Nozzle for laser processing device and laser processing device including the same

Abstract

A nozzle for a laser processing device for processing a workpiece by means of a laser beam, wherein the nozzle comprises: a base body having an inner volume for guiding laser light and process gas and a nozzle opening, wherein the nozzle opening has an outlet opening for outputting a core flow of the laser beam and process gas; a movable sleeve having a flange area and an annular gap area, wherein the flange area can be moved along a guide area of ​​the base body, wherein the annular gap area is spaced apart from the base body and forms an annular gap with the base body for outputting an annular flow of the process gas, wherein the base body has at least one connecting channel, wherein the at least one connecting channel connects the inner volume of the base body to an area between the base body and the sleeve, so as to guide a part of the process gas into the annular gap. In addition, a laser processing device having the nozzle is provided.

Description

Technical Field

[0001] The present disclosure relates to a nozzle for a laser processing device and a laser processing device, wherein the laser processing device comprises the nozzle. The present disclosure particularly relates to a cutting nozzle for a laser processing device and a laser processing device, wherein the laser processing device comprises the cutting nozzle. Background Art

[0002] In a laser processing system for processing workpieces, in particular metal workpieces or metal materials, a laser beam output from a laser source or the end of a laser fiber is focused or bunched onto the workpiece to be processed by means of a beam guide and focusing optical device, and the laser processing system locally heats the workpiece to a melting temperature. The processing may, for example, include laser cutting, laser brazing or laser welding. The laser processing system may include a laser processing device, such as a laser processing head (referred to as "processing head"), such as a laser cutting head or a laser welding head. During processing, a laser beam is output from the laser processing device. For this purpose, a nozzle may be arranged on the processing head. The nozzle may, for example, be a cutting nozzle. When cutting a metal material or workpiece by means of a laser, a gas flow or gas flow of a process or cutting gas, which is coaxially guided, is usually output from the nozzle together with the laser beam. The laser beam and the process gas may be directed to the process area on the workpiece to be processed through the nozzle.

[0003] During the cutting process, the cutting gas performs different tasks. On the one hand, it helps to squeeze the molten material out of the cut seam by transmitting pressure and shear forces to the cutting front and the cutting surface. This function of the cutting gas plays a dominant role when cutting stainless steel, so inert media, usually nitrogen (N2), are used in this application. When cutting structural steel, reactive gases, usually oxygen (02), are used. In this application, the cutting gas supports the separation process in the form of a conversion of iron into iron oxide. In this way, in addition to the laser beam, the reaction heat is also input into the process. In addition, the function of melt extrusion is also maintained when cutting structural steel. As a third task, the cutting gas prevents the final optical element in the processing head from being contaminated by reducing process emissions through the transmission of impulses.

[0004] In order to ensure reliable expulsion of the melt, it must be ensured that a sufficient portion of the volume flow of the gas output from the cutting nozzle is also input into the cutting gap. Since, however, a certain distance between the cutting nozzle and the workpiece must be observed when cutting with a conventional nozzle laser (typically <1 mm), a certain portion of the gas always flows out onto the workpiece in a radial, horizontal or lateral direction. As a result, the gas consumption significantly increases over the volume flow actually required for the function of melt extrusion. When cutting with oxygen, processing is typically performed with an input pressure of 3 bar or less (absolute pressure measured at the inlet of the processing head). When cutting with nitrogen, processing is typically performed with a high input pressure of 2 bar to 30 bar (absolute pressure measured at the inlet of the processing head) and a correspondingly high volume flow. Therefore, the problem is particularly important when cutting with nitrogen.

[0005] In order to solve the described problem, the nozzle or parts of the nozzle, in particular the sleeve, can be placed directly on the workpiece in order to thereby suppress the radial outflow of gas and to seal the cutting gap from the surroundings.

[0006] EP 1 669 159 proposes a processing nozzle for a laser processing machine, the processing nozzle comprising a nozzle sleeve arranged on a nozzle body, wherein the nozzle sleeve protrudes from the nozzle body. A positioning portion is arranged in the lower region of the nozzle body adjacent to the nozzle body outlet opening, the positioning portion serving as a stop surface in the direction of the workpiece to be processed, thereby limiting the vertical movement of the nozzle sleeve relative to the nozzle body outlet opening.

[0007] Process emissions, such as splashes of liquid melt, dirt and metallic fumes, are generated during laser cutting. Despite the outflowing cutting gas, these emissions can also be discharged from the process area in the direction of the cutting nozzle. Since the sleeve is placed continuously on the workpiece surface during processing, the emissions easily enter the free space between the sleeve and the inner nozzle and are deposited on the surface there. In this way, the mobility of the sleeve is increasingly restricted until the sleeve can no longer fulfill its function. Typically, the entire nozzle must be replaced in this case. The more important the problem is, the narrower the gap between the inner nozzle and the sleeve is implemented. Summary of the invention

[0008] The object of the present invention is to provide a nozzle, in particular a cutting nozzle, which enables the formation of a double flow consisting of an annular flow and a core flow of the process gas. Another object of the present invention is to provide a nozzle, in particular a cutting nozzle, which has increased maintenance friendliness.

[0009] In particular, the object of the present invention is to provide a nozzle, in particular a cutting nozzle, which is less susceptible to process emissions. A further object of the present invention is to provide a nozzle, in particular a cutting nozzle, which allows replacement of individual worn parts.

[0010] The object of the present invention is also to provide a laser processing device having such a nozzle.

[0011] This object is achieved by the present invention.

[0012] The invention is based on the following basic idea: a connecting channel is provided in a base body of a nozzle, in particular a cutting nozzle, the base body having an inner volume for guiding laser light and process gas, the connecting channel connecting the inner volume to an area between the base body and a sleeve, the sleeve being arranged movably along the base body and surrounding the base body. A portion of the process gas is guided from the inner volume to an area between the base body and the sleeve that opens into an annular gap via the connecting channel, so that in addition to the inner or central core flow being discharged from the nozzle end or nozzle opening of the base body, an annular flow of the process gas surrounding the core flow is also discharged.

[0013] The aforementioned nozzle thus realizes a double flow consisting of an annular flow and a core flow. Therefore, the nozzle according to the present invention can be called a double nozzle.

[0014] According to one aspect of the present disclosure, a nozzle for a laser processing device, in particular a cutting nozzle, is provided, the laser processing device being used to process a workpiece by means of a laser beam, wherein the nozzle comprises a substrate having an internal volume for guiding a laser beam and a process gas, in particular a cutting gas, and a nozzle opening, the nozzle opening having an output opening for outputting a core flow of the laser beam and the process gas. The nozzle opening is the nozzle end with the output opening. The nozzle also comprises a movable sleeve, the sleeve having a flange area and an annular gap area, the flange area being movable or displaceable along a guide area of ​​the substrate, the annular gap area being spaced apart from the substrate and forming an annular gap with the substrate for outputting an annular flow of the process gas. The substrate also comprises at least one connecting channel, the at least one connecting channel connecting the internal volume of the substrate with the area between the substrate and the sleeve so as to guide a portion of the process gas into the annular gap.

[0015] According to a further aspect, a laser processing device for processing a workpiece by means of a laser beam is specified, wherein the laser processing device comprises a processing head and a nozzle according to one of the embodiments described herein, which is arranged on the processing head.

[0016] In the following, the axial direction or longitudinal direction refers to the direction parallel to the longitudinal axis of the substrate, which extends parallel and / or coaxially with the propagation direction or optical axis of the laser beam. The longitudinal axis of the substrate may also correspond to the central axis of the internal volume. The axial direction may be the axis of symmetry of the substrate, in particular the axis of rotational symmetry and / or may extend in the direction of the workpiece to be processed by the laser processing device. The radial direction is defined as a direction perpendicular to the axial direction. In other words, the longitudinal axis of the substrate may be regarded as the center of a rotationally symmetrical coordinate system. "Radially outward" may be referred to as a radial direction pointing away from the longitudinal axis. "Radially inward" may be referred to as a radial direction pointing toward the longitudinal axis. Accordingly, the inner radius of a component or element may be regarded as a radius having a radial direction and a face or side facing the longitudinal axis of the substrate, and the outer radius of a component or element may be regarded as a radius having a radial direction and a face or side facing away from the longitudinal axis of the substrate. The longitudinal axis of the sleeve may extend parallel and / or coaxially with the longitudinal axis of the substrate and be defined accordingly.

[0017] That is, the sleeve is movable relative to the base body. The sleeve can be movable along the guide region between a first end position and a second end position in the axial direction of the base body. Here, at least one connecting channel preferably opens at least partially into the region between the base body and the sleeve, in particular the storage volume, in each position of the sleeve.

[0018] The guide region may have an outer surface which points radially outwards and / or towards the sleeve. The outer surface may have a cylindrical shape. The cross section of the outer surface of the guide region perpendicular to the axial direction of the base body may remain constant and / or unchanged along the axial direction of the base body.

[0019] At least one connecting channel can be arranged between the guide area and the nozzle opening in the axial direction. At least one connecting channel can be arranged outside the guide area in particular. The distance between the guide area for guiding the movable sleeve and the nozzle opening or the process area is thereby increased, in which process emissions are generated. In other words, the guide area is arranged on the substrate on the side of the connecting channel away from the nozzle opening in the axial direction of the substrate. Thus, contamination or mixing of the nozzle, especially in the area between the substrate and the sleeve, caused by process emissions can be reduced or prevented, thereby maintaining the mobility of the sleeve relative to the substrate. At least one connecting channel can extend radially outward from the inner volume to the area between the substrate and the sleeve. At least one connecting channel can, for example, pass through the wall of the substrate surrounding the inner volume or extend through the wall. At least one connecting channel can be configured as a hole or through hole in the substrate. In the case of multiple connecting channels, the connecting channels can be arranged regularly or equally distributed in the circumferential direction of the substrate or the inner volume. At least one connecting channel can extend radially outward through the substrate vertically or at a certain angle relative to the longitudinal axis of the substrate.

[0020] The sleeve can be configured to be tiltable with respect to the base body. The sleeve can in particular be tiltable about at least one axis or direction perpendicular to the axial direction of the base body. Preferably, the sleeve can be tilted on the base body with the flange area. In other words, the sleeve can be configured so that it is guided along the guide area of ​​the base body only at the flange area of ​​the sleeve. The tilting is achieved in this way. If the described nozzle is configured as a contact nozzle, for example, the sleeve can be offset for unevenness on the workpiece and keep the process area, in particular the cutting gap, sealed relative to the surrounding environment even if the workpiece surface is uneven.

[0021] The sleeve can surround a part of the base body in the circumferential direction. The sleeve can limit the nozzle radially outward or toward the surrounding environment. In other words, the sleeve can be called an outer sleeve. The sleeve can be arranged on the nozzle in an outwardly exposed manner. In other words, the sleeve can be arranged outside the base body. In other words, the sleeve can constitute the outside of the nozzle. This can improve the maintenance friendliness because the sleeve can be easily touched and can therefore be easily repaired or replaced.

[0022] The area between the base body and the sleeve can define or determine the flow area of ​​the process gas. The area or the zone can be delimited towards the surroundings only by the sleeve. In particular, the volume flow of the annular flow of the process gas towards the surroundings of the nozzle can be limited only by the sleeve. Thus, the volume flow of the annular flow can only be formed between the base body, which can also be called "inner nozzle", and the sleeve.

[0023] The sleeve may further comprise a storage volume region arranged between the flange region and the annular gap region. The storage volume region of the sleeve may define, together with the substrate, a storage volume connected to the annular gap. The inner radius of the sleeve in the storage volume region may be greater than the inner radius of the sleeve in the annular gap region and / or the inner radius of the sleeve in the flange region. In other words, the inner radius of the storage volume region may be greater than the inner radius of the annular gap region and / or the inner radius of the flange region. The inner radius of the flange region may be greater than the inner radius of the annular gap region of the sleeve.

[0024] The transition from the storage volume area to the annular gap area can be realized abruptly or in steps. That is, the inner radius of the sleeve can change abruptly between the storage volume area and the annular gap area. Preferably, the transition between the storage volume area and the annular gap area has a surface that extends in a plane perpendicular to the longitudinal axis of the sleeve.

[0025] The sleeve may have an inner surface which is spaced apart from the base body and is configured so that the force caused by the process gas pressure in the region between the sleeve and the base body acts on the sleeve in the direction of the nozzle opening. The inner surface may, for example, have a first surface portion on the first side of at least one connecting channel in the axial direction of the sleeve and a second surface portion on the second side of at least one connecting channel opposite to the first side in the axial direction of the sleeve. That is, the first surface portion and the second surface portion of the inner surface may be arranged one after another along the longitudinal axis of the sleeve. The first surface portion may be arranged on the side of at least one connecting channel facing the annular gap or the nozzle opening, i.e., the side of at least one connecting channel facing away from the guide area. The second surface portion may be arranged on the side of at least one connecting channel facing away from the annular gap or the nozzle opening, i.e., the side of at least one connecting channel facing the guide area. The component of the first surface portion in a plane perpendicular to the axial direction may be greater than the component of the second surface portion in a plane perpendicular to the axial direction. Thus, a preferred direction of the sleeve movement in the direction of the nozzle opening generated by the process gas can be achieved.

[0026] The storage volume area of ​​the sleeve may include a first surface portion and a second surface portion. The second surface portion may transition abruptly or in a stepped manner into the inner surface of the annular gap area. The inner surface of the annular gap area may be arranged cylindrically around the longitudinal axis of the sleeve and / or extend in the direction of the longitudinal axis of the sleeve. The first surface portion and the second surface portion may at least partially define the boundaries of the storage volume. The first surface portion may be referred to as a "lower portion", and / or the second surface portion may also be referred to as an "upper portion". In other words, the first surface portion is arranged below the storage volume, and the second surface portion is arranged above the storage volume.

[0027] The flange area can extend radially inward and / or toward the longitudinal axis of the sleeve and / or toward the guide area of ​​the substrate. The flange area can have a cylindrical annular flange, flange or cylindrical annular projection. If the sleeve has a storage volume area, the flange area can extend radially inward and / or toward the longitudinal axis of the sleeve from the storage volume area. The flange area can surround a part of the guide area. The inner radius of the flange area can be greater than the outer radius of the guide area of ​​the substrate. The flange area can be spaced apart from the guide area. The flange area can form a gap seal with the guide area. In other words, a gap can be formed between the guide area and the flange area. Thus, when the sleeve moves relative to the substrate, the friction between the sleeve and the substrate is reduced or avoided. The gap seal also realizes a better tiltability of the sleeve with respect to the substrate. The flange area and / or the guide area can be constructed basically cylindrically annularly. The gap can be formed cylindrically annularly. Alternatively, the gap matching between the flange area and the guide area can also be realized, wherein the flange area is in sliding contact with the guide area.

[0028] The radially inwardly pointing end of the collar region or the surface facing the guide region can be rounded and / or convex, in particular semicircularly rounded, in order to simplify or enable tilting of the sleeve relative to the basic body.

[0029] The outer radius of the base body in the region of at least one connecting channel can be smaller than the outer radius of the guide region of the base body. The base body can have at least one radially outwardly protruding projection, which is configured on the end of the guide region facing the nozzle opening and which limits the movement of the sleeve in the axial direction of the base body. The outer radius of the projection can be larger than the inner radius of the flange region of the sleeve. The sleeve is arranged on the base body in such a way that the flange region of the sleeve together with the projection of the base body limits the movement of the sleeve in the axial direction of the base body. The projection can thus prevent the sleeve from slipping off in the direction of the workpiece. The projection can be configured as a flange, in particular a cylindrical annular flange, a flange or a projection.

[0030] The base body may have a fixing element, which includes a guide area and / or a projection. The fixing element can be releasably connected to a wall of the base body surrounding the inner volume of the base body. The releasable connection can be realized as a thread, a latch, by means of a bolt or the like.

[0031] The sleeve can include a first part and a second part. In other words, the sleeve can be implemented in two parts. The two parts can be releasably connected to each other. The first part can include a flange area, and the second part can include an annular gap area. By dividing the sleeve into two parts, the parts that are damaged by wear or worn can be easily accessible and easily and simply replaced when necessary. In this case, all other parts of the nozzle or sleeve can continue to be used. The maintenance friendliness of the nozzle is further improved thereby. The releasable connection of the two parts can be implemented as a thread, a latch, a bolt or the like.

[0032] The thread connecting the two parts of the sleeve to each other can have a larger radius than the thread connecting the fixing element to the wall of the base body. In one embodiment, the first part of the sleeve can be movably arranged on the base body by the fixing element. The second part of the sleeve can be designed so that the second part of the sleeve can be released from the first part in the state in which the first part is arranged on the base body by the fixing element.

[0033] The base body, the inner volume, the sleeve, the annular gap region, the storage volume region, the flange region, the flange, the guide region, the projection, the wall of the base body and / or the fastening element can be designed essentially rotationally symmetrically and / or essentially annularly, in particular cylindrically annularly.

[0034] The base body can have a cylindrical outer shape in the region between the guide region and the nozzle opening. The inner surface of the sleeve can be cylindrically shaped in the annular gap region. The annular gap can be formed in the shape of a cylindrical ring between the base body and the annular gap region of the sleeve.

[0035] At least one region of the inner volume may have a convergent, divergent, conical or cylindrical shape or a combination of said shapes.Preferably, the inner volume in the region of the nozzle opening has a conical shape which tapers towards the nozzle opening.

[0036] At least the flange area and / or the first part of the sleeve can be made of elastic material and / or can be deformed. The flange area can be configured to be sleeved on the projection of the substrate. In this case, no separate fixing element is needed for the contact nozzle or the repair nozzle.

[0037] The base body and / or the fixing element may include or consist of copper. Alternatively, the base body may include or consist of copper and the fixing element may include or consist of stainless steel. This may help prevent cold welding of the base body and the fixing element. In addition, it may be ensured that the elements can be replaced multiple times.

[0038] The sleeve can consist of an electrically insulating material, in particular ceramic, polyetheretherketone and / or plastic, or can include the same.

[0039] At least one connecting channel can be designed as an elongated hole, in particular an elongated hole oriented in the axial direction of the base body. The use of the elongated hole increases the volume flow of the process gas through the nozzle at a constant pre-pressure and a constant diameter of the connecting channel, since the flow resistance of the nozzle is reduced. In addition, the proportion of the volume flow of the annular flow of the process gas to the total volume flow is increased.

[0040] At least in one position, the movable sleeve can extend from the nozzle opening or protrude beyond the nozzle opening in the axial direction of the base body. The sleeve protruding beyond the base body can seal the process area of ​​the laser machining process, in particular the cutting gap, from the surrounding environment. The base body, together with the sleeve and the workpiece to be machined, can form a substantially closed space.

[0041] The nozzle can be configured as a contact nozzle. In the case of a contact nozzle, the distance between the sleeve and the workpiece can be said to be zero. The distance between the substrate and the workpiece, in particular the processing distance, can be set to be greater than zero. The force caused by the part of the process gas that is guided through the connecting channel and applied to the inner surface of the sleeve, in particular the first surface portion and the second surface portion, can act in the direction of the nozzle opening or along the propagation direction of the laser beam and / or in the direction of the workpiece to be processed. In other words, the force caused can squeeze the sleeve along the propagation direction of the laser beam. The sleeve can thus be placed against the workpiece. Alternatively, the force in the direction of the nozzle opening can be provided by an elastic element between the flange area of ​​the substrate and the sleeve.

[0042] In the region between the base body and the sleeve, in particular in the storage volume, a pressure can be set by the part of the process gas which is conducted through the connecting channel, which pressure lies between the pressure in the interior volume of the base body and the ambient pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Embodiments of the present disclosure are shown in the accompanying drawings and described in detail below. In the accompanying drawings:

[0044] Figure 1 A schematic cross-sectional view showing a nozzle for a laser processing device for processing a workpiece by means of a laser beam according to a first embodiment of the present disclosure;

[0045] Figures 2A to 2C Shown from Figure 1 schematic cross-sectional views of a nozzle for a laser processing device for processing a workpiece by means of a laser beam at different distances between a base body of the nozzle and a workpiece to be processed;

[0046] Figure 3A and 3BA schematic perspective view showing a nozzle for a laser processing device according to a first embodiment of the present disclosure, the laser processing device being used to process a workpiece by means of a laser beam;

[0047] Figure 4 A schematic cross-sectional view showing a nozzle for a laser processing device for processing a workpiece by means of a laser beam according to a second embodiment of the present disclosure;

[0048] Figure 5 A schematic cross-sectional view shows a nozzle for a laser processing device for processing a workpiece by means of a laser beam according to a third embodiment of the present disclosure.

[0049] In the following, the same reference numerals are used for identical and identically acting elements unless otherwise indicated. DETAILED DESCRIPTION

[0050] Figure 1 , 2A 2C show schematic cross-sectional views of a nozzle for a laser processing device for processing a workpiece by means of a laser beam according to a first embodiment of the present disclosure. Figure 3A and 3B A schematic perspective view showing a nozzle for a laser processing device according to a first embodiment of the present disclosure, the laser processing device being used to process a workpiece by means of a laser beam;

[0051] The nozzle 10 comprises a base body 12, which can also be referred to as an "inner nozzle". The base body 12 comprises an inner volume 14. The inner volume 14 serves to guide a laser beam (not shown) and a process gas, in particular a cutting gas 16. For this purpose, the base body 12 comprises an inlet opening 18 and an outlet opening 20. The outlet opening 20 is formed at a nozzle opening or nozzle end 22 and enables a core flow 24 of the laser beam and the process gas 16 to be discharged in the direction of a process region of a workpiece 26 in order to process the workpiece. The nozzle 10 can be, for example, a cutting nozzle for a laser cutting process.

[0052] In the following, the longitudinal axis 11 of the substrate 12 is defined as the axis of the substrate 12, which extends parallel and / or coaxially with the propagation direction or optical axis of the laser beam. The longitudinal axis 11 can be an axis of symmetry, in particular an axis of rotational symmetry, of the substrate 12. The radial direction can be defined as a direction or axis perpendicular to the longitudinal axis 11. That is, the longitudinal axis 11 can be regarded as the center of a rotationally symmetric coordinate system. "Radially outward" can be referred to as a radial direction pointing away from the longitudinal axis 11. "Radially inward" can be referred to as a radial direction pointing toward the longitudinal axis 11. Accordingly, the inner radius of a component or element can be regarded as a radius that the component has in the radial direction and at the face or side facing the longitudinal axis 11, and the outer radius of a component or element can be regarded as a radius that the component has in the radial direction and at the face or side facing away from the longitudinal axis 11.

[0053] The nozzle 10 further comprises a movable sleeve 28. The longitudinal axis 28 of the sleeve may be an axis of symmetry, in particular an axis of rotational symmetry, of the sleeve 28. The longitudinal axis of the sleeve may extend substantially coaxially with the longitudinal axis 11 of the base body 12. The sleeve 28 comprises a flange region 30, which is movable in the axial direction, i.e., along or parallel to the longitudinal axis 11, along a guide region 32 of the base body 12. In other words, the sleeve 28 is movable relative to the base body 12. The sleeve 28 further comprises an annular gap region 34, which is spaced apart from the base body 12, and the sleeve optionally comprises a storage volume region 36 arranged between the flange region 30 and the annular gap region 34. The sleeve 28 may at least partially circumferentially surround the base body 12. The sleeve 28 may delimit the nozzle 10 radially outwardly or toward the surroundings. The sleeve 28 may be arranged exposed outwardly or outside the nozzle 10. In other words, the sleeve 28 may be arranged outside the base body 12. This can increase the maintenance friendliness. Therefore, the sleeve 28 can also be referred to as an "outer sleeve".

[0054] The annular gap region 34 of the sleeve 28 forms an annular gap 38 together with the base body 12, through which the process gas 16 is discharged as an annular flow 40. The storage volume region 36 forms a storage volume 42 connected to the annular gap 38 together with the base body 12. In other words, the annular gap 38 is arranged between a first region of the base body 12 and the annular gap region of the sleeve 28, and the storage volume 42 is arranged between a second region of the base body 12 adjacent to the first region and the storage volume region 36 of the sleeve 28. The annular gap 38 can be designed in particular in the form of a cylindrical ring, and / or the inner surface 29 of the sleeve 28 in the annular gap region 34 and / or the annular gap region 34 can be designed in the form of a cylinder. The outer surface of the base body 12 or the wall of the base body 12 can be designed conically or cylindrically in the region between the guide region 32 and the nozzle opening 22. The outer surface of the wall of the base body 12 has an equal distance from the longitudinal axis 12 of the base body in the guide region 32 and is preferably cylindrical.

[0055] The base body 12 has at least one connecting channel 44, which connects the inner volume 14 to the area or volume between the base body 12 and the sleeve 28. According to the embodiment shown, at least one connecting channel 44 connects the inner volume 14 to the storage volume 42, but the present disclosure is not limited to this. As shown, the at least one connecting channel 44 is arranged in the axial direction between the guide area 32 and the nozzle opening 22.

[0056] like Figure 1 As shown in the figure, at least one connecting channel 44 includes four individual connecting channels 44, which are arranged regularly or equally distributed in the circumferential direction of the inner volume 14, but the present disclosure is not limited to this. At least one connecting channel 44 is basically cylindrical. At least one connecting channel 44 can be particularly configured as a hole.

[0057] At least one connecting channel 44 serves to guide a portion 46 of the process gas 16 from the inner volume 14 into the storage volume 42 and then into the annular gap 38, from which it is discharged as an annular flow 40 in the direction of the workpiece 26. In other words, the process gas 16 is fed into the inner volume 14 of the base body 12 through the feed opening 18. A portion of the process gas 16 is discharged as a core flow 24 through the discharge opening 20 from the nozzle opening 22 of the base body 12, and another portion 46 of the process gas 16 is discharged as an annular flow 40 from the annular gap 38 between the base body 12 and the annular gap region 34 of the sleeve 28. Both the core flow 24 and the annular flow 40 reach the workpiece 26 to be processed coaxially with the laser beam. The annular flow 40 thus surrounds the core flow 24.

[0058] In the region between the base body 12 and the sleeve 28, in particular in the storage volume 42, a pressure is set which is between the pressure in the inner volume 14 and the ambient pressure. If a nearly uniform pressure is assumed in this region, the induced force acting on the sleeve 28 can be set by selecting the surface ratios of the inner surface 29 of the sleeve 28. The aim here is to generate an induced force acting in the direction of propagation of the laser beam, i.e. in the direction of the workpiece 26, so that the sleeve 28 is pressed in the direction of the workpiece 26 and rests against the workpiece 26. That is, the nozzle 12 can be designed as a contact nozzle.

[0059] It is therefore necessary that the surface portion of the inner surface 29 of the sleeve 28 acting in the propagation direction of the laser beam under gas pressure is larger than the surface portion of the inner surface 29 acting opposite to the propagation direction of the laser beam. This is the case, for example, when the inner diameter of the flange area 30 is larger than the inner diameter of the annular gap area 34. For example, the surface portion of the inner surface 29 of the sleeve 28 extending perpendicularly to the axial direction and located in the axial direction on the side of the connecting channel 44 facing the nozzle opening 22 (also referred to as the "first surface portion" 29a) can be larger than the surface portion of the inner surface 29 of the sleeve 28 extending perpendicularly to the axial direction and located in the axial direction on the side of the connecting channel 44 facing away from the nozzle opening 22 (also referred to as the "second surface portion" 29b). However, the present disclosure is not limited to this.

[0060] like Figures 2A to 2C As shown in , the sleeve 28 can be moved relative to the base body 12 in the axial direction, i.e. along the longitudinal axis 11 of the base body 12. In other words, the sleeve 28 can be moved in the axial direction relative to the base body 12. Preferably, at least one connecting channel 44 opens into the storage volume 42 for each arbitrary position of the sleeve 28 relative to the base body 12. As in Figures 2A to 2C As can be seen in FIG. 4 , the storage volume 42 is of different sizes in different positions of the sleeve 28 , but the present disclosure is not limited thereto.

[0061] In addition to the movement in the axial direction, the sleeve 28 can be tilted relative to the base body 12. In other words, the sleeve 28 can be tilted relative to the base body 12 with the flange region 30.

[0062] The flange area 30 of the sleeve 28 extends radially inwardly toward the guide area 32 of the base body 12 and surrounds a portion of the guide area 32. The flange area 30 and / or the guide area 32 can be cylindrically configured. The flange area 30 can in particular have a cylindrical annular flange, a flange or a cylindrical annular projection, but the disclosure is not limited thereto.

[0063] As shown, the inner radius of the flange area 30 is greater than the outer radius of the guide area 32. That is, the flange area 30 is spaced apart from the guide area 32. That is, a gap 48 is formed between the flange area 30 and the guide area 32. The gap 48 can be constructed in a cylindrical annular shape, but the present disclosure is not limited to this. During the operation of the nozzle 10, the flange area 30 and the guide area 32 form a gap seal. This enables frictionless or low-friction movement of the sleeve 28 relative to the base body 12, such as linear movement and tilting movement. Alternatively, a gap fit can be constructed between the flange area 30 and the guide area 32.

[0064] The guide region 32 further comprises a radially outwardly protruding projection 52, which is configured on the end of the guide region 32 facing the nozzle opening 22 and which limits the axial movement of the sleeve 28 along the longitudinal axis 11 of the base body 12. For this purpose, the outer radius of the projection 52 is greater than the inner radius of the flange region 30 of the sleeve 28. That is, the sleeve 28 is arranged on the base body 12 in such a way that the flange region 30 of the sleeve 28 together with the projection 52 limits the movement of the sleeve 28 in the axial direction. That is, the projection 52 prevents the sleeve 28 from slipping off in the direction of the workpiece 26. In the illustrated embodiment, the projection 52 is configured as a flange, in particular a cylindrical annular flange, a flange or a projection, but the present disclosure is not limited thereto.

[0065] In one embodiment, the base body 12 has a fixing element 50. The fixing element 50 can be releasably connected to a wall 54 of the base body 12 surrounding the inner volume 14 of the base body 12. The releasable connection (not shown) can be realized as a thread, a latch, by means of a screw or the like. The fixing element 50 can have a projection 52. Optionally, the fixing element 50 can have at least a portion of the guide area 32.

[0066] In one embodiment, the sleeve 28 includes a first portion 56 and a second portion 58. The first portion 56 includes the flange area 30, and the second portion 58 includes the annular gap area 34. The two portions 56 and 58 can be releasably connected to each other, but the present disclosure is not limited to this. The releasable connection (not shown) can be achieved by threads, latches, bolts, or the like. In other words, the sleeve 28 can be implemented separately in the middle area.

[0067] The nozzle 10 is preferably assembled in such a way that the fixing element 50 and the first part 56 of the sleeve 28 are first inserted into each other. Then the combination is connected to the base body 12, in particular screwed. Finally, the second part 58 of the sleeve 28 is connected to the first part 56, in particular screwed. During the operation of the nozzle 10, in particular during the laser processing process by means of a laser processing device including the nozzle 10, the second part 58 of the sleeve 28 is worn because it is guided onto the workpiece 26 and is located closest to the process area and is thus most strongly affected by process emissions. Through the present invention, this second part 58 can be quickly replaced without having to disassemble the entire nozzle 10. However, it is also possible to replace all other parts of the nozzle 10. In addition, the base body 12 can also be implemented in at least two parts, wherein the parts are also detachably connected to each other.

[0068] The nozzle 10 does not necessarily have to have a fixing element 50. Likewise, the sleeve 28 can also be constructed in one piece. In an embodiment without a fixing element, the material forming at least one part of the sleeve 28 or at least the first part 56 of the sleeve 28 can be an elastic material. The sleeve 28 can then be put onto the projection 52 when it is mounted on the base body 12. Accordingly, it is also possible to make only the flange area 30 of the sleeve 28 from an elastic material. Alternatively or additionally, the projection 52 can also be made of an elastic material.

[0069] The sleeve 28 can be made of an insulating material. For example, ceramic, polyetheretherketone or another high-temperature-resistant plastic can be selected here. When a capacitive distance sensor is used to determine the distance between the laser processing device, in particular the base body 12, and the workpiece 26, the processing distance between the workpiece 26 and the laser processing device or the base body 12, which can be made of copper, for example, can be measured or adjusted, without the measurement being affected by the presence of the sleeve 28. The maximum processing distance, which also achieves sealing of the cutting gap relative to the surrounding environment, is achieved by the sleeve 28 protruding as far as possible from the base body 12 until the sleeve 28 rests on the projection 52 of the fixing element 50. Figure 2A 2B and 2C show the nozzle 10 with a workpiece 26 and a processing distance between the substrate and the workpiece of 0.5 mm, 1.0 mm and 1.5 mm respectively.

[0070] Like the base body 12, it is also made of copper. However, in order to prevent the fixing element 50 from cold welding with the base body 12, it would be advantageous to use another metallic material, such as stainless steel. This also ensures that the individual parts can be replaced multiple times.

[0071] Figure 4A schematic cross-sectional view shows a nozzle for a laser processing device for processing a workpiece by means of a laser beam according to a second embodiment of the present disclosure. Only the differences from the nozzle 10 according to the first embodiment of the present disclosure are described below.

[0072] like Figure 4 As shown in the figure, at least one connecting channel 44 is designed as an elongated hole. At least one connecting channel 44 preferably opens at least partially into the storage volume 42 for each position of the sleeve 28 relative to the base body 12. By using the elongated hole, the flow through the nozzle 10 is increased while maintaining the same pre-pressure. In addition, the volume flow portion in the annular flow 40 is increased.

[0073] Figure 5 A schematic cross-sectional view of a nozzle for a laser processing device for processing a workpiece by means of a laser beam according to a third embodiment of the present disclosure is presented. Only the differences from the nozzle 10 according to the first embodiment of the present disclosure are described below.

[0074] Figure 5 The nozzle shown in the figure additionally has a wear ring 60. The wear ring 60 is constructed on the end of the sleeve 28 facing the workpiece in the axial direction of the sleeve 28. The wear ring 60 can be placed on the sleeve 28 by crimping, screwing, bonding or clamping. The wear ring 60 can be placed on the workpiece 26 during the processing of the workpiece 26. In other words, the wear ring 60 is the following element of the nozzle 10, which contacts the workpiece during processing. The wear ring 60 is therefore the following element of the nozzle 10, which is most subject to wear. When the wear ring 60 is constructed to be removable from the sleeve 28, it can be easily and simply replaced when necessary. The wear ring 60 can be made of brass. It is possible that the wear ring 60 is particularly wear-resistant, high-temperature-resistant and with a high reflectivity.

[0075] The nozzle according to the disclosed embodiments enables a portion of the process gas to be conducted from the inner volume of the base body to the region between the base body and the sleeve by means of the connecting channel in order to generate an annular flow of the process gas coaxially to the laser beam in addition to the core flow.

[0076] The nozzle according to the embodiment of the present disclosure also has a guide area on the base body for guiding the movable sleeve, which is arranged above the connecting channel in the axial direction of the base body or on the side of the connecting channel facing away from the nozzle opening, so that the connecting channel is located between the guide area and the nozzle opening. This increases the distance between the guide area and the nozzle opening or the distance between the guide area and the process area, in which process emissions are generated. This can reduce or prevent the mixing of process emissions into the nozzle or the area between the base body and the sleeve, so that the mobility of the sleeve relative to the base body is maintained.

[0077] The nozzle according to an embodiment of the disclosure has a sleeve which is constructed in multiple parts. As a result, the parts that are subject to wear can be easily accessed and replaced easily and simply when necessary. In this case, all other parts of the nozzle or sleeve can continue to be used. This further increases the maintenance friendliness of the nozzle. The releasable connection of the two parts can be achieved by means of a thread, a latch, a bolt or the like.

[0078] The nozzle according to the disclosed embodiment has a sleeve which can be tilted relative to the base body, so that the sleeve can be deflected to unevenness on the workpiece and thus the cutting gap is sealed from the surroundings even if the workpiece surface is uneven.

[0079] The nozzle according to the disclosed embodiment has a gap seal between the flange area of ​​the sleeve and the guide area of ​​the base body. This can reduce or avoid friction between the sleeve and the base body when the sleeve moves. The gap seal also enables better tiltability of the sleeve relative to the base body.

[0080] The nozzle according to an embodiment of the present disclosure has a sleeve which at least partially circumferentially surrounds the base body. The sleeve can in particular delimit or limit the nozzle radially outward or toward the surroundings. In other words, the sleeve can be arranged outside the base body. This improves the maintenance friendliness of the nozzle.

[0081] Reference numerals list

[0082] 10 Nozzle

[0083] 11 Longitudinal axis

[0084] 12 Matrix

[0085] 14 Internal volume

[0086] 16 Process Gas

[0087] 18 Input opening

[0088] 20 Output opening

[0089] 22 Nozzle

[0090] 24 Core Stream

[0091] 26 Workpieces

[0092] 28 Sleeve

[0093] 29 Inner surface of sleeve

[0094] 29a First side part

[0095] 29b Second side part

[0096] 30 Flange area

[0097] 32 Guide area

[0098] 34 Annular gap area

[0099] 36 Storage volume area

[0100] 38 Annular gap

[0101] 40 Annular Flow

[0102] 42 Storage capacity

[0103] 44 Connection Channels

[0104] 46 Process gas section

[0105] 48 Gap

[0106] 50 Fixing elements

[0107] 52 protrusion

[0108] 54 wall

[0109] 56 First part of the sleeve

[0110] 58 Second part of the sleeve

[0111] 60 Wear ring.

Claims

1. A nozzle (10) for a laser processing device for processing a workpiece (26) by means of a laser beam, the nozzle (10) comprising: a base body (12) having a longitudinal axis (11), wherein the base body (12) has an inner volume (14) for guiding the laser beam and the process gas (16) and a nozzle opening (22) having an output opening (20) for outputting a core flow (24) of the laser beam and the process gas (16), a movable sleeve (28) having a collar region (30) which is movable along a guide region (32) of the base body (12) and an annular gap region (34), the collar region being movable along a guide region (32) of the base body (12), the annular gap region being spaced apart from the base body (12) and forming, together with the base body (12), an annular gap (38) for discharging an annular flow (40) of the process gas (16), wherein the flange region (30) extends radially inwardly toward a guide region (32) of the base body (12) and surrounds a portion of the guide region (32), wherein radially inwardly refers to a radial direction pointing toward a longitudinal axis (11) of the base body (12), The guide area (32) is designed in the form of a cylindrical ring, and The base body (12) has at least one connecting channel (44) which connects an inner volume (14) of the base body (12) to an area between the base body (12) and the sleeve (28) in order to conduct a portion (46) of the process gas (16) into the annular gap (38), wherein the sleeve (28) comprises a first part (56) and a second part (58) which are releasably connectable to one another, wherein the first part (56) comprises the flange area (30) and the second part (58) comprises the annular gap area (34), wherein the at least one connecting channel (44) is arranged between the guide area (32) and the nozzle opening (22), The sleeve (28) further comprises a storage volume region (36) arranged between the flange region (30) and the annular gap region (34), wherein the storage volume region together with the base body (12) defines a storage volume (42) connected to the annular gap (38), The inner radius of the sleeve (28) in the storage volume area (36) is greater than the inner radius of the sleeve (28) in the annular gap area (34) and / or the inner radius of the sleeve (28) in the flange area (30).

2. The nozzle (10) according to claim 1, wherein: The sleeve (28) is movable along the longitudinal axis (11) of the base body (12).

3. The nozzle (10) according to claim 1 or 2, wherein: The sleeve (28) can also be tilted relative to the base body (12).

4. The nozzle (10) according to claim 1 or 2, wherein: The sleeve (28) has an inner surface (29) which is spaced apart from the base body (12) and is designed such that a force caused by the process gas pressure in the region between the sleeve (28) and the base body (12) acts on the sleeve (28) in the direction of the nozzle opening (22).

5. The nozzle (10) according to claim 1 or 2, wherein: The inner radius of the flange area (30) is greater than the outer radius of the guide area (32) of the base body (12), and / or the flange area (30) is spaced apart from the guide area (32), and / or the flange area (30) and the guide area (32) form a gap seal.

6. The nozzle (10) according to claim 1 or 2, wherein: The base body (12) has at least one radially outwardly projecting projection (52), which is formed at the end of the guide region (32) facing the nozzle opening (22) and which limits the movement of the sleeve (28) about the longitudinal axis (11) of the base body (12).

7. The nozzle (10) according to claim 6, wherein: The base body (12) has a fixing element (50) which includes the guide region (32) and / or the projection (52), wherein the fixing element (50) can be releasably connected to a wall (54) of the base body (12) surrounding the inner volume (14).

8. The nozzle (10) according to claim 1 or 2, wherein: The basic body (12) has a cylindrical outer shape in the guide region (32).

9. The nozzle (10) according to claim 7, wherein: At least the flange region (30) and / or the first portion (56) of the sleeve (28) consists of an elastic material, and / or the base body (12) comprises copper, and / or the fixing element (50) comprises stainless steel or copper.

10. The nozzle (10) according to claim 1 or 2, wherein: The sleeve (28) and / or the flange region (30) of the sleeve (28) are arranged on the nozzle in an outwardly exposed manner, and / or wherein: The volume flow of the process gas in the nozzle is limited only by the base body (12) and the sleeve (28).

11. A laser processing device for processing a workpiece (26) by means of a laser beam, comprising: - processing head, and - A nozzle (10) according to any one of the preceding claims 1 to 10, which is arranged on the processing head.

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