Nozzle for a plasma arc torch head, laser cutting head and plasma laser cutting head, assemblies, plasma arc torch head and plasma arc torch comprising same, laser cutting head comprising same, and plasma laser cutting head comprising same

Abstract

Nozzle for a plasma torch head, laser cutting head or plasma laser cutting head, arrangement composed of such a nozzle and of a nozzle protection cap, arrangement composed of such a nozzle and of an electrode, plasma torch head, laser cutting head or plasma laser cutting head having such a nozzle and/or having such an arrangement, plasma torch comprising such a plasma torch head, laser cutting head comprising such a nozzle and/or such an arrangement, plasma laser cutting head comprising such a nozzle and/or such an arrangement, method for plasma cutting, method for laser cutting and method for plasma laser cutting using the same.

Claims

1. A nozzle for a plasma torch head, laser cutting head or plasma laser cutting head, comprising: a body with a longitudinal axis M, a front end, a rear end and a nozzle opening at said front end, wherein said nozzle opening at said front end, as viewed from said front end, comprises at least the following portions in a longitudinal sectional view: a first portion A1 which extends along said longitudinal axis M and which narrows in the direction of said rear end and which has an inner surface and a body edge at said front end, a second portion A3 which extends along said longitudinal axis M and which has an inner surface and a body edge at the transition from said first portion A1 to said second portion A3; and at the transition from said first portion A1 to said second portion A3, the diameter D3 of said second portion A3 is between 0.2 mm and 0.6 mm smaller than the diameter D2 and/or the smallest diameter D2 of said first portion A1; wherein a virtual connecting line V1 between said body edge of said nozzle opening at said front end and said body edge at the transition from said first portion A1 to said second portion A3 and said longitudinal axis M enclose an angle 1 in a range from 15 to 40, and/or the inner surface of the first portion A1 and the longitudinal axis M enclose an angle in a range from 10 to 30 and/or the inner surface of said first portion A1 and said longitudinal axis M enclose an angle 1 in a range from 10 to 30; and either a virtual connecting line V3 between said body edge at the transition from said first portion A1 to said second portion A3 and said body edge at the transition from said second portion A3 to a third portion A5 and said longitudinal axis M encloses an angle 1 in a range from 0 to 8, and widens in the direction of said rear end, or in a range from 172 to 180, and narrows in the direction of said rear end, or runs parallel to the longitudinal axis M; or the inner surface of said second portion A3 widens at an angle in a range from 0 to 8 in the direction of said rear end or narrows at an angle in a range from 172 to 180 in the direction of said rear end, or runs parallel to the longitudinal axis M.

2. The nozzle of claim 1, further comprising, at the transition or before or immediately before the transition from said first portion A1 to said second portion A3, there is situated at least one further inner surface which extends at an angle with respect to said longitudinal axis M in a range from 45 to 120.

3. The nozzle of claim 1 further comprising, as viewed from said front end, after said second portion A3, said third portion A5 extends along said longitudinal axis M, which widens in the direction of said rear end and which has an inner surface.

4. The nozzle of claim 3 wherein said inner surface of said third portion A5 has at least one region which widens along said longitudinal axis M in the direction of said rear end and whose inner surface and said longitudinal axis M enclose an angle in a range from 30 to 90.

5. The nozzle of claim 3 further comprising, as viewed from said front end, a fourth portion A7 with an inner surface is provided after said third portion A5, and a virtual connecting line V4 between said body edge at said transition from said second portion A3 to said third portion A5 and said body inner edge at the transition from said third portion A5 to said fourth portion A7 and said longitudinal axis M enclose an angle 1 in a range from 30 to 90 and/or said inner surface of said third portion A5 and said longitudinal axis M enclose an angle in a range from 30 to 90.

6. The nozzle of claim 3 further comprising, as viewed from said front end, a fourth portion A7 with an inner surface is provided after said third portion A5; wherein the inner surface of said fourth portion A7 has at least one region which widens at an angle with respect to said longitudinal axis M in a range from 0 to 10 in the direction of said rear end or narrows at an angle in a range from 170 to 180 in the direction of said rear end, or runs parallel to said longitudinal axis M; or wherein the inner surface of said fourth portion A7 widens at an angle c with respect to said longitudinal axis M in a range from 0 to 10 in the direction of said rear end or narrows at an angle in a range from 170 to 180 in the direction of said rear end, or runs parallel to said longitudinal axis M.

7. The nozzle of claim 1 further comprising said first portion A1, as viewed from said front end, narrows in any one of conical fashion, convex fashion, concave fashion, continuous fashion, discontinuous fashion, or stepped fashion.

8. The nozzle of claim 1 further comprising said second portion A3 narrows or widens in any one of conical fashion, convex fashion, concave fashion, continuous fashion, discontinuous fashion, stepped fashion, or perpendicularly with respect to the longitudinal axis M.

9. The nozzle of claim 1 further comprising said third portion A5 widens in any one of conical fashion, convex fashion, concave fashion, continuous fashion, discontinuous fashion, stepped fashion, or perpendicularly with respect to the longitudinal axis M.

10. The nozzle of claim 5 further comprising said fourth portion A7 narrows or widens in any one of conical fashion, convex fashion, concave fashion, continuous fashion, discontinuous fashion, stepped fashion, or perpendicularly with respect to the longitudinal axis M.

11. The nozzle of claim 1 further comprising said first portion A1 and said second portion A3 directly follow one another.

12. The nozzle of claim 1 further comprising said second portion A3 and said third portion A5 directly follow one another.

13. The nozzle of claim 5 further comprising said third portion A5 and said fourth portion A7 directly follow one another.

14. The nozzle of claim 1 further comprising said first portion A1, said second portion A3, and said third portion A5 directly follow one another.

15. The nozzle of claim 5 further comprising said second portion A3, said third portion A5, and said fourth portion A7 directly follow one another.

16. The nozzle of claim 5 further comprising said first portion A1, said second portion A3, said third portion A5, and said fourth portion A7 directly follow one another.

17. The nozzle of claim 1 further comprising a largest cross-sectional area A10 of said first portion A1, and/or a largest cross-sectional area A10 of said nozzle opening situated directly at said front end of said nozzle opening, are in the range of 1.7 to 4.0 times larger, than a smallest cross-sectional area A30, A31 of said second portion A3 and/or a smallest cross-sectional area A30, A31 of said nozzle opening.

18. The nozzle of claim 1 further comprising a largest diameter D1 of said first portion A1, and/or a largest diameter D1 of said nozzle opening situated directly at said front end of said nozzle opening, are in the range of 1.3 to 2.1 times larger, than a smallest diameter D3 of said second portion A3 and/or a smallest diameter D3 of said nozzle opening.

19. The nozzle of claim 1 further comprising a largest diameter D1 of said first portion A1, and/or a largest diameter D1 of said nozzle opening situated directly at said front end of said nozzle opening, are in the range of 0.5 mm to 1.2 mm larger than a smallest diameter D3 of said second portion A3 and/or a smallest diameter D3 of said nozzle opening.

20. The nozzle of claim 1 further comprising the quotient L1/L3 of a length L1, extending along said longitudinal axis M, of said first portion A1 and of a length L3, extending along said longitudinal axis M, of said second portion A3 is between 0.5 to 1.2.

21. The nozzle of claim 1 further comprising the quotient L5/L1 of a length L5, extending along said longitudinal axis M, of said third portion A3 and of a length L1, extending along said longitudinal axis M, of said first portion A1 is less than or equal to 1.5.

22. The nozzle of claim 1 further comprising the quotient L5/L3 of a length L5, extending along said longitudinal axis M, of said third portion A3 and of a length L3, extending along said longitudinal axis, of said second portion A3 is less than or equal to 1.25.

23. The nozzle of claim 1 further comprising for the lengths of said first portion A1, said second portion A3, said third portion A5, the following applies: L1<=2 mm, L3<=3 mm, and L5<=2 mm.

24. The nozzle of claim 1 further comprising for the lengths of said fourth portion A7, L7<=3 mm.

25. The nozzle of claim 1 further comprising the quotient L3/D3 of the length L3, extending along said longitudinal axis M, of said second portion A3 and of the diameter D3 of said second portion A3 is between 0.6 and 1.7.

26. The nozzle of claim 5 further comprising a largest diameter D7 of said fourth portion A7 is at least equal to, and at most twice as large as, the largest diameter D1 of said first portion A1 and/or a or the largest diameter D1 of said nozzle opening situated directly at said front end of said nozzle opening.

27. The nozzle of claim 1 further comprising a volume V10 formed by the inner surface(s) of said first portion A1 is 1.3 to 2.2 times larger than a volume V30 formed by the inner surface of said second portion A3.

Description

(1) Further features and advantages of the invention will emerge from the appended claims and from the following description of exemplary embodiments on the basis of the schematic drawings. In the figures:

(2) FIG. 1 shows a sectional view and a sectional detail view (top) of the front end of a nozzle according to a particular embodiment of the invention;

(3) FIG. 2 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (angle =120);

(4) FIG. 3 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (angle =60;

(5) FIG. 4 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A1 narrowing in concave fashion, 1=32);

(6) FIG. 5 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A1 narrowing in convex fashion, 1=32);

(7) FIG. 5.1 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A1 narrowing in convex fashion, 1=32);

(8) FIG. 6 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A1 narrowing in stepped fashion, 1=32);

(9) FIG. 7 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A3 widening in conical fashion, =5);

(10) FIG. 7.1 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A3 widening in concave fashion, 1=5);

(11) FIG. 7.2 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A3 widening in convex fashion, 1=5);

(12) FIG. 8 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A3 narrowing in conical fashion, =175);

(13) FIG. 8.1 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A3 narrowing in convex fashion, 1=175);

(14) FIG. 8.2 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A3 narrowing in concave fashion, 1=175);

(15) FIG. 9 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A5 widening in conical fashion, =80);

(16) FIG. 9.1 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A5 widening in concave fashion, 1=45);

(17) FIG. 9.2 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A5 widening in convex fashion, 1=45);

(18) FIG. 9.3 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A5 widening in concave fashion, 1=45);

(19) FIG. 10 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A7 widening in conical fashion, =175);

(20) FIG. 11 shows a sectional detail view of the front end of a nozzle according to a particular embodiment of the invention (portion A7 narrowing in conical fashion, =175);

(21) FIG. 12 shows, by way of example, a sectional detail view and an enlarged sectional detail view (bottom) of the front end of a nozzle according to a particular embodiment of the invention for the purposes of illustrating the areas A10 and A20;

(22) FIG. 13 and FIG. 13a show, by way of example, two enlarged sectional detail views of the front end of a nozzle according to a particular embodiment of the invention for the purposes of illustrating the areas A30 and A31;

(23) FIG. 14 shows, by way of example, an enlarged sectional detail view of the front end of a nozzle according to a particular embodiment of the invention for the purposes of illustrating the volume V10;

(24) FIG. 15 shows, by way of example, an enlarged sectional detail view of the front end 22 of the for the purposes of illustrating the volume V30;

(25) FIG. 16 is a sectional illustration of a plasma torch head according to a particular embodiment of the invention;

(26) FIG. 17 is a sectional illustration of an arrangement composed of a nozzle, of a nozzle cap, of a nozzle protection cap and of a gas-conducting unit according to a particular embodiment of the invention;

(27) FIG. 17a shows an enlarged detail view of the arrangement composed of a nozzle and of a nozzle protection cap for the purposes of illustrating the projected circular area A70;

(28) FIG. 18 is a sectional illustration of an arrangement composed of a nozzle, of a nozzle protection cap and of a gas-conducting unit according to a particular embodiment of the invention;

(29) FIG. 18a shows an enlarged detail view of the arrangement composed of a nozzle and of a nozzle protection cap for the purposes of illustrating the projected circular area A80;

(30) FIG. 20 shows, by way of example, a gas-conducting unit for secondary gas;

(31) FIG. 19 is a sectional illustration of an arrangement composed of a nozzle, of an electrode and of a gas-conducting unit according to a particular embodiment of the invention;

(32) FIG. 21 shows, by way of example, a gas-conducting unit for plasma gas.

(33) The nozzle 2 shown in FIG. 1 in a sectional view (top) and in a sectional detail view (bottom) for a plasma arc torch comprises a body 20 with an overall length L20, which extends along a longitudinal axis M, with an inner surface 21 and with an outer surface 23, with a front end 22 and with a rear end 28, and with a nozzle opening 24 at the front end 22. Furthermore, the body 20 has, at its front end 22, a groove 238. When the nozzle 2 is installed in the plasma arc torch, a round ring 240 (see FIG. 16) is situated in the groove 238 for the purposes of sealing off the space between nozzle 2 and nozzle cap 5 (see FIG. 16).

(34) The inner surface 21 of the body 20 of the nozzle 2 has, proceeding from the front end 22 (nozzle opening 24), a first portion A1 which extends along the longitudinal axis M and which firstly narrows in conical fashion with an angle between its inner surface 211 and the longitudinal axis M, in this case by way of example approximately 19, over a length L1, for example 1.0 mm, and then has a projection in the direction of the longitudinal axis M, which, between its inner surface 213 and the longitudinal axis M, forms an angle , in this case for example 90. The nozzle opening 24 has, directly at the front end 22, a diameter D1, in this case for example 1.9 mm, and, at the end of the conical region of the inner surface 211 of the first portion A1, a diameter D2, in this case for example 1.2 mm. Owing to the projection, in this case for example 0.1 mm, the diameter of the nozzle opening 24 then decreases to D3, in this case for example 1.0 mm.

(35) This is directly adjoined by the second portion A3 with the diameter D3 and a length L3, for example 1.0 mm, which second portion has a cylindrical inner surface 220. Said portion is adjoined by the third portion A5, the inner surface 224 of which widens conically with an angle between its inner surface 224 and the longitudinal axis M, in this case for example 45, from the diameter D3 to the diameter D7, in this case for example 2.8 mm. Said portion extends along the longitudinal axis M over the length L5, in this case for example 0.9 mm. It is adjoined by the fourth portion A7 with the diameter D7, which has a cylindrical inner surface 227 with a length L7, for example 1.2 mm. This is adjoined by a further region which widens conically.

(36) With D1=1.9 mm and D3=1.0 mm, D1 amounts to 1.9 times the diameter D3. The diameter D1 is 0.9 mm larger than the diameter D3.

(37) The area A10 formed perpendicular to the longitudinal axis M by the diameter D1 of the first portion A1 directly at the front end 22 of the nozzle opening 24, which area is illustrated in FIG. 12, amounts to approximately 2.8 mm.sup.2, determined in accordance with
[A10=3.141/4*D1.sup.2].
The area A30 formed perpendicular to the longitudinal axis M by the smallest diameter D3 of the second portion A3 of the nozzle opening 24, which area is illustrated in FIG. 13, amounts to approximately 0.8 mm.sup.2, determined in accordance with
[A30=3.141/4*D3.sup.2].

(38) The area A10 therefore amounts to approximately 3.6 times the area A30.

(39) The length L1=1.0 mm of the first portion A1 and the length L3=1.0 mm A3 of the second portion result in a ratio of L1/L3=1. The quotient of the length L3 and of the diameter D3 of the second portion A3 likewise amounts to 1. Furthermore, the diameter D1=1.9 mm is smaller than the diameter D7=2.8 mm.

(40) FIG. 1 furthermore shows a virtual connecting line V1 which extends between the body edge 201 of the nozzle opening 24 with the diameter D1 at the front end 22 and the body edge 203 at the transition from the first portion A1 to the second portion A3 of the nozzle opening 24 with the diameter D3. The angle 1 enclosed by the connecting line V1 and the longitudinal axis M amounts to approximately 24.

(41) The volume V10, formed by the inner surfaces 211 and 213, of the nozzle opening 24 of the first portion A1 amounts to approximately 1.9 mm.sup.3, calculated in accordance with
[V10=3.141*L1/3*((D1/2).sup.2+(D1/2*D2/2)+(D2/2).sup.2].

(42) The volume V30, formed by the inner surface 220, of the nozzle opening 24 of the second portion A3 amounts to approximately 0.8 mm.sup.3, calculated in accordance with [V30=3.141*(D3/2).sup.2*L3]. Volume V10 is thus approximately 1.9 times larger than volume V30.

(43) FIG. 2 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. Said nozzle differs from that in FIG. 1 in that the projection in the direction of the longitudinal axis M, which forms an angle =100 between its inner surface 213 and the longitudinal axis M.

(44) FIG. 3 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. Said nozzle differs from that in FIG. 1 in that the projection in the direction of the longitudinal axis M, which forms an angle =60 between its inner surface 213 and the longitudinal axis M.

(45) FIG. 4 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. Said nozzle differs from that in FIG. 1 in that the first portion A1 has, proceeding from the front end, an inner surface 211 which narrows in concave fashion. The virtual connecting line V1 that extends between the body edge 201 of the nozzle opening 24 with the diameter D1 at the front end 22 and the body edge 203 at the transition from the first portion A1 to the second portion A3 of the nozzle opening 24 with the diameter D3 encloses for example an angle 1 of approximately 32 with the longitudinal axis M. The diameter D1 amounts in this case to for example 2.4 mm, the diameter D3=1.4 mm, and thus the diameter D1 amounts to approximately 1.7 times the diameter D3.

(46) The area A10 formed perpendicular to the longitudinal axis M by the diameter D1 of the first portion A1 directly at the front end 22 of the nozzle opening 24, which area is illustrated in FIG. 12, amounts to approximately 4.5 mm.sup.2, determined in accordance with
[A10=3.141/4*D1.sup.2].

(47) The area A30 formed perpendicular to the longitudinal axis M by the smallest diameter D3 of the second portion A3 of the nozzle opening 24, which area is illustrated in FIG. 13, amounts to approximately 1.5 mm.sup.2, determined in accordance with
[A30=3.141/4*D3.sup.2].

(48) The area A10 therefore amounts to approximately 2.9 times the area A30.

(49) The length L1 amounts to for example 0.8 mm, and the length L3 for example to 1.2 mm, and thus the length L1 amounts to 0.67 times the length L3.

(50) The quotient of the length L3=1.2 mm and of the diameter D3=1.4 mm of the second portion A3 amounts to 0.86. Furthermore, the diameter D1=2.4 mm is smaller than the diameter D7=3.0 mm.

(51) The volume V10, formed by the inner surface 211, of the nozzle opening 24 of the first portion A1 amounts to approximately 2.3 mm.sup.3. The volume V30, formed by the inner surface 220, of the nozzle opening 24 of the second portion A3 amounts to approximately 1.8 mm.sup.3. Volume V10 is thus approximately 1.3 times larger than volume V30.

(52) FIG. 5 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 4. Said nozzle differs from that in FIG. 1 in that the first portion A1 has, proceeding from the front end, an inner surface 211 which narrows in convex fashion. The virtual connecting line V1 that extends between the body edge 201 of the nozzle opening 24 with the diameter D1 at the front end 22 and the body edge 203 at the transition from the first portion A1 to the second portion A3 of the nozzle opening 24 with the diameter D3 encloses for example an angle 1 of approximately 32 with the longitudinal axis M. The diameter D1 amounts in this case to for example 2.4 mm, and the diameter D3 to 1.4 mm, and thus the diameter D1 amounts to approximately 1.7 times the diameter D3. The length L1 amounts to for example 0.8 mm, and the length L3 for example to 1.2 mm, and thus the length L1 amounts to approximately 0.67 times the length L3.

(53) The quotient of the length L3=1.2 mm and of the diameter D3=1.4 mm of the second portion A3 amounts to approximately 0.86. Furthermore, the diameter D1=2.4 mm is smaller than the diameter D7=3.0 mm.

(54) The exemplary specifications from FIG. 4 apply to the areas A10 and A30, and the same applies to the specifications of the volumes V10 and V30.

(55) If the body edge 201 is not clearly recognizable as such, for example because the convex inner surface 211 merges in continuous or flowing fashion into the surface 230, then the region of the inner surface(s) with body edge is meant if, as viewed from the rear end 28 of the nozzle 2, an angle 2 of 65 is exceeded between a tangent T applied to the inner surface 211 and the longitudinal axis M. The virtual connecting line V1 then extends between said region and body edge 203. This is shown in FIG. 5.1.

(56) FIG. 6 shows a further exemplary embodiment of a nozzle 2 similar to FIG. 4. Said nozzle differs from that in FIG. 4 in that the first portion A1 has, proceeding from the front end, an inner surface 211 which narrows in stepped fashion. The virtual connecting line V1 that extends between the body edge 201 of the nozzle opening 24 with the diameter D1 at the front end 22 and the body edge 203 at the transition from the first portion A1 to the second portion A3 of the nozzle opening 24 with the diameter D3 encloses for example an angle 1 of approximately 32 with the longitudinal axis M. The diameter D1 amounts in this case to for example 2.4 mm, the diameter D3=1.4 mm, and thus the diameter D1 amounts to 1.7 times the diameter D3. The length L1=0.8 mm of the first portion A1 and the length L3=1.2 mm A3 of the second portion result in a ratio of L1/L3=0.67. The quotient of the length L3 and of the diameter D3 of the second portion A3 amounts to approximately 0.86. The diameter D7 amounts to for example 3.0 mm. Thus, the diameter D1=2.4 mm is smaller than the diameter D7=3.0 mm.

(57) The exemplary specifications from FIG. 4 apply to the areas A10 and A30, and the same applies to the specifications of the volumes V10 and V30.

(58) FIG. 7 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. The dimensions are identical to those from FIG. 1. Only the second portion A3 is designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 220 widens at an angle of for example 5 with respect to the longitudinal axis M. Here, the widening is realized in conical form. The diameter D31 of the portion A3 at the transition to the portion A5 is thus larger than the diameter D3 at the transition from the first portion A1 to the second portion A3 of the nozzle opening 24.

(59) FIG. 7.1 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 7. The dimensions are identical to those from FIG. 7. Only the second portion A3 is designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 220 widens in concave fashion. The virtual connecting line V3 that extends between the body edge 203 at the transition from the first portion A1 to the second portion A3 and the body edge 205 at the transition from the second portion A3 to the third portion A5 encloses for example an angle 1 of approximately 5 with the longitudinal axis M. The diameter D31 of the portion A3 at the transition to the portion A5 is thus, in this example, larger than the diameter D3 at the transition from the first portion A1 to the second portion A3 of the nozzle opening 24.

(60) FIG. 7.2 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 7.1. The dimensions are identical to those from FIG. 7.1. Only the second portion A3 is designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 220 widens in not concave but rather convex fashion.

(61) FIG. 8 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. The second portion A3 is designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 220 narrows at an angle of for example 175 with respect to the longitudinal axis M. Here, the narrowing is realized in conical form. The diameter D32=1.17 mm of the second portion A3 at the transition from the first portion A1 to the second portion A3 is thus larger than the diameter D3=1 mm at the transition from the second portion A3 to the third portion A of the nozzle opening 24. The diameter D2 amounts to 1.4 mm and the diameter D1=2.1 mm. The angle amounts to 19, and the angle 1 amounts to 21.

(62) FIG. 8.1 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 8. The second portion A3 is however designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 220 narrows in convex fashion. The virtual connecting line V3 that extends between the body edge 203 at the transition from the first portion A1 to the second portion A3 and the body edge 205 at the transition from the second portion A3 to the third portion A5 encloses for example an angle 1 of approximately 175 with the longitudinal axis M. The diameter D32=1.17 mm of the second portion A3 at the transition from the first portion A1 to the second portion A3 is thus larger than the diameter D3=1 mm at the transition from the second portion A3 to the third portion A of the nozzle opening 24. The diameter D2 amounts to 1.4 mm and the diameter D1=2.1 mm. The angle in this example amounts to 19, and the angle 1 in this example amounts to 21.

(63) FIG. 8.2 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 8.1. The second portion A3 is however designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 220 narrows in not convex but rather concave fashion.

(64) FIG. 9 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. The dimensions are identical to those from FIG. 1. The third portion A5 has for example an angle of 80 between its inner surface 224 and the longitudinal axis M, and widens. It is however a nozzle whose outer contour differs from the other exemplary embodiments. Said nozzle is for example suitable for use in plasma torches, laser heads or plasma laser heads without liquid cooling for the nozzle. In this example, said nozzle has no groove 238 for receiving a round ring. A corresponding arrangement is shown in FIG. 18.

(65) FIG. 9.1 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 9. The dimensions are identical to those from FIG. 9. Only the third portion A5 is designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 224 widens in concave fashion. The virtual connecting line V4, which extends between the body edge 205 (which in this case can also be referred to as inner corner or body inner edge) at the transition from the second portion A3 to the third portion A5 and the body edge 206 (which in this case can also be referred to as inner corner or body inner edge) at the transition from the third portion A5 to the fourth portion A7, encloses for example an angle 1 of approximately 45 with the longitudinal axis M.

(66) If the body edge 206 is not clearly recognizable as such, for example because the concave inner surface merges in continuous or flowing fashion into the inner surface 227, then the region 206 of the inner surface(s) is meant if, as viewed from the front end 22 of the nozzle, an angle 2 of 20 is undershot between a tangent T applied to the inner surface 224 and the longitudinal axis M. This is shown in FIG. 9.3.

(67) FIG. 9.2 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 9. The dimensions are identical to those from FIG. 9. Only the third portion A5 is designed such that, as viewed from the front end 22 of the nozzle 2, its inner surface 224 widens in convex fashion. The virtual connecting line V4 that extends between the body edge 205 at the transition from the second portion A3 to the third portion A5 and the body edge 206 at the transition from the third portion A5 to the fourth portion A7 encloses for example an angle 1 of approximately 45 with the longitudinal axis M.

(68) If the body edge 206 is not clearly recognizable as such, for example because the concave inner surface 224 merges in continuous or flowing fashion into the surface 227, then the region of the inner surface(s) with body edge 206 is meant if, as viewed from the front end 22 of the nozzle 2, an angle 2 of 20 is undershot between a tangent T applied to the inner surface 224 and the longitudinal axis M. The virtual connecting line V4 then extends between said region 206 and body edge 205. This is shown in FIG. 9.3, which shows a concavely widening third portion A5.

(69) FIG. 10 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. The dimensions are identical to those from FIG. 1. The fourth portion A7 has for example an angle of 5 between its inner surface 227 and the longitudinal axis M, and widens.

(70) FIG. 11 shows the detail view of a further exemplary embodiment of a nozzle 2 similar to FIG. 1. The dimensions are identical to those from FIG. 1. The fourth portion A7 has for example an angle of 175 between its inner surface 227 and the longitudinal axis M, and narrows.

(71) Radii, for example of the magnitude of 0.1 mm, may be arranged at the transitions between the respective portions A1, A3, A4, A5 and A7.

(72) FIG. 12, FIG. 13 and FIG. 13a show the areas A10, A20, A30 and A31, formed perpendicular to the longitudinal axis M by the diameters D1, D2 and D3, of the nozzle opening 24. In the exemplary embodiments in FIGS. 1 to 11, the area A10 is at least 1.7 times larger, advantageously at least 2.1 times larger, than the area A30. Furthermore, it is at most 4 larger, advantageously at most 3.7 times larger, than the area A30.

(73) FIG. 14 shows the volume V10, enclosed by the inner surfaces 211 and 213, of the nozzle opening 24 of the first portion A1 and FIG. 15 shows the volume V30 of the nozzle opening 24 of the second portion A3 enclosed by the inner surface 220. In the exemplary embodiments, the volume V10 is larger, advantageously at least 1.3 times larger, and/or at most 2.5 times larger, advantageously at most 2.2 times larger, than the volume V30.

(74) FIG. 16 shows the sectional image of a plasma torch head 1, which may be a constituent part of a plasma torch.

(75) The plasma torch head 1 has a torch body 8, an electrode 3, a nozzle 2 according to the invention, a nozzle cap 5, a nozzle bracket 81 which receives the nozzle 2, and a nozzle protection cap 6 which fixes the nozzle 2 in the nozzle bracket 81.

(76) In this figure, the nozzle 2 from FIG. 1 is used as an example.

(77) The front end 33 of the electrode 3 projects into the interior space of the nozzle 2. Furthermore, a gas-conducting unit 4 for the plasma gas or process gas PG is situated between the electrode 3 and the nozzle 2. The gas-conducting unit 4 has openings 41 which conduct the plasma gas or process gas through and in this case for example lead radially into the interior space between the electrode 3 and the nozzle 2. The plasma gas or process gas PG can be set in rotation by means of an offset with respect to the radial. The gas-conducting unit 4 electrically isolates the electrode 3 and nozzle 2 from one another. The electrode 3 may be liquid-cooled in the interior; this is not illustrated here. The cooling medium (WVfeed line, WRreturn line) flows in the space 51 between the nozzle 2 and the nozzle cap 5 and cools these.

(78) The front end of the nozzle 22 is at least partially covered by the nozzle protection cap 6. The nozzle protection cap 6 has an opening 64 which is in alignment with the nozzle opening 24 on the longitudinal axis M. A gas-conducting unit 7 for the secondary gas SG is situated between the nozzle cap 5, the front end 22 of the nozzle 2 and the nozzle protection cap 6. The gas-conducting unit 7 has openings 71 which conduct the secondary gas SG through and in this case for example lead radially into the interior space 61 between the nozzle cap 5, the front end 22 of the nozzle 2 and the nozzle protection cap 6. The plasma gas or process gas PG can be set in rotation by means of an offset with respect to the radial. The gas-conducting unit 7 electrically isolates the nozzle cap 5 and the nozzle protection cap 6 from one another.

(79) During the plasma cutting, the plasma gas or process gas PG is ionized by an arc and ultimately flows out of the nozzle opening 24 and the opening of the nozzle protection cap 64.

(80) FIG. 17 and FIG. 17a each show a sectional detail view of an arrangement according to a particular embodiment of the invention, which is a constituent part of the plasma torch head from FIG. 16. This arrangement may however likewise be a constituent part of a laser cutting head or be a plasma laser cutting head. The claimed arrangement comprises the nozzle 2 and the nozzle protection cap 6. The nozzle cap 5 and the gas-conducting unit 7 are also shown.

(81) The front end of the nozzle 2 is at least partially covered by the nozzle protection cap 6. The nozzle protection cap 6 has an opening 64 which is in alignment with the nozzle opening 24 on the longitudinal axis M. A gas-conducting unit 7 for secondary gas SG is situated between the nozzle cap 5, the front end 22 of the nozzle 2 and the nozzle protection cap 6. The gas-conducting unit 7 has openings 71 which conduct the secondary gas SG through and in this case for example lead radially into the interior space 61 between the nozzle cap 5, the front end 22 of the nozzle 2 and the nozzle protection cap 6. The plasma gas or process gas PG can be set in rotation by means of an offset with respect to the radial. The gas-conducting unit 7 electrically isolates the nozzle cap 5 and the nozzle protection cap 6 from one another.

(82) The nozzle 2 has, for example as per FIG. 1, a diameter D1=1.9 mm and D3=1.0 mm. The nozzle protection cap 6 has an opening 64 with a smallest diameter D6 of 3.0 mm. The diameter D6 is larger than the diameters D1 and D3. The area A60 formed perpendicularly with respect to the longitudinal axis by the diameter D6 is larger than the area A10 formed by the diameter D1 and the area A30 formed by the diameter D3.

(83) The angle of the nozzle 2 amounts to 19 in this example and the angle 1 of the nozzle 2 amounts to 24 in this example. If one virtually extends the inner surfaces 211, which narrow conically as viewed from the front, in the direction of the front end 22 of the nozzle, that is to say out of the nozzle 2, then this forms the virtual line V2. Said virtual line does not intersect the body edge 65, formed by the opening 64 with the diameter D6, of the nozzle protection cap 6. The same applies to the extended virtual connecting line V1 between the body edge 201 of the nozzle opening 24 at the front end 22 and the body edge 203 at the transition from the first portion A1 to the second portion A3.

(84) The area A60 and the diameter D6 of the opening 64 of the nozzle protection cap 6 are larger than the virtual areas A70 and A80 or diameters of the nozzle 2 projected by the extended virtual connecting lines V1 and V2 onto the nozzle protection cap 6.

(85) Furthermore, the length L61 of the shortest spacing between the outer surface of the front end 22 of the nozzle 2 and the inner surface of the nozzle protection cap 6 is for example 0.7 mm and is therefore smaller than the length L1=1.0 mm of the first portion A1 and the length L3=1.0 mm of the second portion A3 of the nozzle 2 and also smaller than the sum L1 and L3, which amounts to 2 mm.

(86) FIG. 18 and FIG. 18a show a sectional detail view of an arrangement according to a particular embodiment of the invention. The claimed arrangement comprising the nozzle 2 from FIG. 9 and a nozzle protection cap 6. A gas-conducting unit 7 is also shown. This arrangement may be a constituent part of a plasma torch head, of a laser cutting head or may be a plasma laser cutting head.

(87) By contrast to FIG. 17, the nozzle 2 is not surrounded by a nozzle cap. The nozzle 2 has a diameter D1=1.9 mm and D3=1.0 mm. The nozzle protection cap 6 has an opening 64 with a smallest diameter D6 of 3.0 mm. The diameter D6 is larger than the diameter D1 and D3 of the nozzle 2. The area A60 formed perpendicularly with respect to the longitudinal axis by the diameter D6 is larger than the area A10 formed by the diameter D1 and the area A30 formed by the diameter D3.

(88) The front end of the nozzle 22 is at least partially covered by the nozzle protection cap 6. The nozzle protection cap 6 has an opening 64 which is in alignment with the nozzle opening 24 on the longitudinal axis M. A gas-conducting unit 7 for the secondary gas SG is situated between the nozzle 2 and the nozzle protection cap 6. The gas-conducting unit 7 has openings 71 which conduct the secondary gas SG through and in this case for example leads radially into the interior space 61 between the nozzle 2 and the nozzle protection cap 6. The plasma gas PG can be set in rotation by means of an offset with respect to the radial (see FIG. 21). The gas-conducting unit 7 electrically isolates the nozzle 2 and the nozzle protection cap 6 from one another.

(89) The angle of the nozzle 2 amounts to 19 in this example and the angle 1 of the nozzle 2 amounts to 24 in this example. If one virtually extends the inner surface, which narrows conically as viewed from the front, in the direction of the front end 22 of the nozzle 2, that is to say out of the nozzle 2, then this forms the virtual line V2. Said virtual line does not intersect the body edges 65, formed by the opening 64 with the diameter D6, of the nozzle protection cap 6. The same applies to the extended virtual connecting line V1 between the body edge 201 of the nozzle opening 24 at the front end 22 and the body edge 203 at the transition from the first portion A1 to the second portion A3.

(90) The area A60 and the diameter D6 of the opening 64 of the nozzle protection cap 6 are larger than the virtual areas A70 and A80 or diameters of the nozzle 2 projected by the extended virtual connecting lines V1 and V2 onto the nozzle protection cap 6.

(91) Furthermore, the length L61 of the shortest spacing between the outer surface of the front end 22 of the nozzle 2 and the inner surface of the nozzle protection cap 6 is for example 0.7 mm and is therefore smaller than the length L1=1.0 mm of the first portion A1 and the length L3=1.0 mm of the second portion A3 of the nozzle 2 and also smaller than the sum L1 and L3, which amounts to 2 mm.

(92) FIG. 19 shows a sectional detail view of an arrangement according to a particular embodiment of the invention, which is a constituent part of the plasma torch head from FIG. 16. The claimed arrangement comprises a nozzle 2 according to a particular embodiment of the invention and an electrode 3. A gas-conducting unit 4 is also shown.

(93) The front end 33 of the electrode 3 projects into the interior space of the nozzle 2. Furthermore, a gas-conducting unit 4 for the plasma gas PG is situated between the electrode 3 and the nozzle 2. The gas-conducting unit 4 has openings 41 which conduct the plasma gas through and in this case for example lead radially into the interior space between the electrode 3 and the nozzle 2. The plasma gas PG can be set in rotation by means of an offset with respect to the radial. The gas-conducting unit 4 electrically isolates the electrode 3 and the nozzle 2 from one another. The spacing L13 between the front end 33 of the electrode 3 and the transition from the third portion A5 to the second portion A3 of the nozzle opening 24 of the nozzle 2 is 6 mm in length, the length L1 of the first portion A1 and the length L3 of the second portion A3 each amount to 1 mm. The sum of the lengths L1 and L3 then amounts to 2 mm. Thus, both L1, L2 and the sum of both are shorter than the length of the spacing L13.

(94) FIG. 20 shows, by way of example, the gas-conducting unit 7 for the secondary gas SG. It can be seen from the central sectional illustration that the openings 71 are arranged so as to be offset with respect to the radial to the longitudinal axis M. The gas flowing through the openings 71 is thus set in rotation. The rotation may however also be realized by means of a different spatial orientation of the openings, for example an inclination with respect to the longitudinal axis M.

(95) FIG. 21 shows, by way of example, the gas-conducting unit 4 for the plasma gas or process gas. It can be seen from the central sectional illustration that the openings 41 are arranged so as to be offset with respect to the radial to the longitudinal axis M. The gas flowing through the openings 41 is thus set in rotation. The rotation may however also be realized by means of a different spatial orientation of the openings, for example an inclination with respect to the longitudinal axis M.

(96) The above description has been directed to a nozzle for plasma cutting or for a plasma torch head. The plasma torch head may be a plasma torch cutting head. The description is however intended to also apply analogously to a nozzle for laser cutting or for a laser cutting head and for plasma laser cutting or for a plasma laser cutting head.

(97) The features of the invention disclosed in the above description, in the drawings and in the claims may be essential both individually and in any combinations for the realization of the invention in its various embodiments.

LIST OF REFERENCE DESIGNATIONS

(98) 1 Plasma torch, plasma torch head, plasma torch cutting head, plasma laser cutting head 2 Nozzle 3 Electrode 4 Gas-conducting unit for plasma gas; process gas 5 Nozzle cap 6 Nozzle protection cap 7 Gas-conducting unit for secondary gas 8 Torch body 20 Body 21 Inner surface 22 Front end 23 Outer surface 24 Nozzle opening 25 Interior space of the nozzle 28 Rear end 31 Emission insert of the electrode 3 32 Electrode holder 33 Front end of the electrode 34 Outer surface of the electrode 41 Openings in the gas-conducting unit 4 for the plasma gas 51 Space between nozzle 2 and nozzle cap 5 55 Nozzle protection cap bracket 61 Interior space between nozzle protection cap 6 and nozzle cap 5 and nozzle 2 62 Inner surface of the nozzle protection cap 64 Opening of the nozzle protection cap 65 Body edge of the opening of the nozzle protection cap 71 Openings in the gas-conducting unit 7 for the secondary gas 81 Nozzle holder 201 Body edge of the nozzle opening at the front end 22 of the nozzle opening 24 203 Body edge of the nozzle opening at the front end 22 of the nozzle opening 24 at the transition of the portion A1 to A3 204 Body edge between inner surfaces 211 and 213 205 Body edge between inner surfaces 220 and 224 206 Body edge between inner surfaces 224 and 227 211 Inner surface of the first portion A1 213 Further inner surface of the first portion A1 220 Inner surface of the second portion A3 224 Inner surface of the third portion A5 227 Inner surface of the fourth portion A7 230 Surface at the front end 22 of the nozzle 238 Groove 240 Round ring A1 First portion A3 Second portion A5 Third portion A7 Fourth portion A10 Area of the nozzle opening at the front end 22 at D1 A20 Further area of the nozzle opening in the first portion at D2 A30 Area of the smallest nozzle opening in the second portion A3 at D3 A31 Area of the nozzle opening in the second portion A60 Area of the opening 64 of the nozzle protection cap A70 Projected virtual area from the connecting line V1 onto the plane of the area A60 A80 Projected virtual area from the connecting line V2 onto the plane of the area A60 D1 Diameter of the nozzle opening in the first portion A1 at the front end D2 Further diameter of the nozzle opening in the first portion A1 D3 Diameter of the nozzle opening in the second portion (=0 or 180) D31 Further diameter of the nozzle opening in the second portion (>0 to 8) D32 Further diameter of the nozzle opening in the second portion (<180 to 172) D6 Diameter of the opening 64 of the nozzle protection cap D7 Diameter in the portion A7 D70 Diameter of the projected virtual area A70 D80 Diameter of the projected virtual area A80 L1 Length of the first portion A1 L3 Length of the second portion A3 L5 Length of the third portion A5 L7 Length of the fourth portion A7 L13 Spacing between the front end 33 of the electrode 3 L61 Spacing between the outer surface of the front end 22 of the nozzle 2 and the inner surface 62 of the nozzle protection cap 6 L20 Total length of the nozzle M Longitudinal axis PG Plasma gas or process gas SG Secondary gas T Tangent V1 Virtual connecting line between the body edge 201 and 203 V2 Virtual connecting line between the body edge 201 and 204 V3 Virtual connecting line between the body edge 203 and 205 V4 Virtual connecting line between the body edge 205 and 206 V10 Volume of the first portion A1 of the nozzle opening 24 V30 Volume of the second portion A3 of the nozzle opening 24 WR Coolant return line WV Coolant feed line Angle between longitudinal axis M and the virtual connecting line V2 or the inner surface 211 of the first portion A1 1 Angle between the longitudinal axis M and the virtual connecting line V1 of the first portion A1 2 Angle between the longitudinal axis M and the tangent T Angle between longitudinal axis M and inner surface 213 of the first portion A1 Angle between longitudinal axis M and inner surface 220 of the second portion A3 1 Angle between longitudinal axis M and the virtual connecting line V3 of the second portion A3 Angle between longitudinal axis M and inner surface 224 of the third portion A5 1 Angle between longitudinal axis M and the virtual connecting line V4 of the third portion A5 Angle between longitudinal axis M and inner surface 227 of the fourth portion A7