Views:5 Author:Cora Publish Time: 2021-02-20 Origin:fiber laser cutting machine
In the initial application of laser cutting, focusing mainly relied on manual. But with the continuous development of laser technology, manual focusing will eventually be eliminated and replaced by automatic focusing.
For example, a high-power laser cutting machine has an efficient and fully automatic focusing function. However, some people will say that the optical path is integrated in the cutting head, can't we simply change the height of the cutting head? When the cutting head rises, the focus position is high, and when the cutting head goes down, the focus position is low. However, it turns out that this is not as simple as everyone thought.
There is a nozzle at the bottom of the cutting head. During the cutting process, the distance between the nozzle and the workpiece (nozzle height) is about 0.5-1.5 mm, which can be regarded as a fixed value, so it is impossible to adjust the focus by lifting the laser head.
The focal length of the focusing lens is constant, so it is unrealistic to adjust the focus by changing the focal length.
Changing the position of the focus lens will change the focus position accordingly: if the focus lens goes down, the focus point will go down; if the focus lens goes up, the focus point will go up. This is indeed a focusing method. A motor is used to drive the focusing lens to move up and down to achieve automatic focusing.
Another method of automatic focusing is to place a variable curvature mirror (or adjustable mirror) before the beam enters the focusing mirror, and change the divergence angle and focus position of the reflected beam by changing the curvature of the mirror.
With automatic focusing function, when processing workpieces of different materials and different thicknesses, the machine can automatically and quickly adjust the focus to a suitable position through numerical control. Therefore, the processing efficiency of the laser cutting machine can be significantly improved, and the perforation time of the thick plate can be greatly reduced.
Therefore, the automatic focusing function is an indispensable and important function of laser cutting machine tools.