Laser curing method for card wire

Abstract

The invention relates to a method for laser beam hardening of a section A of a card wire 10, whereby the card wire 10 moves in a conveying direction through a working space 26. In the working space 26 an inert gas atmosphere is created by continuously or discontinuously introducing an inert gas G. In the working space 26 a laser beam area 27 is formed in which the section A of the card wire 10 to be hardened moves. This heats the section A to be hardened. After leaving the laser beam area 27 the section A to be hardened is cooled and hardened by running this temperature profile. Hardening in an inert gas atmosphere in the working space 26 avoids the formation of an oxide layer (scaling) and a tempered color.

Description

Technical Field

[0001] The present invention relates to a laser hardening method for a hardening target section of a card wire.

Background Art

[0002] The laser hardening method is known, for example, from Patent Document 1. In that case, a laser beam is directed through an opening into a working space, and a card wire moves in a transport direction through the working space. The card wire is preheated by a gas burner in the transport direction in front of the working space. Behind the working space in the transport direction, the card wire is cooled by a spray nozzle. The inside of the working space is spherical, and the laser light reflected from the card wire can be reflected back from the inside of the working space to the card wire. In this way, laser light can be directed at the card wire from two opposing side surfaces.

[0003] The laser hardening method of a card wire is also described in Patent Document 2.

[0004] Patent Document 3 describes the hardening of a card wire by induction heating and subsequent cooling by a cooling medium. This document states that laser hardening lacks superiority because local overheating may occur due to the energy of the laser beam. The induction heating of a card wire is also known from Patent Document 4.

[0005] Patent Document 5 describes a hardening method of a workpiece or tool such as a belt by an electron beam, and the electron beam energy is adapted to the shape and / or position of the hardening target section.

[0006] The use of a laser for laser beam cutting is known from Patent Document 6. Thereby, for example, the contour of a card wire can be cut from a workpiece.

[0007] The card wire has a base around which the card wire is wound onto a roller. The teeth have a roughly triangular contour and protrude from the base. In the direction of extension of the card wire or base, two directly adjacent teeth are separated from each other by a gap.

[0008] During carding, the fabric fibers are drawn out by the carding wire wound on the roller and directed circumferentially around the roller in the gaps between adjacent windings of the carding wire. This configures the teeth of the carding wire to draw out the fabric fibers and hold them until they are released. Therefore, it is desirable to provide these teeth with sufficient hardness to prevent excessive wear due to friction with the fabric fibers. The base of the carding wire needs to be elastic, as it must be wound onto the roller in sequence. Therefore, during the manufacture of all-steel carding wire for needle cloth, it is desirable for the carding wire to have different hardnesses in different regions.

[0009] Therefore, at least the hardening target section of each tooth of the card wire must be hardened, while the base has a lower hardness compared to the hardening target section. This creates a transition region between the already hardened and unhardened parts. In the transition region, the hardness of the card wire is not precisely defined, which can be a drawback for the card wire or each tooth of the card wire. Another disadvantage is that a metal oxide layer may form due to heating (scaling). Subsequently, it is generally necessary to remove the ion oxide layer again in a further process. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] U.S. Patent No. 4924062 [Patent Document 2] Swiss Patent No. 670455 [Patent Document 3] German Patent Application Publication No. 102014106574 [Patent Document 4] Japanese Patent No. 2909774 [Patent Document 5] German Patent No. 2018793 [Patent Document 6] German Patent Application Publication No. 102006030418 [Overview of the project] [Problems that the invention aims to solve]

[0011] Therefore, the object of the present invention is to provide a method for efficiently curing card wires using a space-saving device while avoiding scale formation. [Means for solving the problem]

[0012] This objective is achieved by a method having the features described in claim 1.

[0013] In this invention, a laser is used to harden a card wire in the hardening target section of the card wire. The card wire has a continuous base with protruding teeth. If the base extends linearly in the direction of extension, the teeth are oriented parallel to a common plane and arranged in a row in the direction of extension. This method includes the following steps:

[0014] In the workspace, at least one laser beam region is formed on at least one work surface. Preferably, exactly one laser beam region is formed within one work surface, or a first laser beam region is formed within a first work surface and a second laser beam region is formed within a second work surface. This ensures that the work surfaces are spaced apart from each other. The laser beam region can be formed by the cross-section of a continuous laser beam. The contour of the laser beam region may vary, for example, it can be polygonal, particularly rectangular. The laser beam region has an advantage in including at least one, preferably four, linearly extending outer edges. At each linear outer edge, the intensity of the laser light or the energy density of the laser beam region changes abruptly. The rate of change m represents the gradient of the intensity of the laser light at the outer edge of the laser beam region and can be defined, for example, as follows:

[0015]

number

[0016] The rate of change is preferably greater than 5, particularly preferably greater than 7, and even more preferably greater than 8.

[0017] An inert gas is introduced into the working space. The introduction of this inert gas can be carried out continuously or discontinuously. In this way, an inert gas atmosphere can be created within the working space. For example, nitrogen and / or argon and / or other noble gases can be used as the inert gas. By doing so, an inert and / or low chemically reactive atmosphere is created in the working space.

[0018] The card wire is conveyed in the conveying direction, particularly in the extending direction of the card wire into the working space. Therefore, it is preferable that the curing target section of each tooth of the card wire is oriented obliquely or orthogonally to the emission direction of the laser beam within the working space. The card wire is conveyed such that each curing target section moves along at least one laser beam region or through at least one laser beam region. Each curing target section has at least one outer surface that moves during the movement of the curing target section through the assigned at least one laser beam region along each working surface. For example, one single laser beam region can be formed within one single working surface, and the outer surface of each curing target section moves along the working surface through the laser beam region. It is also possible to form two laser beam regions on two working surfaces that are arranged parallel to each other and separated in a direction orthogonal to the conveying direction corresponding to the thickness of the curing target section. By doing so, the two opposing outer surfaces of each curing target section can be moved along one of the two working surfaces respectively via the assigned laser beam regions. Therefore, each curing target section can be heated from one side by a laser beam region or from both opposing sides by two laser beam regions.

[0019] While the area to be hardened is moving through at least one laser beam area, it is heated. Due to the conveying movement of the card wire, the area to be hardened moves away through at least one laser beam area, so that no additional energy or heat is introduced into the area to be hardened. Due to the heat conduction of the material of the card wire and the heat conduction between the card wire and the surrounding atmosphere in the working space, the area to be heated is rapidly cooled, thus improving the hardness. A gas flow is generated by the supply of an inert gas, and an additional cooling effect can be obtained as an option. In this case, the inert gas can be continuously introduced into the working space. The supply of a separate additional cooling medium is not necessary in all aspects. The heating and cooling of each area to be hardened of the card wire are completely carried out within the working space.

[0020] Therefore, the introduction and heating of energy for each area to be hardened by the laser beam area can be carried out in a small area. Since the heating and cooling are carried out in a very short period, the risk of scaling has already been reduced. However, despite this short-term hardening, it shows that the formation of the burnt raw color and / or scaling may occur. According to the present invention, for this reason, an inert gas is continuously or discontinuously introduced into the interior of the working space, so that a low-reactivity or inert atmosphere is created. By doing so, the laser hardening is further improved, and the post-treatment of the hardened area of the card wire can be omitted.

[0021] For the generation of laser light or a laser beam, a laser beam source such as a diode laser or a gas laser is used, for example. The wavelength of the laser light may be at least 650 nm, for example, in the range of 800 nm - 1400 nm, and in one aspect, the light wavelength is about 1000 nm.

[0022] It is preferable that the card wire moves continuously without stopping in the transport direction. Movement in the transport direction can be performed at a constant speed. The speed at which the card wire moves in the transport direction can be at least 10 m / min or 20 m / min, for example, 40 m / min-50 m / min, and the speed can be adjusted according to the dimensions of the teeth in the transport direction. Since the speed of the card wire during movement in the transport direction is constant, the period over which each curing target section moves through at least one laser beam area is also constant.

[0023] It is advantageous if at least one characteristic of the laser beam region is time-invariant, for example, the contour of the laser beam region and / or the intensity of the laser light during the laser's ON period and / or the beam impulse frequency, when the laser beam region is formed by a laser beam impulse. In one embodiment, the laser beam region is not switched on or off, and the energy density of the laser light does not change in a time-dependent manner within the range of the laser beam region (e.g., when the laser beam impulse frequency is zero). It is preferable that the spatial extension of the laser beam region and the position of the laser beam region in the working space are constant.

[0024] In a preferred embodiment, at least one laser beam region may have a non-circular contour. The length direction of the at least one laser beam region is in the transport direction, and the width direction is perpendicular to the transport direction, on the assigned work surface. The length and width are particularly different, with the width being shorter than the length. The length of the at least one laser beam region can be in the range of a minimum of 10 mm and a maximum of 100 mm, preferably 15 mm to 70 mm, and more preferably 25 mm or 30 mm to 40 mm. For example, the length of the laser beam region is 32 mm to 35 mm. The width of the laser beam region can be selected according to the height of the hardening section for each tooth, and in one embodiment can be at least 0.5 mm or 1.0 mm and / or a maximum of 2.0 mm or 3.0 mm.

[0025] In a preferred embodiment, each laser beam region can be formed by a beamforming optical system that converts an incident laser beam into an exit laser beam. The exit laser beam has a different cross-section from the incident laser beam. The exit laser beam forms a laser beam region on an assigned work surface. If a first laser beam region is to be formed on a first work surface and a second laser beam region on a second work surface, two separate beamforming optical systems can be used for this purpose. The beamforming optical system may include, for example, lenses, particularly free-form lenses similar to Powell lenses. In addition to such lenses, the beamforming optical system may include additional optical contraction and / or optical refraction and / or optical reflection components.

[0026] A further advantage is obtained if, within the laser beam region, the laser light passing through the laser beam region without colliding with the section to be cured is at least partially received by the beam dump. As the card wire moves in the transport direction, for example, the laser light passes through the laser beam region in a region where there is a gap between two adjacent teeth of the card wire. This laser light can be at least partially captured by the beam dump. For this reason, the beam dump can be positioned on the opposite side of the beamforming optical system, for example, with the work surface located between the beamforming optical system and the beam dump.

[0027] The beam dump can preferably be cooled by a cooling medium, such as water and / or air. Within the beam dump, at least one cooling channel through which the cooling medium flows can be extended for this purpose. Additionally or alternatively, the cooling medium can be directed to the beam dump from the outside.

[0028] In one embodiment, the beam dump may include at least one incident surface oriented obliquely to the direction of propagation of the laser light passing through at least one laser beam region. In this way, the energy density of the laser light on the incident surface is lower than the energy density in the laser beam region. The energy density of the laser light can be reduced so that heating on the incident surface is not important for the beam dump, and the heat introduced thereby can be dissipated, preferably by active cooling with a cooling medium.

[0029] The duration for which laser light is applied to each point of the section to be cured in at least one laser beam region may be a maximum of 150 ms or a maximum of 100 ms. Preferably, the application duration can be in the range of 30 milliseconds to 90 milliseconds, and more preferably in the range of 50 milliseconds to 70 milliseconds. In one embodiment, the application duration is approximately 60 milliseconds. The application duration can be adjusted, for example, according to the length of at least one laser beam region in the transport speed and / or transport direction of the card wire.

[0030] Burn the card wire before it enters at least one laser beam region. raw It is preferable to bake. raw The coating can be limited to the base of the card wire, or at least cover it. Alternatively, the coating can be applied to the entire card wire. raw It can also be treated with a baking process. raw This process includes warming up from the initial temperature to the holding temperature, complete heating at the holding temperature, and cooling to a target temperature that corresponds to the initial temperature of the card wire before warming up. The target temperature and / or initial temperature may be, for example, the ambient temperature.

[0031] Furthermore, it is advantageous if the method includes a step of cleaning the card wire before transitioning to at least one laser beam region. Cleaning is an optional step. rawThis may be done before the process. Cleaning is carried out, in particular, without direct contact between the cleaning tool and the card wire, for example, by spraying the cleaning solution onto the card wire. Water may be used as the cleaning solution.

[0032] It is advantageous if the warm-up of at least one curing section is measured, for example, by a pyrometer. In this way, the energy density of the laser light in at least one laser beam region can be adjusted so that a desired temperature is achieved in the curing section of the card wire. By measuring the temperature within the curing section, closed-loop control or adjustment of the laser energy, and therefore the energy density of the laser light in at least one laser beam region, can also be achieved.

[0033] Superior embodiments of the present invention are derived from the dependent claims, the detailed description of the invention, and the drawings. Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The drawings are as follows. [Brief explanation of the drawing]

[0034] [Figure 1] This is a partial schematic perspective view of an example of card wire. [Figure 2] Figure 1 is a partial schematic side view of the card wire. [Figure 3] This is a cross-sectional view showing a plane perpendicular to the extension direction of the card wire at the cutting line III-III in Figure 2. [Figure 4] Figures 1 to 3 are basic schematic diagrams illustrating the progression of hardness in already hardened teeth using card wire. [Figure 5] This is a basic schematic diagram of a curing apparatus and curing method for card wire, viewed from the direction of transport. [Figure 6] This is a schematic diagram of the apparatus and method shown in Figure 5, viewed from a side perpendicular to the conveying direction. [Figure 7] This is a basic diagram of the laser beam region of the present invention, where the length direction is the transport direction and the width direction is perpendicular to the transport direction. [Figure 8]This is a very schematic diagram of a modified example of a laser curing apparatus and laser curing method for card wire. [Modes for carrying out the invention]

[0035] The present invention relates to laser curing of a card wire 10, which is schematically shown in Figures 1 to 3. The card wire 10 comprises a base 11 extending in the longitudinal direction L. The cross-section of the base 11 may be polygonal, for example, rectangular. In the width direction B, a plurality of teeth 12 protrude from the base 11, alternately arranged in the longitudinal direction L. There is a gap 13 between each pair of directly adjacent teeth 12 in the longitudinal direction L. Each tooth 12 has a substantially triangular profile with a corner 14 positioned away from the base 11 in the width direction B. The corner 14 is formed by two edges 15, 16 that define the profile of the tooth 12. In this embodiment, one first edge 15 extends substantially in the width direction B, and the other second edge 16 extends obliquely with respect to the width direction B.

[0036] In the depth direction T, which is perpendicular to the width direction B and the longitudinal direction L, the base 11 has thickness or strength in a section that is at least longer than the thickness of the teeth 12. Thus, in the embodiment, a projection is formed on the base 11 which has a longitudinal surface 17 oriented perpendicular to the width direction B. Each tooth 12 has a first outer surface 18 and a second outer surface 19 facing the first outer surface 18. The two outer surfaces 18 and 19 are spaced apart from each other in the depth direction T according to the thickness of the tooth 12. The two outer surfaces 18 and 19 can be arranged parallel to each other. In the embodiment, the second outer surface 19 extends substantially perpendicular to the depth direction T, while the first outer surface 18 is oriented to be oblique to the depth direction T and the second outer surface 19. The first outer surface 18 extends along a first surface E1, and the second outer surface 19 extends along a second surface E2 (Figure 3).

[0037] The hardening target section A is adjacent to the corner portion 14 of each tooth. In this section, each tooth 12 is hardened. The hardening target section A is positioned at a distance from the projection of the base portion 11 adjacent to the longitudinal surface 17. After the hardening target section A is hardened by the laser hardening of the present invention, the transition region Z is adjacent to the hardening target section A where the hardness decreases continuously toward the base portion 11. In the width direction B, the dimensions of the transition region Z after laser hardening by the method of the present invention are in the range of less than 0.3 mm, preferably less than 0.2 mm.

[0038] To cure section A, energy is introduced into section A and heated. Heating of section A is performed by radiation of laser light from a laser beam. Examples of the laser curing apparatus and laser curing method are shown in schematic diagrams of their configurations in Figures 5 and 6, respectively.

[0039] For laser curing, a workspace 26 is defined within the housing 25. In this workspace 26, the card wire 10 is processed in the curing target section A, and in particular, laser curing is performed. In the embodiment, the card wire 10 is moved through the workspace 26 in the transport direction F by a transport device (not shown). The transport direction F can be, for example, the horizontal direction. When the card wire 10 is transported in the transport direction F, it is preferable that the card wire 10 is oriented so that its longitudinal direction L faces the transport direction. It is preferable that the width direction B of the card wire 10 is oriented parallel to the transverse direction Q of the workspace 26, which is perpendicular to the transport direction F. The transport direction F and the transverse direction Q can form a horizontally extending surface. The card wire 10 can move within the workspace in a so-called lateral position.

[0040] In this preferred embodiment, the card wire 10 moves continuously through the working space 26, thereby being processed, particularly cured. The speed at which the card wire 10 moves in the conveying direction F is preferably constant, and in this embodiment, it is at least 10 m / min or at least 20 m / min, for example, 40 m / min-50 m / min, where the speed depends on the dimensions of the teeth 12, with larger teeth 12 resulting in a lower speed.

[0041] In the workspace, at least one laser beam region 27 is formed, and in the embodiments relating to Figures 5 and 6, exactly one laser beam region 27 is formed. For this purpose, the apparatus includes a laser beam source 28 that emits a laser beam 29. The emitted laser beam 29 can be supplied directly to the beamforming optical system 31 as an incident laser beam 30, or alternatively, indirectly through one or more optical elements. The optical elements can redirect and / or refract and / or diffract and / or reflect the laser beam and then supply it to the beamforming optical system 31 as an incident laser beam 30.

[0042] The laser light of the laser beam 29 generated by the laser beam source 28 preferably includes a wavelength of at least 650 nm or at least 800 nm, for example, in the range of 800 nm to 1400 nm, and in examples, a wavelength of about 1000 nm.

[0043] The beamforming optical system 31 is configured to form an incident laser beam 30 and an exit laser beam 32 therefrom, and has a defined cross section on the working surface. For this purpose, the beamforming optical system 31 may include one or more optical components such as lenses, particularly free-form surface lenses 33.

[0044] On the work surface inside the work space 26, the emitted laser beam 32 forms a laser beam region 27. In the embodiment shown in Figures 5 and 6, the work surface extends or is inclined in the transverse direction Q within the work space 26 in the transport direction F and the transverse direction Q, and the first surface E1 of the first outer surface 18 present in the work space is substantially positioned within the work surface. The emitted laser beam 32 has specified dimensions and energy density in its laser beam region 27 positioned within the work surface. As very schematically shown in Figure 7, the laser beam region 27 has a length x in the transport direction F and a width y along the work surface, perpendicular to the transport direction F, or in the transverse direction Q. The length x is different from the width y, and is particularly preferably longer than the width y. In the embodiment, the length x can be a minimum of 10 mm and a maximum of 100 mm, preferably 15 mm to 70 mm, more preferably 25 mm or 30 mm to 40 mm, and particularly 32 mm to 35 mm. The width y of the laser beam area 27 can be adjusted to match the dimensions of the hardening target section A of the tooth 12, for example, to a minimum of 0.5 mm or a range of 1.0 mm to 2.0 mm or 3.0 mm.

[0045] According to the embodiment, at least one laser beam region 27 has a rectangular or otherwise polygonal contour. At least it has a linear outer edge that is oriented parallel to the transport direction F and limits at least one laser beam region 27 toward the base 11. At each linear outer edge, the intensity of the laser light or the energy density of at least one laser beam region 27 changes abruptly. The rate of change m represents the gradient of the intensity of the laser light at the outer edge of the laser beam region, and is, for example, as follows:

[0046]

number

[0047] The rate of change is preferably greater than 5, particularly preferably greater than 7, and even more preferably greater than 8.

[0048] A low-reactivity or inert gas atmosphere is created in the workspace 26, and a metal oxide layer (scale) is formed by laser curing and burning. raw To avoid the generation of discoloration, an inert gas G is introduced into the working space 26. For this purpose, the housing 25 may be provided with at least one gas connection 37 for supplying the inert gas G. The inert gas G can be introduced into the working space 26 continuously or discontinuously.

[0049] The inert gas G is introduced into the workspace 26 adjacent to the beamforming optical system 31, and preferably flows obliquely or perpendicular to the direction of travel of the emitted laser beam 32, for example, in the transverse direction Q and / or the transport direction F. In the embodiment, the inert gas G is introduced perpendicularly between the work surface or laser beam region 27 and the beamforming optical system 31. The flow of the inert gas G can protect the beamforming optical system 31 and can act as a sealing gas for so-called fumes and / or vapors generated during laser curing and / or other processing in the workspace 26. The inert gas G can remove fumes and / or vapors from the laser beam region 27. Thus, the inert gas G not only generates a low-reactivity or inert atmosphere in the workspace 26 according to the embodiment, but also protects the beamforming optical system 31 and / or maintains as uniform an energy density as possible in the laser beam region 27 on the surface of the card wire 10.

[0050] As the inert gas G, nitrogen, argon, or other noble gases, or any combination thereof, can be used.

[0051] For laser curing, the card wire 10 moves through the working space 26, and the curing section A of each tooth 12 then moves through the laser beam region 27. During this movement, the curing section A is heated in the laser beam region 27 and rapidly cooled after leaving the laser beam region 27, thus improving its hardness. This cooling is achieved by conduction of heat within the card wire 10 from the heated curing section toward the base 11. Additional cooling can be achieved by heat dissipation in the atmosphere within the working space 26. The gas flow brought about by the introduction of an inert gas G into the working space 26 can contribute to further cooling of the heated section.

[0052] As schematically shown in Figure 7, the laser beam region 27 is positioned so that only the hardening target section A of the tooth 12 moves through the laser beam region 27. Other sections of the card wire 10 that do not need to be hardened, particularly the base 11, are moved outside the laser beam region 27 through the working space 26.

[0053] In the embodiment, the application period during which the laser light of the emitted laser beam 32 in the laser beam region 27 acts on each point of the curing target section A passing through it is a maximum of 150 ms or a maximum of 100 ms. Preferably, the application period can be in the range of 30 milliseconds to 90 milliseconds, and more preferably in the range of 50 milliseconds to 70 milliseconds. In the embodiment, the application period is approximately 60 milliseconds.

[0054] After hardening of the hardening target section A of tooth 12, the hardness of tooth 12 progresses to basically the level schematically shown in Figure 4. The horizontal axis of the figure defines the distance d in the width direction B from the corner 14 of tooth 12. The vertical axis shows the hardness H based on the distance d. The hardness H after hardening is maximum and approximately constant in each hardening target section A. Hardness decreases in the transition region Z. Outside the hardened section A, the hardness H corresponds to the value of the unhardened material of the card wire 10. The dimension of the transition region Z in the width direction B is small, preferably less than 0.2 mm. The unhardened base 11 provides sufficient elasticity and deformability, and the card wire 10 can be wound onto a roller after hardening without problems, without cracking or other damage.

[0055] As shown in Figures 5 and 6, a beam dump 38 may exist behind the work surface or surface through which the card wire 10 travels in the work space 26, in the direction of the emitted laser beam 32's travel. The beam dump 38 is configured to capture at least partially the laser light of the emitted laser beam 32 as it passes through the laser beam region 27, particularly the gap 13 between the two teeth 12, without colliding with the card wire 10 (see also Figure 7). The beam dump 38 has at least one incident surface 39, in embodiments two incident surfaces 39, positioned obliquely to the direction of the laser light of the emitted laser beam 32's travel. The incident surfaces 39 can be arranged, for example, in a V-shape. The inclination of the incident surfaces 39 with respect to the direction of the laser light's travel expands the area in which the laser light collides with at least one incident surface 39 compared to the area of ​​the laser beam region 27. Therefore, the energy density of the laser light collides with at least one incident surface 39 is reduced. Thus, the absorption per unit area in the beam dump 38 is also sufficiently low.

[0056] In this embodiment, at least one incident surface 39 is realized by the outer surface of the heat sink 40. The heat sink 40, and therefore at least one incident surface 39, can be cooled by a cooling medium K, for example, air, water, or another fluid. For this purpose, at least one cooling channel 41 may exist inside the heat sink 40 in a manner that the cooling medium K flows through it. The cooling circuit of the cooling medium K is shown only in a very schematic manner in Figure 5.

[0057] Based on Figure 6, the possibility of any additional configurations for carrying out the method or for configuring the apparatus is shown. An additional station for processing the card wire 10 may be located inside the housing 25, preferably positioned in front of the laser beam area 27 in the direction of movement of the card wire 10. For example, it may be a cleaning station or a burning station. raw The cleaning station 42 is sufficient. The cleaning station 41 is configured to clean at least the curing target section A of the card wire 10. raw The station 42 burns at least the base 11 of the card wire 10 raw It is configured in such a way.

[0058] The cleaning station 41 can be configured to output a cleaning substance and spray it onto the curing target section A of the card wire 10 to remove dirt. Optionally, the card wire 10 can then be dried in the cleaning station 41, for example, by gas-powered blow drying.

[0059] Grill raw Station 42 burns at least the base 11 of the card wire 10 or the entire card wire 10. raw It is configured to do so. rawThe station 42 may be equipped with a heating device 43, a cooling device 44, and optionally a drying device 45. The heating device 43 is responsible for introducing at least heat to the base 11 of the card wire 10 and heating it to a holding temperature. Subsequently, the portion of the card wire 10 thus heated is cooled by the cooling device 44, for example, by spraying a cooling substance such as water. Subsequently, the card wire 10 can be dried by the drying device 45, for example, by blow drying using gas.

[0060] Washing and / or burning at washing station 41 raw Grilling at station 42 raw Subsequently, the section A to be cured is cured in the workspace by laser curing. In this embodiment, all of these processing steps are performed inside the workspace 26.

[0061] Figure 8 shows a further embodiment for laser curing of the curing target section A of the card wire 10 as a highly simplified schematic basic diagram. In this embodiment, two outgoing laser beams 32 are generated by two separate beamforming optical systems 31, each forming a laser beam region in the respective case, and in this embodiment, a first laser beam region 27a is formed on a first work surface and a second laser beam region 27b is formed on a second work surface located at a distance from it. The two work surfaces can be extended parallel to or inclined to each other and are oriented according to the embodiment, such that the first surface E1 of the curing target section A moves along the first work surface and the second surface E2 of the curing target section A moves along the second work surface. In this arrangement, the energy of the laser light can be introduced into the curing target section A of the card wire 10 from two opposing sides, namely the first outer surface 18 of the first laser beam region 27a and the second outer surface 19 of the second laser beam region 27b.

[0062] In the transport direction F, the laser beam regions 27a and 27b may be offset from each other, or they may alternately overlap at least partially.

[0063] As further shown in Figure 8, two separate beam dumps 38 can be provided for the two outgoing laser beams 32. Although the outgoing laser beams 32 are not oriented parallel to a common axis, their directions of propagation are oriented at angles of less than 180° to each other.

[0064] To generate two output laser beams 32 using two beamforming optical systems 31, the output laser beam 29 of a common laser beam source 28 can be used. Optionally, two separate laser beam sources 28 can be used.

[0065] The heating of at least one curing target section A moving through the assigned laser beam region 27 can be monitored. For example, a pyrometer 46 can be used for this purpose, as schematically shown in Figure 5. The pyrometer 46 can determine the thermal radiation W generated from the heated portion of the card wire 10 in at least one curing target section A. Thus, the pyrometer 46 can be used to check whether sufficient energy has been injected into at least one curing target section A. Where applicable, the adjustment of the laser beam source 28 can be modified to adapt the energy injection.

[0066] This invention relates to a laser beam curing method for a curing target section A of a card wire 10. The card wire 10 moves in the transport direction through a working space 26. An inert gas atmosphere is created within the working space 26 by continuously or discontinuously introducing an inert gas G. A laser beam region 27 is formed within the working space 26, and the curing target section A of the card wire 10 moves through it. This heats the curing target section A. After exiting the laser beam region 27, the curing target section A is cooled and cured by proceeding through this temperature profile. Curing in the inert gas atmosphere within the working space 26 prevents the formation of an oxide layer (scaling) and burning. raw The color is avoided. [Explanation of Symbols]

[0067] 10 card wires 11 Base 12 teeth 13 Gap 14 corners 15 The First Connection 16. The Second Connection 17 Longitudinal surface 18 First outer surface 1 19. Second outer surface 25 Housing 26. Workspace 27 Laser beam region 27a First laser beam region 27b Second laser beam region 28 Laser beam source 29 Laser beam 30 Incident laser beam 31 Beamforming Optics 32 Emitting laser beam 33 Free-form surface lenses 37 Gas connection 38 Beam Dump 39 Contact surface 40 Heatsink 41 Washing Station 42 Baked raw station 43 Heating device 44 Cooling device 45 Drying equipment 46. ​​High-temperature thermometer A section to be hardened B Width direction d distance E1 First side E2 Second side F Conveying direction G Inert gas H Hardness K cooling medium L (Length direction) Q: Transverse direction T depth direction W Thermal radiation x Length of the laser beam region y: width of the laser beam region Z transition area

Claims

1. A laser curing method for a card wire (10) comprising a base (11) and a plurality of teeth (12) protruding from the base, A step of forming at least one laser beam region (27) inside the working space (26), A step of supplying an inert gas (G) to the aforementioned workspace (26), The process involves transporting the card wire (10) in the transport direction (F) to the work space (26), so that the hardening target section (A) of each tooth (12) moves through the at least one laser beam region (27), so that at least one outer surface (18, 19) of each hardening target section (A) moves through the at least one laser beam region (27), and the hardening target section (A) is heated. A step of cooling the section to be hardened (A), A laser curing method that includes the following features.

2. The method according to claim 1, characterized in that the card wire (10) moves continuously in the transport direction (F) without stopping.

3. The method according to the 2, characterized in that the card wire (10) moves at a constant speed in the transport direction (F).

4. The method according to any one of claims 1 to 3, characterized in that the at least one laser beam region (27) has a non-circular contour having a length (x) in the transport direction (F) and a width (y) perpendicular to the transport direction (F), wherein the width (y) is particularly shorter than the length (x).

5. The method according to any one of claims 1 to 4, characterized in that the at least one laser beam region (27) includes at least one straight outer edge.

6. The method according to 5, characterized in that at least one straight outer edge of the laser beam region (27) is oriented parallel to the transport direction (F).

7. The method according to claim 5 or 6, characterized in that the intensity of the laser light changes abruptly at each linear outer edge of the laser beam region (27).

8. The method according to any one of claims 1 to 7, characterized in that the at least one laser beam region (27) is formed by at least one beamforming optical system (31) that converts an incident laser beam (30) into an outgoing laser beam (32), and so the outgoing laser beam forms at least one of the at least one laser beam region (27).

9. The method according to the 8th, characterized in that there is a beam dump (38) configured to capture at least a portion of the laser light of the emitted laser beam (32).

10. The method according to 9, characterized in that the beam dump (38) is cooled by a cooling medium (K).

11. The method according to 9 or 10, characterized in that the beam dump (38) comprises at least one incident surface (39) of the emitted laser beam (32) which is directed obliquely with respect to the direction of propagation of the laser light passing through the at least one laser beam region (27).

12. The method according to any one of claims 1 to 11, characterized in that the laser beam source (28) emits a laser beam (29) for forming the at least one laser beam region (27) having a wavelength of 900 nm to 1100 nm.

13. The method according to any one of claims 1 to 12, characterized in that the period for which laser light is applied to the laser beam region (A) in the at least one laser beam region (27) is 50 ms to 70 ms.

14. The method according to any one of claims 1 to 13, characterized in that the card wire (10) is annealed before entering the at least one laser beam region (27).

15. The method according to any one of claims 1 to 14, characterized in that the card wire (10) is cleaned before entering the at least one laser beam region (27).

16. The method according to any one of claims 1 to 15, characterized in that a first laser beam region (27a) and a second laser beam region (27b) located at a distance from each other are formed.

17. The method according to 16, characterized in that the first outer surface (18) of the hardening target section (A) moves through the first laser beam region (27a), and the second outer surface (19) of the hardening target section (A) opposite to the first outer surface (18) moves through the second laser beam region (27b).

18. The method according to any one of claims 1 to 17, characterized in that the heating of the hardening target section (A) is measured.

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