EP3438329B1

EP3438329B1 - Cathode stripping machine

Info

Publication number: EP3438329B1
Application number: EP16891324.2A
Authority: EP
Inventors: Yves Lefevre
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-02-25
Filing date: 2016-02-25
Publication date: 2020-12-16
Anticipated expiration: 2036-02-25
Also published as: MX2017000941A; EP3438329A4; RU2708280C1; EP3438329A1; ES2863596T3; WO2017144740A1

Description

Technical field of the invention

The present invention corresponds to the technical field of cathode stripping machines, which are necessary for separating the metal sheets obtained by electrolysis on said cathodes.

Background of the invention

There are metals that are in very high demand, which are obtained by an electrolysis process that causes the metal sought to be deposited on cathodes submerged in a specific solution. These cathodes tend to have a square or rectangular shape.
Once the material sought has been deposited forming a coating sheet or layer on the two faces of each of the cathodes submerged in the solution, said sheets must be removed from the cathodes. Initially this operation was carried out manually, resulting in a process that requires the intervention of labor intensive work and is slow and laborious, both due to the separating operation and due to the fact that it must be carried out on each cathode individually.
Currently, these aspects have greatly improved mainly due to the existence of machines that reduce the work and streamline the process.
However, they still have certain drawbacks due to the way in which the sheets are stripped with respect to the faces of the cathodes and that they are still fairly slow processes. Some of the forms of separation that were used consisted of striking the assembly with pneumatic hammers, which in addition to being very acoustically disruptive, after a short period of time the cathodes begin to show deformations due to the strikes.
The reference documents ES0372891 and ES2005673 can be mentioned as examples of the state of the art.
The first reference document ES0372891 relates to a hydraulic method for stripping the zinc deposited on the cathodes for the electrolytically obtaining the same, wherein once the cathodes are removed from the tank, each one of the faces thereof is subjected to a high-pressure water jet directed such that it impacts on the separation line between the aluminum sheet and the zinc deposited thereon, with a specific angle to cause the zinc to detach.
This method offers an alternative mode that prevents the surfaces of the cathodes from being damaged, but it is still slow since the separation is carried out on each cathode individually, and the cathodes and the pressurized water injectors must be accurately levelled so that the water accurately impacts on the waterline thereof and not elsewhere, since any small variation, due to the evaporation in the electrolysis tanks for example, would mean that the application of the water jet would not fulfil its purpose.
The reference document ES2005673 relates to a method for stripping electrolytically deposited copper from a cathode, wherein said cathode is subjected to bending stress at a magnitude greater than the adhesion strength between the deposited copper and the cathode, but without exceeding the yield strength thereof, thus making at least part of the copper deposited separate from the cathode, and the deposited copper can then be stripped, by means of a wedge or gas jet.
Again, it is a method that does not achieve high levels of production since each cathode must be treated individually with the gas jet or with a wedge and the cathodes must also be previously bent, which increases the time used and over time, the cathodes can break due to fatigue.

Description of the invention

The cathode stripping machine, which has a sheet-shaped metal deposit on each one of the two opposite faces thereof shown here, comprises a first operating level and a second reception level located below the first level.
The first operating level comprises an infeed mechanism of the cathodes, a first transfer mechanism for transferring said cathodes inside the machine, a treatment mechanism with a stripping head having two stripping frames, each acting on one cathode simultaneously, a second transfer mechanism for transferring the cathodes, and an outfeed mechanism of the cathodes without sheets.
In turn, the second level comprises for each of the resulting sheets, a sheet reception system, a conveyor belt, and a sheet removal station, as well as a shared collection and weighing table with rollers for both sheets.
In a preferred embodiment, the cathode reception mechanism of the first level comprises a parallel beam system, where a first beam is fixed and second beam is walking, the movement of which in a vertical direction is caused by a hydraulically actuated pivoting pusher assembly and the movement in a horizontal direction is caused by a synchronized double hydraulic cylinder assembly between them by means of a hydromechanical flow divider.
In accordance with a preferred embodiment, the first transfer mechanism for transferring the cathodes to the stripping mechanism is formed by an aerial chain conveyor and the second transfer mechanism for transferring the cathodes is formed by an aerial twin cable conveyor.
According to a preferred embodiment, each one of the two stripping frames of the treatment mechanism of the first level comprises cathode washing means, formed by a series of water manifolds with spray nozzles fastened to the stripping head.
Likewise, and in accordance with a preferred embodiment, each stripping frame of the treatment mechanism of the first level comprises first advance means of the cathodes along the stripping head, formed in each case by a walking beam mechanism actuated hydraulically that has an anti-sway system.
In accordance with another aspect, in a preferred embodiment, the treatment mechanism comprises a guided blade system for each one of the stripping frames of the cathodes, wherein said blade system is secured to the stripping head.
According to a preferred embodiment, the treatment mechanism comprises pre-stripping means for each stripping frame formed by a robot with a blade for each cathode.
In this case, and in a preferred embodiment, the treatment mechanism comprises pre-stripping starting means that have a frame with movable cutting means.
Moreover, said pre-stripping starting means are suitable for checking the level of adhesion between the cathode and the sheet thereon.
According to a preferred embodiment, the first operation level of this cathode stripping machine comprises a scrubbing frame located downstream from the second transfer mechanism and is formed by two scrubbing mechanisms, one for each one of the cathodes processed simultaneously.
Each one of said scrubbing mechanisms supports a scrubbing device and second advance means responsible for taking each cathode from the second transfer mechanism through the scrubbing frame and to the outfeed mechanism, wherein said second advance means are formed by a walking beam.
In this case and in a preferred embodiment, the scrubbing device comprises a lifting mechanism formed by a mobile trolley guided by means of vertical rails, a sub-assembly of brushes fixed to connecting rods and, an irrigation system formed by a series of manifolds provided with spray nozzles.
In accordance with a preferred embodiment, the sheet reception system of the second level comprises a damping system of said sheets formed by a hatch actuated by means of pneumatic bellows and a sheet accompanying system.
In this case and according to a preferred embodiment, the sheet reception system comprises two pairs of wheels downstream of the damping system actuated by means of electric geared motors in order to control the drop speed of the sheets.
In a preferred embodiment, the sheet removal station comprises a fixed reception frame, a reception robot and a guide device.
The stripping machine that is presented herein significantly improves upon the state of the art.
This is because the two cathodes are acted upon simultaneously, which means that the process time is considerably reduced.
In addition, the shape in which the machine is designed has a perfect control over the steps to be carried out, both for each pair of cathodes and for the sheets that detach therefrom. This is controlled through two, perfectly synchronized, levels of the machines that reduce the time used in stripping the cathodes and significantly increases the productivity of the machine.
In addition, the stripping is carried out with blades and a pre-stripping is carried out beforehand and a pre-stripping initiator, such that the sheets of the surfaces of the cathodes are separated without causing any damage or scratches thereon.

Brief description of the drawings

For the purpose of helping to make the characteristics of the invention more readily understandable, in accordance with a preferred practical embodiment thereof, said description is accompanied by a set of drawings constituting an integral part thereof which, by way of illustration and not limitation, represent the following:

Figure 1 shows a perspective view of the upper level of the cathode stripping machine, for a preferred embodiment of the invention.
Figure 2 shows a plan view of the upper level of the cathode stripping machine, for a preferred embodiment of the invention.
Figure 3 shows an elevation view of the cathode stripping machine, for a preferred embodiment of the invention.
Figure 4 shows a profile view of the cathode stripping machine, for a preferred embodiment of the invention.
Figure 5 shows a perspective view of the stripping mechanism of the cathode stripping machine, for a preferred embodiment of the invention.
Figure 6 shows a cross section of the blades of the stripping mechanism of the cathode stripping machine, for a preferred embodiment of the invention.

Detailed description of a preferred embodiment of the invention

In light of the figures provided, it can be seen how in a preferred embodiment of the invention, the cathode 5 stripping machine 3, which cathodes have a metal deposit in the form of a sheet on each one of the two opposite faces thereof that is presented herein, comprises a first operating level 1 and a second reception level 2 located below said first level 1. In this case, a machine with aluminum cathodes on which a sheet of zinc accumulates due to electrolysis is considered.
As shown in figures 1 to 4, the first operating level 1 comprising an infeed mechanism 4 of the cathodes 5 to the machine, a first transfer mechanism 8.1 for transferring said cathodes inside the machine, a treatment mechanism with a stripping head having two stripping frames 7, each acting on one cathode simultaneously, a second transfer mechanism 8.2 for transferring the cathodes, and an outfeed mechanism 9 of the cathodes without zinc sheets.
Likewise, as can be seen in figures 3 and 4, the second level 2 comprises for each of the resulting sheets, a sheet reception system 10, a conveyor belt 11, and a sheet removal station 12, as well as a shared collection and weighing table 13 with rollers for both sheets.
A crane is responsible for depositing the cathodes 5 in the infeed mechanism 4 thereof in the machine. In this preferred embodiment of the invention, said infeed mechanism 4 of the cathodes of the first level 1 comprises a parallel beam system, with a first fixed beam and a second walking beam. The movement of this second walking beam is caused in a vertical direction by a hydraulically actuated pivoting pusher assembly, while in a horizontal direction it is caused by a synchronized double hydraulic cylinder assembly between them by means of a hydromechanical flow divider.
Downstream of the infeed mechanism 4 of the cathodes, in this preferred embodiment of the invention, there is the first transfer mechanism 8.1 for transferring the same to the treatment mechanism. This first transfer mechanism 8.1 is formed by an aerial cable conveyor. Its purpose is to move the cathodes 5 from the alignment of the infeed mechanism 4 to the alignment of the stripping head.
The treatment mechanism of the first level, which is shown in figure 1, in this preferred embodiment of the invention, has on each one of the two stripping frames 7, cathode washing means, formed by a series of water manifolds with spray nozzles fastened to the stripping head.
In addition, in this preferred embodiment of the invention, both stripping frames 7 of the treatment mechanism respectively comprise first advance means of the cathodes 5 along the stripping head, formed in each case by a walking beam mechanism actuated hydraulically that has an anti-sway system.
In this preferred embodiment of the invention, the treatment mechanism comprises a guided blade system 6 for each one of the stripping frames 7 of the cathodes, wherein said blade system is secured to the stripping head. The purpose of the stripping frames 7 is to house the mechanisms responsible for completely separating the aluminum cathode and the zinc sheet, causing the latter to fall towards the lower level of the machine.
As shown in figure 1, in this preferred embodiment of the invention, before the stripping frames 7, the treatment mechanism comprises pre-stripping means 14 for each stripping frame 7 formed by a robot with a blade for each side of the cathode. The aim of these pre-stripping means 14 is to achieve an initial detachment of a small area of zinc throughout the upper portion of the cathode, without breaking the zinc sheet or damaging the surface of the cathode.
The robot equipped with the blade, in addition to being capable of carrying out the pre-stripping by means of said blades each acting on each face of the cathode, in the event that it detects difficulties in the pre-stripping, a rejection order is generated for said cathode and the robot is able to remove it.
After the cathodes have passed through the treatment mechanism, they are deposited on the second transfer mechanism 8.2, which in this preferred embodiment of the invention is formed by an aerial twin cable conveyor.
As shown in figure 1, in this preferred embodiment of the invention, the cathodes are transferred by means of said second transfer means 8.2 to a cathode scrubbing frame 15. Said scrubbing frame 15 is formed by two scrubbing mechanisms, one for each one of the simultaneously processed cathodes.
Each scrubbing mechanism fastens a scrubbing device and second advance means responsible for taking each cathode from the second transfer mechanism 8.2 through the scrubbing frame and to the outfeed mechanism 9, wherein said second advance means are formed by a walking beam.
In this preferred embodiment of the invention, said scrubbing device comprises a lifting mechanism formed by a mobile trolley guided by means of vertical rails, a sub-assembly of brushes fixed to connecting rods and, an irrigation system formed by a series of manifolds provided with spray nozzles.
As may be seen in figures 3 and 4, according to this preferred embodiment of the invention, the sheet reception system 10 of the second level 2 comprises a damping system of said sheets formed by a hatch actuated by means of pneumatic bellows and a sheet accompanying system.
According to this preferred embodiment of the invention, the sheet removal station 12 comprises a fixed reception frame, a reception robot and a guide device.
The embodiment described only constitutes one example of the present invention, and therefore, the specific details, terms and sentences used in the present specification must not be considered as limiting, but rather they must only be understood as a basis for the claims and as a representative basis that provides a comprehensible description as well as sufficient information in order for a person skilled in the art to apply the present invention.
Significant improvements with respect to the state of the art are achieved with the cathode stripping machine presented herein.
As such, a machine that is capable of acting on two cathodes at the same time is achieved, which means that in the same period of time, the number of cathodes that undergo the stripping is much greater than in earlier machines, significantly increasing the productivity thereof.
It is a fully organized machine which includes the actions the must be carried out with the cathodes. In this way, all the possible actions that must be carried out on the cathodes are mechanized.
As such, the labor of any phase of the process carried out by the machine is eliminated.

Claims

A cathode stripping machine (3) having a metal deposit in the form of a sheet on each one of the two opposite faces thereof, characterized in that it comprises
- a first operating level (1) and a second reception level (2) located below the first level;

- wherein the first level (1) comprises an infeed mechanism (4) of the cathodes in the machine, a first transfer mechanism (8.1) for transferring said cathodes (5) inside the machine, a treatment mechanism with a stripping head having two stripping frames (7), each acting on one cathode (5) simultaneously, a second transfer mechanism (8.2) for transferring the cathodes, and an outfeed mechanism (9) of the cathodes without sheets, and;

- wherein the second level (2) comprises for each of the two resulting sheets, a sheet reception system (10), a conveyor belt (11), and a sheet removal station (12), as well as a shared collection and weighing table (13) with rollers for both sheets.
Cathode stripping machine (3), according to claim 1, characterized in that the cathode (5) infeed mechanism (4) of the first level (1) comprises a parallel beam system, where a first beam is fixed and second beam is walking, the movement of which in a vertical direction is caused by a hydraulically actuated pivoting pusher assembly and the movement in a horizontal direction is generated by a synchronized double hydraulic cylinder assembly between them by means of a hydromechanical flow divider.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that the first transfer mechanism (8.1) for transferring the cathodes to the treatment mechanism is formed by an aerial chain conveyor and the second transfer mechanism (8.2) for transferring the cathodes is formed by an aerial twin cable conveyor.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that each stripping frame (7) of the treatment mechanism of the first level (1) comprises cathode scrubbing means, formed by a series of water manifolds with spray nozzles fastened to the stripping head.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that each stripping frame (7) of the treatment mechanism of the first level (1) comprises first advance means of the cathodes (5) along the stripping head, formed in both cases by a hydraulically-actuated walking beam mechanism that has an anti-sway system.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that the treatment mechanism comprises a guided blade system (6) for each one of the stripping frames (7) of the cathodes, wherein said blade system (6) is fastened to the stripping head.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that the treatment mechanism comprises pre-stripping means (14) for each stripping frame (7) formed by a robot with a blade for each side of the cathode.
Cathode stripping machine (3), according to claim 7, characterized in that the treatment mechanism comprises pre-stripping starting means that have a frame with movable cutting means, suitable for checking the level of adhesion between the cathode (5) and the sheet thereon.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that the first operating level (1) comprises a scrubbing frame (15) located downstream from the second transfer mechanism (8.2) and formed by two scrubbing mechanisms, one for each one of the cathodes (5) processed simultaneously, wherein each scrubbing mechanism fastens a scrubbing device and second advance means responsible for taking each cathode (5) from the second transfer mechanism (8.2) through the scrubbing frame (15) and to the outfeed mechanism (9), wherein these second advance means are formed by a walking beam.
Cathode stripping machine (3), according to claim 9, characterized in that, the scrubbing device comprises a lifting mechanism formed by a mobile trolley guided by means of vertical rails, a sub-assembly of brushes fixed to connecting rods, and an irrigation system formed by a series of manifolds provided with spray nozzles.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that the sheet reception system (10) of the second level (2) comprises a damping system of said sheets formed by a hatch actuated by means of pneumatic bellows and a sheet accompanying system.
Cathode stripping machine (3), according to claim 11, characterized in that the sheet reception system (10) comprises two pairs of wheels downstream of the damping system actuated by means of electric geared motors in order to control the drop speed of the sheets.
Cathode stripping machine (3), according to any of the preceding claims, characterized in that the sheet removal station (12) comprises a fixed reception frame, a reception robot and a guide device.