what troubled me is how is possible to handle chain with this kind of winch
Well, clearly you can't! The diagram you have put up shows a purely line based manual system running around the capstan down the deck hawsepipe. This does seem a bit odd as, on the face of it, from the illustrations you have put up:
- The anchor is pretty small for the size of boat
- The fairlead at the deck edge where it goes over the side looks rather insubstantial. Usually anchor rodes go overboard at a strongpoint on a vessel either from a hull mounted hawsepipe under the bow or through a reinforced fitting on the bow as it is this which takes much of the strain on the hull.
- When bringing the anchor in presumably they would take two or three turns around the capstan to prevent slippage than then feed the line manually down the deck hawsepipe as it would not self stow under its own weight as chain would.
In fact the whole arrangement looks to be pretty lightweight and unsuitable for anchoring in any adverse conditions. It's more the sort of thing you might sling over the side on a sunny afternoon in a secluded bay while having a spot of lunch!
It would be interesting to have some comments from our professional sailors.
Colin