JPH05156500A - Article supporting device for electroplating - Google Patents

Abstract

PURPOSE:To provide the article supporting device for electroplating having a mechanism for power feeding while applying rotation in such a manner that even a slight change in the diameter and length of a rod can be dealt with and the plating thickness is uniformalized even in both of a circumferential direction and an axial direction. CONSTITUTION:The end of the rod 1 is conductively supported via a suitable jig to a power feed flange 6 meeting the max. diameter of the rod 1 to be subjected to plating and this power feed flange 6 is rotated. One power feeder 24 is constituted movable over a range from the max. length to the min. length of the rod 1. Electricity is fed via a water cooled cable 16 to the power feeders 11, 24. As a result, the electricity is supplied while the rod 1 having the arbitrary diameter and arbitrary length is kept rotated in a horizontally supporting state, by which the plating with the uniform plating thickness is enabled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an article supporting apparatus for electroplating, and in an article made of steel or other material having a cylindrical or columnar shape, the entire or part of the circumferential surface thereof. For example, it can be used for applications in which chrome plating or other electroplating is performed with high precision in order to impart abrasion resistance and corrosion resistance.

[0002]

2. Description of the Related Art Conventionally, when the surface of a piston rod of a hydraulic cylinder or an air cylinder (hereinafter, simply referred to as "rod") is plated with chrome, the rod is erected vertically as shown in FIG. It was common to carry out the plating process in the state of being. In the figure, A is a cylindrical anode, and 1 is a rod plated with chromium. 2 is a plating tank and 3 is a plating chemical solution. Thus, rod 1
When the plate is plated vertically, the power is supplied only from the upper side of the rod 1 as shown in the figure.
There is a problem that the upper and lower current densities are different, and the axial plating thickness of the rod 1 is greatly different. Also, rod 1
Is difficult to install in the center of the anode A so that they are equidistant from the anode A. In particular, in the case of a long rod, since the liquid may not be transparent, it is difficult to know the positional relationship between the anode A and the rod 1 in the liquid, and the plating thickness is often measured not only in the vertical direction but also in the circumferential direction. There was a problem of exhibiting variations of. Furthermore, if the rod 1 is longer than 5 m, not only the corresponding depth of the plating tank and the height of the building are required, but also the variation in the vertical plating thickness tends to become larger. It was If such variations in plating thickness occur,
Since the rod has a function of sliding in the cylinder, there is a problem that it may cause oil leakage or air leakage.

Therefore, in order to eliminate the harmful effect of immersing the rod in the vertical direction, it is possible to immerse the rod 1 in the horizontal direction as shown in FIG. In this case, since the power can be supplied from both ends in the axial direction of the rod 1, the variation in the plating thickness in the axial direction is improved, but the liquid level direction and the anti-liquid level direction are separated from the anode A. In addition, there is a problem that the plating thickness varies in the circumferential direction. Therefore, if the rod 1 can be immersed in the horizontal direction and the rotation can be given in this state, all the above-mentioned problems can be solved, but in reality, the diameter of the rod 1 is large or small. Not only is there a long and short length, it is extremely difficult to give rotation, but it is difficult to feed power to both ends of the rod while giving rotation, and to date it has a large or small diameter. A configuration applicable to the length of the length has not been proposed.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object thereof is to cope with a slight change in the diameter or length of the rod. Not only that, but an object of the present invention is to provide an article supporting apparatus for electroplating, which is provided with a mechanism for supplying electric power while applying rotation so that the plating thickness is uniform in both the circumferential direction and the axial direction.

[0005]

In order to solve the above-mentioned problems, the article supporting apparatus for electroplating according to the present invention is intended to perform electroplating on the outer peripheral surface of an article having a cylindrical shape or a columnar shape. In the device of (1), the rotating mechanism that makes the axial direction of the article horizontal and that imparts rotation about the axial direction to the article in a state where the entire article is immersed in the plating chemical, and the rotating article On the other hand, it is characterized in that it is combined with a power supply mechanism for applying a current for electroplating.

Here, it is preferable that the power feeding mechanism includes a conductive power feeding flange having a diameter equal to or larger than a diameter of an axial end portion of the article, and the rotating mechanism is conductively coupled to the power feeding flange. It is preferable to provide a conductive rotating shaft and a bearing, which is wholly or partly made of an insulating material, as means for imparting rotation to the power feeding flange. Further, the power feeding mechanism is provided at both ends in the axial direction of the article, and at least one of the power feeding mechanisms is movable along the axial direction of the article and is fed by a flexible electric cable capable of supplying cooling water. Preferably.

[0007]

According to the present invention, in an apparatus for electroplating an outer peripheral surface of an article having a cylindrical shape or a cylindrical shape, power is supplied while the article is completely submerged in the plating chemical solution while rotating with the axial direction horizontal. Therefore, unlike the conventional vertical suspension method (see FIG. 3), there is no variation in the plating thickness in the axial direction of the article, and unlike the conventional horizontal placement method (see FIG. 4). Therefore, the plating thickness does not vary in the circumferential direction of the article.

Further, by making at least one side of the power supply mechanism provided at both ends of the article in the axial direction movable along the axial direction of the article, it is possible to cope with a change in the length of the article, Further, by using a power supply flange having a maximum diameter of the article or more, it is possible to cope with a change in the article diameter.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is an explanatory view showing its usage. In the figure, 4 is a cylindrical power supply shaft. The power feeding shaft 4 has a power feeding drum 5 at one end in the axial direction, and has a power feeding flange 6 at the other end in the axial direction. Power supply shaft 4 and power supply drum 5
The power supply flange 6 is made of copper or a copper alloy, or aluminum or an aluminum alloy. Reference numeral 7 denotes a bearing case, which supports the weight of the power feeding shaft 4 through a ceramic ball bearing 8 and allows the power feeding shaft 4 to rotate about a horizontal axis. Here, the ceramic ball bearing 8 is made of, for example, silicon nitride, alumina, or the like having excellent wear resistance, can be semi-permanently used without oil, and has an insulating property. The electric current for electroplating flowing through the power supply shaft 4 does not leak to the outside. The axial end of the steel rod 1 that is electroplated with a suitable jig is in conductive contact with the power supply flange 6, and the insulating lining 9 covers the portion other than the electroplated portion. There is. The sealing material 10 is in intimate contact with the outer peripheral surface of the insulating lining 9 to prevent the plating chemical 3 from entering the power supply device 11. The power supply device 11 is configured by applying an insulating coating process such as vinyl chloride resin or fluororesin to an iron case, and even if it is completely submerged in the plating chemical solution 3, its surface is not electroplated, and No infiltration of plating chemicals into the interior occurs. The power supply drum 5 is in conductive contact with a carbon power supply brush 12. Power supply brush 12
Are supported by the brush feeding disk 13 and are electrically connected. The brush feeding disk 13 is supported by the feeding plate 14 and is electrically conductively connected thereto. Power supply plate 1
4 is supported by the iron case of the power feeding device 11 via the insulating plate 15. A current for electroplating is supplied to the power supply plate 14 via a water cooling cable 16.
The water cooling cable 16 is composed of a water cooling type power feeding cable 17 capable of passing cooling water and a water feeding hose 18 for feeding cooling water to the power feeding cable 17. An electric current is supplied to the power supply cable 17 as shown by an arrow I in the figure, and a cooling water is supplied to the water supply hose 18 as shown by an arrow W in the figure. The weight of the iron case of the power supply device 11 is supported by a support pipe 19 that is horizontally installed. A drive transmission shaft 20 is fitted inside the support pipe 19. Drive transmission shaft 20
Has a sprocket 21, and its rotational force is transmitted from the sprocket 21 to the sprocket 23 of the power feeding shaft 4 via the chain 22. Therefore,
When the drive transmission shaft 20 rotates in the direction indicated by arrow C in the figure, the power feeding shaft 4 rotates in the direction indicated by arrow B in the figure.

Next, FIG. 2 shows a use state of the article supporting apparatus of the present invention. The plating bath 2 is filled with a plating chemical solution 3. A work such as a steel rod 1 is immersed in the plating chemical 3 with its axial direction being horizontal. Both ends in the axial direction of the rod 1 are fixed to the fixed power supply device 11
And is supported by the movable power supply device 24. The fixed power supply device 11 and the movable power supply device 24 are supported by the support pipe 19. The fixed power supply device 1 is provided in the support pipe 19.
The drive transmission shaft 20 for transmitting the rotational force is inserted into only one, and the power coupler 28 is coupled to the end portion thereof. In this embodiment, the movable power supply device 24 does not have a rotational force transmission mechanism. Electric currents for electroplating are supplied to the fixed power supply device 11 and the movable power supply device 24 via power supply cables (not shown). Both ends of the support pipe 19 are supported by hangers 25.
The hanger 25 is supported by a mounting table 26 installed adjacent to the plating tank 2. A hanging hook 27 is provided at the upper end of the hanger 25, and if it is configured so that it can be automatically lifted and lowered by a carrier such as a hoist crane, it can be used not only in the plating tank but also in the plating tank. It can also be used in a pretreatment tank and a cleaning tank after plating. Further, it goes without saying that it can be used not only for automatic plating equipment but also for ordinary plating processing that is performed manually.

The operation of this embodiment will be described below.
When the rod 1 is plated, the hanger 25 is lifted by using the suspension hook 27 and brought out of the processing tank. Then, in order to correspond to the size of the rod 1, as shown in FIG. 1, the end portion of the rod 1 is electrically conductive to the power feeding flange 6 corresponding to the maximum diameter of the rod 1 through an appropriate jig. It is something to support. As a result, it is possible to solve the two problems of supplying power to the rotating rod and rotationally driving the rods having different diameters at once. Further, in order to cope with the length of the rod 1, one of the power feeding devices 24 can be moved over the range from the maximum length to the minimum length of the rod 1 to be plated.

As described above, according to the diameter and length of the rod 1, the fixed power feeding device 11 and the movable power feeding device 24 are connected to the rod 1.
After supporting both ends of the hanger, use the carrier to hanger 2
After 5 is lowered to the pretreatment tank and subjected to the pretreatment, the hanger 25 is lowered to the plating tank 2 by automatic lifting and lowering and automatic feeding. Here, when a current required for electroplating, particularly a large-capacity direct current such as chromium plating, is used, it is difficult to provide a stable current to the moving power supply device 24, and it is difficult to apply the current from the related art. In the case of so-called solid bus bars that use copper or aluminum plates, in order to pass a sufficient current, it is necessary to increase the cross-sectional area of the conductive part, which not only causes excessive weight, but also causes the electrical contacts to move. Moreover, since the contact point is a metal that is easily oxidized, such as copper or aluminum, the contact resistance constantly changes, making stable power supply difficult. In order to solve this, the present apparatus uses a water-cooled cable which is flexible and can supply a large amount of electricity by passing water through a current-carrying material. In this way, the weight can be reduced by using the water-cooled cable for supplying a large capacity direct current. Also, because the cable itself is flexible, it can be expanded and contracted by mounting it on a flexible cable rack,
Since the electric contacts are fixed, compared to the case where the electric contacts are constantly moved, stable electric power can be supplied, and the movement of the power supply device becomes extremely easy. When the hanger 25 is placed on the stand 26, the electrodes provided on the stand 26 and the hanger 2 are
If the water-cooled cable 5 is contacted, the entire plating process can be easily automated, which is very convenient.

Next, in order to give rotation to the rod 1, rotation is given from the outside through a power coupler 28 by a motor with a reduction gear or the like, and the drive transmission shaft 20 in the support pipe 19 is given.
Is rotated as indicated by arrow C. As a result, the sprocket 23 is passed through the sprocket 21 through the chain 22.
The rotational force is transmitted to the power feeding shaft 4, and the power feeding shaft 4 rotates as shown by an arrow B. Since the carbon-made power feeding brush 12 receiving a large amount of direct current supplied from the water cooling cable 16 is pressed against the power feeding drum 5 formed integrally with the power feeding shaft 4 at a constant surface pressure. The DC current can be stably supplied to the power supply flange 6 via the power supply drum 5 and the power supply shaft 4. The power supply shaft 4 is made of a ceramic ball bearing 8 which is an insulator.
Therefore, since its weight and rotation are supported, leakage current does not flow to the outside.

As described above, by using the present apparatus, it is possible to supply electric power while rotating the rod 1 having an arbitrary diameter and an arbitrary length while horizontally supporting it, and it is possible to perform a plating process with a uniform plating thickness. It is possible. As an example, outer diameter 1
A sliding rod of a hydraulic cylinder for construction machinery having a diameter of 25φ, an inner diameter of 100φ and a length of 7,585 mm was subjected to chrome plating by using the article supporting apparatus shown in FIGS. 3, 4 and 2 with a target thickness of 30 μm. The chrome plating solution used was chromic anhydride 250 g / l and sulfuric acid 2.5 g / l, and chrome plating was performed at a liquid temperature of 50 ° C. for 2 hours. At this time, the applied current was 7500 A (about 25 A / dm ² ). Table 1 shows the result of measuring the chromium plating thickness (unit: μm) of the rod plated with chromium by each of the three methods with a non-destructive thickness gauge.

In Table 1, measurement points 1 to 16 mean respective equal points obtained by dividing the length direction of the rod into 16 equal parts, 0 degree, 1
Angles of 80 degrees, 90 degrees, and 270 degrees mean measurement points in the circumferential direction. In the vertical suspension method shown in FIG. 3, measurement point 1
Is the liquid surface side, and is 270 in the horizontal method shown in FIG.
The direction of the degree is the liquid surface side. As is clear from Table 1,
The chrome-plated rod using the article supporting apparatus of the present invention has a very uniform thickness distribution in both the length direction and the circumferential direction of the rod. Therefore, if it is used for manufacturing a rod for a hydraulic or air cylinder in which highly accurate plating thickness is indispensable, its quality can be greatly improved.

[0016]

[Table 1]

[0017]

According to the invention of claim 1, in an apparatus for electroplating an outer peripheral surface of an article having a cylindrical shape or a cylindrical shape, the axial direction of the article is horizontal, and
A rotating mechanism that imparts rotation about the axial direction to the article in a state where the entire article is immersed in the plating solution, and a power feeding mechanism that applies a current for electroplating to the rotating article. Therefore, there is an effect that a uniform plating thickness can be obtained in both the axial direction and the circumferential direction of the article.

According to the second aspect of the invention, since the article is rotated by using the conductive feeding flange having a diameter equal to or larger than the diameter of the axial end portion of the article, the article having a diameter larger than the maximum diameter of the article is provided. The use of the power supply flange has an effect of being able to cope with a change in the diameter of the article.

According to the third aspect of the present invention, since it has a conductive rotating shaft that is electrically conductively coupled to the power feeding flange, and a bearing that is wholly or partially formed of an insulating material, There is an effect that it is possible to prevent current from leaking from the rotating shaft to a portion other than the power supply flange.

According to the fourth aspect of the present invention, since at least one side of the power supply mechanisms provided at both ends of the article in the axial direction is movable along the axial direction of the article, the length of the article is increased. There is an effect that it is possible to cope with the change in the height.

According to the fifth aspect of the invention, since the cooling water is fed by the flexible electric cable capable of supplying the cooling water, the cross-sectional area of the conductive portion can be reduced as compared with the case of using the non-cooling electric cable. As a result, the weight of the electric cable can be reduced, and the power supply mechanism can be easily moved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a usage state of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a conventional example.

FIG. 4 is an explanatory diagram of another conventional example.

[Explanation of symbols]

 1 Rod 2 Plating Tank 3 Plating Chemical Solution 4 Feeding Shaft 5 Feeding Drum 6 Feeding Flange 7 Bearing Case 8 Ball Bearing 9 Insulation Lining 10 Sealing Material 11 Feeding Device 12 Feeding Brush 13 Brush Feeding Disc 14 Feeding Plate 15 Insulating Plate 16 Water Cooling Cable 17 Power supply cable 18 Water supply hose 19 Support pipe 20 Drive transmission shaft 21 Sprocket 22 Chain 23 Sprocket 24 Movable power supply device 25 Hanger 26 Stand 27 Hook for suspension

Claims (5)

[Claims] 1. An apparatus for electroplating an outer peripheral surface of an article having a cylindrical shape or a cylindrical shape, wherein the article has a horizontal axial direction and is entirely immersed in a plating solution. An article support for electroplating, characterized in that a rotation mechanism for imparting rotation about an axial direction to the above is combined with a power supply mechanism for applying a current for electroplating to the rotating article. apparatus. 2. The power feeding mechanism includes a conductive power feeding flange having a diameter equal to or larger than a diameter of an axial end portion of the article, and the rotating mechanism is means for imparting rotation to the power feeding flange. The article supporting apparatus for electroplating according to claim 1, wherein: 3. The rotating mechanism includes a conductive rotating shaft that is conductively coupled to the power feeding flange, and a bearing that is wholly or partially formed of an insulating material. An article support device for electroplating as described. 4. The power supply mechanism is provided at each end of the article in the axial direction, and at least one power supply mechanism is movable along the axial direction of the article. An article support device for electroplating as described. 5. The article supporting apparatus for electroplating according to claim 4, wherein the power feeding mechanism is fed by a flexible electric cable capable of supplying cooling water.