CZ70596A3 - Method of producing metal layers by electroplating and apparatus for making the same - Google Patents

Abstract

The proposed galvanization process of making metal coating layers is characterized in that, the object to be subjected to galvanization is suspended within a space and electrolyte is supplied to the surface intended for galvanization by nozzles forming an anode, under pressure and in directed flow, whereby the nozzles change continuously their position with respect to the galvanized surface according to segmentation thereof. Each nozzle has electrically controlled voltage for maintaining current density at a predetermined value. The apparatus for carrying out the invented process consists of a supporting stool (3) with an eccentric (9) drive (6) secured thereto. The eccentric (9) drive (6) is coupled with a hollow plate (10), on which there is fastened at least one nozzle (11) passing through a swinging mounting arranged in a plate (12) being fixedly attached to the stool (3) and parallel to the hollow plate (10), whereby the stool (3) is coupled with an eccentric (8) having a drive (5) secured to a plate (2), on which there is fastened an eccentric (7) with a drive (4) attached to a main supporting plate (1). The hollow plate (10) is connected with a flexible tube (13) being connected with a pump (14), whose suction is connected to an electrolyte tank (15) that is interconnected with an electrolyte collecting tank (16), whereby each nozzle (11) is interconnected with the anode through a conductor (17) in which a current meter (18) is connected. The current meter (18) is connected with the input of an evaluation and control unit (21) whose output is connected with a voltage control element (19), while the object forming a cathode and intended for making metal coating layer thereon is slidably suspended on a load-supporting structure (23).

Description

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BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for the galvamination of metal layers, particularly on articulated articles and on the inner surfaces of cavities which are difficult to access.

BACKGROUND OF THE INVENTION

Previously known methods of electroplating of complex objects and inner surfaces of cavities are realized when the object is immersed in the electroplating of the bath, sometimes in the forced flow of electrolyte. The requirements for the technical parameters of the formed layers are considerable and the known methods do not sufficiently meet them. These are in particular the uniformity of the thickness of the layer, the homogeneity, the absence of defects such as hydrogen bubbles, the adhesion of the layer to the surface of the metal-plated object, the constant physical and mechanical properties of the layer.

Large-sized galvanoplastic products are obtained, for example, by using a rotational rocking of the product during the formation of the metal layer. This procedure is particularly suitable where it is necessary to place the anode in the cavity. The device for the realization of this method solves the invention of Czechoslovak. AO No. 261477.

Plating of the internal cavities is associated with considerable difficulties, especially in those cases where the outer surface of the product is not to be metallized, as is the case, for example, with the bore of internal combustion engine cylinders. This case is solved by the invention of MS. AO No. 250487, characterized in that it consists of a housing made of electrically insulating material, into which a part to be plated is inserted and an electrode placed in the cavity of the part and slidable into the sleeve, the sleeve mounted on the support structure having flow holes opening into the cavity through which the electrolyte washing the cavity walls is blown.

Plating of the inner surface of tubes of different diameters and lengths is solved, for example, by the invention. AO No. 242647 to a jig consisting of a carrier with at least one flexible liner in which split jaws are attached to fix the upper end of a tube which is retained at its lower end in a clamp fastened with a carrier to a pole to which the negative pole current. The positive terminal is connected via a collector to a bolt-shaped anode located in the tube cavity, on both ends of which there are insulating plugs with holes for electrolyte passage. The lower switchboard is connected to the lower end of the anode, which is connected firmly by a vertical conductive bar to the collector.

All these technologies are performed when the product is immersed in a bath. An exception is the narrowly specialized case of metallization of the inner surface of a pipe according to the invention. AO No. 252647, wherein the electrolyte is circulated by means of pumps through a metallized tube suspended in a vertical position.

Furthermore, a method is known in which a metal-plated article is placed in a sheath forming an equidistant surface with the surface of the article and the gap formed between the article and the sheath, by means of a pump, creating an electrolyte flow and thereby accelerating the formation of metallization.

SUMMARY OF THE INVENTION

The above-mentioned drawbacks are largely eliminated by the method of galvanically forming metal layers according to the invention, characterized in that the cathode-forming article for forming the metal layer is suspended in space and the electrolyte is fed to the metallized surface under pressure directed at least once. a nozzle connected to the anode, wherein the position of the nozzle relative to the surface of the metal-plated object varies according to the surface area of the metal-plated object. The current density value is predetermined for the various metals and is maintained at the same level during the electroplating process.

The device for the galvanic formation of metal layers comprises a support stool on which an eccentric drive fixed to the hollow plate is mounted, to which at least one nozzle extending through a pivot bearing in the plate is mounted rigidly supported on the support table and parallel to the hollow plate. A flexible tube connected to the discharge of the pump is connected to the hollow plate, the suction of which is connected to an electrolyte tank connected to an electrolyte collection tank. The support stool is rigidly connected to a second eccentric with a drive that is firmly seated on another plate also mounted on another eccentric driven by an electric motor fixedly seated on the main support plate mounted pivotably on the support structure. Each nozzle is connected to the anode by a conductor to which a current meter connected to the input of the evaluation and control block is connected. The control block output is connected to a voltage control element. The cathode object for forming the metal layer is slidably hinged to the support structure.

Overview of the drawings

The invention is explained in more detail in the drawing, which schematically illustrates a device for galvanically forming metal layers.

Examples of embodiments of the invention

Example 1

A copper layer was created on the model of the articulated heater. An acidic copper sulphate solution with sulfuric acid and brighteners was used as the electrolyte. The anode voltage ranged from 20 to 45 V and the current density was

O predetermined and maintained at 2.5 A / dm. The electrolyte was fed through one nozzle of 3.0 mm diameter made of titanium under a pressure of 100 kPa. The distance of the nozzle from the plated object was 25 to 50 mm. One eccentric was used to move the nozzle. After a 7 hour process, a uniform 0.5 mm thick copper layer with a purity of 99.8% was obtained.

Example 2

A copper layer was formed on the surface of the segmented radiator with height transitions of 20 mm. The electrolyte composition and operating parameters were the same as in Example 1. The electrolyte was fed through 20 nozzles 3.0 mm in diameter, 15 mm apart. The distance of the nozzles from the metallized surface was 20 to 60 mm. The movement of the nozzles was induced by two eccentrics with different speeds. After 12 hours of process, a uniform copper layer with a thickness of 0.6 mm was formed.

Apparatus for performing the method according to the invention comprises stool support to which is attached an electric motor driving a sixth cam 9 rigidly connected to the tube plate 1 0. hollow slab 1 0 j ^EOU nozzle 11 connected through a pivot bearing holes in the plate 12, fixedly mounted on the support stool The support stool 4 is rigidly connected to the eccentric 8, which is driven by an electric motor 2 supported by the plate 2. On the plate 2 is fixedly connected an eccentric 4 driven by an electric motor 4 mounted on a main support plate 7, which is pivotally mounted on the support structure. The hollow plate 10 is connected by a flexible tube 13 to the discharge of the pump 14, the suction of which is connected to the electrolyte reservoir 15 connected to the electrolyte collection tank 16.

Each nozzle 11 is coupled separately to the anode by a conductor 11 into which an electric meter 18 and a voltage control element 19 are inserted. The meter 18 is connected to the input of the evaluation and control block 21. the output of which is connected by a conductor 22 to a voltage regulating element 19. The object intended to form the metal layer is slidably suspended on the beam 23 ·

Industrial applicability

The method and apparatus for the galvanic formation of metal layers according to the invention are intended for use in the field of galvanic deposition of metals on objects of very complex shapes to obtain a uniform layer of deposited metal.

Claims (2)

PATENT CLAIMS 1. Method for the galvanic formation of metal layers, characterized in that the cathode-forming article for forming the metal layer is suspended in space and the electrolyte is fed to the metallized surface under pressure, directed by current, through at least one nozzle connected to the anode, the plated article varies according to the surface texture of the plated article and the current density is maintained at a predetermined value by varying the voltage at the anode. Device for carrying out the method according to claim 1, characterized in that it comprises a support stool (3) on which is mounted a drive (6) of the eccentric (9) which is connected to a hollow plate (10) on which it is mounted at least one nozzle (11) passing through the pivot bearing in the plate (12) fixedly mounted on the stool (3) and parallel to the hollow plate (10), the stool (3) being connected to an eccentric (8) with a drive (5) mounted on the plate (2), on which is mounted an eccentric (7) with a drive (4) mounted on the main support plate (1), on the hollow plate (10) is connected a flexible tube (13) connected to the discharge of the pump (14), connected to an electrolyte tank (15), which is connected to an electrolyte collection tank (16), each nozzle (11) being connected to the anode by a conductor (17) to which a current meter (18) connected to an evaluation and control block input is connected (21), the output of which is connected to the voltage regulating element (19), whereas the cathode object to form the metal layer is slidably hinged to the support structure (> 3).