Yes the old timer is correct. That tool is used for installing solid tires on wheels using wire.
As you turn the crank the two spinals with slots rotate in opposite directions and the two arms in the middle hold the rubber apart.
Fast forward this video to approximately 2:30 minutes into the video to where he is setting up a machine. This machine is not exactly the same as yours but very similar in functional concept. That should give you a very good idea how your machine works.