The seventh and eighth axes of ABB robots are important devices in industrial robot systems used to expand the working range and flexibility of robots and are widely applied in automated production. The following is a detailed introduction to the applications of the seventh and eighth axes:
1.The application of the seventh axis (external traveling axis)
Linear expansion: The seventh axis is usually a linear guide rail or ground rail, driving the robot to move along a fixed path and expanding its working range.
High-precision positioning: Servo motors and encoders are adopted to achieve high repeat positioning accuracy (within ±0.05mm).
Load capacity: Depending on the model, it can carry the robot body weighing tens to hundreds of kilograms.
Application scenarios:
Welding: In the welding of large workpieces (such as ships and Bridges), the robot moves through the seventh axis to complete the continuous welding of long weld seams.
Spraying: In large-area spraying such as on car bodies and aircraft skins, the robot moves along the seventh axis to achieve uniform spraying.
Material handling and palletizing: In logistics and warehousing scenarios, robots move between multiple workstations via the seventh axis to complete material handling and palletizing.
Machine tool loading and unloading: In the automated production line of CNC machine tools, robots move among multiple machine tools through the seventh axis to achieve automatic loading and unloading of workpieces.
Technical advantage
Improve efficiency: Reduce the time robots spend changing workstations and increase the production rhythm.
Cost reduction: One robot can cover multiple workstations, reducing equipment investment.
Flexibility: The length and layout of the seventh axis can be adjusted according to production requirements to adapt to different workpieces.
2. Application of the eighth axis (external rotation axis)
Functions and Features
Rotational expansion: The eighth axis is usually a rotating platform or positioner, driving the robot or workpiece to rotate and expand its working Angle.
High-precision rotation: Harmonic reducers or RV reducers are adopted to achieve high-precision rotation (within ±0.01°).
Load capacity: Depending on the model, it can carry loads ranging from tens to hundreds of kilograms.
Application scenarios:
Welding: In the welding of circumferential welds (such as pipes and pressure vessels), the robot achieves 360° seamless welding through the rotation of the eighth axis.
Spraying: In the spraying of rotating workpieces (such as wheels and valves), the robot achieves uniform spraying through the rotation of the eighth axis.
Assembly: In the assembly of complex workpieces (such as engines and gearboxes), the robot adjusts the posture of the workpiece by rotating the eighth axis to facilitate assembly.
Improve accuracy: Reduce the error of robot repetitive positioning and enhance processing accuracy.
Reduce costs: Decrease the number of robots and lower equipment investment.
3. The collaborative application of the seventh and eighth axes
Compound motion
Welding application: The robot moves to different positions of the workpiece through the seventh axis and rotates through the eighth axis to complete the welding of complex weld seams.
Spraying application: The robot moves to different areas of the workpiece through the seventh axis and rotates through the eighth axis simultaneously to achieve all-round spraying.
Improve efficiency
Reduce downtime: Robots do not need to move frequently to different workstations, reducing waiting time.
Enhance flexibility: The motion parameters of the seventh and eighth axes can be flexibly adjusted according to production requirements.
Typical case
Automobile manufacturing: In the body welding production line, robots move to different workstations through the seventh axis and rotate through the eighth axis to complete the welding of various parts of the body.
Aerospace: In aircraft skin spraying, the robot moves to different areas of the skin through the seventh axis and rotates through the eighth axis to achieve uniform spraying.
4. Application Precautions
Selection and Configuration
According to the size, weight and process requirements of the workpiece, select the appropriate seventh and eighth axis models.
Ensure that the load capacity, accuracy and speed of the seventh and eighth axes meet the production requirements.
Installation and Commissioning
The installation of the seventh and eighth axes must ensure levelness and verticality to avoid affecting the accuracy.
Zero-point calibration and motion testing should be carried out during debugging to ensure smooth operation.
Maintenance and upkeep
Regularly inspect the guide rails, gears, motors and other components of the seventh and eighth axes to ensure their normal operation.
Regular lubrication and cleaning can extend the service life of the equipment.