Fault analysis of ultrasonic plastic welding machine
1. Ultrasonic mold heating
When the ultrasonic mold is working, there will be some heating phenomenon, which is caused by the mechanical loss of the material itself and the heat conduction of the welding parts. When there is no load (that is, no contact with the workpiece), the ultrasonic wave is continuously emitted for more than half an hour and the temperature cannot exceed 50-70℃. If there is heat, it proves that the welding head is damaged or the material is unqualified and needs to be replaced.
2. Ultrasonic mold whistle
When the ultrasonic mold is working, the following reasons should be analyzed:
(1) installation screw is loose
(2) whether the welding head cracks
(3) welding head and should not contact with the object contact.
3. Ultrasonic generator shows overload
When the generator sets an overload alarm, the following steps should be taken to check:
No load test, if the working current is normal, it may be the ultrasonic mold contact should not contact the object or between the welding head and the welding seat parameter adjustment failure.
When the no-load test is abnormal, it is necessary to first observe whether the welding head is cracked and installed firmly, and then remove the welding head and carry out the no-load test to exclude whether there is a problem with the transducer + amplitude transformer, and eliminate it step by step. After eliminating the possibility of failure of transducer + amplitude transformer, remove and replace the new ultrasonic mold to judge.
Sometimes there will be no load test normal, and can not work normally, it may be the ultrasonic mold and other original changes in the internal sound energy, resulting in poor transmission of sound energy, here is a relatively simple judgment method: hand touch method. When the welding head or amplitude variable rod surface works normally, the amplitude is very uniform, and the hand feels velvety and smooth. When the sound energy transmission is not smooth, the hand feels shaking or shaking feeling, and then the elimination method is adopted to eliminate the problematic parts. When the ultrasonic generator is abnormal, it can also produce the same situation, because normally the input waveform of the transducer should be the smooth sine wave, when the sine wave has a sharp peak or abnormal waveform, it can also produce this phenomenon, then it can be replaced by another whole branch sound energy element to distinguish.
Contact Person: Ms. Hogo Lv