一、点焊热量的控制方式点焊在汽车生产中应用普遍,尤其是在车身、车箱、车架的生产中占有重要的地位。点焊的质量主要由点焊时输入的热量决定。根据焦耳—楞茨定理,热量与电流的平方成正比。焊接电流的控制方式有二种:其一是通过变换焊接变压器的一次线圈的抽头,改变焊接变压器的二次电压来改变焊接电流。这种方式只是在大幅度调整时采用,且不能在焊接过程中进 First, the control method of spot welding Spot welding is widely used in automobile production, especially in the body, trunk, frame production occupies an important position. The quality of spot welding is mainly determined by the heat input during spot welding. According to Joule - Lorentz’s theorem, the heat is proportional to the square of the current. There are two ways to control the welding current: One is to change the welding current by changing the tap of the primary winding of the welding transformer and changing the secondary voltage of the welding transformer. This method is only used when adjusting greatly, and can not enter the welding process