一、齿轮根切定义讨论现在,人们都认为直齿圆柱标准齿轮,当压力角α_(?)=20°齿数z≤17时,在滚、插齿中要产生根切。对于根切这个名词,我们认为一般高等工业学校教科书上的定义不够确切,根切是指基圆以上,还是指基圆以下?因为基圆以下是没有渐开线的,因此,根切只能在基圆以上我们认为:切去基圆根部的渐开线称之为根切;未切去基圆根部的渐开线就不能称为根切。 First, the definition of gear root cut discussion Now, people think that standard gear straight spur cylinder, when the pressure angle α _ (?) = 20 ° number of teeth z ≤ 17, roll, gear cut to produce root cut. For the root of the term, we think the general definition of high school textbooks on the definition is not exact enough, radical refers to the base circle above, or below the base circle? Because the base circle is not the following involute, and therefore only Above the base circle we think that the involute cut to the base circle root is called the root cut; the involute line rooted at the base circle can not be called the root cut.