Those pictures aren't worth the entire thousand words tubby, but even so it looks to me as if that is an external contracting band brake. It probably has an adjusting screw at one end of the band (which will be a single full circle, with an anchor on one end and a link to the brake pedal on the other). Find the end that is the brake pedal link, and verify that it moves in the tightening direction when the pedal is pushed down. Most likely the pedal adjustment screw will be on the anchor end, but it might be on the link end.
It looks as if the friction material was not properly attached to the inside of the band, and it has come off. That is the woven material hanging out all around - it used to be brake lining.
You could remove the band and take it to a brake reliner for repair.
