Three point hydraulic aircraft jack - has three levelling pistons operated from one central position

摘要

A three legged hydraulic jack as used for aircraft maintenance has a wheel and a vertical spindle with support plate attached to each leg. Each wheel assembly is carried by the piston of a vertical cylinder. When the load spindle of the jack is set to an accurate vertical orientation, the unloaded jack is moved by pressurizing the wheel pistons from a hydraulic hand operated pump. Control valves and a circular spirit level are located next to the hand pump so that the operator is able to set up the jack from one central point. When the jack is level, the support plates are screwed down hence allowing the wheels to be raised from the ground.