I think those were Simplex made cranks. They should say on the outside if you look carefully but the markings weren't really deep. I have a set but were a dual chrainring setup. I love that classic trispoke spider design. What did those come on? Something british or French?
The ones Schwinn used on older Paramounts were different. If you look at the shape of the spider it's shaped differently. Plus it had rivets instead of socket headed bolts.
They also came on the Superior(aka baby Paramount)
But as you see both only came in a skiptooth version only. I'm thinking anything besides Stronglights as they have a very noticeable marking on arms and indention's in the spider arms. They could also be Nervar's or Durax's.
Most common three spoke Stronglight 54 crankset