ALIGNMENT UNIT, SENSOR MODULE COMPRISING SAME, AND LASER WORKING SYSTEM COMPRISING THE SENSOR MODULE

Abstract

An alignment module coupling a sensor unit to a laser machining device for monitoring a laser machining process is provided. The module includes a first coupling device with a first optical input for a process radiation coupled out of the laser machining device and a coupling element for coupling to the machining device; a second coupling device with a first optical output and a coupling element for coupling to the sensor unit; a first adjustment module arranged between the first and second coupling devices and configured to tilt and/or displace the coupling devices with respect to one another; and a focusing optics between the first optical input and the first optical output, which is slidably disposed along the optical axis of the focusing optics. A sensor module monitoring a laser machining process is provided, which includes the alignment module. A laser machining system is also provided, including the sensor module.

Claims

1. An alignment module for coupling a sensor unit to a laser machining device for monitoring a laser machining process, said alignment module comprising: a first coupling device for coupling to said laser machining device, said first coupling device including a first optical input for a process radiation coupled out of said laser machining device; a second coupling device for coupling to said sensor unit, said second coupling device including a first optical output for the process radiation; a first adjustment module, which is arranged between said first coupling device and said second coupling device and is configured to tilt said second coupling device relative to said first coupling device and/or displace said second coupling device in at least one direction perpendicular to a central axis of said first optical input; and a focusing optics which is arranged between said first optical input and said first optical output and is displaceable along an optical axis of said focusing optics.

2. The alignment module according to claim 1, wherein said first adjustment module is configured to adjust an angle and/or an offset between the central axis of said first optical input and a central axis of said first optical output.

3. The alignment module according to claim 1, wherein said first adjustment module comprises a ball joint, a linear guide, a piezoelectric element and/or a micrometer screw.

4. The alignment module according to claim 1, wherein said focusing optics is displaceable along the central axis of said first optical input or along the central axis of said first optical output.

5. The alignment module according to claim 1, further comprising a second adjustment module for adjusting a position of said focusing optics, wherein said second adjustment module includes a holder of said focusing optics and a guide element with which said holder is coupled so as to be slidable along the optical axis of said focusing optics.

6. The alignment module according to claim 5, wherein the guide element is fixedly connected to said first coupling device or fixedly connected to said second coupling device.

7. A sensor module for a laser machining system for monitoring a laser machining process, said sensor module comprising: an alignment module according to claim 1; and a sensor unit including a second optical input for the process radiation emerging from said alignment module, a coupling element which is coupled to said second coupling device of said alignment module and couples said second optical input to said first optical output of said alignment unit, and at least one detector for detecting the process radiation, wherein said alignment module is configured to align a central axis of said second optical input of said sensor unit to a process radiation entering said first optical input of said first coupling device.

8. The sensor module according to claim 7, wherein said sensor unit comprises a detector arranged on the central axis of said second optical input.

9. The sensor module according to claim 8, wherein said sensor unit further comprises: at least one further detector arranged at a distance from the central axis of said second optical input; and at least one beam splitter which is arranged on the central axis of said second optical input an is configured to couple a partial beam out of the process radiation and to direct it to said further detector.

10. The sensor module according to claim 9, wherein the detectors are each configured to detect different wavelengths of the process radiation, and/or wherein said beam splitter is configured to reflect or transmit partial beams with a specific wavelength.

11. The sensor module according to claim 7, wherein the at least one detector of said sensor unit is calibrated for rays along the central axis of said second optical input of said sensor unit.

12. The sensor module according to claim 7, wherein said sensor unit further comprises: a control unit configured to receive analog measurement signals from the at least one detector and convert them into digital measurement signals.

13. The sensor module according to claim 7, wherein said sensor unit is detachably attached to said alignment module or is formed integrally with said alignment module.

14. A laser machining system, comprising: a sensor module according to claim 7; and a laser machining device for machining a workpiece by a laser beam, said laser machining device including a process radiation output and a coupling element which is coupled to said first coupling device of said alignment module and couples the process radiation output of said laser machining device to said first optical input of said alignment module unit.

15. The laser machining system according to claim 14, wherein said laser machining device further comprises a beam splitter for coupling process radiation out of the beam path of the laser beam of said laser machining device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The invention is described in detail below with reference to figures. In the figures;

[0039] FIG. 1 shows a schematic diagram of a laser machining system for machining a workpiece by means of a laser beam according to embodiments of the present disclosure;

[0040] FIG. 2 shows a schematic diagram of a sensor module for a laser machining system for monitoring a laser machining process according to embodiments of the present disclosure; and

[0041] FIG. 3 is a schematic diagram of an alignment module for coupling a sensor unit to a laser machining device for monitoring a laser machining process according to embodiments of the present disclosure.

DETAILED DESCRIPTION OF THE DRAWINGS

[0042] Unless otherwise noted, the same reference symbols are used for identical and equivalent elements below.

[0043] FIG. 1 shows a schematic diagram of a laser machining system for machining a workpiece by means of a laser beam according to embodiments of the present disclosure. FIG. 2 shows a schematic diagram of a sensor module for a laser machining system for monitoring a laser machining process according to embodiments of the present disclosure.

[0044] The laser machining system 1 comprises a laser machining device 10 and a sensor module 20.

[0045] The laser machining device 10, which may be configured as a laser machining head, for example, is configured to focus or collimate a laser beam (not shown) emerging from a laser light source or an end of a laser optical fiber onto a workpiece 14 to be machined using a beam guiding and focusing optics (not shown) to thereby perform machining or machining process. Machining may comprise laser cutting, soldering or welding, for example.

[0046] During machining, process radiation 11 is created which enters laser machining device 10 and is coupled out of a beam path of the laser beam (not shown) by a beam splitter 12. The laser machining device 10 includes a coupling element 13 and an optical output (not shown). The optical output or process radiation output may be combined with the coupling element 13. The process radiation 11 is coupled out of the process radiation output of the laser machining device 10.

[0047] The sensor module 20 comprises an alignment module 100 and a sensor unit 200.

[0048] The alignment module 100 includes a first coupling device 110 and a second coupling device 120. The first coupling device 110 includes a coupling element (not shown) and a first optical input 111. The second coupling device 120 includes a further coupling element (not shown) and a first optical output 121. Furthermore, the alignment module 100 includes a focusing optics 130 displaceable along its optical axis in order to adjust a focal position.

[0049] The sensor unit 200 typically includes a plurality of detectors or sensors 220 which are configured to detect various parameters of the process radiation 11 such as an intensity and to output a measurement signal based on the detection. The sensor unit 200 also includes a coupling element 210 and a second optical input 211. The second optical input 211 may be formed in combination with the coupling element 210.

[0050] The coupling element of the first coupling device 110 is connected to the coupling element of the laser machining device 10. Thus, the alignment module 100 is coupled to the laser machining device 10. In other words, the process radiation output of the laser machining device 10 is coupled to the first optical input 111 of the alignment module 100.

[0051] The coupling element of the second coupling device 120 is connected to the coupling element 210 of the sensor unit 200. Thus, the alignment module 100 is coupled to the sensor unit 200. In other words, the first optical output 121 of the alignment module 100 is coupled to the second optical input of the sensor unit 200.

[0052] Thus, the sensor unit 200 is coupled to the laser machining device 10 via the alignment module 100. Here, the alignment module 100 has the function of an adapter. In the state shown in FIG. 1, the process light 11 emerging from the process radiation output of the laser machining device 10 is incident on the first optical input 111 of the alignment module 100. It then emerges from the first optical output 121 of the alignment module 100 and enters the second optical input 211 of the sensor unit 200. In the sensor unit 200, it hits the at least one detector 220.

[0053] The alignment module 100 includes a focusing optics 130 arranged in the beam path of the process radiation 11 between the first optical input 111 and the second optical output 121 of the alignment module 100. Furthermore, the alignment module 100 includes a first adjustment module 140 arranged between the first coupling device 110 and the second coupling device 120. The first adjustment module 140 is configured to tilt the first coupling device 110 and the second coupling device 120 relative to one another or to displace them relative to one another in at least one direction. As a result, the first optical input 111 and the first optical output 121 of the alignment module 100 are also tilted or displaced relative to one another. This in turn leads to the alignment of the process radiation 11 in relation to the first optical output 121 of the alignment module 100 and to the second optical input 211 of the sensor unit 200 being changed.

[0054] As a result, the process radiation 11 may be adjusted with respect to a central axis of the second optical input 211 of the sensor unit 200, for example. In particular, the process radiation 11 may be aligned with the central axis of the second optical input 211. In other words, it may extend in parallel to a central axis of the optical input 211.

[0055] By means of the focusing optics 130 of the alignment module 100, the process radiation 11 may also be focused or a defined or predetermined focal position may be set.

[0056] As shown in FIG. 2, the first adjustment module 140 may comprise a ball joint. The joint socket of the ball joint is connected to the first coupling device 110. According to embodiments, the joint socket of the ball joint and the first coupling device 110 are formed integrally. The joint socket of the ball joint is connected to the second coupling device 120. According to embodiments, the joint socket of the ball joint and the second coupling device 120 are formed integrally.

[0057] The ball joint allows an orientation or alignment of the second coupling device 120 with respect to the first coupling device 110 to be adjusted. The alignment may be carried out in two spatial directions or spatial angles θ, ∂.

[0058] As shown in FIG. 2, the focusing optics 130 may include a focusing lens. The focusing lens is displaceable or adjustable along or in parallel to a Z direction. According to embodiments, the Z direction corresponds to an optical axis of the focusing optics 130. The optical axis of the focusing optics 130 may correspond to a central axis of the first coupling device 110 or the first optical input 111 or a central axis of the second coupling device 120 or the first optical output 121.

[0059] As shown in FIG. 2, the sensor unit 120 comprises a plurality of detectors 220a, 220b, 220c. Each of the detectors 220a, 220b, 220c may comprise a photodiode or a photodiode array or pixel array.

[0060] Furthermore, the sensor unit 200 comprises a plurality of beam splitters 230a, 230b to split up or divide the process radiation 11. As shown in FIG. 2, the beam splitters 230a, 230b may configured as partially transparent mirrors. The beam splitters 230a, 230b are each configured to couple at least one partial beam 11a, 11b, 11c out of the process radiation 11. As shown in FIG. 2, the beam splitter 230a couples the partial beam 11a, which hits the detector 220a, out of the process radiation 11. The beam splitter 230b couples the partial beams 11b and 11c out of the process radiation 11, the partial beam 11b hitting the detector 220b and the partial beam 11c hitting the detector 220c.

[0061] According to embodiments, the beam splitters 230a, 230b may be wavelength selective. In other words, the beam splitters 230a, 230b may couple the partial beams 11a, 11b, 11c out of the process radiation 11 in a wavelength-selective manner. For example, the beam splitter 230a may be configured to couple out light in the visible spectrum as a partial beam 11a and the beam splitter 230b may be configured to couple out light in the infrared spectrum as a partial beam 11b. In this case, the partial beam 11c may contain light which has a wavelength range of the laser beam of the laser machining device 10. As a result, an improved or optimal light yield may be obtained by the respective detector 220a, 220b, 220c since only light with a specific wavelength or wavelength range hits the respective detector 220a, 220b, 220c.

[0062] The detectors 220a, 220b, 220c are configured to detect the respective impinging partial beam 11a, 11b, 11c. The detectors 220a, 220b, 220c are configured, in particular, to detect a parameter of the respective partial beam 11a, 11b, 11c. In particular, the detectors 220a, 220b, 220c may be configured to detect an intensity of the respective partial beam 11a, 11b, 11c. The detectors 220a, 220b, 220c are configured to generate and output a measurement signal based on the detection. The measurement signal may be an analog voltage signal, for example.

[0063] The sensor unit 200 also comprises a control unit 240. The control unit 240 is connected to the detectors 220a, 220b, 220c and receives the measurement signals from the detectors 220a, 220b, 220c. The control unit 240 is configured to convert the analog measurement signals into digital measurement signals and to provide the digital measurement signals at an interface (not shown).

[0064] The detectors 220a, 220b, 220c are arranged in the beam path of the respective partial beams 11a, 11b, 11c such that a focal position or focal point of the partial beams 11a, 11b, 11c coincides with a surface of the detectors 220a, 220b, 220c. In other words, the detectors 220a, 220b, 220c are arranged such that, for a process radiation 11 coupled into the sensor unit 200 with a predetermined alignment and a predetermined focal position, the position of the detectors 220a, 220b, 220c coincides with the focal point of the respective partial beams 11a, 11b , 11c. In particular, the partial beams 11a, 11b, 11c may have the same optical path length between the optical input 211 of the sensor unit 200 and the respective detector 220a, 220b, 220c.

[0065] As described above, the predetermined alignment of the process radiation 11 may be such that the process radiation 11 is aligned with a central axis of the optical input 211 of the sensor unit 200 or extends in parallel or coaxially thereto.

[0066] As shown in FIG. 2, the detectors 220a, 220b, 220c can each be adjusted in two directions. That is, the position of the detectors 220a, 220b, 220c can be adjusted in two directions. For example, the two directions may each be perpendicular to a beam axis of the partial beams 11a, 11b, 11c. In particular, the detector 220a can be displaced in a plane perpendicular to the beam axis of the partial beam 11a, the detector 220b can be displaced in a plane perpendicular to the beam axis of the partial beam 11b, and the detector 220c can be displaced in a plane perpendicular to the beam axis of the partial beam 11c. As shown in FIG. 2, the detector 220a may be displaced in the X, Z directions with the partial beam 11a extending in parallel to the Y direction, the detector 220b can be displaced in the X, Z directions with the partial beam 11b extending in parallel to the Y direction, and the detector 200c can be displaces in the directions X, Y with the partial beam 11c extending in parallel to the Z direction. The X, Y and Z directions may correspond to coordinate axes of a Cartesian coordinate system, the Z direction being chosen along the optical axis of the focusing optics 130 in this example. The described adjustability of the detectors 220a, 220b, 220c makes it possible to set or adjust each of the detectors to a beam axis of the partial beams 11a, 11b, 11c. The adjustment may be performed during the production of the sensor unit 200, for example. The adjustment makes it possible for the partial beams 11a, 11b, 11c to hit the detectors 220a, 220b, 220c in an optimal manner, in particular centered on a detector surface of the detectors 220a, 220b, 220c.

[0067] FIG. 3 shows a schematic diagram of an alignment module for coupling a sensor unit to a laser machining device for monitoring a laser machining process according to other embodiments of the present disclosure.

[0068] The embodiment of the alignment module 100 shown in FIG. 3 includes a first coupling device 110, a second coupling device 120, a first adjustment module 140 and a focusing optics 130.

[0069] The first coupling device 110 comprises an optical input 111 with a central axis 112. The second coupling device 120 comprises an optical output 121 with a central axis 122.

[0070] The first adjustment module 140 corresponds to the embodiment shown in FIG. 2, and a description thereof is omitted.

[0071] The focusing optics 130 is configured as a focusing lens. The alignment module 100 further includes a second adjustment module 150. The adjustment module 150 includes a holder 151 holding the focusing optics 130. The focusing optics 130 has an optical axis 133. As shown in FIG. 3, the optical axis 133 extends coaxially or in parallel to the central axis 112 of the first optical input 111. According to other embodiments, the optical axis 133 may extend coaxially or in parallel to the central axis 122 of the first optical output 121.

[0072] The focusing optics 130 is displaceable along the optical axis 133 of the focusing optics 130 using the holder 151. The focusing optics 130 may further comprise a guide element (not shown), for example a rail, for guiding the holder 132 along the optical axis 133. According to embodiments, the lens 130 may also be displaceable along or in parallel to the central axis 112 of the optical input 111.

[0073] As shown in FIG. 3, the holder 151 is slidably connected to the first coupler 110. The guide element may be formed integrally with the first coupling device 110.

[0074] The second coupling device 120 is pivotable or tiltable along the direction 123 with respect to the first coupling device 110 using the first adjustment module 140, which may be configured as a ball joint. The second coupling device 120 may further be pivotable or tiltable along a second direction (not shown) with respect to the first coupling device 110. By tilting the second coupling device 120, the process radiation (not shown in FIG. 3), which enters the alignment module 100 at an angle relative to the central axis 112 of the optical input 111, may be aligned with the central axis 122 of the optical output 122 of the second coupling device 120. The process radiation may thus emerge from the alignment module 100 coaxially or in parallel to the central axis 122 of the optical output 121. As a result, in turn, the process radiation has a defined alignment when entering the second optical input of the sensor unit connected to the alignment module 100 (not shown in FIG. 3). In particular, the process radiation may be aligned with the central axis of the second optical input of the sensor unit.

[0075] The alignment module provided between an optical output of the laser machining device and an optical input of the sensor unit makes it possible to align the process radiation with a central axis of the optical input of the sensor unit and to set a defined focal position of the process radiation. In other words, the sensor unit as a whole can be adjusted or aligned to the focus position and/or alignment of the process radiation coupled out by the laser machining device. As a result, individual detectors of the sensor unit no longer have to be individually adjusted to the process radiation of a respective laser machining device, but can be adjusted in advance, e.g. during manufacture of the sensor unit, to process radiation aligned with the central axis of the optical input of the sensor unit. This also allows for factory calibration of the detectors to a reference light source.