Method and device for cleaning the surface of a metal wire or strip

Abstract

The invention relates to a method for cleaning a surface of a metal wire (2) or a metal strip, in particular a surface of a metal wire (2) or a metal strip used as an intermediate electrode of a roll gap welder, the metal wire (2) or the metal strip is guided under tension in the longitudinal direction of the wire or strip along a plurality of stripping bodies (4) which are arranged at a distance in sequence in the longitudinal direction of the wire or strip, so that the wire segments or strip segments (5a-5g) which are located in each case between two successive stripping bodies (4) together form an arc-shaped wire segment. It has been confirmed that dense and reliable cleaning with a constant cleaning quality can thereby be achieved.

Description

Technical Field

[0001] The invention relates to a method for cleaning the surface of a metal wire or metal strip, a device for cleaning the surface of a metal wire or metal strip and a use of such a device according to the preambles of the independent claims. Background Art

[0002] In resistance roller seam welding machines for tinplate packaging, such as cans for food, copper wire is used as an intermediate electrode for keeping the electrode rollers clean by absorbing and conducting away the tin released from the tinplate during welding. In order to ensure good electrical contact between wire and electrode roller, it is important that the wire is free of dust and dirt. For cost reasons, the wire is used twice in such resistance roller seam welding machines, once for the first electrode roller and once for the second electrode roller.

[0003] Since the wire already has certain contamination in the delivery state, such as copper oxide, and copper dust forms when it is flattened for use as an intermediate electrode, it is advisable to clean the wire before the first use, but at least also before the second use. This is particularly true in the case of highly tinned tinplate (5 g / m2 to 12 g / m2), as is required in certain vegetable and fruit cans.

[0004] According to the prior art, the wire is drawn between two discs equipped with brushes and cleaned in this way. These discs have an unsatisfactory and inconsistent cleaning effect and wear out quickly. The discs must also be cleaned regularly from the copper dust that has accumulated therein. Furthermore, the desired cooling of the wire after flattening or after the first use of the wire is hardly possible with the discs equipped with brushes.

[0005] A device for cleaning strip copper wire is known from CH691668A5, in which the wire is guided via a guide roller with a guide groove and the outer surface of the wire contacts the cutting edge of a rotating knife disc. The disadvantage of this device is that there is only a point contact between the wire surface and the cutting edge of the knife disc, so that thorough cleaning is impossible from the beginning. Another disadvantage is that the material stripped from the wire enters the surrounding environment of the device in an uncontrolled manner. Another disadvantage of this device is that the wire can only be placed on the guide roller after the knife disc has been removed or moved away. Summary of the invention

[0006] The object is therefore to provide a technical solution which at least partially avoids the disadvantages of the prior art.

[0007] The object is achieved by the technical solutions of the independent patent claims.

[0008] Accordingly, a first aspect of the present invention relates to a method for cleaning the surface of a metal wire or metal strip. Preferably, the method is a method for cleaning the surface of a metal wire or metal strip used as an intermediate electrode of a roll seam welder.

[0009] According to the present invention, the metal wire or the metal strip is guided under tension in the longitudinal direction of the wire or the strip along a plurality of stripping bodies arranged at intervals in sequence in the longitudinal direction of the wire or the strip, so that the wire segments or strip segments respectively located between two consecutive stripping bodies together form an arcuate wire segment, which in particular has the shape of an arcuate polygon.

[0010] It has been shown that this allows intensive and reliable cleaning with a constant cleaning quality.

[0011] The stripping body is preferably provided on the outer side of a common carrier in a freely accessible manner, so that the metal wire or metal strip can be placed on the stripping body by hand and preferably also so that no tools or components have to be moved or disassembled for this purpose. This allows simple and uncomplicated handling during maintenance work.

[0012] In a preferred variant of the above-described embodiment of the method, a carrier is used, which has an interior space and in which the spacings between the stripping bodies form channels, via which the interior space is connected to the surroundings of the carrier. In this method variant, while the metal wire or the metal strip is guided along the stripping bodies in order to clean their surface, a negative pressure is applied to the interior space, whereby dirt stripped off from the stripping bodies is sucked off via the interior space of the carrier. Thus, with this variant, it is possible to discharge the material stripped off from the wire in a controlled manner. The wire is also cooled by the air flow sucked in over the wire.

[0013] It is advantageous that the channel has a width corresponding to at least twice the width of the metal wire or the metal strip when viewed in the longitudinal direction of the wire or strip. This ensures that a sufficiently large inflow opening is formed between the wire and the boundary of the channel in order to generate an air flow suitable for carrying away the material stripped from the wire.

[0014] In another preferred embodiment of the method, guide elements, more precisely preferably guide pins, are arranged upstream or downstream of the stripping bodies arranged at intervals in succession, as seen in the longitudinal direction of the wire or strip, with the help of which the metal wire or the metal strip is guided transversely to its placement direction on the stripping body, so that the metal wire or the metal strip is guided via the stripping body without lateral movement.

[0015] In a method variant using a carrier body carrying the stripping body, it is preferred that the guide element is provided in the carrier body. As a result, the guide element can be provided in a simple manner in the immediate vicinity of the stripping body.

[0016] In a further preferred embodiment of the method according to the invention, the stripping bodies used are designed and the metal wire or the metal strip is guided through them in such a way that at each stripping body the metal wire or the metal strip first passes a stripping edge in order to strip dirt from its surface and then is guided along a contact surface of the stripping body in order to cool the metal wire or the metal strip by the stripping body. As a result, the wire can not only be cleaned during guidance through the stripping bodies but can also be actively cooled by the stripping bodies.

[0017] Advantageously, a ceramic stripping body or a stripping body made of hard metal is used in the method. Such stripping bodies can be purchased at low cost (for example in the form of cutting blades for metal cutting) and have a long service life.

[0018] The metal wire or metal strip cleaned according to the method according to the invention preferably consists of copper or a copper alloy.

[0019] In another preferred embodiment of the method, in a first step, a substantially round metal wire is flattened so that the metal wire has two parallel flat sides when viewed in cross section. Immediately after the flattening, in a second step, the wire is first guided with the first of the two flat sides under tension in the longitudinal direction of the wire or strip along a plurality of first stripping bodies arranged in sequence at intervals in the longitudinal direction of the wire or strip, so that the wire or strip sections located between two consecutive first stripping bodies together form an arcuate wire section, in particular, in the shape of an arcuate polygon. Immediately thereafter, the wire is guided with the other of the two flat sides under tension in the longitudinal direction of the wire or strip along a plurality of second stripping bodies arranged in sequence at intervals in the longitudinal direction of the wire or strip, so that the wire or strip sections located between two consecutive second stripping bodies together form an arcuate wire section, in particular, in the shape of an arcuate polygon.

[0020] The method is particularly well suited for providing and cleaning copper wire to be used as an intermediate electrode for a roll seam welding machine prior to use.

[0021] A second aspect of the invention relates to a device for cleaning the surface of a metal wire or metal strip, more precisely a metal wire or metal strip preferably used as or to be used as an intermediate electrode of a roll seam welder, which cleaning can preferably be carried out according to the method according to the first aspect of the invention.

[0022] The device includes a carrier having a plurality of stripping bodies, each of which is arranged in sequence at intervals so that the metal wire or metal strip to be cleaned can be guided along the stripping body under the action of tension in the longitudinal direction of the wire or strip, and the wire or strip sections respectively located between two consecutive stripping bodies together form an arcuate wire section, in particular having the shape of an arcuate polygon.

[0023] It has been shown that with such a device, intensive and reliable cleaning can be achieved with a constant cleaning quality.

[0024] The stripping body is preferably provided on the outer side of the common carrier so that it is freely accessible, so that the metal wire or the metal strip can be placed on the stripping body by hand, and preferably also so that no tools or components have to be moved or disassembled for this purpose. This allows simple and uncomplicated handling during maintenance work.

[0025] In a preferred variant of the above-mentioned embodiment of the device, the carrier has an interior space and the spacings between the stripping bodies form channels, via which the interior space is connected to the surroundings of the carrier. During the guidance of the metal wire or the metal strip along the stripping bodies for cleaning the surface of the metal wire or the metal strip, the interior space can be subjected to a negative pressure, so that dirt stripped off from the stripping bodies can be sucked away via the interior space of the carrier. Thus, with this variant, it is possible to discharge the material stripped off from the wire in a controlled manner. The wire can also be cooled by the air flow sucked over it.

[0026] In another preferred embodiment of the device, guide elements, more precisely preferably guide pins, are arranged upstream or downstream of the stripping bodies arranged at intervals in the longitudinal direction of the wire or strip, by means of which the metal wire or the metal strip can be guided transversely to its placement direction on the stripping body, in particular so that the metal wire or the metal strip is guided substantially centrally through the stripping body. This ensures that the wire contacts the stripping body at a point provided for this purpose and, in the case of the above-mentioned embodiment of the device, also ensures that inlet openings of substantially the same width are formed on both sides of the wire in order to generate an air flow suitable for transporting material stripped from the wire and cooling the wire.

[0027] It is preferred that the guide element is provided in the carrier body so that the guide element is arranged in a simple manner in the immediate vicinity of the stripping body.

[0028] In a further preferred embodiment of the device, the stripping bodies are designed and the metal wire or the metal strip can be guided through the stripping bodies in such a way that the metal wire or the metal strip first passes the stripping edge at each stripping body in order to strip dirt from its surface and then is guided along the contact surface of the stripping body in order to cool the metal wire or the metal strip by the stripping body. As a result, the wire can not only be cleaned during guidance through the stripping bodies but can also be actively cooled by the stripping bodies.

[0029] The stripping body of the device according to the invention is preferably made of hard metal or ceramic. Such a stripping body can be purchased at low cost (for example in the form of a blade for metal cutting) and has a long service life.

[0030] A third aspect of the invention relates to the use of the device according to the second aspect of the invention for cleaning metal wires or metal strips made of copper or copper alloys. The advantages of the invention are particularly evident in such applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Other advantages and applications of the present invention are apparent from the following description based on the accompanying drawings. In the accompanying drawings:

[0032] Figure 1 A perspective view showing an apparatus for cleaning the surface of a copper wire according to the present invention;

[0033] Figure 2 Show Figure 1 A longitudinal section of the equipment in FIG.

[0034] Figure 3 Show Figure 2 Details X; and

[0035] Figure 4 Shown in use Figure 1 Schematic diagram of the method according to the invention in the case of a device. DETAILED DESCRIPTION

[0036] Figure 1 A perspective view of a device 1 according to the invention for cleaning the surface of a metal wire 2 used as an intermediate electrode of a roll seam welding machine, the metal wire being made of copper, is shown. Figure 2 Show Figure 1 A longitudinal section of the equipment in FIG.

[0037] As from Figure 1and Figure 2 As can be seen from the overview of the device 1, the device 1 comprises a carrier body 3 made of aluminum or brass, which has a plurality of stripping bodies 4 made of hard metal, each of which is arranged at a distance from each other, so that the copper wire 2 to be cleaned can be guided along the stripping bodies 4 under the action of tension in the longitudinal direction of the wire, and the wire or strip sections 5a-5g (for the sake of clarity, only the stripping bodies 5a-5g) located between two consecutive stripping bodies are respectively Figure 1 ) together form an arcuate wire section having an arcuate polygonal shape.

[0038] The stripping body 4 is provided on the outer side of the carrier body 3 in a freely accessible manner, so that the copper wire 2 to be cleaned can be placed on the stripping body 4 by hand and without using tools.

[0039] The carrier 3 has an interior space 6, and the spacings between the stripping bodies 4 form channels 7, via which the interior space 6 is connected to the surroundings of the carrier 3. Here, the channel 7 has a width corresponding to at least twice the width of the wire 2, as seen in the longitudinal direction of the wire. While the copper wire 2 is guided along the stripping bodies 4 for cleaning the surface of the wire 2, the interior space 6 of the carrier 3 can be subjected to negative pressure (vacuum) in order to suck away dirt stripped off the stripping bodies 4 via the interior space 6 of the carrier 3.

[0040] As can also be seen, guide pins 8 are arranged in the carrier body 3 upstream or downstream of the stripping bodies 4 arranged at intervals in succession, as viewed in the longitudinal direction of the wire, by means of which the copper wire 2 is guided transversely to its placement direction on the stripping body 4 in such a way that it extends through the stripping body 4 without lateral displacement.

[0041] As shown Figure 2 Details of X Figure 3 As can be seen in conjunction, the stripping bodies 4 are designed and the copper wire 2 is guided through the stripping bodies 4 in such a way that the wire 2 first passes the stripping edge 9 at each stripping body 4 in order to strip dirt from its surface and then is guided along the contact surface 10 of the stripping body 4 in order to actively cool the wire 2 with the respective stripping body 4. It should be noted that the deflection of the wire 2 by the stripping body 4 is shown here in an exaggerated manner for the purpose of illustrating the described situation.

[0042] Figure 4 Shown in use Figure 1 In the case of an apparatus in the schematic diagram of the method according to the present invention, a copper wire 2a which is contaminated due to its use as an intermediate electrode in a first electrode roller of a roll seam welder is cleaned and supplied as a cleaned copper wire 2b which is reused as an intermediate electrode in a second electrode roller of the roll seam welder.

[0043] Here, the contaminated copper wire 2a is stretched along the longitudinal direction of the wire under the tension. Figure 1 The stripping bodies 4 arranged in sequence at intervals in the longitudinal direction of the wire are guided by the device 1 in the embodiment so that the wire sections 5a-5g (see also Figure 1 ) together form an arcuate wire segment having the shape of an arcuate polygon.

[0044] The dirt 14 removed in this process is sucked away by means of a vacuum pump 12 through the interior 6 of the carrier 3 and separated in a cyclone 11 , after which the sucked away air is released back into the surroundings via a filter 13 .

[0045] Although preferred embodiments of the invention are described in the present application, it is clearly stated that the invention is not limited to these preferred embodiments and can also be implemented in other ways within the scope of the following claims.

Claims

1. A method for cleaning the surface of a metal wire (2) or a metal strip, in particular a metal wire (2) or a metal strip used as an intermediate electrode of a roll seam welding machine, wherein the metal wire (2) or the metal strip is guided under tension in the longitudinal direction of the wire or strip along a plurality of stripping bodies (4) arranged in sequence and spaced apart in the longitudinal direction of the wire or strip, so that wire sections or strip sections (5a-5g) respectively located between two consecutive stripping bodies (4) together form an arcuate wire section.

2. The method according to claim 1, wherein: The arcuate wire section formed by the wire sections or strip sections (5a-5g) respectively located between two consecutive stripping bodies (4) has the shape of an arcuate polygon.

3. A method according to any one of the preceding claims, wherein: The stripping body (4) is provided on the outer side of the common carrier (3) in a freely accessible manner, so that the metal wire (2) or the metal strip can be placed onto the stripping body (4), in particular without tools.

4. The method according to claim 3, wherein: The carrier (3) has an internal space (6), and the spacing between the stripping bodies (4) forms a channel (7), the internal space (6) is connected to the surrounding environment of the carrier (3) via the channel; and when the metal wire (2) or the metal strip is guided along the stripping body (4) to clean the surface of the metal wire (2) or the metal strip, negative pressure is applied to the internal space (6) to suck away dirt stripped from the stripping body (4) via the internal space (6) of the carrier (3).

5. The method according to claim 4, wherein: The channel (7) has a width, viewed in the longitudinal direction of the wire or strip, which corresponds at least to twice the width of the metal wire (2) or the metal strip.

6. A method according to any one of the preceding claims, wherein: A guide element (8), in particular a guide pin (8), is arranged upstream or downstream of the stripping bodies (4) arranged at intervals in sequence, as viewed in the longitudinal direction of the wire or strip, by means of which the metal wire (2) or the metal strip is guided transversely to its placement direction on the stripping body (4), so that the metal wire (2) or the metal strip is guided via the stripping body (4) without lateral movement.

7. The method according to any one of claims 3 to 5 and according to claim 6, wherein: The guide element (8) is provided in the carrier (3).

8. A method according to any one of the preceding claims, wherein: The stripping bodies (4) are designed and the metal wire (2) or the metal strip is guided through the stripping bodies (4) in such a way that the metal wire (2) or the metal strip first passes a stripping edge (9) at each stripping body (4) in order to strip contaminants from its surface and then is guided along a contact surface (10) of the stripping body (4) in order to cool the metal wire (2) or the metal strip by means of the stripping body (4).

9. A method according to any one of the preceding claims, wherein: A ceramic stripping body or a stripping body (4) made of hard metal is used.

10. A method according to any one of the preceding claims, wherein: The metal wire (2) or the metal strip is made of copper or a copper alloy.

11. A method according to any one of the preceding claims, wherein: A substantially circular metal wire is flattened so that the metal wire has two parallel flat sides when viewed in cross section, and immediately after the flattening, the first of the two flat sides is first guided under the action of tension in the longitudinal direction of the wire or strip along a plurality of first stripping bodies which are arranged in sequence at intervals in the longitudinal direction of the wire or strip, so that the wire or strip sections respectively located between two consecutive first stripping bodies together form an arcuate wire section in particular having the shape of an arcuate polygon, and immediately thereafter, the other of the two flat sides is guided under the action of tension in the longitudinal direction of the wire or strip along a plurality of second stripping bodies which are arranged in sequence at intervals in the longitudinal direction of the wire or strip, so that the wire or strip sections respectively located between two consecutive second stripping bodies together form an arcuate wire section in particular having the shape of an arcuate polygon.

12. A device (1) for cleaning the surface of a metal wire (2) or a metal strip, in particular a metal wire (2) or a metal strip used as an intermediate electrode of a roll seam welding machine, in particular according to a method according to any of the preceding claims, the device comprising a carrier (3) having a plurality of stripping bodies (4), the stripping bodies being arranged in sequence at intervals so that the metal wire (2) or the metal strip to be cleaned can be guided along the stripping bodies (4) under tension in the longitudinal direction of the wire or strip, and the wire or strip sections (5a-5g) respectively located between two consecutive stripping bodies together form an arcuate wire section.

13. The device (1) according to claim 12, characterized in that The stripping bodies (4) are arranged in sequence at intervals so that the metal wire (2) or the metal strip to be cleaned can be guided along the stripping bodies (4) under the action of tension in the longitudinal direction of the wire or strip, and the arcuate wire segments formed by the wire or strip segments (5a-5g) respectively located between two consecutive stripping bodies have an arcuate polygonal shape.

14. The device (1) according to claim 12, wherein the stripping body (4) is provided on the outer side of the carrier (3) so as to be freely accessible, so that the metal wire (2) or the metal strip to be cleaned can be placed on the stripping body (4), in particular without tools.

15. The device (1) according to claim 14, wherein the carrier (3) has an inner space (6), and the distances between the stripping bodies (4) form channels (7), wherein the inner space (6) is connected to the surroundings of the carrier (3) via the channels, and during the guiding of the metal wire (2) or the metal strip along the stripping body (4) for cleaning the surface of the metal wire (2) or the metal strip, a negative pressure can be applied to the inner space (6) so as to suck away dirt (14) stripped off from the stripping body (4) via the inner space (6) of the carrier (3).

16. The device (1) according to any one of claims 12 to 15, wherein a guide element (8), in particular a guide pin (8), is arranged upstream or downstream of the stripping body (4) arranged at intervals in the longitudinal direction of the wire or strip, with the help of which the metal wire (2) or the metal strip can be guided transversely to its placement direction on the stripping body (4), in particular so that the metal wire (2) or the metal strip is guided via the stripping body (4) without lateral movement.

17. The device (1) according to any one of claims 14 to 15 and according to claim 16, the guide element (8) being provided in the carrier (3).

18. The device (1) according to any one of claims 12 to 17, wherein the stripping body (4) is designed and the metal wire (2) or the metal strip is guided through the stripping body (4) in such a way that the metal wire (2) or the metal strip first passes a stripping edge (9) at each stripping body (4) in order to strip dirt from its surface and then the metal wire or the metal strip is guided along a contact surface (10) of the stripping body (4) in order to cool the metal wire (2) or the metal strip by means of the stripping body (4).

19. The device (1) according to any one of claims 12 to 18, wherein the stripping body (4) is made of hard metal or ceramic.

20. Use of the device (1) according to any one of claims 12 to 19 for cleaning metal wires (2) or metal strips made of copper or a copper alloy.

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