Stepless lifting adjusting mechanism

The utility model provides a stepless lifting adjusting mechanism. The stepless lifting adjusting mechanism is characterized in that a movable bushing and a fixed bushing are respectively provided with two wings; the fixed bushing is positioned in the fixed pipe and is fixed on the bushing fixing plate; the movable bushing is positioned in the fixed pipe; the included angle between the two wings of the movable lining is smaller than that between the two outer surfaces, facing the movable lining, of the seat insertion pipe; the seat insertion pipe is inserted into a space surrounded by the movable bushing and the fixed bushing; a controllable air spring is mounted in the fixed pipe, and the upper end of the controllable air spring is connected with the bottom end of the seat insertion pipe; a handle mounting seat on the fixed pipe is hinged with an adjusting handle through a hinged shaft; the adjusting handle is provided with a cam structure. When the adjusting handle rotates downwards to a lower station, the