Nozzle cooling element and laser processing device having nozzle cooling element

Abstract

The invention relates to a nozzle cooling element for a laser machining device for machining a workpiece by means of a machining laser beam. The nozzle cooling element has an interior space through which the processing laser beam and the process gas pass, the interior space having an inlet for the processing laser beam and an outlet for the processing laser beam. The nozzle cooling element has at least one channel surrounding the interior, into which channel a cooling fluid can flow in order to cool the nozzle cooling element. The channel has a first side wall, a second side wall, and a bottom connecting the first side wall with the second side wall.

Description

Technical Field

[0001] The present disclosure relates to a nozzle cooling element for a laser processing device. The present disclosure also relates to a laser processing device having a nozzle cooling element. Background Art

[0002] In a laser processing device or laser processing system for processing a workpiece, a laser beam emitted from a laser source or the end of a laser optical fiber is focused or bundled to the workpiece to be processed by means of beam guidance and focusing optics, which heats the workpiece locally to a melting temperature. Processing may, for example, include laser cutting, laser brazing or laser melting welding. The laser processing device may be a laser processing head, such as a laser cutting head or a laser welding head. During processing, a laser beam is emitted from the laser processing device. For this purpose, a nozzle or a nozzle element may be mounted on the laser processing head. The nozzle may, for example, be a cutting nozzle. When cutting a metal material or workpiece by means of a laser, a coaxially guided gas flow or gas flow of a process gas or a cutting gas is usually emitted from the nozzle together with the laser beam. The laser radiation and the process gas may be directed to the process area on the workpiece to be processed by the nozzle.

[0003] During the cutting process, the cutting gas fulfills different tasks. On the one hand, it assists in the discharge of the molten material from the cut by transmitting pressure and shear forces at the cutting front and on the cutting flanks. This function of the cutting gas is dominant when cutting stainless steel, because in this application scenario, an inert medium, usually nitrogen (N2), is used. When cutting mild steel, a reactive gas, usually oxygen (O2), is used. In this application scenario, the cutting gas assists the separation process in such a way that the iron can be converted into iron oxide. In this way, the reaction heat is introduced into the process in addition to the laser radiation. In addition, when cutting mild steel, the function of discharging the melt is also retained. The third task of the cutting gas is to prevent contamination of the last optical element in the laser processing head.

[0004] The laser processing device can be positioned relative to the workpiece to be processed by means of a distance adjustment, wherein the distance between the nozzle element and the workpiece can be measured capacitively, for example. For this purpose, an alternating measuring voltage is applied to the nozzle element. In order to be able to make electrical contact with the electrically conductive nozzle element in a suitable manner, it is useful to electrically insulate the nozzle element, which is mounted on the housing of the laser processing head, from the housing.

[0005] An insulating element for holding a nozzle element on a laser processing device is known, for example, from DE 90 04 335 U1.

[0006] The insulating part usually comprises a metal insert which is sunk into the ceramic insulating body and centered in a form-fitting manner. This form-fitting can cause problems if the metal insert is heated strongly. This occurs in particular when processing reflective materials with high laser powers. When the metal insert is heated strongly, it expands, which leads to tensile stresses on the ceramic insulating part, which can crack due to the overload.

[0007] Because ceramic materials generally have poor tensile strength and the dielectric properties and price of ceramic materials further restrict the materials that can be used, only limited thermal resistance of structures can be achieved in conventional manners.

[0008] In applications with a high focus position above the material to be processed or a low focus position below the material to be processed, high temperatures are generated due to the thermal radiation of the material to be processed, the edge radiation of the laser beam and back reflections.

[0009] Known systems for cooling nozzles or nozzle elements provide only inadequate cooling. For example, the cooling gas flow supplied via the cap nut is not sufficient to cool the nozzle sufficiently effectively in the combination of nozzle electrode and insulation due to the geometry and the active surface. Summary of the invention

[0010] The object of the disclosure is to provide a nozzle cooling element by means of which heat removal can be improved. Another object of the disclosure is to provide a nozzle cooling element that can be cooled better by a cooling fluid. Another object of the disclosure is to provide a nozzle cooling element that only slightly affects or does not affect the laser processing process when a cooling fluid flows through the nozzle cooling element. Another object of the disclosure is to provide a nozzle cooling element by means of which overheating of the fixing of the nozzle cooling element to the laser processing device is reduced or avoided.

[0011] At least one of the objects is achieved by the nozzle cooling element of the present application or by the laser processing device of the present application. The present application also proposes advantageous embodiments.

[0012] Disclosed is a nozzle cooling element for a laser processing device for processing a workpiece by means of a processing laser beam. The nozzle cooling element has an inner cavity for conducting the processing laser beam and a process gas. The inner cavity has an inlet for the processing laser beam and an outlet for the processing laser beam. The nozzle cooling element has at least one channel surrounding the inner cavity, into which a cooling fluid can flow in order to cool the nozzle cooling element. The channel has a first side wall, a second side wall and a bottom / bottom surface connecting the first side wall to the second side wall.

[0013] A laser processing device for processing a workpiece by means of a laser beam is also disclosed. The laser processing device comprises a laser processing device body and a nozzle cooling element connected to the laser processing device body. The nozzle cooling element may be any nozzle cooling element disclosed herein.

[0014] During the laser machining process, a cooling fluid flows through the nozzle cooling element. The cooling fluid is guided through channels in the nozzle cooling element, so that the heat transfer to the cooling fluid is improved. This reduces the heat transfer to the attachment of the nozzle element to the (usually ceramic) insulating part, so that the attachment heats up less and less tensile loads act on the insulating part. This also leads to improved durability of the insulating part. At the same time, the process gas flow guided out of the nozzle coaxially with the machining laser beam is not influenced or only slightly negatively influenced by the cooling fluid, so that the laser machining process can be run robustly.

[0015] The nozzle cooling element (also referred to as nozzle element) can consist of metal or include metal. The nozzle cooling element can be electrically conductive. A voltage, in particular an AC voltage, can be applied or has been applied to the nozzle cooling element. The nozzle cooling element can be part of a sensor arrangement which is provided for ascertaining the distance between the nozzle cooling element and the workpiece. For example, the nozzle cooling element can function as a nozzle electrode. The distance between the nozzle cooling element and the workpiece can be ascertained based on a capacitance measurement.

[0016] The laser processing device may be a laser processing head, and the laser processing device may be a laser cutting head, a laser welding head or a laser brazing head.

[0017] The processing of the workpiece can be a laser cutting process, a laser welding process or a laser brazing process.

[0018] The axis of the nozzle cooling element (also referred to as the inner cavity axis or central axis) can be defined by the inlet of the processing laser beam into the inner cavity of the nozzle cooling element and the outlet of the processing laser beam from the inner cavity of the nozzle cooling element. The axis can be defined by the center point of the inlet and the center point of the outlet. In this case, the inlet and the outlet can each be understood as surfaces that can extend parallel to each other. The axis can be the central axis of the inner cavity. Likewise, the axis can be determined by the optical path of the processing laser beam through the inner cavity. When the nozzle cooling element is installed in the laser processing device, the axis of the nozzle cooling element can be coaxial with the beam axis of the processing laser beam, in particular the processing laser beam that strikes the nozzle cooling element.

[0019] The radial direction can be oriented perpendicularly to the axis. The nozzle cooling element can be designed to be rotationally symmetrical with respect to the axis.

[0020] The outlet of the inner cavity can be understood as "down". The inlet of the inner cavity can be understood as "up". "Up" and "down" can be defined by the direction of gravity when the nozzle cooling element is installed in the laser processing device.

[0021] The inner space of the nozzle cooling element can be designed rotationally symmetrically about the axis. The cross section of the inner space can decrease at least in sections along the axis in the direction of the outlet. The area of ​​the inlet can be larger than the area of ​​the outlet.

[0022] The process gas may include or may be nitrogen (N2). The process gas may also be oxygen (O2), compressed air and / or a gas mixture.

[0023] The channel of the nozzle cooling element can completely surround or partially surround the inner cavity. Preferably, the channel surrounds the inner cavity by at least 180°.

[0024] The bottom of the channel may connect the first side wall to the second side wall, so that the channel has a substantially U-shaped cross section perpendicular to its longitudinal extension (in the circumferential direction). The bottom may be configured substantially perpendicular to the first side wall and / or the second side wall. "Substantially perpendicular" may mean an angle range of 90°±20°, 90°±10°, 90°±5° or 90°±2°.

[0025] At least two of the first side wall, the second side wall and the bottom may be integrally constructed.

[0026] The first side wall and / or the second side wall may have a height (along the lumen axis) of at least 1 mm, preferably at least 5 mm. The bottom may have a width (along the radial direction) of at least 1 mm, preferably at least 3 mm.

[0027] The outer diameter (perpendicular to the inner cavity axis) of the nozzle cooling element may be at least 32 mm, preferably at least 35 mm, preferably at least 39 mm.

[0028] The nozzle cooling element can be designed such that, when the nozzle cooling element is connected to the laser processing device, the channel is open to the environment of the laser processing device on a side of the channel facing the inlet of the interior for the processing laser beam.

[0029] In other words, the nozzle cooling element can be designed in such a way that, when the nozzle cooling element is connected to the laser processing device, the channel is open upwards or in the direction of the inlet of the interior space with respect to the surroundings of the laser processing device.

[0030] The first side wall of the channel can be opposite to the second side wall of the channel. In particular, the first side wall and the second side wall are configured parallel to each other. Alternatively or additionally, the opening of the channel can be opposite to the bottom of the channel. The channel can be open on one side at most. In particular, the upper side of the channel is open. The opening of the channel can be configured annularly and / or surround the inner cavity and / or be configured along a circumferential direction around the inner cavity.

[0031] The cooling fluid may be a gas. The gas may be air, in particular ambient air or compressed air or a gas mixture.

[0032] The cooling fluid can flow into the channel of the nozzle cooling element via the opening of the channel and / or the cooling fluid can flow out of the channel via the (same) opening. If there is a distance between the outlet of the cooling fluid supply and the channel, the cooling fluid flowing out of the opening of the channel can flow into the nozzle cooling element or the surroundings of the laser processing device.

[0033] The bottom of the channel may extend in the circumferential direction around the inner cavity over at least 50% of the total length of the channel in the circumferential direction. Preferably, the bottom of the channel extends in the circumferential direction around the inner cavity over at least 60%, preferably at least 80%, preferably at least 90%, preferably at least 95% of the total length of the channel in the circumferential direction. The bottom may extend in the circumferential direction around the inner cavity over the entire length of the channel in the circumferential direction.

[0034] The bottom of the channel can be interrupted in the circumferential direction around the inner cavity or completely (through the entire circumferential extension) closed. When the bottom of the channel is configured interrupted, the bottom can have one or more notches. The notches can be holes. A plurality of notches can be arranged regularly or irregularly along the longitudinal extension of the bottom (in the circumferential direction). At least a portion of the cooling fluid introduced into the channel can flow out of the channel via the notches on the bottom of the channel. This portion of the cooling fluid can flow into the nozzle cooling element or the surrounding environment of the laser processing device.

[0035] The nozzle cooling element may have a nozzle tip. The nozzle tip may be integrated into the nozzle cooling element or may be integrally formed with the nozzle cooling element. Alternatively, the nozzle cooling element may be connectable to the nozzle tip. The machining laser beam and the process gas may be emitted from the nozzle tip. The outlet of the nozzle tip may have a cross section that is smaller than the cross section of the inlet of the inner cavity of the nozzle cooling element.

[0036] The nozzle tip is understood to be a known nozzle. The nozzle cooling element is in this case an additional element which can be inserted between the laser processing device and the known nozzle.

[0037] The nozzle cooling element may include a semi-finished product or consist of a semi-finished product. In particular, the nozzle cooling element has been produced from a semi-finished product. The semi-finished product may be a preformed blank. The semi-finished product may be produced by an additive manufacturing method, such as laser beam melting or laser sintering. The nozzle cooling element may consist of copper or a copper alloy, in particular, a semi-finished product consisting of copper or a copper alloy.

[0038] The nozzle cooling element may have at least two circumferential channels. Preferably, the nozzle cooling element has at least three, preferably at least four channels. The nozzle cooling element may have one to five channels, preferably three to five channels, preferably exactly four channels. Each of the channels may be any channel disclosed herein that circumferentially surrounds the inner cavity.

[0039] The channels can be configured concentrically in the nozzle cooling element. That is, the channels further outward in the radial direction can have a larger diameter than the channels inward in the radial direction.

[0040] The channels may be spaced apart in radial direction. The spacing between two (directly adjacent) channels in radial direction may be at least 1 millimeter.

[0041] A rib may be configured between the at least two surrounding channels. The rib may completely surround the inner cavity. The rib may completely surround one of the channels.

[0042] The upper side of the rib (against the direction of gravity) can be designed to be higher than the bottom of the radially adjacent channel. Preferably, the upper side of the rib is inclined. In particular, the radially outer edge of the upper side of the rib can be arranged higher than the radially inner edge of the upper side of the rib. In this case, the angle between the upper side of the rib and the bottom can be between 10° and 60°, preferably between 10° and 45°, preferably between 10° and 30°.

[0043] The nozzle cooling element may have a plurality of ribs. In particular, one rib is configured between two channels in the radial direction. If the nozzle cooling element has four channels, for example, three ribs may be provided. Here, one rib is configured between two channels.

[0044] The height of these ribs (height in the direction of the inner cavity axis) can be equal. That is, all ribs can have equal spacing between the bottom of the radial inside of the passage and the upper side (highest point) of the rib. Alternatively, these ribs can be configured to have different heights.

[0045] Each of the ribs may be any type of rib disclosed herein.

[0046] A radial end rib can be formed in the nozzle cooling element. The radial end rib can adjoin at most one channel in the nozzle cooling element. Preferably, the radial end rib is the radially outermost rib of the nozzle cooling element. The radial end rib can terminate the nozzle cooling element radially outwards.

[0047] The radial end rib can have a flange. The flange can be formed on the radial outer part of the end rib.

[0048] The nozzle cooling element may have at least three circumferential channels. A first rib may be formed between the first circumferential channel and the second circumferential channel. A second rib may be formed between the second circumferential channel and the third circumferential channel. Each of the first rib and the second rib may have an upper side facing the inner cavity for the inlet of the processing laser beam. The upper side of the second rib may be higher (against the direction of gravity) than the upper side of the first rib.

[0049] The second channel may be radially further outward than the first channel. The third channel may be radially further outward than the second channel. The second rib may be radially further outward than the first rib.

[0050] The nozzle cooling element can have a plurality of ribs. Preferably, the nozzle cooling element has at least two, preferably at least three, preferably at least four ribs. The upper side of the radially outer ribs can be higher than the upper side of the (directly adjacent) radially inner ribs. The height of the ribs can be constant.

[0051] The ribs of the nozzle cooling element may be arranged to rise in a stepped manner as the radial distance from the inner cavity increases. As the radial distance from the inner cavity increases, the corresponding upper side of the rib may be higher.

[0052] The bottom of the channel of the nozzle cooling element may be arranged to rise in a stepped manner as the radial distance from the inner cavity increases. As the radial distance from the inner cavity increases, the corresponding bottom may become higher.

[0053] The second side wall of the channel may have at least one slit. In particular, the second side wall of the channel has a plurality of slits.

[0054] The gap can be constructed starting from the upper side of the second side wall. In particular, the gap ends above the bottom of the channel starting from the upper side. In other words, in the region with the gap in the second side wall, the height of the second side wall can be reduced.

[0055] It is also possible that the slot extends from the upper side of the second side wall to the bottom of the channel. The height of the second side wall can be equal to zero in the region with the slot.

[0056] The cooling fluid flowing into the channel can flow from the channel via the gap into the nozzle cooling element or into the surroundings of the laser processing device.

[0057] If a slot is formed in the second side wall, the nozzle cooling element may have a maximum of one channel. Alternatively or additionally, the nozzle cooling element may not have a rib radially between two channels. This is only an example, and it is possible that the nozzle cooling element has a slot in the second side wall and a plurality of channels and / or at least one rib radially between two channels.

[0058] A plurality of slots may be formed in the second side wall. For example, at least five, at least ten or at least twenty slots may be formed in the second side wall.

[0059] The gaps can be configured to be distributed in the circumferential direction. Preferably, the gaps are configured to be evenly distributed in the circumferential direction.

[0060] Each of the gaps may be any of the gaps disclosed herein.

[0061] The second side wall and / or the bottom of the channel may have at least one notch. The notch may be a hole. The channel may be connected to the nozzle cooling element or the surroundings of the laser processing device through the notch.

[0062] The center axis of the slot can be angled radially outward relative to the lumen axis. Preferably, the angle between the center axis of the slot and the lumen axis is at least 10°, preferably between 30° and 60°, preferably between 40° and 50°.

[0063] The notch can be formed both (partially) in the second side wall and (partially) in the bottom. Alternatively, the notch can be formed only in the second side wall or only in the bottom.

[0064] The slot can be at least partially closed by a closure. The closure can completely close the slot, so that the cooling fluid cannot flow from the channel through the slot into the nozzle element or the surroundings of the laser processing device. It is also possible that the closure at most partially closes the slot, so that the cooling fluid can flow from the channel through the slot into the nozzle element or the surroundings of the laser processing device. When the closure is arranged in the slot and the cooling fluid can flow from the channel through the slot into the nozzle element or the surroundings of the laser processing device, the volume flow of the cooling fluid that can flow out is smaller than when the closure is not arranged in the slot.

[0065] In particular, the closure can be inserted into and removed from the slot. The slot and the closure can be designed such that the volume flow of cooling fluid that can flow from the channel into the nozzle element or the surroundings of the laser processing device can be controlled or regulated by different positioning of the closure.

[0066] The closure part may be a control or regulating valve. The closure part may be a screw that can be screwed into the slot. Likewise, the closure part may be a pin. The pin can be inserted into the slot.

[0067] Preferably, the second side wall and / or the bottom of the channel has a plurality of notches. At least five notches or at least ten notches may be provided.

[0068] Each of the slots can be any slot disclosed herein. Each of the slots can be closed or closable by any closure portion disclosed herein.

[0069] The slots can be distributed uniformly or non-uniformly in the circumferential direction. Likewise, the closures in the slots can be arranged uniformly or non-uniformly. For example, it can be provided that different volume flows flow from the channel via different slots into the nozzle cooling element or the surroundings of the laser processing device. For this purpose, the closures can be arranged differently or non-uniformly in the slots.

[0070] A cooling channel for guiding a cooling fluid can be formed in the laser processing device body, the cooling channel having an outlet. The outlet of the cooling channel can be spaced apart from the opening of the channel in the nozzle cooling element. In particular, a space is formed between the outlet of the cooling channel and the opening of the channel, which space is connected to the surroundings of the laser processing device through flow.

[0071] The outlet of the cooling channel may not be directly connected to the opening of the channel in the nozzle cooling element. The outlet of the cooling channel may be spaced apart from the opening of the channel in the nozzle cooling element. In other words, there may be a gap between the outlet of the cooling channel and the opening of the channel in the nozzle cooling element, which gap is part of the environment of the nozzle cooling element or of the laser processing device or is connected to it through flow. The cooling fluid may flow into the channel of the nozzle cooling element via the gap and the inflowing cooling fluid may flow (at least for the most part) from the channel via the gap into the environment.

[0072] The outlet of the cooling channel may be spaced apart from the opening of the channel in the nozzle cooling element by at least 5 millimeters, preferably at least 10 millimeters.

[0073] The radial direction may be oriented perpendicularly to an axis defined by a center point of an inlet for the machining laser beam and a center point of an outlet for the machining laser beam. The outlet of the cooling channel may be spaced apart from the opening of the channel in the radial direction. In particular, the outlet of the cooling channel is spaced apart from the opening of the channel in the radial direction by at least 5 millimeters.

[0074] In other words, the outlet of the cooling channel may be spaced apart from the opening of the channel in the nozzle cooling element perpendicularly to the inner cavity axis in a radial direction, preferably by at least 5 mm, preferably by at least 10 mm.

[0075] The distance in the radial direction between the outlet of the cooling channel and the radially outer end of the nozzle cooling element can be at least 5 mm, in particular at least 7 mm or at least 10 mm.

[0076] The laser processing device body may include at least one of the following elements: a housing for receiving at least one optical element; an insulating member for electrically insulating the housing relative to the nozzle cooling element; a fixing portion for fixing the insulating member to the housing, in particular a locking nut Fastening means, in particular threads, for fastening the nozzle cooling element to the insulating part.

[0077] The at least one optical element may include or may be collimating optics, focusing optics, a beam splitter, a protective glass, a lens, a transmissive element, a reflective element, a beam shaping element and / or an optical wedge.

[0078] The insulating member may be non-conductive. The insulating member may be an electrical insulator. Preferably, the insulating member comprises or consists of ceramic.

[0079] The fixing portion for fixing the insulating member to the housing may include a part of the cooling channel. The fixing portion may (directly) contact the housing and the insulating member.

[0080] The fixing portion for fixing the nozzle cooling element on the insulating member may be a metal threaded portion. The fixing portion may (directly) contact the insulating member and the nozzle cooling element. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] The present invention will be described in detail below with reference to the accompanying drawings.

[0082] Figure 1 A laser processing system 2000 is shown;

[0083] Figure 2 The laser processing apparatus body 1000, 900, 800, 700 and the nozzle cooling element 400 are shown;

[0084] Figure 3 The enlarged part shows Figure 2 The laser processing device body 1000, 900, 800, 700 and the nozzle cooling element 400;

[0085] Figure 4 The laser processing apparatus body 1000, 900, 800, 700 and the nozzle cooling element 500 are shown;

[0086] Figure 5 The enlarged part shows Figure 4 The laser processing apparatus body 1000, 900, 800, 700 and the nozzle cooling element 500; and

[0087] Figure 6 The laser processing apparatus body 1000 , 900 , 800 , 700 and the nozzle cooling element 600 are shown. DETAILED DESCRIPTION

[0088] Figure 1 The laser processing system 2000 is shown, which has a laser processing device 100 (also referred to as a laser processing head). The laser processing system 2000 may include a control device 300 and a laser source 200.

[0089] The laser source 200 can generate a machining laser beam L (laser beam). The laser source 200 can be designed as a single-mode laser, a solid-state laser or a fiber laser.

[0090] The processing laser beam L generated by the laser source 200 can be transmitted from the laser source 200 to the laser processing device 100 via an optical fiber. The processing laser beam L can be coupled into the laser processing head 100 via a fiber coupler 140. The fiber coupler 140 can be arranged on the housing 1000 of the laser processing device 100.

[0091] The laser processing device 100 may include a collimator optics 121. The collimator optics 121 may be arranged and configured in the laser processing device 100 so that the processing laser beam L divergently entering the laser processing device 100 is collimated. The collimator optics 121 may be arranged in a housing 1000 of the laser processing device 100.

[0092] The collimating optics 121 may comprise at least one lens or two or more lenses. The spacing between the two or more lenses may be adjustable, in particular by means of an electric motor. The collimating optics 121 may define an optical axis.

[0093] Furthermore, the laser processing device 100 may include focusing optics 122 . The focusing optics 122 may be arranged and configured in the laser processing device 100 in such a way that the collimated processing laser beam L is focused. The focusing optics 122 may be arranged in a housing 1000 of the laser processing device 100 .

[0094] The focusing optics 122 may include at least one lens or two or more lenses. The spacing between the two or more lenses may be adjustable, in particular by means of a motor. An optical axis may be defined by the focusing optics 122. The focusing optics 131 may be an F-Theta objective.

[0095] The focused machining laser beam L may be emitted from the laser machining apparatus 100 and may be emitted onto the workpiece W to machine the workpiece W.

[0096] The nozzle cooling element 400, 500, 600 is arranged on the laser processing device 100. The processing laser beam L from the laser processing device 100 is emitted from the nozzle cooling element 400, 500, 600. At the same time, the process gas is emitted from the nozzle cooling element 400, 500, 600.

[0097] For example, workpieces W can be welded. In this case, two workpieces W can be welded to one another or a component can be welded to a workpiece W. Workpieces W can also be cut or soldered.

[0098] The laser processing device 100 may be a laser beam welding head, a laser beam cutting head, or a laser beam brazing head.

[0099] Furthermore, the laser processing apparatus 100 may include lenses, transmissive elements, reflective elements, beam shaping elements, beam splitters, and / or optical wedges.

[0100] The optical path of the machining laser beam L through the laser machining device 100 can be determined by the optical elements of the laser machining device 100 .

[0101] The control device 300 can control the operation of the laser processing device 100. In particular, the control device 300 can control the laser power and / or the position and / or posture of at least one optical element.

[0102] Figure 2 The laser processing apparatus body 1000 , 900 , 800 , 700 and the nozzle cooling element 400 are shown.

[0103] The laser processing device body 1000, 900, 800, 700 may include a housing 1000. At least one optical element 121, 122 may be received in the housing 1000. Preferably, at least one collimating optical device and a focusing optical device are arranged in the housing 1000. Figures 2 to 6 , the housing 1000 is only partially shown.

[0104] The laser processing device body 1000, 900, 800, 700 may include an insulating member 800. The insulating member 800 may be an electrical insulator. Preferably, the insulating member includes or consists of ceramic.

[0105] The laser processing apparatus body 1000, 900, 800, 700 may include a fixing portion 900. The fixing portion 900 may be configured to connect the insulating member 800 to the housing 1000. The fixing portion 900 may be a locking nut.

[0106] The laser processing apparatus body 1000, 900, 800, 700 may include a fixing portion 700. The fixing portion 700 may be configured to connect the nozzle cooling element 400 with the insulating member 800. The fixing portion may be a metal threaded portion.

[0107] Since the nozzle cooling element 400 is connected to the housing 1000 via the insulating member 800, the housing 1000 is electrically insulated from the nozzle cooling element 400. The nozzle cooling element 400 can be used as a distance sensor for determining the distance between the laser processing device 100 or the nozzle cooling element 400 and the workpiece W. The distance can be determined based on the measurement of capacitance.

[0108] An inner cavity 1010 can be formed in the housing 1000, through which the machining laser beam L and the process gas can be guided. Another inner cavity 810 can be formed in the insulating part 800. The inner cavity 810 in the insulating part 800 is preferably configured so that the inlet of the inner cavity 810 is matched to the outlet of the inner cavity 1010 in the housing 1000. Another inner cavity 420 is formed in the nozzle cooling element 400. The inner cavity 420 of the nozzle cooling element 400 has an inlet 421 and an outlet 422. The machining laser beam L and the process gas can be injected into the inner cavity 420 via the inlet 421, and the machining laser beam L and the process gas can be injected from the inner cavity 420 via the outlet 422 from the nozzle cooling element 400.

[0109] The inlet 421 of the machining laser beam L into the inner cavity 420 of the nozzle cooling element 400 and the outlet 422 of the machining laser beam L from the inner cavity 420 of the nozzle cooling element 400 can define an axis (also referred to as the inner cavity axis), in particular as described at the beginning. The radial direction can be oriented perpendicular to the axis. The outlet 422 of the inner cavity 400 can be understood as "down". The inlet 421 of the inner cavity 400 can be understood as "up". "Up" and "down" can be defined by the direction of gravity.

[0110] A cooling channel 1020 may be formed in the housing 1000. A cooling fluid, such as a cooling gas, may be guided through the cooling channel 1020. A cooling channel 920 may also be formed in the fixing part 900, through which a cooling fluid may be guided. The cooling channels 1020, 920 of the housing 1000 and the fixing part 900 may form a common cooling channel. Likewise, the cooling channel may be formed only in one element of the laser processing device 100, such as in the housing 1000. The cooling fluid may flow out from an outlet 921 of the cooling channel 920 of the fixing part 900. Preferably, the outlet 921 is open relative to the surroundings, i.e., the cooling fluid may flow out from the outlet 921 into the surroundings of the laser processing device 100. In particular, the cooling fluid may flow in the direction of the nozzle cooling element 400.

[0111] The nozzle cooling element 400 has at least one channel 410, 411, 412, 413. The channel 410, 411, 412, 413 surrounds the inner cavity 420 of the nozzle cooling element 400. Preferably, the channel 410, 411, 412, 413 completely surrounds the inner cavity 420 of the nozzle cooling element 400.

[0112] exist Figure 3As can be seen in FIG. 4 (where an enlarged view of a section of the channel 410 is shown), the channel 410 includes a first side wall 410a, a second side wall 410c and a bottom 410b. The bottom 410b connects the first side wall 410a to the second side wall 410c. In particular, the first side wall 410a, the bottom 410b and the second side wall 410c are integrally formed or materially connected to each other.

[0113] The bottom 410b of the channel 410 is arranged downward, that is, in the direction of gravity or in the direction of the workpiece W to be processed. Opposite to the bottom 410b, an opening 410d of the channel 400 is formed. The cooling fluid flowing out of the outlet 921 can flow into the channel 410 through the opening 410d. Here, the cooling fluid can pass through the gap 930 between the laser processing device 100 and the nozzle cooling element 400.

[0114] The opening 410d may be the only opening of the channel 410, so that the cooling fluid may flow out of the channel 410 via the opening 410d. The opening 410d may surround the inner cavity 420, in particular completely surround it.

[0115] The nozzle cooling element is effectively cooled when the cooling fluid flows from the outlet 921 via the gap 930 into the channel 410 and flows out from the channel 410 via the gap 930 in the direction of the surroundings of the laser processing device 100 or the nozzle element 400. At the same time, the outflowing (heated) cooling fluid has no influence or only a slight negative influence on the process gas flow out of the outlet 422 of the inner cavity 420 of the nozzle cooling element.

[0116] The nozzle cooling element 400 may have a plurality of channels 410, 411, 412, 413 (see also Figure 2 ). Each of channels 411 , 412 , 413 may be constructed similarly or identically to channel 410 .

[0117] The channels 410, 411, 412, 413 may be arranged concentrically around the inner cavity 420. The channels 410, 411, 412, 413 may be evenly or unevenly spaced in the radial direction. A cooling fluid may flow into and out of each of the channels 410, 411, 412, 413. This further improves cooling efficiency through improved heat transfer.

[0118] A rib 430, 431, 433 may be formed between the channels 410, 411, 412, 413. Here, one rib 430, 431, 433 may be formed between each two channels of the channels 410, 411, 412, 413. Figure 2 In the example of FIG. 4 , four channels 410 , 411 , 412 , 413 400 and three ribs 430 , 431 , 432 are formed in the nozzle cooling element 400 .

[0119] An end rib 433 may be configured at the radial end of the radially outer channel 413. The end rib 433 may include a surrounding flange 433a. The flange 433a may completely surround the inner cavity 420. The flange 433a may extend radially outward.

[0120] Each of the ribs 430 , 431 , 432 , 433 may have an upper side 430 a , 431 a , 432 a , 433 a which is oriented counter to the direction of gravity or in the direction of the inlet 421 of the nozzle cooling element 400 or away from the workpiece W.

[0121] Each of the upper side surfaces 430a, 431a, 432a, 433a may be inclined. The angle between the upper side surface 430a, 431a, 432a, 433a of each rib 430, 431, 432, 433 and the corresponding bottom may be between 10° and 60°. The corresponding bottom may be the bottom adjacent radially inside or outside. The angle may also exist between each upper side surface 430a, 431a, 432a, 433a and the radial direction.

[0122] The upper side surface 433a of the last rib 433 may be non-inclined. In particular, the upper side surface 433a of the last rib 433 is parallel to the bottom of the adjacent channel or parallel to the radial direction.

[0123] The heights of the ribs 430, 431, 432, 433 may be equal. That is, all the ribs 430, 431, 432, 433 may have equal heights. Likewise, the ribs 430, 431, 432, 433 may have different heights. Here, the radially innermost rib may have the smallest height, while the radially outermost rib may have the largest height. The height of the intermediate ribs may increase from the radial inner side to the radial outer side.

[0124] The upper side 430a of the radially innermost rib 430 may be below (in the direction of gravity) the upper side 431a of the radially outermost rib 431. Generally, the upper side of the radially innermost rib may be higher than the upper side of the radially outermost rib.

[0125] The upper side of the ribs can be arranged in a stepped manner (as the position moves radially toward the outside).

[0126] The nozzle cooling element 400 may include a nozzle tip 450. The nozzle cooling element 400 and the nozzle tip 450 may be formed integrally or may be connected to one another in a materially bonded manner.

[0127] There may be a distance in the radial direction between the outlet 921 of the cooling channel 1020 , 920 and the channel 410 , in particular the opening 410 d of the channel 410 . The outlet 921 may be formed in the fixing part 900 .

[0128] The outlet 921 of the cooling channel 1020, 920 may be radially adjacent to the radially outer end of the nozzle cooling element 400 (see Figure 2 and Figure 3 ). The distance s1 in the radial direction between the outlet 921 of the cooling channel 1020, 920 and the radially outer end of the nozzle cooling element 400 can be at least 5 mm, in particular at least 7 mm or at least 10 mm. This can reduce or avoid adverse effects on the process gas flow.

[0129] Figure 4 and Figure 5 FIG. 5 shows an embodiment of a nozzle cooling element 500. The nozzle cooling element 500 is shown in FIG. Figure 2 and Figure 3 The description of the laser processing device body 1000, 900, 800, 700 also applies to the embodiment described in the embodiment of the present invention. Figure 4 and Figure 5 The embodiments of the nozzle cooling element 500 are described above and are not repeated here.

[0130] The inner chamber 520 of the nozzle cooling element 500 has an inlet 521 and an outlet 522 . The machining laser beam L and the process gas can be injected into the inner chamber 520 via the inlet 521 , and can be injected out of the inner chamber 520 via the outlet 522 from the nozzle cooling element 500 .

[0131] The inlet 521 of the machining laser beam L into the inner cavity 520 of the nozzle cooling element 500 and the outlet 522 of the machining laser beam L from the inner cavity 520 of the nozzle cooling element 500 can again define an axis (also referred to as the inner cavity axis). The radial direction can be oriented perpendicular to the axis. The outlet 522 of the inner cavity 500 can be understood as "down". The inlet 521 of the inner cavity 500 can be understood as "up". "Up" and "down" can be defined by the direction of gravity.

[0132] The nozzle cooling element 500 has at least one channel 510. The channel 510 surrounds the inner cavity 520 of the nozzle cooling element 500. Preferably, the channel 510 completely surrounds the inner cavity 520 of the nozzle cooling element 500. The nozzle cooling element 500 may have exactly one channel 510.

[0133] As in Figure 5As shown in FIG. 5 (where an enlarged view of a portion of the channel 510 is shown), the channel 510 includes a first side wall 510a, a second side wall 510c and a bottom 510b. The bottom 510b connects the first side wall 510a to the second side wall 510c. In particular, the first side wall 510a, the bottom 510b and the second side wall 510c are integrally constructed or materially connected to each other.

[0134] The second sidewall 510c may be configured substantially perpendicular to the bottom 510b. "Substantially perpendicular" may refer to an angle range of 90°±20°, 90°±10°, 90°±5°, or 90°±2°.

[0135] An angle different from 90° may be formed between the first side wall 510a and the bottom 510b. The angle between the first side wall 510a and the bottom 510b may be between 90° and 150°, preferably between 95° and 150°, preferably between 95° and 135°.

[0136] The first side wall 510 a and the second side wall 510 c may not be parallel to each other.

[0137] The second side wall 510c may have a height of at least 10 mm, preferably at least 15 mm, preferably at least 20 mm.

[0138] The bottom 510b of the channel 510 is arranged downward, that is, in the direction of gravity or in the direction of the workpiece W to be processed. An opening 510d of the channel 500 is formed opposite to the bottom 510b. The cooling fluid can flow into the channel 510 through the opening 510d. Here, the cooling fluid can pass through the gap between the laser processing device 100 and the nozzle cooling element 500.

[0139] The opening 510 d may surround the inner cavity 520 , in particular completely surround it.

[0140] An end rib 533 may be formed at the radial end of the channel 510. The end rib 533 may have an upper side 533a. The upper side 533a is oriented in this case counter to the direction of gravity or in the direction of the inlet 521 of the nozzle cooling element 500 or away from the workpiece W.

[0141] The upper side 533a may be inclined. The angle between the upper side 533a of the rib 533 and the corresponding bottom 510b may be between 10° and 60°. In particular, the angle is between 10° and 45°, preferably between 10° and 40°. The angle may also exist between the upper side 533a and the radial direction.

[0142] The second side wall 510c of the channel 510 may have at least one slit 560. The slit 560 may extend from the upper side 533a of the second side wall or the end rib 533a in the direction of the bottom 510b. Preferably, the slit 560 does not extend to the bottom 510b. The slit 560 may be spaced apart from the bottom. In the region of the slit 560, the height of the second side wall 510c may be reduced. In particular, the height of the second side wall 510c in the region of the slit 560 is greater than zero.

[0143] The cooling fluid can flow from the channel 510 via the gap 560 in the direction of the nozzle cooling element 500 or the surroundings of the laser processing device 100 .

[0144] The nozzle cooling element 500, in particular the second side wall 510c of the channel 500, may include a plurality of slits 560. The slits 560 may be evenly distributed (in the circumferential direction) or unevenly distributed along the second side wall 510c.

[0145] The nozzle cooling element 500 can be connected or connected to the nozzle tip 550. The connection can be releasable. Preferably, the nozzle tip 550 is screwed to the nozzle cooling element 500.

[0146] Figure 6 FIG. 6 shows an embodiment of a nozzle cooling element 600. The nozzle cooling element 600 is shown in FIG. Figure 2 and Figure 3 The description of the laser processing device body 1000, 900, 800, 700 also applies to the embodiment described in the embodiment of the present invention. Figure 6 The embodiment of the nozzle cooling element 600 is described and is not repeated. Except for the differences described below, the nozzle cooling element 600 corresponds to the nozzle cooling element 500. The differences described below can also be Figure 2 and Figure 3 The nozzle cooling element 400 is implemented in the nozzle cooling element 400.

[0147] At least one notch 670 may be formed in the second side wall 610c and / or in the bottom 610b of the channel 610. Preferably, the notch is formed partly in the second side wall 610c of the channel and partly in the bottom 610b.

[0148] The cooling fluid can flow from the channel 610 via the slot 670 into the nozzle cooling element 600 or the surroundings of the laser processing device 100 .

[0149] The slot 670 can be closed, partially open or completely open. In order to (completely) close the slot 670, a closure 671 can be arranged or arranged in the slot 670. The closure 671 can be a screw or a control or regulating valve. The closure 671 can be partially opened or partially removed so that the slot is partially open. If the closure 670 is removed from the slot 671, the slot 670 can be completely opened.

[0150] The volume flow of the cooling fluid that can flow out through the slot 670 can be adjustable via the slot 670 and the closure 671. The volume flow that can flow out can be controlled or regulated by the control device 300. To this end, the control device 300 can cause a change in the position or posture of the closure 671 in the slot 670.

[0151] The notch 670 may be disposed below the gap 560 .

[0152] The nozzle cooling element 600 may include a plurality of slots 670. In each of the slots 670, a closed portion 671 may be arranged. The slots 670 may be configured to be evenly distributed (in the circumferential direction) or unevenly distributed along the channel 610.

[0153] Compared to conventional nozzles, the nozzle cooling element according to the invention provides for more effective cooling due to the increase in the outer diameter and the increase in the cooling surface by means of cooling ribs on the rear side. By increasing the cooling surface on the upper side of the nozzle cooling element (for example by means of ribs), the supplied cooling fluid is guided longer over the nozzle cooling element and distributed simultaneously over a larger surface to be cooled.

Claims

1. A nozzle cooling element (400, 500, 600) for a laser processing device (100) for processing a workpiece (W) by means of a processing laser beam (L), wherein: The nozzle cooling element (400, 500, 600) has an inner cavity (420, 520) for the passage of a machining laser beam (L) and a process gas, wherein the inner cavity (420, 520) has an inlet (421, 521) for the machining laser beam (L) and an outlet (422, 522) for the machining laser beam (L), The nozzle cooling element (400, 500, 600) has at least one channel (410, 411, 412, 413, 510, 610) surrounding the inner cavity (420, 520), and a cooling fluid can flow into the channel to cool the nozzle cooling element (400, 500, 600), and The channel (410, 411, 412, 413, 510, 610) has a first side wall (410a, 510a), a second side wall (410c, 510c) and a bottom (410b, 510b) connecting the first side wall (410a, 510a) and the second side wall (410c, 510c).

2. The nozzle cooling element (400, 500, 600) according to claim 1, wherein: The nozzle cooling element (400, 500) is configured such that, when the nozzle cooling element (400, 500, 600) is connected to a laser processing device (100), the channel (410, 411, 412, 413, 510, 610) is open to the surroundings of the laser processing device (100) on a side of the channel (410, 411, 412, 413, 510, 610) facing an inlet (421, 521) of an inner cavity (420, 520) for a processing laser beam (L).

3. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The first side wall (410a, 510a) is opposite to the second side wall (410c, 510c), and / or the opening (410d, 510d) of the channel (410, 411, 412, 413, 510, 610) is opposite to the bottom (410b, 510b).

4. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The bottom (410b, 510b) extends along at least 50% of the total length of the channel (410, 411, 412, 413, 510, 610) along the circumferential direction around the inner cavity (420, 520), and / or, wherein the bottom (410b, 510b) is interrupted or completely closed along the circumferential direction around the inner cavity (420, 520).

5. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The nozzle cooling element (400) has a nozzle tip (450) or the nozzle cooling element (500, 600) is connectable to the nozzle tip (550, 650).

6. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The nozzle cooling element (400, 500, 600) is manufactured from a semi-finished product.

7. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The nozzle cooling element (400) has at least two circumferential channels (410, 411, 412, 413), preferably at least three circumferential channels.

8. The nozzle cooling element (400, 500, 600) according to claim 7, wherein: A rib (430, 431, 432, 433) is constructed between the at least two surrounding channels (410, 411, 412, 413), in particular, wherein the rib (430, 431, 432, 433) completely surrounds the inner cavity (420) and / or wherein the rib (430, 431, 432, 433) completely surrounds one of the channels (410, 411, 412, 413).

9. The nozzle cooling element (400, 500, 600) according to claim 7 or 8, wherein: The nozzle cooling element (400, 500, 600) has at least three circumferential channels (410, 411, 412, 413), a first rib (430) being configured between a first circumferential channel (410) and a second circumferential channel (411), and a second rib (431) being configured between the second circumferential channel (411) and a third circumferential channel (412), wherein each of the first and second ribs (430, 431) has an upper side (430a, 431a) facing an inlet (421) of an inner cavity (420) for a machining laser beam (L), and the upper side (431a) of the second rib (431) is higher than the upper side (430a) of the first rib (430).

10. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The second side wall (510c, 610c) of the channel (510, 610) has at least one slit (560), and in particular, the second side wall (510c, 610c) of the channel (510, 610) has a plurality of slits (560).

11. The nozzle cooling element (400, 500, 600) according to any one of the preceding claims, wherein: The second side wall (610c) and / or the bottom (610b) of the channel (610) has at least one notch (670), and in particular, the second side wall (610c) and / or the bottom (610b) of the channel (610) has a plurality of notches (670).

12. A laser processing device (100) for processing a workpiece (W) by means of a laser beam (L), the laser processing device (100) comprising: Laser processing equipment body (1000, 900, 800, 700); and A nozzle cooling element (400, 500, 600) according to any one of the preceding claims connected to a laser processing device body (1000, 900, 800, 700).

13. The laser processing device (100) according to claim 12, wherein: A cooling channel (1020, 920) for guiding a cooling fluid is formed in a laser processing device body (1000, 900, 800, 700), the cooling channel having an outlet (921), wherein the outlet (921) of the cooling channel (1020, 920) is spaced apart from an opening (410d, 510d) of the channel (410, 411, 412, 413, 510), in particular, wherein a space (930) is formed between the outlet (921) of the cooling channel (1020, 920) and the opening (410d, 510d) of the channel (410, 411, 412, 413, 510), and the space is connected to the surrounding environment of the laser processing device (100) through flow.

14. The laser processing device (100) according to claim 13, wherein: The radial direction is oriented perpendicularly to an axis defined by a center point of an inlet (421, 521) for a machining laser beam (L) and a center point of an outlet (422, 522) for the machining laser beam (L), wherein the outlet (921) of the cooling channel (1020, 920) is spaced apart from an opening (410d, 510d) of the channel (410, 411, 412, 413, 510) in the radial direction, in particular by at least 5 millimeters.

15. The laser processing device (100) according to any one of claims 12 to 14, wherein: The laser processing device body (1000, 900, 800, 700) includes at least one of the following elements: A housing (1000) for receiving at least one optical element (121, 122); an insulating member (800) for electrically insulating the housing (1000) relative to a nozzle cooling element (400, 500); a fixing portion (900), in particular a locking nut, for fixing the insulating member (800) to the housing (1000); and a fixing portion (700), in particular a threaded portion, for fixing the nozzle cooling element (400, 500) to the insulating member (800).

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