Abstract
A method for the quasi-simultaneous welding of at least two types of welding by means of a laser beam, wherein the laser beam originates from a laser optic which is associated with a platform of a delta robot and is guided by a movement of this platform.
Claims
1. Method for quasi-simultaneous welding of at least two welding locations with a laser beam, wherein the laser beam emanates from a laser optic which is associated with a platform of a delta robot and is guided by a movement of this platform.
2. Method according to claim 1, wherein the laser beam is guided by a combination of the movement of the platform and a further movement which is effected by a motion device associated with the platform.
3. Method according to claim 2, wherein at least one subunit of the motion device is moved relative to the platform in order to effect the further movement.
4. Method according to claim 3, wherein the at least one subunit is moved by a shaft.
5. Method according to claim 2, wherein the laser beam is deflected by at least one mirror arranged pivotably relative to the platform.
6. Method according to claim 2, wherein the laser optics are mounted movably relative to the platform in order to guide the laser beam.
7. Method according to claim 1, wherein a temperature of the plastic is measured by means of a pyrometer, a measurement result being used for evaluating and/or regulating the method.
8. Device for quasi-simultaneous welding of plastics, comprising a delta robot with a platform, wherein the platform being associated with laser optics.
9. Device according to claim 8, wherein the platform is further associated with a first end of an optical conductor which is connected to the laser optics, a second end of the optical conductor being connected to a laser, this laser being arranged outside the platform.
10. Device according to claim 8, wherein the laser optics is fixed to an element rotatably fixed to the platform.
11. Device according to claim 8, further comprising at least one mirror pivotally arranged relative to the platform.
12. Device according to claim 10, further comprising at least one shaft, a first end of which shaft is associated with the rotatable element or mirror adapted to cause movement of the rotatable element or mirror, a second end of which shaft is associated with a drive arranged outside the platform.
13. Device according to claim 8, further comprising a pyrometer.
14. Device according to claim 8, wherein the laser optics comprises half inch components.
15. Method according to claim 1, wherein the delta robot for quasi-simultaneous welds plastics.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0060] Further advantages, features and details of the invention result from the following description of preferred execution examples as well as from the drawings; these show in:
[0061] FIGS. 1a to 1d each a galvo scanner 9 according to the state of the art in different positions and components to be welded 10, 11
[0062] FIGS. 2a to 2d each a laser optic 2 of a device according to the invention, in different positions, as well as components to be welded 10, 11
[0063] FIG. 3 an example of an inventive device comprising a delta robot 1,
[0064] FIG. 4 another example of an inventive device comprising a delta robot 1,
[0065] FIG. 5 a platform 4 of an example of the execution of an inventive device comprising a gimbal suspension, and
[0066] FIG. 6 a platform 4 of another example of a device according to invention comprising two mirrors 15.1, 15.2.
DETAILED DESCRIPTION
[0067] The FIGS. 1a to 1d each show a galvo scanner 9. The course of a laser beam emanating from it in two different positions of the galvo scanner 9 is indicated by an arrow 3. Furthermore, a laser-transparent component 10 and a laser-absorbing component 11 are shown.
[0068] The FIGS. 2a to 2d each show a laser optic 2. The course of a laser beam emanating from it in two different positions of the laser optics 2 is indicated by an arrow 3. A laser-transparent component 10 and a laser-absorbing component 11 are also shown.
[0069] FIG. 3 shows the delta robot 1 comprising a base plate 5, three arms 8 and a platform 4. Delta robots 1 are known, therefore the detailed representation and designation of the rotatory drives, the joints and other known components was omitted.
[0070] A laser optic 2 is attached to platform 4, which is connected via an optical conductor 13 to a laser attached to the base plate 5 and not visible in the drawing.
[0071] The embodiment according to FIG. 4 differs from the embodiment according to FIG. 3 only in that the laser optics 2 is not connected to the platform 4 in a rotationally fixed manner, but is rotatably assigned to a motion device which is not further depicted via a subunit 19. The subunit 19 is connected to a drive 6 via a shaft 7.
[0072] FIG. 5 shows a platform 4 of a embodiment of an inventive device with a gimbal suspension comprising an outer ring 16 and an inner ring 17. The optical conductor 13 is recognizable approximately in the middle of the inner ring 17, the laser optics are not recognizable due to the perspective of FIG. 5.
[0073] FIG. 6 shows a platform 4 of another example of an inventive device comprising two mirrors 15.1, 15.2. The laser optics 2 with the optical conductor 13 are recognizable.
[0074] With reference to FIGS. 1 to 6, the function of the device according to the invention is explained as follows:
[0075] The well-known galvo scanner 9 according to FIGS. 1a to 1d can align the laser beam, which is indicated by arrow 3, or influence its spatial course, by swivelling at least one mirror that does not belong to the galvo scanner 9 and is not shown in detail. This is indicated by arrows 20.
[0076] In the FIGS. 1a to 1d, welding points or a welding seam should be created at the points where the arrows 3 hit the components 10, 11.
[0077] In FIG. 1a, the laser-transparent component 10 comprises a high component wall, resulting in beam shading, which in turn impairs the laser welding method.
[0078] In the arrangements according to FIGS. 1b and 1c, the laser-transparent component 10 comprises a connection 14 which is arranged next to (FIG. 1b) or above (FIG. 1c) an imaginary weld seam in such a way that a beam shading also occurs. A distance to be traversed by the laser beam is much larger in the case of such a beam shading through connection 14 than the distance to be traversed at other points of the laser-transparent component 10. Furthermore, the laser beam can be refracted through any curved walls of connection 14. It is therefore not possible to carry out the laser welding method in such a way that the laser beam simply passes through port 14 at the appropriate points in order to produce the weld seam.
[0079] In the arrangement shown in FIG. 1d, the components 10, 11 are convex, which leads to an unfavourable angle of incidence of the laser beam indicated by arrow 3. In comparison to FIG. 1c, for example, FIG. 1d clearly shows that the angle of incidence or the angle 21 at which the laser beam 3 impinges on the components 10, 11 is significantly smaller. The same applies to a comparison with FIGS. 1a and 1b, in which angle 21 is not shown for the sake of clarity.
[0080] As shown in FIGS. 2a to 2d, the inventive device overcomes the problems shown in FIGS. 1a to 1d.
[0081] Laser optics 2 can take the positions shown in FIGS. 2a and 2b because it is attached to platform 4. This makes it possible to position the laser optics 2 above the components 10, 11 by corresponding movement of the platform 4 in such a way that the laser beam indicated by the arrows 3 impinges essentially perpendicularly on an interface between the laser-transparent component 10 and the laser-absorbing component 11, as shown in FIGS. 2a and 2b. Thus, neither a high component wall of the laser-transparent component 10 shown in FIG. 2a nor a connection 14, which is arranged next to the weld seam to be produced according to FIG. 2b, leads to a beam shading.
[0082] FIGS. 2c and 2d show that a movement of the laser optics 2, which for example can be caused by a subunit 19 of a motion device (not shown), helps to overcome the problems shown in the corresponding FIGS. 1c and 1d.
[0083] FIGS. 2c and 2d show that the spatial course of the laser beam can be influenced not only by the spatial orientation or movement of platform 4, but also by a movement of laser optics 2 relative to platform 4. Thus, the connection 14 in FIG. 2c arranged above the weld seam does not present a problem either, because a combination of movement of platform 4 and movement of laser optics 2 in relation to platform 4 results in no beam shading.
[0084] The same applies to the convex components 10, 11 in FIG. 2d, so that the angle 21, in contrast to the corresponding angle 21 in FIG. 1d, is much closer to a preferred right angle.
[0085] As can be seen from FIGS. 2a to 2d, platform 4 of the not shown Delta robot always lies in the same imaginary plane and does not incline, regardless of its position. This is due to the parallel kinematics of the delta robot.
[0086] It should be noted that instead of moving the laser optic 2 relative to platform 4 as shown in FIGS. 2c and 2d, it may also be thought of deflecting the laser beam through at least one mirror without moving the laser optic 2. An arrangement comprising at least one mirror can achieve the same result as shown in FIGS. 2c and 2d.
[0087] The forms of execution of the present invention shown in FIGS. 3 and 4 are suitable for carrying out the operations shown in FIGS. 2a to 2d by moving arms 8 and, if necessary (FIG. 4), laser optics 2 in relation to platform 4. It should be mentioned here that the laser beam indicated by arrow 3 is generated by a laser arranged below the base plate 5 and therefore not visible in FIGS. 3 and 4, the laser optics 2 being connected to the laser via an optical conductor 13.
[0088] The subunit 19, which in the arrangement shown in FIG. 4 causes the movement of the laser optics 2 relative to the platform 4, is driven by a shaft 7, which is connected to a drive 6.
[0089] By not placing the laser and drive 6 on platform 4, the weight of platform 4 can be kept as low as possible.
[0090] With respect to FIG. 3, it should be noted that the laser beam indicated by arrow 3 is always at a certain angle to platform 4, since the laser optics 2 are rotationally fixed to platform 4. However, this does not have to be a right angle as in the embodiment according to FIG. 3, according to which the laser beam is orthogonal to an imaginary plane within which the platform 4 lies.
[0091] In the form shown in FIG. 5, the (not visible) laser optic 2 is fixed to the inner ring 17 of the gimbal suspension. By rotating the outer ring 16 around the rotation axis 12.2 and rotating the inner ring 17 around the rotation axis 12.1, it is possible to move the laser optics 2 with respect to the imaginary plane within which the platform 4 lies. As already described, the spatial course of the laser beam can thus be influenced.
[0092] The rotation around the rotation axes 12.1, 12.2 is indicated by arrows. Cardanic suspensions and their function are sufficiently known from the state of the art. The rotation of the rings 16, 17 preferably takes place via one shaft each (not shown), so that the associated drive, which causes the rotation, does not have to be arranged on platform 4.
[0093] In the version shown in FIG. 6, the laser optic 2 is rotationally fixed to the platform 4. In order to nevertheless change the spatial orientation of the laser beam relative to platform 4, it is directed onto a first mirror 15.1, reflected by it and then directed onto a second mirror 15.2, from which it is also reflected. By rotating the first mirror 15.1 around an axis of rotation orthogonal to the platform plane (not shown, indicated by a double arrow next to the mirror 15.1), the beam can be directed, indicated by arrows 3, to different sections or locations of the second mirror 15.2. Two alternative courses are indicated by dashed arrows 3, which start from the first mirror 15.1. The second mirror 15.2 can rotate around the rotation axis 12 and thus deflect the beam again, depending on the rotation performed. The arrangement shown in FIG. 6 as well as the arrangement shown in FIG. 5 allows to change the course of the laser beam relative to platform 4.
[0094] The mirrors 15.1, 15.2. are preferably galvo mirrors.
REFERENCE NUMBER LIST
[0095] 1Delta robot [0096] 2Laser optics [0097] 3Arrow [0098] 4Platform [0099] 5Base plate [0100] 6Drive [0101] 7Shaft [0102] 8Arm [0103] 9Galvo Scanner [0104] 10Laser transparent component [0105] 11Laser-absorbing component [0106] 12Rotary axis [0107] 13Optical conductor [0108] 14Connection [0109] 15Mirrors [0110] 16Outer ring [0111] 17Inner ring [0112] 18Rotary axis [0113] 19Subunit [0114] 20Arrow [0115] 21Angle
