ͬ,同步带轮,ͬ
Ϊҳ | ղ | ϵ
ͬ | ͬ
ҳ -> ͬ|ͬ -> 同步带轮
ȨУϪбͬ޹˾ ˾ַй㽭ʡϪˮ·239