JP2538591B2 - Method and apparatus for strip electrolytic treatment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to the strip and the electrode while supplying an electrolytic solution between the strip and an electrode facing the strip in a direction opposite to the traveling direction of the strip. The present invention relates to a strip electrolytic treatment method and apparatus for applying a potential difference between the strip and the strip.

<Prior art and its problems> In a conventional electrolytic treatment tank (counterflow type cell) for supplying an electrolytic solution between a strip and an electrode facing the strip in a direction opposite to the traveling direction of the strip, the electrolytic solution is used. The distance between the strip and the electrode was constant from the outlet side of the discharge nozzle to the inlet side of the electrolyte discharge nozzle.

 Hereinafter, a radial cell will be described as a typical example.

As shown in FIG. 5, a counter flow type radial cell 1 using a strip 2 wound around a winding roll 5 and a curved electrode 6 installed at a distance in the radial direction of the winding roll 5.
Then, between the electrodes on the inflow side of the electrolyte on the outlet side of the electrolyte discharge nozzle 7
Between the electrolyte discharge side electrodes on the inlet side of the electrolyte discharge nozzle 8
Up to 12, the distance between the strip 2 and the electrode 6 was constant (see, for example, JP-A-60-36697).

At this time, gas may be generated between the strip 2 and the electrode 6 by electrolysis. As an example, in electrolytic zinc plating with an insoluble anode in a sulfuric acid bath, oxygen gas is generated on the electrode surface. This gas mixes with the electrolyte flowing between the strip 2 and the electrode 6. As shown in FIG. 5, the mixed concentration gradually increases from the inflow side electrode gap 10 of the electrolytic solution to the discharge side electrode gap 12. Since the specific resistance of the electrolytic solution increases as the mixed concentration of the gas increases, the conduction resistance between the electrode 6 and the strip 2 gradually increases from the inflow side electrode gap 10 of the electrolytic solution to the discharge side electrode gap 12. Therefore electrolysis 6 to strip 2
The density of the current flowing to
It will be getting lower toward you.

However, alloy plating (for example, Zn and Ni) has the characteristic that the alloy composition of the plating metal changes depending on the current density. Therefore, when alloy plating is performed in a counter-flow radial cell, the alloy plating composition in the depth direction of the strip plating surface. There was a case that the non-uniformity occurred.

Japanese Patent Application Laid-Open No. 59-162298 discloses a solution to this drawback by removing gas, but there is a problem in that the structure of the electrode becomes complicated.

<Objects of the Invention> An object of the present invention is to solve the above-mentioned problems of the prior art, and to fix the gap between the strip and the electrode by the specific resistance of the electrolytic solution existing between the strip and the electrode facing the strip. It is an object of the present invention to provide a strip electrolytic treatment method and apparatus capable of changing the distance and making the current-carrying resistance due to the electrolytic solution between the electrodes uniform among all the electrodes to make the current density on the strip surface constant.

<Structure of the Invention> According to the first aspect of the present invention, a strip wound around a winding roll and traveling, and a curve that is installed facing the strip in a radial direction of the winding roll. In the electrolytic treatment section between the mold electrode, from the running downstream side of the strip,
The electrolytic solution is supplied and flows in the direction opposite to the strip traveling direction toward the upstream side of the strip traveling, and a potential difference is applied between the strip and the curved electrode to perform alloy plating treatment in the radial type electrolytic cell. In the electrolytic treatment method for a strip, the distance between the strip in the electrolytic treatment section and the curved electrode facing the strip is continuously reduced from the inflow side of the electrolytic solution to the discharge side, and the electrolytic treatment is performed. There is provided an electrolytic treatment method for a strip, characterized in that the electrolytic treatment is performed by making the current density uniform over the entire range from the inflow side to the discharge side of the electrolytic solution in the treatment section.

According to the second aspect of the present invention, a winding roll that winds and runs a strip that constitutes a cathode, and a curved electrode that faces the strip and is spaced apart in the radial direction of the winding roll. An electrolytic solution which is supplied to the electrolytic treatment section between the strip and the curved electrode in a direction opposite to the traveling direction of the strip from the traveling downstream side of the strip toward the traveling upstream side of the strip. In a strip electrolytic treatment apparatus for alloy plating in a radial type electrolytic cell having a supplying means and a means for applying a potential difference between the strip and the curved electrode, a curve facing the strip in the electrolytic treatment section and the strip. The strip electrolytic treatment apparatus is characterized in that it is provided with an inter-electrode distance adjusting means for continuously reducing the distance from the mold electrode along the electrolytic solution inflow side to the electrolytic solution discharge side. It is subjected.

Hereinafter, a strip electrolytic treatment method and apparatus according to the present invention will be described in more detail with reference to the accompanying drawings.

The electrolytic treatment method according to the present invention is applied to a method of alloy plating in a counterflow type radial electrolytic cell in which the running direction of the strip and the flowing direction of the electrolytic solution are opposite to each other, that is, the opposite direction. is there.

A counterflow type radial cell 1 used for carrying out the electrolytic treatment method for strips according to the present invention comprises two turn rolls 3 and 4 for guiding a strip 2 moving in a direction indicated by an arrow A, and a strip 2. The winding roll 5 to be attached and the electrode 6 which is installed so as to face the winding roll 5 and be separated from each other.
And an electrolyte solution discharge nozzle 7 for supplying the electrolyte solution between the winding roll 5 and the electrode 6, and an electrolyte solution discharge nozzle 8 for discharging the electrolyte solution containing the gas from the gap. The electrolytic solution discharge nozzle 7 is arranged on the downstream side of traveling of the strip 2,
The electrolyte discharge nozzle 8 is arranged on the upstream side of the traveling of the strip 2. Therefore, the electrolytic solution has a flow in a direction opposite to the traveling direction of the strip 2, that is, a counter flow.

Here, the inter-electrode distance between the winding roll 5 and the electrode 6 is large at the inflow-side interelectrode 10 of the electrolytic solution on the traveling downstream side of the strip 2,
It gradually decreases from the center pole 11 to the electrolyte discharge side pole 12 on the upstream side of travel of the strip 2,
It is configured so that the relative position of the winding roll 5 and the electrode 6 can be changed.

According to the method of the present invention, the strip 2 during the electrolytic treatment is guided by the turn roll 3 and directed toward the winding roll 5, is sufficiently wound around the winding roll 5, is deflected, and is guided by the guide roll 4. And is sent out in the direction indicated by arrow A.

At this time, by making the winding roll 5 an energizing roll, the strip 2 wound around the winding roll 5 serves as a cathode and the electrode 6 serves as an insoluble anode. Therefore, stripping is performed by the electrolytic solution flowing between these two electrodes. 2 is electrolyzed. At this time, when the strip 2 is electrolyzed, oxygen (O ₂ ) gas or the like is generated. However, the amount of gas contained in the electrolyte that flows between the two electrodes described above depends on the distance between the electrodes on the inflow side of the electrolyte.
10 is small, and increases as the distance between the central pole 11 and the discharge side pole 12 increases. Therefore, although the specific resistance of the electrolytic solution continuously increases from the inflow side electrode gap 10 to the central electrode gap 11 to the discharge side electrode gap 12, the distance between the strip 2 and the electrode 6 is the inflow side electrode gap. It is adjusted so that it continuously decreases from 10 to 12 between the discharge side electrodes.

Therefore, the energization resistance between the winding roll 5 and the electrode 6 can be made uniform over the entire electrode range of the electrolytic treatment section from the inflow side electrode gap 10 to the discharge side electrode gap 12 of the electrolytic solution. It becomes possible to carry out the electrolytic treatment while keeping the current density at each position of the electrolytic treatment section constant over the entire electrolytic treatment range.

Of course, corresponding to the amount of gas generated in the gap between the electrodes, when the amount of generated gas is large, the rate of change in the gap between the winding roll 5 and the electrode 6 is increased, and when the amount of generated gas is small, Adjust so that the rate of change in the distance between the poles is small. Here, for example, the adjustment amount of the inter-electrode distance may be previously obtained by performing an experiment for each operating condition, and the data corresponding to the actual operation may be used.

Next, the inter-electrode distance adjusting device that changes the relative positional relationship between the winding roll 5 and the electrode 6 will be specifically described.

The radial type electrolytic treatment apparatus shown in FIG. 2a, FIG. 2b, FIG. 3, FIG. 4a and FIG. 4b moves the electrode 6 or the winding roll 5 in the counter flow type radial cell 1 shown in FIG. Since the inter-electrode distance adjusting device is incorporated, detailed description of the radial cell 1 will be omitted below.
The radial type electrolytic treatment apparatus 20 shown in FIG. 2a and FIG. 2b fixes the radial cell 1 and the electrode 6 of the radial cell 1,
The inter-pole distance adjusting device 21 for moving the winding roll 5 in the line direction is provided. Here, the line direction indicates the strip transfer direction, that is, the direction indicated by arrow A and the opposite direction.

The pole distance adjusting device 21 includes winding roll bearings 22a and 22b that pivotally support the winding roll 5, bearing guides 23a and 23b that movably inscribe the winding roll bearings 22a and 22b, and a winding roll bearing 22a,
Electric screw jacks 24a and 24b for moving 22b are provided on both sides of the winding roll 5, and are provided on the drive side of the winding roll 5 so that the movement amount of the winding roll 5 is synchronized on both sides. It has a tuning shaft 25 that connects the electric screw jack 24b and the electric screw jack 24b on the opposite side, and a motor 26 that is a drive source of the electric screw jacks 24a and 24b.

The drive screw tip portions 27a and 27b of the electric screw jacks 24a and 24b are wound with a roll bearing 22 through a joint.
It is connected to a and 22b.

The winding roll bearings 22a, 22b move in synchronism with the movement of the electric screw jacks 24a, 24b, and the winding roll 5 moves and the distance between the fixed electrode 6 and the fixed electrode 6 is maintained over the entire electrolytic treatment section of the electrode. Can be changed.

The radial type electrolytic treatment device 30 shown in FIG. 3 fixes the radial cell 1 and the bearing of the shaft of the winding row 5 of the radial cell 1 and moves the electrode 6 in the line direction described above. Have and. The inter-electrode distance adjusting device 31 includes a support bar 32 that supports the electrode 6, a slide guide 33 that movably mounts both ends of the support bar 32, and a support bar.
And an electric screw jack 34 for moving 32.
The tip of the drive screw of the electric screw jack 34 is connected to the support bar 32 via a joint.

When the electric screw jack 34 is driven, the support bar 32 moves on the slide guide 33, the electrode 6 fixed on the support bar 31 moves in the line direction, and the winding roll 5 and the electrode 6 are moved. It is possible to change the distance between the contacts and.

Further, the radial type electrolytic treatment device 40 shown in FIGS. 4a and 4b is a gap distance adjusting device 41 for fixing the shaft bearings of the radial cell 1 and the winding roll 5 of the radial cell 1 to swing the electrode 6. Have and. The inter-electrode distance adjusting device 41 has a rotating shaft 43 that supports the electrode 6 at the electrode central portion 42, and an electric screw jack 44. One end of the rotary shaft 43 is fixed to the electrode 6, and the other end is fixed to one end of the link 45. The other end of the link 45 is an electric screw jack
It is rotatably attached to the tip of 44 drive screws.

By swinging the electric screw jack here, the rotary shaft 43 swings through the link 45 by a predetermined angle around the rotary shaft, and the electrode 6 fixed to the rotary shaft 43 is fixed to the electrode central portion 42. It is possible to change the distance between the electrodes 6 and the winding roll 5 by swinging about.

In the examples shown in FIGS. 2a, 2b, 3 and 4a, the electric screw jack was used as a means for moving the electrode or the winding roll, but what is possible if the electrode or the winding roll can be moved appropriately? For example, a hydraulic cylinder, an electric cylinder and a rack and pinion may be used. Further, the connection between the supporting member for supporting the electrode or the winding roll for moving and the moving means may be any.

Although the electrolytic treatment method and apparatus of the present invention have been described with reference to various examples using the radial cell as a representative example, the present invention is also applicable to horizontal cells and rigid cells.

The electrolytic treatment method and apparatus according to the present invention are basically configured as described above, but the present invention is not limited to these, and various improvements and designs can be made without departing from the scope of the present invention. Of course, it can be changed.

<Effects of the Invention> As described in detail above, according to the present invention, even if gas or the like is generated in the electrolyte flowing between the strip and the electrode facing the strip, the entire electrode range, Even if the energization resistance at each position of the entire electrolytic treatment section changes,
Since the current density in the entire electrode range can be adjusted to be constant by changing the distance between the electrodes at each position, the strip can be uniformly and favorably subjected to electrolytic treatment. Especially when alloy plating is applied to the strip,
The alloy plating composition in the depth direction of the alloy plating surface can be made uniform along the length direction of the strip.

Further, according to the present invention, only one of the electrodes, for example, in the case of a radial cell, only one of the winding roll or the insoluble anode that serves as the cathode is connected to the drive source, and is configured to move. Moreover, the distance between the strip and the electrode can be adjusted.

[Brief description of drawings]

FIG. 1 is a sectional view of a radial cell used for carrying out the electrolytic treatment method for strips according to the present invention. 2a is a sectional view of an embodiment of the electrolytic treatment apparatus for strips according to the present invention, and FIG. 2b is a sectional view taken along line II-II of FIG. 2a. FIG. 3 is a sectional view of another embodiment of the electrolytic treatment apparatus for strips according to the present invention. FIG. 4a is a sectional view of another embodiment of the electrolytic treatment apparatus for strips according to the present invention, and FIG. 4b is a partial sectional view of a radial cell incorporated in the electrolytic treatment apparatus for strips shown in FIG. 4a. FIG. 5 is a cross-sectional view of a radial cell in which a conventional strip electrolytic treatment is performed. DESCRIPTION OF SYMBOLS 1 ... Counter flow type radial cell, 2 ... Strip, 3, 4 ... Turn roll, 5 ... Winding roll, 6 ... Electrode, 7 ... Electrolyte discharge nozzle, 8 ... Electrolyte Discharge nozzle, 10 ... Electrolyte inflow side pole, 11 ... Central pole, 12 ... Electrolyte discharge side pole, 20, 30, 40 ... Radial electrolytic treatment device, 21, 31, 41 ...... Polar distance adjustment device, 22a, 22b ...... Rolled roller bearing, 23a, 23b ...... Bearing guide, 24a, 24b, 34,44 ...... Electric screw jack, 25 ...... Synchronizing shaft, 26 ...... Motor, 27a, 27b …… Drive screw tip, 32 …… Support bar, 33 …… Slide guide, 42 …… Electrode center, 43 …… Rotary shaft, 45 …… Link

Claims (2)

(57) [Claims] 1. An electrolytic treatment section between a strip wound around a winding roll and running, and a curved electrode facing the strip and spaced apart in the radial direction of the winding roll. The electrolytic solution is supplied from the downstream side of the strip running direction to the upstream side of the strip running in a direction opposite to the running direction of the strip, and a potential difference is applied between the strip and the curved electrode to provide a radial difference. In the electrolytic treatment method for strips for alloy plating in a mold type electrolytic cell, the distance between the strips in the electrolytic treatment section and the curved electrodes facing the strips is set continuously from the inflow side of the electrolytic solution to the discharge side. And the electrolytic treatment is performed by making the current density uniform over the entire range from the inflow side to the discharge side of the electrolytic solution of the electrolytic treatment section. 2. A winding roll that winds and runs a strip that constitutes a cathode, a curved electrode that faces the strip and is spaced apart in the radial direction of the winding roll, and the strip and the bend. Electrolyte solution supplying means for supplying the electrolytic solution in a direction opposite to the traveling direction of the strip from the traveling downstream side of the strip to the traveling upstream side of the strip, in an electrolytic treatment section between the mold electrode and the strip, and the strip. In a strip electrolytic treatment apparatus for alloy plating in a radial electrolytic cell having a means for applying a potential difference between the strip and a curved electrode facing the strip in the electrolytic treatment section. An electrolytic treatment apparatus for strips, characterized in that it is provided with an inter-electrode distance adjusting means for continuously reducing the distance from the inflow side of the electrolytic solution to the discharge side.