Low-frequency transformer with strengthened pin structure

Abstract

The utility model particularly relates to a low-frequency transformer with a strengthened pin structure, which comprises a framework body and a pin, one end of the pin is a T-shaped pin, the diameter of the T-shaped pin is smaller than that of a pin main body, the T-shaped pin is completely embedded into an injection molding cavity of the framework body, and the pin and the framework body are integrally formed through injection molding. According to the structure, the pins and the framework body are integrally formed through injection molding, the manual pre-embedding step is omitted, the structure is suitable for automatic production, and the production efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to transformer manufacturing technical field, concretely is a kind of low-frequency transformer with reinforced pin structure, which is structurally stable and has high production efficiency. BACKGROUND

[0002] The pins of the traditional low-frequency transformer skeleton are designed with pre-embedded T-shaped pins. During production, the pins need to be fixed manually, which leads to complex processes, high costs and poor consistency. In the prior art, such as the terminal pin structure disclosed in patent CN 102005286 A, although the pins are formed by a mold, the joint between the pins and the skeleton body only relies on injection molding, and no auxiliary structures such as anti-slip patterns or clamping grooves are provided, which causes the pins to loosen easily when vibrating or expanding due to heat. In addition, the positioning accuracy of the pins during injection molding is insufficient (offset > 0.1 mm), which results in a finished product yield of less than 85%. Therefore, there is an urgent need for a low-frequency transformer with a reinforced pin structure that is structurally optimized, firmly connected and easy to mass-produce. SUMMARY

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the utility model is to provide a low-frequency transformer with a reinforced pin structure, in which the pins and the skeleton body are integrally formed, the connection strength is high, and automatic production is facilitated.

[0004] According to the low-frequency transformer with a reinforced pin structure of the utility model, the skeleton body is installed on the iron core, one end of the pin is a T-shaped pin, the diameter of the T-shaped pin is smaller than the diameter of the main body of the pin, and the T-shaped pin is completely embedded in the injection cavity of the skeleton body, and the pin and the skeleton body are integrally formed by injection molding.

[0005] Specifically further, the end of the T-shaped pin is provided with an anti-slip pattern.

[0006] Specifically further, the anti-slip pattern is an annular groove, or the anti-slip pattern is a protrusion.

[0007] Specifically further, the inner wall of the injection cavity is provided with a clamping groove matched with the shape of the T-shaped pin, and the depth of the clamping groove is 1 / 3 to 1 / 2 of the height of the T-shaped pin.

[0008] Specifically further, the material of the pin is annealed copper wire, and an anti-oxidation tin layer is plated on the surface of the pin.

[0009] Specifically further, a positioning column is arranged in the injection cavity of the skeleton body, and an annular groove is arranged on the bottom surface of the injection cavity.

[0010] Specifically further, the skeleton body is provided with a reinforcing rib, and one end of the reinforcing rib extends below the inlet end of the injection cavity.

[0011] Specifically further, the end surface of the T-shaped needle foot is circular arc-shaped.

[0012] Specifically further, the other end of the needle foot is provided with a guide inclined surface, and the inclination angle of the guide inclined surface is 30° to 45°.

[0013] The beneficial effects of the utility model are as follows.

[0014] I. The structure is embedded in the injection cavity through the T-shaped needle foot, and multiple fixations are realized through the anti-skid lines, clamping grooves and other structures, so that the loosening problem of the traditional embedded needle foot is avoided.

[0015] II. The structure is integrally injection molded to omit the manual embedding step, is suitable for automatic production, and is high in production efficiency. DRAWINGS

[0016] The above and / or additional aspects and advantages of the utility model will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the following drawings.

[0017] Figure 1 It is a three-dimensional structure schematic view of the utility model.

[0018] Figure 2 It is a top view structure view of the needle foot and the injection cavity.

[0019] Figure 3 It is Figure 2 A-A sectional view structure schematic view.

[0020] Figure 4 It is Figure 2 B-B sectional view structure schematic view.

[0021] Figure 5 It is Figure 4 The local enlarged structure schematic view of C of

[0022] Figure 6 It is Figure 5 Another embodiment structure schematic view of

[0023] Figure 7 It is a T-shaped needle foot structure schematic view.

[0024] Figure 8 It is Figure 3 The local enlarged structure schematic view of D of

[0025] Figure 9 It is Figure 8 Another embodiment structure schematic view of

[0026] The marking of the drawings is as follows: skeleton body 1, injection cavity 11, clamping groove 111, positioning column 12, annular groove 121, reinforcing rib 13, pin 2, T-shaped pin 21, anti-skid line 211, guide inclined surface 23, iron core 3. DETAILED DESCRIPTION

[0027] The embodiments of the present application are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0028] Reference is made below Figures 1 to 9 The low-frequency transformer with reinforced pin structure disclosed by the present application is described below, which comprises an iron core 3, a skeleton body 1 and a pin 2, the skeleton body 1 is installed on the iron core 3, one end of the pin 2 is a T-shaped pin 21, the diameter of the T-shaped pin 21 is smaller than the diameter of the pin 2, and the T-shaped pin 21 is completely embedded in the injection cavity 11 of the skeleton body 1, and the pin 2 and the skeleton body 1 are integrally formed by injection molding.

[0029] The pin 2 and the skeleton body 1 of the structure are integrally injection molded to omit the manual embedding step, suitable for automatic production, and improve the production efficiency. The tensile strength of the pin 2 is improved by 30%, and the tensile test is carried out according to the GB / T 228.1-2021 standard. In addition, the material of the skeleton body 1 is polybutylene terephthalate PBT, model Celanex 2300GV, temperature resistance-40℃ to 150℃; the surface plating layer of the pin 2 is tin-bismuth alloy Sn96Bi4, thickness 8-10μm. Alternatively, the skeleton body 1 is injection molded by polyether ether ketone PEEK, temperature resistance grade 200℃.

[0030] Further specifically, the end of the T-shaped pin 21 is provided with an anti-skid line 211. As shown in Figure 6 , the first embodiment of the anti-skid line 211: the anti-skid line 211 is selected as a protrusion, and the protrusion height is 0.05-0.15mm. As shown in Figure 7 , the second embodiment of the anti-skid line 211: the anti-skid line 211 is an annular groove; the width of the annular groove is 0.1-0.3mm, and the depth of the annular groove is 0.05-0.15mm. The structure realizes multiple fixation by embedding the T-shaped pin 21 into the injection cavity and through the anti-skid line, clamping groove and other structures, avoiding the loosening problem of traditional embedded pins. The first embodiment and the second embodiment are both preferred options, and one of them is selected according to the designer.

[0031] As shown in Figure 9As shown, specifically further, the inner wall of the injection cavity 11 is provided with a groove 111 that matches the shape of the T-shaped pin 21, and the depth of the groove 111 is 1 / 3 to 1 / 2 of the height of the T-shaped pin 21.

[0032] The skeleton body 1 is injection molded from high-temperature resistant engineering plastic. Its injection cavity 11 contains a slot 111 and a positioning post 12. The T-shaped pins 21 of the pins 2 are embedded in the injection cavity 11, extending outwards through the slot 111, and the anti-slip texture 211 engages with the slot 111. During production, annealed copper wire is cut, pressed into T-shaped pins, and then directly injection molded with the skeleton mold to form an integrated structure. One end of the positioning post 12 extends to the outer arc surface of the T-shaped pin 21 to limit the position of the T-shaped pin 21 and prevent displacement.

[0033] Specifically, the pin 2 is made of annealed copper wire with an anti-oxidation tin layer plated on its surface. The thickness of the anti-oxidation tin layer is 5-10 μm.

[0034] like Figure 8 As shown, the injection cavity 11 of the skeleton body 1 is provided with a positioning post 12, and the bottom surface of the injection cavity 11 is provided with an annular groove 121. The width of the annular groove 121 is 1.1-1.2 times the diameter of the needle, and the depth of the annular groove 121 is 0.5-1.0 mm. The positioning post 12 cooperates with the annular groove 121 to achieve axial positioning.

[0035] like Figure 1 As shown, specifically, the skeleton body 1 is provided with a reinforcing rib 13, one end of which extends to the lower part of the inlet end of the injection cavity 11, thereby improving the structural strength.

[0036] like Figure 7 As shown, specifically, the end face of the T-shaped pin 21 is arc-shaped, and its radius of curvature is consistent with the corner radius of the injection cavity 11. In this embodiment, the end face of the T-shaped pin 21 is designed to be arc-shaped.

[0037] like Figure 7 As shown, specifically, the other end of the pin 2 is provided with a guide slope 23, the inclination angle of which is 30° to 45°. This serves as a locking mechanism on a portion of the inner wall of the injection cavity 11. Figure 6 As shown, the inner wall of the injection cavity 11 is provided with a chamfered structure 112, which cooperates with the guide slope 23. A sealant with a width of 0.8 mm is provided between the chamfered structure 112 and the guide slope 23, and it withstands a 48-hour salt spray test without corrosion. Furthermore, a metallized fiber mesh is embedded in the outer layer of the skeleton body 1 during injection molding. The mesh density of the metallized fiber mesh is 200 meshes, forming a Faraday cage structure that attenuates high-frequency radiation interference to below 30 dB.

[0038] The annular groove 121 of the positioning pin 12 has a V-shaped cross section, a groove width of 1.1mm (to accommodate pins with a diameter of 1mm), and a groove depth of 0.8mm. During injection molding, the middle section of the pin 2 is embedded into the groove through elastic deformation with an interference fit of 0.05mm to ensure no axial displacement.

[0039] A nano-ceramic coating is added to the inner wall of the injection cavity 11 of the skeleton body 1. The nano-ceramic coating is made of alumina nanoparticles (Al2O3) and epoxy resin, and is applied using a plasma spraying process. The coating thickness is 50-100μm, and the dielectric strength is ≥30kV / mm. It forms a composite insulating layer with the engineering plastic, improving arc resistance and anti-aging performance while maintaining injection molding process compatibility. The plating thickness at the end of the T-type pin is 8-10μm, while the main body maintains 5-6μm, balancing conductivity and mechanical bonding strength. The anti-slip texture 211 of the T-type pin 21 is pre-aligned with the slot 111 to ensure that the axial offset during injection molding is <0.05mm.

[0040] A miniature phase change thermal storage unit is embedded at the bottom of the frame body 1. The thermal storage unit is encapsulated in a copper shell and filled with a paraffin-based phase change material with a melting point of 60-80℃. It is coupled to the middle section of pin 2 through a 2mm diameter copper thermal conductive post, with a thermal conductivity ≥200W / m·K, thus slowing down the abnormal temperature rise rate. An elastic snap-fit ​​structure is added to the bottom of the frame body 1, including a V-shaped stainless steel spring and a limiting boss. The thickness of the V-shaped stainless steel spring is 0.3mm, which enables screwless installation with the PCB board and improves the vibration resistance level to the IEC 60068-2-6 standard.

[0041] Three sets of orthogonal positioning reference surfaces are added to the outside of the injection cavity 11. The three sets of orthogonal positioning reference surfaces are located on the bottom surface, left side surface and front surface of the skeleton body 1. The flatness is ≤0.02mm and laser-engraved cross alignment marks are provided to support multi-angle gripping and positioning in automated production lines.

[0042] The design includes a pluggable analog load terminal (containing a nickel-chromium alloy resistor) that can be quickly connected to pin 2 for aging tests, supporting a 1000-cycle insertion / removal lifespan. A tungsten alloy tracer point with a diameter of 0.5 mm is set on the top of the positioning post 12. This tracer point is used by the X-ray imaging system to automatically detect the embedding depth of the T-type pin 21 with an accuracy of ±0.1 mm.

[0043] A replaceable pin adapter sleeve was developed. The adapter sleeve is made of phosphor bronze, and its inner wall is interference-fitted with T-type pin 21. The outer diameter is compatible with two industrial standard pitches: 2.54mm and 3.96mm. The bobbin body 1 is designed with a three-section threaded connection structure. The pitch between adjacent winding cavities can be adjusted by rotation, with a pitch range of 5-15mm to adapt to different power level requirements.

[0044] The skeleton body 1 is injection molded using a 70:30 ratio of polylactic acid (PLA) and glass fiber composite bio-based material, achieving biodegradability while maintaining a temperature resistance of 150℃. The surface plating of the pins 2 is replaced with a tin-bismuth alloy (Sn96Bi4), with a melting point of 138℃, reducing the welding temperature by 20% and complying with RoHS 3.0 directive requirements. This invention can be widely applied in the field of low-frequency transformer manufacturing, and is especially suitable for electronic devices requiring high-reliability connections, such as power adapters and chargers, offering significant economic benefits and market competitiveness.

[0045] The anti-slip texture consists of annular grooves, 0.2 mm wide and 0.1 mm deep, evenly distributed along the circumference of the T-shaped pin with a spacing of 0.5 mm. Tensile testing verified that this design increases tensile strength by 30%. When the groove depth is 1 / 3 of the T-shaped pin height, the torsional force is 50 N·m; when the depth is 1 / 2, the torsional force increases to 75 N·m, balancing fixing strength and injection filling efficiency.

[0046] The annular groove has a width of 1.1 times the pin diameter and a depth of 0.8 mm. During injection molding, the pins are embedded through elastic deformation to form an interference fit. In the gradient plating process, the plating thickness at the T-pin tip is 8-10 μm, and the thickness of the main body is 5-6 μm. The electroplating current density is 2 A / dm², and the time is 10 minutes.

[0047] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A low-frequency transformer with a reinforced pin structure, comprising an iron core (3), a frame body (1), and pins (2), wherein the frame body (1) is mounted on the iron core (3), characterized in that: One end of the pin (2) is a T-shaped pin (21). The diameter of the T-shaped pin (21) is smaller than the diameter of the pin body (22). The T-shaped pin (21) is completely embedded in the injection cavity (11) of the skeleton body (1). The pin (2) and the skeleton body (1) are integrally formed by injection molding.

2. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The end of the T-shaped pin (21) is provided with anti-slip texture (211).

3. A low-frequency transformer with a reinforced pin structure according to claim 2, characterized in that: The anti-slip texture (211) is either an annular groove or a raised surface.

4. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The inner wall of the injection cavity (11) is provided with a groove (111) that matches the shape of the T-shaped pin (21), and the depth of the groove (111) is 1 / 3 to 1 / 2 of the height of the T-shaped pin (21).

5. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The pin (2) is made of annealed copper wire with an anti-oxidation tin layer plated on its surface.

6. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The injection cavity (11) of the skeleton body (1) is provided with a positioning post (12), and the bottom surface of the injection cavity (11) is provided with an annular groove (121).

7. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The skeleton body (1) is provided with reinforcing ribs (13), one end of which extends to the bottom of the inlet end of the injection cavity (11).

8. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The end face of the T-type pin (21) is arc-shaped.

9. A low-frequency transformer with a reinforced pin structure according to claim 1, characterized in that: The other end of the pin (2) is provided with a guide slope (23), the inclination angle of which is 30° to 45°.

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