Problems encountered in laser precision machining

1 The laser cutting accuracy is not good The laser power adjustment is mostly controlled by the frequency + duty ratio method, so the displacement control needs real-time and precise conversion, different speeds have different power, but will be generated when the graphics are cut. Different speeds. When the speed drops sharply and the laser power is too late to change, over-exposure occurs.

2 The trajectory of the trajectory is not easy to reach under the high precision. The accuracy of the path needs to be emphasized in the movement of the cutting system. Therefore, the control of the motor needs to be very good so that the cutting pattern will not be deformed, as shown in Fig. 3 and Fig. 4; If the open-loop (pulse, stepping) method is used, the follow-up degree cannot be corrected in real time; if it is required to achieve high precision, only the closed loop (speed, torque) control can be used to meet the requirement. However, closed-loop control requires PID adjustment to have better follow-up effect. However, PID tuning often takes a long time and is quite time-consuming.

3 The laser power is not easy to adjust At present, most of the objects to be cut are multi-layer materials (solar panels, mobile phone touch film), and need to use different power for cutting; however, laser adjustment (VAOTable) is only available on the market for laser dedicated controllers. One group, it is not easy to switch and adjust the cutting power, so that only the cutting path can be repetitively cut on the material layer to meet the required requirements. However, this will cause the production speed to fail to increase.

4 The speed planning of the next day is time-consuming. Due to the complexity of laser processing graphics, simple speed planning can no longer meet the processing and cutting results. For example, mobile phone touch die cutting uses Spline curves or longer geometric lines and arcs in most cases. If you cannot do speed control accurately, it will cause the mechanism to accelerate and decelerate and shake or the figure is seriously deformed (such as overcut and jitter), as shown in Figure 5. Because most of the designers of the platform only provide position graphs and do not have data for speed planning, the speed needs to be planned manually. On the one hand, the design process takes a long time and it is necessary to re-correct it in the event of a planning error. It will also result in an increase in production capacity.