Precautions for maintenance of ultrasonic plastic welding machine

Ultrasonic plastic welding machineIt is inevitable that there will be malfunctions during use. At this time, we need to repair them. What are the precautions for repairs?

1. From outside to inside
Perform obvious maintenance history, ultrasonic welding conditions, ultrasonic mold temperature, service life and other inspections of the ultrasonic welding equipment that needs to be repaired, and then inspect the machine. Before disassembly, the surrounding failure factors should be queued up, and the internal failure can be determined before disassembly. Otherwise, blind disassembly may cause more and more damage to the equipment.
2. Use your brain before you do it
For a faulty ultrasonic welder, do not start it in a hurry, first ask about the process before and after the fault and the fault phenomenon. For unfamiliar ultrasonic welding machines, you should also be familiar with circuit principles and structural features, and follow the corresponding rules. Before disassembling, you should be fully familiar with the function, location, connection mode of each electrical component and the relationship with other surrounding components. In the absence of an assembly drawing, draw a sketch and mark when disassembling.
3. Mechanical first, electrical
Eliminate the ultrasonic mold problem first, and then conduct electrical inspections. When checking the circuit failure, the detector should be used to find the fault location. After confirming that there is no bad contact fault, check the operation relationship between the circuit and the machine in a targeted manner. Maintain the ultrasonic welding machine to avoid misjudgment.
4. Static before moving
When the equipment is not powered on, judge the quality of the buttons, contactors, relays, and fuses of the electrical equipment to judge the fault. Power-on test, listen to its sound, touch, measure parameters, judge the fault, and then repair it.
5. Clean first and then repair
For severely polluted electrical equipment, clean the buttons, wiring points and contact points first, and check whether the external control key fails. Many failures are caused by dirt and conductive dust. Once cleaned up, the fault is often eliminated.
6. First power amplifier board and then equipment
The failure rate of the power amplification part of the ultrasonic welding machine occupies a high proportion in the entire ultrasonic equipment, so the power amplification part of the ultrasonic generator can often be repaired with half the effort.
7. First general and then special
Generally speaking, due to quality problems in assembly parts or manufacturing processes, ultrasonic repair accounts for about 50% of common faults. Most of the faults of ultrasonic equipment are hard faults, and the faults should be carefully and clearly checked and eliminated before the experiment.
8. Peripheral first and then internal
Don't rush to replace the damaged electrical components, and consider replacing the damaged electrical components after confirming that the peripheral equipment circuit is normal.
9. Repair the fault first and then debug
In some cases, all damaged parts have been replaced, but they are still abnormal, so we need to check the debugging of the protection system. Such as high-current protection, high-frequency protection, and ultrasonic maintenance orders, provided that the FM inductor is in the proper position. If it deviates too far from the normal position, the power amplifier board may be damaged during the debugging process. Note that the 20kHz inductance US line is about 1.1mh, the Taiwan line is about 0.8mh, and the 15KHz Taiwan line is about 1.50mh. Before debugging, be sure to rotate the inductor to the normal position.
10. DC before AC
In the maintenance process, first check the DC voltage, and then check the dynamic operating point of the AC circuit. If it is the problem of the filter circuit, it will cause system problems of the whole machine. The DC power supply of the ultrasonic welding machine is generally 300V, or +-160V local voltage.