JP5092240B2 - Plating equipment - Google Patents

Description

  The present invention relates to a plating apparatus, and more particularly to a plating apparatus used in a so-called barrel plating method in which a barrel containing a workpiece is immersed in a plating solution and plating is performed while rotating the barrel.

  One of the plating methods used when plating small-sized workpieces such as electronic components is to be plated while rotating the barrel while the barrel is immersed in a plating solution. There is a barrel plating method. FIG. 7 is a diagram showing an example of a configuration of a conventional barrel plating apparatus used when plating an electronic component.

  This rotary barrel plating apparatus is composed of a net-like member at least partially passing a plating solution 54, and in a barrel 51 in which a cathode electrode (feeding terminal) 52 is disposed, a large number of, for example, multilayer ceramic capacitors are provided. After introducing an object to be plated (not shown) and a contact medium (not shown) such as a steel ball for conducting the object to be plated and the cathode electrode 52, the barrel 51 is placed in the plating bath 53. 54, the barrel 51 is rotated in the plating solution 54 while energizing between the anode electrode 55 and the cathode electrode 52 disposed in the plating tank 53, and the object to be plated is passed through the contact medium. Then, the object to be plated is plated by bringing it into contact with the cathode electrode 52 and the plating solution 54, for example, Ni plating or Sn plating is performed on the external electrode of the multilayer ceramic capacitor. It is configured.

  However, in such a barrel plating method, as in the case of other plating methods, foreign matter accumulates at the bottom of the plating tank, which floats by stirring and flowing of the plating solution and adheres to the surface of the object to be plated. As a result, there is a problem that defective plating occurs or the uniformity of the plating film is impaired.

  Therefore, for example, as shown in FIG. 8, by dividing a plating tank 61 into which the plating solution 54 is placed by a partition plate 62, the upper tank portion that becomes a region in which the plating object 60 is immersed in the plating solution 54. 63 and the lower tank part 64 below the upper tank part 63 and the side walls 63a and 64a on one side of the lower tank part 64 are provided with plating solution inlets 73a and 74a, respectively. The plating solution discharge port 74b is provided in the other side wall 64b opposite to the one side wall 64a, the liquid flow pump 76 is provided in the circulation line 75, and the plating solution is circulated. There has been proposed a plating apparatus provided with a filtering means 77 to filter deposits (see Patent Document 1).

However, when the configuration of the plating apparatus (FIG. 8) of Patent Document 1 is applied to the barrel plating method as described above, as shown in FIG. 9, the plating tank 61 is supplied from the plating solution inlet 73 a of the upper tank portion 63. Due to the flow of the plating solution 54 flowing in, the workpiece 71 rises in the barrel 51, and the plating current is supplied from the cathode electrode 52 to the workpiece 71 via the contact medium (not shown). There is a problem that it becomes insufficient and causes insufficient plating, that is, a defect that the plating film thickness becomes too thin or no plating film is formed at all.
In particular, when the flow of the plating solution 54 is directed from below to the barrel 51, the degree of the so-called plating object in the barrel 51 tends to increase.

That is, according to the barrel plating method, the object to be plated rolls by the rotation of the barrel, and the degree of contact with the cathode electrode and the contact medium decreases, but due to the flow of the plating solution flowing out from the plating solution inlet. There is a problem in that the degree of soaring of the object to be plated is further increased, the supply of the plating current to the object to be plated is further reduced, and insufficient plating is caused.
JP 2003-221698 A

  The invention of the present application solves the above-mentioned problem, while preventing the occurrence of poor plating due to the plating object in the barrel rising, sufficiently agitating the plating solution in the plating tank to eliminate the accumulation of foreign matters, It aims at providing the plating apparatus which can perform favorable barrel plating.

In order to solve the above problems, the plating apparatus according to claim 1 comprises:
The tube is configured to be rotatable and includes a cathode electrode for supplying power to the object to be plated, and at least a part of the peripheral wall portion is made of a material that allows the plating solution to pass through without passing the object to be plated. Barrel,
When plating an object to be plated accommodated in the barrel, a plating tank for accommodating a plating solution in which the barrel is immersed,
A suction port that is located outside the barrel and sucks the plating solution in the plating tank, and a plating solution that is located outside the barrel and sucked from the suction port is jetted to the plating tank through a circulation line. A circulation means for circulating the plating solution in the plating tank,
It is formed using a plate-like material that does not allow the plating solution to pass, and is disposed in a region between the jet port and the barrel in the plating tank so that at least a part thereof faces the jet port. And a buffer member for preventing the flow of the plating solution ejected from the above from affecting the movement of the object to be plated in the barrel.

Moreover, the plating apparatus of Claim 2 is arrange | positioned in the aspect which surrounds the said barrel when the said buffer member planarly views .

The plating apparatus according to claim 1 is configured to be cylindrical and rotatable, includes a cathode electrode for supplying power to the object to be plated, and at least a part of the peripheral wall portion does not allow the object to be plated to pass therethrough. A barrel formed of a material that passes through, a plating tank that contains a plating solution in which the barrel is immersed when plating an object to be plated accommodated in the barrel, and located outside the barrel and in the plating tank The plating solution in the plating tank is circulated with a suction port that sucks in the plating solution and a jet port that is located outside the barrel and jets the plating solution sucked from the suction port through the circulation line to the plating tank. Is formed using a plate-like material that does not allow the plating solution to pass therethrough, and is disposed in a region between the jet port and the barrel in the plating tank so that at least a part faces the jet port. And from the spout Since the flow of the plating solution is provided with a buffer member for preventing the movement of the object to be plated in the barrel, the function of the buffer member allows the object to be plated in the barrel to It is possible to suppress soaring due to the influence of the flow of the plating solution ejected from the ejection port, while preventing the current supplied to the object to be plated from the cathode electrode via the contact medium from being reduced, It is possible to sufficiently stir the plating solution in the plating tank to eliminate the accumulation of foreign matters and perform good barrel plating.
Moreover, since the buffer member is arranged in the region between the jet port and the barrel in the plating tank, it is possible to suppress the increase in size of the equipment.

Further, a cushioning member, because formed using a plate material that does not pass through the plating solution, preventing the flow of the plating solution jetted from the jetting port, reliably to or soaring is the object to be plated in the barrel It becomes possible to prevent.

Further, when the buffer member is arranged in such a manner as to surround the barrel when viewed in plan as in the plating apparatus of claim 2, the flow of the plating solution ejected from the ejection port It is possible to more reliably prevent adverse effects on the movement of the object to be plated, and the present invention can be more effectively realized.

  The features of the present invention will be described in more detail below with reference to examples of the present invention.

FIG. 1 is a view showing a configuration of a plating apparatus according to an embodiment (Example 1) of the present invention, in which (a) is a front sectional view and (b) is a side sectional view.
The plating apparatus of Example 1 is (a) configured to be cylindrical and rotatable, includes a cathode electrode 11 for supplying power to the object to be plated 1, and at least a part of the peripheral wall portion 2 a is to be plated. A barrel 2 made of a material that allows the plating solution 3 to pass through without passing through 1; and (b) the object to be plated 1, the object to be plated 1 and the cathode electrode 11 are electrically connected, for example, a contact medium such as a steel ball 13, a plating tank 4 containing a plating solution 3 in which the barrel 2 is immersed, a suction port 5 for sucking the plating solution 3 in the plating bath 4, and a plating solution sucked from the suction port 5. 3, a circulation means 8 for circulating the plating solution 3 in the plating tank 4, provided with a spout 7 for jetting into the plating tank 4 through the circulation line 6, and (c) disposed in the plating tank 4. Flow of plating solution 3 installed and ejected from ejection port 7 And a buffer member 9 for preventing the influence on the movement of the object to be plated 1 in the barrel 2.

  Further, in this plating apparatus, the cathode line 10 is inserted into the barrel 2 from both end faces 2 b of the barrel 2, and the cathode electrode 11 is disposed at the tip of the cathode line 10. A pair of anode electrodes 12 is disposed in the plating tank 4 so as to sandwich the barrel 2.

In the plating apparatus of the first embodiment, the suction port 5 is disposed below the one side surface 4 a of the plating tank 4, and the jet port 7 is a side surface facing the side surface 4 a of the plating tank 4 in which the suction port 5 is disposed. It is arranged at the lower part of 4b.
Further, the circulation line 6 is provided with a filtering means 14, which removes foreign matter by filtering the plating solution 3 sucked from the plating tank 4 through the suction port 5, and the concentration of the foreign matter in the plating solution 3. It is comprised so that a raise of can be suppressed.

  In the plating apparatus of Example 1, the buffer member 9 is made of a heat-resistant vinyl chloride, is not formed with a through hole, and is formed using a plate-like material that does not allow the plating solution 3 to pass through. Yes. Further, the buffer member 9 is disposed so as to block between the ejection port 7 and the suction port 5, and the flow of the plating solution 3 ejected from the ejection port 7 hardly reaches the barrel 2 directly, The object to be plated 1 in the barrel 2 is prevented from flying up, and the supply of current from the cathode electrode 11 to the object to be plated 1 via the contact medium 13 can be prevented from being reduced. ing.

  In the plating apparatus configured as described above, the buffer member functions to suppress the object to be plated 1 in the barrel 2 from rising due to the influence of the flow of the plating solution 3 ejected from the ejection port. It is possible to prevent the object to be plated 1 in the barrel 2 from rising and reducing the supply of current from the cathode electrode 11 to the object to be plated 1 via the contact medium 13. That is, in the case of the configuration of the first embodiment, the buffer member 9 is disposed so as to block between the jet port 7 and the suction port 5 and reaches the lower side than the jet port 7. It is possible to prevent the liquid flow from moving from below to the barrel 2, and it is possible to reliably suppress and prevent the rising of the workpiece 1 in the barrel 2. As a result, the plating solution in the plating tank 4 is sufficiently agitated to prevent foreign matter from being deposited while preventing the so-called plating shortage defect that the plating film thickness is too thin or no plating film is formed at all. This makes it possible to perform good barrel plating.

  In addition, when forming the buffer member 9 using the material which does not allow the plating solution 3 to pass, the area | region where the barrel 1 is immersed in the plating tank 4 so that the plating solution 3 in the barrel 2 may be updated. It is necessary to prevent the other area from being completely partitioned by the buffer member 9.

2A and 2B are diagrams showing a plating apparatus according to an embodiment (Example 2) of the invention to which the present invention relates, wherein FIG. 2A is a front sectional view, and FIG. 2B is a plan view of a main part.
The plating apparatus includes a buffer member 19 formed using a mesh material that allows the plating solution 3 to pass through. The buffer member 19 has an L-shaped structure including a vertical portion 19a and a horizontal portion 19b. Have.

In addition, as a mesh material which comprises the buffer member 19, for example, an insulating mesh having a wire diameter of 0.05 mm and an opening of 0.12 mm (150 mesh) is used as a suitable material.
Other configurations of the plating apparatus of the second embodiment are the same as those of the above-described plating apparatus of the first embodiment. In FIGS. 2A and 2B showing the plating apparatus of Example 2, the anode electrode is not shown.

  Even in the case of using a mesh material as the buffer member 19 as in the case of the second embodiment, the buffer member 19 is barreled by the influence of the flow of the plating solution 3 ejected from the ejection port 7. In order to perform the function of suppressing the object to be plated 1 in 2 from rising, the object to be plated 1 in the barrel 2 rises, and the current flowing from the cathode electrode 11 to the object 1 through the contact medium 13 is increased. It is possible to prevent the supply from being reduced. As a result, the plating solution in the plating tank is sufficiently agitated to prevent foreign matter from depositing while preventing the so-called plating shortage failure that the plating film thickness is too thin or no plating film is formed at all. And good barrel plating can be performed.

  In addition, in this Example 2, although the buffer member 19 formed using the mesh material is used, for example, a buffer member using a plate-like material having many through holes (small holes) such as punching metal is provided. Even in the case of the configuration described above, the same effects as those of the plating apparatus of Example 2 can be obtained.

  Moreover, when using the plate-shaped material which has a through-hole for a buffer member, in order not to transmit the flow of a plating solution to a barrel, it is preferable that the opening rate of a buffer member does not become so high. The same applies to the case of using a mesh material.

[Plating test]
The plating apparatus of Example 1 provided with the buffer member 9 formed using a plate-shaped material, and the plating apparatus of Example 2 of the invention to which the present invention relates, including the buffer member 19 formed using a mesh material. Then, using a multilayer ceramic capacitor with a width W of 0.3 mm, a length L of 0.6 mm, and a thickness T of 0.3 mm as the object 1 to be plated, Ni plating is applied to the surface of the external electrode, resulting in insufficient plating failure. The rate was examined.

  For comparison, plating was performed under the same conditions using a plating apparatus (comparative example) that does not include a buffer member, and the occurrence rate of insufficient plating defects was examined.

  Table 1 shows the incidence of insufficient plating defects when plating is performed using the plating apparatuses of Examples 1 and 2 and the comparative example.

  As shown in Table 1, it was confirmed that when a plating apparatus of a comparative example that does not include a buffer member was used, it increased to 100 ppm when the occurrence rate of insufficient plating defects was large.

On the other hand, when the plating apparatus according to Example 2 which is Example 1 of the present invention and the invention to which the present invention relates is used, it was confirmed that the occurrence rate of insufficient plating failure is 10 ppm or less.

  Moreover, the case where the plating apparatus of Example 1 provided with the buffer member 9 formed using the plate-shaped material and the plating apparatus of Example 2 provided with the buffer member 19 formed using the mesh material were used. When compared with the case, it was confirmed that the incidence of insufficient plating defects was lower when the plating apparatus of Example 1 including the buffer member 9 formed using a plate-like material was used. This is because the buffer member 9 formed using the plate material completely blocks the flow of the plating solution, whereas the buffer member 19 formed using the mesh material allows a certain amount of the plating solution to pass. It is thought to do.

  However, when using a buffer member made of a material capable of circulating a plating solution, such as a buffer member using a plate-like member having a through hole or a mesh-like buffer member, the entire barrel should be covered. A buffer member can be provided, and a plating apparatus capable of performing stable barrel plating can be configured.

[Modification]
In the plating apparatus of the present invention, various applications and modifications can be made with respect to the structure and constituent materials of the buffer member.
Hereinafter, various modifications of the plating apparatus of the present invention will be described.

<Modification 1>
FIGS. 3A and 3B are diagrams showing a configuration of a plating apparatus according to Modification 1 of the present invention, in which FIG. 3A is a front sectional view and FIG. 3B is a plan view of a main part.
In the plating apparatus of Modification 1, a plate-like material made of heat-resistant vinyl chloride and having no through holes is used as the buffer member 9.

  Further, the buffer member 9 has an L-shaped structure including a vertical portion 9a and a horizontal portion 9b, and the plating solution 3 ejected from the ejection port 7 does not directly hit the lower surface of the barrel 2, It arrange | positions so that between the jet nozzle 7 and the suction inlet 5 may be interrupted | blocked by the buffer member 9. FIG. Other configurations are the same as those of the plating apparatus of the first embodiment.

  In this plating apparatus, the L-shaped buffer member 9 sufficiently functions to suppress the object to be plated 1 in the barrel 2 from rising due to the influence of the flow of the plating solution 3 ejected from the ejection port 7. Therefore, it is possible to prevent the supply of current from the cathode electrode 11 to the workpiece 1 via the contact medium 13 from being reduced. As a result, the plating solution 3 in the plating tank 4 is sufficiently stirred to prevent the occurrence of foreign matters while preventing the so-called plating deficiency defect that the plating film thickness is too thin or no plating film is formed at all. Deposition is eliminated and good barrel plating can be performed.

<Modification 2>
4A and 4B are diagrams showing a configuration of a plating apparatus according to Modification 2 of the present invention, in which FIG. 4A is a front sectional view, and FIG. 4B is a plan view of a main part.
In the plating apparatus of Modification 2, a plate-like material made of heat-resistant vinyl chloride and having no through-holes is used as the buffer member 9.

  The shock-absorbing member 9 includes four side walls 9c, 9d, 9e, and 9f, and has a structure that surrounds the barrel 2 when viewed from above in a plan view with a planar shape having an open top and bottom surface. In view of the positional relationship with the spout 7 so that the plating solution 3 spouted from the spout 7 does not directly hit the lower surface of the barrel 2, the space between the spout 7 and the suction port 5 is buffered. It is configured to be blocked by the member 9. Other configurations are the same as those of the plating apparatus of the first embodiment.

  Also in this plating apparatus, the frame-shaped buffer member 9 sufficiently functions to suppress the plating object 1 in the barrel 2 from rising due to the influence of the flow of the plating solution 3 ejected from the ejection port 7. It is possible to prevent the supply of current from the cathode electrode 11 to the workpiece 1 through the contact medium 13 from being reduced. As a result, the plating solution in the plating tank is sufficiently agitated to prevent foreign matter from depositing while preventing the so-called plating shortage failure that the plating film thickness is too thin or no plating film is formed at all. And good barrel plating can be performed.

<Modification 3>
5A and 5B are diagrams showing a configuration of a plating apparatus according to Modification 3 of the present invention, in which FIG. 5A is a front cross-sectional view, and FIG. 5B is a plan view of a main part.
In the plating apparatus of Modification 3, a plate-like material made of heat-resistant vinyl chloride and having no through-holes is used as the buffer member 9.

  Further, the buffer member 9 has a bottom-like structure including a pair of substantially vertical side wall portions 9g and 9h and a bottom portion 9i that is bent at an obtuse angle so that the center is a valley-folded bent portion. It is arranged in consideration of the positional relationship with the spout 7 so that the plating solution spouted from the spout 7 does not directly hit the lower surface of the barrel 2, and the space between the spout 7 and the suction opening 5 is It is configured to be blocked by the buffer member 9. Other configurations are the same as those of the plating apparatus of the first embodiment.

  Also in this plating apparatus, the buffer member 9 having a shape that is bent at an obtuse angle so that the center is a bent portion of the valley fold is applied to the inside of the barrel 2 due to the influence of the flow of the plating solution 3 ejected from the ejection port 7. In order to sufficiently perform the function of suppressing the plating object 1 from flying up, it is possible to prevent the supply of current from the cathode electrode 11 to the object to be plated 1 via the contact medium 13 from being reduced. As a result, the plating solution in the plating tank is sufficiently agitated to prevent foreign matter from depositing while preventing the so-called plating shortage failure that the plating film thickness is too thin or no plating film is formed at all. And good barrel plating can be performed.

<Modification 4>
6A and 6B are diagrams showing a configuration of a plating apparatus according to Modification 4 of the invention to which the present invention relates, wherein FIG. 6A is a front sectional view, and FIG. 6B is a plan view of the main part.
In the plating apparatus of Modification 4, a buffer member 19 formed using a polyethylene mesh material is used.

  Further, the buffer member 19 has a box-like structure having a rectangular parallelepiped shape in which only the upper surface is an open surface, and the barrel 2 is accommodated in the box-shaped buffer member 19, that is, the barrel 2. The portion excluding the upper surface side is disposed so as to be covered with the buffer member 19, and the plating solution 3 ejected from the ejection port 7 does not directly hit the lower surface side of the barrel 2. .

In addition, in the plating apparatus of this modification 4, since the mesh material which allows the plating solution 3 to pass through is used as the buffer member 19, the buffer member 19 is configured so as to cover the entire barrel 2. However, since the plating solution 3 around the barrel inside the box-shaped buffer member 19 is replaced with the plating solution 3 outside the box-shaped buffer member 19, the plating is not hindered.
Other configurations are the same as those of the plating apparatus of the first embodiment.

  Also in the case of the configuration of the modified example 4, the box-shaped buffer member 19 has a function of suppressing the plating object 1 in the barrel 2 from rising due to the influence of the flow of the plating solution 3 ejected from the ejection port 7. Therefore, it is possible to prevent the supply of current from the cathode electrode 11 to the workpiece 1 through the contact medium 13 from being reduced. As a result, the plating solution in the plating tank is sufficiently agitated to prevent foreign matter from depositing while preventing the so-called plating shortage failure that the plating film thickness is too thin or no plating film is formed at all. And good barrel plating can be performed.

  The invention of the present application is not limited to the above-described embodiments and modifications, but the specific shape and configuration of the barrel, the arrangement of the cathode electrode provided in the barrel, the specific structure of the plating tank, and the suction port In the scope of the invention, various applications and modifications may be made within the scope of the invention regarding the specific configuration of the plating solution circulation means provided with the spout, the circulation line, the type and composition of the plating solution, the type of the object to be plated, etc. Is possible.

As described above, according to the present invention, the plating solution in the plating tank is sufficiently removed while preventing the so-called plating shortage failure that the plating film thickness is too thin or no plating film is formed at all. It is possible to perform good barrel plating by eliminating the accumulation of foreign matters by stirring.
Therefore, the present invention can be widely applied to the field of manufacturing technology of electronic parts such as a multilayer ceramic capacitor provided with an external electrode that needs to be plated.

It is a figure which shows the structure of the plating apparatus concerning one Example (Example 1) of this invention, (a) is front sectional drawing, (b) is side sectional drawing. It is a figure which shows the structure of the plating apparatus concerning the Example (Example 2) of the invention with which this invention relates, (a) is front sectional drawing, (b) is a top view of the principal part. It is a figure which shows the plating apparatus concerning the modification 1 of this invention, (a) is front sectional drawing, (b) is a top view of the principal part. It is a figure which shows the structure of the plating apparatus concerning the modification 2 of this invention, (a) is front sectional drawing, (b) is a top view of the principal part. It is a figure which shows the structure of the plating apparatus concerning the modification 3 of this invention, (a) is front sectional drawing, (b) is a top view of the principal part. It is a figure which shows the structure of the plating apparatus of the modification 4 concerning the invention with which this invention relates, (a) is front sectional drawing, (b) is a top view of the principal part. It is a figure which shows an example of a structure of the conventional barrel plating apparatus used when plating an electronic component. It is a figure which shows the other example of the conventional plating apparatus. In the conventional plating apparatus, it is a figure which shows typically the state which a to-be-plated object soars in a barrel with the flow of the plating solution which flows in into a plating tank from a plating solution inflow port.

DESCRIPTION OF SYMBOLS 1 To-be-plated object 2 Barrel 2a Perimeter wall part 2b End surface 3 Plating liquid 4 Plating tank 4a, 4b Side surface of a plating tank 5 Suction port 6 Circulation line 7 Spout 8 Circulation means 9 Buffer member 9a Vertical part 9b Horizontal part 9c, 9d, 9e 9f Side wall portion 9g, 9h A pair of side wall portions 9i Bottom portion 10 Cathode line 11 Cathode electrode 12 Anode electrode 13 Contact medium 14 Filtering means 19 Buffer member 19a Vertical portion 19b Horizontal portion

Claims (2)

The tube is configured to be rotatable and includes a cathode electrode for supplying power to the object to be plated, and at least a part of the peripheral wall portion is made of a material that allows the plating solution to pass through without passing the object to be plated. Barrel,
When plating an object to be plated accommodated in the barrel, a plating tank for accommodating a plating solution in which the barrel is immersed,
A suction port that is located outside the barrel and sucks the plating solution in the plating tank, and a plating solution that is located outside the barrel and sucked from the suction port is jetted to the plating tank through a circulation line. A circulation means for circulating the plating solution in the plating tank,
It is formed using a plate-like material that does not allow the plating solution to pass, and is disposed in a region between the jet port and the barrel in the plating tank so that at least a part thereof faces the jet port. And a buffer member for preventing the flow of the plating solution ejected from the above from affecting the movement of the object to be plated in the barrel. The plating apparatus according to claim 1, wherein the buffer member is disposed in such a manner as to surround the barrel when viewed in plan .

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