Pink nut of green screw has a rectangular pin that moves in L-shaped slot of the brown vertical tube.
Green screw is fixed to the green bevel gear.
Rotate orange gear counterclockwise to move blue arm up and to turn it aside for loading material into the large cylinder.
Do inversely for pressing down the material.
Blue arm can move vertically only when the nut pin is in vertical portion of the L-shaped slot.
Blue arm can move horizontally only when the nut pin is in horizontal portion of the L-shaped slot.