What Is a Galvo Laser Welding System?

Introduction to Galvo Laser Welding Systems

The galvo laser welding machine replaces the traditional worktable with high-speed moving scanning mirrors, using specialized software with powerful graphic processing capabilities to achieve program-controlled instantaneous multi-point welding. This effectively improves production efficiency and flexibility. 

The welder employs a dynamic welding process involving a set of scanning mirrors, with the movement of the scanning mirrors substituting for the movement of the workpiece or welding optical assembly. This allows the galvo mirrors to rapidly switch the laser beam between welding points within the scanning lens, offering significant advantages when the distance between welding points is large or when the workpiece contains numerous welding points.

The galvo laser welding system, also known as a galvo laser welder, mainly consists of a chiller, a laser source, a robotic arm (gantry), and a galvanometer head. It also includes some basic control systems. The most critical component of the galvo laser welding system, and what sets it apart from traditional collimated welding, is the galvanometer head. 

This system boasts fast welding speeds, high precision, stable quality, ease of operation, and simple maintenance, making it particularly suitable for precision point welding of various parts. Its production efficiency is about eight times that of conventional laser spot welding machines. 

The use of the galvo for rapid scanning and deflection of the laser boosts welding productivity. When combined with the movement of a robotic arm, it can achieve flying welding and marking, thereby increasing laser accessibility. This is similar to the deflection and scanning functions of electromagnetic coils in electron beam welding.

The Welding Head of the Galvo Laser Welding System

Much like laser marking, the main difference between this and traditional laser welding is the method of laser beam positioning. 

The galvo, also known as a galvanometer scanner, is based on the design principles of an ammeter. Here, mirrors replace the needle, and the probe signal is replaced by -5V to 5V or -10V to +10V DC signals controlled by a computer to perform the desired actions. 

The laser beam, in pulsed or continuous mode, is directed onto two mirrors in the scanning galvo, which can scan along the X and Y axes. The computer controls the reflection angles of these mirrors to achieve arbitrary deflection of the laser beam, focusing the laser spot with a certain power density onto different positions on the workpiece surface to perform welding. 

Based on the laser focusing method, laser scanning welding of the galvo company can be divided into dynamic focusing (focused before the beam enters the galvo) and f-θ lens focusing (focused after the beam exits the galvo). Usually, a dynamic focusing module comprises a movable negative lens and a focusing lens. The movable negative lens is mounted on the Z-axis servo motor's shaft, and the Z-axis servo motor finely adjusts the distance between the negative lens and the focusing lens to ensure the beam's focal spot on the workpiece remains consistent within a certain range.