DE417397C - Device for the electrolytic production of metallic protective coatings on sheets - Google Patents

Description

GERMAN EMPIRE

ISSUED ON AUGUST 10, 1925

REICH PATENT OFFICE

PATENT LETTERING

M 417397 CLASS 48 a GROUP 11

(K 8903g VI \ 48a)

Albert Knepper in Brussels.

Device for the electrolytic production of metallic protective coatings on sheet metal.
Patented in the German Empire on March 29, 1924.

According to the Union Treaty of June 2, 1911, priority is due to this application
of the application in Belgium of March 12, 1924.

The invention relates to the elec- 'but now the hooks one or more times

Trolytic coating of metal sheets with zinc. and it will not be a regular one

Tin, nickel, or any other metal. Achieved in rainfall. According to the present

In the following, by way of example, the invention is always more uniform, good

zincing of sheet metal can be described. adhesive coating produced in that

The simplest method for electro- during operation through the sheets

Lytic plating of sheet metal consists of current-carrying conductive brushes, which after

in that the metal sheets by means of hooks against possibility through insulating sheaths

Cathode support rods between two that make the current transfer to the electrolyte

Anode-forming rows of zinc plates are constantly brushed. In

to be hanged. While working in a similar fashion, the anodes can be brushed

will. However, the same can also be subdivided and preceded by strong current densities protected from pollution.

This has the following advantages: i. Application of an electrolyte whose chemical composition can vary within wide limits.

2. Application of any current density.

ίο 3. Use at will of rolled Zinc or zinc ingots in bars (first melt or electroplating bars) or unmelted Zinc.

In certain cases, even waste previously unsuitable for electroplating, such as old zinc sheet roofing waste, and zinc grains from hot-dip galvanizing plants or zinc smelters to be used.

4. The distance between the anode and Kaao method can be reduced to a minimum , whereby the power consumption can also be reduced to a minimum can.

5. The current distribution is particularly uniform for thin sheets.

6. Adherent, pliable, stretchable deposit of any thickness.

In the drawing is the overall arrangement with the details of the device according to illustrates the invention and some modified embodiments thereof, namely shows:

Fig. Ι the plan, Fig. 2 the longitudinal section, Fig. 3 the cross section, Fig. 4 a Detail of the brushing device,

Fig. 5 is a modification of Fig. 4, |

Fig. 6 two further modifications for be j

special purposes;

Fig. 7 the application with cast zinc plates, j

Fig. 8 the application of zinc waste,, Fig. 9 shows a device without brushing; the anodes, the latter being by a strong; Current density to be cleaned, j

Fig. 10 a brush-off device for the j Ivathode sheet with representation of the course j of the streamlines at this point.

ι denotes the tub the electrolyte containing 2 'in which a plurality of the anodes 3 forming zinc plate and a plurality of rows are arranged to be galvanized sheet 4 between the \ anodes. The anode carriers, which are easy to form, are not shown for the sake of simplicity. Support the sheets 4! on wooden strips 5, which are attached to uprights 6. The supports ξ, 6 are adjustable to one another according to the dimensions of the sheets to be galvanized. The sheets are firmly arranged.

There are moving frame 7 which \ carry the brush holder 8 between the anode and cathode plates. These parts 7, 8

■ are again arranged on other frames 9, which are carried by rollers 10 and by an eccentric 11 or any other

■ whose equivalent device received a reciprocating motion.

, Fig. 4 to 8 show details and changes to the brush holder. In these figures 12 designates the brushes themselves. 1 The device according to Fig. 4 is used for ^! Brushing off the anode and the cathode. 1 The device according to Fig. 5 serves the same purpose, but here the brushes are arranged alternately in order to reduce the distance between anode and cathode.

In Figs. 6, 7, 8, the device 8 ^{r is the} one which is preferably used when a higher current density is to be achieved on the anode than on the cathode: while 8 ^(/ denotes the device which is then preferably used If a higher current density is to be achieved on the cathode than on the anode. Supports 13 ", 13 *, iy can also be used to hold the metal sheets, especially if they are solid, instead of being brushed off Brushes 12 "brush the anodes; and brushes I2 ^C brush off the cathodes. The metallic part of the latter brushes is connected to the negative pole of the power source by means of a flexible, insulated copper wire and makes contact with the sheet metal to be galvanized.

The brushes 13 ″ could in a similar way be connected to the positive pole, but it is more convenient to connect them by a To connect clamping screw or other rigid connection with this pole.

Guides 14 are arranged above the galvanizing tub, which allow easy insertion of the sheets in the tub.

To operate the device, the eccentric disk 11 is turned on and the Plates inserted into the V-shaped guides 14, in which the same then through the Frame 5, 6 are held. As soon as they come into contact with a brush, the metal sheets are connected to the power source electrically connected, and galvanizing begins immediately. The going back and forth Movement of the frame carrying the brush sets all parts of the metal sheets one after the other Anodes opposite, and it is readily apparent that when the ratios between the individual parts are chosen correctly, all parts of the sheets one after the other and uniformly be subjected to the action of the electric current. The voltage loss resulting from the resistance of thin metal sheets can thereby be rendered harmless

be that a larger number of brushes is used. After a sheet during is exposed to the action of the current for a sufficient period of time, the same will be the case with a Pliers grasped and lifted out.

With this arrangement, all precautions are taken to avoid galvanizing and Prevent the brushes from getting dirty even if they are conductive. As shown in Fig. Io

ίο can be seen, are for this purpose the Side pieces of the brush sleeves arranged very broadly and only a few millimeters away from the sheet metal. Fig. Io shows the scatter of electrical lines. Very few streamlines reach the steel wires by the liquid, which are practically negligible.

When pulling out the sheets, however, there is the distance between the two wooden sides doubled, and as a result of the absence of the sheets, the scattering of the streamlines is increased. More precipitate forms on the brushes. In practice there is resistance the narrow slot between the wooden sides is still large enough to to prevent dirt.

A very small precipitate on the tips of the wires of the brushes is of no consequence, because the same is torn off by adjusting the following sheets or worn off by friction.

Since all parts of the moving frame are made of wood, zinc cannot precipitate the same are formed.

By using a sufficient number of auxiliary supports 13, short circuits are created avoided and the distance between anode and cathode as well as the galvanizing voltage reduced to a minimum.

In the device described above, the anode is brushed off. According to experience are galvanized anodes after a short ■ line with a black-gray, from the ' impure the zinc-derived layer!

coated, which offers a gradually increasing resistance to the electric current, generated very harmful side reactions in the electrolyte and therefore the correct ones The progress of the work. This j

"Io layer of dirt could now be brushed off by hand every day, but this is very '

is costly. The brushes 12 help this!

Evil from. j

The inconvenience can also be remedied by subjecting the anode to a sufficient current density which destroys the layer immediately when it is formed. To j such to allow the 'anode surfaces are partially covered by supports on the type of supports 13 and 8 * ^C. Another solution based on the same basic idea is shown in Fig. 9, where the anode plates are divided into individual strips which are placed across the cathode plates and are separated from one another by wood or other insulators.

Fig. 7 shows an arrangement for applying molten zinc, either in special-shaped rectangular bars 3 * or in current commercial bar 3 ^C. Such zinc bars always have an irregular surface, and the brush cleaning described above cannot then be used. However, strong current densities can then be used.

The arrangement according to Fig. 8 enables the use of old zinc waste from roofs or the like, zinc grains from foundry or hot-dip galvanizing etc. This waste 15 is poured into a basket 16, in the middle of which is a copper wire mesh 17 for making good contact with the pisitive Pole is arranged. For such waste, even higher current densities than for molten zinc must be used. Such current densities can be achieved due to the narrow gaps between the bars of the basket.

If the zinc is not brushed off, i. H. if molten zinc or zinc waste go can be used, according to Fig. 7, 8, the zinc forming the anode on the movable Frame to be arranged.

Claims (2)

Patent Claims: 1. Device for the electrolytic production of metallic protective coatings Sheet metal, characterized in that the power supply to the sheet metal is effected by conductive brushes which, according to Possibility to protect against the direct current transfer to the electrolyte, a relative movement against the metal sheets run while the anodes are either also by moving brushes or by strong current densities in the case of subdivision or partial covering of the anode surfaces can be secured against contamination. 2. Apparatus according to claim 1, characterized in that the brushes are surrounded by a covering formed by wood or other insulating material so that only a small amount There is space between the sheet to be galvanized and the insulating sleeve. 1 sheet of drawings.