Introduction of the working process of automatic battery spot welding machine

One is to adjust the effective value of the welding current to make the heat of the internal power supply change significantly; second, due to the point concentration and shrinkage at the contact point of the two weldments during the operation of the automatic spot welding machine, there occurs Concentrated heating, and the plastic joint area first seems to form uneven during spot welding. Add this unfavorable factor, different welding current waveforms, changing electrode shape and end face size, etc, it can change the shape of the current field, control the density distribution of the current, and achieve the purpose of controlling the shape and position. The resistance heat generated is increased, and the shear strength of spot weld nugget and joint is improved.

However, if the welding current is too large, it will cause the base material to overheat, and even the loss of the electrode end face will increase. When spot welding when the 18650 lithium battery is energized, the heat generated by the two electrodes is used to heat the welding area to form a welding point, which is called effective heat. For a certain welding material and a certain welding zone metal volume is fixed, it has nothing to do with the length of heating time; another part is transferred to the electrode, the cold metal around the welding zone and the air when heating, which is called heat loss, which increases with the passage of time. If welding is performed instantaneously, the heat loss will be equal to zero, and the total heat is equal to the effective heat. Therefore, when the total amount of heat is to be increased, a method of extending the welding time cannot be used.

Electrode pressure First of all, the total resistance between the electrode pressures has a significant effect, which affects the welding heat during spot welding. Secondly, the electrode pressure has a great influence on the heat dissipation performance of the welded joint. When the electrode pressure is too small, the electricity between the two electrodes is more welding heat. At this time, the heat dissipation of the welded joint is poor, which is easy to cause spatter in the early stage; when the electrode pressure is too large, the resistance between the two electrodes is small, the current density is reduced, the welding heat is insufficient, and the heat dissipation performance of the joint is improved, resulting in nucleation The size becomes smaller and the penetration rate decreases. When the electrode pressure is strictly selected, the minimum electrode pressure should be selected without spark spatter, which can ensure energy saving and welding quality.

Welding power supply, resistance spot welding equipment usually consists of three main parts: main power supply, control device and mechanical device. Among them, the main welding power supply is one of the most important parts, and the choice of controllable welding power supply is the key.