Maybe a Hancock?
It looks like a Hancock to me as well. It looks like someone has put a hydraulic orbit motor on the elevator drive. I may be wrong but I can't imagine it worked very good this way.
Looks like a Johnson product to me. Maybe... The cylinders to lift the elevator tells me it unloads over the cutting edge like the old Wagner scrapers, and those were hydraulic drive... Hmm, might be an early Hancock after all.