Hanging tool special for plating nickel and gold on transformer
The transformer-specific plating fixture with a rotating linkage and dual-claw grip design addresses non-uniform plating and efficiency issues, achieving uniform plating and reduced operational time for high-reliability transformers.
Patent Information
- Application Number
- CN202510574838.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-06
- Publication Date
- 2025-07-15
AI Technical Summary
The traditional electroplating hanger structure makes it difficult to meet the transformer manufacturing needs due to the plating quality, production efficiency and product yield. Especially in low-temperature co-fired ferrite transformers, there are problems of plating unevenness and low operating efficiency.
A special nickel-plated transformer nickel-gold hanger including a rotatable link and a special fixture was designed. The electric field distribution is adjusted through the rotatable link, and a split fixture is used to avoid contact with the front pads. Combined with the insulation shielding layer and the conductive optimization design, it ensures the uniformity of the plating and production efficiency.
The uniformity of the plating is improved by 50%, production efficiency is improved by 67%, cost is reduced, and the volatility of the plating thickness is reduced to ±7%, adapting to the electric field characteristics of different plating tanks and ensuring the high-precision plating process of the transformer.
Smart Images
Figure CN120311285A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of transformers, and particularly to a special fixture for nickel-gold plating of transformers. Background Art
[0002] Transformers are important fuse parts in high-reliability and high-integration electronic devices such as manned / cargo spacecraft and airborne electronic countermeasure systems, individual combat weapons, and various missiles. However, the current transformers often have a relatively large volume and mass. Low-temperature co-fired ferrite (LTCF) transformers have the advantages of ultra-high integration, strong anti-shock and vibration resistance, high power density, etc., and can be widely used in various civil and military high-reliability and high-integration fields.
[0003] Because the application environment requires welding leads, the silver pads of low-temperature co-fired ferrite (LTCF) transformers need to be electroplated with nickel and then gold to increase the solderability and solder resistance of the electrodes. Moreover, the gold plating layer has the advantages of stable chemical properties, good heat resistance, and small contact resistance, and is suitable for micro-assembly processes such as gold wire ball bonding, conductive adhesive bonding, or gold-tin alloy welding, and can be used as the outermost electrode.
[0004] The electroplating process is a key link in the surface treatment of transformers. Its core goal is to ensure no fixture marks on the front pads by uniformly plating metal layers such as nickel and gold, and to improve the conductivity, oxidation resistance, and welding reliability of transformers. However, due to its structure, traditional electroplating fixtures have many technical bottlenecks, making it difficult to meet the manufacturing requirements of transformers in terms of plating quality, production efficiency, and product yield. Summary of the Invention
[0005] The purpose of the present invention is to provide a special fixture for nickel-gold plating of transformers to solve the above problems.
[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A special fixture for nickel-gold plating of transformers, comprising a frame body, conductive hooks, rotatable connecting rods, and clamps. Among them, The frame body is composed of two transverse main rods and two longitudinal main rods. The conductive hooks are arranged on the transverse main rods. The rotatable connecting rods are longitudinally and equidistantly distributed along the transverse main rods. Each rotatable connecting rod is connected to the transverse main rod through a hinge mechanism to achieve 360-degree free rotation, and its pose is fixed by a locking nut. The clamps are installed on the rotatable connecting rods and adopt a split structure. The clamps include clamping arms, buffer layers, and conductive contacts. The buffer layers are arranged on the inner sides of the clamping arms, and the conductive contacts are arranged at the ends of the clamps.
[0007] Those skilled in the art can understand that the fixture of the present application is applicable to all similar transformers including LTCF transformers.
[0008] As a preferred technical solution, the main rod is made of stainless steel. It has both high strength and corrosion resistance, and its surface is coated with an insulating layer to avoid the deposition of plating on non-target areas.
[0009] As a preferred technical solution, the transverse main rod, longitudinal main rod, and rotatable connecting rod are made of stainless steel. They have both high strength and corrosion resistance, and their surfaces are coated with an insulating layer to avoid the deposition of plating on non-target areas.
[0010] As a preferred technical solution, the surface of the main rod is coated with an insulating shielding layer.
[0011] As a preferred technical solution, the hook body of the conductive hook is U-shaped, the end of the conductive hook is provided with anti-slip lines, and the conductive hook is made of elastic copper alloy.
[0012] As a preferred technical solution, the clamping arm has a double-claw structure.
[0013] (1) As an important innovation point of the present application, a rotatable connecting rod is provided; Rotation adjustment mechanism: The connection between the connecting rod and the main rod adopts a rotating structure, which can rotate at different angles to adapt to the electric field distribution characteristics of different electroplating baths; (2) Special fixture design: Clamping arm structure: A double-claw design is adopted, and the inner wall of the claw part fits the non-pad area on the side of the transformer to avoid contacting the front pad. The clamping force is adjusted elastically by the fixture, which not only ensures the fixing stability but also prevents the generation of indentation marks; Buffer layer material: The inner side of the clamping claw is covered with a conductive silica gel layer (resistivity < 0.01 Ω·cm), which has both buffering and conductive functions to ensure uniform current distribution; (3) Conductive optimization design Multi-stage conduction path: The current is transmitted from the conductive hook through the main rod to the connecting rod, and then through the titanium alloy of the clamping arm to the conductive contact of the transformer, and the overall resistance is reduced to less than 0.05 Ω; Electric field shielding coating: The surface of the main rod is coated with an insulating shielding layer to reduce the edge electric field distortion and ensure the uniform migration of plating solution ions.
[0014] In summary, through the collaborative structure of the rotatable connecting rod, dynamic locking mechanism and special fixture, the present invention systematically solves the problems of plating uniformity, operation efficiency and compatibility of traditional fixtures, and provides a reliable technical solution for the high-precision transformer electroplating process.
[0015] Compared with the prior art, the advantages of the present invention are as follows: (1) The fixture indentation is completely eliminated. Through non-frontal contact clamping, there is no indentation in the front pad area of the transformer; (2) The plating layer uniformity is significantly improved. The dynamic adjustment of the rotatable link makes the plating thickness and the uniformity of the gold layer coverage increase by 50%; (3) The production efficiency is improved. The quick clamping design (5 seconds per piece) shortens the single-batch operation time by 67%; (4) Energy saving and cost advantages Only the contact points are plated with gold, and the cost is significantly reduced; (5) The insulating shielding layer reduces the interference of the migration of plating solution ions. Brief Description of the Drawings
[0016] Figure 1 is the overall front view of the hanger of the embodiment of the present invention; Figure 2 is the overall side view of the hanger of the embodiment of the present invention.
[0017] Figure 3 is Figure 1 the structural diagram of a single hanger in Figure 4 is the structural diagram of the fixture.
[0018] In the figure: 1, conductive rod; 2, horizontal main rod; 3, vertical main rod; 4, rotatable link; 5, rotating rod; 6, threaded rod; 7, fixture; 8, conductive hook; 9, conductive contact; 10, buffer layer; 11, clamping arm. Detailed Embodiment
[0019] The present invention will be further described below in conjunction with embodiments.
[0020] Embodiment 1:
[0021] Refer to Figures 1 to 3 , a special hanger for nickel-gold plating of transformers, including a conductive rod 1, a frame body, a rotatable link 4, a rotating rod 5, a threaded rod 6, a fixture 7 and a conductive hook 8, wherein, The conductive rod 1 is made of brass material and is mainly connected to the cathode of the electroplating tank to conduct electricity; The frame body is composed of two horizontal main rods 2 and two vertical main rods 3. The conductive hook 8 is arranged on the horizontal main rod 2; the rotatable links 4 are longitudinally equidistantly distributed along the horizontal main rod 2. Each rotatable link 4 is connected to the horizontal main rod 2 through a hinge mechanism to achieve 360-degree free rotation and is fixed in position by a locking nut; The two ends of the rotating rod 5 are respectively connected to the conductive rod 1 and the horizontal main rod 2. Its function is to connect the conductive rod 1 and the horizontal main rod 2 and can rotate, so that the whole hanger can rotate to change the angle; The threaded rod 6 is made of brass material and is used to connect the fixture 7. A 200-μm-thick epoxy resin insulating coating is sprayed to reduce the electroplated area of the hanger. Each threaded rod 6 can be rotated independently to change the angle The fixture 7 is installed on the rotatable link 4 and adopts a split structure. The fixture 7 includes a conductive contact 9, a buffer layer 10, and a clamping arm 11. As Figure 4 shown, the buffer layer 10 is arranged on the inner side of the clamping arm, the conductive contact is arranged at the end of the fixture, and the clamping arm is of a double-claw structure; In this embodiment, the materials of the transverse main rod 2, the longitudinal main rod 3, and the rotatable link 4 are all stainless steel; the surfaces of the transverse main rod 2 and the longitudinal main rod 3 are coated with an insulating shielding layer; The hook body of the conductive hook 8 is U-shaped, the end of the conductive hook 8 is provided with anti-slip lines, and the conductive hook 8 is made of elastic copper alloy.
[0022] This embodiment takes the LTCF transformer as an example: The process flow of nickel-gold plating for the LTCF transformer using the above-mentioned hanging tool is as follows: Hanging - Organic solvent degreasing - Chemical degreasing - Cathodic electrolytic degreasing - Pickling - Activation - Strike nickel - Activation - Electroplating nickel - Activation - Electroplating gold, specifically: (1) Hanging: Fix the workpiece on the hanging tool according to the requirements of the "Hanging Operation Instruction Manual", and the fixing method shall be strictly in accordance with the operation instruction manual; (2) Chemical degreasing: Immerse the hung workpiece in the heated solution; at the same time, turn on the ultrasonic wave, and then perform overflow double water washing, with the temperature being 70°C and the time being 10 min; (3) Activation: Place the workpiece processed in step (2) in the activation tank and completely immerse it in the activation solution, and then perform overflow double water washing; the activation formula is 50 g / L of activation acid salt, the activation temperature is room temperature, and the activation time is 45 s; (4) Electroplating dull nickel: Put the workpiece processed in step (3) into the electroplating dull nickel tank for electroplating dull nickel, and then perform overflow double water washing. The formula of the electroplating dull nickel solution is: Nickel sulfate: 320 g / L, Nickel chloride: 45 g / L, Boric acid: 45 g / L, Cathode current density: 1 A / dm 2 , Temperature: 55°C, pH 4.5; (5) Activation: Place the workpiece processed in step (4) in the activation tank and completely immerse it in the activation solution, and then perform overflow double water washing. The activation formula is in a 15 wt% dilute sulfuric acid solution, the activation temperature is room temperature, and the activation time is 45 s; (6) Pre-gold plating: Put the workpiece processed in step (5) into the pre-gold plating tank for pre-gold plating, and then perform overflow double water washing; the formula of the pre-gold plating solution is: Process conditions: Potassium aurocyanide: 1.9 g / L, pH 6.2, Specific gravity 1.16 g / cm³, Temperature 55°C, Cathode current density: 0.2 A / dm²; (7) Gold plating: Place the workpiece processed in step (6) into a gold plating bath for gold plating, and then perform overflow double water washing. The formula of the gold plating solution is: potassium gold cyanide 8.2 g / L, pH 6.2, specific gravity 1.16 g / cm³, temperature 55 °C, cathode current density 0.3 A / dm², gold plating additive; (8) Hot pure water washing: Place the workpiece processed in step (7) in hot pure water at 70 °C to wash the parts, and the washing time is 35 s; (9) Drying: Place the workpiece processed in step (8) into an oven for drying, and the temperature is 85 °C.
[0023] Effect comparison: Taking a certain model LTCF transformer as an example, compare the coating properties of nickel-gold plating using a traditional fixture and the fixture of the present invention: Coating uniformity: The thickness fluctuation range of the traditional fixture is 1.2 - 2.8 μm, and the present invention optimizes it to 1.5 - 2.1 μm (volatility ±15% → ±7%); Production efficiency: The single-batch loading and unloading time is shortened from 15 minutes to 5 minutes, and the production capacity is increased by 200%; It can be seen that: Through the collaborative design of the rotatable connecting rod, dynamic locking mechanism and special fixture, the present invention systematically solves the problems of coating uniformity, operation efficiency and compatibility of traditional fixtures, and provides a reliable technical solution for the electroplating process of high-precision transformers.
[0024] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A special fixture for nickel-gold plating of transformers, characterized in that, It includes a frame body, a conductive hook, a rotatable connecting rod and a clamp. Among them, the frame body is composed of two transverse main rods and two longitudinal main rods. The conductive hook is arranged on the transverse main rod. The rotatable connecting rods are longitudinally equidistantly distributed along the transverse main rod. Each rotatable connecting rod is connected to the transverse main rod through a hinge mechanism to achieve 360-degree free rotation and is fixed in position by a locking nut. The clamp is installed on the rotatable connecting rod and adopts a split structure. The clamp includes a clamping arm, a buffer layer and a conductive contact. The buffer layer is arranged on the inner side of the clamping arm, and the conductive contact is arranged at the end of the clamp.
2. The special fixture for nickel-gold plating of a transformer according to claim 1, wherein The transverse main rod, the longitudinal main rod and the rotatable connecting rod are made of stainless steel.
3. The special fixture for nickel-gold plating of a transformer according to claim 1, characterized in that, The surfaces of the transverse main rod and the longitudinal main rod are coated with an insulating shielding layer.
4. The dedicated hanger for nickel-gold plating of a transformer according to claim 1, characterized in that, The hook body of the conductive hook is U-shaped, and anti-slip patterns are provided at the end of the conductive hook. The conductive hook is made of elastic copper alloy.
5. The special fixture for nickel-gold plating of a transformer according to claim 1, characterized in that The clamping arm is of a double-claw structure.