units, this operation not only avoids the positioning accuracy problems caused by strip stress interference but also provides a stable operating object for subsequent processes. The inspection process relies on the independent unit form formed after cutting, allowing the inspected object to be freed from the strip's constraints and present a complete, visible surface. This enables accurate identification of potential defects, improves the efficiency of quality screening in the production process, reduces the risk of rework, and optimizes production cycle time and resource utilization.

[0099] Optionally, the injection molding second injection step is completed in an automated workstation, which includes a robot and a vision positioning system. The robot performs adaptive bending based on the posture information of the preform semi-finished product obtained by the vision positioning system, and puts the bent preform semi-finished product into the mold for secondary injection, so as to realize the connection between bending and injection molding.

[0100] Specifically, the robot can be a multi-axis industrial robot, such as a six-axis articulated robot. The robot's end effector is used to grasp and bend the initial semi-finished product 4. The vision positioning system can be a 2D vision system or a 3D vision system (such as structured light or stereo vision). For example, images of the initial semi-finished product 4 are captured by optical sensors (such as industrial cameras), and image processing algorithms are used to analyze the image data to accurately calculate the position (X, Y, Z coordinates) and attitude (such as pitch, yaw, and roll angles) of the initial semi-finished product 4 in three-dimensional space.

[0101] The robot can dynamically adjust its bending path and motion parameters based on the posture information of the pre-formed semi-finished product 4 acquired in real time, in order to compensate for minor deviations in the placement or shape of the pre-formed semi-finished product 4 and ensure the accuracy and consistency of each bend.

[0102] Through data interaction between the robot control system and the vision system, the path of the initial preform 4 can be corrected online or the parameters can be dynamically adjusted. After bending, the robot precisely places the bent initial preform 4 into the cavity of the secondary injection mold for subsequent secondary injection molding. That is, the bending operation of the initial preform 4 is seamlessly connected with the subsequent injection molding operation, forming a continuous and efficient production process.

[0103] In this way, the visual positioning system captures the posture information of the initial semi-finished product 4 in real time, enabling the robot to perform adaptive bending based on this information, thereby avoiding positioning deviations and offset defects caused by manual operation. The robot then precisely places the bent initial semi-finished product 4 into the mold for secondary injection. This process seamlessly connects the bending and injection steps, reducing pauses and errors in intermediate stages and improving overall production efficiency and process continuity. Thus, the introduction of the automated workstation achieves automated control of the entire injection molding process, reducing manual intervention and ensuring high consistency and stability in mass production, thereby significantly improving the automation and intelligence level of the production process.

[0104] Optionally, in the two-shot injection step, the two-shot mold is a multi-cavity dynamic injection mold, and the cavity structure of the multi-cavity dynamic injection mold can be adaptively adjusted according to the bending angle of the preform semi-finished product 4; and / or, the two-shot mold is provided with mechanical positioning pins or vacuum adsorption structures to fix the bent preform semi-finished product 4 before injection to prevent displacement during injection.

[0105] Specifically, the cavities of multi-cavity dynamic injection molds can adopt a modular design, allowing different bending angles to be adapted by replacing or adjusting different cavity modules; or, the cavities can integrate movable parts, such as sliders, ejector pins, or deformable walls, which can be precisely controlled by an external drive system (such as hydraulic, pneumatic, or servo motors) to achieve dynamic adjustment of the cavity shape.

[0106] Adaptive adjustment of the cavity structure refers to the ability of the mold cavity to automatically or semi-automatically change its internal shape according to the actual bending angle of the preform 4 to be injected, ensuring a tight fit between the mold cavity and the preform 4 and eliminating gaps. For example, a precision adjustment mechanism driven by a servo motor can be integrated into the mold cavity. This mechanism can precisely move the cavity wall or internal inserts according to the bending angle of the preform 4 detected by a vision system or preset parameters, thereby changing the geometry of the cavity. Another approach is to use a hydraulically or pneumatically driven flexible cavity wall. By controlling the fluid pressure, the cavity wall deforms to adapt to the contour of the preform 4.

[0107] Alternatively, a mechanical locating pin or a vacuum adsorption structure can be provided in the two-shot mold. A mechanical locating pin is a device that restricts the position of the workpiece through physical contact. Its function is to precisely fix the bent preform 4 in a predetermined position within the mold cavity before injection molding, preventing it from moving due to injection pressure or vibration during the injection process. Mechanical locating pins can take various forms; for example, they can be tapered pins fixed to the mold, achieving positioning by engaging with pre-drilled holes or feature structures on the preform 4; or they can be retractable spring pins or pneumatic pins that automatically extend to fix the preform 4 after it is placed in position and automatically retract after injection molding to facilitate product removal.

[0108] The vacuum adsorption structure functions similarly to mechanical positioning pins, ensuring the stability of the bent preform 4 during injection molding. The vacuum adsorption structure can include a microporous array integrated into the mold cavity wall, creating negative pressure on the surface of the preform 4 by drawing a vacuum, thus firmly adsorbing it onto the mold surface; alternatively, independent vacuum suction cups can be used. These suction cups are activated after the preform 4 is placed, generating suction through a vacuum pump to fix it in place.

[0109] Thus, in the two-shot injection molding process, a multi-cavity dynamic injection mold is used. Its cavity structure can adaptively adjust according to the actual bending angle of the preform 4, ensuring precise matching between the mold cavity and the bent preform 4, effectively avoiding positioning deviations caused by shape differences. Simultaneously, mechanical positioning pins or vacuum adsorption structures are installed in the two-shot mold to reliably fix the bent preform 4 before injection, effectively preventing displacement caused by plastic injection pressure or mold vibration during injection. In this way, the synergistic effect of the multi-cavity dynamic injection mold and the mechanical positioning pins or vacuum adsorption structures improves the positioning accuracy and stability of the preform 4 during injection molding, ensuring the uniformity and integrity of the plastic encapsulation, thereby improving product quality consistency and production efficiency.

[0110] Optionally, in the two-shot injection step, an inert gas is injected into the cavity of the two-shot mold at the same time as the plastic material is injected, so that the plastic material is uniformly filled into the cavity under the pressure of the inert gas and forms an internal air channel structure.

[0111] Specifically, during inert gas injection, gas injection ports can be installed in the nozzle or mold runner of the injection molding machine, working in conjunction with the plastic injection port. By precisely controlling the timing, pressure, and flow rate of the gas injection, it can be ensured that the gas enters the cavity simultaneously with or immediately after the plastic material. Alternatively, a special two-component injection head can be used, with one channel for the plastic material and the other for the inert gas. The two are mixed or propelled synergistically before entering the mold cavity or in the initial stage of entry. This creates a uniform pressure field within the cavity, pushing the plastic material to all corners of the cavity, especially thin-walled areas or locations far from the gate, thus ensuring that the plastic material fully reaches and fills the entire cavity. Furthermore, inert gas can also act as an "internal support," compensating for the shrinkage of the plastic material as it cools and shrinks by continuously applying pressure, reducing internal stress, and preventing product deformation.

[0112] Internal gas channel structures can be designed as channels that run throughout the entire interior of the product, for example, to allow wires or optical fibers to pass through, or to form a honeycomb structure to improve the strength-to-weight ratio, or to serve as heat dissipation channels to dissipate internal heat. Internal gas channel structures can be used to reduce product weight, save materials, improve heat dissipation performance, or provide pathways for subsequent functional integration. For example, by precisely controlling the injection volume, injection pressure, and holding time of inert gas, continuous or discontinuous channels can be formed within the plastic material. The shape and position of these channels can be optimized according to mold design and product functional requirements.

[0113] Thus, in the second injection molding process, inert gas is injected into the cavity of the second injection mold simultaneously with the injection of plastic material. The pressure of the inert gas effectively assists the flow and filling of the plastic material within the complex cavity, ensuring uniform distribution and preventing defects caused by insufficient filling. Furthermore, by forming an internal air channel structure, the structural performance of the product can be further optimized, such as reducing product weight, saving material, or facilitating subsequent functions like heat dissipation and wiring. This enhances the overall quality and functionality of the coil-integrated base. Consequently, higher quality and more reliable plastic encapsulation can be achieved in the secondary encapsulation stage, ensuring the stability and durability of the voice coil motor base and improving the integrity and consistency of the encapsulation.

[0114] Optionally, in the injection molding second step, conductive particles are premixed into the plastic material or an electromagnetic shielding film is pre-laid on the surface of the preform 4 before injection; and / or, during the injection process, an electrical test channel is reserved in the preform 4, extending to the circuit pad area, for probe access in subsequent electrical testing processes.

[0115] Specifically, conductive particles refer to tiny particles with conductive properties, such as metal powders (e.g., copper powder, nickel powder, silver powder) or carbon-based materials (e.g., graphite, carbon nanotubes, graphene). By pre-mixing these conductive particles into plastic materials, the plastic materials themselves can acquire a certain degree of conductivity, thereby forming an encapsulation structure with electromagnetic shielding function after injection molding. For example, in the injection molding machine hopper or mixing device, plastic granules and conductive particles are physically mixed in a certain proportion and then fed into the injection molding machine for injection. This method is suitable for scenarios where the requirement for uniformity of conductive particle distribution is relatively low, or where conductive particles are easily dispersed.

[0116] Electromagnetic shielding film is a thin film material with good conductivity and shielding effectiveness. It is usually composed of a metal layer or a conductive polymer layer and is used to block the propagation of electromagnetic waves and reduce electromagnetic interference. For example, after the initial semi-finished product 4 is bent and before it is placed into the second-shot mold, a pre-cut electromagnetic shielding film is precisely attached to a specific surface area of ​​the initial semi-finished product 4 by an automated device. The attachment method can be pressure-sensitive adhesive bonding or hot melt adhesive bonding; or, a metal or conductive polymer film is formed on the surface of the initial semi-finished product 4 by spraying conductive coating (such as conductive paint) or by vacuum coating (such as magnetron sputtering, evaporation coating) as an electromagnetic shielding layer.

[0117] In another embodiment, the electrical test channel refers to a path pre-reserved within or on the surface of the plastic material during the plastic encapsulation process, through mold design or auxiliary structures, allowing test probes to contact the internal circuit pads. For example, a retractable or detachable core is designed in the two-shot mold. During injection molding, these cores occupy predetermined channel positions, and the plastic material flows around the core. After injection molding, the core is extracted, thus forming a test channel penetrating the plastic layer. Alternatively, before injection molding, an insert made of easily removable material (such as a soluble material, a low-melting-point material, or a mechanically removable material) is placed on the pre-formed semi-finished product 4 at the location where the channel needs to be reserved. After injection molding, the insert is removed by dissolving, heating to melt, or mechanically removing the insert, forming the test channel. The end of the electrical test channel can be precisely aligned and contacted with the circuit pad area on the pre-formed semi-finished product 4, so that the test probes can reliably make electrical connections. For example, when designing a two-shot mold, the positioning accuracy of its core or insert is precisely matched with the circuit pad area on the initial semi-finished product 4. Through the precision machining and assembly of the mold, the alignment of the channel with the pad is ensured.

[0118] Thus, in the second injection molding step, by premixing conductive particles into the plastic material or pre-laying an electromagnetic shielding film on the surface of the preform semi-finished product 4, the final plastic encapsulation structure possesses electromagnetic shielding functionality, effectively blocking the influence of external electromagnetic interference on the internal circuitry, thereby improving the product's electromagnetic compatibility and reliability. Furthermore, by reserving electrical test channels during the injection molding process and extending them to the circuit pad area, convenient and reliable probe access points are provided for subsequent electrical testing processes. This avoids testing difficulties caused by encapsulation obstruction in traditional methods, simplifies the testing process, reduces manual intervention and operational complexity, and significantly improves production efficiency and testing accuracy. These improvements work synergistically to ensure that electromagnetic protection and testing convenience are balanced while forming a complete plastic encapsulation, thereby optimizing the overall production reliability and efficiency of the voice coil motor base.

[0119] Optionally, combined Figure 6 As shown, after the injection molding process, there is also a cutting process, which includes using cutting equipment to remove the unused material strip around the finished preform 8 to facilitate batch tray operation.

[0120] Specifically, such as Figure 6 As shown, a CNC engraving machine can be used to remove the plastic overflow and other unused material around the product after two-shot engraving, so that the product size meets the final design specifications.

[0121] Thus, by removing the unused material strip around the finished preform 8 using a cutting device after the second injection molding step, batch tray loading is facilitated, ensuring the stability and reliability of the material strip removal process and avoiding positioning deviations and inefficiencies that may occur with manual operation. Furthermore, removing the unused material strip around the finished preform 8 directly eliminates the interference of the material strip on the product's physical boundaries, allowing each finished preform 8 to exist independently. This supports the rapid positioning and orientation adjustment of the finished preform 8 by the subsequent automated carrier, improving the smoothness and throughput of the tray loading process, reducing waiting time between processes, and promoting the optimization of the production process towards high efficiency and automation.

[0122] Building upon this, the cutting process works closely with other steps in the aforementioned production method for the coil-integrated base. For example, after the second injection molding, the cutting process can quickly separate the finished preform 8 from the overall structure, providing a standardized, independent unit for the subsequent tray-stacking process. Simultaneously, it lays the foundation for batch operations in subsequent electrical testing and inspection processes, thereby further improving overall production efficiency and consistency.

[0123] Optionally, the production method of the base with integrated coils also includes a tray placement process, which includes placing the cut finished blank 8 into the tray in a preset direction to facilitate batch operation of subsequent electrical testing and inspection processes.

[0124] Specifically, after the cutting process is completed, although the finished preform 8 has been separated into independent units, its orientation is not determined. If it directly enters the electrical testing or inspection process, it may require additional adjustment time due to inconsistent orientation.

[0125] A fully automatic tray-loading machine can be used, equipped with a vacuum nozzle to grab the finished blank 8 and place the product into a tray with a positioning groove (the tray material is anti-static PP). This ensures that the cut finished blank 8 is placed into the tray in a "uniform direction" (such as the Pad position (the metal contact point or area reserved on the voice coil motor assembly) facing the same direction), which facilitates subsequent batch operations for electrical testing and inspection.

[0126] Thus, by introducing the tray placement process, the finished pre-formed blanks (8) are uniformly placed in a preset orientation, enabling automated equipment to quickly identify and operate them. This avoids repetitive positioning or manual intervention, improving the smoothness of process transitions and significantly reducing production cycles and labor costs, thereby effectively supporting the continuity and reliability of mass production. Simultaneously, the tray placement and cutting processes complement each other, jointly optimizing the overall production flow and further meeting the needs of automated production.

[0127] Optionally, the electrical testing process includes connecting the circuit of the finished preform 8 to a testing tool and detecting the circuit parameters to ensure that the finished preform 8 transmits electrical signals.

[0128] Specifically, electrical testing refers to electrical performance testing. A test fixture is used to connect to the product's circuitry to check parameters such as continuity, resistance, and insulation. This process identifies electrical defects such as open circuits, short circuits, and poor connections, ensuring the product can transmit electrical signals normally. For example, a fully automatic electrical testing machine can be used, with a probe fixture (the probes correspond to the Pad position on the product (the pre-reserved metal contact point or area on the voice coil motor assembly), with a contact resistance ≤10mΩ). Test items may include: ① Continuity test (continuity of critical circuit paths, continuity resistance ≤5Ω is acceptable); ② Insulation test (insulation resistance between the circuit and the plastic substrate ≥100MΩ, test voltage 500VDC); ③ Functional test (if the product has a Hall element, the signal output must be tested for normal operation). During testing, the test tray is automatically fed into the fully automatic electrical testing machine, the probe fixture contacts the Pad position (the pre-reserved metal contact point or area on the voice coil motor assembly), the testing machine automatically collects data and compares it with standard values. Qualified products are marked "OK," and unqualified products are marked "NG" and ejected.

[0129] Thus, a high-precision connection is first established between the testing tool and the circuit of the pre-finished blank 8. This process ensures the stability of the contact and the accuracy of the positioning, thereby avoiding common problems such as poor contact or deviation in manual operation. Subsequently, by testing the circuit parameters, the electrical performance of the pre-finished blank 8 is quantitatively evaluated. Products with abnormal transmission functions are promptly identified and eliminated. This ensures that each pre-finished blank 8 can reliably transmit electrical signals during batch processing. Combined with the tray placement process, this significantly improves the efficiency and reliability of batch operations, solves the problem of inaccurate circuit function verification, and provides a solid guarantee for subsequent quality control.

[0130] Optionally, the inspection process includes checking the appearance and dimensions of the pre-finished blank 8 that has passed the electrical test, in order to select the finished products that meet the quality standards.

[0131] Specifically, since electrical testing has confirmed that the circuit functions normally, this inspection process focuses on identifying physical defects, avoiding the waste of resources on ineffective inspections of functionally defective products, thereby optimizing the targeting and efficiency of the inspection process. For example, visual inspection may include manual inspection of the product under a backlit inspection table, requiring: no scratches, cracks, or excess glue on the plastic surface; no exposed or oxidized solder joints; and no loosening or deformation of coil 7. Dimensional inspection may include sampling and testing of key dimensions of the product using a coordinate measuring machine (e.g., length 17.67mm, thickness 5.87mm). Mechanical performance inspection may also be included: sampling for vibration and drop tests, after which the product shows no structural damage and normal electrical performance.

[0132] In this way, by inspecting the specific contents of the inspection process, the appearance and size of the finished pre-form 8 that has passed the electrical test are checked, which achieves efficient and accurate quality screening. Combined with the traying process, it can significantly improve the efficiency of batch operation and provide quality assurance for the subsequent vacuum packaging and shipping processes.

[0133] Optionally, the injection molding process also includes electroplating the first base plate 1 before placing it into the injection mold. Specifically, a fully automated rack plating production line is used, and an acidic gold plating process is employed to electroplat the first base plate 1. The specific steps are: workpiece degreasing (removing residual oil from stamping) → pickling (removing the surface oxide layer) → activation (enhancing surface adsorption capacity) → gold plating (electrolytic deposition of a gold layer) → post-treatment (cleaning and drying). The gold layer thickness is measured using an X-ray fluorescence thickness gauge to ensure that there are no missed plating or pinholes in the Pad area (circuit soldering area) to ensure that the surface has good solderability.

[0134] Another embodiment of the present invention provides a voice coil motor base, which adopts the base manufacturing method integrating the coil as described above.

[0135] This voice coil motor base has all the advantages of the manufacturing method of the base with integrated coil, which will not be elaborated here.

[0136] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A method for producing a base with integrated coils, characterized in that, Includes the following steps: One-time basic forming: The first plate is stamped to obtain the first basic plate (1) with the first preset circuit (5); Injection molding: The first base plate (1) is placed into the injection mold, and plastic material is injected into the injection mold to form the initial encapsulation. The material is then cut to obtain the injection molding preform (3). Coil attachment: attach IC and coil (7) to the qualified injection preform (3). Basic secondary molding: The second plate is stamped to obtain a second basic plate (2) with a second preset circuit (6). The second basic plate (2) is laser welded to the injection molding blank (3) with IC and coil attached to it to form a blank semi-finished product (4). Two-shot injection molding: The preform semi-finished product (4) is bent into a preset shape and placed into a two-shot mold. The plastic material is injected into the two-shot mold to form a finished preform (8) with complete plastic encapsulation. At least two plastic materials with different properties are injected into the two-shot mold sequentially or simultaneously. The first material is a high-rigidity structural layer and the second material is an elastic buffer layer. The first material and the second material are fused in the two-shot mold to form a layered composite encapsulation structure.

2. The method for producing a base with an integrated coil according to claim 1, characterized in that, The process of attaching the IC includes the following steps: Feeding process: The injection preform (3) is precisely placed onto the carrier through the suction nozzle; Soldering process: A fixed amount of solder paste is applied to the preset Pad position of the first preset circuit (5) by a fully automatic vision soldering machine; SPI process: The quality of the solder paste is inspected using solder paste inspection equipment; Surface mount process: The TMR device is precisely mounted onto the solder paste using an SMT pick and place machine; Reflow soldering process: The carrier is sent into a reflow oven and heated to melt the solder paste and form stable solder joints; Material unloading process: The injection preform (3) with the TMR device welded on it is taken out from the carrier and placed into the tray for temporary storage.

3. The method for producing a base with an integrated coil according to claim 1, characterized in that, The process of attaching the coil includes the following steps: Feeding process: Place the qualified IC-attached injection preform (3) into the carrier tray, and load the coil (7) packaged with customized carrier tape into the feed end of the chip mounter; Bottom dispensing process: Apply fixing adhesive to the coil pre-attached position on the injection molding blank (3); Coil attaching process: The coil (7) is picked up by the suction nozzle and attached and cured; Wire arrangement process: Arrange the tail wire of the coil (7) to the corresponding Pad position; Solder ball soldering process: Solder the tail wire to the Pad position; Weld joint inspection procedure: Inspect for welding defects; Intermediate dispensing process: Apply filler glue to the middle area of ​​the coil (7) to enhance mechanical strength; Solder joint adhesive application process: Apply protective adhesive to the solder joint to prevent oxidation; Material feeding and baking process: The injection molding blank (3) with the coil (7) attached is taken out from the carrier plate and the protective adhesive is completely cured by baking.

4. The method for producing a base with integrated coils according to claim 1, characterized in that, The injection molding process specifically includes: Injection molding and cutting: Multiple first base plates (1) are placed into a injection mold, and plastic material is injected into the injection mold to complete the initial overmolding. Then, the intermediate product after the initial overmolding is cut to separate it into multiple independent units, each of which includes one first base plate (1). Inspection process: The plastic molding integrity of the independent unit is checked by manual visual inspection, and the first base plate (1) is free from deformation and plating defects or oxidation, so as to select qualified independent units as the injection molding preform (3).

5. The method for producing a base with an integrated coil according to claim 1, characterized in that, The injection molding second injection step is completed in an automated workstation, which includes a robot and a vision positioning system. The robot performs adaptive bending based on the posture information of the preform semi-finished product (4) obtained by the vision positioning system, and puts the bent preform semi-finished product (4) into the mold for secondary injection, so as to realize the connection between bending and injection molding.

6. The method for producing a base with an integrated coil according to claim 1, characterized in that, In the two-shot injection step, the two-shot mold is a multi-cavity dynamic injection mold, and the cavity structure of the multi-cavity dynamic injection mold can be adaptively adjusted according to the bending angle of the preform semi-finished product (4); and / or, the two-shot mold is provided with mechanical positioning pins or vacuum adsorption structures to fix the preform semi-finished product (4) after bending before injection, so as to prevent displacement during the injection process.

7. The method for producing a base with an integrated coil according to claim 1, characterized in that, In the two-shot injection molding step, an inert gas is injected into the cavity of the two-shot mold at the same time as the plastic material is injected, so that the plastic material fills the cavity evenly under the pressure of the inert gas and forms an internal air channel structure.

8. The method for producing a base with an integrated coil according to claim 1, characterized in that, In the injection molding two-shot step, conductive particles are premixed in the plastic material or an electromagnetic shielding film is pre-laid on the surface of the preform semi-finished product (4) before injection; and / or, during the injection process, an electrical test channel is reserved in the preform semi-finished product (4), the electrical test channel extending to the circuit pad area for probe access in subsequent electrical testing processes.

9. A voice coil motor base, characterized in that, The method for producing a base with an integrated coil as described in any one of claims 1-8 is adopted.

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