step - less speed operation

• 无级调速

step - less speed operation的用法和样例：

例句

1. The spindles motor uses electromagnetic stepless speed regulation ,and adapts to cutting for different materials.
   主轴电机电磁无级调速，适应不同材质的裁切。
2. Stepless frequency modulated speed,low noise,low vibration driving and smooth running.
   速度无级调速，低噪音，低振动传动，运行平稳。