Isolation transformer

Abstract

The application provides an isolation transformer, which comprises a magnetic core, a primary coil, a secondary coil, an isolation rubber paper and a magnetic cover. The primary coil and the secondary coil are coaxially arranged on the magnetic core; the isolation rubber paper is wrapped on the outer surfaces of the primary coil and the secondary coil. The magnetic cover is sleeved on the magnetic core to jointly enclose a certain accommodating space with the magnetic core, and the primary coil, the secondary coil and the isolation rubber paper are all completely accommodated in the space, so that the space utilization and the structural compactness are improved. In order to enhance the sealing property and the mechanical strength of the whole structure, a solidifiable epoxy resin encapsulating glue is arranged at the joint part of the magnetic cover and the magnetic core, and the encapsulating glue forms a continuous and seamless sealing layer after solidification, so that the invasion of external moisture and corrosive medium is effectively blocked, and the salt spray corrosion resistance is good. As the magnetic shielding structure of the isolation transformer, the magnetic cover not only significantly reduces the leakage magnetic flux, but also improves the overall mechanical stability through the rigid shell structure.

Description

Technical Field

[0001] This application belongs to the field of isolation transformer technology, and more specifically, relates to an isolation transformer and its manufacturing method. Background Technology

[0002] Traditional transformers generally employ a split structure, with components such as the core, windings, insulation, and casing assembled via mechanical connections. This construction results in numerous assembly gaps and moving parts within the equipment. During long-term operation, mechanical vibration can easily cause internal structural displacement, leading to potential faults such as winding deformation and insulation degradation. Furthermore, existing transformers have structural weaknesses at their joints, resulting in insufficient sealing performance and mechanical strength. Utility Model Content

[0003] The purpose of this application is to provide an isolation transformer and its manufacturing method to solve the technical problems of insufficient compactness and inadequate sealing of transformers in the prior art.

[0004] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0005] An isolation transformer is provided, comprising a magnetic core, a primary coil, a secondary coil, insulating tape, and a magnetic cover; the primary coil and the secondary coil are both wound on the magnetic core; the insulating tape covers the outside of the primary coil and the secondary coil; the magnetic cover is fitted onto the magnetic core, and the primary coil, the secondary coil, and the insulating tape are located within an accommodating space formed by the magnetic cover and the magnetic core; a curable encapsulating adhesive is also provided at the joint between the magnetic cover and the magnetic core to encapsulate the primary coil, the secondary coil, and the insulating tape within the accommodating space.

[0006] As a further improvement to the above technical solution:

[0007] Optionally, the magnetic cover has multiple end electrodes integrated on it, each of which is spaced apart from each other and electrically connected to the corresponding primary coil and secondary coil.

[0008] Optionally, the magnetic core includes a core portion and end plates located at both ends of the core portion, wherein the diameter of the end plates is larger than the size of the core portion.

[0009] Optionally, the edge of the end plate is provided with multiple notches, through which the lead wires of the primary coil or secondary coil pass through the end plate to be electrically connected to the end electrode.

[0010] Optionally, all of the terminal electrodes are disposed on the same surface of the magnetic cover, and the terminal electrodes include a primary coil input electrode, a primary coil output electrode, a secondary coil input electrode, and a secondary coil output electrode.

[0011] Optionally, the terminal electrode includes a lead / tin outer layer, a nickel middle layer, and a silver base layer stacked sequentially, wherein the silver base layer is attached to the substrate of the magnetic shield.

[0012] Optionally, the primary coil and the secondary coil are a two-wire parallel winding structure.

[0013] This application also provides a method for manufacturing an isolation transformer, comprising the following steps:

[0014] The primary and secondary coils are wound together on the magnetic core using a double-wire parallel winding structure;

[0015] Insulating tape is wrapped around the outside of the primary and secondary coils;

[0016] Install the magnetic core, which has been wound with the primary coil, secondary coil, and insulating tape, inside the magnetic cover; and lead the leads on the primary coil and secondary coil out of the magnetic core through the notch on the magnetic core respectively;

[0017] Curable encapsulating adhesive is filled into the joint between the magnetic cover and the magnetic core to encapsulate the primary coil, secondary coil, and insulating tape within the accommodating space formed by the magnetic cover and the magnetic core; and the encapsulating adhesive is cured by heating.

[0018] The leads of the primary coil and the secondary coil are respectively soldered to the corresponding end electrodes of the magnetic shield.

[0019] The advantages of the isolation transformer and manufacturing method provided in this application are as follows:

[0020] The isolation transformer of this application includes a magnetic core, a primary coil, a secondary coil, insulating tape, and a magnetic cover. The magnetic core uses a soft magnetic ferrite core as its base material. The primary and secondary coils are tightly wound coaxially around the magnetic core, forming an electromagnetic coupling structure. The insulating tape is made of high-temperature resistant insulating tape, completely covering the outer surfaces of the primary and secondary coils. The magnetic cover is made of soft magnetic ferrite nickel-zinc material, forming a cover structure that matches the magnetic core. After being fitted onto the magnetic core, it together with the magnetic core encloses a certain accommodating space, completely accommodating the primary coil, secondary coil, and insulating tape, thereby improving space utilization and structural compactness. To enhance the overall sealing and mechanical strength, a curable epoxy resin encapsulant is provided at the joint between the magnetic cover and the magnetic core. After curing, this encapsulant forms a continuous, seamless sealing layer, effectively blocking the intrusion of external moisture and corrosive media, and exhibiting good resistance to salt spray corrosion. As the magnetic shielding structure of the isolation transformer, the magnetic cover not only significantly reduces leakage flux but also improves overall mechanical stability through its rigid shell structure. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a top view of the isolation transformer provided in this application.

[0023] Figure 2 This is a cross-sectional structural schematic diagram of the isolation transformer provided in this application;

[0024] Figure 3 A bottom view of the isolation transformer provided in this application;

[0025] Figure 4 This is a side view of the isolation transformer provided in this application.

[0026] Figure 5 A top view of the magnetic core of the isolation transformer provided in this application;

[0027] Figure 6 A schematic diagram of the main structure of the magnetic core of the isolation transformer provided in this application;

[0028] Figure 7 A top view of the magnetic shield of the isolation transformer provided in this application;

[0029] Figure 8 This is a bottom view of the magnetic shield of the isolation transformer provided in this application.

[0030] The following are the labeling elements in the figure:

[0031] 1. Magnetic core; 11. Core section;

[0032] 12. End plate section; 121. Notch;

[0033] 2. Primary coil; 3. Secondary coil;

[0034] 4. Release tape; 5. Magnetic shield;

[0035] 51. Primary coil input electrode; 52. Primary coil output electrode;

[0036] 53. Secondary coil input electrode; 54. Secondary coil output electrode. Detailed Implementation

[0037] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0038] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0041] 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 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 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.

[0042] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of this utility model.

[0043] In the following description, suffixes such as "module," "part," "component," or "unit" are used only for the purpose of describing this utility model and have no specific meaning in themselves. Therefore, they can be used in combination.

[0044] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0045] To address the technical problems of existing transformers, such as loose structure, insufficient sealing, and poor vibration and impact resistance, Figures 1 to 4 As shown, this application provides an isolation transformer, including a magnetic core 1, a primary coil 2, a secondary coil 3, an insulating tape 4, and a magnetic cover 5.

[0046] The magnetic core 1 uses a soft ferrite core as its base material. The primary coil 2 and the secondary coil 3 are tightly wound coaxially on the magnetic core 1 to form an electromagnetic coupling structure. The insulating paper 4 is made of high-temperature resistant insulating paper and completely covers the outer surfaces of the primary coil 2 and the secondary coil 3. The magnetic cover 5 is made of soft ferrite nickel-zinc material and forms a cover structure that matches the magnetic core 1. After being fitted onto the magnetic core 1, it together with the magnetic core 1 encloses a certain accommodating space. The primary coil 2, the secondary coil 3, and the insulating paper 4 are all completely accommodated within this space to improve space utilization and structural compactness.

[0047] To enhance the overall sealing and mechanical strength of the structure, a curable epoxy resin encapsulant is applied to the joint between the magnetic cover 5 and the magnetic core 1. After curing, this encapsulant forms a continuous, seamless sealing layer, effectively blocking the intrusion of external moisture and corrosive media, and exhibiting good resistance to salt spray corrosion. As the magnetic shielding structure of the isolation transformer, the magnetic cover 5 not only significantly reduces leakage flux but also improves overall mechanical stability through its rigid shell structure.

[0048] In one specific embodiment of this application, the magnetic shield 5 is manufactured using an integrated molding process, and its outer surface is integrated with multiple terminal electrodes spaced apart from each other. These terminal electrodes form an integral structure with the magnetic shield 5, ensuring the reliability of the mechanical connection. Each terminal electrode is electrically connected to the lead-out terminals of the corresponding primary coil 2 and secondary coil 3. The outer surface of the terminal electrodes is flush with the outer surface of the magnetic shield 5, which not only helps to reduce the overall size of the transformer but also facilitates surface mounting on the circuit board. At the same time, the integrated structure of the terminal electrodes and the magnetic shield 5 avoids the risk of poor contact caused by vibration at the connection points, improving the long-term stability of the electrical connection.

[0049] like Figure 5 and Figure 6 As shown in a specific embodiment of this application, the magnetic core 1 includes a core portion 11 and end plate portions 12 located at both ends of the core portion 11. The core portion 11 is an elongated columnar structure, with end plate portions 12 at both axial ends. The end plate portions 12 are disc-shaped or rectangular plate-shaped structures, with their radial dimensions larger than the cross-sectional dimensions of the core portion 11, forming protruding edge structures. The end plate portions 12 provide a more stable support foundation for the winding of the primary coil 2 and the secondary coil 3, while also helping to improve magnetic flux distribution and reduce magnetic circuit losses.

[0050] like Figure 5 and Figure 6 As shown, in one specific embodiment of this application, the edge of the end plate portion 12 has multiple notches 121, the size of which matches the diameter of the lead wires of the primary coil 2 and the secondary coil 3. After the lead wires of the primary coil 2 and the secondary coil 3 extend along the axial direction of the magnetic core 1, they pass through the corresponding notches 121 and exit the end plate portion 12, achieving electrical connection with the end electrodes integrated on the magnetic cover 5. The inner wall of the notch 121 has a smoothly transitioning arc-shaped structure to avoid mechanical damage to the wires during the insertion process. The notches 121 not only ensure the structural integrity of the end plate portion 12, but also provide reliable positioning and fixing functions for the lead wires, ensuring that the wires will not shift or loosen under vibration.

[0051] like Figure 7 and Figure 8 As shown, in one specific embodiment of this application, four independent end electrodes are integrated and arranged on the same mounting plane of the magnetic cover 5, including a primary coil input electrode 51, a primary coil output electrode 52, a secondary coil input electrode 53, and a secondary coil output electrode 54. Each end electrode forms an integrated structure with the magnetic cover 5 and is arranged at a predetermined interval to ensure sufficient electrical clearance between adjacent electrodes. The primary coil input electrode 51 and the primary coil output electrode 52 are respectively connected to the start and end ends of the primary coil 2, while the secondary coil input electrode 53 and the secondary coil output electrode 54 are correspondingly connected to the start and end ends of the secondary coil 3.

[0052] In one specific embodiment of this application, the end electrode adopts a multilayer composite metal structure, consisting of a silver base layer, a nickel intermediate layer, and a lead / tin outer layer from the inside out. The silver base layer uses silver paste material with a silver content of 70%, which is metallurgically bonded to the substrate of the magnetic cover 5 through a high-temperature sintering process. The sintering temperature is controlled within the range of 850-900℃ to ensure a dense bonding interface between the silver base layer and the substrate, with a plating thickness of 8μm. The nickel intermediate layer is deposited on the surface of the silver base layer through an electroplating process, with a thickness of 6μm, serving as a barrier layer to effectively inhibit the diffusion of tin atoms from the solder into the silver layer during high-temperature soldering. The lead / tin outer layer uses eutectic solder composition and is formed into a 10μm thick protective layer through a hot-dip plating process. This outer layer provides good oxidation protection for the end electrode while ensuring soldering performance. Through the synergistic effect of each metal layer, the end electrode maintains excellent conductivity while possessing good mechanical strength and heat resistance.

[0053] In one specific embodiment of this application, the primary coil 2 and the secondary coil 3 are simultaneously wound on the core portion 11 of the magnetic core 1 using a double-wire parallel winding process. This winding method ensures that the primary coil 2 and the secondary coil 3 maintain a symmetrical spatial distribution, guaranteeing optimal electromagnetic coupling between the two windings. During the double-wire parallel winding process, the two insulated wires maintain a constant spacing and parallelism, effectively reducing the distributed capacitance between the windings.

[0054] This application also provides a method for manufacturing an isolation transformer. The method first involves simultaneously winding the primary coil 2 and the secondary coil 3 onto the core portion 11 of the magnetic core 1 using a double-wire parallel winding process, ensuring that the two windings are symmetrically distributed. After winding, insulating adhesive paper 4 is uniformly wrapped around the outer surfaces of the primary coil 2 and the secondary coil 3 to form a complete insulating protective layer. Then, the assembled magnetic core assembly is installed inside the magnetic cover 5, allowing the leads of the primary coil 2 and the secondary coil 3 to extend outwards through a pre-set notch 121 on the end plate portion 12. Epoxy resin encapsulant is injected at the joint between the magnetic cover 5 and the magnetic core 1, ensuring that the encapsulant completely fills all gaps. The assembled transformer is placed in a curing oven and cured at 120-150℃ for 2-4 hours, allowing the encapsulant to form a dense, sealed structure. Finally, the leads of the primary coil 2 and the secondary coil 3 are reliably connected to the primary coil input electrode 51, the primary coil output electrode 52, the secondary coil input electrode 53, and the secondary coil output electrode 54 on the magnetic cover 5, respectively, to complete the overall assembly of the transformer.

[0055] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An isolation transformer, characterized in that, The device includes a magnetic core (1), a primary coil (2), a secondary coil (3), a release liner (4), and a magnetic shield (5). The primary coil (2) and the secondary coil (3) are both wound around the magnetic core (1). The release liner (4) covers the outside of the primary coil (2) and the secondary coil (3). The magnetic shield (5) is fitted onto the magnetic core (1). The primary coil (2), the secondary coil (3), and the release liner (4) are located within the accommodating space formed by the magnetic shield (5) and the magnetic core (1). A curable encapsulating adhesive is also provided at the joint between the magnetic shield (5) and the magnetic core (1) to encapsulate the primary coil (2), the secondary coil (3), and the release liner (4) within the accommodating space.

2. The isolation transformer as described in claim 1, characterized in that, The magnetic shield (5) has multiple end electrodes integrated on it. Each end electrode is arranged at intervals and is electrically connected to the corresponding primary coil (2) and secondary coil (3).

3. The isolation transformer as described in claim 2, characterized in that, The magnetic core (1) includes a core portion (11) and end plate portions (12) located at both ends of the core portion (11), wherein the diameter of the end plate portion (12) is larger than the size of the core portion (11).

4. The isolation transformer as described in claim 3, characterized in that, The edge of the end plate (12) is provided with a plurality of notches (121), through which the lead wires of the primary coil (2) or the secondary coil (3) pass through the end plate (12) to be electrically connected to the end electrode.

5. The isolation transformer as described in claim 2, characterized in that, All of the terminal electrodes are located on the same surface of the magnetic cover (5). The terminal electrodes include a primary coil input electrode (51), a primary coil output electrode (52), a secondary coil input electrode (53), and a secondary coil output electrode (54).

6. The isolation transformer as described in claim 2, characterized in that, The terminal electrode comprises a lead / tin outer layer, a nickel middle layer and a silver base layer stacked sequentially, wherein the silver base layer is attached to the substrate of the magnetic shield (5).

7. The isolation transformer as described in claim 1, characterized in that, The primary coil (2) and the secondary coil (3) are a double-wire parallel winding structure.

Images