In recent years, the role of laser cutting machines in the development of the sheet metal industry has become increasingly prominent. During the cutting process, there are six practical functions. With these practical functions, the processing efficiency and cutting performance of the laser cutting machine can be greatly improved.If you learn the functions of laser cutting and processing, you can save $10,000 a year.
Function 1: Leapfrog
Leapfrog is the empty stroke method of laser cutting machine. As shown in the figure below, after hole 1 is cut, hole 2 needs to be cut next. The cutting head is to move from point A to point B. Of course, the laser should be turned off during the movement. During the movement process from point A to point B, the machine runs “empty”, which is called empty travel.
The empty travel of the early laser cutting machine is shown in the figure below, and the cutting head has to complete three actions in sequence: rising (to a safe enough height), translation (reaching above point B), and descending.
Compress idle time to improve machine efficiency. If the three actions completed sequentially are completed “simultaneously”, the idle time can be shortened: when the cutting head moves from point A to point B, it rises at the same time; when it approaches point B, it descends at the same time. As shown below.
The track of the cutting head moving in the empty space is like an arc drawn by a frog jumping.
In the development of laser cutting machines, leapfrog can be regarded as an outstanding technological progress. Leapfrog action only takes up the translational time from point A to point B, saving the time for rising and falling. When the frog jumps, it catches the food; when the laser cutting machine jumps, what it “catches” is high efficiency. If the laser cutting machine does not have the leapfrog function, I am afraid it will not be popular.
Function 2: Auto focus
When cutting different materials, the focus of the laser beam is required to fall on different positions of the cross-section of the workpiece. Therefore, it is necessary to adjust the position of the focal point (focusing). Early laser cutting machines generally used manual focusing; at present, many manufacturers’ machines have realized automatic focusing.
Some people may say that it is enough to change the height of the cutting head. When the cutting head is raised, the focus position will be higher, and if the cutting head is lowered, the focus position will be lower. It’s not that simple.
In fact, during the cutting process, the distance between the nozzle and the workpiece (nozzle height) is about 0.5-1.5mm, which may be regarded as a fixed value, that is, the nozzle height remains unchanged, so the focus cannot be adjusted by lifting the cutting head (otherwise cannot complete the cutting process).
The focal length of the focusing mirror cannot be changed, so it cannot be expected to adjust the focus by changing the focal length. If the position of the focusing mirror is changed, the focus position can be changed: when the focusing mirror is lowered, the focus is lowered, and when the focusing mirror is raised, the focus is raised. ——This is indeed a way of focusing. Using a motor to drive the focusing mirror to move up and down can realize automatic focusing.
Another automatic focusing method is: before the light beam enters the focusing mirror, install a variable curvature mirror (or adjustable mirror), and change the divergence angle of the reflected beam by changing the curvature of the mirror, thereby changing the focus position. As shown below.
With the automatic focusing function, the processing efficiency of the laser cutting machine can be significantly improved: the time for piercing thick plates is greatly reduced; when processing workpieces of different materials and thicknesses, the machine can automatically and quickly adjust the focus to the most suitable position.
Function 3: Automatic edge detection
When the sheet is placed on the table, if it is skewed, it may cause waste when cutting. If the inclination angle and origin of the sheet can be sensed, the cutting process can be adjusted to suit the angle and position of the sheet, thereby avoiding waste. The automatic edge finding function came into being.
After starting the automatic edge finding function, the cutting head starts from point P, and automatically measures 3 points on the two vertical sides of the sheet: P1, P2, P3, and automatically calculates the inclination angle A of the sheet, and the angle of the sheet. origin.
Function 4: Pre-punched
Pre-punched is a processing technology, not a function of the machine itself. When laser cutting thicker plates, the cutting process of each contour has to go through two stages: 1. Perforation, 2. Cutting.
Pre-punched avoids overburning.During the piercing process of the thick plate, heat accumulation is formed around the piercing point, and if it is cut immediately, overburning will occur. Using the concentrated piercing process, when all the piercings are completed and the cutting is returned to the starting point, there is sufficient time for heat dissipation to avoid overburning.
Function 5: Micro-connection
During laser cutting, the sheet is held by serrated support bars. If the cut part is not small enough to fall from the gap of the support bar; if it is not big enough to be held by the support bar, it may lose its balance and warp. The cutting head moving at high speed may collide with it, which may cause the machine to stop at least, or damage the cutting head at worst.
This phenomenon can be avoided by using the bridge (micro-connection) cutting process. When programming graphics for laser cutting, the closed contour is intentionally broken at several places, so that the parts will stick to the surrounding materials after cutting and will not fall off. These broken places are the bridge positions. Also known as a breakpoint, or a micro-joint (this name comes from a blunt translation of MicroJoint). The breaking distance is about 0.2-1mm, which is inversely proportional to the thickness of the sheet. Based on different angles, there are these different names: based on the outline, it is disconnected, so it is called a breakpoint; based on the part, it is bonded to the base material, so it is called a bridge or micro-connection.
Function 6: Common edge cutting
If the contours of adjacent parts are straight lines with the same angle, they can be merged into a straight line and cut only once. This is known as coedge cutting. Obviously, common edge cutting reduces the cutting length and can significantly improve processing efficiency.
Coedge cutting does not require the shape of the part to be rectangular. As shown below.
The blue line is the common side, and the common side cutting not only saves cutting time, but also reduces the number of perforations, so the benefits are very obvious.
