Transformer convenient for automatic surface mounting

Abstract

The invention belongs to the technical field of electronic equipment, and discloses a transformer convenient for automatic surface mounting, which comprises a magnetic core, a framework, a coil and a surface mounting assembly, the framework is arranged in the magnetic core in a penetrating manner; the coil sleeves the framework, and a second adhesive tape is arranged outside the coil; the surface mounting assembly is provided with a first plane and a second plane which are opposite, the surface mounting assembly is matched with the framework in an inserted mode and at least partially embedded in the framework so that the first plane can be attached to the second adhesive tape face, and the second plane is used for automatic surface mounting. Therefore, when the transformer is subjected to automatic surface mounting, Case does not need to be arranged, the surface mounting assembly is partially embedded in the framework, and the first plane and the second adhesive tape form surface fitting, so that on one hand, the flatness and the parallelism of the second plane meet the requirements of automatic surface mounting, and automatic surface mounting can be conveniently and smoothly completed; and therefore, the overall size of the transformer is smaller, the cost is lower, and the improvement of the transformer conforms to the development concepts of miniaturization and low cost in the industry.

Description

Technical Field

[0001] This invention relates to the field of electronic equipment technology, and more particularly to transformers that facilitate automated surface mount technology (SMT). Background Technology

[0002] With the continuous innovation of electronic technology and the in-depth promotion of the concept of intelligent manufacturing, the EE type wound transformer, as a core component in circuits such as power conversion and signal coupling, directly affects the manufacturing process of the whole product in terms of its production efficiency and adaptability.

[0003] Reference Figure 1 In the existing technology, in order to meet the requirements of automated patch placement equipment for transformer positioning accuracy and structural standardization, a solution of adding a plastic shell (Case10) to the top of the transformer is generally adopted. Case10 is usually fixed to the top of the transformer frame 2 by clips or adhesives, and its outer top wall is used for automated patch placement.

[0004] However, the introduction of Case 10 directly increased the manufacturing cost of transformers, and the overall size of the transformers would also increase significantly after Case 10 was added, which conflicted with the industry's development concept of miniaturization and low cost. Summary of the Invention

[0005] The purpose of this invention is to provide a transformer that facilitates automated chip mounting, which solves the problem that in the prior art, transformers need to be fitted with a case to achieve automated chip mounting, resulting in increased size and cost, which does not conform to the industry's development concept of miniaturization and low cost.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] This invention provides a transformer that facilitates automated surface mount technology (SMT) assembly, comprising:

[0008] A magnetic core, the magnetic core having a first adhesive tape on its exterior;

[0009] The skeleton is inserted inside the magnetic core;

[0010] A coil is fitted onto the frame, and the coil has a second adhesive tape on its exterior;

[0011] A patch assembly having a first plane and a second plane facing away from each other, the patch assembly being inserted into and at least partially embedded in the skeleton such that the first plane is in contact with the second tape surface, the second plane being used for automated patching.

[0012] Optionally, the patch assembly includes:

[0013] A patch plate is placed above the skeleton and has the first plane and the second plane.

[0014] Optionally, the patch assembly further includes: a limiting portion disposed on the patch plate and inserted into the skeleton; and / or, a plurality of limiting portions are disposed at intervals.

[0015] Optionally, the limiting part is plate-shaped, and one limiting part is provided on each side of the patch plate.

[0016] Optionally, at least one end of the limiting portion protrudes from the patch plate and forms an insertion portion, and the skeleton has an insertion groove that engages with the insertion portion.

[0017] Optionally, the side of the plug portion is in contact with the side wall of the plug groove.

[0018] Optionally, the top of the skeleton has a mounting slot for mounting the patch plate.

[0019] Optionally, the side of the patch plate is in surface contact with the wall of the mounting groove.

[0020] Optionally, the top wall of the patch plate is lower than or flush with the top wall of the skeleton.

[0021] Optionally, the patch plate and the limiting part are integrally formed.

[0022] The beneficial effects of this invention are:

[0023] By inserting a surface mount assembly (SMA) into the transformer, with the SMA at least partially embedded in the frame, and ensuring that the first plane and the second adhesive tape are in surface contact, thus guaranteeing that the second plane of the SMA faces the direction suitable for automated placement, the automatic placement machine can determine the position of the second plane through simple positioning and quickly complete the placement operation on the second plane. Therefore, during automated placement of the transformer, no case is required, and the partial embedding of the SMA within the frame, along with the surface contact between the first plane and the second adhesive tape, ensures that the flatness and parallelism of the second plane meet the requirements for automated placement, facilitating its smooth completion. Furthermore, compared to the transformer's maximum dimension B after adding a case, the transformer's maximum dimension A is significantly smaller than B, resulting in a smaller overall size and lower cost. This aligns with the industry's miniaturization and low-cost development philosophy. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view of an existing structure in the background art of this invention;

[0025] Figure 2 This is a schematic diagram of the structure of a transformer that facilitates automated patch mounting in Embodiment 1 of the present invention;

[0026] Figure 3 This is a cross-sectional view of the transformer structure that facilitates automated patch mounting in Embodiment 1 of the present invention;

[0027] Figure 4 This is a schematic diagram of the surface mount assembly of a transformer that facilitates automated surface mount assembly in Embodiment 1 of the present invention;

[0028] Figure 5 This is a schematic diagram of the structure of a transformer that facilitates automated patch mounting in Embodiment 2 of the present invention.

[0029] In the picture:

[0030] 1. Magnetic core; 11. First tape; 2. Frame; 21. Pin; 22. Insertion slot; 23. Mounting slot; 3. Surface mount assembly; 31. Second plane; 32. Surface mount board; 33. Limiting part; 34. Insertion part; 4. Coil; 41. Second tape; 10. Case. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0032] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0034] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0035] As a core component in the field of power electronics, the EE type wound transformer suffers from severe magnetic leakage and high energy loss due to its open magnetic circuit, making it difficult to meet the requirements of high-frequency and miniaturized equipment. The EE type core, through a combination of two "E"-shaped cores and an "I"-shaped core, forms a closed magnetic circuit structure, increasing magnetic flux density utilization by over 40% while controlling magnetic leakage to within 1 / 5 of that of traditional structures. Its separate frame and core design not only optimizes heat dissipation but also reduces copper losses by shortening the coil length. Combined with low-loss silicon steel sheets, this extends the operating frequency range to 50kHz-1MHz.

[0036] Based on the aforementioned advantages, EE-type wound transformers have a wide range of applications. For example, in industrial control, their ±0.1% voltage accuracy ensures precise motion control for robotic arms and CNC machine tools. In the new energy industry, photovoltaic inverters use this transformer to achieve efficient DC-AC conversion, with system efficiency exceeding 98%. The consumer electronics market has spurred the development of 12mm×8mm×5mm miniature patch products, supporting the stable operation of 5G base station power modules in extreme environments ranging from -40℃ to +125℃. In the medical equipment field, its crucial role is even more evident; MRI magnetic resonance imaging systems, through customized EE-type transformers, compress the power ripple coefficient to below 0.01%, directly improving imaging resolution and diagnostic accuracy.

[0037] The EE-type transformer is precisely integrated from five major modules: the magnetic core system, winding assembly, insulation system, pin terminations, and packaging shell. The magnetic core utilizes a cold-rolled, grain-oriented silicon steel sheet lamination process, with a nano-level insulating coating to reduce eddy current losses. The windings are achieved through multi-layer close winding using an automated winding machine, with polyimide films inserted between layers to form a gradient insulation structure. The pin terminations are gold-plated to enhance conductivity and are reliably connected to the PCB board via wave soldering. This modular design enables the product to cover power ranges from 1W to 10kW, and precise current / voltage matching can be achieved by adjusting the air gap in the magnetic core.

[0038] In the production of EE-type transformers, the introduction of automated surface mount technology (SMT) equipment marks a crucial turning point for EE-type transformers, ushering in a new era of industrial manufacturing. Traditional manual SMT has a positioning deviation of 0.1mm, while vision-guided automated SMT machines can control the accuracy within ±0.02mm, ensuring perfect alignment between micro-components and pads. The process comprises three core steps: First, a high-precision feeder separates micro-components such as 0402 and 0201, using a vacuum nozzle to perform a 180° flip for material handling; then, driven by an XYZ three-axis linkage system, the components are precisely positioned above the pads at a speed of 0.1m / s; finally, hot air reflow soldering melts the lead-free solder, forming a reliable IMC intermetallic compound layer. The entire process is monitored in real time by the MES system, allowing traceability of the batch of each component, placement parameters, and testing data, increasing the first-pass yield from 85% to 99.2%, fully meeting the stringent reliability requirements of fields such as new energy vehicles and aerospace.

[0039] Automated surface mount technology (SMT) allows EE-type transformers to integrate more functional modules, such as EMI filter circuits and temperature sensors, directly encapsulated on the core surface to form highly integrated power modules. Industry data shows that companies using intelligent mounting lines achieve three times the power density of their products and 40% shorter development cycles compared to traditional processes. This technological iteration is continuously driving the evolution of power electronic devices towards greater efficiency and compactness. Therefore, to better adapt to automated SMT technology, a corresponding Case 10 is installed on the transformer. The interior of Case 10 covers the entire transformer frame, while the outer top wall of Case 10 is flat to accommodate automated SMT equipment. However, the inclusion of Case 10 significantly increases the overall size of the transformer, and the manufacturing and installation processes of Case 10 require additional costs, creating a conflict with the industry's development philosophy of miniaturization and low cost.

[0040] This invention discloses a transformer (hereinafter referred to as "the transformer") that facilitates automated surface mount technology (SMT) placement. This transformer is adaptable to automated SMT placement equipment while further reducing its overall size. Specifically, the transformer of this invention eliminates the need for Case 10, instead using a flat plate structure on top to form a plane. This plane is compatible with automated SMT placement processes. Furthermore, the elimination of Case 10 significantly reduces the overall size of the transformer, thereby reducing its volume and manufacturing cost.

[0041] Example 1:

[0042] Reference Figures 2 to 4 , Figure 2 This is a schematic diagram of the structure of a transformer that facilitates automated patch mounting in Embodiment 1 of the present invention; Figure 3This is a cross-sectional view of the transformer structure that facilitates automated patch mounting in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the surface mount assembly of a transformer for automated surface mount assembly according to Embodiment 1 of the present invention. The transformer includes a magnetic core 1, a frame 2, a coil 4, and a surface mount assembly 3. The magnetic core 1 has a first adhesive tape 11 on its exterior; the frame 2 passes through the magnetic core 1; the coil 4 is sleeved on the frame 2, and the coil 4 has a second adhesive tape 41 on its exterior; the surface mount assembly 3 has a first plane and a second plane 31 facing away from each other, and the surface mount assembly 3 is inserted into and at least partially embedded in the frame 2 so that the first plane is in contact with the second adhesive tape 41, and the second plane 31 is used for automated surface mount assembly.

[0043] Specifically, the magnetic core 1 is block-shaped, and a first adhesive tape 11 is wrapped around its exterior. The first adhesive tape 11 is a special tape for the magnetic core 1, which can provide interlayer insulation and vibration resistance. The interior of the magnetic core 1 is hollow, and the frame 2 is inserted inside the magnetic core 1, making the transformer have a flat overall design, which can support reflow soldering and facilitate automated surface mount technology. The coil 4 is wound in the middle of the frame 2. The coil 4 can be made of single-strand, multi-strand copper wire, flat wire, etc., or other types of wire can be rotated as needed. The second adhesive tape 41 is wound around the outer periphery of the coil 4 to prevent the coil 4 from short-circuiting.

[0044] The frame 2 also features pins 21, with three pins 21 on each side to form a six-pin 21 design. This six-pin 21 design provides the transformer with more flexible winding configuration space. Traditional two-pin structures can only support a single primary-secondary winding connection, while the six-pin 21 design, through combination, can achieve multi-winding outputs or complex circuit topologies. For example, in a flyback switching power supply, the pins 21 on both sides can be connected to the primary winding, the secondary main output winding, and the auxiliary power supply winding, respectively. Independent pins 21 achieve voltage isolation and energy distribution, avoiding mutual interference between windings. Simultaneously, some pins 21 can be designed as floating terminals for connecting feedback circuits or overvoltage protection components, improving the stability and safety of the power supply system.

[0045] When the EE-type magnetic core is fitted onto the outside of the frame 2, the pins 21 on both sides are soldered onto the PCB board to form fixed support points. Combined with the retaining wall design at the bottom of the frame 2, this effectively resists vibration and impact during operation. The pin spacing 21 typically follows IPC standards (e.g., 2.54mm or 2.0mm) to ensure precise alignment with the PCB pads, preventing core misalignment or frame deformation due to stress concentration during soldering. Furthermore, the pin length and diameter are optimized to provide sufficient mechanical strength while controlling heat input during soldering, avoiding damage to the insulation material of the frame 2 from high temperatures. In high-frequency applications, the transformer needs to transmit energy and control signals simultaneously; the grouped layout of the pins 21 allows for physical isolation. For example, the three primary-side pins 21 can be concentrated on one side, and the three secondary-side pins 21 distributed on the other side, separating the high-voltage and low-voltage areas through PCB routing, reducing common-mode interference. Some designs also embed shielding layers between the pins 21 or use differential traces to further suppress electromagnetic radiation. This isolation design is particularly important in medical devices (such as MRI power supplies) or communication base stations (such as 5G micro base stations) to ensure signal integrity meets stringent EMC standards.

[0046] The patch assembly 3 is located on the top wall of the frame 2, and its bottom wall serves as a first plane. The first plane can be embedded inside the frame 2 and press against the top of the second adhesive tape 41, forming a surface fit. The top wall of the patch assembly 3 serves as a second plane 31, which can be adapted to an automated patch machine to achieve automated patching.

[0047] By inserting the patch assembly 3 onto the transformer, and ensuring that the patch assembly 3 is at least partially embedded in the frame 2, while simultaneously ensuring that the first plane and the second adhesive tape 41 are in surface contact, thus guaranteeing that the second plane 31 of the patch assembly 3 faces the direction suitable for automated patching, the automatic patching machine can determine the position of the second plane 31 through simple positioning and then quickly complete the patching operation on the second plane 31. Therefore, when the transformer is automatically patched, there is no need to set Case 10 (refer to...). Figure 1 Furthermore, the patch assembly 3 is embedded within the frame 2, allowing the first plane to form a surface fit with the second adhesive tape 41. This ensures that the flatness and parallelism of the second plane 31 meet the requirements for automated patching, facilitating the smooth completion of automated patching. Additionally, compared to the highest transformer size B after adding Case 10 (refer to...),... Figure 1 The transformer's highest dimension A is significantly smaller than its highest dimension B, resulting in a smaller overall size and lower cost. This makes the improvement of the transformer consistent with the industry's development philosophy of miniaturization and low cost.

[0048] Reference Figure 4Optionally, the patch assembly 3 includes a patch plate 32 and a limiting part 33. The patch plate 32 is positioned above the frame 2 and has a first plane and a second plane 31; the limiting part 33 is disposed on the patch plate 32 and is inserted into the frame 2.

[0049] Specifically, the patch plate 32 is flat, and its horizontal projection can be rectangular or other polygonal, or circular, elliptical, or other annular shapes. The upper and lower sides of the patch plate 32 are both planes, serving as the first plane and the second plane 31, respectively. A limiting part 33 extending vertically is provided at the edge of the patch plate 32. The patch plate 32 and the limiting part 33 are integrally structured to ensure high connection strength. In other embodiments, the limiting part 33 can also be connected to the patch plate 32 by welding, bonding, snap-fitting, or plugging.

[0050] The limiting part 33 can be inserted into the frame 2 to form a fixed connection between the patch plate 32 and the frame 2. The limiting part 33 can be block-shaped, plate-shaped, or other shapes. In this embodiment, multiple limiting parts 33 are arranged at intervals to ensure a high connection strength between the patch plate 32 and the frame 2, which can meet the requirements of automatic patching.

[0051] Optionally, the limiting part 33 is plate-shaped, and a limiting part 33 is provided on both sides of the patch plate 32.

[0052] Specifically, a plate-shaped limiting part 33 is provided on both sides of the patch plate 32, and the limiting part 33 extends along the length direction of the patch plate 32, so that the limiting part 33 and the patch plate 32 form a patch assembly 3 with a U-shaped cross section, and the opposite sides of the two limiting parts 33 can be pressed against the second adhesive tape 41. In this way, both sides of the patch plate 32 can be inserted into the frame 2 through the limiting part 33, so that the patch plate 32 can be stably fixed on the upper side of the frame 2.

[0053] Optionally, at least one end of the limiting part 33 protrudes from the patch plate 32 and forms a plug-in part 34, and the frame 2 has a plug-in groove 22 that engages with the plug-in part 34.

[0054] Specifically, the length of the limiting part 33 is greater than the length of the patch plate 32, so that at least one end of the limiting part 33 protrudes from the patch plate 32 to form an insertion part 34. An insertion groove 22 is opened at the corresponding part of the skeleton 2, and the insertion part 34 is inserted into the insertion groove 22. In this embodiment, the insertion part 34 is also plate-shaped, and the thickness of the insertion part 34 is equal to the width of the insertion groove 22, so that the side of the insertion part 34 and the groove wall of the insertion groove 22 form a surface fit, so as to further improve the limiting effect on the patch plate 32 and ensure that the parallelism of the second plane 31 meets the patching requirements.

[0055] Optionally, the top of the frame 2 has a mounting slot 23 for mounting the patch plate 32.

[0056] Specifically, the middle of the frame 2 is recessed to form a space for the coil 4 to be wound. A mounting groove 23 is formed on the top wall of the frame 2. The mounting groove 23 is located in the middle of the frame 2, and its length is equal to the length of the patch plate 32, so that when the patch plate 32 is placed in the mounting groove 23, both sides of the patch plate 32 can form a surface fit with the groove wall of the mounting groove 23. The depth of the mounting groove 23 is greater than or equal to the thickness of the patch plate 32, so that the top wall of the patch plate 32 is lower than or flush with the top wall of the frame 2. In this embodiment, the thickness of the patch plate 32 is 0.1 mm, which is less than the depth of the mounting groove 23, so that the top wall of the patch plate 32 is lower than the top wall of the frame 2, so that the maximum height of the frame 2 is the maximum height of the transformer.

[0057] Example 2:

[0058] Based on Embodiment 1, the difference between this embodiment and Embodiment 1 lies in the different composition of the patch assembly.

[0059] Reference Figure 5 , Figure 5 This is a schematic diagram of the transformer structure for automated patch mounting according to Embodiment 2 of the present invention. Optionally, the patch assembly 3 includes only a patch plate 32. A mounting groove 23 is formed on the top wall of the frame 2. A limiting groove is formed by recessing the side wall of the mounting groove 23. The side of the patch plate 32 is inserted into the limiting groove, and the side of the patch plate 32 is tightly abutted against the side wall of the limiting groove. By only providing the patch plate 32, the complexity of the structure can be further reduced, thereby reducing the processing difficulty and manufacturing cost.

[0060] Optionally, to further improve positioning accuracy, insertion slots (not shown in the figure) can be further opened on the groove wall of the limiting groove, and multiple plate-shaped insertion parts (not shown in the figure) can be welded on the side of the patch plate 32. Each insertion part is inserted into the corresponding limiting groove, and the side of the insertion part is in surface contact with the groove wall of the insertion slot to improve positioning and support effects.

[0061] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A transformer that facilitates automated surface mount technology (SMT) assembly, characterized in that, include: A magnetic core (1) having a first adhesive tape (11) on its exterior; The skeleton (2) is inserted inside the magnetic core (1); A coil (4) is fitted onto the frame (2), and the outside of the coil (4) has a second adhesive tape (41); The patch assembly (3) has a first plane and a second plane (31) facing away from each other. The patch assembly (3) is inserted into the skeleton (2) and is at least partially embedded in the skeleton (2) such that the first plane is in contact with the second tape (41) surface, and the second plane (31) is used for automated patching.

2. The transformer for automated patch mounting according to claim 1, characterized in that, The patch assembly (3) includes: The patch plate (32) is placed above the skeleton (2) and has the first plane and the second plane (31).

3. The transformer for automated surface mount assembly according to claim 2, characterized in that, The patch assembly (3) also includes: The limiting part (33) is disposed on the patch plate (32) and is inserted into the skeleton (2).

4. The transformer for automated surface mount assembly according to claim 3, characterized in that, The limiting part (33) is provided in multiple intervals; and / or, The limiting part (33) is plate-shaped, and one limiting part (33) is provided on each side of the patch plate (32).

5. The transformer for automated surface mount assembly according to claim 3, characterized in that, The limiting part (33) protrudes from the patch plate (32) at least one end and forms a plug-in part (34), and the skeleton (2) has a plug-in groove (22) that engages with the plug-in part (34).

6. The transformer for automated surface mount technology according to claim 5, characterized in that, The side of the plug portion (34) is in contact with the side wall of the plug groove (22).

7. The transformer for automated surface mount assembly according to claim 2, characterized in that, The top of the frame (2) has a mounting groove (23) for mounting the patch plate (32).

8. The transformer for automated surface mount assembly according to claim 7, characterized in that, The side of the patch plate (32) is in surface contact with the groove wall of the mounting groove (23).

9. The transformer facilitating automated patch mounting according to any one of claims 2 to 8, characterized in that, The top wall of the patch plate (32) is lower than or flush with the top wall of the skeleton (2).

10. The transformer facilitating automated patch mounting according to any one of claims 2 to 8, characterized in that, The patch plate (32) and the limiting part (33) are integrated into one piece.

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