基本解释[机] 摆动换向齿轮词组短语短语tumbler r gear 摆动换向齿轮gear tumbler 齿轮换向器tumbler gear更多词组英英字典柯林斯英英字典 a train of gears in which the gear-selection mechanism is operated by tumblers tumbler gear剑桥字典tumbler gear柯林斯字典专业释义机械工程摆动换向齿轮