With the continuous improvement of the quality of lead-acid batteries , its application range is more and more extensive. To produce a qualified lead-acid battery, it must go through multiple production processes, and each production process has strict process requirements. At present, most battery shell manufacturers only manually test the injection molding effect after the injection molding of the battery shell to eliminate the non-conforming products. However, due to factors such as temperature and material during the injection molding process of the shell shell, the shell may have defects such as pores and bristles, because the cells of the small-shell lead-acid battery are connected to each other in a single cell. The spacing between the individual cells of the thin and small dense batteries is also small, so it is difficult to find some defects of the pool shell by manual inspection. When the semi-finished battery is removed, the defective products caused by the detection instruments are removed. Late, a lot of manpower and material resources have been wasted.

In view of this situation, we have successfully developed a high-quality and inexpensive pool-shell inspection machine with reference to the high-voltage detection principle in foreign related battery cell adhesion detection equipment. It is suitable for the detection of all kinds of large, medium and small dense lead-acid battery pool shells, especially for small-density lead-acid batteries.

2, detection principle

Two thick copper plates are placed on the two sides of the separator of the battery cell shell after injection molding, one copper plate is connected to DC high voltage, the other copper plate is grounded, and 15,000 volts to 30,000 VDC is added between the two copper plates. High voltage, by detecting the magnitude of the leakage current to judge whether the pool shell is good or bad, when the shell partition has pores or hairy defects, the partition is thinner, the ability to withstand high pressure is poor, the air ionization is serious, and the leakage current is normal. The pool shell is significantly increased. When the detected leakage current is greater than the set leakage current, we use an audible and visual alarm to indicate that the battery is unqualified. (The set leakage current value is determined according to the actual situation). Take a 12V 6 single cell small dense lead-acid battery as an example

3, the composition of the main circuit

The key to the detection of the battery case by the shell detector is the generation of DC high voltage.

In the figure, TM1 is a voltage regulator, TM2 is a high voltage transformer, and the high voltage generated by TM2 is rectified by a high voltage diode D1 to obtain a DC high voltage of 0 to 30,000 volts (peak voltage). The high-voltage resistors R1 and R2 are current limiting resistors. We indirectly indicate the actual high voltage value by the voltmeter V. That is, the low voltage of the high voltage transformer TM1 is sent to the voltmeter. The voltage value indicated on the meter head is based on the high voltage transformer. The high pressure value after the conversion of the secondary relationship. This treatment saves both cost and safety. The device sends the P21 voltage to another comparison link. This voltage is compared with the set leakage current to control whether the sound and light alarm is used to eliminate the non-conforming product. Since the material of the battery case is slightly different, the humidity of the air also changes. Various factors may cause a slight change in the voltage of the P21 point in the case of a qualified battery case, and this change is enough to cause the device to misjudge. In order to solve this problem, we have inserted different resistors (dashed box) in the main loop, and adjust the knob SA to make a choice to offset various effects and avoid misjudgment of the device.

4, DC high voltage insulation, high voltage and high voltage safety of components and other issues

The principle of DC high voltage generation is not complicated. The key to this equipment lies in other aspects.

The first is the high voltage insulation problem. If the high-voltage insulation is not handled well, it will not only affect the normal operation of the equipment, but also have great hidden dangers to the personal safety. Followed by the high voltage resistance of components, if the selection of components does not meet the requirements, the equipment will not meet the user requirements for long-term work. In addition, because of the danger of high pressure on people, we should pay special attention to the safe handling of high pressure. We have done a lot of detailed work around the above issues. We have fully sealed the high-voltage transformer with vacuum epoxy resin, and carried out strict high-voltage insulation test on the high-voltage transformer. Although the rated current of the main circuit is small, the rated withstand voltage is 1.5 to 2 times of the actual high voltage. Therefore, all the high-voltage wires are made of high-voltage wires with a rated withstand voltage of 1.5 to 2 times the actual voltage. On the wire connection, we separate the low-voltage circuit from the high-voltage circuit and fully consider the direction of the wire routing. The installation of high-voltage components is completely separate from the installation of low-voltage control devices, which prevents high-voltage magnetic fields from interfering with the low-voltage control system and increases the safety of the equipment. We have done a lot of technical consultation work on the installation carrier of high-voltage components. We use PP plates with high pressure resistance and low cost to make boxes. High-voltage components are installed in PP plate boxes to prevent high-pressure air ionization, sharp-angle discharge, etc. When the situation occurs, we isolate the high voltage components from each other. In order to ensure the safety of the equipment, the equipment fully considers the high-voltage non-exposed and grounded safety treatment, which meets the high requirements of equipment use.

5 Conclusion

The device has been used by the user for more than half a year. The whole machine runs stably and reliably, the detection speed is fast, the judgment is accurate, and the user feedback is good. The product can reduce the labor intensity of workers, improve the quality of products and production efficiency, and has a high promotion value in the production of small dense lead-acid batteries.

Gate Valve

Gate Valve,Stainless Steel Gate Valve,Stem Gate Valve

Kangwei Die Casting Moulds Co., Ltd. , http://www.ytdiecastings.com