LASER MACHINING TOOL

Abstract

The invention relates to a laser machining tool (100), in particular a laser cutting tool, comprising a machining device (1) which is guided on a bridge (10) and has a movable carriage (2), on which a machining unit (3) is arranged, which has a machining head (4), which is designed in such a way that it directs a laser beam of laser light onto a workpiece to be machined, wherein a flexible fibre cable (6) for supplying the laser light from a laser light source (16) is connected to the machining head (4) and the machining unit (3) can be moved linearly together with the machining head (4) relative to the movable carriage (2). The fibre cable (6) is fixed to the machining unit (3) with a first fixing means (7) and fixed to the movable carriage (2) with a second fixing means (8), wherein the fibre cable (6) is freely movable for enabling a linear movement of the machining unit (3) relative to the movable carriage (2) in a predetermined guide plane (G) between the first and second fixing means (7, 8).

Claims

1-14. (canceled)

15. A laser machining tool comprising: a machining device which is guided on a bridge and has a movable carriage, on which a machining unit is arranged, wherein the machining device includes a machining head, which is configured to direct a laser beam of laser light onto a workpiece to be machined, wherein a flexible fibre cable for supplying the laser light from a laser light source is connected to the machining head and the machining unit can be moved linearly together with the machining head relative to the movable carriage, wherein the fibre cable is fixed to the machining unit with a first fixing means and fixed to the movable carriage with a second fixing means, wherein the fibre cable is freely movable for enabling a linear movement of the machining unit relative to the movable carriage in a predetermined guide plane between the first and second fixing means, and wherein guide means defining the predetermined guide plane are provided in order to restrict movement of the fibre cable in a direction running perpendicular to the predetermined guide plane, the guide means comprising at least two parallel stop elements for the fibre cable.

16. The laser machining tool according to claim 15, wherein the fibre cable is guided in the predetermined guide plane with a maximum deflection of 179° between the first and second fixing means.

17. The laser machining tool according to claim 16, wherein the fibre cable is guided in the predetermined guide plane with a maximum deflection of 120°, between the first and second fixing means.

18. The laser machining tool according to claim 15, wherein only the fibre cable is fixed with the first and second fixing means.

19. The laser machining tool according to claim 15, wherein, in the operating position of the laser machining tool, the fibre cable runs substantially in the vertical direction at the location of the first fixing means and/or runs substantially in the horizontal direction at the location of the second fixing means.

20. The laser machining tool according to claim 15, wherein the predetermined guide plane extends perpendicular to the bridge.

21. The laser machining tool according to claim 15, wherein at least one stop element is formed by a wall section and/or at least one stop element is formed by one or a plurality of rods and/or wires.

22. The laser machining tool according to claim 15, wherein the first fixing means and/or the second fixing means each have a clamping device for clamping the fibre cable.

23. The laser machining tool according to claim 15, wherein an energy chain is provided between the movable carriage and the machining unit, wherein, in the energy chain, lines other than the fibre cable are guided from the movable carriage to the machining unit.

24. The laser machining tool according to claim 15, wherein the carriage is movably guided on the bridge, wherein the bridge can be moved perpendicular to the carriage.

25. A machining device for a laser machining tool, wherein the machining device is configured for guiding on a bridge and contains a movable carriage, on which a machining unit is arranged, wherein the machining unit includes a machining head that is configured such that, when using the machining device in the laser machining tool, the machining unit directs a laser beam of laser light onto a workpiece to be machined, wherein a flexible fibre cable for supplying the laser light from a laser light source is connected to the machining head and the machining unit can be moved linearly together with the machining head relative to the movable carriage, wherein the fibre cable is fixed to the machining unit with a first fixing means and fixed to the movable carriage with a second fixing means, wherein the fibre cable is freely movable for enabling a linear movement of the machining unit relative to the movable carriage in a predetermined guide plane between the first and second fixing means, and wherein guide means defining the predetermined guide plane are provided in order to restrict movement of the fibre cable in a direction running perpendicular to the predetermined guide plane, the guide means comprising at least two parallel stop elements for the fibre cable.

26. The machining device according to claim 25, wherein the machining device is configured to work as a machining device for a laser machining tool according to claim 16.

27. The laser machining tool according to claim 16, wherein the fibre cable is guided in the predetermined guide plane with a maximum deflection 100°, between the first and second fixing means.

Description

[0028] In the figures:

[0029] FIG. 1 shows a schematic perspective illustration of a machining device which is installed in an embodiment of the laser machining tool according to the invention, wherein the machining head is in a first vertical position;

[0030] FIG. 2 shows an illustration analogous to FIG. 1, wherein the machining head is in a second vertical position which is lower than the first vertical position from FIG. 1; and

[0031] FIG. 3 shows a schematic perspective overall view of the laser machining tool in which the machining device from FIGS. 1 and 2 is installed.

[0032] A variant of the invention is described below using a laser machining tool 100 in the form of a laser cutting tool, the overall structure of which can be seen in FIG. 3. The laser machining tool is used to cut metal sheets using a machining device via which a high-energy laser beam is directed onto the metal sheets.

[0033] FIG. 1 shows in detail the machining device, which is designated as a whole by the reference symbol 1. This device comprises a movable carriage 2 which, in the embodiment described here, is designed as a cross or cutting carriage and supports a machining unit 3. Corresponding to the Cartesian coordinate system shown in FIG. 1, the machining unit 3 can be moved in the vertical z-direction relative to the carriage 2 by means of an actuator system (not shown), as will be explained further below. The carriage 2 is arranged on a bridge 10 which, in the embodiment described here, represents a cutting bridge and only a partial section of which is shown in the view of FIG. 1. The carriage 2 can be moved along this bridge by means of an actuator system (not shown) in the horizontal y-direction according to the coordinate system shown.

[0034] As can be seen from the overall view of the laser machining tool according to FIG. 3, the bridge 10 can also be moved, specifically in the horizontal x-direction of the coordinate system shown, i.e. perpendicular to the path of the carriage 2. For this purpose, the bridge is arranged on a frame 14 with two supports 15 and 15′ extending in the y-direction. The bridge lies on these supports and can be moved along their longitudinal direction using suitable actuators (not shown).

[0035] According to FIG. 1, the machining unit 3 comprises a machining head 4 which, in the embodiment described here, is designed as a cutting head and to which a fibre cable 6 is connected, via which laser light is supplied to the machining head. The laser light originates from a laser light source which is designated by reference symbol 16 in FIG. 3. In the machining head 4, there is an optical system which generates a laser beam from the laser light which is guided into the machining head 4 via the fibre cable 6 and which is directed downwards. The sheet metal to be cut (not shown), which is positioned between the supports 15 and 15′ of the frame 14 according to the illustration in FIG. 3, is located below the machining head during operation of the laser machining tool.

[0036] In addition to the fibre cable 6, the machining head 4 is supplied in a manner known per se with further lines that are required for its operation. These lines, which are not shown for reasons of clarity, include, inter alia, electrical lines for power supply, control cables and hoses for supplying compressed air and the gas required for the cutting process. The lines are guided separately to the fibre cable 6 from the carriage 2 to the machining head 4 via an energy chain 11 known per se.

[0037] The energy chain 11 extends upwards in the z direction and is also referred to as a Z drag. In this chain, the cables described above are guided over a large number of flexible links. Starting from the carriage 2, the lines run vertically upwards into the Z drag, which deflects the lines by 180° and then guides them vertically downwards into a housing 5 of the machining unit 3, which is above the machining head 4. The energy chain 11 enables the lines guided therein to be shifted by changing their bending position when the machining head 4 or the machining unit 3 moves relative to the carriage 2.

[0038] In contrast to the embodiment described here, in conventional machining devices, the fibre cable 6 is supplied together with the other lines to the machining head 4 via the energy chain 11. It is disadvantageous here that the fibre cable generally has a significantly larger minimum bending radius than the other lines guided in the energy chain. Accordingly, the bending radius of the energy chain 11 must be set to the relatively large minimum bending radius of the fibre cable, which increases the vertical expansion of the energy chain. A machine roof that is usually provided must therefore be arranged at a greater height, which entails increased costs. In addition, the guiding of the fibre cable in the Z drag results in a greater length of this cable. Since certain fibre cable lengths must not be exceeded for the correct operation of the machining head 4, the scope for designing the laying of the fibre cable and, accordingly, the positioning of the laser source—because of the limited fibre length for the transmission of laser light with high power—is limited. In addition, longer fibre cables lead to increased manufacturing costs. Due to the absence of the fibre in the Z drag, it can be made smaller, as described above, which leads to a shortening of all cables and/or hoses guided therein. This can save additional costs.

[0039] In order to eliminate the above problems, in the embodiment described here, the fibre cable 6 is guided separately from the Z drag 11 to the machining head 4. Starting from the machining head 4, the fibre cable initially runs out of the machining head 4 in the horizontal y-direction and is then bent by 180° before it is rigidly fixed to the housing 5 of the machining unit 3 by means of a first fixing means 7, which is only indicated schematically. A fastening element known per se can be used as the fixing means 7; for example, a clamping device can be provided. The cable is then guided from the first fixing means 7 to a second fixing means 8, which is also only indicated schematically and can, for example, again be implemented by a clamping device. The second fixing means 8 is provided on the carriage 2 and thus ensures that the fibre cable is rigidly attached to the carriage.

[0040] An essential feature of the machining device of FIG. 1 is that the fibre cable 6 is freely movable between the first fixing means 7 and the second fixing means 8 without further fixing and in particular without an energy chain in a guide plane G parallel to the x-z plane of the coordinate system shown. In this way, a movement of the fibre cable during the vertical displacement of the machining unit 3 relative to the carriage 2 is made possible. However, in order to avoid undesired movement of the fibre cable when the carriage 2 is moved rapidly in the y-direction, the movement of the fibre cable between the fixing means 7 and 8 is limited with the aid of guide means 9 and 9′, which in the embodiment described here represent two parallel wall sections. The guide means form stop elements between which the fibre cable extends from the fixing means 7 to the fixing means 8. The guide means are part of the carriage 2 and run parallel to one another in planes which in turn are parallel to the x-z plane of the coordinate system shown. The fixing means 8 is located in the rear region of an upper edge of the guide means 9.

[0041] To protect the fibre cable 6, a cladding is also provided to the left of the machining head 4 and the housing 5. This cladding covers part of the fibre cable on its path from the machining head 4 to the guide means 9 and 9′. The cladding can be seen in FIG. 3 and is designated there by reference symbol 12. In order to make the cable guiding visible, the cladding has been omitted from the illustration in FIGS. 1 and 2.

[0042] In FIG. 1, the machining unit 3 or the machining head 4 is arranged in a first upper vertical position relative to the carriage 2. During the cutting process or the emitting of laser light by means of the machining head, the machining unit 3 is moved downwards together with the machining head 4 into a second, lower vertical position, which is indicated in FIG. 2. As can be seen in this figure, the machining head 4 is now located below the bridge 10, which is not the case in the position of FIG. 1. The vertical movement of the machining unit 3 is made possible with suitable actuators and vertical guiding of the machining unit on the carriage 4.

[0043] The vertical movement of the machining unit 3 into the position of FIG. 2 leads to a downward displacement of the first fixing means 7, which in turn leads to a stretching of the fibre cable 6 between the two fixing means 7 and 8. The free movement of the fibre cable between the fixing means can thus compensate for the change in the distance between the two fixing means. The extension of the fibre cable 6 between the guide means 9 and 9′ is illustrated in FIG. 2 by a dashed representation of the cable.

[0044] According to the embodiment of FIGS. 1 and 2, the fixing means 7 and 8 fix the fibre cable 6 in such a way that it runs in the horizontal direction at the location of the fixing means 8 and in the vertical direction at the location of the fixing means 7. In this way, it is achieved that the fibre cable 6 is deflected by an angle which is significantly smaller than 180°. In other words, the extension direction of the fibre cable 6 rotates starting from any point on the fibre cable between the fixing means 7 and 8 along the path of the fibre cable to any other point between the fixing means 7 and 8 about an angle that is significantly smaller than 180°. In this way, a short cable guiding is made possible between the carriage 2 and the machining head 4.

[0045] FIG. 3 again shows, in a schematic illustration, the overall structure of the laser machining tool 100, which contains the machining device 1 described above. In the illustration of FIG. 3, the laser machining tool is shown from a perspective which illustrates the cable guiding along the bridge 10 and the frame 14. From this perspective, the machining device 1 is positioned behind the bridge 10 and is partially covered thereby. Accordingly, the machining head 4, which is located behind the bridge 10, cannot be seen from FIG. 3. However, a part of the housing 5 as well as the Z drag 11 and the guide means or the wall section 9 by which the movement of the fibre cable is limited can be seen. In addition, the cladding 12 can be seen, in which a part of the fibre cable is located. For the sake of clarity of illustration, neither the fibre cable nor other lines are shown in FIG. 3.

[0046] According to FIG. 3, the fibre cable leaves the carriage 2 via a slot 13 behind the fixing means 8, which is not shown in FIG. 3. The fibre cable is then bent so that it enters an energy chain 17 which extends in the horizontal y-direction and is also referred to as a Y drag. The other lines that reach the machining head 4 via the Z drag 11 are also guided within this energy chain in a manner known per se. The energy chain 17 ensures that the lines or cables received therein are fed in when the carriage 2 is moved. From the Y drag, the cables pass via cable channels known per se, which are not explained in more detail here, to a further energy chain 18, which is also referred to as an X drag, and ensures the cables contained therein are fed in when the bridge 10 is moved in the x-direction. After leaving the X drag, the cables are guided either to a control cabinet 19 for controlling the laser machining tool or to the laser light source 16 already mentioned above, depending on their function. This cable guiding is not shown in FIG. 3 and is also not relevant for the invention.

[0047] The embodiment of the invention described above has a number of advantages. In particular, the fact that the minimum bending radius of the fibre cable is significantly larger than the minimum bending radius of other lines that reach the machining head via a Z drag is taken into account by separately guiding the fibre cable to the machining head. As a result, the vertical height of the Z drag can be reduced by reducing its bending radius when this drag is not guiding a fibre cable. In addition, by suitably fixing the fibre cable at two fixing points on the machining unit or on the carriage, the cable can be deflected by less than 180°, which enables shorter cable lengths. This in turn leads to lower costs as well as greater design freedom in cable guiding and the positioning of the laser source.

LIST OF REFERENCE SYMBOLS

[0048] 100 Laser machining tool

[0049] 1 Machining device

[0050] 2 Movable carriage

[0051] 3 Machining unit

[0052] 4 Machining head

[0053] 5 Housing

[0054] 6 Fibre cable

[0055] 7 First fixing means

[0056] 8 Second fixing means

[0057] 9, 9′ Guide means

[0058] 10 Bridge

[0059] 11 Z drag

[0060] 12 Cladding

[0061] 13 Slot

[0062] 14 Frame

[0063] 15, 15′ Frame support

[0064] 16 Laser light source

[0065] 17 Y drag

[0066] 18 X drag

[0067] 19 Control cabinet

[0068] G Guide plane