Plating apparatus

Abstract

Provided is a plating device in which, even if the flow rate of a plating solution ejected from an ejection unit is increased, a plated object does not excessively rise to a high position in the stored plating solution, and the occurrence of defects in the plated object is suppressed. A plating device is provided with: a plating tank for storing a plating solution containing an object to be plated; and a spraying part which is formed in the plating tank, has a first spraying port for spraying the plating liquid, and stirs the object to be plated contained in the plating liquid by the plating liquid sprayed from the spraying part, in which a screen member is provided at the first spraying port of the spraying part, the screen member is formed by overlapping at least two screens, and the screen member is provided with a plurality of screen holes in the screen member when viewed in the plane direction. The screen has a central portion and a peripheral portion provided on the outside of the central portion, the peripheral portion is formed of one screen layer or a plurality of screen layers, the central portion is formed of a plurality of screen layers, and the number of screen layers in the central portion is larger than the number of screen layers in the peripheral portion.

Description

Technical Field

[0001] The present invention relates to a plating apparatus. Background Art

[0002] So-called jet-type plating apparatuses are widely used for forming external electrodes of electronic components, etc. Patent Document 1 (Japanese Patent Application Laid-Open No. 2021-138999) discloses a jet-type plating apparatus.

[0003] The plating device disclosed in Patent Document 1 includes a plating tank. The plating tank contains a metal tube (cathode) as a first electrode, a partition tube made of an insulating material, and a second electrode (anode). In addition, a plurality of small holes are formed in the partition tube so that the plating solution can pass through but the plated object, medium, etc. cannot pass through.

[0004] A metal tube is arranged inside the partition tube, and a plating forming portion is formed between the inner side of the partition tube and the outer side of the metal tube. The plating forming portion refers to a region (space) where plating is applied to the object to be plated. A second electrode is arranged outside the partition tube.

[0005] A jetting unit having a jetting port for jetting the plating liquid is provided below the metal pipe. The jetting unit is used to generate an upward flow of the plating liquid inside the metal pipe. In addition, although not disclosed in the plating device of Patent Document 1, a screen member is usually provided at the jetting port of the jetting unit so that the plated object and the medium do not fall into the jetting unit when the jetting stops.

[0006] The plating device disclosed in Patent Document 1 contains a plating solution in a plating tank. Next, an object to be plated, a conductive medium, and, if necessary, insulating balls are put into the plating tank containing the plating solution. However, the plating solution may be contained in the plating tank after the object to be plated, the medium, and the insulating balls are put into the plating tank. In addition, the medium is used to electrically connect the metal tube that serves as the first electrode in the plating of the object to be plated in the plating forming section and the plating forming area (area where the base electrode, etc. are formed) on the surface of the object to be plated. The insulating balls are used to improve the fluidity of the object to be plated circulating in the plating device.

[0007] The object to be plated, the dielectric, and the insulating ball rise inside the metal pipe along with the upward flow of the plating solution inside the metal pipe generated by the jetting portion, are ejected outward from the upper end of the metal pipe, and are stirred in the plating solution.

[0008] The stirred object to be plated, dielectric, and insulating balls are then deposited on the upper side of the plating formation portion. At this time, other objects to be plated, dielectrics, and insulating balls are already deposited in the plating formation portion. The objects to be plated, dielectrics, and insulating balls deposited on the upper side of the plating formation portion then gradually descend in the plating formation portion. At this time, a plating film is formed in the plating formation area on the surface of the object to be plated by applying a current between the metal tube as the first electrode and the second electrode.

[0009] The object to be plated, dielectric, and insulating balls with the plated film formed thereon are pushed out from the lower end of the plated forming part, and rise again inside the metal pipe along with the rising flow of the plating liquid generated inside the metal pipe, and are ejected outward from the upper end of the metal pipe and stirred. Then, the stirred object to be plated, dielectric, and insulating balls are deposited on the upper side of the plated forming part in the same manner as last time, and then gradually descend in the plated forming part, and a plated film is formed on the object to be plated during the descent.

[0010] The object to be plated may circulate in the plating apparatus several to several thousand times until the plated film reaches a predetermined thickness and the plating process is completed.

[0011] Prior Art Literature

[0012] Patent Literature

[0013] Patent Document 1: Japanese Patent Application Publication No. 2021-138999 Summary of the invention

[0014] Problem that the invention aims to solve

[0015] Plating on an object to be plated needs to satisfy the following (a) and (b).

[0016] (a) A plated film having a thickness greater than or equal to a predetermined thickness is formed on each object to be plated.

[0017] (b) The variation in thickness of the plated film formed between a plurality of objects to be plated simultaneously is small (within a predetermined allowable value).

[0018] In one (one batch) plating process, when the time from the start of plating to the end of plating is defined as the "total plating time", if the total plating time is fixed, even if the time required for the plated object to pass through the plating forming section once and the number of times the plated object passes through the plating forming section change, the thickness of the plated film formed on each plated object is substantially the same. This is because the thickness of the plated film formed on the plated object depends on the total time for each plated object to pass through the plating forming section (the time required to pass through the plating forming section once × the number of times it passes). In addition, of course, when the total plating time is fixed, if the time required for the plated object to pass through the plating forming section once becomes longer, the number of times the plated object passes through the plating forming section becomes fewer, and if the time required for the plated object to pass through the plating forming section once becomes shorter, the number of times the plated object passes through the plating forming section becomes more.

[0019] On the other hand, when the total plating time is fixed, when the time required for the object to be plated to pass through the plating forming section once is shortened, thereby increasing the number of times the object to be plated circulates in the plating device, the variation in the thickness of the plated film formed between the plurality of objects to be plated becomes smaller than when the time required for the object to be plated to pass through the plating forming section once is lengthened, thereby reducing the number of times the object to be plated circulates in the plating device. That is, each time the object to be plated passes through the plating forming section once, the thickness of the plated film formed (grown) on the object to be plated varies depending on whether the object to be plated passes near the metal tube, near the next-wall tube, or near the middle of the metal tube and the next-wall tube, and therefore, by increasing the number of times the object passes to achieve equalization, the variation in the thickness of the plated film formed can be reduced.

[0020] Considering the productivity of the plating process, it is preferred that the total plating time is short. In order to increase the number of times the plated object passes through the plating forming portion within the limited total plating time, it is sufficient to increase the flow rate of the plating solution sprayed from the spray portion. In order to increase the flow rate of the plating solution sprayed from the spray portion, for example, it is sufficient to increase the output of a pump connected to the spray portion.

[0021] However, if the flow rate of the plating solution sprayed from the spraying part is increased, there is a case where "cracks" or "defects" occur in the object to be plated, or "peeling" occurs in the plating film formed on the object to be plated, etc., resulting in defects in the object to be plated. It is believed that the reason is that if the flow rate of the plating solution sprayed from the spraying part is increased, the speed of the object to be plated rising in the metal pipe as the first electrode becomes too fast, and the object to be plated sprayed outward from the upper end of the metal pipe rises to a higher position in the plating solution stored in the plating tank and collides with a reflector called a deflector, or collides with the inner wall of the plating tank or other objects to be plated when descending (settling) from a higher position in the plating solution. That is, the object to be plated is discharged outward from the upper end of the metal pipe together with the dielectric and the insulating ball in order to stir them, but at this time, if the object to be plated rises to a higher position in the stored plating solution too quickly, sometimes defects occur in the object to be plated.

[0022] Therefore, an object of the present invention is to provide a plating apparatus that prevents an object to be plated from excessively rising to a high position in a stored plating solution even when the flow rate of the plating solution sprayed from a spray portion is increased, thereby suppressing occurrence of defects in the object to be plated.

[0023] Technical solutions to solve problems

[0024] In order to solve the above-mentioned conventional problems, a plating device involved in one embodiment of the present invention comprises: a plating tank storing a plating liquid containing an object to be plated; and a spray portion formed in the plating tank and having a first spray port for spraying the plating liquid, wherein the object to be plated contained in the plating liquid is stirred by the plating liquid sprayed from the spray portion, wherein a screen member is provided at the first spray port of the spray portion, the screen member is formed by overlapping at least two screens, and when the screen member is observed in a planar direction, has a central portion and a peripheral portion provided on the outer side of the central portion, the peripheral portion is formed by one screen layer or a plurality of screen layers, and the central portion is formed by a plurality of screen layers, and the number of screen layers in the central portion is greater than the number of screen layers in the peripheral portion.

[0025] Effects of the Invention

[0026] In a plating apparatus according to an embodiment of the present invention, even if the flow rate of the plating solution ejected from the ejector is increased, the object to be plated does not rise excessively to a high position in the stored plating solution, thereby suppressing the occurrence of defects in the object to be plated.

[0027] The speed of the plating solution passing through the inside of the metal tube as the first electrode (rising inside the metal tube) is not uniform throughout the entire cross-section of the metal tube, but is faster toward the center of the metal tube and slower toward the peripheral portion close to the inner wall of the metal tube. This is because resistance is generated in the flow of the plating solution at the peripheral portion close to the inner wall of the metal tube, which can suppress the speed of the plating solution.

[0028] In addition, in a case where an inner cylindrical injection portion is provided on the bottom surface of a plating tank of a plating device, a first injection port is provided on the upper side of the injection portion, and a second injection port for injecting a plating liquid into the injection portion is provided on the bottom surface of the injection portion, and in a case where the diameter of the second injection port is smaller than the inner diameter of the metal tube, the plating liquid sometimes flows faster toward the center of the metal tube and flows slower toward the peripheral portion closer to the inner wall of the metal tube.

[0029] On the other hand, when the flow rate of the plating solution sprayed from the spraying part is increased, not all the objects to be plated sprayed outward from the upper end of the metal pipe rise to a higher position in the plating solution stored in the plating tank. It is considered that the objects to be plated that rise to a higher position in the plating solution stored in the plating tank are mainly objects to be plated that pass through (rise) at once in the center of the metal pipe where the speed of the plating solution is high.

[0030] In a plating device according to one embodiment of the present invention, the speed of the plating liquid passing through (rising) inside the metal tube is suppressed at the center of the metal tube. Therefore, even if the flow rate of the plating liquid sprayed from the spray portion is increased, the object to be plated will not excessively rise to a higher position in the stored plating liquid, thereby suppressing the occurrence of defects in the object to be plated. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a cross-sectional view of the plating apparatus 100 according to the embodiment.

[0032] Figure 2 is a cross-sectional view of the plating apparatus 100, showing Figure 1 The single-dash arrow AA part.

[0033] Figure 3 It is a cross-sectional view of a main part of the plating apparatus 100 .

[0034] Figure 4 (A) is a plan view of the mesh member 7 of the plating apparatus 100 . Figure 4 (B) is a plan view of a mesh member 7 ′ which is a modified example of the mesh member 7 . DETAILED DESCRIPTION

[0035] The following, with the attached Figure 1 The following describes a mode for carrying out the present invention.

[0036] In addition, each embodiment illustratively shows an embodiment of the present invention, and the present invention is not limited to the contents of the embodiment. In addition, it is also possible to combine the contents recorded in different embodiments to implement, and the implementation contents in this case are also included in the present invention. In addition, the drawings are used to help the understanding of the specification, and are sometimes schematically depicted, and the ratio of the dimensions of the depicted constituent elements or constituent elements is sometimes inconsistent with the ratio of their dimensions recorded in the specification. In addition, there are cases where the constituent elements recorded in the specification are omitted in the drawings, and the number of elements is omitted and depicted, etc.

[0037] exist Figure 1 , Figure 2 , Figure 3 , Figure 4 (A) and (B) show the plating device 100 according to the embodiment. Figure 1 2 is a cross-sectional view of the plating apparatus 100 . Figure 2 is also a cross-sectional view of the plating apparatus 100, showing Figure 1 The AA portion is indicated by the single-dot dash arrow. Figure 3 It is a cross-sectional view of a main part of the plating apparatus 100 . Figure 4 (A) is a plan view of the mesh member 7 of the plating apparatus 100 . Figure 4 (B) is a plan view of a mesh member 7 ′ which is a modified example of the mesh member 7 .

[0038] The plating apparatus 100 includes a plating tank 1. The top of the plating tank 1 is open. The plating tank 1 is used to store a mixture 16 of a plating solution, an object to be plated, a medium, and insulating balls described later. However, the insulating balls may be omitted if not necessary.

[0039] The plating device 100 includes a cylindrical metal pipe 2 inside a plating tank 1. The metal pipe 2 has a hollow portion 2a. The metal pipe 2 is a first electrode, and in the present embodiment, is a cathode electrode. In the present embodiment, the metal pipe 2 is cylindrical. However, the metal pipe 2 may also be a polygonal cylindrical shape. The material of the metal pipe 2 is arbitrary, and various metals may be used.

[0040] In the present embodiment, two rod-shaped conductive support parts 2b are formed integrally with the metal pipe 2 at the upper part of the metal pipe 2. However, the number of the support parts 2b is arbitrary and is not limited to two.

[0041] The plating device 100 is provided with a bulkhead tube 3 made of an insulating material inside the plating tank 1. The bulkhead tube 3 has a hollow portion 3a. In the present embodiment, the bulkhead tube 3 is cylindrical. However, the bulkhead tube 3 may also be a polygonal cylindrical shape. A plurality of small holes 3b are formed in the bulkhead tube 3, which allow the plating solution to pass through but do not allow the plated object, the medium, and the insulating ball to pass through. When an electric current is applied between the metal tube 2 as the first electrode and the second electrode 5, the hole 3b allows the electric current to pass through using the plating solution as a medium. The material of the bulkhead tube 3 is arbitrary, for example, various resins can be used.

[0042] The inner diameter of the partition tube 3 is larger than the outer diameter of the metal tube 2. The metal tube 2 is arranged in the hollow portion 3a of the partition tube 3. A plating forming portion 4 is formed between the inner side of the partition tube 3 and the outer side of the metal tube 2. The plating forming portion 4 is a region (space) where plating is applied to the object to be plated. Figure 1 , Figure 2 , Figure 3 In FIG. 1 , the plating forming portion 4 is depicted in a grid shape.

[0043] The object to be plated, the dielectric, and the insulating balls are accumulated inside the plating forming portion 4 and gradually fall downward. During the fall, the surface of the object to be plated is plated.

[0044] The plating device 100 includes a second electrode 5 inside the plating tank 1. In the present embodiment, the second electrode 5 is an anode electrode. In the present embodiment, the second electrode 5 includes a cylindrical metal. The second electrode 5 is arranged outside the partition tube 3. The material of the second electrode 5 is arbitrary, and various metals can be used.

[0045] like Figure 2 As shown, when the plating device 100 is viewed in the planar direction, the metal tube 2, the partition tube 3, and the second electrode 5 are arranged in a concentric circle shape so that their central axes are aligned. Therefore, the plating device 100 uniformly applies current between the metal tube 2 as the first electrode and the second electrode 5 in any area of ​​the plating forming portion 4, thereby suppressing the thickness deviation of the formed plated film.

[0046] The plating device 100 includes a jet part 6 below the metal pipe 2. The jet part 6 is used to generate an upward flow of the plating solution inside the metal pipe 2. In the present embodiment, the jet part 6 is an inner cylinder having a bottom surface and an inner wall. In the present embodiment, the inner cylinder of the jet part 6 is an inner cylindrical shape. However, the inner cylinder of the jet part 6 is not limited to the inner cylindrical shape, and may be other shapes.

[0047] A first injection port 6a is formed at the upper end of the injection portion 6. A second injection port 6b is formed at the bottom surface of the injection portion 6. The plating liquid is injected into the injection portion 6 from the second injection port 6b. The plating liquid is injected into the plating tank 1 from the first injection port 6a. In the present embodiment, the opening area of ​​the second injection port 6b is smaller than the opening area of ​​the first injection port 6a.

[0048] Furthermore, when the inner diameter of the metal pipe 2 and the diameter of the second injection port 6b are compared, the diameter of the second injection port 6b is smaller than the inner diameter of the metal pipe 2. This also causes the speed of the plating solution in the center of the metal pipe 2 to increase, so a countermeasure to suppress the speed of the plating solution in the center of the metal pipe 2 is required.

[0049] The first injection port 6a of the injection unit 6 is provided with a mesh member 7. The mesh member 7 is provided so that when the injection of the injection unit 6 stops, the plated object, the medium, the insulating ball, etc. do not fall into the injection unit 6. In the present embodiment, the first injection port 6a of the injection unit 6 is circular, and therefore the mesh member 7 is also circular when viewed in the planar direction.

[0050] In the present embodiment, the screen member 7 is formed by overlapping two screens (mesh-shaped members). However, the screen member 7 only needs to be formed by overlapping at least two screens, and may also be formed by overlapping three or more screens. Figure 1 , Figure 3 As shown, the mesh member 7 is formed of a first mesh layer 7a and a second mesh layer 7b.

[0051] The first mesh layer 7a and the second mesh layer 7b are respectively composed of meshes. The first mesh layer 7a and the second mesh layer 7b are preferably insulating. The material of the first mesh layer 7a and the second mesh layer 7b is arbitrary, but nylon can be used, for example. The first mesh layer 7a and the second mesh layer 7b can be set to the following structure, that is, joined by an adhesive, or only overlapped and fixed at the ends.

[0052] When the screen member 7 is observed in the plane direction, Figure 4 As shown in (A), it has a central portion 7c formed by the first mesh layer 7a and the second mesh layer 7b, and a peripheral portion 7d provided outside the central portion 7c and formed only by the first mesh layer 7a.

[0053] In this embodiment, if Figure 4 As shown in (A), the second mesh layer 7b of the central portion 7c is circular. However, the shape of the central portion 7c is arbitrary. For example, it can also be as follows Figure 4 As in the modification shown in (B) of FIG. 7 , the second mesh layer 7 b ′ in the central portion 7 c is formed into a quadrilateral (rectangular) shape or the like.

[0054] The mesh size of the first mesh layer 7a and the mesh size of the second mesh layer 7b may be the same or different. In the present embodiment, a mesh with a mesh size of 900 μm is used for the first mesh layer 7a and the second mesh layer 7b, respectively. The so-called "mesh size" of the mesh is the size between adjacent lines (excluding the wire diameter) in the mesh where the longitudinal lines and the transverse lines intersect. The mesh size is sometimes referred to as the opening (OP) or the opening size.

[0055] When the mesh size is mentioned, it generally refers to the mesh size of one layer of the screen, but in this application document, when multiple screens are overlapped, it sometimes refers to the combined mesh size of the multiple screens. When the mesh size of one layer of the screen is compared with the mesh size when the screen is overlapped in two layers (or the mesh size when the screen and another screen are overlapped), the latter is smaller (finer) than the former.

[0056] In the present embodiment, when the screen member 7 is viewed in the planar direction, the mesh size of the central portion 7c including two layers of screens is smaller than the mesh size of the peripheral portion 7d including one layer of screens. In addition, in the central portion 7c, when the longitudinal lines and the transverse lines of the first screen layer 7a completely overlap with the longitudinal lines and the transverse lines of the second screen layer 7b, the mesh size of the central portion 7c and the mesh size of the peripheral portion 7d become the same, but such a situation does not usually occur.

[0057] The central portion 7c of the mesh member 7 is not limited to a double mesh structure including two layers of mesh. For example, the central portion 7c may be set to a triple mesh structure including three layers of mesh, and the peripheral portion 7d may be set to a single mesh structure including one layer of mesh. Alternatively, an intermediate portion (not shown) may be provided between the central portion 7c and the peripheral portion 7d, the central portion 7c may be set to a triple mesh structure, the intermediate portion may be set to a double mesh structure, and the peripheral portion 7d may be set to a single mesh structure. That is, in the mesh member 7, it is sufficient to increase the number of mesh layers in the portion where the plating solution is particularly desired to be suppressed. In addition, the peripheral portion 7d may be basically a single mesh structure including one layer of mesh, but may also be a multi-mesh structure including multiple layers of mesh. In this way, various deformations may be adopted for the structure of the mesh member 7.

[0058] In this embodiment, if Figure 1 , Figure 3 As shown in the figure, the mesh member 7 is overlapped with the first mesh layer 7a occupying the entire area of ​​the mesh member 7 on the top and the second mesh layer 7b occupying a part of the mesh member 7 on the bottom. In addition, the outer edge of the mesh member 7 is attached to the first injection port 6a. In the first injection port 6a, the plating liquid is injected from the bottom to the top, so as long as it is set to this structure, it is possible to suppress the second mesh layer 7b from peeling off from the first mesh layer 7a.

[0059] In the plating apparatus 100, the momentum of the plating solution passing through the mesh member 7 is suppressed in the central portion 7c including the double mesh structure. In the plating apparatus 100, the momentum of the plating solution ejected from the second ejection port 6b is suppressed by the central portion 7c including the double mesh structure.

[0060] The plating device 100 includes a circulation line 8 formed of a pipe. One end of the circulation line 8 is connected to a liquid suction port 9 formed in the plating tank 1. The other end of the circulation line 8 is connected to the second injection port 6b of the injection unit 6. A pump 10 and a filter 11 are provided in the middle of the circulation line 8. When the pump 10 is driven, the circulation line 8 sucks the plating solution from the liquid suction port 9 and injects the plating solution from the second injection port 6b.

[0061] The plating device 100 is provided with a mixing section 12 below the metal tube 2 and the adjacent tube 3 and above the injection section 6. The mixing section 12 is a region where the plating liquid injected from the first injection port 6a of the injection section 6 and the plated object, the medium, and the insulating balls descending from the plating forming section 4 are mixed. In the present embodiment, the mixing section 12 includes an insulating material and has an inverted frustum-shaped recessed portion formed on the upper surface. In addition, the so-called inverted frustum refers to a frustum whose upper bottom surface is larger than the lower bottom surface. However, the shape of the recessed portion is arbitrary, and may be mortar-shaped or the like instead of the inverted frustum.

[0062] The first injection port 6a of the injection portion 6 is arranged on the bottom surface of the mixing portion 12. As described above, the mesh member 7 is provided at the first injection port 6a of the injection portion 6. Since the mesh member 7 is provided at the first injection port 6a, when the injection of the injection portion 6 stops, the plated object, the medium, the insulating ball, etc. do not fall into the injection portion 6.

[0063] The plating device 100 is provided with a guide portion 13 above the metal pipe 2 and the next-wall pipe 3. In the guide portion 13, the plated object, the medium, and the insulating balls that rise along with the rising flow of the plating liquid formed inside the hollow portion 2a of the metal pipe 2 by the injection from the first injection port 6a of the injection portion 6 and are ejected (discharged) from the opening on the upper side of the hollow portion 2a of the metal pipe 2 are stirred and guided to the area of ​​the plating forming portion 4 after being stirred. The guide portion 13 contains an insulating material and, in the present embodiment, is in the shape of an inverted frustum of a cone. The upper end of the metal pipe 2 protrudes from the bottom surface of the guide portion 13. The upper end of the hollow portion 2a of the metal pipe 2 opens at the bottom surface of the guide portion 13. The bottom surface of the guide portion 13 is connected to the next-wall pipe 3.

[0064] The plating device 100 is provided with an insulating reflector 14 above the opening of the plating tank 1. The reflector 14 is sometimes called a guide plate. The reflector 14 plays a role in suppressing the scattering of the plating solution. In addition, a support portion 2b of the metal pipe 2 is mounted on the lower surface of the reflector 14. In addition, a cylindrical suppression plate 14a is formed on the lower surface of the reflector 14. The suppression plate 14a is arranged in the guide portion 13. The plating solution sometimes overflows from the upper edge of the guide portion 13, but the suppression plate 14a allows only the plating solution to overflow from the guide portion 13, thereby suppressing the overflow of the plated object, the dielectric, and the insulating ball.

[0065] The plating apparatus 100 includes a power source 15. One line of the power source 15 is connected to the support portion 2b of the metal pipe 2 as the first electrode, and the other line is connected to the second electrode 5. The power source 15 applies a current between the metal pipe 2 as the first electrode and the second electrode 5.

[0066] The plating device 100 according to the first embodiment including the above-mentioned structure controls (adjusts) the momentum of the plating solution sprayed from the first spray port 6a of the spray section 6 by the mesh member 7. Specifically, in the central portion 7c formed by overlapping the first mesh layer 7a and the second mesh layer 7b, the momentum of the plating solution sprayed from the first spray port 6a of the spray section 6 and passing through the mesh member 7 is suppressed, compared with the peripheral portion 7d formed only by the first mesh layer 7a.

[0067] As described above, the speed of the plating solution rising inside the metal pipe 2 serving as the first electrode is faster as it approaches the center of the metal pipe 2, and slower as it approaches the peripheral portion of the inner wall of the metal pipe 2. In addition, it is considered that when the flow rate of the plating solution sprayed from the spraying portion 6 is increased, the objects to be plated that are sprayed outward from the upper end of the metal pipe 2 and rise to a higher position in the plating solution stored in the plating tank are mainly the objects to be plated that rise all at once in the center of the metal pipe 2 where the speed of the plating solution is fast.

[0068] In the plating apparatus 100, the momentum of the plating solution sprayed from the first spray port 6a of the spray portion 6 is suppressed in the central portion 7c formed by overlapping the first and second spray ports 6a of the spray portion 6, as compared to the peripheral portion 7d formed by only the first spray port 7a, and thus the momentum of the plating solution rising in the central portion of the metal pipe 2 can be suppressed. More specifically, when the spray amount of the plating solution sprayed from the spray portion 6 is fixed, the plating apparatus 100 can reduce the speed of the plating solution rising in the central portion of the metal pipe 2, as compared to the case where a mesh member composed of one layer of mesh is provided at the first spray port 6a of the spray portion 6 as in the conventional case.

[0069] Therefore, even if the plating apparatus 100 increases the amount of plating solution sprayed from the spraying portion 6, shortens the time required for the object to be plated to pass through the plating forming portion 4 once, and increases the number of times the object to be plated circulates in the plating apparatus, the object to be plated will not rise excessively to a high position in the stored plating solution. Therefore, the plating apparatus 100 suppresses defects such as cracks, defects, and peeling of the plated film on the object to be plated caused by the object to be plated rising to a high position in the stored plating solution.

[0070] In the plating device 100, even if the amount of plating liquid sprayed from the spray section 6 is increased for the purpose of suppressing the deviation in the thickness of the plated film, the time required for the plated object to pass through the plating forming section 4 is shortened, and the number of times the plated object circulates in the plating device is increased, it is not easy to cause defects in the plated object.

[0071] (Usage Example of Plating Apparatus 100)

[0072] An example of a plating process using the plating apparatus 100 is described below.

[0073] First, a desired plating solution is put into the plating tank 1 .

[0074] Next, objects to be plated, dielectrics, and insulating balls of desired shapes, desired sizes, and desired numbers are introduced into the guide portion 13 in the plating tank 1. The order of introducing the plating solution and the objects to be plated, dielectrics, and insulating balls can be reversed. The introduced objects to be plated, dielectrics, and insulating balls are accumulated in the plating forming portion 4.

[0075] Next, the pump 10 is driven to eject the plating solution from the first ejection port 6a of the ejection portion 6. As a result, an upward flow of the plating solution is generated inside the metal pipe 2. Then, a portion of the objects to be plated, the dielectric, and the insulating balls accumulated in the plating forming portion 4 are taken out from the lower end of the plating forming portion 4 to the mixing portion 12, mixed with the ejected plating solution, and rise inside the metal pipe 2 along with the upward flow.

[0076] The object to be plated, the dielectric, and the insulating balls rising in the metal pipe 2 are ejected outward from the upper end of the metal pipe 2 and stirred.

[0077] The stirred object to be plated, dielectric, and insulating balls are deposited on the upper side of other objects to be plated, dielectric, and insulating balls that have already been deposited on the plating forming portion 4 .

[0078] A portion of the objects to be plated, dielectrics, and insulating balls accumulated in the plating forming section 4 is taken out from the lower end of the plating forming section 4 to the mixing section 12, whereby newly accumulated objects to be plated, dielectrics, and insulating balls gradually descend. In this way, the objects to be plated, dielectrics, and insulating balls circulate inside the plating device 100.

[0079] Next, the power source 15 is driven to apply a current between the metal pipe 2 as the first electrode and the second electrode 5. As a result, plating on the object to be plated is started in the plating forming portion 4.

[0080] When a plated film of a desired thickness is formed on the object to be plated after a given period of time, the power source 15 is stopped to stop plating the object to be plated. Next, the pump 10 is stopped to stop the circulation of the object to be plated, the medium, and the insulating balls in the plating apparatus 100.

[0081] The plating process is completed by taking out the object to be plated, the dielectric, and the insulating ball from the plating tank 1 and sorting the object to be plated.

[0082] (experiment)

[0083] In order to confirm the effectiveness of the present invention, the following experiments were conducted: Specifically, Example 1 was conducted using the plating apparatus of the present invention, and Comparative Examples 1 and 2 were conducted using plating apparatuses other than the plating apparatus of the present invention.

[0084] First, Example 1 was implemented. In Example 1, the plating device 100 of the above-mentioned embodiment was used. In the plating device 100 of Example 1, the first jet port 6a of the jet portion 6 was set to a circular shape with a diameter of 28 mm. In addition, in the plating device 100 of Example 1, the length of the plating forming portion 4 was set to 220 mm.

[0085] The first injection port 6a of the injection unit 6 of the plating apparatus 100 is provided with Figure 4 The mesh member 7 shown in (A) is a circle with a diameter of 28 mm, similarly to the first injection port 6a. The central portion 7c of the mesh member 7 is a circle with a diameter of 20 mm. The central portion 7c of the mesh member 7 is a double mesh structure in which the first mesh layer 7a with a mesh size of 900 μm and the second mesh layer 7b with a mesh size of 900 μm are overlapped. The peripheral portion 7d of the mesh member 7 is a single mesh structure including only the first mesh layer 7a with a mesh size of 900 μm.

[0086] A plating solution is contained in the plating tank 1 of the plating apparatus 100. As the plating solution, a Ni plating solution is used.

[0087] The object to be plated, the dielectric, and the insulating balls are put into the guide part 13 in the plating tank 1 of the plating device 100. The total amount of the object to be plated, the dielectric, and the insulating balls is set to 1720cc. Regarding the mixing ratio, the object to be plated is set to 1376cc (80 volume %), the dielectric is set to 86cc (5 volume %), and the insulating balls are set to 258cc (15 volume %).

[0088] The pump 10 is driven at a low output to eject the plating solution from the first ejection port 6a of the ejection unit 6, so that the object to be plated, the dielectric, and the insulating ball circulate in the order of the mixing unit 12, the hollow portion 2a of the metal pipe 2, the guide portion 13, the plating forming portion 4, and the mixing unit 12. The output of the pump 10 is gradually increased to increase the speed of the circulation of the object to be plated, the dielectric, and the insulating ball. Then, when the object to be plated that rises (sprays) relatively high in the stored plating solution among the objects to be plated discharged from the upper end of the hollow portion 2a of the metal pipe 2 reaches a given height, the increase in the output of the pump 10 is stopped and the output of the pump 10 is fixed. Specifically, when the object to be plated that rises relatively high in the stored plating solution among the objects to be plated discharged from the upper end of the hollow portion 2a of the metal pipe 2 reaches a height of 1 / 2 of the height between the upper end of the metal pipe 2 and the liquid level of the plating solution contained in the plating tank 1, the output of the pump 10 is fixed.

[0089] Next, the power source 15 is driven to apply a current between the metal pipe 2 as the first electrode and the second electrode 5 , and plating on the object to be plated is started in the plating forming portion 4 .

[0090] In this state, the amount of plating solution injected from the first injection port 6a of the injection unit 6 (the flow rate of the plating solution) was measured. In this state, the time required for each object to be plated to pass through the plating forming unit 4 once was measured.

[0091] In Example 1, the injection amount of the plating solution injected from the first injection port 6a of the injection portion 6 was 39 L / min. The time required for each object to be plated to pass through the plating forming portion 4 once was 10.8 seconds.

[0092] Next, Comparative Example 1 was implemented. In Comparative Example 1, a plating apparatus 1100 (not shown) in which a part of the plating apparatus 100 of Example 1 was modified was used.

[0093] The plating apparatus 1100 has a mesh member 17 (not shown) changed from the mesh member 7 of Example 1. Specifically, the mesh member 17 of Comparative Example 1 has a single mesh structure including one layer of a mesh with a mesh size of 900 μm over the entire surface.

[0094] In Comparative Example 1, under the same conditions as in Example 1, the plating solution was contained in the plating tank 1, and the object to be plated, the dielectric, and the insulating balls were placed into the guide portion 13 in the plating tank 1.

[0095] In Comparative Example 1, under the same conditions as in Example 1, the pump 10 was driven at a low output, and then the output of the pump 10 was gradually increased, and when the object to be plated that rose relatively high in the stored plating solution among the objects to be plated discharged from the upper end of the hollow portion 2a of the metal pipe 2 reached a height of 1 / 2 of the height between the upper end of the metal pipe 2 and the liquid level of the plating solution contained in the plating tank 1, the output of the pump 10 was fixed. Next, the power supply 15 was driven to apply a current between the metal pipe 2 as the first electrode and the second electrode 5, and plating on the object to be plated was started in the plating forming portion 4.

[0096] In Comparative Example 1, the amount of plating solution ejected from the first ejection port 6 a of the ejection portion 6 and the time required for each object to be plated to pass through the plating forming portion 4 once were measured in this state.

[0097] In Comparative Example 1, the injection amount of the plating liquid injected from the first injection port 6a of the injection unit 6 was 35 L / min. In Comparative Example 1, the time required for each object to be plated to pass through the plating forming unit 4 once was 18.4 seconds.

[0098] Next, Comparative Example 2 was implemented. In Comparative Example 2, a plating apparatus 1200 (not shown) in which a part of the plating apparatus 100 of Example 1 was modified was used.

[0099] The plating apparatus 1200 has a mesh member 27 (not shown) changed from the mesh member 7 of Example 1. Specifically, the mesh member 27 of Comparative Example 2 has a double mesh structure in which two layers of meshes with a mesh size of 900 μm are stacked on the entire surface.

[0100] In Comparative Example 2, under the same conditions as in Example 1 and Comparative Example 1, the plating solution was contained in plating tank 1, and an object to be plated, a dielectric, and insulating balls were introduced into guide portion 13 in plating tank 1.

[0101] In Comparative Example 1, under the same conditions as in Example 1 and Comparative Example 1, the pump 10 was driven at a low output, and then the output of the pump 10 was gradually increased, and when the object to be plated that rose relatively high in the stored plating solution among the objects to be plated discharged from the upper end of the hollow portion 2a of the metal pipe 2 reached a height of 1 / 2 of the height between the upper end of the metal pipe 2 and the liquid level of the plating solution contained in the plating tank 1, the output of the pump 10 was fixed. Next, the power supply 15 was driven to apply a current between the metal pipe 2 as the first electrode and the second electrode 5, and plating on the object to be plated was started in the plating forming portion 4.

[0102] In Comparative Example 1, the amount of plating solution ejected from the first ejection port 6 a of the ejection portion 6 and the time required for each object to be plated to pass through the plating forming portion 4 once were measured in this state.

[0103] In Comparative Example 2, the injection amount of the plating solution injected from the first injection port 6a of the injection unit 6 was 32 L / min. In Comparative Example 2, the time required for each object to be plated to pass through the plating forming unit 4 once was 11.2 seconds.

[0104] Table 1 shows the details of Example 1, Comparative Example 1, and Comparative Example 2, and the experimental results.

[0105] [Table 1]

[0106]

[0107] As can be seen from Table 1, the output of the pump 10 is set to be fixed (maintained) when the object to be plated that has risen relatively high in the stored plating solution among the objects to be plated discharged from the upper end of the hollow portion 2a of the metal pipe 2 reaches a height of 1 / 2 between the upper end of the metal pipe 2 and the liquid level of the plating solution contained in the plating tank 1. Under such conditions, compared with Comparative Examples 1 and 2, Example 1 has a larger flow rate of the plating solution and a shorter time required for the object to be plated to pass through the plating forming portion 4 once.

[0108] From the above, it can be seen that according to the present invention, while suppressing defects such as cracks, defects, and peeling of the plating film in the plated object, the flow rate of the plating solution can be increased and the time required for the plated object to pass through the plating forming portion 4 once can be shortened, compared with the structure in which the screen member is a single screen on the entire surface (Comparison Example 1) and the structure in which the screen member is a double screen on the entire surface (Comparison Example 2).

[0109] According to the present invention, the flow rate of the plating solution can be increased while suppressing the occurrence of defects in the object to be plated, and the number of times the object to be plated circulates in the plating apparatus can be increased, thereby suppressing the thickness variation of the formed plated film.

[0110] The plating apparatus according to the embodiment has been described above. However, the present invention is not limited to the above-described contents, and various modifications can be made according to the gist of the invention.

[0111] For example, in the above-mentioned embodiment, the central portion 7c of the mesh member 7 is set to a double mesh structure, and the peripheral portion 7d of the mesh member 7 is set to a single mesh structure, but the present invention is not limited to this structure. For example, in the central portion 7c of the mesh member 7, when it is desired to further suppress the amount of plating solution passing through, the central portion 7c may be set to a triple mesh structure, or a quadruple mesh structure, or a more multiple mesh structure.

[0112] In addition, when viewed in the plane direction, the screen member 7 does not need to be composed of only the central portion 7c and the peripheral portion 7d. For example, an intermediate portion may be provided between the central portion 7c and the peripheral portion 7d. Furthermore, for example, the central portion 7c may be provided with a triple screen structure, the intermediate portion may be provided with a double screen structure, and the peripheral portion 7d may be provided with a single screen structure.

[0113] A plating apparatus according to an embodiment of the present invention is as described in the column of “Solution to Problem”.

[0114] In the plating device, a cylindrical metal pipe having a hollow portion is preferably provided directly above the ejection unit. In this case, the flow of the plating solution that rises rapidly in the center portion of the metal pipe can be suppressed (decelerated).

[0115] Furthermore, it is also preferable that the number of layers of the mesh in the peripheral portion is 1, and the number of layers of the mesh in the central portion is 2. In this case, the mesh member can be easily manufactured.

[0116] It is also preferred that the mesh size of the central portion of the mesh member is smaller than that of the peripheral portion when viewed in the planar direction. In this case, the amount of plating solution passing through the central portion of the mesh member can be suppressed compared to the amount of plating solution passing through the peripheral portion.

[0117] It is also preferred that the central portion is circular when viewed in the planar direction. In this case, the mesh member can uniformly allow the plating solution to pass therethrough in all radial directions from the center of the mesh member.

[0118] It is also preferred that the central portion is a polygon when viewed in the plane direction. In particular, it is also preferred that the central portion is a quadrilateral when viewed in the plane direction. In this case, the screen member can be easily manufactured.

[0119] It is also preferred that the ejection portion is an inner cylindrical shape having a bottom surface and an inner wall and having a first ejection port disposed at an upper end, a second ejection port disposed at the bottom surface, an opening area of ​​the second ejection port being smaller than an opening area of ​​the first ejection port, and the plating liquid is ejected into the ejection portion from the second ejection port. In this case, the diameter of the first ejection port from which the plating liquid is ejected from the ejection portion to the plating tank can be increased compared to the diameter of the pipe connected to the second ejection port, and the speed of the plating liquid ejected from the first ejection port can be homogenized (the difference between the fast part and the slow part is reduced) while passing through the ejection portion.

[0120] It is also preferred to include: a cylindrical metal tube, which is the first electrode and has a hollow portion; a partition tube, which is made of an insulating material, is cylindrical with a hollow portion, and is formed with a plurality of holes that allow the plating solution to pass but does not allow the plated object to pass; and a second electrode, wherein the metal tube, the partition tube, and the second electrode are respectively accommodated in a plating tank, the metal tube is arranged in the hollow portion of the partition tube, a plating forming portion is formed between the inner side of the partition tube and the outer side of the metal tube, the second electrode is arranged on the outer side of the partition tube, and the injection portion is provided below the metal tube, the plated object rises in the hollow portion of the metal tube along with the rising flow of the plating solution injected by the injection portion, is discharged outwardly from the upper end of the hollow portion of the metal tube, is stirred in the plating solution, and then descends in the plating forming portion, and is plated by applying a current between the metal tube, which is the first electrode, and the second electrode during the descent. In this case, the speed of the plating solution rising inside the metal pipe can be controlled, and in particular, the flow of the plating solution rising fast in the center of the metal pipe can be suppressed (slowed down). In addition, the first electrode is, for example, a cathode electrode, and the second electrode is, for example, an anode electrode.

[0121] Description of Reference Numerals

[0122] 1···plating tank;

[0123] 2···metal tube (first electrode; cathode);

[0124] 2a···hollow part;

[0125] 2b···supporting portion;

[0126] 3···septum tube;

[0127] 3a···hollow part;

[0128] 3b···hole;

[0129] 4···plating forming portion;

[0130] 5···2nd electrode (anode);

[0131] 6···jet unit;

[0132] 6a···1st injection port;

[0133] 6b···the second injection port;

[0134] 7···Screen member;

[0135] 7a···1st screen layer;

[0136] 7b···the second screen layer;

[0137] 7c···Central part;

[0138] 7d···peripheral department;

[0139] 8···Circular line;

[0140] 9···Liquid suction port;

[0141] 10···Pump;

[0142] 11···Filter;

[0143] 12···Mixing Department;

[0144] 13···guiding department;

[0145] 14···Reflector (deflector);

[0146] 14a···Suppression plate;

[0147] 15···Power supply.

Claims

1. A plating device comprising: a plating tank storing a plating solution containing an object to be plated; and a jetting portion formed in the plating tank and having a first jetting port for jetting the plating solution; The plating solution ejected from the ejection unit agitates the object to be plated contained in the plating solution. in, The first injection port of the injection portion is provided with a mesh member, The screen member is formed by overlapping at least two screens. The screen member has a central portion and a peripheral portion provided outside the central portion when viewed in a planar direction. The peripheral portion is formed by one layer of the mesh or a plurality of layers of the mesh, The central portion is formed by a plurality of layers of the mesh, The number of layers of the mesh in the central portion is greater than the number of layers of the mesh in the peripheral portion.

2. The plating device according to claim 1, wherein: A cylindrical metal pipe having a hollow portion is provided directly above the injection portion.

3. The plating device according to claim 1 or 2, wherein: The number of layers of the screen in the peripheral portion is 1, The number of layers of the mesh in the central portion is two.

4. The plating device according to any one of claims 1 to 3, wherein: When the mesh member is viewed in a planar direction, a mesh size of the central portion is smaller than a mesh size of the peripheral portion.

5. The plating device according to any one of claims 1 to 4, wherein: When viewed in a planar direction, the central portion is circular.

6. The plating device according to any one of claims 1 to 4, wherein: When viewed in a planar direction, the central portion is a polygon.

7. The plating device according to claim 6, wherein: When viewed in a planar direction, the central portion is a quadrilateral.

8. The plating device according to any one of claims 1 to 7, wherein: The injection portion is in the shape of an inner cylinder having a bottom surface and an inner wall and provided with the first injection port at the upper end. A second injection port is provided on the bottom surface, The opening area of ​​the second injection port is smaller than the opening area of ​​the first injection port. The plating liquid is ejected from the second ejection port toward the ejection portion.

9. The plating device according to any one of claims 1 to 8, wherein: The plating device comprises: The cylindrical metal tube is the first electrode and has a hollow portion; The partition tube is made of an insulating material, is in the shape of a tube with a hollow portion, and is formed with a plurality of holes through which the plating solution passes but the plated object does not pass; and The second electrode, The metal tube, the partition tube, and the second electrode are respectively accommodated in the plating tank. The metal tube is arranged in the hollow portion of the partition tube, and a plating forming portion is formed between the inner side of the partition tube and the outer side of the metal tube. The second electrode is arranged outside the partition tube, The injection unit is arranged below the metal pipe. The object to be plated rises in the hollow portion of the metal tube along with the rising flow of the plating solution sprayed by the spray portion, and is discharged outward from the upper end of the hollow portion of the metal tube. After being stirred in the plating solution, the object descends in the plating forming portion, and during the descent, the object is plated by applying an electric current between the metal tube serving as the first electrode and the second electrode.

10. The plating device according to claim 9, wherein: The first electrode is a cathode electrode, The second electrode is an anode electrode.

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