Welding Robot Improve Work Efficiency
Welding robots mainly include robots and welding equipment in two parts. The robot consists of a robot body and control cabinet (hardware and software). The welding equipment, arc welding and spot welding, for example, by the welding power supply (including its control system), wire feeder (arc welding), torch (clamp) and other components. For intelligent robots there should also be sensing systems, such as laser or camera sensors and their control devices.
Welding robots produced in various countries in the world are basically joint robots, and most of them have 6 axes. Among them, 1,2,3-axis tools can be sent to the end of the space to different locations, and 4,5,6-axis tool to solve the different requirements of the attitude. The mechanical structure of welding robot body mainly has two forms: one is a parallelogram structure, one is a side-mounted (tilting) structure. The main advantage of the side-mounted (pendulum) structure is that the upper and lower arms have a wide range of motion, allowing the robot's working space to reach almost one sphere. Therefore, this robot can be upside down in the rack to save floor space and facilitate the flow of ground objects. However, this side-mounted robot, 2,3 axis cantilever structure, reducing the rigidity of the robot, generally suitable for smaller robots, for arc welding, cutting or spraying. Parallelogram robot whose upper arm is driven by a pull rod. Lever and the lower arm form a parallelogram of the two sides. It is named. Early development of the parallelogram robot working space is relatively small (confined to the front of the robot), difficult to upside down work. However, the new type of parallelogram robot (parallel robot) developed since the late 1980s has gained universal attention because it has been able to expand the working space to the top, back and bottom of the robot without the rigidity problem of the robot. This structure is not only suitable for lightweight but also for heavy robots. In recent years, spot welding robots (load 100 ~ 150kg) mostly use parallelogram structure of the robot.
Both axes of the above two robots make rotary motion, so servo motors are driven by RV reducer (1 ~ 3 axes) and harmonic reducer (1 ~ 6 axes). Before the mid-1980s, DC servo motors were used for electrically driven robots. Since the late 1980s, all countries switched to AC servo motors. As the AC motor brushless, good dynamic characteristics, the new robot not only the accident rate is low, but also greatly increased maintenance-free time, plus (minus) faster. Some new light robots with loads less than 16kg can reach a maximum moving speed of more than 3m / s at tool center point (TCP) with accurate positioning and small vibration. At the same time, the robot's control cabinet also use 32-bit microcomputer and the new algorithm, so that it has the function of optimizing the path, the trajectory closer to teach the trajectory.
Spot welding welding robot requirements are not very high. Because spot welding just point control, as for the welding clamp in the movement path between points and points is not strictly required, which is the first robot can only be used for spot welding reasons. Spot welding robots should not only have sufficient load capacity, but also in the shift point and the point of speed to move faster, action should be smooth, accurate positioning to reduce the shift time, mention
High work efficiency. The amount of load capacity a spot welding robot needs depends on the type of welder used. For welding tongs separated from transformers, robots 30 to 45 kg are sufficient. However, this kind of welding tongs is not conducive to robots welding the welding tongs into the interior of the workpiece because of the length of the secondary cable on the one hand and the large power loss, on the other hand, the cable runs with the movement of the robot and the cable is damaged rapidly . Therefore, the increasing use of integrated welding tongs. This welding clamp together with the transformer quality is about 70kg. Taking into account the robot to have sufficient load capacity, can be a greater acceleration welding clamp sent to the space for welding, are generally used 100 ~ 150kg load of heavy robots. In order to meet the continuous welding spot welding short-distance rapid displacement requirements. The new heavy-duty robot adds the ability to perform 50mm displacement in 0.3s. This motor performance, computing speed and algorithms have put forward higher requirements.