Daily setting and maintenance of injection molding machine manipulator

2021-06-23  1327

The reason for the failure of the automatic manipulator is that the joints of the manipulator are mostly fixed by screws, and the screws may become loose due to long-time vibration; And the formation of the manipulator frame, parts of the joint block fracture. On the other hand, the vibration of the manipulator is caused by the loosening of the wire joint and the relay, resulting in the poor contact of the electric circuit. Lead to manipulator disorderly action, electric control crash, burn out electric control and so on.

Precautions for daily protection tasks:

1. Oil pressure buffer: it should be changed on schedule.

2. The long used cylinder head seals, reflecting pipes and joints should be replaced in time.

3. 12 months on schedule to review and rectify the wire connector, plug, socket, etc.

4. Pneumatic components: simple, multi-functional manipulator of all initiatives rely on the gas source to promote, the gas source must remain unchanged, small wavering, no water.

Because gas and water are two different media, gas is invisible, water is visible, water in the gas pipe, cylinder, electromagnetic retention will occur scale, the formation of electromagnetic valve stuck, gas channeling, gas seal wear leakage, cylinder leakage, leakage and other scenes, the cylinder action appears powerless, creeping, no action or sudden quick action, gas pipe, joint burst and other scenes.

To sum up, the automatic manipulator can effectively replace the manual, improve the production efficiency of the enterprise, and the maintenance cost is low, but in the daily maintenance also need to be carefully maintained. So as to avoid the failure of automatic manipulator and the impact on the production efficiency of the enterprise.

For operators, the daily maintenance of manipulator is very important. Next, let's introduce some precautions:

1. Guide rails and bearings

Guide rails and bearings at all shafts should be kept clean and well lubricated. If the manipulator is running in a dusty environment, the guide rail needs to be cleaned frequently. If you find any metal debris or powder, it may indicate poor lubrication. In order to ensure proper lubrication, it is very important to have proper linear guidance system. Most manipulators have automatic lubrication system and parts that need to be replaced regularly.

2. Cycle time of manipulator

One of the key points to keep the manipulator in good operation is simple observation and listening, which can reveal a lot of information about the overall operation of the manipulator. The manipulator works through specific actions, so it listens to any abnormal sound, such as whistling, clicking, etc., which indicates that the bearing cannot rotate normally or some other component is stuck. The link part of the manipulator moves along the guide rail with power cable and vacuum hose, which will make a normal click sound, but the sound is smooth and stable. Check any observable bearings to make sure they rotate smoothly. Just checking and listening to some signs of wear or need to be adjusted can greatly help to maintain the optimal operation of the manipulator.

3. Drive system

If the manipulator is driven by assembly frame transmission gear, pay attention to whether there is any hesitation or shaking during operation. All movements except smooth and smooth motion can indicate that the drive system is damaged or some foreign matters are deposited inside. When the manipulator moves downward, the method to quickly check the movement or backlash between the assembly beam and the transmission gear is to push and pull the moving arm, and feel abnormal movement (different movements back and forth).

However, due to the high tolerance accuracy of normal manufacturers, this test method will be very inaccurate. If you suspect that there may be a problem with the assembly beam and drive gear, a better way is to use a long range magnetic base. After adjusting the backlash according to the manufacturer's instructions, check the whole stroke of the shaft to ensure that there is no too tight place between the assembly beam and the transmission gear. If the backlash cannot be adjusted, the mounting frame and transmission gear may be worn and need to be replaced. If it is necessary to repair the assembly frame and transmission gear, it is better to replace both components at the same time to ensure long-term performance.

As for the shaft driven by the conveyor belt, pay close attention to the wear of the conveyor belt, the falling debris and the damage itself. Check the pulley carefully for signs of dust from the belt material. Make sure that the belt and drive pulleys and sheaves are fully aligned. Belts that deviate from the direction will wear away very quickly. As long as it is a belt driven system, the preload of the belt itself can be checked according to the manufacturer's instructions. These specifications will tell you: relative to the pulley, the appropriate amount of error in the specific position of the conveyor belt.

4. Pneumatic system

Including multi axial servo drive, almost all manipulators have pneumatic function as long as there is wrist rotation and vacuum grasping action. Pay close attention to the suction cup of the filter pressure regulating valve unit. The water in it indicates that the humidity of the compressed air source passing through the system is too high. A small amount of water vapor may be transmitted to the pneumatic valve and actuator, causing oxidation and internal pollution, which may eventually cause the pressure regulating valve to stick or the actuator to stick or fail intermittently.

If the suction cup is equipped with an automatic dehumidification system, the contamination or discoloration on the suction cup also indicates that the moisture is increasing before removal. If water accumulates in the suction cup, it can enter the system even for a short time, causing the above problem. If you notice any physical damage to the pneumatic hose, there may be a leak in the system.

If the pneumatic circuit is full of air at normal operating pressure and there is a leak somewhere in the circuit, you should be more likely to detect a significant hissing sound, which will help you locate the leak.

5. Check molding equipment

Standard manipulator is usually installed on the template of molding equipment. When the equipment is running rapidly, the vibration from the forming equipment may be transmitted to the manipulator, which may cause damage. Simply observe the operation of the molding equipment, ensure that the mold movement is adjusted to a reasonable state, reduce the number of shaking or vibration, can extend the life of the manipulator. In the case of high-speed operation, the vibration frequency may be very high. It is better to install the manipulator on the supporting structure independent of the forming equipment.

6. Pay attention to the wear of wiring

When inspecting the face of the mechanical watch, if black particles or powder are found, it indicates that the circuit wiring of the manipulator has signs of wear. However, even if you can't find these wear signals, carefully look at all the power supply, transformer or encoder cables, the inside and outside sides of the wiring path are OK, because during the production cycle, the wiring of the continuous friction manipulator or the wiring connected to the cable guide will eventually wear out and fail. Ensure the safety of wiring ties and the reasonable installation of cables.

7. Check the lubrication

The manipulator uses spring-loaded lubrication rods, which only need to be replaced once a year unless there is evidence of insufficient lubrication of the guide rail. Equipped with automatic lubrication system, it can continuously lubricate along the movement of the manipulator. However, if there are some surfaces on which the manipulator can not move normally, the manual lubrication should be carried out for these areas, or the regular programmed action of automatic system lubrication should be realized. If you find rust, corrosion or wear on any moving surface, or if it's just too dry, they're not lubricated enough. Always refer to the manipulator manual for proper lubrication of metal parts. The assembly beam - traditional gear system is lubricated automatically by a lubricating oil storage unit, but needs to be replaced annually.

8. Vacuum gripper circuit

The vacuum should be near instantaneous, and the appropriate controller input should be equivalent to grabbing the product. If you find that the vacuum is turned on, then the input light source appears, and the delay time is more than 2 seconds, it indicates that there is a vacuum pipeline leakage, defect or improper adjustment of the switching device. It is easy to test through the plug-in main control panel.

If the manipulator is equipped with a digital vacuum switching unit, it can quickly and automatically fine tune the minimum vacuum threshold for grasping the product. The process can be completed when the manipulator runs in automatic mode. The set parameters of each production cycle are stored in the memory, which can save time in the next production change. There are two other advantages of digital vacuum switching device: grabbing threshold signal, electronic filter makes up for the vibration of the product on the vacuum sucker when it moves rapidly. The product release threshold is different from the grab threshold, which can be programmed to ensure the appropriate release under the condition of rapid production cycle.