pin gear

例句：

1. 1. The car'sengine is controlled by a pin gear system.
   汽车的发动机由一个棘轮系统控制。
2. 2.The old clock had a pin gear thatcould be adjusted to change the time.
   旧时钟有一个可以调整的棘轮，可以改变时间。
3. 3. The engineer used a pin gearto adjust the speed of the machine.
   工程师使用棘轮来调整机器的速度。