Method for determining process size of cold-drawn trapezoidal copper bar

The invention belongs to the field of direct-current motor commutator design, and particularly relates to a method for determining the process size of a cold-drawn trapezoidal copper bar. The method comprises the steps that S1, the large head size, the angle size and the height size of a formed trapezoidal copper bar are obtained; S2, the height size before finish machining is determined, and thesmall head size of the trapezoidal copper bar is calculated; S3, the size of a large head, the size of a small head and the height size are determined before the pressing angle; S4, the height size before squaring is determined; S5, the width size before flattening is determined; S6, the sectional area of the raw material is determined; and S7, the diameter of the raw material is determined according to the round-square transformation coefficient of the cold drawing process. The defects of original stamping machining are eliminated, the part size is stable, the surface quality consistency is good, the purposes of impr