JPH06280035A - Chemical plating device - Google Patents

Abstract

PURPOSE:To minimize the deposition of a plating metal on the surface of a plating tank by providing a baffle plate between a body to be plated and a vibrating and agitating means. CONSTITUTION:The vibration generated by a motor 21 is transmitted to a vibrating blade group 24 by a vibrating and agitating means through a vibrpting frame 22 and a vibrating rod 23. A baffle plate 29 is provided between the vibrating and agitating means and a body to be plated so that the body is not directly vibrated. The baffle plate 29 is formed with a perforated cylinder, etc. Consequently, a metal grain is not deposited on the wall of a chemical plating tank by the impact and vibration of a diaphragm.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a chemical plating apparatus.

[0002]

2. Description of the Related Art A conventional general chemical plating method comprises the following steps. Degreasing-Washing-Desmut-Water washing-Water washing-Acid dipping-Water washing-Dip Degreasing-Water washing-Activation-Water washing-Water washing- -Washing-Washing-Chromate treatment-Washing-Water washing-Dip-Dry Then, in the chemical plating step, after bathing the chemical plating solution in the chemical plating bath, the solution is heated, for example, 9
Although the object to be plated such as metal is heated by heating to 0 to 95 ° C., at this time, the metal to be plated is deposited on the surface of the plating tank. Therefore, various stirring means are adopted as a countermeasure against this. However, both have advantages and disadvantages, and satisfactory results have not been obtained. The most common stirring means is circulation stirring by a pump, but there is a problem that the stirring efficiency is poor, and aeration is an advantageous stirring means,
Since it tends to oxidize the plating solution, it is not preferable especially in a chemical plating solution in which the temperature of the plating solution is high. Further, in the prior art, the deposits deposited in the plating solution serve as nuclei to deposit the metal on the entire inner surface of the plating bath, which accelerates the consumption and decomposition of the solution. Therefore, in order to minimize this tendency, the liquid in the plating tank is regularly discarded, nitric acid is added to the plating tank, and the metal that has precipitated in the tank is dissolved and cleaned by leaving it for about one day and night. In the case of nickel plating, this work usually has to be done once a week.

[0003]

[Purpose] An object of the present invention is to provide a new chemical plating apparatus in which the metal to be plated on the surface of the chemical plating tank is not deposited as much as possible.

[0004]

The present invention relates to a chemical plating apparatus in which a baffle plate is provided between an object to be plated and a vibration stirring means in a chemical plating tank.

The vibrating and stirring means transmits the vibration by the vibrating motor to the vibrating plate in the liquid for generating the vibration at 15 to 60 Hz, preferably 20 to 40 Hz, and the present inventor based on transmitting this vibration to the liquid. This is a newly developed stirring means, the basic idea of which is as disclosed in JP-A-3-275130, and the modified stirring means is Japanese Patent Application No. 4-286544 on September 14, 1992. I am applying. It is surprising that this vibration agitation, when vibration by the vibrating plate is transmitted to the entire system, makes the entire system promptly homogenized as compared with stirring by a screw, and this phenomenon is not limited to liquid systems. The same is true for powders and granules, and it is being verified in an experiment in which colored sawdust was added to sawdust. The vibration plate has an amplitude of 2 to 30 mm, preferably 10 to 15 mm.

The vibrating plate may be vibrated uniformly as described in the above-mentioned publications and specifications, but one or two parts of the vibrating plate are connected to the vibrating shaft to vibrate. You can also In this case, when the liquid tank has a quadrangular shape, two vibration shafts may be provided at both ends of one side of the diaphragm, but one vibration axis may be provided at the center of the side. Further, one vibration shaft may be provided at one corner of the diaphragm. The diagonal side of the side to which the vibration axis is attached or the corners other than the corner to which the vibration axis is attached are supported by the fixed shaft. An elastic body on the fixed shaft,
For example, it is preferable to fix the diaphragm via rubber, spring, air spring or the like, but it is also possible to rely on the elasticity of the diaphragm itself. FIG. 4 shows a specific example thereof. The vibrating rods 1 and 2 are provided via a vibration transmitting rod 5 connected to a vibrating motor by any means, and the vibrating plate 6 is fixed to the vibrating rods 1 and 9 by using rubber pieces 8 and 9, while the fixed rod is fixed. 3,4
The supporting rubber pieces 10, 1 for supporting the vibration of the diaphragm 6.
1 is fixed, and the diaphragm 6 is connected thereto. The diaphragm 6 is
Vibration transmission rods 1, 2 with the supporting rubber pieces 10, 11 as fulcrums
Since the fan vibrates like a vertical axis in line with the vertical axis, it is possible to mix and stir liquids, powders, granules, etc. by holding this in a tank.

The vibrating plate in the vibrating stirring means is
It can be roughly divided into three types. (1) Width 2 to 10 along the periphery of the chemical plating tank
A type in which a large number of diaphragms of about cm are provided on the upper and lower sides (see FIGS. 1 to 3) (2) A type in which one or two diaphragms are provided on the bottom of the chemical plating bath almost all over the bath (see FIG. 4) (3) In the center of the chemical plating tank, instead of the propeller agitating blades, a large number of diaphragms of arbitrary shape having a size equal to or smaller than the length of the propeller are provided above and below (Patent application No. 4-286544), but the type (1) is particularly preferable.

1 to 3 show a plating apparatus provided with a vibration stirring means used in the present invention. The vibration stirring means transmits the vibration generated by the vibration motor 21 to the vibrating blade groups 24, 24, ... Through the vibrating frame 22 and the vibrating rod 23. The vibrating blade groups are installed on both sides of the chemical plating bath 25 as clearly shown in FIGS. The vibration frame 22 is attached to a pedestal 28 via a spring 26 and a pedestal 27 so that the vibration from the vibration motor 21 does not affect the tank 25 main body. The vibrating blade may be horizontal, but is preferably attached with a slight inclination. The degree of inclination is preferably 0 to 45 ° with respect to the horizontal direction, preferably 10 to 20 °. In this example, the setting was made at 15 °. The width of the vibrating blade is not particularly limited, but if it is about 30 mm or more, its effect is sufficiently exhibited. Usually 30-100m
m, preferably about 50 to 80 mm. The interval between the stirring blades is not particularly limited, but is usually 10 to 80 mm, preferably 30 to 40 mm, and 35 mm in this embodiment.
The interval. The positions of the left and right vibrating blades 24 may be at the same height, but they may be provided at slightly displaced positions. The uppermost vibrating blade is preferably located about 100 mm below the liquid surface. If it is provided above this, the liquid will be scattered, although it is somewhat different depending on the amplitude, which is not preferable. The lowest vibrating blade is preferably located about 50 mm above the bottom. The vibrating blade of the present invention has a width of 80 mm, a length of 400 mm, and an interval of 35 mm.

In the present invention, it is necessary to provide a baffle plate on the surface where the vibrating plate is present so that the vibration of the vibrating plate does not directly affect the object to be plated. Need not be provided. The baffle is
It can also be a plate provided with a large number of holes, that is, a perforated plate. However, the baffle plate of the present invention may be a cylindrical body in which four baffle plates are connected. FIG. 5 shows a vibrating means and a baffle plate when the vibrating means as shown in FIGS. 1 to 3 are provided on the left and right ends of the chemical plating tank (including a combination of a baffle plate made porous and a baffle plate not so). It is a top view which shows the example of a combination with. FIG. 5A shows four perforated plates 32, 32, 32 between the vibrating plates 31, 31 facing each other.
This is a case provided with a rectangular tubular body formed by surrounding a baffle plate made of 32, which is the most typical case of the present invention.
FIG. 5B is a cylinder formed by surrounding four baffle plates consisting of two porous plates 32 and 32 and two non-perforated plates 33 and 33 between opposed diaphragms 31 and 31. FIG. 5C shows a case where a body is provided, and two porous plates 32 and 32 are provided between the diaphragms 31 facing each other. 5D shows a modified example of the case of FIG. 5A, which is a circular cylinder, and FIG. 5E shows FIG. 5D.
In this case, the surface without the diaphragm is made non-porous. Further, the upper and lower sides of the cylindrical body in FIG. 5 may be open or closed, whichever is acceptable.

The object of the present invention is to prevent metal particles from precipitating on the wall of the chemical plating tank due to impact or vibration by the vibrating plate. On the other hand, in order to chemically plate the object to be plated, Metal particles must be deposited on the surface of the object to be plated. In the present invention, a baffle plate is used as a means for resolving this contradiction. However, in order to make the chemical plating bath uniform, the chemical plating bath in the container flows to such an extent that it allows some precipitation of metal particles. It is preferable that Therefore, it is preferable that at least a part of the baffle plate is a porous wall. Usually, the effective opening area is 20 to 60%.

The apparatus of the present invention can be used not only for metal plating of zinc, copper, nickel, cobalt, gold, silver or the like, but also for so-called composite plating in which a large amount of solid fine particles are added to a plating solution and co-deposited during plating. Can also be used to advantage. In the case of composite plating, it is necessary that the particles are first uniformly suspended in the plating solution in order to co-deposit the composite dispersed particles in the state of being uniformly dispersed during plating. The general solid particles have a specific gravity larger than that of the plating solution, and when added to the plating solution, most of them settle. Therefore, stirring is necessary to keep these dispersed particles in the liquid uniformly and in suspension for a long time.

[0012]

【Example】

Example 1 At a position shown in FIG. 5A, in a chemical plating tank having a vibration stirring means having the structure shown in FIGS. 2 and 3, the vibration stirring means 31, 31, baffles 32, 32, 32, 32 and the plated object 30 are arranged. Vibration motor 21 is 0.4K
The vibrating blade 24 has a width of 80 mm and a length of 4
Those having a thickness of 00 mm and a thickness of 1.5 mm are attached at intervals of 35 mm. The baffle plate is a square cylinder (no bottom and lid) in which four plastic plates are connected, and the baffle plates are plates having a large number of holes with a diameter of about 3 mm, and the opening area ratio is 50%. Is. To raise the temperature of the plating bath, an ordinary heating means such as an electric heater or a jacket is used. A chemical plating bath made of SUS-316 having the above-mentioned auxiliary equipment is provided with a plating bath consisting of the following solution I, and the solution is adjusted to 90
It was heated to ˜95 ° C., and Ni—P plating was performed on the object to be plated of metal such as iron, copper, copper alloy or aluminum. The immersion time of the object to be plated was 2 minutes each.
Plating could be continued for more than 4000 hours with one plating bath. Liquid I Liquid II Nickel sulfate 24 g / l 25 g / l Sodium hypophosphite 20 g / l Lactic acid 27 g / l 10 g / l Propionic acid 2 g / l-pH 4.5 5.0

Example 2 The same test as in Example 1 was conducted using the above-mentioned solution II as a plating bath. After all, it was possible to perform plating for 4000 hours or more with one plating bath.

[0014]

【effect】

(1) In the conventional method, it was necessary to replace the plating solution at a rate of about once a week, but according to the present invention, the number of times of replacement is significantly reduced, and in the case of normal nickel plating, it is almost the same. Can be used for twice as long. (2) After replacing the plating solution, the chemical plating bath must be washed with nitric acid and then with water, so the number of replacements of the plating solution is reduced, which means the number of operations and the amount of nitric acid and water used. The amount of waste nitric acid is also reduced. (3) In the case of composite plating, not only the extension of the normal use period of the solution but also the prevention of non-uniformity due to the occurrence of precipitation of the solution significantly improves the product quality. (4) According to the present invention, the step of passivation (nitric acid) is unnecessary from the steps of the chemical plating method described in the section of the prior art, and the chemical plating in the following steps is possible. Degreasing-Washing-Desmut-Washing-Washing-Acid immersion-Washing-
Immersion degreasing-water washing-activation-water washing-water washing-electroless plating-
Electroless plating-Washing-Washing-Chromate treatment-Washing-Washing-Dip-Dry It is not necessary to interrupt the plating operation. Even if chemical plating was performed for about 4000 hours or more, there was no metal deposit on the inner surface of the plating tank, and the liquid life was greatly extended. (5) The defective rate when the baffle plate is installed is about 1/3 of the plating defect rate when only the vibration stirring is used and the baffle plate is not installed.
Reduced to.

[Brief description of drawings]

FIG. 1 is a top view of a chemical plating apparatus used in an example of the present invention.

FIG. 2 is a side view of the chemical plating apparatus used in the example of the present invention.

FIG. 3 is a side view of the chemical plating apparatus used in the embodiment of the present invention as seen from the other side.

FIG. 4 is a perspective view showing an outline of a novel vibration stirrer used in the plating method of the present invention.

FIG. 5 shows a vibrating means and a baffle plate (particularly a baffle plate that is made porous and a baffle plate that is not so) when the vibrating means as shown in FIGS. FIG. 4A is a top view showing an example of a combination with a combination of FIG. 4A and FIG. 4A, and FIG. 4A is a case in which a square tubular body formed by surrounding a baffle plate made of four perforated plates between opposing diaphragms Yes, (b) is a case in which a cylindrical body made by surrounding four baffle plates consisting of two porous plates and two non-perforated plates between opposing diaphragms is provided, and (c) is a case , A case in which two porous plates are provided between opposed diaphragms, (d)
In the modified example of the case of (a), a circular cylindrical body is used. In the case of (d), the surface without the diaphragm is made non-porous.

[Explanation of symbols]

 1 Vibration Rod 2 Vibration Rod 3 Fixed Rod 4 Fixed Rod 5 Vibration Transmission Rod 6 Vibration Plate 7 Tank Bottom 8 Supporting Rubber Piece 9 Supporting Rubber Piece 10 Supporting Rubber Piece 11 Supporting Rubber Piece 21 Vibration Motor 22 Vibration Frame 23 Vibration Rod 24 Vibration blade (vibration plate) 25 Chemical plating tank 26 Spring 27 Pedestal 28 Stand 29 Baffle plate 30 Plated object 31 Vibration plate 32 Perforated plate (baffle plate) 33 Non-perforated plate (baffle plate)

Claims (3)

[Claims] 1. A chemical plating apparatus, characterized in that a baffle plate is provided between an object to be plated and a vibration stirring means in a chemical plating tank. 2. The baffle plate is a perforated cylindrical body.
The described chemical plating apparatus. 3. The chemical plating apparatus according to claim 2, wherein the open area occupied by the holes of the porous tubular body is 20 to 60%.