带传动的几何尺寸 1包角ca1=丌-2 6 2 ≈sIn 6 C 2a 2 c1=元 (rad)或a1=180 57.3 2a三、带传动的几何尺寸 1.包角 1 =  − 2 0 2 1 0 1 2 1 1 ( ) 180 57.3 2  − = − −  = − a d d rad a d d   或 a d d 2 sin 2 − 1    =