JP3891580B2 - Barrel plating method - Google Patents

Description

The present invention relates to a barrel plating method for performing plating end electrode portion of the small chip components.

  In the conventional parallel barrel with the horizontal rotation axis as the center of rotation, the size of the chip part is large and the mesh size in the barrel corresponding to it is large. It was possible to cope with the problem by extending the barrel charging time into the tank or by vibrating or swinging the barrel.

  In recent years, however, chip parts have been further miniaturized, and the mesh size has become finer. Accordingly, it has been difficult to vent the gas in the barrel by the conventional method. In addition, hydrogen gas generated during plating also has a problem of being accumulated in the barrel without coming off.

  If there is a problem of gas accumulation in the barrel as described above, “no plating” defect due to product floating in the barrel after the barrel is put into the plating tank, or the amount of ions in the barrel is unstable As a result, the plating quality itself is adversely affected.

  Conventionally, the following Patent Document 1 has been proposed as focusing on the problem of gas generation in the barrel.

In Japanese Patent Laid-Open No. 2003-73897, the processing liquid (plating liquid) outside the barrel is sucked by a pump and sucked by the pump from a discharge pipe penetrating the barrel to a position higher than the liquid level in the inner space of the barrel. The treatment liquid outside the barrel is discharged. That is, the gas in the barrel is discharged by increasing the liquid level in the barrel internal space.

  This patent document 1 is based on the premise that the barrel is partially immersed in the processing liquid, and is not applicable when the entire barrel is immersed in the processing liquid for plating. In the case of Patent Document 1, a pump is required for each barrel unit that rotatably holds a barrel, and a discharge pipe is provided through the barrel, so that the structure is complicated.

In view of the above points, the present invention is characterized by the occurrence of "no plating" defect due to the product floating in the barrel after the barrel is put into the plating tank, and the ion quantity in the barrel becomes unstable, resulting in plating quality. It is an object of the present invention to provide a barrel plating method capable of effectively removing the occurrence of a gas accumulation in the barrel which causes an influence on itself.

  Other objects and novel features of the present invention will be clarified in embodiments described later.

In order to achieve the above object, the invention of claim 1 of the present application uses a barrel that allows a plating solution to pass through but does not allow an object to be plated to pass through, accommodates the object to be plated in the barrel, and places the barrel in the plating solution. In the barrel plating method in which the object to be plated is electroplated by immersing in
A pump and a suction nozzle sucked by the pump are arranged outside the barrel, and the one end of the barrel is inclined so as to be higher, and the gas in the barrel collected in the inner space on the higher side of the barrel is sucked into the suction. It is characterized by sucking with a nozzle.

  The barrel plating method according to the second aspect of the present invention is the barrel plating method according to the first aspect, wherein the barrel has a cylindrical portion and end surface portions located on both sides of the cylindrical portion, and one end surface portion has a suction opening hole. Is formed, and the gas in the barrel is sucked in a state where the suction nozzle is closely opposed to or inserted in the suction opening hole.

  According to the present invention, the suction nozzle sucked by the pump is arranged outside the barrel, and the one end of the barrel is inclined so as to be high, and the gas in the barrel gathered in the internal space on the high side of the barrel, It is the structure which attracts | sucks with the said suction nozzle and generation | occurrence | production of the gas pool in a barrel can be removed effectively. For this reason, it is possible to solve the problem of “no plating” defect due to the product floating in the barrel after the barrel is put into the plating tank, and the problem that the ion amount in the barrel becomes unstable and adversely affects the plating quality.

  Further, since the pump and the suction nozzle are provided outside the barrel, the barrel structure is not complicated.

Hereinafter, as the best mode for carrying out the present invention, an embodiment of a barrel plating method will be described with reference to the drawings.

  1 to 4, reference numeral 1 denotes a barrel unit, and a barrel 10 is rotatably held by a support frame 2. The barrel 10 includes a cylindrical portion 11, end surface portions 12 and 13 located on both sides thereof, and shaft bodies 15 and 16 provided at outer center positions of both end surface portions 12 and 13. 15 and 16 are pivotally supported by the support frame 2. A barrel rotation drive motor M is attached to the upper portion of the support frame 2, and the rotation drive force is transmitted to the shaft body 16 that is the rotation drive shaft of the barrel 10 via the rotation drive transmission mechanism 4. Yes.

  As shown in FIGS. 2 and 3, the cylindrical portion 11 of the barrel 10 has a polygonal cylindrical shape such as an octagonal cylindrical shape, and a large number of through holes 20 are formed. The end surface portions 12 and 13 are located on both sides of the tubular portion 11 and close the opening of the tubular portion. However, a gas in a barrel described later is placed outside the barrel at a position near the outer edge of one end surface portion 12. Suction opening holes 21 for more suction are formed at equiangular intervals. In particular, when the cylindrical portion 11 is a polygonal cylindrical shape, the suction opening hole 21 is disposed in the vicinity of the corner portion. Further, the barrel 10 has a mesh member 17 on the inner wall surface so as to allow the plating solution to pass but not the object to be plated. That is, a mesh member 17 is stretched along the inner surfaces of the cylindrical portion 11 and the end surface portions 12 and 13 so as to allow the plating solution to pass therethrough but not the object 30 (small chip parts or the like). Therefore, the small holes 20 and the suction opening holes 21 can be set sufficiently larger than the object to be plated 30.

  The cylindrical portion 11, the end surface portions 12 and 13, and the mesh member 17 of the barrel 10 are non-conductive members such as resin, and a cathode (not shown) for energizing the workpiece 30 accommodated in the barrel 10. Are separately provided inside the barrel 10. Moreover, in order to accommodate the to-be-plated object 30 in the barrel 10, the one end surface part 12 is a detachable lid, for example.

  As shown in FIGS. 1A and 1B, a pump P (for example, a diaphragm pump) and an open / close valve 51 are arranged outside the plating tank 50 filled with the plating solution 40, and the inside of the barrel accompanying the barrel plating process is arranged. A suction nozzle 52 for sucking gas is connected to the suction side of the pump P through an open / close valve 51. The discharge side of the pump P is connected to a return conduit 53 into the plating tank 50.

  As shown in FIG. 1A, when electroplating is performed, the barrel unit 1 having the barrel 10 containing the object to be plated 30 is horizontally placed in the plating tank 50 filled with the plating solution 40. That is, the unit mounting table 51 on which the barrel unit 1 is mounted is installed in the plating tank 50, but the upper surface of the unit mounting table 51 is kept horizontal. And while applying a DC voltage between the anode in the plating tank 50 which is not shown in figure, and the cathode in the barrel 10, barrel plating is performed, rotating the barrel 10 with a horizontal rotating center axis | shaft. At this time, the pump P is stopped, the open / close valve 51 is closed, and the suction nozzle 52 is retracted to a position that does not hinder the rotation of the barrel 10.

  At the start of barrel plating, when the air in the barrel 10 is not completely removed, or as a result of continuing the barrel plating process, the gas accompanying the electroplating is accumulated in the barrel 10 as shown in FIG. In addition, it is necessary to suck the gas in the barrel. At this time, when the barrel 10 is not tilted, small gas bubbles are dispersed in the longitudinal direction, and reliable suction is difficult, so one of the barrels 10 as shown in FIGS. 1 (B) and 4 (B). The gas in the barrel is collected at the upper part of the inner space of the inclined barrel 10. For this reason, the unit mounting table 51 in FIG. 1B functions as an inclination means that inclines with the inclination center Q as a fulcrum, and inclines the entire barrel unit 1 that holds the barrel 10.

  And when performing suction of the gas in the barrel when the barrel is stopped, the suction nozzle 52 is inserted into the suction opening hole 21 in the uppermost position of the higher end surface portion 12 of the inclined barrel 10 or is made to face the proximity. By operating the pump P and opening the opening / closing valve 51, the gas in the barrel collected in the internal space on the higher side of the barrel 10 is sucked and removed together with the plating solution. At this time, it is necessary to minimize the amount of suction to the pump P in order to keep the plating solution level fluctuation to a minimum, and the suction nozzle 52 has a pinpoint suction structure that efficiently sucks a limited minimum area. desirable. When suction for a predetermined time is finished, the opening / closing valve 51 is closed and the pump P is stopped. Here, the on-off valve 51 is used in order to reliably perform on / off control of suction and to prevent backflow.

  The plating solution sucked together with the gas in the barrel by the pump P is returned to the plating tank 50 after releasing the gas in the barrel to the outside through the return pipe 53.

  According to this embodiment, the following effects can be obtained.

(1) Even when the mesh of the barrel 10 becomes fine corresponding to the object to be plated 30 such as a micro chip component (in other words, when the fine through hole through which the plating solution passes becomes small), the barrel is forcibly Since the gas in the barrel is sucked from the outside by the suction nozzle 52, the gas in the barrel is surely removed.

(2) Utilizing the property that the gas moves to the upper part of the internal space of the barrel 10 and collects it, the parallel barrel is tilted slightly obliquely only during suction, and the suction opening at the end surface (upper end) perpendicular to the barrel rotation axis By providing the hole 21 and suctioning from the outside using the suction nozzle 52, more reliable and efficient gas suction is possible (if the barrel is not tilted, small gas bubbles are formed in the longitudinal direction). It is in a dispersed state, making it difficult to assure reliable suction).

(3) The structure on the barrel unit 1 side is only required to provide the suction opening hole 21 in the end surface portion 12 of the barrel 10, and the suction mechanism including the suction nozzle 52 and the pump P for sucking the gas in the barrel is the barrel unit. 1 A mechanism provided outside, a suction mechanism can be commonly used for a number of barrel units 1, and the cost of plating equipment can be reduced.

(4) Since the barrel 10 is returned to the horizontal position during plating, there is no influence on the plating due to the tilt during suction.

  In the above embodiment, the barrel 10 is stopped when the barrel gas is sucked. However, the barrel gas can be sucked while the barrel 10 is rotating. In this case, in the inclined state of the barrel 10 in FIGS. 1B and 4B, the suction nozzle 52 is not inserted into the barrel side suction opening 21 in FIG. In this state, the suction operation may be performed.

  Moreover, in the said embodiment, although the barrel was set as the structure which provided the mesh member inside the cylindrical part and the end surface part, the structure which uses the cylindrical part itself as a mesh member may be sufficient.

  Although the embodiments of the present invention have been described above, it will be obvious to those skilled in the art that the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS It is embodiment of the barrel plating method which concerns on this invention, Comprising: (A) is a front sectional view at the time of barrel plating process, (B) is at the time of the gas suction in a barrel. It is a perspective view which shows the structure of the barrel used by embodiment of this invention. It is the structure of the barrel used by the said embodiment, Comprising: (A) is a front sectional view, (B) is a side view. It is a state of generation of a gas in a barrel and a suction method in the embodiment, wherein (A) is an explanatory view showing a state of generation of a gas in a barrel before tilting the barrel, and (B) is a gas in the barrel after tilting the barrel. It is explanatory drawing which shows a mode and a suction method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Barrel unit 2 Support frame 10 Barrel 11 Cylindrical part 12,13 End surface part 15,16 Shaft body 17 Mesh member 20 Small hole 21 Opening hole for suction 30 To-be-plated object 40 Plating solution 50 Plating tank 51 Unit mounting stand 52 Suction nozzle 53 Return line M Motor P Pump

Claims (2)

In a barrel plating method in which a plating solution is allowed to pass but an object to be plated is not allowed to pass, the object to be plated is accommodated in the barrel, and the barrel is immersed in a plating solution to perform electroplating on the object to be plated.
A pump and a suction nozzle sucked by the pump are arranged outside the barrel, and the one end of the barrel is inclined so as to be higher, and the gas in the barrel collected in the inner space on the higher side of the barrel is sucked into the suction. Barrel plating method characterized by sucking with a nozzle.   The barrel has a cylindrical portion and end surface portions located on both sides of the cylindrical portion, and a suction opening hole is formed in one end surface portion, and the suction nozzle is disposed close to the suction opening hole. The barrel plating method according to claim 1, wherein the gas in the barrel is sucked in the inserted state.

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