JPS6247960B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention is characterized in that the products to be connected to the cathode are successively immersed in the plating solution in the tank at one end of the anode plating tank, and the products are sequentially pulled up at the other end. Related to electroplating equipment.

(Prior Art) The plating tank is made to have a width suitable for the product and a length that allows the required amount of plating to be obtained when the product to be plated advances from one end of the tank to the other end. The anode plate extends almost the entire length in the longitudinal direction of the tank, and the busbar serving as the cathode is also provided along the entire length of the tank, and both are connected to both terminals of a single power rectifier.

For products that are thin, such as printed wiring boards, one piece at a time or several pieces are attached to a frame that is mounted on one plane.
Proceed through the tank using a chain conveyor, etc.

(Problem to be solved by the invention) In conventional equipment, when the first product (object to be plated) is placed in the plating bath at the start of plating work, the current is concentrated at the tip of the product. So-called scorching, discoloration, etc. occur on the parts. Furthermore, when the plating work for a series of products is completed, similar burns, discoloration, etc. occur on the rear end of the last product. Since this phenomenon is difficult to avoid, it was necessary to add a dummy to the first and last products to cover the defective plating parts to prevent this.

Note that only the first and last products mentioned above are bad, and the products before and after them are not perfect; the products near the first and last also have a high defect rate.

The above phenomenon occurs particularly when one end of a plate-shaped product such as a printed wiring board is advanced in the direction of travel, so it is troublesome to attach a dummy to that part. Therefore, it has not been possible to adopt a preferred product support method in which several plate-shaped products are arranged parallel to the traveling direction and the plating liquid between the products moves smoothly as the products progress.

The purpose of this invention is to fundamentally eliminate the above-mentioned scorching and discoloration phenomena in plating, and to improve the quality and efficiency of plating work by advancing printed wiring boards in parallel one by one.

(Means for Solving the Problems) In one aspect of the present invention which has achieved the above object, the products to be connected to the cathode are sequentially immersed in the plating solution in the tank at one end of the anode plating tank, In a device that sequentially pulls up at the end, the cathode is a sliding and rolling power feeding equipment installed along the longitudinal edge of the plating tank, and the anode is a sliding and rolling power supply equipment installed along the longitudinal edge of the plating tank, and the anode is a device in which a plurality of anode plates of different lengths are connected in series in the longitudinal direction inside the plating tank. the long anode plates in the middle of the row,
The electroplating apparatus is characterized in that short anode plates are placed at both ends of the row, and each anode plate is connected to its own power rectifier so that the supplied current can be individually controlled.

Similarly, part 2 is an apparatus in which the printed wiring boards connected to the cathode are sequentially immersed in the plating solution in the tank at one end of the anode plating tank, and then pulled up one after another at the other end. The anode is a bus bar installed along the longitudinal edge, and the anode is made by arranging multiple anode plates in series in the longitudinal direction in a plating tank.
Each anode plate is connected to its own power supply rectifier so that the supplied current can be controlled individually. A composite receiving frame having a drop-in opening and a supporting part, in which the plurality of boards mentioned above are placed in parallel at intervals at right angles to the above-mentioned supporting rods, is placed between the horizontal supporting rods of books, and both ends of each supporting rod of this receiving frame are placed and sent. The feeding mechanism provided along the side edge of the plating tank, the sliding or rolling power receiving part of the bus bar attached to the end of the conductive support rod, the support rod, and the respective substrates that connect each other. 1 is an electroplating apparatus for printed wiring boards characterized by comprising a connecting tool with a flexible power supply line.

(Function) The first invention above fundamentally eliminates the burnt and discolored plating described above. In other words, the conventional anode plate, which had a length equal to the entire length of the plating bath, was replaced with multiple anode plates arranged in series, and each was connected to a dedicated power rectifier to enable individual control. As the area of the product immersed in the plating solution increases, a correspondingly increasing current is supplied only to the shortest anode plate, and as the product advances and subsequent products enter,
Since power can be supplied sequentially to the anode plates on the sides of the first product, current is no longer concentrated all at once from the long anode plates to the first product, as was the case in the past.
Moreover, the anode plate at the end is short (in the direction of travel) and the current is gradually increased or decreased, so the plating current for the first and last products can be ideally adjusted.

In this way, there is no need to attach a dummy to the product, so if the product is a printed wiring board, the second part of this invention is a composite board that has a support part and a drop-in port that allows several boards to be lined up at intervals. (For mounting multiple boards together) A receiving frame is used, and this is moved using two horizontal support rods (front and rear), one of which is conductive, while sliding with the busbar to supply power, for the conventional hanging of boards. This greatly simplifies manual work, and allows the number of substrates corresponding to the width of the plating tank to be neatly stored in the receiving frame parallel to the direction of travel.
The process proceeds without disturbing the plating solution, improving efficiency and plating quality.

(Embodiment) Fig. 1 is a plan view of an embodiment of the present invention, in which the plating tank is T, the sliding and rolling power supply equipment (busbar) serving as the cathode for the plating current is 7, and the divided anode in the tank T is Board 9, power rectifier 11, then bus bar 7,
The wiring to the anode plate 9 is designated as 12. As can be seen in Figures 4 and 5, the four anode plates 9 are arranged in a row.
The products to be plated, in this case, five printed wiring boards P, are advanced in line one after the other, so that the anode plates 9 are placed between each of them so that they are lined up in four pieces. In this embodiment, only the lower part of the substrate P is plated.

In the conventional equipment for this embodiment, four anode plates extending the entire length of the tank T were arranged side by side, but in the device of the present invention, four short anode plates 9 were installed because they were separated in the longitudinal direction as described above. They are grouped together and connected to each rectifier 11 by wiring 12. In this case, the length of the anode plate 9 is the longest in the center and shorter towards the ends, so at the start of plating work, the receiving frame 1 containing the first five substrates is placed as shown in Figure 2. If the current supplied to the rectifier 11 is gradually increased in conjunction with the speed of submersion into the plating solution L, the substrate P
A current corresponding to the area in the liquid flows, and since the current enters only from the anode plate 9 directly beside each substrate P, the amount of plating is uniform.

After the first receiving frame 1 advances, the second receiving frame 1 enters, and when the two receiving frames 1 are immersed in the plating solution L, a current corresponding to the total substrate immersion area flows from the anode plate 9 right next to them. Do it like this. As three or four receiving frames 1 are added, the anode plates 9 at the front end will gradually start to work, but at that time, even if the current is applied to the substrate P from a slightly oblique direction, it will not have much effect. Therefore, the anode plate 9 at the center of the plating tank may be longer than those at the ends.

When a steady state is reached in which the receiving frame 1 moves along the entire length of the plating tank T, all the anode plates 9 flow into each substrate P from almost directly sideways, and each rectifier 11 also enters a steady state. Then, when the last receiving frame 1 advances in the tank, the anode plate 9 at the rear of the receiving frame sequentially stops power supply, and as the receiving frame 1 that has reached the outlet end is pulled up, contrary to when the cutting frame 1 enters, , a rectifier 11 with a short anode plate at the outlet end.
The power supply is gradually reduced according to the lifting speed of the receiving frame.

FIG. 3 shows an example of a supply current control device for a power supply rectifier. The detection device 13 may be a contact detector, a photoelectric detector, or any other suitable device, but may be provided as shown in FIG. 2, for example, and detects and transmits a signal just before the substrate in the receiving frame 1 comes into contact with the plating liquid L. The signal current passes through the amplifier section 14 and the variable resistor 15, controls the thyristor 17 of the supply current adjustment section, and adjusts the supply current to the bus bar 7. After the detection device 13 transmits,
Since the area of the substrate immersed in the plating solution gradually increases depending on the descending speed (constant) of the receiving frame 1, the variable resistor 1 is
By adjusting the resistance gradual decrease and gradual increase speed of the controller 16 of 5, the plating current can be gradually decreased or increased according to the immersion area. However, there are various means for detecting the start of immersion of the substrate P and the start of pulling up of the final substrate, and there is also a means for gradually increasing or decreasing the current supplied to the rectifier 11 in accordance with the immersion speed and the pulling speed. It can be left to the designer.

Next, with reference to FIGS. 4 to 6, the second part of the present invention, that is, a device mainly including the composite receiving frame 1 for improving work efficiency will be explained.

First of all, to list the parts numbers, the conductive horizontal support rod 2 of the receiving frame 1, the non-conductive horizontal supporting rod 3, the substrate drop-in port 4 of the receiving frame, the support part 5, the receiving frame feeding mechanism 6, and the sliding part mainly consisting of the bus bar. There are (transfer) dynamic power supply equipment 7, connectors 8 with flexible power supply lines, and the like. In this embodiment, the lower part of the substrate P is plated.

In this case, the composite support frame 1 is made by integrally making a support rod 3 made of vinyl chloride, the vinyl chloride part inside the conductive support rod 2, a board drop-in port 4, and a support part 5. Conductivity is obtained by adding a copper rod. The support part 5 with the drop-in port 4 has a thin box shape, is open to the bottom at the front and back, and hangs down parallel to the direction of movement, so that the plating liquid can flow onto the substrate P.
The plating action is stable as it washes both sides of the lower part. In this embodiment, as shown in FIG. 4, four anode plates 9 are erected side by side so as to fit between the respective supports 5, and their lower ends are connected.

The feeding mechanism 6 provided along both edges of the plating tank T is
In this example, a circulating belt conveyor is used, but any mechanism that carries the horizontal support rods 2 and 3 of the receiving frame 1 and horizontally moves the conveyor can be used. Incidentally, since any number of receiving frames 1 are placed one after another on the feed mechanism 6 and advanced without interruption, and are pulled up one after another at the end of the plating tank T and transferred to the next processing tank, the feed mechanism 6 may be operated in one direction.

The electrically conductive horizontal support rod 2 and the power supply rod of the sliding power supply equipment 7 are preferably copper busbars, but are not limited to copper. The sliding and rolling power supply equipment 7 may be a sliding power supply or a rolling power supply, and although the sliding power receiving plate 10 is attached to the lower surface of the support rod 2 in the figure, it may be a power receiving roller.

The connector 8 with a flexible power supply line for electrically connecting the conductive horizontal support rod 2 and the substrate P dropped into the receiving frame 1 may be a commonly used clip.

Although one embodiment has been described above, the embodiment of the present invention can be varied and applied in various ways within the scope of the gist of the invention.

(Effects of the Invention) This invention is based on an electroplating device that automatically plates products one after another, by dividing the anode, which conventionally extended over the entire length of the plating tank, and placing the long one in the center and the short one in the center. By arranging them at the ends, attaching a dedicated power rectifier to each anode plate, and making it possible to control the supply current for each anode plate, the board that enters the plating tank first also goes into the plating tank last. The substrate that comes out of the plating solution receives current only from the sides, and the supplied current can be increased or decreased in accordance with the increase or decrease of the area immersed in the plating solution. There was no inflow of plating current, and it became possible to obtain a plating layer of the required thickness uniformly over the entire surface.

In addition, if the product is a printed wiring board, we use a convenient composite receiving frame that aligns the number of boards that correspond to the width of the plating tank parallel to the direction of travel, so it is possible to
Without disturbing the plating solution, each board can effectively utilize the entire amount of stable plating solution and receive the aforementioned uniform current, that is, plating, greatly improving both work efficiency and plating quality at the same time. It is.

[Brief explanation of the drawing]

Fig. 1 is a plan view of one embodiment of this invention, Fig. 2 is an explanatory diagram showing a state in which a product is fed into one end of the plating tank, and Fig. 3 is an embodiment of the supply current control section of a power rectifier. Explanatory drawings, FIGS. 4 and 5 are an elevational view and a plan view of an embodiment of the composite receiving frame of the present invention, and FIG. 6 is a side view. 1...Composite receiving frame, 6...Feeding mechanism, 7...Sliding rolling power supply equipment (busbar), 8...Connecting tool, 9...Anode plate, 1
1...Power rectifier.

Claims (1)

[Scope of Claims] 1. In an apparatus in which products to be connected to a cathode are successively immersed in a plating solution in the tank at one end of the anode plating tank, and the products are sequentially pulled up at the other end, the cathode is connected to the plating tank along the length of the plating tank. This is a sliding and rolling power supply equipment installed along the edge.The above anode has multiple anode plates of different lengths arranged in series in the longitudinal direction in the plating tank, with the long anode plates placed in the center of the row and the short anode plates placed in the middle of the row. An electroplating apparatus characterized in that the anode plates are placed at both ends of the row, and each of the anode plates is connected to a dedicated power rectifier so that the supplied current can be controlled individually. 2. In a device in which printed wiring boards to be connected to the cathode are successively immersed in the plating solution in the tank at one end of the anode plating tank, and then sequentially pulled up at the other end, the cathode is provided along the longitudinal edge of the plating tank. The above-mentioned anode is a bus bar in which multiple anode plates are arranged in series in the longitudinal direction inside the plating bath, and each anode plate is connected to its own power rectifier so that the supplied current can be controlled individually. , The device for advancing the printed circuit boards by immersing them in a plating solution has a plurality of boards arranged in parallel at intervals in a direction perpendicular to the support bars between two horizontal support rods, one of which is electrically conductive. A composite receiving frame having a drop-in port and a supporting part, a feeding mechanism provided along the side edge of the plating tank so that both ends of each supporting rod of this receiving frame can be placed on it, and a feeding mechanism attached to the end of the conductive supporting rods. An electroplating apparatus for printed wiring boards, comprising: a power receiving part that slides or rolls with the bus bar; a connecting tool with a flexible power supply line that connects the support rod and each board;