DE8337305U1 - Device for cutting workpieces with a laser beam - Google Patents

Description

Patent Attorneys · European Patent Attorneyi Bremen-MUncben *

MeiMMt * Bölte, Hollenllee 73.D-2800 Bremen

Applicant;

BIAS research and Development laboratory for

applied beam technology GmbH

irmlandstrasse 59 2820 Bremen 71

Htm Meistner Dipl.-Ing, (M * 1980) Erich Bolt «· Dipl.-Ing. Dr. Eugea Popp ■ Dipl.-Ing., Dipl.-WirUeh.-Ing. * Wolf E. Sajda Dipl. <Phyi. * Dr. Tarn v. Bttlow Dipl.-Ing., Dipl'Wtrtsch.-ing, * OFFICE BREMEN

HoUerail66? 3 D-2800 Bremen 1

Telephone: (0421) 342019 Tetegrams: PATMBlS BREMEN Telex: 246157 meibod

You sign
Your Kl.

Ou letter from Your letter of

Our mark Ourref.

Dituffl Dite

BIA-14-DE

December 23, 1983/9119

Device for cutting workpieces with a laser beam

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The invention relates to a device for cutting workpieces by means of a laser beam according to the preamble of claim 1.

With energy sources of high power density, metallic materials in particular can be transported at high speed cut, this is usually done using high-power energy sources like focused laser beams, but also electron beams are used. Because of the high power density COo laser beams are special for cutting workpieces suitable.

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The material usually only has a width of

1/10 mm cutting joints must either be completely cut with clean cutting surfaces burn or oxidize or evaporate completely.

In any case, it must be prevented that condensed material forms in the thin cutting kerf.

It is problematic to comply with the aforementioned conditions when working at high cutting speeds is to be or sheets are to be cut with great thickness. To get an education even under these circumstances Avoiding condensed or liquid material in the cutting gap as completely as possible becomes a Cutting gas jet on the workpiece surface, especially

Ib re directed the cutting gap. When laser cutting, in which the material to be removed from the joint either burns or oxidizes, is used as cutting gas in the Usually oxygen is supplied. In contrast, with laser sublimation cutting, argon is supplied as a cutting gas for evaporation of the joint material. In this latter case, the cutting gas, namely argon, is used at the same time Protective gas. Depending on the application, gases other than oxygen and argon can also be used as cutting gas .

With regard to the supply of the cutting gas, different devices for laser cutting are known. In the simplest Trap, the cutting gas is passed through one of the iichneiddüse to the exit of the focused laser beam independent device led to the workpiece or to the cutting joint. Such devices have significant disadvantages when complicated cuts, for example curve or corner cuts, are to be carried out. Problems also occur with relatively thick workpieces.

To avoid this disadvantage, further devices are

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known in which the cutting gas within the Cutting nozzle is guided to the laser beam. The cutting gas then emerges from the together with the laser beam Cutting nozzle, through a common opening. A disadvantage of this known device due to of the focal point of the laser beam lying outside the cutting nozzle has a relatively large opening a relatively high welding gas consumption. This occurs due to the relatively large opening in the cutting nozzle Cutting gas with a thick gas jet out of the cutting head. As a result, the exit velocity There are natural limits to the gas jet, as a result of which the impulse effect of the cutting gas is lost to a large extent goes. This leads to unclean cutting joints, especially at high cutting speeds.

Finally, to improve the laser cutting devices described above, those with separate ones are used Known cutting gas outlet openings having cutting gas nozzles. The latter are either cylindrical or designed to taper towards their openings, usually several cutting gas nozzles are concentric arranged around the opening for the exit of the laser beam in the cutting head. But it can also be a single one The cutting gas nozzle can be arranged as a ring nozzle concentrically to the laser beam in the cutting head. However, the latter is in Difficult to manufacture with regard to a gap width that is the same on all sides or requires a very precise adjustment the individual parts of the cutting head used to form the annular gap.

However, the performance of these known devices is limited. The cutting nozzles only allow a limited exit speed of the cutting gas. This is a maximum of 1.2 mach. At higher gas exit speeds the gas flow is no longer reliable

controllable, which has the effect of an increasingly diffuse gas jet. The cutting gas arrives is no longer targeted in the cutting gap and also no longer has sufficient momentum to be able to withstand high Cutting speeds and large sheet metal thicknesses to ensure reliable separation of the workpiece with clean cutting edges.

The invention is therefore based on the object of providing a laser cutting device while avoiding the disadvantages mentioned at the beginning to create an optimal cutting gas supply with a high cutting performance enables complicated cutting processes.

To achieve this object, the invention has the characterizing features of claim 1. Due to the enlargement of the cross section of the cutting gas nozzles towards the cutting gas outlet openings, the welding gas jet emerging from the same remains essentially intact even at very high flow speeds. Flow velocities in or at the opening of the gas outlet nozzles of more than 1 mach are possible without the jet characteristics of the cutting gas being lost after leaving the gas outlet openings of the cutting gas nozzles. As a result, cutting gas jets can act on the cutting gap with an energy potential that is sufficient for high gas speeds and large sheet metal thicknesses.

The gas outlet nozzles are expediently in the

Cutting nozzle arranged concentrically around the (central) laser beam. The cutting gas jets emerging from the cutting head thereby evenly surround the laser beam.

In a particularly advantageous embodiment of the invention are concentric around the laser beam

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arranged gas outlet nozzles arranged obliquely in the cutting head. Preferably, all of the gas outlet nozzles have an equal inclination, which is chosen such that the cutting gas jets emerging from the cutting head meet unite roughly on the longitudinal axis of the focused laser beam. The intersection of the cutting gas jets on the The longitudinal axis lies in an advantageous embodiment of the invention at a slight distance in front of the focal point of the laser beam. With such a configuration of the The device according to the invention is a union of Cutting gas jets with the laser beam in such a way that behind the intersection of the laser beam with the Cutting gas jets a common, approximately identically directed beam is created, with the cutting gas forming the laser beam enveloped. Alternatively, the merging point of the gas beams with the laser beam can also be directly in the focal point of the Laser beam or behind the same.

The distance between the lower edge of the cutting nozzle and the

The surface of the workpiece should expediently be selected so that the cutting gas jets are aligned with the laser beam meet at a distance from the surface of the workpiece. As a result, a united already occurs in the cutting gap Beam, which creates clean, almost parallel cutting surfaces even at high cutting speeds. Due to the high gas velocity, the gas jets combined with the laser beam clear the molten or Evaporated or condensed material reliably from the cutting kerf, even with relatively thick workpieces.

By uniting the individual rays in front of the workpiece surface it is also possible to perform almost all imaginable curve cuts. If necessary, the Cutting nozzle also be inclined to the workpiece surface, whereby inclined to the same cutting surfaces arise.

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According to a further proposal of the invention, the gas outlet nozzles in the cutting head designed as Laval nozzles, namely with a frustoconical shape. The larger diameter the opening of the Laval nozzle thus forms the gas outlet opening in the cutting nozzle. The Laval nozzles allow cutting gas flow speeds of up to 2 mach. For example, a Laval nozzle having the dimensions according to dependent claim 10 allows a flow rate of the gas of 1.8 mach.

In a particularly advantageous embodiment of the Invention are three gas outlet nozzles designed as Laval nozzles evenly with respect to one concentric the laser outlet opening in the cutting nozzle arranged pitch circle diameter distributed. Preferably all have three Laval nozzles of the same dimensions. Due to the three a diameter of the gas outlet openings of only 1 mm having Laval nozzles, the laser cutting device according to the invention is characterized by a minimal

Cutting gas consumption.

The Laval nozzles are supplied with cutting gas via a feed bore. The latter in turn become common supplied with cutting gas by a circumferential ring groove.

The annular groove is in an advantageous embodiment of the invention between two parts of the cutting nozzle, namely a receiving cylinder and a nozzle insert. The cutting nozzle constructed in this way is characterized by a compact one, despite the feed channels for the gas outlet nozzles

Construction from.

An embodiment of the invention is based on the following the Figures 1-6 of the drawing explained in more detail.

Show it:

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1 shows a schematic laser cutting device in a perspective illustration;

2 shows a vertical section through the longitudinal center plane of a cutting head of the laser cutting device ;

Fig. 3 is a 90 ° offset side view of the

Cutting head according to FIG. 2; IO

4 shows a central vertical section through a cutting nozzle of the cutting head;

FIG. 5 shows a detail IV according to FIG. 4, namely a gas outlet nozzle on an enlarged scale;

and

FIG. 6 shows a view of the cutting nozzle according to FIG. 4

towards VI.
20th

1 clearly shows the basic structure of the laser cutting device according to the invention. As an energy source a high power laser is used here, namely, a C0 ₂ laser beam 10. At the output of the C0 ₂ laser 10 is here a telescope 11. The latter is connected via a conduit 12 with a deflecting mirror. 13 This deflects the laser beam arriving through the protective tube 12 from the horizontal to a vertical beam direction. The laser beam finally reaches the cutting head 15 through another protective tube 14, which in this embodiment is variable in length. The laser beam is focused in this direction, the "" in "der Fig.2

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with the reference number 16 is designated. The cutting head 15 a cutting nozzle 17 is arranged downstream of the exit of the now converging laser beam 16. By The laser beam 16 passes through the cutting nozzle 17 from the device in the direction of the workpiece to be cut 18 out.

In this exemplary embodiment, the cutting device has only one degree of freedom, namely that of the cutting head is only in the vertical direction, i.e. perpendicular to the surface of the workpiece 18 is movable. In the horizontal plane, namely to accomplish the cutting feed, is in this embodiment the workpiece 18 can be moved. This cannot be done, for example, by one in the figures shown work table happen on which the loosely resting or clamped workpiece 18 can be moved in preferably opposite directions.

Alternatively, however, the workpiece 18 can also have three degrees of freedom, d. H. can be moved in both the horizontal and vertical planes. The workpiece 18 also be firmly attached to a workpiece carrier and the welding device, in particular the cutting head in three Directions can be moved. For example, in addition to the variable-length protective tube 14, for this purpose of the horizontal protective tube 12 is designed to be variable in length be. If necessary, either the cutting head 15 or the entire device on an arm of a Robot can be arranged. The cutting head 15 can then in an almost unrestricted manner with respect to the workpiece 18 processes can be used to create any cutting course.

The cutting head 15 is shown in detail in FIG. Accordingly, this has an elongated housing 19 with a square cross-section. In the center of the housing 19 is a longitudinal, irregular circular through hole

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20 arranged. The opposite end faces 21 of the housing 19 are each provided with a flange Lid 22 closed. The latter has a circular one Cross-section on and has on opposite sides Two tabs 23. With the tabs 23, the DeGkel 22 are in each case by two screws 24 in the end faces 21 of the housing 19 screwed. The relative position of the cover 22 or the tabs 23 with respect to the housing 19 is - as 3 shows - chosen so that the screw gen (screws 24) in diagonally opposite corners the square end faces 21 of the housing 19 lie.

On the inner sides of the cover 22 directed towards the end faces 21 of the housing 19, there are circular centering lugs 25 arranged. The diameter of the centering lugs 25 are selected in such a way that they fit tightly into the through-hole 20 of the housing 19. The lids 22 are centered in this way with respect to the housing 19 with respect to its longitudinal center axis 26.

A circular entry opening 28 for the laser beam into the housing 19 of the cutting head 15 is in one above lying, horizontal wall of the housing 19 arranged, in an end region of the same. To exit of the laser beam 16 from the housing 19, a total of three circular exit bores 29 are provided. One the outlet bores 29 are located in the lower, horizontal wall of the housing 19, while the other two Outlet bores 29 are arranged in opposite, upright walls of the housing 19. The exit holes 29 are located in a vertical plane in the area of the one opposite the inlet opening 28 End area of the housing 19. The outlet bores 29 are accordingly opposite the inlet opening 28 in the longitudinal direction of the cutting head 15 offset.

The Z ^ shaped deflection of the laser beam 16 within the

Cutting head 15 takes place through two (deflection) mirrors of circular cross-section. The inlet opening 28 of the The laser beam 16 into the housing 19 is a deflecting mirror 30 with a flat, at 45 ° to the longitudinal center axis 26 of the cutting head 15 is assigned to extending mirror surface 31. In this way a diversion takes place of the laser beam 16 entering the cutting head 15 vertically in a horizontal direction thereof. Of the horizontal laser beam 16 lies with its central axis on the longitudinal central axis 26 of the housing 19. From the horizontal the laser beam 16 is finally deflected again into a vertical position by a second mirror, namely a focusing mirror 32 also having a circular cross-section. In contrast to the opposite Deflecting mirror 30, the focusing mirror 32 has a convexly curved, parabolic mirror surface As a result, the laser beam 16 is focused. A chord through the curved mirror surface 33 of the focusing mirror 32 lies here - as in the case of the deflecting mirror 30 - in a 45 ° direction to the longitudinal center axis 26 of the housing 19. As a result, depending on the position of the focusing mirror 32, the focused laser beam 16 can emerge from the housing 19 of the cutting head 15 through one of the exit bores 29 .

The mirrors (deflecting mirror 30 or focusing mirror 32)

are arranged with their rear sides in front of the inner end faces 27 of the centering lugs 25 on the covers 22. The attachment of the mirror to the covers 22 is done by a screw 35 in the Longitudinal central axis 26 lies in such a way that the longitudinal axes of the mirrors also lie on longitudinal central axis 26.

The deflection mirror 30 and the focusing mirror 32 have approximately the same diameter, which is slightly smaller than the diameter of the through hole 2Q, in the housing

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are. In this way arises between the housing 19 and the mirrors 30, 32 a circumferential gap 36. This prevents the mirrors 30, 32 from jamming in the housing 19, if these parts are made from different materials due to the resulting different Unevenly expand the coefficient of thermal expansion when the cutting head heats up.

At least the focusing mirror 32 is in the housing 19

90 ° angle sections can be rotated. In this way, the focused laser beam 16 through one of the three in different Exit bores 29 lying on the planes emerge from the housing 19. In Fig. 2 is a twofold Deflection of the laser beam 16 in a single, vertical Plane shown, d. H. the focused laser beam 16 emerges from the lower, horizontal exit bore 29 of the housing 19. By rotating the Cover 22 with the focusing mirror 32 arranged thereon by 90 °, the focused laser beam 16 can with certain Use cases through the upright outlet bores 29, that is to say in the horizontal direction, emerge from the housing 19. To screw the cover 22 in such a position relative to the housing 19, its end face 21 has, as 3 shows a total of four threaded blind bores 37, where depending on the relative position of the focusing mirror 32 and of the cover 22 two diagonally opposite threaded blind holes 37 from the screws 24 for fastening the Find cover 22 on the housing 19 use.

In this embodiment, the cutting head is 15

coolable, preferably with cooling water. For this purpose, the housing 19 has cooling bores, which are only partially shown 38, which form a closed circuit here, which is supplied and / or connected by two cooling water connections 39. is disposed of.

The attachment of the cutting head 15 to the variable-length In the present case, the protective tube 14 of the device takes place through two connections. In addition

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the protective tube 14 has at the end two collars 40 which are arranged at a distance from one another and which have a circumferential groove 41 on the protective tube 14. Corresponding to the groove 41 and the collar 40 are rtes on the horizontal, upper wall Housing 19 spaced transversely from one another, L-shaped Sliding blocks 42 arranged. The latter each have a nose 43, the areas of the assigned in it Groove 41 engages protective tube 14. In the longitudinal direction of the sliding blocks 42, the protective tube 14 is opposite the same can be fixed by means of suitable locking devices, for example clappers.

In the same way, namely also by engaging in a groove 44 sliding blocks 45, the cutting nozzle 17 is one the three outlet bores 29 in the housing 19 of the cutting head 15 to be assigned. In the present embodiment According to FIG. 2, the cutting nozzle 17 is assigned to the lower, horizontal outlet bore 29. The two others, Upright support holes can be used to protect the interior of the cutting head 15 can be closed with blind flanges not shown in the figures.

Figure 4 shows a single cutting nozzle. In the present case, this is designed in two parts, namely, it sits down from an outer receiving cylinder 46 and a nozzle insert 47 to be arranged in the same. The receiving cylinder In this exemplary embodiment, 46 has two on its outer, upper edge - like the protective tube 14 spaced apart collar 48 which form the groove 44 with which the cutting nozzle 17 between the parallel sliding blocks 45 on the housing 19 of the cutting head 15 is slidable. The end face directed towards the housing 19 50 of the cutting nozzle 17 has a locking projection 49. This has parallel, upright guide surfaces 51. These adjust the cutting nozzle 17 with respect to the housing 19 by using a correspondingly designed

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th recess 52 with corresponding guide surfaces 53 is assigned. An adjustment is made in this way of the cutting nozzle 17 cannot be rotated and cannot be displaced in the longitudinal direction of the housing 19.

Inside, the receiving cylinder 46 has a cylindrical one Guide area 54 and a constriction adjoining it at the top with an internal thread 55. The outer jacket 56 of the nozzle insert 47 is designed accordingly. This shows one for the most part cylindrical outer jacket 56, the Oberberiüch a Undercut mi »: has an external thread 57. The dimensions of the internal thread 55 of the receiving cylinder £ 6 on the one hand and the external thread 57 of the nozzle insert 47 on the other hand are dimensioned such that through the thread both parts of the cutting nozzle 17 can be screwed together. The (longer) guide area 54 in the receiving cylinder 46 serves to guide the nozzle insert 47 precisely along its outer jacket 56.

Inside, the nozzle insert 47 has a frustoconical shape Through hole 59. The latter tapers towards the laser outlet opening 58 of the nozzle insert 47, that is to say towards the Underside of the cutting nozzle 17 out. The inclination of the tapered through hole 59 is chosen so that their Walls run approximately parallel to the focused laser beam 16.

Around the through hole 59 for the laser beam 16 are in the nozzle insert 47 of the cutting nozzle 17 in this embodiment three gas outlet nozzles 60 arranged at an angle. All three gas outlet nozzles 60 here have the same inclination and same dimensions. You are on a common pitch circle 61, which is shown in Fig. is shown. On the pitch circle 61, the gas outlet nozzles 60 are evenly distributed, namely each with approximately

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120 ° offset to each other. The inclination of the gas outlet nozzles 60 to a longitudinal axis 62 of the nozzle insert 47 is here about 30 °. So that the gas outlet opening of the gas outlet nozzles 60 is on the underside of the nozzle insert 47 runs at right angles to the longitudinal axis 62 of the gas outlet nozzles 60, the lower edge of the nozzle insert 47 is with a bevel 63 running around the circumference. The latter points opposite the longitudinal axis 62 of the nozzle insert 47 an incline of about 60 °.

The design of a gas outlet nozzle 60 can be seen clearly from FIG. 5. The one shown in this figure The gas outlet nozzle 60 is designed as a Laval nozzle. Therefore the gas outlet nozzle 60 has a cylindrical one

Area 64 inside the nozzle insert 47 to which

a frustoconical end area 65 adjoins the nozzle outlet f. This kegelstumpförtige end \ 65 widens starting from the diameter of the cylindrical portion 64 to a larger diameter for gas

outlet opening 66 out. ;

The dimensions of the gas outlet nozzle 60 in the present Execution example) are as follows:

The cylindrical region 64 has a length of 5 mm and a diameter of 0.7 mm. The same length, namely also 5 mm, has the frustoconical end \ area on 65th It widens from the diameter of the cylindrical area 64 by 0.7 mm to 1.0 mm towards the gas outlet opening 66 in the cutting nozzle 17. The derar- | gas outlet nozzle 60 designed as a Laval nozzle allows a gas flow rate of about 1.8 mach. :

The nozzle insert 47 points to the supply of each gas outlet nozzle 60 a feed bore 67 with cutting gas. The latter is cylindrical with a diameter of about 3 mm and opens out from the cylindrical

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Outer jacket 56 of the DUsen insert 47 in the cylindrical area 64 of the gas outlet nozzles 60. The three feed bores 67 in the nozzle insert 47 are supplied by a Circumferential annular groove 68 arranged in the receiving cylinder 46. In the present case, the latter is formed by a groove in the receiving cylinder 46 horizontal supply bore 69 fed. The supply bore 69 can - as here - a have continuous internal thread for receiving connection nipples, not shown in the figures, for a Feed line of the cutting gas.

At a distance from the annular groove 68, on each side thereof, there is a groove 70 in the guide region 54 of the receiving cylinder 46 arranged. The grooves 70 each receive a sealing ring 71 for sealing the annular groove 68.

The cutting nozzle 17 described above enables the three to be brought together, as can be seen in FIG with the reference numeral 75 designated cutting gas jets with the laser beam 16 at the intersection 72, which in the present Embodiment lies at a slight distance above a focal point 73 of the laser beam 16. The latter lies here approximately in the plane of the surface of the workpiece 18, but can also be slightly lower, so already in the cutting gap 74 *

Meissner & Bolte patent attorneys

Applicant;

BIAS research and development laboratory for applied beam technology GmbH
Erm ¹ .andstrasse 59

2820 Bremen 71

Bremen, December 23, 1983

9119

List of reference symbols

10 C0 ₂ laser ·· · · ■
• · · ti 39 ■ SI · 1 »
XfI Cooling water connection 11th telescope 40 collar 12th Protection tube 41 Groove 13th Deflection mirror 42 Sliding block 14th Protection tube 43 nose 15th Cutting head 44 Groove 16 laser beam 45 Sliding block 17th Cutting nozzle 46 Receiving cylinder 18th workpiece 47 Nozzle insert 19th casing 48 collar 20th Through hole 49 Locking Approach 21 Front side 50 Front side 22nd lid 51 Guide surface 23 Tab 52 Recess 24 screw 53 Guide surface 25th Centering shoulder 54 Leadership area 26th Longitudinal central axis 55 inner thread 27 Face 56 Outer jacket 28 Inlet opening 57 External thread 29 Outlet bore 58 Laser exit opening 30th Deflection mirror 59 Through hole 31 Mirror surface 60 Gas outlet nozzle 32 Focusing mirror 61 Pitch circle 33 Mirror surface 62 Longitudinal axis 63 Chamfer 35 screw 64 cylindrical area 36 gap 65 cone ^ tumble-like end berc 37 Threaded blind hole 66 Gas outlet opening 38 Cooling bore 67 Spike hole

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Reference list 2 -

68 ring groove

69 Supply well

70 groove

71 sealing ring

72 intersection

73 focus

74 cutting gap

75 cutting gas jet

Claims (15)

MEISSKmB-A BÖLTe; 'Patentanwälte' · European Patent Attorney · «<Bremen · Munich * -1- t • S« MfeaHMI »» -! * Ι £ ΜιΙ- £ η * Λ * β * 19ΙΙ0 Erich Bolte · Dipl.-Ing. Dr.EugenPoppDipL-Ing ^ DipL-1 Registration: woifE.sajda-DtpL-Phys. · BIAS research and Dt-am ». Mo »-d *» «Development laboratory for office / officebremen applied beam technology HoUenike73 GmbH D-2800 Bremen 1 Ermlandstrasse 59 Telephone: (042i) 342019 Bremen 71 Telegrams: PATMEIS BREMEN Telex: 246157 meibod Dn-mark Your letter of our mark Date Yonrret Your letter of Our ret Date BIA-14-DE December 23, 1983/9119 Device for cutting workpieces by means of a laser beam 1. Device for cutting workpieces by means of a laser beam, with a high-power _{laser source, in particular a C0 2} laser, which is followed by a cutting head which has cutting optics for focusing the laser beam emerging from the high-power laser source with a focal point outside the cutting head and a cutting nozzle, in which a laser outlet opening for the laser beam and at least one gas outlet nozzle for a cutting gas or the like are arranged,
characterized in that a plurality of gas outlet nozzles (60) with a gas outlet opening (65) which increases in cross section are arranged in the cutting nozzle (17). 15th ■ »4 · -2- 2. Apparatus according to claim 1, characterized in that the gas outlet openings (65) of the gas outlet nozzles (60) evenly distributed concentrically around the fiber outlet opening (58) in the cutting nozzle (17) are. 3. Apparatus according to claim 1 and 2, characterized in that the gas outlet nozzles (60) are inclined with to the longitudinal axis (62) of the laser beam (16) extending longitudinal axis are arranged in the cutting nozzle (17), in such a way that the longitudinal axes of all gas outlet nozzles (60 / in a common, on the longitudinal axis (62) of the laser beam (16) meet the intersection (72) lying. 4. Apparatus according to claim 3 and one or more of the further claims, characterized in that that the intersection (72) of the longitudinal axes of the gas outlet nozzles (60) in the cutting nozzle (17) outside the same at a slight distance from the focal point (73) of the laser beam (16) between the latter and the cutting nozzle (17) or the cutting head (15). 5. Apparatus according to claim 4 and one or more of the further claims, characterized in that that the inclination of the longitudinal axes of the gas outlet nozzles (60) relative to the longitudinal axis (62) of the cutting nozzle (17) or of the laser beam (16) emerging from the same approximately 30 °.
30th 6. Apparatus according to claim 5 and one or more of the further claims, characterized in that that the underside of the cutting nozzle (17) has a conical bevel, at least in the region of the gas outlet openings (65) (63) which is inclined so that the plane the gas outlet openings (65) at right angles '' to the longitudinal ti · · • · a # «Ι · 4 t ι · · ■ « ■. -3- axes of the gas outlet nozzles (60) is directed. 7. The device according to claim 1 and one or more of the further claims, characterized in that the gas outlet nozzles (60) are arranged in the cutting nozzle (17), which are distributed uniformly on a common, concentrically the laser outlet opening (58) surrounding pitch circle (61) are, approximately 120 ° ysets from each other.
IO 8. The device according to claim 1 and one or more of the further claims, characterized in that that all three gas outlet nozzles (60) in the cutting nozzle (17) are designed approximately the same. 9. The device according to claim 1 and one or more of the further claims, characterized in that that the gas outlet nozzles (60) in the cutting nozzle (17) at least in one direction towards the gas outlet openings (65) End regions (65) are designed in the manner of a truncated cone with widening towards the gas outlet openings (65) Diameters. 10. The device according to claim 9 and one or more of the further claims, characterized in that that the gas outlet nozzles (60) are designed as Laval nozzles with an internal, cylindrical area (64), to which the frustoconical end region (65) with its: with a small diameter. I. 11. The device according to claim 10 and one or | several of the other claims, characterized in that | that the gas outlet nozzles designed as Laval nozzles (60) in the cutting nozzle (17) an approximately 5 mm long f cylindrical area (64) with a diameter of approximately 0.7 mm and a frustoconical end region adjoining it -4- (65) also about 5 mm long with a to the cylindrical (middle 1-) part adjoining, smaller Diameter of about 0.7 mm and one die Gas outlet opening (65) forming large diameter of approximately 1.0 mm. 12. The device according to claim 1 and one or more of the further claims, characterized in that that the cutting nozzle (17) consists of a receiving cylinder (46) and a cylindrical one detachably arranged therein There is a nozzle insert (47) with the gas outlet nozzles (60). 13. The device according to claim 12 and one or more of the further claims, characterized in that that the receiving cylinder (46) has a circumferential annular groove (68) in the inner jacket, which with at least one supply bore (69) can be fed with cutting gas, protective gas or the like. 14. The device according to claim 13 and one or more of the further claims, characterized in that that each gas outlet nozzle (60) in the nozzle insert (47) of the cutting nozzle (17) through at least one Feed bore (67) is connected to the annular groove (68) for the common feed of all gas outlet nozzles (60) through the annular groove (68). 15. Device according to: claim 14 and one or several of the further claims, characterized in that each gas outlet nozzle (60) has a feed bore (67) is assigned. 16. The device according to claim 14 and one or more of the further claims, characterized in that that the feed bores (67) starting from -5- ^{1 of} the annular groove (68) in the nozzle insert (47) open in the end of the cylindrical region (64) thereof facing away from the frustoconical end region (65) of the gas outlet nozzles (60).
5 17. The device according to claim 16 and one or more of the further claims »characterized in that that the feed bores (67) have a multiple of the diameter of the cylindrical area (64) of the gas outlet IO step nozzles (60) have a larger diameter, preferably about 3.0 mm. 15 Meissner & Bolte Patent attorneys