Violet lever has 3 positions: forward, neutral and backward.
Ball spring device for the lever positioning is not shown.
Green and blue gears are in permanent mesh. When left pink gear is in mesh with the blue gear, grey slider goes forward. When right pink gear is in mesh with the green gear, grey slider goes backward.
The lever neutral position is for stopping the grey slider or setting its position (by hand turning orange screw).
The mechanism is suitable for low speed.
In case of high speed stop the input before reversing.
STEP files of this video:
[ Ссылка ]
Inventor files:
[ Ссылка ]
