In recent years, the role of laser cutting machine in the development of sheet metal industry has become increasingly prominent. In the cutting process, there are six practical functions, which can greatly improve the processing efficiency and cutting performance of the laser cutting machine.

1. Leapfrog

Leap frog is an empty way of laser cutting machine. As shown in the figure below, after cutting hole 1, cut hole 2. The cutting head shall be moved from point A to point B. Of course, the laser must be turned off during the movement. The movement process from point A to point B, where the machine runs "empty", is called empty distance.

The idle travel of the early laser cutting machine is shown in the figure below. The cutting head needs to complete three actions successively: rising (to a safe enough height), translation (reaching above point B), and descending.

Compressing the idle time can improve the efficiency of the machine. If the three actions completed successively are changed to "simultaneous" completion, the idle travel time can be shortened: when the cutting head moves from point A to point B, it rises at the same time; When approaching point B, descend at the same time. As shown in the figure below.

The path of the empty motion of the cutting head is like an arc drawn by a frog jumping.

In the development process of laser cutting machine, leapfrog is an outstanding technological progress. Leapfrog only takes up the translation time from point A to point B, saving the time for rising and falling. The frog jumped and caught the food; The leapfrog of laser cutting machine "captures" high efficiency. If the laser cutter does not have this function now, I'm afraid it will not enter the stream.

2. Auto focus

When cutting different materials, the focus of the laser beam is required to be at different positions of the work-piece section. Therefore, it is necessary to adjust the focus position (focusing). The early laser cutting machine generally adopts manual focusing mode. At present, many manufacturers' machines have realized automatic focusing.

It may be said that it is better to change the height of the cutting head. When the cutting head is raised, the focus position will be higher, and when the cutting head is lowered, the focus position will be lower. Actually not. In the actual cutting process, the distance between the nozzle and the work-piece (nozzle height) is about 0.5~1.5mm, which can be regarded as a fixed value, that is, the nozzle height remains unchanged, so the focus cannot be adjusted by lifting and lowering the cutting head.

The focal length of the focusing mirror is unchangeable, so it can not be expected to focus by changing the focal length. If you change the position of the focusing mirror, you can change the focus position: if the focusing mirror drops, the focus drops, and if the focusing mirror rises, the focus rises—— This is really a way of focusing. Auto focusing can be realized by using a motor to drive the focusing mirror to move up and down.

Another automatic focusing method is to set a variable curvature mirror (or adjustable mirror) before the beam enters the focusing mirror, and change the divergence angle of the reflected beam by changing the curvature of the mirror, thus changing the focus position. With the auto focusing function, the processing efficiency of the laser cutter can be significantly improved: the thick plate perforation time is greatly reduced; When processing work-pieces of different materials and thicknesses, the machine can automatically quickly adjust the focus to the most appropriate position.

3.  Automatic tracing-edge

When the sheet is placed on the workbench, if it is skewed, it may cause waste during cutting. If the inclination angle and origin of the sheet can be sensed, the cutting processing program can be adjusted to suit the angle and position of the sheet, so as to avoid waste. Therefore, the automatic tracing-edge function came into being.

After starting the automatic tracing-edge function, the cutting head starts from point P, automatically measures three points on the two vertical edges of the sheet: P1, P2, P3, and automatically calculates the inclination angle A of the sheet and the origin of the sheet. This function can save the time of adjusting the work-piece first - it is not easy to adjust (move) work-pieces weighing hundreds of kilograms on the cutting workbench, which improves the efficiency of the machine.

4. Centralized perforation

Centralized piercing, also known as pre piercing, is a processing process, not a function of the machine itself. When laser cutting thick plates, the cutting process of each contour will go through two stages: 1. piercing and 2. cutting.

The process flow of the conventional processing technology is: A point piercing → cutting contour 1 → B point piercing → cutting contour 2 →… The so-called centralized perforation refers to the centralized execution of all perforation processes on the whole board in advance, and then the cutting process is executed later. Compared with the conventional processing technology, the total length of the machine's running track is increased during centralized piercing. Then why should we use concentrated perforation?

Because centralized perforation can avoid over burning. In the process of thick plate perforation, heat accumulation is formed around the perforation point. If the cutting is followed closely, over-burning will occur. The centralized piercing process is adopted. When all perforations are completed and the starting point is returned for re cutting, due to sufficient time for heat dissipation, the over burning phenomenon is avoided.

Concentrated piercing can improve processing efficiency. At present, there are still many laser cutting machines that do not have the function of automatic focusing. The process parameters of thick plate processing, piercing and cutting are different. The nozzle height during piercing shall be higher than that during cutting. If the conventional processing technology is adopted, in order to ensure the cutting quality and efficiency, the focus of the laser beam can only be manually adjusted to the optimal position according to the cutting needs. Imagine this: at the beginning, manually set the focus to the required position for piercing; Then, turn the focus to the desired position for cutting; Adjust to the perforation position again, and perforate; Until the processing is completed - this is a nightmare. Therefore, the focus of perforation must not be in the optimal position, and the perforation time will be longer. However, if centralized piercing is adopted, the focus can be adjusted to the position suitable for piercing. After the completion of piercing, the machine will be paused, and then the focus position will be adjusted to the optimal position required for cutting; In this way, the perforation time can be shortened by more than half, greatly improving the efficiency. Of course, if necessary, other process parameters can be adjusted or changed in the middle of centralized piercing and cutting. We generally call the driving focus lens auto zoom F-axis; If manual zoom is used for centralized perforation and cutting, can it be called "H" (Hand) axis "zoom"?

Concentrated piercing also carries risks. If a collision occurs during the cutting process, resulting in the change of the plate position, the part that has not been cut may be scrapped. Centralized piercing process needs the help of automatic programming system.

5. Bridge position/Micro joint

During laser cutting, the sheet metal is held by the serrated support strip. If the cut part is not small enough, it cannot fall from the gap of the support strip; If it is not big enough, it cannot be supported by the support strip; It may lose balance and tilt. The cutting head moving at high speed may collide with it, which may cause shutdown or damage to the cutting head.

This phenomenon can be avoided by using micro joint cutting technology. When programming the laser cutting of graphics, the closed contour is intentionally disconnected in several places to make the parts stick to the surrounding materials after the cutting is completed without falling. These disconnection places are bridge positions. It is also called breakpoint, or micro connection (this is called from the hard translation of MicroJoint). The distance of disconnection, about 0.2~1mm, is inversely proportional to the thickness of the sheet. Based on different angles, we have these different names: based on the contour, broken, so called breakpoint; Based on the part, it is adhered to the base metal, so it is called bridge position or micro connection.

The bridge position connects the parts with the surrounding materials. The mature programming software can automatically add a suitable number of bridge positions according to the length of the contour. It can also distinguish the internal and external contours, and decide whether to add bridge positions, so that the internal contour (waste) without bridge positions will fall, while the external contour (parts) of bridge positions will stick to the base metal without falling, thus eliminating the sorting work.

6. Common edge cutting

If the contour of adjacent parts is a straight line with the same angle, they can be combined into a straight line and cut only once. This is called co edge cutting. Obviously, co edge cutting reduces the cutting length and can significantly improve the processing efficiency. Common edge cutting does not require the shape of the part to be rectangular. See the figure below.

The sky blue line is a common edge, cutting at the same edge, which not only saves cutting time, but also reduces the number of perforations. Therefore, the benefits are very obvious. If 1.5 hours are saved every day due to common edge cutting, about 500 hours are saved every year, and the comprehensive cost per hour is calculated as 100 yuan, it is equivalent to creating an additional benefit of 50000 yuan per year. Common edge cutting depends on intelligent automatic programming software.

About HGTECH: HGTECH is the pioneer and leader of laser industrial application in China, and the authoritative provider of global laser processing solutions. We have comprehensively arranged laser intelligent equipment, measurement and automation production lines, and smart factory construction to provide overall solutions for intelligent manufacturing.