二次电极间接法(下称“二间法”),与一般的电火花加工方法相反,是用特有凹模精度的二次电极——再以电火花加工方法——对冲裁用凸模(冲头)进行加工的一种新方法。“二间法”加工原理,如图1A所示。首先,用磨削等加工方法制成与凸模形状一样的一次电极。如果电极特定部分的尺寸为D,则凹凸模之间的间隙,从图1B可以得到: The secondary electrode indirect method (hereinafter referred to as “two methods”), in contrast with the general EDM method, is the use of unique secondary precision die accuracy - then EDM - punch punching Punch) for processing a new method. The “two methods” processing principle, shown in Figure 1A. First, a primary electrode having the same shape as the punch is formed by a grinding method or the like. If the size of the specific part of the electrode is D, the gap between the concave and convex molds can be obtained from FIG. 1B: