JPH01159400A - Tin electroplating device - Google Patents

Abstract

PURPOSE:To always enable uniform, and stabilized tin plating without generating ununiform distribution of granules of tin by utilizing a basket having such a shape that the pressure between granules of tin for forming an anode is not raised. CONSTITUTION:The side plates 12b of a basket 12 are formed so that these can be opened to the outside directions at proper angle and the bottom plate 12a is tilted at proper angle downward to the intruding direction of granular tin 14. The pressure between granules of tin 14 which is generated by intruding pressure of the plunger 17 of an intruding means 15 provided to the lower part of a feed port 13 of granules of tin 14 of the basket 12 is gradually diffused along the intruding direction and made small and thereby ununiform distribution of granules of tin 14 to the crosswise direction of a strip 3 is not generated. Therefore a uniform interval between electrodes is held between the net face 12c of a basket 12 type anode, namely the uppermost face of the packed granules of tin 14 layer and the strip 3 traveling on the energized rolls 9 and becoming a cathode, and tin electroplating capable of forming uniform and stable film thickness can be performed via plating liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrolytic tin plating apparatus that supplies granular tin into a basket to form an anode.

[Conventional technology]

In general, electrolytic tin plating lines are broadly divided into alkaline lines and acidic lines based on the electrolyte used and line type, and acidic lines are further divided into ferrostane lines and halogen lines.

The plating equipment of the halogen line has a structure in which horizontal tanks are lined up in two stages, upper and lower, so that the strip passes horizontally.The degreased and pickled strip first enters the plating tank in the lower stage.
Only the lower side of the strip is plated. Next, it is turned over via a defleaf crawl and enters the upper plating tank, where the surface that was initially on the upper side is plated. The tin anode I used here is as shown in FIG.
Usually, it has a rod shape of 7621 m in length, 76 m in width, and 127 m in thickness, and a plurality of these are placed side by side on the main anode 2. The strip 3 is electrically plated by passing current between the conductive crawl 4 and the tin anode 1, which are brought into contact with each other, to form a cathode, so that the strip 3 travels directly above the tin anode 1 while maintaining a uniform pole spacing.

In addition, although charging or replacing the tin anode 1 into the plating bath is performed manually by the worker, the weight of each tin anode 1 is about 37 kg in the case of the above dimensions, so it is a burden on the worker. is large and workability is poor. Therefore, Japanese Patent Publication No. 59-33679 proposes an apparatus using a basket-shaped anode filled with granular tin instead of the rod-shaped tin anode (see FIG. 5). Fifth
In the figure, reference numeral 5 denotes a basket-shaped anode, the inside of which is filled with granular tin 7 supplied from a supply port 6.6. Reference numeral 8 denotes a membrane or plate-like member through which the plating solution passes but not the granular tin, so that the uppermost surface of the granular tin layer forms a uniform plane and is spaced apart from the strip 3 serving as the cathode by - It is designed to maintain

[Problem that the invention seeks to solve]

However, in equipment using such basket-type anodes, although there is no burden on the operator to load and replace rod-shaped anodes, as the granular tin is fed into the basket, the pressure between the granular tin increases. However, as the tin increases, the distribution of granular tin in the width direction of the strip becomes uneven, resulting in the problem that the plane formed by the top surface of the granular tin layer becomes uneven and the plating film thickness of the strip lacks uniformity. there were.

The present invention was made in view of these conventional problems, and an object of the present invention is to solve the above problems by creating a basket shape that does not increase the pressure between the tin particles.

[Means for solving problems]

The present invention provides an electrolytic tin plating apparatus that supplies granular tin into a basket horizontally arranged in a plating tank to form an anode, further comprising a granular tin pushing means provided at a lower part of a granular tin supply port of the basket. This electrolytic tin plating apparatus has a bottom plate of the basket inclined downward along the direction in which granular tin is pushed in, and both side plates of the basket are formed so that the cross section of the basket gradually expands in the left-right direction.

[Effect]

Since the present invention is configured as described above, the granular tin pushed into the basket by the granular tin pushing means is formed such that the shape of the basket gradually increases in cross-sectional area along the pushing direction. Therefore, the pushing pressure generated between the tin particles is diffused as the cross-sectional area increases, so that the pressure between the tin particles does not increase. Therefore, uneven distribution of granular tin in the width direction of the strip does not occur.

〔Example〕

The present invention will be explained below based on the drawings. FIGS. 1 to 3 are diagrams for explaining one embodiment of the present invention,
FIG. 1 is a cross-sectional view of the embodiment, and FIG. 2 is a plan view of the embodiment.

In the figure, 1■ is a plating tank, 12 is a basket placed in the plating tank 11 so that its top surface is horizontal,
It is submerged in the plating solution.

Reference numeral 13 denotes a supply port for the granular tin 14, which is provided at the smaller end of the basket 12, and below which is a pushing device 15, which is a means for pushing the supplied granular tin 14 into the basket 12. It is provided. 16 is a fluid pressure cylinder of the pushing device 15, and 17 is a plunger.

Reference numeral 12a denotes a bottom plate of the basket 12, which is inclined downward along the direction in which the granular tin 14 is pushed (arrow A). 1
2b and 12b are side plates of the basket 12, which are also formed so that the cross section of the basket 12 gradually expands in the left-right direction along the direction of arrow A. basket 1
The larger end of 2 is open. 12C is a net stretched over the open top surface of the basket 12, which allows the plating solution to pass through but not the granular tin, and this net 12c has a --shaped horizontal surface;
It is formed so as to be parallel to the strip 3 running horizontally directly above it and to maintain a -like spacing.

The basket 12 is placed on the main anode 18 in a state where it is always filled with the supplied granular tin 14, and becomes a basket-shaped anode when energized. On the other hand, the strip 3 running on the energizing roll 19 becomes a cathode when energized, and faces the net surface 12c of the basket-shaped anode 12, that is, the uppermost surface of the filled granular tin layer, while maintaining a pole spacing of -. Then, electrolytic tin plating is performed using a plating solution.

In addition, as the plating progresses, the part of the granular tin layer closest to the strip dissolves into the plating solution as metal ions, so it is consumed and the particle size becomes smaller, so new granular tin 14 is constantly added to the supply port. The dropped granular tin I4 is forced into the basket 12 by the reciprocating action of a plunger 17 attached to a hydraulic cylinder 16.

Here, the side plates 12b, 12b of the basket 12 are formed to open outward at a certain angle (referred to as opening degree), and the bottom plate 12a is inclined downward at a certain inclination angle along the pushing direction. Since the cross section of is shaped to gradually expand in the pushing direction, the granule pressure between the granular tin 14 caused by the pushing pressure of the plunger 17 is gradually diffused and reduced along the pushing direction. However, the opening degree of the side plate 12b and the inclination angle of the bottom plate 12a are set to such values that the pressure of the diffused particles becomes too small and a gap does not occur between the granular tin layer and the net surface 12c. ing.

Figure 3 shows the plunger pushing pressure (pushing force Fkg) when the opening degree of the side plate and the inclination angle of the bottom plate are set to specific values.
This is a graph obtained by actually measuring the relationship between the filling distance MX from the end face of the plunger 17 to the end face of the strip 3 using an experimental machine. , it is shown that the pushing force of the plunger is small. Therefore, such a basket 12
In this case, non-uniform distribution of granular tin in the width direction of the strip due to increase in granule pressure does not occur, so the distance between the electrodes and the strip 3 can be maintained uniformly, resulting in stable electricity with a uniform film thickness. Tin plating can be applied.

Further, the granular tin in the uppermost layer, which has been consumed as the plating progresses, is gradually sent to the open end of the basket 12 by the extrusion force F, and is discharged out of the plating tank 11 by a pump together with the plating solution. The large-sized granular tin mixed in at this time is automatically sorted and collected, and is again dropped into the supply port 13.

〔Effect of the invention〕

As explained above, according to the present invention, the pressure of the granular tin in the basket can be reduced, so the pushing force for supplying the granular tin can be reduced, and therefore the pushing means can be small and the strength of the basket can also be reduced. Since it is possible to reduce equipment costs, and since uneven distribution of granular tin does not occur, uniform and stable tin plating is always possible.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an embodiment according to the present invention, Fig. 2 is a plan view of the embodiment, Fig. 3 is a graph showing the relationship between the shape of the basket and the plunger extrusion force, and Fig. 4 is the first conventional example. FIG. 5 is a cross-sectional view of the second conventional example. 11... Plating tank, 12... Basket, 12a... Bottom plate, 12b... Side plate, 13... Supply port, 14... ...granular tin,
15... Pushing means. Patent Applicant Kawasaki Steel Co., Ltd. Agent Patent Attorney Tetsuya Mori Agent Patent Attorney Yoshiaki Shimizu Agent Patent Attorney Masaru Shimizu

Claims (1)

[Claims] In an electrolytic tin plating apparatus that supplies granular tin into a basket arranged horizontally in a plating tank to form an anode, a granular tin pushing means is provided at the lower part of the granular tin supply port of the basket, and further a granular tin pushing direction is provided. An electro-tin plating apparatus characterized in that the bottom plate of the basket is inclined downward along the line, and both side plates of the basket are formed so that the cross section of the basket gradually expands in the left-right direction.