Components and working principles of laser cutting machine

Laser cutting machine consists of laser transmitter, cutting head, beam transmission component, machine tool workbench, CNC system, computer (hardware, software), cooler, protective gas cylinder, dust collector, air dryer and other components.

1. Laser generator A device that generates laser light source. For the purpose of laser cutting, except for a few occasions where YAG solid lasers are used, most of them use CO2 gas lasers with high electro-optical conversion efficiency and high output power. Since laser cutting has very high requirements for beam quality, not all lasers can be used for cutting.

2. The cutting head mainly includes parts such as nozzle, focusing lens and focusing tracking system. The cutting head drive device is used to drive the cutting head to move along the Z axis according to the program. It consists of a servo motor and transmission parts such as screw rods or gears.

(1) Nozzle: There are three main types of nozzles: parallel, convergent and cone.

(2) Focusing lens: To use the energy of the laser beam for cutting, the original beam emitted by the laser must be focused by the lens to form a high energy density spot. Medium and long focus lenses are suitable for thick plate cutting and have low requirements for the spacing stability of the tracking system. Short focus lenses are only suitable for thin plate cutting below D3. Short focus has strict requirements on the spacing stability of the tracking system, but it can greatly reduce the output power requirements of the laser.

(3) Tracking system: The laser cutting machine focusing tracking system is generally composed of a focusing cutting head and a tracking sensor system. The cutting head includes light guide focusing, water cooling, air blowing and mechanical adjustment parts. The sensor is composed of a sensor element and an amplification control part. Depending on the different sensor elements, the tracking system is completely different. Here, there are mainly two forms of tracking systems. One is a capacitive sensor tracking system, also known as a non-contact tracking system. The other is an inductive sensor tracking system, also known as a contact tracking system.

3. External light path of the beam transmission component: a refractive mirror, which is used to guide the laser in the required direction. In order to prevent the beam path from malfunctioning, all mirrors must be protected by a protective cover and a clean positive pressure protective gas is introduced to protect the lens from contamination. A set of good performance lenses will focus a beam with no divergence angle into an infinitely small spot. Generally, a 5.0-inch focal length lens is used. A 7.5-inch lens is only used for materials >12mm thick.

4. Machine tool workbench machine tool host part: the machine tool part of the laser cutting machine, the mechanical part that realizes the movement of the X, Y, and Z axes, including the cutting work platform.

5. CNC system The CNC system controls the machine tool to realize the movement of X, Y, and Z axes, and also controls the output power of the laser.

6. Cooling system Chiller: used to cool the laser generator. The laser is a device that converts electrical energy into light energy. For example, the conversion rate of CO2 gas laser is generally 20%, and the remaining energy is converted into heat. The cooling water takes away the excess heat to keep the laser generator working normally. The chiller also cools the reflector and focusing lens of the machine tool's external optical path to ensure stable beam transmission quality and effectively prevent the lens from deforming or bursting due to excessive temperature.

7. Gas cylinders Gas cylinders include laser cutting machine working medium gas cylinders and auxiliary gas cylinders, which are used to supplement the industrial gas of laser oscillation and supply auxiliary gas for the cutting head.

8. Dust removal system extracts the smoke and dust generated during processing, and filters them to make the exhaust gas emissions meet environmental protection standards.

9. Air cooling dryers and filters are used to supply clean dry air to the laser generator and beam path to keep the path and reflector working normally.

Maven High Precision 6 Axis Robotic Automatic Fiber Laser Welding Machine