.. Second cage

The gear. Tove can take it after the first raven is captured.

Put it into the first joint. ( Henrik must lower the first cage so that the moved cages are in same phase. )

Now, Henrik can lift both cages up.

Henrik will open the door and Tove will put the fruit bait ( You can find the fruit on top of the tower. Tove will climb it.) in.

The first raven is warning it about the trap.

Indeed. You should get rid of that tell-tale.

Lower it down while you bait the second one. ( Remove the gear and pull the lever. Now only the second cage is up. Catch the raven. )

Same idea. The fruit and another gear are on the ledge on right Tove can now access. You have to fiddle with the lever and the gears to get the third cage alone.

Henrik will raise the first cage from the lever. Add a gear into the first joint. Lower both cages. Add a gear into the second joint. Raise all three cages. Remove the second gear. Lower the first and second cage with the lever. Open the cage and insert the fruit.