JPH06326463A - Through-hole plating apparatus of printed wiring board - Google Patents

Abstract

PURPOSE:To enable a printed wiring board through-hole plating apparatus to be lessened in plating failure without being much modified in its equipment. CONSTITUTION:A swing bar 1 which is set swingable is provided close to a plating tank 2. A printed wiring board 4 provided with a through-hole 3 is set on a carrier 5, the carrier 5 is hooked on the swing bar 1, and the printed wiring board 4 is dipped into the plating tank 2. A vibrator 6 which gives vibrations to the swing bar 1 is mounted on the swing bar 1. The vibrations of the swing bar 1 by the vibrator 6 are transmitted to the printed wiring board 4 through the intermediary of the carrier 5, so that the printed wiring board 4 is vibrated to deaerate the through-holes 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a through hole plating apparatus for a printed wiring board used for manufacturing the printed wiring board.

[0002]

2. Description of the Related Art In manufacturing a printed wiring board, it is necessary to provide a through hole in the printed wiring board and to perform through hole plating on the inner circumference of the through hole. The through hole plating is performed on the printed wiring board by immersing the printed wiring board in a plating bath.

However, air bubbles may remain in the through holes to prevent the plating solution from entering the holes of the through holes, or the plating solution may not be able to enter the holes of the through holes due to surface tension or the like. There is a possibility that it may not be possible to perform through-hole plating on all of the many through-holes provided on the printed wiring board. In particular, when the through hole has a small diameter of less than 0.4 mm, it is difficult for the plating solution to enter the through hole, and defective defects in the through hole plating are likely to occur.

Therefore, a swing bar that is horizontally swung by a crank mechanism or the like is provided, and a carrier on which the printed wiring board is set is hooked on and supported by the swing bar so that the printed wiring board is immersed in the plating tank. By swinging the swing wiring bar to swing the printed wiring board in the plating tank, it is possible to remove bubbles from the through holes of the printed wiring board or to improve the wettability of the plating liquid to the through holes. There is. However, it is not possible to obtain high defoaming property and wettability only by rocking the printed wiring board with the rocking bar, and it is impossible to effectively prevent defective defects in through-hole plating.

On the other hand, in Japanese Unexamined Patent Publication No. 4-154192, the printed wiring board is dipped at an angle of 45 degrees or less with respect to the liquid surface of the plating solution, so that the bubbles in the through hole escape. I devised it to be easier. However, in the method disclosed in Japanese Patent Laid-Open No. 4-154192, it is necessary to use a carrier having a special structure in order to support the printed wiring board in an inclined manner, which requires a large modification in terms of equipment and defoaming. There was a problem that it was difficult to obtain the high effect of.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a through-hole plating apparatus for a printed wiring board, which can reduce defective defects in through-hole plating without requiring major modification of equipment. It is intended.

[0007]

In a through-hole plating apparatus for a printed wiring board according to the present invention, a swing bar 1 to be swung is disposed near a plating tank 2 and a through-hole 3 is provided in the printed wiring board. 4 is set on the carrier 5, and the carrier 5 is hooked on and supported by the rocking bar 1 to immerse the printed wiring board 4 in the plating tank 2 and the vibrator 6 for vibrating the rocking bar 1 is mounted on the rocking bar 1. It is characterized by being attached to.

In the present invention, the rocking bar 1 may be supported by the elastic body 7.

[0009]

The printed wiring board 4 can be vibrated in the plating tank 2 by vibrating the rocking bar 1 with the vibrating device 6, and this vibration allows a high defoaming property from the through hole and a plating solution for the through hole. It is possible to obtain high wettability. Further, it is only necessary to add the vibrator 6 to the swing bar 1, and the existing equipment can be used as it is.

[0010]

EXAMPLES The present invention will be described in detail below with reference to examples. Figure 1
1 shows an embodiment of the present invention, in which a pair of rocking bars 1 are provided along both side edges of a plating tank 2 containing a plating solution 10.
1 are arranged in parallel. The rocking bar 1 is formed in the shape of an elongated flat plate, and a plurality of substantially V-shaped receiving members 11 are provided on the upper surface thereof at a predetermined interval. The swing bar 1 is placed and supported on a receiving roller 12 attached to the upper edge of the opening of the plating tank 2 or in the vicinity thereof, and swing means (not shown) such as a crank mechanism driven by a motor. ) Is connected to the rocking bar 1. Therefore, the rocking bar 1 can be rocked on the receiving roller 12 by reciprocating in the longitudinal direction by operating the rocking means. A vibrator 6 is mounted on each swing bar 1. As the vibrator 6, any small one can be used such as a vibrator formed by eccentric to the rotation shaft of the motor, and by operating the vibrator 6, the swing bar 1 It is designed so that it can be vibrated.

As shown in FIG. 3, the receiving roller 12 is formed by rotatably pivoting a roller 14 on a bearing bracket 13, and an elastic body 7 such as a vibration-proof rubber is attached to the lower surface of the bearing bracket 13. Then, the receiving roller 12 is attached to the plating tank 2 or the like via the elastic body 7. The carrier 5 is a pair of left and right vertical rods 1.
A pair of upper and lower horizontal rods 16 and 16 are detachably installed between 5 and 15, and the printed wiring board 4 is detachably fixed between the vertical rod 15 and the horizontal rod 16 to be vertically oriented. It can be set to. A locking piece 17 is provided at the upper end of each vertical rod 15 so as to horizontally project outward.

When the electroless copper plating or the like is performed on the printed wiring board 4 provided with a large number of through holes 3, the printed wiring board 4 is set on the carrier 5 as described above. After that, the locking pieces 17 on both sides of the carrier 5 are hooked on the receiving members 11 of the pair of rocking bars 1 to print the carrier 5 while supporting the carrier 5 with the rocking bars 1 as shown in FIGS. 1 and 2. The wiring board 4 is immersed in the plating solution 10 in the plating tank 2. The oscillating means is operated to reciprocate the oscillating bar 1 in its longitudinal direction to oscillate the printed wiring board 4 in the plating solution 10, and the oscillator 6 is further operated to move the oscillating bar 1 to the oscillating bar 1. Vibration is applied to the printed wiring board 4 via the carrier 5 via the carrier 5 to vibrate the printed wiring board 4 in the plating solution 10. By vibrating the printed wiring board 4 in this manner, the bubbles 18 existing in the through hole 3 move as the printed wiring board 4 vibrates as shown in FIG. As shown in (b), it escapes, and degassing can be performed efficiently. Further, when the printed wiring board 4 is vibrated in the plating solution 10 as described above, the contact between the surface of the printed wiring board 4 and the plating solution 10 is improved and the wettability is enhanced. By increasing the defoaming property and wettability of the through hole 3 in this way, the plating solution 1
It is easy for 0 to enter, and it is possible to reduce defective defects in through-hole plating that occur when the plating solution 10 does not enter the through-hole 3.

The frequency and amplitude of the vibration applied to the printed wiring board 4 by the vibrator 6 can be appropriately set according to the specific gravity and viscosity of the plating solution 10, the surface tension, etc.
Frequency is 2500-4000 times / min, amplitude is 0.05-
It is preferably about 0.25 mm. By the way, the frequency is about 30
When through-hole plating was performed by applying a vibration with an amplitude of 0.1 mm at 00 times / minute, the defective rate of defective defects in through-hole was as low as 0.009%.

Here, when the elastic body 7 is provided on the lower surface of the receiving roller 12 as in the above embodiment, the swing bar 1 is supported through the elastic body 7, and the vibrating element 6 is used. The rocking bar 1 can be easily vibrated, the defoaming property and the wettability due to the vibration of the rocking bar 1 can be improved, and the vibration is prevented from being transmitted from the rocking bar 1 to the plating tank 2 or the like by the elastic body 7. Thus, noise and the like can be reduced. In addition to providing the elastic body 7 on the receiving roller 12 as described above, the receiving roller 12 itself may be formed of an elastic body 7 such as rubber or plastic, and the elastic body 7 is provided between the roller 14 and the bearing bracket 13. It may be provided. In short, the swing bar 1 may be supported via the elastic body 7. The present invention is applicable to all plating lines such as the desmear line of the printed wiring board 4, the panel plating line, and the pattern plating line,
It can be applied to treatment steps using other chemicals.

[0015]

As described above, according to the present invention, the rocking bar that is rocked is disposed near the plating tank, the printed wiring board having the through holes is set on the carrier, and the carrier is set on the rocking bar. The printed wiring board is immersed in the plating tank while being hooked and supported, and a vibrator that vibrates the rocking bar is attached to the rocking bar. It is possible to vibrate the printed wiring board, and this vibration can obtain high defoaming properties from the through holes and high wettability of the plating solution to the through holes, and reduce defective defects in the through holes. Is something that can be done. Further, it is only necessary to add a vibrator to the rocking bar, and it is possible to reduce defective defects in through-hole plating by using the existing equipment as it is without having to remodel the equipment.

Further, since the rocking bar is supported by the elastic body, it becomes easy to vibrate the rocking bar by the vibrator, and the defoaming property and wettability due to the vibration of the rocking bar can be enhanced. It is possible to reduce noise and the like by preventing the vibration from being transmitted from the rocking bar to the plating tank or the like by the elastic body.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is an enlarged perspective view of a part of the above.

FIG. 4 shows a state of defoaming, (a), (b)
FIG. 3 is an enlarged cross-sectional view of a part of the printed wiring board.

[Explanation of symbols]

 1 rocking bar 2 plating tank 3 through hole 4 printed wiring board 5 carrier 6 vibrator 7 elastic body

Claims (2)

[Claims] 1. A swing bar which is swung is disposed in the vicinity of a plating tank, a printed wiring board having a through hole is set on a carrier, and the carrier is hooked on and supported by the swing bar in the plating tank. A through-hole plating device for a printed wiring board, characterized in that the printed wiring board is dipped and a vibrator that applies vibration to the swing bar is attached to the swing bar. 2. The through hole plating apparatus for a printed wiring board according to claim 1, wherein the swing bar is supported by an elastic body.