normallyadv.通常；正常地normally engaged gear lock ring常啮合齿轮锁环normally deenergized stick relay正常失励吸持继电器normally energized track circuit闭路式轨道 电路normally open push button switch常开按钮开关normally-closed control element[计] 常闭控制元件normally extinguished signal lamp正常熄灭的信号灯normally pressured aquifer system正常压力含水层系normally distributed observations正态分布的观测值normally closed auxiliary contact常闭辅助触点normally deenergized track circuit开路式轨道电路