Vertical detection device and method for laser welding

The invention relates to a vertical detection device for laser welding. The vertical detection device for the laser welding comprises a pneumatic baffle (100), a bidirectional cylinder (200), a laser displacement sensor (300), a fixing plate (400), a connecting plate (500), a connecting part (600) and a welding head (800). The vertical detection device for the laser welding is characterized in that the pneumatic baffle (100), the bidirectional cylinder (200), the laser displacement sensor (300), the fixing plate (400), the connecting plate (500) and the connecting part (600) are integrated with the welding head (800); once the welding head (800) is not vertical to a weld joint (1100) to be welded, a distance signal measured by the laser displacement sensor (300) is converted into a welding head deviation angle signal through a sensor controller, and then the deviation angle signal is sent by an I/O unit to a robot control system for readjustment so as to enable the welding head (800) to be vertical to the weld joint (1100) to be welded. The vertical detection device for the laser welding can be applied to different welding automation platform to effectively solve the problem that the welding head is not vertical to the weld joint during welding a thick plate, and thus the welding quality of the thick plate can be ensured.