WO2007122471A1

WO2007122471A1 - Surface treatment installation for metallic parts, particularly by electrolysis

Info

Publication number: WO2007122471A1
Application number: PCT/IB2007/001013
Authority: WO
Inventors: Frédéric Vacheron
Original assignee: Golden Eagle Trading Ltd.
Priority date: 2006-04-21
Filing date: 2007-04-19
Publication date: 2007-11-01
Also published as: JP2009534530A; JP4413993B2; ES2390684T3; US20090057138A1; KR101121634B1; FR2900162A1; KR20090005333A; RU2398918C2; FR2900162B1; CA2647400C; PL2013383T3; BRPI0710160A2; PT2013383E; CA2647400A1; EP2013383A1; EP2013383B1; RU2008145889A; MX2008013525A

Abstract

Surface treatment installation (100) for metallic parts including an electrolytic cell (1) comprising a treatment liquid (20) in which the parts to be treated are immersed, characterised in that the parts to be treated are fixed on a pivoting drum (2) such that there is at least one rotation movement for each part in the cell, and in that the cell (1) comprises at least two electrodes (8a, 8b), while the drum is powered by an electrical power supply with polarity opposite to the electrode polarity, through at least one contact pad that is brought into contact on the drum drive ring.

Description

INSTALLATION FOR SURFACE TREATMENT OF METALLIC PARTS, IN PARTICULAR BY ELECTROLYSIS

The present invention relates to an improvement in the method of surface treatment of metal parts, by electrolysis and relates more particularly to a continuous electrolysis cell using the principle of immersion and transfer of parts.

The surface treatment of parts by electrolysis is a well-known method, which requires the implementation of an electric current for carrying out the treatment.

Electrolysis can be applied to metals, such as anodizing aluminum, anaphoresis which allows the electrolytic deposition of aluminum paint, steel treatments such as zinc plating, chromium plating, copper plating, nickel plating, cataphoresis, phosphating, copper treatments such as tin plating, but also electroplating treatments on non-metallic parts such as electroplating of plastic parts.

According to conventional electrolysis processes, the parts to be treated are: either attached to supports placed so as to remain immobile in the electrolytic cell. In this case an electrical contact, such as for example a copper V, placed on the edge of the tank allows to bring the current to the supports placed on the V and thus parts. By this method so that the electrical contact remains constant, the supports and therefore the parts must remain stationary. This method therefore does not prevent the formation of air bubbles and therefore a lack of treatment in the hollow parts of some parts, and results in a lack of homogeneity in the treatment. - either placed in bulk in electrolysis barrels. In this case, the mass-treated parts are brought into contact with a moving electrode placed in the barrel. The disadvantage of this method is that the parts put in mass and in rotation are damaged by friction against each other.

The object of the invention is then to overcome all or part of the disadvantages of existing methods and implementation facilities, as mentioned above.

For this purpose, the present invention relates to an installation implementing a surface treatment method for parts such as hollow parts or the like, in which the parts are immersed completely inside at least one treatment tank. containing a liquid characterized in that each hollow part is immersed by making it rotate so that the air bubbles that can be created inside the tank are driven from the inner wall of said part.

Thus, the metal surface treatment plant according to the invention comprises an electrolysis cell comprising a treatment liquid in which the treated parts are immersed, and is characterized in that the parts to be treated are fixed on a pivoting drum so that it is made for each piece in the tank, at least one rotational movement, and in that the tank comprises at least two electrodes, while the drum is fed with electric current of opposite polarity to that of the electrodes, by means of at least one contact pad which is brought into contact on the drive ring of the drum. According to a complementary feature, the tank comprises a set of contact pads, for example two times fifteen pads sandwiching the drive ring of the drum

According to another characteristic, the contact pads are movably mounted in translation towards the flanks of the ring, and are biased in abutment against the corresponding face of the corresponding flank by an elastic system such as a spring.

According to other features of the invention, the two lateral successions of pads are arranged in an arc having the center of the pivot center of the drum, while each of the contact pads is connected to a copper cable or braid connected to the power supply.

Note also that the outer periphery of the drum comprises a succession of slides, intended to receive by sliding cassettes serving as a support for the parts to be treated, and that the slides are equipped with flexible contact blades, which are fixed to the slides, to transmit the electrical contact of the slide to the corresponding cassette and therefore to the parts attached thereto, thus allowing the electrolysis to be carried out.

It should be added that the tank comprises a motor designed to rotate the pivoting drum by the cooperation of a toothed wheel (6) with a succession of pegs mounted parallel to each other, and between the two flanges of one of the sidewalls of the drum. .

According to another complementary feature, the tank comprises two electrodes connected to a negative or positive polarity, while the drum is fed at the opposite polarity, and that said electrodes consist of aluminum plates. Other features and advantages of the invention will become apparent from the description which follows with reference to the accompanying drawings which are given by way of non-limiting examples.

Figure 1 is an end view illustrating the vessel of the invention;

Figure 2 is a view from above;

Figure 3 is a side view;

Figure 4 is a view similar to Figure 1, but without the drum.

According to the method implementing the treatment plant of the invention, each piece is immersed in a tank, making it do at least one rotational movement such that the air bubbles may be created inside. of the tank are driven from the inner walls of said room.

According to the illustrated embodiment, a rotational movement of at least 90 ° is made to each piece, and preferably a rotation of 360 °.

According to this embodiment illustrated, a predetermined number of said parts is placed beforehand on a support or cassette (4) comprising at least one holding member to retain each of them.

According to this embodiment, the part treatment plant with the general reference (100) consists of a tank (1) comprising a drum (2), rotatably mounted inside the latter, along an axis horizontal (X, X '), on which the parts to be treated are fixed. According to the illustrated embodiment, the drum (2) comprises, at its outer periphery, a succession of slides (3) with an axis parallel to the axis of rotation of the drum, intended to receive for example by sliding the cassettes (4). serving as support for the parts to be treated.

The cassettes are for example those described in the European patent application EP-A-I 433 537 and comprise a set of parts supports for fixing on a single cassette several parts.

The tank (1) of the invention comprises a motor for rotating the pivoting drum (2) by the cooperation of a toothed wheel (6) with a succession of pegs (7) mounted parallel to each other, and between the two flanges (10a, 10b) of one of the flanks (10) of the drum, constituting the drive ring.

The tank (1) comprises for example two electrodes (8a, 8b) connected to a negative polarity for electrolysis of aluminum parts. It will be noted that these electrodes (8a, 8b) would be connected to a positive polarity in the case of electrolysis of a steel or copper part.

The drum (2) is advantageously titanium but it could be otherwise as for example plastic for treatments requiring a metal deposition such as zinc coating.

Said drum (2) is fed at the opposite polarity, that is to say positive in the case of anodization.

The electric current is distributed to the drum (2) by means of at least one contact pad (9) which is brought into contact with the drive ring (10) of the drum. According to one characteristic of the invention, the tank comprises a set of contact pads, such as for example (9) two times fifteen pads (9a, 9b, 9c, 9o), as illustrated more particularly in FIG. 4.

According to the illustrated embodiment, the electrical contact with the drum is by sandwiching the drive ring (10) between two sets of fifteen pads.

Said contact pads (9) are for example graphite, but could be in another material for other treatments.

Add that each of the pads (9) is movably mounted in translation to the flanks (10a, 10b) of the ring, and is biased against the corresponding face of the corresponding flank by an elastic system such as a spring.

Of course the two lateral successions of pads are arranged in an arc whose center is the pivoting center of the drum, as appears more particularly in Figure 1 and 4.

Thus the graphite pads rub on the walls of the moving flank to transmit the current to the entire structure of the drum, including slides (3) by which are retained the cassettes (4).

Each of the contact pads (9) is connected to a copper cable or braid (12) connected to the power supply (13). The graphite contacts rub on the flanks (10a, 10b) of the drive ring of the drum, thereby transmitting the current to the entire structure of the wheel, the slides (3) serving as support for the cassettes.

The slides (3) are advantageously equipped with flexible contact blades, which are fixed to the slideways, to transmit the electrical contact of the slideway to the corresponding cassette (4) and thus to the parts which are fixed thereto, thus making it possible to realize the electrolysis between the connected parts, polarized in this application example to the positive pole and the electrodes (8a, 8b).

It will be specified that, according to the preferred embodiment, the electrodes (8a, 8b) advantageously consist of aluminum plates polarized at the negative pole.

Add that the aluminum plates constituting the electrodes are arranged for example on either side of the drum near the walls of the tank, and extend parallel to the axis of rotation of the drum.

The tank (1) thus equipped and filled with an electrolytic solution such as sulfuric acid for anodizing the aluminum, makes it possible to anodize aluminum parts attached to the cassettes. By this system the electrolysis is performed on parts fixed to cassettes performing a transverse movement and rotation on the wheel, which allows for a continuous electrolysis on moving parts in the treatment tank.

Of course, the invention is not limited to the embodiments described and represented by way of examples, but it also includes all the technical equivalents as well as their combinations.

Claims

A surface treatment plant (100) for metal parts, comprising an electrolysis cell (1) comprising a treatment liquid (20) in which the treated parts are immersed, characterized in that the treated parts are fixed on a pivoting drum (2) so that at least one rotational movement is made for each part in the vessel, and in that the vessel (1) comprises at least two electrodes (8a, 8b) while the drum is supplied with electric current of opposite polarity to that of the electrodes, by means of at least one contact pad (9) which is brought into contact with the drive ring (10) of the drum.

2. Treatment plant (100) according to claim 1, characterized in that the vessel comprises a set of contact pads (9), such as for example two times fifteen pads (9a, 9b, 9c, 9o).

3. Treatment plant (100) according to claim 2, characterized in that the electrical contact with the drum is by sandwiching the drive ring (10) between two sets of fifteen pads.

4. treatment plant (100) according to claim 3, characterized in that the contact pads (9) are made of graphite and are mounted movably in translation to the flanks (10a, 10b) of the ring, and are biased in support against the corresponding face of the corresponding flank by an elastic system such as a spring.

5. Treatment plant (100) according to claim 4, characterized in that the two lateral successions of pads are arranged in an arc having the center of the pivot center of the drum.

6. Treatment plant (100) according to claim 5, characterized in that each of the contact pads (9) is connected to a copper cable or braid (12) connected to the power supply (13).

7. Treatment plant (100) according to any one of the preceding claims _/ characterized in that the outer periphery of the drum comprises a succession of slides (3) for receiving by sliding cassettes (4) serving as a support for them. parts to be treated.

8. Treatment plant (100) according to the preceding claim, characterized in that the slides (3) are equipped with flexible contact blades (14), which are fixed to the slideways, to transmit the electrical contact of the slide to the cassette corresponding (4) and therefore to the parts attached thereto, thus making it possible to perform the electrolysis.

9. Treatment plant (100) according to any one of the preceding claims, characterized in that the vessel (1) comprises a motor for rotating the pivoting drum (2) by the cooperation of a toothed wheel ( 6) with a succession of pegs (7) mounted parallel to each other, and between the two flanges (10a, 10b) of one of the flanks (10) of the drum.

10. Treatment plant (100) according to any one of the preceding claims, characterized in that the tank (1) comprises two electrodes (8a, 8b) connected to a negative or positive polarity, while the drum (2 ) is powered at the opposite polarity.

11. Treatment plant (100) according to claim 10, characterized in that the electrodes (8a, 8b) consist of aluminum plates.