Technical difficulties of laser cutting three-dimensional curves

(1) The direction of the laser beam In order to ensure the accuracy of the cutting and the quality of the cut, whether it is in plane cutting or three-dimensional cutting, the direction of the laser beam must always be perpendicular to the object being cut, that is, the laser beam must be kept perpendicular to the object being cut during processing. It is in the normal direction of the curve or perpendicular to the surface of the curve. In two-dimensional cutting, because the curve is in the same plane, the laser beam is always perpendicular to the plane where the curve is located, so this is easy to do. But in three-dimensional cutting, the curve is in different planes, and the direction of the curve is not fixed. Its direction is always changing during the processing. AB is any curve in the space. Make sure that the laser beam is always in the processing. It is perpendicular to the curve, so how to keep the laser beam always perpendicular to the curve being cut is an important problem in solving three-dimensional curve cutting. (2) During the cutting process, the position of the focal point of laser cutting should ensure that the relative position of the focal point and the surface of the part remains unchanged, that is, the distance between the nozzle and the surface of the part is always the same, as shown in Figure 1(b). In two-dimensional cutting, the processing curve to be processed is always processed in a plane, which is well guaranteed. In three-dimensional processing, since the characteristics of the spatial curve are in different curved surfaces, how to make the nozzle center and the surface of the part Keeping the distance constant is another important issue that needs to be solved. (3) Converting the characteristics of the space curve into laser cutting data is different from the two-dimensional curve. The three-dimensional space curve is composed of multiple features in different planes, and there is not much connection between each feature. During the processing It may be necessary to cut in multiple planes one after another. How to reflect the characteristics of the three-dimensional curve easily and quickly and convert it into laser cutting data is the most important problem to be solved by three-dimensional laser cutting. This is also the most complicated step in the practical application of 3D laser cutting technology.