Many machine manufacturers now choose to use injection […]
Many machine manufacturers now choose to use injection molding machine manipulators as the main production method, but the use of automated robots in production can improve the production efficiency and product quality of the products as well as reduce the production cost of the products, and injection molding in production. Whether the machine manipulator can work accurately is actually a three-dimensional space positioning problem, which is a combination of several line quantity and angular quantity positioning. In many simpler cases, a single magnitude may be dominant. The factors that affect the positioning error of a single line or angular amount are as follows:
1. Positioning method - Different positioning methods have different influencing factors. When the mechanical stop is positioned, the positioning accuracy is related to the stiffness of the block and the speed at which the block is abutted.
2. Positioning speed - The positioning speed has a great influence on the positioning accuracy. This is because the energy of the moving parts that must be dissipated differs when the positioning speed is different. Generally, in order to reduce the positioning error, the positioning speed should be reasonably controlled, such as improving the cushioning performance and the buffering efficiency of the buffer device, and controlling the driving system to slow down the moving parts in time.
3. Accuracy - The manufacturing precision of the manipulator and the accuracy of the installation speed have a direct impact on the positioning accuracy.
4. Stiffness——When the structural rigidity and contact stiffness of the manipulator itself are low, the positioning accuracy is generally low due to the easy vibration.
5. Weight of the moving part - The weight of the moving part includes the weight of the robot itself and the weight of the object to be grasped. The change in the weight of the moving parts has a great influence on the positioning accuracy. Generally, when the weight of the moving member is increased, the positioning accuracy is lowered. Therefore, it is not only necessary to reduce the weight of the moving parts themselves, but also to consider the influence of the change in the weight during work.
6. Drive source - hydraulic and pneumatic pressure fluctuations and voltage, oil temperature, temperature fluctuations will affect the repeatability of the robot. Therefore, the necessary voltage regulation and oil temperature adjustment measures are adopted. If the accumulator is used to stabilize the oil pressure, the heater or cooler is used to control the oil temperature. At low speed, the temperature and pressure compensated flow control valve are used for control.
7. Control system—The position control accuracy of switch control, electro-hydraulic proportional control and servo control is different. This is not only due to the different accuracy and sensitivity of the various control elements, but also to the presence or absence of position feedback devices.