It comprises an in-put shaft hinged to its yoke through one axis, and an out-put shaft also hinged to its yoke through another axis, and these two yokes (13) were combined together by only one axis position, perpendicular to that two yoke axes like a cross, so that this combined axis will bend just like the angle bisector of that two shafts to maintain its constant velocity by a few methods, firstly, by using a section of gear teeth mesh at both ends of the shafts'teeth were so polished so that it can turn longitudinally as usual gear, and also sideways, to provide a larger solid angle of turning from ordinary 45 degrees into 60 or even more.
它包括输入轴，其通过一根轴铰链连接于叉形支架，和输出轴，其通过另一根轴也铰链连接于其叉形支架。并且这两个叉形支架(13)只需用一根相对垂直铰链轴相连而组合在一起，使得这种组合的轴总能形成这两个轴的角平分线，以通过少数几种方法保持其恒速，首先，通过用啮合在轴的两端的一段齿轮齿抛光为以能够像普通齿轮一样纵向转动，并且还能够侧向转动，以提供较大的转向立体角，从通常的45度变成60度或更大。