When installed the high-pole lamp is automatically hung in a hook-shaped trough of the hanging hook after raising to the position of the automatic hanging and unloading gear ;
安装灯具时，灯具上升到自动挂钩 卸 荷 装置的位置后自动挂到吊钩的钩形槽里；
Calculation of theoretical flow and unloading groove of helical gear pump
斜 齿 齿轮泵理论排量与 卸 荷槽的计算
卸载（传动）装置，卸荷装置