ULTRASONIC WELDING DEVICE WITH INTEGRATED CAMERA ASSEMBLY

Abstract

An ultrasonic welding device includes a sonotrode, an anvil, a receiving chamber in which joining partners to be welded are to be received and which is defined on opposing sides by the sonotrode on the one hand and by the anvil on the other hand, and a camera assembly with at least one camera which is integrated in the ultrasonic welding device. The camera assembly is configured to record images of at least one partial region of the receiving chamber for the optical monitoring of welding conditions which have an impact on welds of the joining partners.

Claims

1-13. (canceled)

14. An untrasonic welding device, comprising: a sonotrode; an anvil; a receiving chamber in which joining partners to be welded are to be received and which is defined on opposing sides by the sonotrode on the one hand and by the anvil on the other hand; a camera assembly with at least one camera which is integrated in the ultrasonic welding device; wherein the camera assembly is configured to record images of at least a partial region of the receiving chamber for the optical monitoring of welding conditions which have an impact on welds of the joining partners.

15. The ultrasonic welding device according to claim 14, wherein the camera assembly is arranged outside the receiving chamber and is configured to record the images of the partial region of the receiving chamber from one side in relation to a surface of the sonotrode defining the receiving chamber.

16. The ultrasonic welding device according to claim 14, further comprising a light source which is configured to illuminate the partial region of the receiving chamber in which the images are to be recorded by the camera assembly.

17. The ultrasonic welding device according to claim 16, wherein the light source comprises a plurality of illuminants arranged in a distributed manner

18. The ultrasonic welding device according to claim 16, wherein the light source is configured to illuminate the partial region of the receiving chamber predominantly with diffuse light.

19. The ultrasonic welding device according to claim 16, wherein the light source is configured to selectively illuminate the partial region of the receiving chamber with light of different colors.

20. The ultrasonic welding device according to claim 16, wherein the light source is configured to illuminate the partial region of the receiving chamber with a light pattern.

21. The ultrasonic welding device according to claim 14, wherein the camera system comprises a second camera which is arranged spaced apart from the first camera of the camera system.

22. The ultrasonic welding device according to claim 21, wherein the first and the second cameras are arranged on opposing sides of the receiving chamber along an insertion direction in which the joining partners are to be inserted into the receiving chamber and are configured to record images of the partial region of the receiving chamber at different oblique angles in relation to a surface of the sonotrode defining the receiving chamber.

23. The ultrasonic welding device according to claim 14, wherein the camera assembly further comprises an image evaluation device which is configured to evaluate images recorded with the camera assembly in order to generate data with the aid of which the welding conditions are to be assessed.

24. The ultrasonic welding device according to claim 23, wherein the image evaluation device is configured to spatially evaluate the images recorded with the camera assembly in such a manner that data generated thereby contain information about the welding conditions which is location-dependent in three dimensions.

25. The ultrasonic welding device according to claim 14, wherein the camera assembly is composed in a modular manner of a plurality of components which are replaceable as necessary.

26. The ultrasonic welding device according to claim 14, wherein components of the ultrasonic welding device are replaceable, wherein each of the components has optically recognizable features which characterize it individually, and wherein the camera assembly is configured to recognize the optically recognizable features by evaluating the images recorded with the camera assembly and to provide information about a respective component on the basis thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Advantageous embodiments of the invention are further explained below with reference to the accompanying drawings, and neither the drawings nor the explanations are to be construed as limiting the invention in any way.

[0068] FIG. 1 shows a greatly simplified lateral view of an ultrasonic welding device according to an embodiment of the present invention.

[0069] FIG. 2 shows a perspective view of a partial region of an ultrasonic welding device according to an embodiment of the present invention.

[0070] FIG. 3 shows a perspective view of a detail of an ultrasonic welding device according to an embodiment of the present invention, with a view into the camera assembly thereof.

[0071] FIG. 4 shows a plan view of the detail shown in FIG. 3.

[0072] FIG. 5 illustrates viewing ranges of cameras in a camera assembly of an ultrasonic welding device according to an embodiment of the present invention.

[0073] FIG. 6 illustrates a modular construction of a camera assembly of an ultrasonic welding device according to an embodiment of the present invention.

[0074] The figures are merely schematic and not to scale. Identical reference numerals in the various drawings denote identical features or features having the same effect.

DETAILED DESCRIPTION

[0075] FIG. 1 shows, in a greatly simplified manner, an ultrasonic welding device 1 according to an embodiment of the present invention. FIG. 2 shows a perspective view of a receiving chamber 13 of the ultrasonic welding device 1 in a specific embodiment.

[0076] The ultrasonic welding device 1 comprises a sonotrode 3, an anvil 5, a touching element 7 and a lateral slide 9. Said components 3, 5, 7, 9 surround in a frame-like manner the receiving chamber 13 in which joining partners 15, such as a first strand 17 of a first cable and a second strand 19 of a second cable, may be received. The receiving chamber 13 is defined at the bottom by a surface 21 of the sonotrode 3, at the top by a surface 23 of the anvil 5, on the right by a surface 25 of the touching element 7 and on the left by a surface 27 of the lateral slide 9. The receiving chamber 13 defined in a frame-like manner by said surfaces 21, 23, 25, 27 is thus approximately cuboid. The receiving chamber 13 is open at the front and at the rear, so that, for example, the two strands 17, 19 can be inserted into the receiving chamber 13 from the front in an insertion direction 49.

[0077] In the example shown, the receiving chamber 13 can be defined on a rear side by a displaceable stop element 11, which may be moved by a drive device 29 in a displacement direction 31 behind the receiving chamber 13 in such a manner that the joining partners 15 can be aligned with their front faces on a surface 33 of the stop element 11 directed toward the receiving chamber 13.

[0078] Functions and/or displacements of the various activatable and/or displaceable components 3, 5, 7, 9, 11 of the ultrasonic welding device 1 may be controlled by a control system 35.

[0079] The joining partners 15 are if possible to be arranged in the receiving chamber 13 in an advantageous position relative to each other before they are welded together. However, the receiving chamber 13 is relatively small and is difficult to see into from outside, so that an operator of the ultrasonic welding device 1 must be experienced and particularly well trained in order to be able to reliably position the joining partners 15 correctly in the receiving chamber 13.

[0080] As is shown schematically in FIG. 1 and in more detail in FIG. 3-6, a camera assembly 37 is therefore provided outside the receiving chamber 13. The camera assembly 37 is designed to record images at least of a partial region 41 of the receiving chamber 13 by means of at least one camera 39. On the basis of these images, welding conditions which have an impact on the welds of the joining partners 15 that are produced during a welding process may then be monitored. In order to be able to improve the quality of and/or the information contained in these images, the camera assembly 37 may comprise a light source 43 by means of which the partial region 41 to be imaged may be illuminated. The camera assembly 37 may further be of modular construction, wherein components of the camera assembly 37 such as, for example, its camera 39, its light source 43 and possible other components are replaceably held in a housing 45, and the housing 45 is held on a fixed structure 47 of the ultrasonic welding device 1, for example. Functions of the camera assembly 37 may be controlled by the control system 35, for example.

[0081] FIG. 3-6 illustrate possible forms of the camera assembly 37 with regard to the components used therein, its geometry and its arrangement within the ultrasonic welding device 1. The housing 45 of the camera assembly 37 has not been shown in FIG. 3-5, and instead the components accommodated therein are shown.

[0082] As is shown in perspective in FIG. 3 and in a plan view in FIGS. 4 and 5, the camera assembly 37 comprises an elongate, curved holding assembly 51. The elongate holding assembly 51 extends parallel to the insertion direction 49 and is arranged above the anvil 5. Two cameras 39 and a plurality of illuminants 53, which together form the light source 43, are arranged on or in the holding assembly 51. The holding assembly 51 is fastened to the fixed structure 47 of the ultrasonic welding device 1.

[0083] A front camera 39′ is arranged obliquely above and in front of the receiving chamber 13 in the insertion direction 49, whereas a rear camera 39″ is arranged obliquely above and behind the receiving chamber 13. The two cameras 39′, 39″ are oriented with their viewing axes 55′, 55″ (see FIGS. 3 and 4) obliquely toward the partial region 41 of the receiving chamber 13 to be observed, so that their conical viewing regions 57′, 57″ (see FIG. 5) at least overlap on the partial region 41 and may thus record images of joining partners 15 received therein (not shown in FIG. 3-5 for reasons of clarity) from different directions and angles.

[0084] In the example shown, the camera assembly 37 has five illuminants 53 in the form of LEDs, which are arranged on the holding assembly 51 spatially distributed in the insertion direction 49 and equidistantly one behind the other. The illuminants 53 serve to illuminate the partial region 41 to be imaged. The illuminants 53 may optionally be different in terms of the light color they emit or may be color tunable, so that the light emitted by the light source 43 may be varied in terms of color.

[0085] The holding assembly 51 preferably consists of a transparent material such as a clear plastics material. The cameras 39 may be held in the holding assembly 51 in such a manner that they are able to “see” the partial region 41 to be imaged with their viewing regions 57 through openings 59 in the holding assembly 51 and thus unhindered by the transparent material. In contrast, the illuminants 53 may be accommodated in the holding assembly 51 in such a manner that the light emitted thereby must first pass through the transparent material of the holding assembly 51 before it can then reach the partial region 41. The holding assembly 51 may be configured in such a manner that the transmitted light does not strike the partial region 41 predominantly as directed light but rather as diffuse light. For this purpose, light-scattering particles may be contained in the transparent material, for example, and/or surfaces of this material may be roughened so that they scatter light. As a result, the partial region 41 may be illuminated largely homogeneously and interfering local reflections at surrounding components of the ultrasonic welding device 1 may largely be avoided.

[0086] The holding assembly 51 or an additional optical component (not shown) to be mounted thereon, for example, may further be configured to provide the light generated by the light source 43 with a light pattern. For this purpose, regions which absorb and/or optically refract to a greater or lesser extent may be arranged adjacent to one another in the holding assembly 51 or the additional component, in order to produce lighter and darker regions and/or regions of different colors in the transmitted light. By illumination with a light pattern so produced, for example a striped pattern, structures within the partial region 41 to be imaged may better be recognized and the recorded images may optionally be evaluated in respect of their spatial arrangement.

[0087] For evaluating the images, the control system 35, for example, may comprise an image evaluation device 61. The image evaluation device may receive image data from the camera assembly 37 and generate from the recorded images, for example by image analysis, data with the aid of which the welding conditions to be observed may be assessed. In this case, the image evaluation device 61 may preferably even spatially evaluate the images in order to be able to determine information about the welding conditions location-dependently in three dimensions.

[0088] In FIG. 6, the modular construction of the camera assembly 37 is illustrated by way of example. In this case, the holding assembly 51 is accommodated inside a two-part housing 45. Thus, the holding assembly 51 and/or the cameras 39 accommodated therein as well as the illuminants 53 accommodated therein may easily be replaced in order to allow the camera assembly 37 to be adapted, for example, for modified illumination conditions.

[0089] In summary, and partially with a different wording, embodiments of the ultrasonic welding device 1 described herein may be explained as follows: By the arrangement of the cameras, which constitute an integral part of the ultrasonic welding device, the insertion process may easily be monitored and the operator may be made aware of possible insertion errors. Furthermore, in the case of closed tools (anvil pulled out and at the bottom, lateral slide pulled in), the position also allows both sides of cables serving as joining partners to be seen and to be checked for incorrect positioning, protruding wires, displacements, etc. However, owing to the limited installation space, the light conditions are very unfavorable and make reliable recognition possible only with difficulty. Moreover, the influence of ambient light is very great. However, by means of the LEDs arranged in the curve and the illuminating body acting in a curved manner as a holding assembly and the material/surface thereof, uniform illumination of the welding chamber serving as the receiving chamber is produced, whereby reliable evaluation is often only then possible. The illuminating body may be partially hollow, in order to generate light that is as diffuse as possible. As a result of the modular construction, it is also easily possible to respond to different requirements (e.g. different tools, welding position, light conditions. . . ) and to adapt the system in a simple manner For referencing, geometries (edges, radii. . . ) on the tools or additional markings are used. The geometries or markings (optionally text, barcode. . . ) may additionally be used to recognize whether the correct tools have been fitted. Wires jammed between the anvil and the lateral slide may be recognized via a gap between the two tools. By means of the arrangement of the cameras it is additionally also possible to measure the cables or the welded splices three-dimensionally. These measured values may then be used as a good/bad criterion for quality control. By means of different illuminating means (striped pattern, different colors, etc.) it is additionally possible to recognize surface forms and optionally contamination (e.g. copper deposits on the tools) and to propose necessary maintenance/cleaning to the user.

[0090] Finally, it should be noted that terms such as “having”, “comprising”, etc. do not exclude any other elements or steps and the term “one” does not exclude a plurality. It should further be pointed out that features or steps which have been described with reference to one of the above exemplary embodiments may also be used in combination with other features or steps of other exemplary embodiments described above. Reference numerals in the claims are not to be regarded as a limitation.

LIST OF REFERENCE NUMERALS

[0091] 1 Ultrasonic welding device

[0092] 2 Sonotrode

[0093] 5 Anvil

[0094] 7 Touching element

[0095] 9 Lateral slide

[0096] 11 First stop element

[0097] 13 Receiving chamber

[0098] 15 Joining partner

[0099] 17 First strand

[0100] 19 Second strand

[0101] 21 Surface of the sonotrode

[0102] 23 Surface of the anvil

[0103] 25 Surface of the touching element

[0104] 27 Surface of the lateral slide

[0105] 29 Drive device

[0106] 31 Displacement direction of the first stop element

[0107] 33 Surface of the first stop element

[0108] 35 Control system

[0109] 37 Camera assembly

[0110] 39 Camera

[0111] 41 Partial region of the receiving chamber

[0112] 43 Light source

[0113] 45 Housing of the camera assembly

[0114] 47 Fixed structure of the ultrasonic welding device

[0115] 49 Insertion direction

[0116] 51 Holding assembly

[0117] 53 Illuminant

[0118] 55 Viewing axes of the cameras

[0119] 57 Viewing regions of the cameras

[0120] 59 Openings

[0121] 61 Image evaluation device