先断后合触点: break before make contactbreakbeforemakecontact
双向先断后合触点: two way break before make contacttwo-way break-before-make contact
先: 名词1.(时间或次序在前的) earlier; before; first; in advance 短语和例子有言在先 make clear beforehand; 争先恐后 strive to be the first and fear to lag behind; 你不必先付款。 you don't have to pay in advance. 你先拟个提纲再写。 m