JPS60128295A - Device for automatic compensation and control of plating current - Google Patents

Abstract

PURPOSE:To improve the quality and corrosion resistance of plating and to improve electrode efficiency by controlling the distribution rate of plating to each plating cell according to the tracking of a strip so that plating current density can be controlled in a prescribed range. CONSTITUTION:A titled device is provided with a selection circuit 13 which selects the plating cells 3a-d to be conducted with electricity according to a line speed in prescribed order and a control circuit which compensates the excess or shortage of the coating weight of plating arising in the stage of changing the number of the cells. The above-described control circuits controls the distribution rate of the plating current to the cells 3a-d according to the tracking of a strip 1. The circuit controls the current according to the result obtd. by comparing the total sum of the plating current supplied to the cells 3a-d and the current reference compensated so as to obtain the plating current density in a prescribed range in accordance with the line speed of the strip 1.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention is directed to controlling the density of plating current within a certain range,
In particular, the present invention relates to a device for compensating for excess or deficiency in the amount of plating that occurs when changing the number of metal cells.

[Prior art]

Conventionally, this type of control device mainly controls the total current of the Metx cell without strictly controlling the current density. The plating current density is calculated by calculating the current value of each mesh cell from its electrode length and plate width, and the total current is calculated from the basis weight, plate width, electrode efficiency, and line speed. As long as these plating conditions do not change, the total current is controlled to be constant, and the amount of plating deposited is controlled to be constant. However, in the latest plating processes, it has become necessary to control the plating current to a constant value and to control the plating current density within a certain range. This is due to the need for higher gloss on the plated surface, improved electrode efficiency, and better corrosion resistance.

FIG. 1 is a block diagram of a conventional plating current automatic compensation control device. 1ii The strip to be plated moves in the direction of the arrow shown in the figure, 2 is a detector that detects the line speed of strip 1, 3a to 3d are metsuki cells that plate the strip 1, and 43 to 4d are platings supplied to metsuki cells 3a to 3d. A current detector, a rectifier that supplies a plating current of 5a to 5d, 68 to 6d a controller that controls the current supplied to the plating cells 3a to 3d via the rectifiers 5a to 5d to a predetermined value, and 73 to 7d a plating device Controllers 6a to 6d [distributor for distributing and supplying current, 8
is an adder that calculates the sum of plating currents based on the outputs of the detectors 4a to 4d, and a 9ViPI (proportional, integral) controller, which supplies output signals to distributors 7a to 7dK. 10 is a calculation circuit which calculates the difference between the line speed of the strip l obtained via the detector 2 and the current reference and supplies it to the adder 10a. The adder 10aV′i calculates the difference between the sum of the plating currents of the adder 8 and the output of the calculation circuit 10, and
supply to. Reference numeral 11 denotes a current reference circuit that calculates a total current reference from the basis weight, plate width, electrode efficiency, and line speed, and supplies this to the calculation circuit 10.

Next, the operation will be explained. The plating current supplied to each of the mesh cells 33 to 3d is detected by the detectors 48 to 4rJK,
Added by adder 8. The sum of the plating currents thus determined is calculated by an adder 10a as a difference from the total current reference of the calculating circuit 10, and is supplied to the controller 9. I) Current reference distributed based on MK given from I controller 9ij adder 10a to distributors 78 to 7d
supply to. The distributors 7a to 7d distribute the plating current to the controllers 63 to 6d, the rectifiers 58 to 5d, and the rectifiers 4a to 4d.
It is supplied to Metxcells 33 to 3d via 4d.

The line speed of the strip 1 detected by the detector 2 is input to the calculation circuit 101C, and the calculation circuit 10 increases or decreases the total current reference set by the current reference circuit 11 in accordance with the increase or decrease in this line speed. For example, when the line speed increases, the total current reference is increased.

In this way, conventional control devices determine the total plating current according to the moving speed of the strip, and change the current density of each mesh cell accordingly, making it impossible to control the plating current density within a predetermined range of values. There were drawbacks.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method.In order to compensate for excess or deficiency in the amount of plating that occurs when changing the number of mesh cells, the number of mesh cells is increased or decreased in a predetermined order. An object of the present invention is to provide an automatic plating current compensation control device that controls plating current density within a predetermined range by controlling the distribution ratio of plating current to each plating cell according to strip tracking.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Second
In the figure, parts with the same symbols as in FIG. 1 indicate the same parts, 12 is a lock contact connected between the controller 9 and the adder 10a, and 13 is a selection circuit that supplies selection signals to the distributors 7a to 7d. , 14 is a plating compensation circuit, a tracking circuit for the 15u strip 1, and 16 is a transmitter that generates a pulse synchronized with the movement of the strip 1 and inputs it to the tracking circuit.

Next, the operation will be explained. FIG. 3 is a graph showing the relationship between line speed and plating current density. As shown in the figure, the upper limit value Du and lower limit value DL of the current density are determined by the number N of metsuki cells. When the number of mesh cells is N/'i When the line speed increases to V', the upper limit value DUv' is reached (
Figure 3(a)). In addition, in the case of the number of mesh cells N+1, when the line speed decreases to V', DLv close to the lower limit value DL
' (Figure 3(b)). Therefore, line speed V
', the number of metsuki cells N becomes N1,000, or the number of metsuki cells N
+1 is changed to NK, and in the former case, the Metsuki cell 3a in the advancing direction of the IJ tube 1, that is, on the upstream side, is input (Fig. 3 (C)), and in the latter case, the Metsuki cell 3 on the upstream side is inserted.
a is stopped (FIG. 3(d)). As a result, as shown in FIGS. 3(e) and 3(f), as the number of metx cells increases or decreases, over- or under-plating occurs on the strip 1, which is compensated for by the process shown in the flowchart of FIG. 4. Note that explanation 8Ari which overlaps with the explanation of the conventional device will be omitted.

The case where the number of mesh cells is changed from N to N+1 at a certain speed during the speed increase shown in FIG. 3(a) will be described with reference to the flowcharts shown in FIGS. 2 and 4. When the line speed V reaches a certain mesh cell number changing speed v', the increase in the line speed V is temporarily stopped (held) (Pl). Next, the lock contact 12 is opened to lock the PE controller 9 for general current control (P2). Next, the Metsuki cell 3a is put in, and N+1- is set in the distributor 7a. The tracking circuit 15 is the Metsuki cell 3
Dragging is started by the pulse of the transmitter 16 at a specific point on the strip 1 that was at the entrance of the Metsuki cell 3a when the cell 3a was introduced. When this specific point reaches each cell entrance in the subsequent N mesh cells, the settings of each distributor 1 and 3a to 3d are sequentially changed from - to -1 (
P3). When the specific point reaches the exit of the N mesh cell, the tracking is terminated (P4), the hold on the line speed (P5) is released, and the lock of the PE controller 9 is released (P6), and this sequence is completed.

Similarly, the line speed ■ is 1, which is the planned value, and 1ii
Repeat the actions described above.

However, as shown in FIG. 3(b), when the line speed (■) is decreasing, the control is performed in the same way as when the line speed (■) is increasing.

The following points are different. That is, detachment of Menchicel 3a and 1
il of distributors 78 to 7d to the corresponding plating cells A/3b to 3
At the exit of d, the contents of the 1 distributors 7b to 7d1 are changed to N+1 swords 1 to K.

In the above embodiment, two examples will be explained in which the increase in the number of Menki cells is carried out in the direction opposite to the direction in which the number of Menki cells moves, and the decrease in the number of Menki cells is carried out in the direction in which the number of Menki cells increases in the direction in which the number of Menki cells increases. Regardless of anything, they are inserted or separated in a predetermined order.

〔Effect of the invention〕

As described above, according to the present invention, the number of mesh cells is increased or decreased according to a predetermined order, and in order to compensate for excess or deficiency in the amount of plating that occurs when changing the number of mesh cells, the distribution ratio of the plating current to each mesh cell is adjusted. Since it is configured to control according to tracking, the plating current density can be controlled within a predetermined range, improving the quality of plating.

Improvements in plating electrode efficiency and corrosion resistance can be obtained.
It has the effect of

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional plating current automatic compensation control device, FIG. 2 is a block diagram of a plating current automatic compensation control device according to an embodiment of the present invention, and FIG. 3 shows the operation of the device shown in FIG. 2. Characteristic diagram for explanation. FIG. 4 is a flow diagram of the operation of the apparatus shown in FIG. 1... Stringboo 2+4a to 4d... Detector,
3a to 3d... Menki cell, 5a to 5d... Rectifier, 6a to 6d... Controller, 7a to 7d... Distributor, 8° 10a... Calculator, 9... PI controller, 1o... Calculation circuit, 11... Current reference circuit,
12... Lock contact, 13... Selection circuit, 14...
- Compensation circuit, 15... Tracking circuit, 16...
transmitter. Note that the same reference numerals in Figure 0 indicate the same parts. Agent Masuo Oiwa (C) 3rd (d) 111 Raf Senno Ashiri (V) Continued from page 1 0 Inventor Haruo Kawamoto Inside Wadazaki-cho Control Works, Hyogo-ku, Kobe City 0 Inventor Hama 1) Osamu Shige Wadazaki-cho Control Works, Hyogo-ku, Kobe 0 Inventor Hata Shiiki 1-1-2 Wadazaki-cho Control Works, Hyogo-ku, Kobe 1-1-2 Mitsubishi Electric Corporation Mitsubishi Denki Co., Ltd. 1-1-2 Mitsubishi Electric Co., Ltd.

Claims (1)

[Claims] Each of the above plating currents is determined according to the result of comparing the sum of the plating currents supplied to multiple Metsuki cells with a current standard that is compensated to obtain a plating current density within a predetermined range corresponding to the line speed of the strip to be plated. The automatic plating current compensation control device includes a selection circuit that selects the mesh cells to be energized in a predetermined order according to the line speed, and a selection circuit that controls the distribution ratio of the plating current to the mesh cells according to strip tracking, and changes the number of mesh cells. 1. A plating current automatic compensation control device comprising: a control circuit for compensating for excess or deficiency in the amount of plating deposit that occurs at times.