Electroplating methods for cylindrical workpieces

Abstract

A method for electroplating a cylindrical workpiece involves mounting the cylindrical workpiece, open at both ends along its axial direction, onto a power supply fixture and immersing it in a circulating electroplating solution for electroplating. The workpiece is mounted onto the power supply fixture by inserting the fixture into the workpiece through one of its openings. The power supply fixture is constructed of a bent metal plate and includes: multiple elastic contact pieces that elastically contact the inner surface of the cylindrical workpiece to hold it in place and supply power to it; and a suppressing portion located inside the cylindrical workpiece to suppress the flow of the electroplating solution along its axial direction. The suppressing portion suppresses the flow of the electroplating solution inside the cylindrical workpiece while simultaneously electroplating it.

Description

Technical Field

[0001] This invention relates to an electroplating method for cylindrical workpieces. Background Technology

[0002] Figure 1A , Figure 1B , Figure 2 The structure and operation described in Patent Document 1 (Japanese Patent Application Publication No. 2001-335993) are examples of existing electroplating methods. Figure 1A , Figure 1B This indicates the state in which a workpiece is mounted on the impregnation retainer. Figure 2 This indicates the action of immersing the retaining element in a specified liquid bath.

[0003] In this example, the workpiece is a bag-shaped workpiece. Figure 1A , Figure 1B , Figure 2 The example shown is a bag-shaped nut 11. The impregnation retainer 12 includes: a long, elongated metal main body shaft 13 extending in the lifting direction; and multiple support rods 14 branching from the main body shaft 13 and obliquely upward at predetermined intervals, each of which a bag-shaped nut 11 is mounted. Figure 1B As shown, elastic pressing parts 15 are fixed on the main shaft 13, approximately parallel to the support rod 14. Pocket nuts 11 are inserted into these support rods 14 and elastic pressing parts 15, as shown. Figure 1A As shown, multiple pocket nuts 11 are held in a tree-like arrangement on the impregnated retainer 12. Then, as... Figure 2 As shown, in this state, it is immersed in a specified liquid tank 16 for electroplating. When the specified treatment is completed, the immersion retainer 12 and the treated bag nut 11 are lifted out of the liquid tank 16 together.

[0004] In addition, in Patent Document 1, an exhaust passage is provided in the immersion holder 12 to exhaust the air sealed inside the bag-shaped workpiece to the outside, thereby improving the electroplating effect and efficiency of the inner surface of the bag-shaped workpiece.

[0005] As described above, in the electroplating method for bag-shaped workpieces described in Patent Document 1, electroplating of the inner surface of the workpiece can also be carried out well. However, depending on the workpiece, electroplating of the inner surface of the workpiece is sometimes not particularly necessary. In this case, if the amount of electroplating deposited on the inner surface of the workpiece can be reduced, electroplating materials can be saved accordingly, and costs can be reduced. Summary of the Invention

[0006] In view of the above problems, the object of the present invention is to provide an electroplating method, particularly in cylindrical workpieces, that can reduce the amount of electroplating deposits inside the workpiece.

[0007] The technical details described herein are not intended to explicitly or implicitly limit the invention described in the claims, nor are they intended to limit the invention described in the claims to persons other than those who benefit from this invention (e.g., the applicant and the patentee). They are merely described for the purpose of facilitating a clear understanding of the essential points of the invention. A summary of the invention from other perspectives can be understood, for example, from the scope of the claims at the time of filing the patent application.

[0008] The electroplating method of the present invention is a wet electroplating method for tubes (also referred to as cylindrical workpieces in this specification) that are rigid bodies. The wet electroplating method involves electroplating the object to be processed in a solution in which metal is dissolved. The tube is open at both ends along its axial direction. Although the term "tube" is used, the length of the tube is not necessarily longer than its width. Examples of tubes include, but are not limited to, the oval-shaped metal casing of a USB (universal serial bus) Type-C connector (i.e., the metal part used for connector connection). Of course, the metal casing is electroplated before the finished USB Type-C connector is inserted.

[0009] Before electroplating, the tube is mounted on a power supply fixture. The power supply fixture has a shape formed by bending a metal sheet. As part of the power supply fixture, a baffle plate (also referred to as a restraint section in this specification) is located inside the tube when it is mounted on the fixture. The tube mounted on the power supply fixture is electroplated in a solution in which metal has been dissolved. The baffle plate obstructs the flow of the electroplating solution entering axially along the tube during the electroplating process.

[0010] Invention Effects

[0011] According to the present invention, the amount of electroplating deposits inside the cylindrical workpiece can be reduced, thereby saving electroplating materials accordingly. Attached Figure Description

[0012] Figure 1A This is a diagram showing the installation state of a workpiece in a conventional example of an electroplating method.

[0013] Figure 1B This is a diagram showing the mounting of a workpiece in a conventional example of an electroplating method.

[0014] Figure 2 It means to Figure 1A The diagram shows the action of the immersion retainer being immersed in the liquid tank.

[0015] Figure 3A This is a front view of the carrier used in the embodiment.

[0016] Figure 3B This indicates that the cylindrical workpiece is installed... Figure 3A A front view of the state of the carrier shown.

[0017] Figure 4A It is Figure 3A An enlarged 3D view of the portion of the carrier where a power supply clamp is located.

[0018] Figure 4B yes Figure 4A The front view of the part shown.

[0019] Figure 4C yes Figure 4A The side view of the part shown.

[0020] Figure 5A It means in Figure 4A The first example of the power supply fixture shown is a perspective view of a cylindrical workpiece mounted on it.

[0021] Figure 5B Is Figure 4A The first example of the power supply fixture shown is a front view of the cylindrical workpiece mounted on it.

[0022] Figure 5C yes Figure 5B The D-D line cross-section.

[0023] Figure 6A This is a process diagram of an embodiment.

[0024] Figure 6B These are process diagrams for other embodiments.

[0025] Figure 7A It means Figure 6A or Figure 6B The diagram shows the process of "extracting the carrier from the reel".

[0026] Figure 7B It means Figure 6B The diagram shows the process of "winding a carrier with a workpiece onto a reel".

[0027] Figure 8 This is a process diagram of yet another embodiment.

[0028] Figure 9A This is a perspective view showing the second example of a power supply clamp.

[0029] Figure 9B yes Figure 9A The front view of the power supply clamp shown.

[0030] Figure 9C yes Figure 9A Side view of the power supply clamp shown.

[0031] Figure 10A It means in Figure 9AThe second example of the power supply fixture shown is a perspective view of a cylindrical workpiece mounted on it.

[0032] Figure 10B Is Figure 9A The second example of the power supply fixture shown is a front view of a cylindrical workpiece mounted on it.

[0033] Figure 10C yes Figure 10B The D-D line cross-section.

[0034] Figure 11A This is a perspective view of the third example of a power supply clamp.

[0035] Figure 11B yes Figure 11A The front view of the power supply clamp shown.

[0036] Figure 11C yes Figure 11A Side view of the power supply clamp shown.

[0037] Figure 12A It means in Figure 11A The third example of the power supply fixture shown is a perspective view of a cylindrical workpiece mounted on it.

[0038] Figure 12B Is Figure 11A The third example of the power supply fixture shown is a front view of a cylindrical workpiece mounted on it.

[0039] Figure 12C yes Figure 12B The D-D line cross-section.

[0040] Figure 13A This is a perspective view of the fourth example of a power supply clamp.

[0041] Figure 13B yes Figure 13A The front view of the power supply clamp shown.

[0042] Figure 13C yes Figure 13A Side view of the power supply clamp shown.

[0043] Figure 14A It means in Figure 13A The fourth example of the power supply fixture shown is a perspective view of a cylindrical workpiece mounted on it.

[0044] Figure 14B Is Figure 13A The fourth example of the power supply fixture shown is a front view of a cylindrical workpiece mounted on it.

[0045] Figure 14C yes Figure 14B The D-D line cross-section.

[0046] Figure 15A This is a perspective view of the fifth example of a power supply clamp.

[0047] Figure 15B yes Figure 15A The front view of the power supply clamp shown.

[0048] Figure 15C yes Figure 15A Side view of the power supply clamp shown.

[0049] Figure 16A It means in Figure 15A The fifth example of the power supply fixture shown is a perspective view of a cylindrical workpiece mounted on it.

[0050] Figure 16B Is Figure 15A The fifth example of the power supply fixture shown is a front view of a cylindrical workpiece mounted on it.

[0051] Figure 16C yes Figure 16B The D-D line cross-section.

[0052] Figure 17A This is a perspective view of the sixth example of a power supply clamp.

[0053] Figure 17B yes Figure 17A The front view of the power supply clamp shown.

[0054] Figure 17C yes Figure 17A Side view of the power supply clamp shown.

[0055] Figure 18A It means in Figure 17A The sixth example of the power supply fixture shown is a perspective view of a cylindrical workpiece mounted on it.

[0056] Figure 18B Is Figure 17A The sixth example of the power supply fixture shown is a front view of a cylindrical workpiece mounted on it.

[0057] Figure 18C yes Figure 18B The D-D line cross-section.

[0058] Explanation of reference numerals in the attached figures

[0059] 11: Pocket Nut

[0060] 12: Impregnation retainer

[0061] 13: Main shaft

[0062] 14: Support rod section

[0063] 15: Elastic Pushing Section

[0064] 16: Liquid tank

[0065] 20: Power supply clamp

[0066] 20': Power supply clamp

[0067] 20”: Power supply clamp

[0068] 21: Elastic contact sheet

[0069] 22: Elastic contact piece

[0070] 21a: Contact part

[0071] 22a: Contact part

[0072] 22b: Edge

[0073] 22c: Edge

[0074] 23: Incision

[0075] 24: Inhibition section

[0076] 30: Cylindrical workpiece

[0077] 30': Cylindrical workpiece

[0078] 30”: Cylindrical workpiece

[0079] 50: Power supply clamp

[0080] 50': Power supply clamp

[0081] 50”: Power supply clamp

[0082] 51: Inhibition section

[0083] 52: Elastic contact piece

[0084] 53: Elastic contact piece

[0085] 54: Flexible contact sheet

[0086] 52a: Contact part

[0087] 53a: Contact part

[0088] 54a: Contact part

[0089] 55: Plate section

[0090] 100: Carrier

[0091] 101: Guide hole

[0092] 102: Guide hole

[0093] 200: Scroll

[0094] 300: Scroll Detailed Implementation

[0095] The embodiments are described with reference to the accompanying drawings.

[0096] Figure 3A This refers to the carrier used in one embodiment of the electroplating method for cylindrical workpieces of the present invention. The carrier 100 is a long strip. Figure 3A The image only represents a portion of it. On the carrier 100, a plurality of power supply clamps 20 for mounting cylindrical workpieces are arranged in a row at a specified interval and integrally formed. The carrier 100 is formed, for example, by cutting a metal plate such as a stainless steel plate into a specified shape and bending it. Figure 3A In the diagram, 101 and 102 represent guide holes, respectively.

[0097] Figure 4A , 4B Figure 4C is a partially enlarged view of the portion of the carrier 100 where a power supply clamp 20 is located. In this example, the power supply clamp 20 has a U-shaped bend, with the two legs forming the U functioning as elastic contact pieces 21 and 22, respectively. Contact portions 21a and 22a, bent in a mutually outwardly projecting manner, are formed on these two elastic contact pieces 21 and 22. Furthermore, in this example, as... Figure 4A , 4B As shown in 4C, a cutout 23 is provided in the middle part of the U-shaped part, which, as described later, functions as a suppressing part 24 to suppress the flow of electroplating solution.

[0098] Electroplating of the cylindrical workpiece is performed by mounting the cylindrical workpiece on each of the power supply fixtures 20 of the carrier 100 and immersing it in a circulating electroplating solution. Figure 3B This indicates the state in which the cylindrical workpiece 30 is mounted on each power supply fixture 20. In this example, the cylindrical workpiece 30 is a component of the connector, namely a stainless steel housing, which is nickel-plated.

[0099] The cylindrical workpiece 30 is installed into the power supply clamp 20 by inserting the power supply clamp 20 into one of the openings of the cylindrical workpiece 30, which is open at both ends axially. Thus, as... Figure 5A , 5BAs shown in Figure 5C, the two elastic contact pieces 21 and 22 of the power supply fixture 20 elastically contact the two opposite surfaces of the inner surface of the cylindrical workpiece 30 in a mutually outward opening manner, thereby holding the cylindrical workpiece 30 and supplying power to it. Furthermore, since contact portions 21a and 22a are provided on the two elastic contact pieces 21 and 22 protruding outward from each other, these contact portions 21a and 22a can achieve stable and good contact with the inner surface of the cylindrical workpiece 30.

[0100] The carrier 100 performs the required feeding and lifting actions via a drive device (not shown). The carrier 100 undergoes at least the following steps in sequence: an installation process, in which the cylindrical workpiece 30 is installed on each of the power supply fixtures 20 as described above; an electroplating process, in which the cylindrical workpiece 30 installed on the power supply fixtures 20 is passed through an electroplating tank containing electroplating solution; and a recycling process, in which the electroplated cylindrical workpiece 30 is removed from the power supply fixtures 20. By using such a carrier 100, continuous electroplating of the cylindrical workpiece 30 can be performed in this example.

[0101] In the electroplating process, a power source is connected to the carrier 100 and the anode disposed in the electroplating tank. A positive voltage is applied to the anode, and a negative voltage is applied to the carrier 100, thereby performing electroplating. The cylindrical workpiece 30, with its axial direction, for example, vertical, is immersed in a circulating electroplating solution. Here, as... Figure 5B As shown, the suppressing part 24 of the power supply clamp 20 inserted into the interior of the cylindrical workpiece 30 is located inside the cylindrical workpiece 30, blocking the space to a certain extent. Therefore, the axial flow of the electroplating solution is suppressed by the suppressing part 24. As a result, in this example, the amount of electroplating deposited inside the cylindrical workpiece 30 is reduced.

[0102] Thus, in the electroplating process, in order to reduce the amount of electroplating deposits inside the cylindrical workpiece 30, the flow of electroplating solution inside the cylindrical workpiece 30 is suppressed by the suppression part 24 of the power supply fixture 20, while electroplating is performed on the cylindrical workpiece 30. As a result, electroplating materials can be saved in this example.

[0103] Furthermore, the amount of electroplating deposited on the inner surface of the cylindrical workpiece 30 can be reduced; that is, even if the inner surface is electroplated, the coating thickness on the inner surface can be reduced. Therefore, compared to the case of a larger film thickness, the deviation in film thickness is smaller, which means that the deviation in internal dimensions between the individual cylindrical workpieces 30 after electroplating can be reduced. This allows for better assembly operations, such as in assembly processes after inserting components into the cylindrical workpiece 30.

[0104] The size of the suppression part 24 of the power supply fixture 20 is an area that occupies more than 30% and less than 90% of the area of ​​the opening on one or the other side of the cylindrical workpiece 30 when viewed from the axial direction of the cylindrical workpiece 30.

[0105] Before mounting the cylindrical workpiece 30, the carrier 100 is, for example, wound on a spool. The carrier 100 is pulled out from the spool, and the cylindrical workpiece 30 is mounted on each of the power supply clamps 20 of the carrier 100, thereby performing the required electroplating process.

[0106] Figure 6A The diagram illustrates the process in this case, with steps 41-47. Steps 41-47 sequentially involve carrier extraction from the reel, workpiece mounting, degreasing, electroplating, drying, workpiece recovery, and winding the carrier back onto the reel. These steps 41-47 constitute a so-called reel-to-reel electroplating process. Furthermore, workpiece mounting in step 42 and workpiece recovery in step 46 can also be performed using automated equipment.

[0107] exist Figure 6A In the process shown, in the final step 47, the carrier from which the workpiece has been removed is wound onto a reel, but it can also be done as follows: Figure 6B In processes 41-45 and 48, the workpiece is not removed, and in the final process 48, the carrier is wound onto a spool with the workpiece still attached. This method is suitable for assembling the electroplated cylindrical workpiece 30 into the product being used in an automated machine.

[0108] Figure 7A It indicates that the carrier is from Figure 6A , 6B The diagram shows the reel extraction process in step 41, where 200 represents the reel. Additionally, Figure 7B express Figure 6B In step 48, the carrier carrying the workpiece is wound on a reel. In the figure, 300 represents the reel.

[0109] Alternatively, the carrier 100 can be formed into a closed ring, allowing the carrier 100 to continuously undergo electroplating in a loop. Figure 8 The diagram shows the steps in this case, with steps 42 to 46 and 49 representing the steps in sequence. In this example, after the workpiece is recovered in step 46, the electroplated layer deposited on the carrier is removed in step 49. After step 49, the process returns to step 42 to install the workpiece onto the carrier again. The carrier 100 repeats this process, going through steps 42 to 46 and 49.

[0110] In step 49, the removal of the electroplated layer deposited on the carrier can be carried out, for example, by immersing the carrier 100 in an electrolyte to induce an electrochemical reaction opposite to electroplating. The electroplated material removed from the carrier 100 is reused.

[0111] Furthermore, as described above, the amount of electroplating deposited inside the cylindrical workpiece 30 is reduced by the suppression portion 24 of the power supply fixture 20, thus making it difficult for the electroplated layer to adhere to the power supply fixture 20. Therefore, for example, in Figure 6AIn the illustrated process, to save on electroplating materials, a recovery operation is performed on the electroplated layer deposited on the carrier 100. However, since the amount of electroplated material deposited is small, for example, the operation of removing the electroplated layer from the carrier 100 and recovering the electroplating materials can be performed after multiple electroplating processes. Therefore, the recovery cost can be reduced.

[0112] The shape of the power supply clamp mounted on the carrier 100 is not limited to... Figure 4A , 4B The shape shown in 4C can also be other shapes. Figure 9A , 9B 9C, 11A, 11B, 11C, 13A, 13B, 13C, 15A, 15B, 15C, 17A, 17B, and 17C represent other shapes of power supply clamps. Figure 10A , 10B 10C, 12A, 12B, 12C, 14A, 14B, 14C, 16A, 16B, 16C, 18A, 18B, and 18C respectively represent the values ​​in... Figure 9A , 9B The power supply fixtures shown in 9C, 11A, 11B, 11C, 13A, 13B, 13C, 15A, 15B, 15C, 17A, 17B, and 17C are in a state where a cylindrical workpiece is mounted on it.

[0113] Figure 9A , 9B The power supply clamp 20' shown in 9C has a U-shaped bend, which is used for... Figure 4A , 4B The parts corresponding to the power supply clamp 20 shown in Figures 4C are marked with the same reference numerals. In this example, there is no cutout in the middle part of the U-shape that constitutes the suppression part 24, and the two legs of the U-shape constitute two elastic contact pieces 21 and 22.

[0114] Figure 11A , 11B The power supply clamp 50 shown in 11C consists of a suppression part 51 and two elastic contact pieces 52 and 53. When the cylindrical workpiece 30' is inserted, the suppression part 51 becomes a flat plate that intersects the axial direction of the cylindrical workpiece 30'. The two elastic contact pieces 52 and 53 are formed on the bent and extended portion of one side of the flat plate, extending toward the insertion direction of the cylindrical workpiece 30'.

[0115] Figure 13A , Figure 13B , Figure 13C The power supply clamp 50' shown is Figure 11A , Figure 11B , Figure 11CThe power supply clamp 50 shown also has a suppressing portion 51 formed by a flat plate and two elastic contact pieces 52, 53 provided on the bent and extended portion of one side of the flat plate. However, in this power supply clamp 50', as... Figure 13A As shown, the two elastic contact pieces 52 and 53 are shaped such that after extending in the insertion direction toward the cylindrical workpiece, they bend outward toward each other and fold back toward the inhibition part 51.

[0116] Figure 15A , 15B The power supply clamp 20" shown in 15C and Figure 4A , 4B Similarly, the power supply clamp 20 shown in 4C has a U-shaped bend, with two elastic contact pieces 21 and 22 formed by the two legs of the U. However, the portion of one elastic contact piece 21 that reaches its front end (free end) gradually narrows into a trapezoidal shape. This trapezoidal portion is slightly raised (bent up) away from the other elastic contact piece 22, and a contact portion 21a is formed at its front end.

[0117] On the other side of the elastic contact piece 22 and with Figure 4A , 4B The power supply fixture 20 shown in Figure 4C also has a contact portion 22a, but in this power supply fixture 20", when inserting the cylindrical workpiece 30", as Figure 16B , 16C As shown, the edge portions 22b and 22c at both ends of the contact portion 21a and the contact portion 22a in the width direction are in contact with the inner surface of the cylindrical workpiece 30". In addition, the suppression portion 24 is provided with a notch 23 in the same way as the power supply fixture 20.

[0118] Figure 17A , 17B The power supply clamp 50" shown in 17C and Figure 11A , 11B Similarly, the power supply clamp 50 shown in 11C has a suppressing portion 51 composed of a flat plate and two elastic contact pieces 52 and 53, and the power supply clamp 50" has a third elastic contact piece 54. The elastic contact piece 54 is formed by extending between the elastic contact pieces 52 and 53 in the same way, and has a plate surface of a plate portion 55 that is bent and extended relative to one side of the suppressing portion 51, with the middle portion located slightly above. This middle portion functions as the contact portion 54a.

[0119] On the other hand, such as Figure 17A , 17B As shown in 17C, the elastic contact pieces 52 and 53 are formed by extending obliquely downward from the plate portion 55, and respectively have contact portions 52a and 53a that are bent into arc shapes at their front ends.

[0120] When the power supply fixture 50" is inserted into the cylindrical workpiece 30', if Figure 18B , 18C As shown, contact portions 52a, 53a and 54a are in contact with the inner surface of the cylindrical workpiece 30'.

[0121] The above describes other shapes of power supply clamps, but in these power supply clamps of 20', 50, 50', 20", and 50", they are also respectively as shown in the examples. Figure 10A , 10B As shown in 10C, 12A, 12B, 12C, 14A, 14B, 14C, 16A, 16B, 16C, 18A, 18B, and 18C, multiple elastic contact pieces elastically contact the inner surface of the cylindrical workpiece to hold the cylindrical workpiece in place and can supply power to the cylindrical workpiece. In addition, the suppressing part is located inside the cylindrical workpiece and can suppress the flow of the electroplating solution.

Claims

1. A method for electroplating a cylindrical workpiece, comprising immersing the cylindrical workpiece, which is fitted with a power supply fixture, in a circulating electroplating solution to electroplat the cylindrical workpiece, the method comprising: Installation process: The cylindrical workpiece is installed in the power supply clamp by inserting the power supply clamp into the interior of the cylindrical workpiece through an axial opening at one end; wherein the power supply clamp is formed by bending a metal plate and has multiple elastic contact pieces and a suppressing part, each of the elastic contact pieces elastically contacts the inner surface of the cylindrical workpiece to hold the cylindrical workpiece and is capable of supplying power to the cylindrical workpiece, and the suppressing part is located inside the cylindrical workpiece to suppress the axial flow of the electroplating solution; Electroplating process: The cylindrical workpiece, equipped with the power supply fixture, is passed through an electroplating tank containing circulating electroplating solution, thereby electroplating the cylindrical workpiece while the flow of the electroplating solution inside the cylindrical workpiece is suppressed by the inhibition part; and Recycling process: The electroplated cylindrical workpiece is removed from the power supply fixture; Its features are: The electroplating method for the cylindrical workpiece involves circulating a carrier with a closed-loop structure and multiple power supply fixtures arranged thereon to perform continuous electroplating. In the cyclical operation, the carrier repeatedly undergoes processes in this sequence, including at least the following steps: The installation process, the electroplating process, the recycling process, and the electroplating removal process for removing the electroplated layer deposited on the carrier.

2. The electroplating method for a cylindrical workpiece as described in claim 1, characterized in that, The plurality of elastic contact pieces are two elastic contact pieces. The power supply clamp has a U-shaped bend, with the middle part of the U forming the suppression part and the two legs of the U forming the two elastic contact pieces.

3. The electroplating method for a cylindrical workpiece as described in claim 1, characterized in that, The plurality of elastic contact pieces are two elastic contact pieces. The power supply clamp has a U-shaped shape, with the middle part of the U-shape forming the suppression part and the two legs of the U-shape forming the two elastic contact pieces.

4. The electroplating method for a cylindrical workpiece as described in claim 1, characterized in that, The suppression portion is a flat plate portion that intersects the axial direction, and the plurality of elastic contact pieces are disposed on a bent and extended portion of one side of the flat plate portion.

5. The electroplating method for a cylindrical workpiece as described in any one of claims 1 to 4, characterized in that, The size of the suppression portion is an area that occupies more than 30% and less than 90% of the area of ​​one or the other opening when viewed from the axial direction.

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